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1 | /* | |
2 | * A driver for the ARM PL022 PrimeCell SSP/SPI bus master. | |
3 | * | |
4 | * Copyright (C) 2008-2009 ST-Ericsson AB | |
5 | * Copyright (C) 2006 STMicroelectronics Pvt. Ltd. | |
6 | * | |
7 | * Author: Linus Walleij <linus.walleij@stericsson.com> | |
8 | * | |
9 | * Initial version inspired by: | |
10 | * linux-2.6.17-rc3-mm1/drivers/spi/pxa2xx_spi.c | |
11 | * Initial adoption to PL022 by: | |
12 | * Sachin Verma <sachin.verma@st.com> | |
13 | * | |
14 | * This program is free software; you can redistribute it and/or modify | |
15 | * it under the terms of the GNU General Public License as published by | |
16 | * the Free Software Foundation; either version 2 of the License, or | |
17 | * (at your option) any later version. | |
18 | * | |
19 | * This program is distributed in the hope that it will be useful, | |
20 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
21 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
22 | * GNU General Public License for more details. | |
23 | */ | |
24 | ||
25 | #include <linux/init.h> | |
26 | #include <linux/module.h> | |
27 | #include <linux/device.h> | |
28 | #include <linux/ioport.h> | |
29 | #include <linux/errno.h> | |
30 | #include <linux/interrupt.h> | |
31 | #include <linux/spi/spi.h> | |
32 | #include <linux/workqueue.h> | |
33 | #include <linux/delay.h> | |
34 | #include <linux/clk.h> | |
35 | #include <linux/err.h> | |
36 | #include <linux/amba/bus.h> | |
37 | #include <linux/amba/pl022.h> | |
38 | #include <linux/io.h> | |
39 | #include <linux/slab.h> | |
40 | #include <linux/dmaengine.h> | |
41 | #include <linux/dma-mapping.h> | |
42 | #include <linux/scatterlist.h> | |
43 | #include <linux/pm_runtime.h> | |
44 | ||
45 | /* | |
46 | * This macro is used to define some register default values. | |
47 | * reg is masked with mask, the OR:ed with an (again masked) | |
48 | * val shifted sb steps to the left. | |
49 | */ | |
50 | #define SSP_WRITE_BITS(reg, val, mask, sb) \ | |
51 | ((reg) = (((reg) & ~(mask)) | (((val)<<(sb)) & (mask)))) | |
52 | ||
53 | /* | |
54 | * This macro is also used to define some default values. | |
55 | * It will just shift val by sb steps to the left and mask | |
56 | * the result with mask. | |
57 | */ | |
58 | #define GEN_MASK_BITS(val, mask, sb) \ | |
59 | (((val)<<(sb)) & (mask)) | |
60 | ||
61 | #define DRIVE_TX 0 | |
62 | #define DO_NOT_DRIVE_TX 1 | |
63 | ||
64 | #define DO_NOT_QUEUE_DMA 0 | |
65 | #define QUEUE_DMA 1 | |
66 | ||
67 | #define RX_TRANSFER 1 | |
68 | #define TX_TRANSFER 2 | |
69 | ||
70 | /* | |
71 | * Macros to access SSP Registers with their offsets | |
72 | */ | |
73 | #define SSP_CR0(r) (r + 0x000) | |
74 | #define SSP_CR1(r) (r + 0x004) | |
75 | #define SSP_DR(r) (r + 0x008) | |
76 | #define SSP_SR(r) (r + 0x00C) | |
77 | #define SSP_CPSR(r) (r + 0x010) | |
78 | #define SSP_IMSC(r) (r + 0x014) | |
79 | #define SSP_RIS(r) (r + 0x018) | |
80 | #define SSP_MIS(r) (r + 0x01C) | |
81 | #define SSP_ICR(r) (r + 0x020) | |
82 | #define SSP_DMACR(r) (r + 0x024) | |
83 | #define SSP_ITCR(r) (r + 0x080) | |
84 | #define SSP_ITIP(r) (r + 0x084) | |
85 | #define SSP_ITOP(r) (r + 0x088) | |
86 | #define SSP_TDR(r) (r + 0x08C) | |
87 | ||
88 | #define SSP_PID0(r) (r + 0xFE0) | |
89 | #define SSP_PID1(r) (r + 0xFE4) | |
90 | #define SSP_PID2(r) (r + 0xFE8) | |
91 | #define SSP_PID3(r) (r + 0xFEC) | |
92 | ||
93 | #define SSP_CID0(r) (r + 0xFF0) | |
94 | #define SSP_CID1(r) (r + 0xFF4) | |
95 | #define SSP_CID2(r) (r + 0xFF8) | |
96 | #define SSP_CID3(r) (r + 0xFFC) | |
97 | ||
98 | /* | |
99 | * SSP Control Register 0 - SSP_CR0 | |
100 | */ | |
101 | #define SSP_CR0_MASK_DSS (0x0FUL << 0) | |
102 | #define SSP_CR0_MASK_FRF (0x3UL << 4) | |
103 | #define SSP_CR0_MASK_SPO (0x1UL << 6) | |
104 | #define SSP_CR0_MASK_SPH (0x1UL << 7) | |
105 | #define SSP_CR0_MASK_SCR (0xFFUL << 8) | |
106 | ||
107 | /* | |
108 | * The ST version of this block moves som bits | |
109 | * in SSP_CR0 and extends it to 32 bits | |
110 | */ | |
111 | #define SSP_CR0_MASK_DSS_ST (0x1FUL << 0) | |
112 | #define SSP_CR0_MASK_HALFDUP_ST (0x1UL << 5) | |
113 | #define SSP_CR0_MASK_CSS_ST (0x1FUL << 16) | |
114 | #define SSP_CR0_MASK_FRF_ST (0x3UL << 21) | |
115 | ||
116 | /* | |
117 | * SSP Control Register 0 - SSP_CR1 | |
118 | */ | |
119 | #define SSP_CR1_MASK_LBM (0x1UL << 0) | |
120 | #define SSP_CR1_MASK_SSE (0x1UL << 1) | |
121 | #define SSP_CR1_MASK_MS (0x1UL << 2) | |
122 | #define SSP_CR1_MASK_SOD (0x1UL << 3) | |
123 | ||
124 | /* | |
125 | * The ST version of this block adds some bits | |
126 | * in SSP_CR1 | |
127 | */ | |
128 | #define SSP_CR1_MASK_RENDN_ST (0x1UL << 4) | |
129 | #define SSP_CR1_MASK_TENDN_ST (0x1UL << 5) | |
130 | #define SSP_CR1_MASK_MWAIT_ST (0x1UL << 6) | |
131 | #define SSP_CR1_MASK_RXIFLSEL_ST (0x7UL << 7) | |
132 | #define SSP_CR1_MASK_TXIFLSEL_ST (0x7UL << 10) | |
133 | /* This one is only in the PL023 variant */ | |
134 | #define SSP_CR1_MASK_FBCLKDEL_ST (0x7UL << 13) | |
135 | ||
136 | /* | |
137 | * SSP Status Register - SSP_SR | |
138 | */ | |
139 | #define SSP_SR_MASK_TFE (0x1UL << 0) /* Transmit FIFO empty */ | |
140 | #define SSP_SR_MASK_TNF (0x1UL << 1) /* Transmit FIFO not full */ | |
141 | #define SSP_SR_MASK_RNE (0x1UL << 2) /* Receive FIFO not empty */ | |
142 | #define SSP_SR_MASK_RFF (0x1UL << 3) /* Receive FIFO full */ | |
143 | #define SSP_SR_MASK_BSY (0x1UL << 4) /* Busy Flag */ | |
144 | ||
145 | /* | |
146 | * SSP Clock Prescale Register - SSP_CPSR | |
147 | */ | |
148 | #define SSP_CPSR_MASK_CPSDVSR (0xFFUL << 0) | |
149 | ||
150 | /* | |
151 | * SSP Interrupt Mask Set/Clear Register - SSP_IMSC | |
152 | */ | |
153 | #define SSP_IMSC_MASK_RORIM (0x1UL << 0) /* Receive Overrun Interrupt mask */ | |
154 | #define SSP_IMSC_MASK_RTIM (0x1UL << 1) /* Receive timeout Interrupt mask */ | |
155 | #define SSP_IMSC_MASK_RXIM (0x1UL << 2) /* Receive FIFO Interrupt mask */ | |
156 | #define SSP_IMSC_MASK_TXIM (0x1UL << 3) /* Transmit FIFO Interrupt mask */ | |
157 | ||
158 | /* | |
159 | * SSP Raw Interrupt Status Register - SSP_RIS | |
160 | */ | |
161 | /* Receive Overrun Raw Interrupt status */ | |
162 | #define SSP_RIS_MASK_RORRIS (0x1UL << 0) | |
163 | /* Receive Timeout Raw Interrupt status */ | |
164 | #define SSP_RIS_MASK_RTRIS (0x1UL << 1) | |
165 | /* Receive FIFO Raw Interrupt status */ | |
166 | #define SSP_RIS_MASK_RXRIS (0x1UL << 2) | |
167 | /* Transmit FIFO Raw Interrupt status */ | |
168 | #define SSP_RIS_MASK_TXRIS (0x1UL << 3) | |
169 | ||
170 | /* | |
171 | * SSP Masked Interrupt Status Register - SSP_MIS | |
172 | */ | |
173 | /* Receive Overrun Masked Interrupt status */ | |
174 | #define SSP_MIS_MASK_RORMIS (0x1UL << 0) | |
175 | /* Receive Timeout Masked Interrupt status */ | |
176 | #define SSP_MIS_MASK_RTMIS (0x1UL << 1) | |
177 | /* Receive FIFO Masked Interrupt status */ | |
178 | #define SSP_MIS_MASK_RXMIS (0x1UL << 2) | |
179 | /* Transmit FIFO Masked Interrupt status */ | |
180 | #define SSP_MIS_MASK_TXMIS (0x1UL << 3) | |
181 | ||
182 | /* | |
183 | * SSP Interrupt Clear Register - SSP_ICR | |
184 | */ | |
185 | /* Receive Overrun Raw Clear Interrupt bit */ | |
186 | #define SSP_ICR_MASK_RORIC (0x1UL << 0) | |
187 | /* Receive Timeout Clear Interrupt bit */ | |
188 | #define SSP_ICR_MASK_RTIC (0x1UL << 1) | |
189 | ||
190 | /* | |
191 | * SSP DMA Control Register - SSP_DMACR | |
192 | */ | |
193 | /* Receive DMA Enable bit */ | |
194 | #define SSP_DMACR_MASK_RXDMAE (0x1UL << 0) | |
195 | /* Transmit DMA Enable bit */ | |
196 | #define SSP_DMACR_MASK_TXDMAE (0x1UL << 1) | |
197 | ||
198 | /* | |
199 | * SSP Integration Test control Register - SSP_ITCR | |
200 | */ | |
201 | #define SSP_ITCR_MASK_ITEN (0x1UL << 0) | |
202 | #define SSP_ITCR_MASK_TESTFIFO (0x1UL << 1) | |
203 | ||
204 | /* | |
205 | * SSP Integration Test Input Register - SSP_ITIP | |
206 | */ | |
207 | #define ITIP_MASK_SSPRXD (0x1UL << 0) | |
208 | #define ITIP_MASK_SSPFSSIN (0x1UL << 1) | |
209 | #define ITIP_MASK_SSPCLKIN (0x1UL << 2) | |
210 | #define ITIP_MASK_RXDMAC (0x1UL << 3) | |
211 | #define ITIP_MASK_TXDMAC (0x1UL << 4) | |
212 | #define ITIP_MASK_SSPTXDIN (0x1UL << 5) | |
213 | ||
214 | /* | |
215 | * SSP Integration Test output Register - SSP_ITOP | |
216 | */ | |
217 | #define ITOP_MASK_SSPTXD (0x1UL << 0) | |
218 | #define ITOP_MASK_SSPFSSOUT (0x1UL << 1) | |
219 | #define ITOP_MASK_SSPCLKOUT (0x1UL << 2) | |
220 | #define ITOP_MASK_SSPOEn (0x1UL << 3) | |
221 | #define ITOP_MASK_SSPCTLOEn (0x1UL << 4) | |
222 | #define ITOP_MASK_RORINTR (0x1UL << 5) | |
223 | #define ITOP_MASK_RTINTR (0x1UL << 6) | |
224 | #define ITOP_MASK_RXINTR (0x1UL << 7) | |
225 | #define ITOP_MASK_TXINTR (0x1UL << 8) | |
226 | #define ITOP_MASK_INTR (0x1UL << 9) | |
227 | #define ITOP_MASK_RXDMABREQ (0x1UL << 10) | |
228 | #define ITOP_MASK_RXDMASREQ (0x1UL << 11) | |
229 | #define ITOP_MASK_TXDMABREQ (0x1UL << 12) | |
230 | #define ITOP_MASK_TXDMASREQ (0x1UL << 13) | |
231 | ||
232 | /* | |
233 | * SSP Test Data Register - SSP_TDR | |
234 | */ | |
235 | #define TDR_MASK_TESTDATA (0xFFFFFFFF) | |
236 | ||
237 | /* | |
238 | * Message State | |
239 | * we use the spi_message.state (void *) pointer to | |
240 | * hold a single state value, that's why all this | |
241 | * (void *) casting is done here. | |
242 | */ | |
243 | #define STATE_START ((void *) 0) | |
244 | #define STATE_RUNNING ((void *) 1) | |
245 | #define STATE_DONE ((void *) 2) | |
246 | #define STATE_ERROR ((void *) -1) | |
247 | ||
248 | /* | |
249 | * SSP State - Whether Enabled or Disabled | |
250 | */ | |
251 | #define SSP_DISABLED (0) | |
252 | #define SSP_ENABLED (1) | |
253 | ||
254 | /* | |
255 | * SSP DMA State - Whether DMA Enabled or Disabled | |
256 | */ | |
257 | #define SSP_DMA_DISABLED (0) | |
258 | #define SSP_DMA_ENABLED (1) | |
259 | ||
260 | /* | |
261 | * SSP Clock Defaults | |
262 | */ | |
263 | #define SSP_DEFAULT_CLKRATE 0x2 | |
264 | #define SSP_DEFAULT_PRESCALE 0x40 | |
265 | ||
266 | /* | |
267 | * SSP Clock Parameter ranges | |
268 | */ | |
269 | #define CPSDVR_MIN 0x02 | |
270 | #define CPSDVR_MAX 0xFE | |
271 | #define SCR_MIN 0x00 | |
272 | #define SCR_MAX 0xFF | |
273 | ||
274 | /* | |
275 | * SSP Interrupt related Macros | |
276 | */ | |
277 | #define DEFAULT_SSP_REG_IMSC 0x0UL | |
278 | #define DISABLE_ALL_INTERRUPTS DEFAULT_SSP_REG_IMSC | |
279 | #define ENABLE_ALL_INTERRUPTS (~DEFAULT_SSP_REG_IMSC) | |
280 | ||
281 | #define CLEAR_ALL_INTERRUPTS 0x3 | |
282 | ||
283 | #define SPI_POLLING_TIMEOUT 1000 | |
284 | ||
285 | /* | |
286 | * The type of reading going on on this chip | |
287 | */ | |
288 | enum ssp_reading { | |
289 | READING_NULL, | |
290 | READING_U8, | |
291 | READING_U16, | |
292 | READING_U32 | |
293 | }; | |
294 | ||
295 | /** | |
296 | * The type of writing going on on this chip | |
297 | */ | |
298 | enum ssp_writing { | |
299 | WRITING_NULL, | |
300 | WRITING_U8, | |
301 | WRITING_U16, | |
302 | WRITING_U32 | |
303 | }; | |
304 | ||
305 | /** | |
306 | * struct vendor_data - vendor-specific config parameters | |
307 | * for PL022 derivates | |
308 | * @fifodepth: depth of FIFOs (both) | |
309 | * @max_bpw: maximum number of bits per word | |
310 | * @unidir: supports unidirection transfers | |
311 | * @extended_cr: 32 bit wide control register 0 with extra | |
312 | * features and extra features in CR1 as found in the ST variants | |
313 | * @pl023: supports a subset of the ST extensions called "PL023" | |
314 | */ | |
315 | struct vendor_data { | |
316 | int fifodepth; | |
317 | int max_bpw; | |
318 | bool unidir; | |
319 | bool extended_cr; | |
320 | bool pl023; | |
321 | bool loopback; | |
322 | }; | |
323 | ||
324 | /** | |
325 | * struct pl022 - This is the private SSP driver data structure | |
326 | * @adev: AMBA device model hookup | |
327 | * @vendor: vendor data for the IP block | |
328 | * @phybase: the physical memory where the SSP device resides | |
329 | * @virtbase: the virtual memory where the SSP is mapped | |
330 | * @clk: outgoing clock "SPICLK" for the SPI bus | |
331 | * @master: SPI framework hookup | |
332 | * @master_info: controller-specific data from machine setup | |
333 | * @workqueue: a workqueue on which any spi_message request is queued | |
334 | * @pump_messages: work struct for scheduling work to the workqueue | |
335 | * @queue_lock: spinlock to syncronise access to message queue | |
336 | * @queue: message queue | |
337 | * @busy: workqueue is busy | |
338 | * @running: workqueue is running | |
339 | * @pump_transfers: Tasklet used in Interrupt Transfer mode | |
340 | * @cur_msg: Pointer to current spi_message being processed | |
341 | * @cur_transfer: Pointer to current spi_transfer | |
342 | * @cur_chip: pointer to current clients chip(assigned from controller_state) | |
343 | * @tx: current position in TX buffer to be read | |
344 | * @tx_end: end position in TX buffer to be read | |
345 | * @rx: current position in RX buffer to be written | |
346 | * @rx_end: end position in RX buffer to be written | |
347 | * @read: the type of read currently going on | |
348 | * @write: the type of write currently going on | |
349 | * @exp_fifo_level: expected FIFO level | |
350 | * @dma_rx_channel: optional channel for RX DMA | |
351 | * @dma_tx_channel: optional channel for TX DMA | |
352 | * @sgt_rx: scattertable for the RX transfer | |
353 | * @sgt_tx: scattertable for the TX transfer | |
354 | * @dummypage: a dummy page used for driving data on the bus with DMA | |
355 | */ | |
356 | struct pl022 { | |
357 | struct amba_device *adev; | |
358 | struct vendor_data *vendor; | |
359 | resource_size_t phybase; | |
360 | void __iomem *virtbase; | |
361 | struct clk *clk; | |
362 | struct spi_master *master; | |
363 | struct pl022_ssp_controller *master_info; | |
364 | /* Driver message queue */ | |
365 | struct workqueue_struct *workqueue; | |
366 | struct work_struct pump_messages; | |
367 | spinlock_t queue_lock; | |
368 | struct list_head queue; | |
369 | bool busy; | |
370 | bool running; | |
371 | /* Message transfer pump */ | |
372 | struct tasklet_struct pump_transfers; | |
373 | struct spi_message *cur_msg; | |
374 | struct spi_transfer *cur_transfer; | |
375 | struct chip_data *cur_chip; | |
376 | void *tx; | |
377 | void *tx_end; | |
378 | void *rx; | |
379 | void *rx_end; | |
380 | enum ssp_reading read; | |
381 | enum ssp_writing write; | |
382 | u32 exp_fifo_level; | |
383 | enum ssp_rx_level_trig rx_lev_trig; | |
384 | enum ssp_tx_level_trig tx_lev_trig; | |
385 | /* DMA settings */ | |
386 | #ifdef CONFIG_DMA_ENGINE | |
387 | struct dma_chan *dma_rx_channel; | |
388 | struct dma_chan *dma_tx_channel; | |
389 | struct sg_table sgt_rx; | |
390 | struct sg_table sgt_tx; | |
391 | char *dummypage; | |
392 | #endif | |
393 | }; | |
394 | ||
395 | /** | |
396 | * struct chip_data - To maintain runtime state of SSP for each client chip | |
397 | * @cr0: Value of control register CR0 of SSP - on later ST variants this | |
398 | * register is 32 bits wide rather than just 16 | |
399 | * @cr1: Value of control register CR1 of SSP | |
400 | * @dmacr: Value of DMA control Register of SSP | |
401 | * @cpsr: Value of Clock prescale register | |
402 | * @n_bytes: how many bytes(power of 2) reqd for a given data width of client | |
403 | * @enable_dma: Whether to enable DMA or not | |
404 | * @read: function ptr to be used to read when doing xfer for this chip | |
405 | * @write: function ptr to be used to write when doing xfer for this chip | |
406 | * @cs_control: chip select callback provided by chip | |
407 | * @xfer_type: polling/interrupt/DMA | |
408 | * | |
409 | * Runtime state of the SSP controller, maintained per chip, | |
410 | * This would be set according to the current message that would be served | |
411 | */ | |
412 | struct chip_data { | |
413 | u32 cr0; | |
414 | u16 cr1; | |
415 | u16 dmacr; | |
416 | u16 cpsr; | |
417 | u8 n_bytes; | |
418 | bool enable_dma; | |
419 | enum ssp_reading read; | |
420 | enum ssp_writing write; | |
421 | void (*cs_control) (u32 command); | |
422 | int xfer_type; | |
423 | }; | |
424 | ||
425 | /** | |
426 | * null_cs_control - Dummy chip select function | |
427 | * @command: select/delect the chip | |
428 | * | |
429 | * If no chip select function is provided by client this is used as dummy | |
430 | * chip select | |
431 | */ | |
432 | static void null_cs_control(u32 command) | |
433 | { | |
434 | pr_debug("pl022: dummy chip select control, CS=0x%x\n", command); | |
435 | } | |
436 | ||
437 | /** | |
438 | * giveback - current spi_message is over, schedule next message and call | |
439 | * callback of this message. Assumes that caller already | |
440 | * set message->status; dma and pio irqs are blocked | |
441 | * @pl022: SSP driver private data structure | |
442 | */ | |
443 | static void giveback(struct pl022 *pl022) | |
444 | { | |
445 | struct spi_transfer *last_transfer; | |
446 | unsigned long flags; | |
447 | struct spi_message *msg; | |
448 | void (*curr_cs_control) (u32 command); | |
449 | ||
450 | /* | |
451 | * This local reference to the chip select function | |
452 | * is needed because we set curr_chip to NULL | |
453 | * as a step toward termininating the message. | |
454 | */ | |
455 | curr_cs_control = pl022->cur_chip->cs_control; | |
456 | spin_lock_irqsave(&pl022->queue_lock, flags); | |
457 | msg = pl022->cur_msg; | |
458 | pl022->cur_msg = NULL; | |
459 | pl022->cur_transfer = NULL; | |
460 | pl022->cur_chip = NULL; | |
461 | queue_work(pl022->workqueue, &pl022->pump_messages); | |
462 | spin_unlock_irqrestore(&pl022->queue_lock, flags); | |
463 | ||
464 | last_transfer = list_entry(msg->transfers.prev, | |
465 | struct spi_transfer, | |
466 | transfer_list); | |
467 | ||
468 | /* Delay if requested before any change in chip select */ | |
469 | if (last_transfer->delay_usecs) | |
470 | /* | |
471 | * FIXME: This runs in interrupt context. | |
472 | * Is this really smart? | |
473 | */ | |
474 | udelay(last_transfer->delay_usecs); | |
475 | ||
476 | /* | |
477 | * Drop chip select UNLESS cs_change is true or we are returning | |
478 | * a message with an error, or next message is for another chip | |
479 | */ | |
480 | if (!last_transfer->cs_change) | |
481 | curr_cs_control(SSP_CHIP_DESELECT); | |
482 | else { | |
483 | struct spi_message *next_msg; | |
484 | ||
485 | /* Holding of cs was hinted, but we need to make sure | |
486 | * the next message is for the same chip. Don't waste | |
487 | * time with the following tests unless this was hinted. | |
488 | * | |
489 | * We cannot postpone this until pump_messages, because | |
490 | * after calling msg->complete (below) the driver that | |
491 | * sent the current message could be unloaded, which | |
492 | * could invalidate the cs_control() callback... | |
493 | */ | |
494 | ||
495 | /* get a pointer to the next message, if any */ | |
496 | spin_lock_irqsave(&pl022->queue_lock, flags); | |
497 | if (list_empty(&pl022->queue)) | |
498 | next_msg = NULL; | |
499 | else | |
500 | next_msg = list_entry(pl022->queue.next, | |
501 | struct spi_message, queue); | |
502 | spin_unlock_irqrestore(&pl022->queue_lock, flags); | |
503 | ||
504 | /* see if the next and current messages point | |
505 | * to the same chip | |
506 | */ | |
507 | if (next_msg && next_msg->spi != msg->spi) | |
508 | next_msg = NULL; | |
509 | if (!next_msg || msg->state == STATE_ERROR) | |
510 | curr_cs_control(SSP_CHIP_DESELECT); | |
511 | } | |
512 | msg->state = NULL; | |
513 | if (msg->complete) | |
514 | msg->complete(msg->context); | |
515 | /* This message is completed, so let's turn off the clocks & power */ | |
516 | pm_runtime_put(&pl022->adev->dev); | |
517 | } | |
518 | ||
519 | /** | |
520 | * flush - flush the FIFO to reach a clean state | |
521 | * @pl022: SSP driver private data structure | |
522 | */ | |
523 | static int flush(struct pl022 *pl022) | |
524 | { | |
525 | unsigned long limit = loops_per_jiffy << 1; | |
526 | ||
527 | dev_dbg(&pl022->adev->dev, "flush\n"); | |
528 | do { | |
529 | while (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE) | |
530 | readw(SSP_DR(pl022->virtbase)); | |
531 | } while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_BSY) && limit--); | |
532 | ||
533 | pl022->exp_fifo_level = 0; | |
534 | ||
535 | return limit; | |
536 | } | |
537 | ||
538 | /** | |
539 | * restore_state - Load configuration of current chip | |
540 | * @pl022: SSP driver private data structure | |
541 | */ | |
542 | static void restore_state(struct pl022 *pl022) | |
543 | { | |
544 | struct chip_data *chip = pl022->cur_chip; | |
545 | ||
546 | if (pl022->vendor->extended_cr) | |
547 | writel(chip->cr0, SSP_CR0(pl022->virtbase)); | |
548 | else | |
549 | writew(chip->cr0, SSP_CR0(pl022->virtbase)); | |
550 | writew(chip->cr1, SSP_CR1(pl022->virtbase)); | |
551 | writew(chip->dmacr, SSP_DMACR(pl022->virtbase)); | |
552 | writew(chip->cpsr, SSP_CPSR(pl022->virtbase)); | |
553 | writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase)); | |
554 | writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase)); | |
555 | } | |
556 | ||
557 | /* | |
558 | * Default SSP Register Values | |
559 | */ | |
560 | #define DEFAULT_SSP_REG_CR0 ( \ | |
561 | GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS, 0) | \ | |
562 | GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF, 4) | \ | |
563 | GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \ | |
564 | GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \ | |
565 | GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \ | |
566 | ) | |
567 | ||
568 | /* ST versions have slightly different bit layout */ | |
569 | #define DEFAULT_SSP_REG_CR0_ST ( \ | |
570 | GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0) | \ | |
571 | GEN_MASK_BITS(SSP_MICROWIRE_CHANNEL_FULL_DUPLEX, SSP_CR0_MASK_HALFDUP_ST, 5) | \ | |
572 | GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \ | |
573 | GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \ | |
574 | GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) | \ | |
575 | GEN_MASK_BITS(SSP_BITS_8, SSP_CR0_MASK_CSS_ST, 16) | \ | |
576 | GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF_ST, 21) \ | |
577 | ) | |
578 | ||
579 | /* The PL023 version is slightly different again */ | |
580 | #define DEFAULT_SSP_REG_CR0_ST_PL023 ( \ | |
581 | GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0) | \ | |
582 | GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \ | |
583 | GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \ | |
584 | GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \ | |
585 | ) | |
586 | ||
587 | #define DEFAULT_SSP_REG_CR1 ( \ | |
588 | GEN_MASK_BITS(LOOPBACK_DISABLED, SSP_CR1_MASK_LBM, 0) | \ | |
589 | GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \ | |
590 | GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \ | |
591 | GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) \ | |
592 | ) | |
593 | ||
594 | /* ST versions extend this register to use all 16 bits */ | |
595 | #define DEFAULT_SSP_REG_CR1_ST ( \ | |
596 | DEFAULT_SSP_REG_CR1 | \ | |
597 | GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \ | |
598 | GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \ | |
599 | GEN_MASK_BITS(SSP_MWIRE_WAIT_ZERO, SSP_CR1_MASK_MWAIT_ST, 6) |\ | |
600 | GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \ | |
601 | GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) \ | |
602 | ) | |
603 | ||
604 | /* | |
605 | * The PL023 variant has further differences: no loopback mode, no microwire | |
606 | * support, and a new clock feedback delay setting. | |
607 | */ | |
608 | #define DEFAULT_SSP_REG_CR1_ST_PL023 ( \ | |
609 | GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \ | |
610 | GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \ | |
611 | GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) | \ | |
612 | GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \ | |
613 | GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \ | |
614 | GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \ | |
615 | GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) | \ | |
616 | GEN_MASK_BITS(SSP_FEEDBACK_CLK_DELAY_NONE, SSP_CR1_MASK_FBCLKDEL_ST, 13) \ | |
617 | ) | |
618 | ||
619 | #define DEFAULT_SSP_REG_CPSR ( \ | |
620 | GEN_MASK_BITS(SSP_DEFAULT_PRESCALE, SSP_CPSR_MASK_CPSDVSR, 0) \ | |
621 | ) | |
622 | ||
623 | #define DEFAULT_SSP_REG_DMACR (\ | |
624 | GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_RXDMAE, 0) | \ | |
625 | GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_TXDMAE, 1) \ | |
626 | ) | |
627 | ||
628 | /** | |
629 | * load_ssp_default_config - Load default configuration for SSP | |
630 | * @pl022: SSP driver private data structure | |
631 | */ | |
632 | static void load_ssp_default_config(struct pl022 *pl022) | |
633 | { | |
634 | if (pl022->vendor->pl023) { | |
635 | writel(DEFAULT_SSP_REG_CR0_ST_PL023, SSP_CR0(pl022->virtbase)); | |
636 | writew(DEFAULT_SSP_REG_CR1_ST_PL023, SSP_CR1(pl022->virtbase)); | |
637 | } else if (pl022->vendor->extended_cr) { | |
638 | writel(DEFAULT_SSP_REG_CR0_ST, SSP_CR0(pl022->virtbase)); | |
639 | writew(DEFAULT_SSP_REG_CR1_ST, SSP_CR1(pl022->virtbase)); | |
640 | } else { | |
641 | writew(DEFAULT_SSP_REG_CR0, SSP_CR0(pl022->virtbase)); | |
642 | writew(DEFAULT_SSP_REG_CR1, SSP_CR1(pl022->virtbase)); | |
643 | } | |
644 | writew(DEFAULT_SSP_REG_DMACR, SSP_DMACR(pl022->virtbase)); | |
645 | writew(DEFAULT_SSP_REG_CPSR, SSP_CPSR(pl022->virtbase)); | |
646 | writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase)); | |
647 | writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase)); | |
648 | } | |
649 | ||
650 | /** | |
651 | * This will write to TX and read from RX according to the parameters | |
652 | * set in pl022. | |
653 | */ | |
654 | static void readwriter(struct pl022 *pl022) | |
655 | { | |
656 | ||
657 | /* | |
658 | * The FIFO depth is different between primecell variants. | |
659 | * I believe filling in too much in the FIFO might cause | |
660 | * errons in 8bit wide transfers on ARM variants (just 8 words | |
661 | * FIFO, means only 8x8 = 64 bits in FIFO) at least. | |
662 | * | |
663 | * To prevent this issue, the TX FIFO is only filled to the | |
664 | * unused RX FIFO fill length, regardless of what the TX | |
665 | * FIFO status flag indicates. | |
666 | */ | |
667 | dev_dbg(&pl022->adev->dev, | |
668 | "%s, rx: %p, rxend: %p, tx: %p, txend: %p\n", | |
669 | __func__, pl022->rx, pl022->rx_end, pl022->tx, pl022->tx_end); | |
670 | ||
671 | /* Read as much as you can */ | |
672 | while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE) | |
673 | && (pl022->rx < pl022->rx_end)) { | |
674 | switch (pl022->read) { | |
675 | case READING_NULL: | |
676 | readw(SSP_DR(pl022->virtbase)); | |
677 | break; | |
678 | case READING_U8: | |
679 | *(u8 *) (pl022->rx) = | |
680 | readw(SSP_DR(pl022->virtbase)) & 0xFFU; | |
681 | break; | |
682 | case READING_U16: | |
683 | *(u16 *) (pl022->rx) = | |
684 | (u16) readw(SSP_DR(pl022->virtbase)); | |
685 | break; | |
686 | case READING_U32: | |
687 | *(u32 *) (pl022->rx) = | |
688 | readl(SSP_DR(pl022->virtbase)); | |
689 | break; | |
690 | } | |
691 | pl022->rx += (pl022->cur_chip->n_bytes); | |
692 | pl022->exp_fifo_level--; | |
693 | } | |
694 | /* | |
695 | * Write as much as possible up to the RX FIFO size | |
696 | */ | |
697 | while ((pl022->exp_fifo_level < pl022->vendor->fifodepth) | |
698 | && (pl022->tx < pl022->tx_end)) { | |
699 | switch (pl022->write) { | |
700 | case WRITING_NULL: | |
701 | writew(0x0, SSP_DR(pl022->virtbase)); | |
702 | break; | |
703 | case WRITING_U8: | |
704 | writew(*(u8 *) (pl022->tx), SSP_DR(pl022->virtbase)); | |
705 | break; | |
706 | case WRITING_U16: | |
707 | writew((*(u16 *) (pl022->tx)), SSP_DR(pl022->virtbase)); | |
708 | break; | |
709 | case WRITING_U32: | |
710 | writel(*(u32 *) (pl022->tx), SSP_DR(pl022->virtbase)); | |
711 | break; | |
712 | } | |
713 | pl022->tx += (pl022->cur_chip->n_bytes); | |
714 | pl022->exp_fifo_level++; | |
715 | /* | |
716 | * This inner reader takes care of things appearing in the RX | |
717 | * FIFO as we're transmitting. This will happen a lot since the | |
718 | * clock starts running when you put things into the TX FIFO, | |
719 | * and then things are continuously clocked into the RX FIFO. | |
720 | */ | |
721 | while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE) | |
722 | && (pl022->rx < pl022->rx_end)) { | |
723 | switch (pl022->read) { | |
724 | case READING_NULL: | |
725 | readw(SSP_DR(pl022->virtbase)); | |
726 | break; | |
727 | case READING_U8: | |
728 | *(u8 *) (pl022->rx) = | |
729 | readw(SSP_DR(pl022->virtbase)) & 0xFFU; | |
730 | break; | |
731 | case READING_U16: | |
732 | *(u16 *) (pl022->rx) = | |
733 | (u16) readw(SSP_DR(pl022->virtbase)); | |
734 | break; | |
735 | case READING_U32: | |
736 | *(u32 *) (pl022->rx) = | |
737 | readl(SSP_DR(pl022->virtbase)); | |
738 | break; | |
739 | } | |
740 | pl022->rx += (pl022->cur_chip->n_bytes); | |
741 | pl022->exp_fifo_level--; | |
742 | } | |
743 | } | |
744 | /* | |
745 | * When we exit here the TX FIFO should be full and the RX FIFO | |
746 | * should be empty | |
747 | */ | |
748 | } | |
749 | ||
750 | /** | |
751 | * next_transfer - Move to the Next transfer in the current spi message | |
752 | * @pl022: SSP driver private data structure | |
753 | * | |
754 | * This function moves though the linked list of spi transfers in the | |
755 | * current spi message and returns with the state of current spi | |
756 | * message i.e whether its last transfer is done(STATE_DONE) or | |
757 | * Next transfer is ready(STATE_RUNNING) | |
758 | */ | |
759 | static void *next_transfer(struct pl022 *pl022) | |
760 | { | |
761 | struct spi_message *msg = pl022->cur_msg; | |
762 | struct spi_transfer *trans = pl022->cur_transfer; | |
763 | ||
764 | /* Move to next transfer */ | |
765 | if (trans->transfer_list.next != &msg->transfers) { | |
766 | pl022->cur_transfer = | |
767 | list_entry(trans->transfer_list.next, | |
768 | struct spi_transfer, transfer_list); | |
769 | return STATE_RUNNING; | |
770 | } | |
771 | return STATE_DONE; | |
772 | } | |
773 | ||
774 | /* | |
775 | * This DMA functionality is only compiled in if we have | |
776 | * access to the generic DMA devices/DMA engine. | |
777 | */ | |
778 | #ifdef CONFIG_DMA_ENGINE | |
779 | static void unmap_free_dma_scatter(struct pl022 *pl022) | |
780 | { | |
781 | /* Unmap and free the SG tables */ | |
782 | dma_unmap_sg(pl022->dma_tx_channel->device->dev, pl022->sgt_tx.sgl, | |
783 | pl022->sgt_tx.nents, DMA_TO_DEVICE); | |
784 | dma_unmap_sg(pl022->dma_rx_channel->device->dev, pl022->sgt_rx.sgl, | |
785 | pl022->sgt_rx.nents, DMA_FROM_DEVICE); | |
786 | sg_free_table(&pl022->sgt_rx); | |
787 | sg_free_table(&pl022->sgt_tx); | |
788 | } | |
789 | ||
790 | static void dma_callback(void *data) | |
791 | { | |
792 | struct pl022 *pl022 = data; | |
793 | struct spi_message *msg = pl022->cur_msg; | |
794 | ||
795 | BUG_ON(!pl022->sgt_rx.sgl); | |
796 | ||
797 | #ifdef VERBOSE_DEBUG | |
798 | /* | |
799 | * Optionally dump out buffers to inspect contents, this is | |
800 | * good if you want to convince yourself that the loopback | |
801 | * read/write contents are the same, when adopting to a new | |
802 | * DMA engine. | |
803 | */ | |
804 | { | |
805 | struct scatterlist *sg; | |
806 | unsigned int i; | |
807 | ||
808 | dma_sync_sg_for_cpu(&pl022->adev->dev, | |
809 | pl022->sgt_rx.sgl, | |
810 | pl022->sgt_rx.nents, | |
811 | DMA_FROM_DEVICE); | |
812 | ||
813 | for_each_sg(pl022->sgt_rx.sgl, sg, pl022->sgt_rx.nents, i) { | |
814 | dev_dbg(&pl022->adev->dev, "SPI RX SG ENTRY: %d", i); | |
815 | print_hex_dump(KERN_ERR, "SPI RX: ", | |
816 | DUMP_PREFIX_OFFSET, | |
817 | 16, | |
818 | 1, | |
819 | sg_virt(sg), | |
820 | sg_dma_len(sg), | |
821 | 1); | |
822 | } | |
823 | for_each_sg(pl022->sgt_tx.sgl, sg, pl022->sgt_tx.nents, i) { | |
824 | dev_dbg(&pl022->adev->dev, "SPI TX SG ENTRY: %d", i); | |
825 | print_hex_dump(KERN_ERR, "SPI TX: ", | |
826 | DUMP_PREFIX_OFFSET, | |
827 | 16, | |
828 | 1, | |
829 | sg_virt(sg), | |
830 | sg_dma_len(sg), | |
831 | 1); | |
832 | } | |
833 | } | |
834 | #endif | |
835 | ||
836 | unmap_free_dma_scatter(pl022); | |
837 | ||
838 | /* Update total bytes transferred */ | |
839 | msg->actual_length += pl022->cur_transfer->len; | |
840 | if (pl022->cur_transfer->cs_change) | |
841 | pl022->cur_chip-> | |
842 | cs_control(SSP_CHIP_DESELECT); | |
843 | ||
844 | /* Move to next transfer */ | |
845 | msg->state = next_transfer(pl022); | |
846 | tasklet_schedule(&pl022->pump_transfers); | |
847 | } | |
848 | ||
849 | static void setup_dma_scatter(struct pl022 *pl022, | |
850 | void *buffer, | |
851 | unsigned int length, | |
852 | struct sg_table *sgtab) | |
853 | { | |
854 | struct scatterlist *sg; | |
855 | int bytesleft = length; | |
856 | void *bufp = buffer; | |
857 | int mapbytes; | |
858 | int i; | |
859 | ||
860 | if (buffer) { | |
861 | for_each_sg(sgtab->sgl, sg, sgtab->nents, i) { | |
862 | /* | |
863 | * If there are less bytes left than what fits | |
864 | * in the current page (plus page alignment offset) | |
865 | * we just feed in this, else we stuff in as much | |
866 | * as we can. | |
867 | */ | |
868 | if (bytesleft < (PAGE_SIZE - offset_in_page(bufp))) | |
869 | mapbytes = bytesleft; | |
870 | else | |
871 | mapbytes = PAGE_SIZE - offset_in_page(bufp); | |
872 | sg_set_page(sg, virt_to_page(bufp), | |
873 | mapbytes, offset_in_page(bufp)); | |
874 | bufp += mapbytes; | |
875 | bytesleft -= mapbytes; | |
876 | dev_dbg(&pl022->adev->dev, | |
877 | "set RX/TX target page @ %p, %d bytes, %d left\n", | |
878 | bufp, mapbytes, bytesleft); | |
879 | } | |
880 | } else { | |
881 | /* Map the dummy buffer on every page */ | |
882 | for_each_sg(sgtab->sgl, sg, sgtab->nents, i) { | |
883 | if (bytesleft < PAGE_SIZE) | |
884 | mapbytes = bytesleft; | |
885 | else | |
886 | mapbytes = PAGE_SIZE; | |
887 | sg_set_page(sg, virt_to_page(pl022->dummypage), | |
888 | mapbytes, 0); | |
889 | bytesleft -= mapbytes; | |
890 | dev_dbg(&pl022->adev->dev, | |
891 | "set RX/TX to dummy page %d bytes, %d left\n", | |
892 | mapbytes, bytesleft); | |
893 | ||
894 | } | |
895 | } | |
896 | BUG_ON(bytesleft); | |
897 | } | |
898 | ||
899 | /** | |
900 | * configure_dma - configures the channels for the next transfer | |
901 | * @pl022: SSP driver's private data structure | |
902 | */ | |
903 | static int configure_dma(struct pl022 *pl022) | |
904 | { | |
905 | struct dma_slave_config rx_conf = { | |
906 | .src_addr = SSP_DR(pl022->phybase), | |
907 | .direction = DMA_FROM_DEVICE, | |
908 | }; | |
909 | struct dma_slave_config tx_conf = { | |
910 | .dst_addr = SSP_DR(pl022->phybase), | |
911 | .direction = DMA_TO_DEVICE, | |
912 | }; | |
913 | unsigned int pages; | |
914 | int ret; | |
915 | int rx_sglen, tx_sglen; | |
916 | struct dma_chan *rxchan = pl022->dma_rx_channel; | |
917 | struct dma_chan *txchan = pl022->dma_tx_channel; | |
918 | struct dma_async_tx_descriptor *rxdesc; | |
919 | struct dma_async_tx_descriptor *txdesc; | |
920 | ||
921 | /* Check that the channels are available */ | |
922 | if (!rxchan || !txchan) | |
923 | return -ENODEV; | |
924 | ||
925 | /* | |
926 | * If supplied, the DMA burstsize should equal the FIFO trigger level. | |
927 | * Notice that the DMA engine uses one-to-one mapping. Since we can | |
928 | * not trigger on 2 elements this needs explicit mapping rather than | |
929 | * calculation. | |
930 | */ | |
931 | switch (pl022->rx_lev_trig) { | |
932 | case SSP_RX_1_OR_MORE_ELEM: | |
933 | rx_conf.src_maxburst = 1; | |
934 | break; | |
935 | case SSP_RX_4_OR_MORE_ELEM: | |
936 | rx_conf.src_maxburst = 4; | |
937 | break; | |
938 | case SSP_RX_8_OR_MORE_ELEM: | |
939 | rx_conf.src_maxburst = 8; | |
940 | break; | |
941 | case SSP_RX_16_OR_MORE_ELEM: | |
942 | rx_conf.src_maxburst = 16; | |
943 | break; | |
944 | case SSP_RX_32_OR_MORE_ELEM: | |
945 | rx_conf.src_maxburst = 32; | |
946 | break; | |
947 | default: | |
948 | rx_conf.src_maxburst = pl022->vendor->fifodepth >> 1; | |
949 | break; | |
950 | } | |
951 | ||
952 | switch (pl022->tx_lev_trig) { | |
953 | case SSP_TX_1_OR_MORE_EMPTY_LOC: | |
954 | tx_conf.dst_maxburst = 1; | |
955 | break; | |
956 | case SSP_TX_4_OR_MORE_EMPTY_LOC: | |
957 | tx_conf.dst_maxburst = 4; | |
958 | break; | |
959 | case SSP_TX_8_OR_MORE_EMPTY_LOC: | |
960 | tx_conf.dst_maxburst = 8; | |
961 | break; | |
962 | case SSP_TX_16_OR_MORE_EMPTY_LOC: | |
963 | tx_conf.dst_maxburst = 16; | |
964 | break; | |
965 | case SSP_TX_32_OR_MORE_EMPTY_LOC: | |
966 | tx_conf.dst_maxburst = 32; | |
967 | break; | |
968 | default: | |
969 | tx_conf.dst_maxburst = pl022->vendor->fifodepth >> 1; | |
970 | break; | |
971 | } | |
972 | ||
973 | switch (pl022->read) { | |
974 | case READING_NULL: | |
975 | /* Use the same as for writing */ | |
976 | rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED; | |
977 | break; | |
978 | case READING_U8: | |
979 | rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; | |
980 | break; | |
981 | case READING_U16: | |
982 | rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES; | |
983 | break; | |
984 | case READING_U32: | |
985 | rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; | |
986 | break; | |
987 | } | |
988 | ||
989 | switch (pl022->write) { | |
990 | case WRITING_NULL: | |
991 | /* Use the same as for reading */ | |
992 | tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED; | |
993 | break; | |
994 | case WRITING_U8: | |
995 | tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; | |
996 | break; | |
997 | case WRITING_U16: | |
998 | tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES; | |
999 | break; | |
1000 | case WRITING_U32: | |
1001 | tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; | |
1002 | break; | |
1003 | } | |
1004 | ||
1005 | /* SPI pecularity: we need to read and write the same width */ | |
1006 | if (rx_conf.src_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED) | |
1007 | rx_conf.src_addr_width = tx_conf.dst_addr_width; | |
1008 | if (tx_conf.dst_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED) | |
1009 | tx_conf.dst_addr_width = rx_conf.src_addr_width; | |
1010 | BUG_ON(rx_conf.src_addr_width != tx_conf.dst_addr_width); | |
1011 | ||
1012 | dmaengine_slave_config(rxchan, &rx_conf); | |
1013 | dmaengine_slave_config(txchan, &tx_conf); | |
1014 | ||
1015 | /* Create sglists for the transfers */ | |
1016 | pages = DIV_ROUND_UP(pl022->cur_transfer->len, PAGE_SIZE); | |
1017 | dev_dbg(&pl022->adev->dev, "using %d pages for transfer\n", pages); | |
1018 | ||
1019 | ret = sg_alloc_table(&pl022->sgt_rx, pages, GFP_ATOMIC); | |
1020 | if (ret) | |
1021 | goto err_alloc_rx_sg; | |
1022 | ||
1023 | ret = sg_alloc_table(&pl022->sgt_tx, pages, GFP_ATOMIC); | |
1024 | if (ret) | |
1025 | goto err_alloc_tx_sg; | |
1026 | ||
1027 | /* Fill in the scatterlists for the RX+TX buffers */ | |
1028 | setup_dma_scatter(pl022, pl022->rx, | |
1029 | pl022->cur_transfer->len, &pl022->sgt_rx); | |
1030 | setup_dma_scatter(pl022, pl022->tx, | |
1031 | pl022->cur_transfer->len, &pl022->sgt_tx); | |
1032 | ||
1033 | /* Map DMA buffers */ | |
1034 | rx_sglen = dma_map_sg(rxchan->device->dev, pl022->sgt_rx.sgl, | |
1035 | pl022->sgt_rx.nents, DMA_FROM_DEVICE); | |
1036 | if (!rx_sglen) | |
1037 | goto err_rx_sgmap; | |
1038 | ||
1039 | tx_sglen = dma_map_sg(txchan->device->dev, pl022->sgt_tx.sgl, | |
1040 | pl022->sgt_tx.nents, DMA_TO_DEVICE); | |
1041 | if (!tx_sglen) | |
1042 | goto err_tx_sgmap; | |
1043 | ||
1044 | /* Send both scatterlists */ | |
1045 | rxdesc = rxchan->device->device_prep_slave_sg(rxchan, | |
1046 | pl022->sgt_rx.sgl, | |
1047 | rx_sglen, | |
1048 | DMA_FROM_DEVICE, | |
1049 | DMA_PREP_INTERRUPT | DMA_CTRL_ACK); | |
1050 | if (!rxdesc) | |
1051 | goto err_rxdesc; | |
1052 | ||
1053 | txdesc = txchan->device->device_prep_slave_sg(txchan, | |
1054 | pl022->sgt_tx.sgl, | |
1055 | tx_sglen, | |
1056 | DMA_TO_DEVICE, | |
1057 | DMA_PREP_INTERRUPT | DMA_CTRL_ACK); | |
1058 | if (!txdesc) | |
1059 | goto err_txdesc; | |
1060 | ||
1061 | /* Put the callback on the RX transfer only, that should finish last */ | |
1062 | rxdesc->callback = dma_callback; | |
1063 | rxdesc->callback_param = pl022; | |
1064 | ||
1065 | /* Submit and fire RX and TX with TX last so we're ready to read! */ | |
1066 | dmaengine_submit(rxdesc); | |
1067 | dmaengine_submit(txdesc); | |
1068 | dma_async_issue_pending(rxchan); | |
1069 | dma_async_issue_pending(txchan); | |
1070 | ||
1071 | return 0; | |
1072 | ||
1073 | err_txdesc: | |
1074 | dmaengine_terminate_all(txchan); | |
1075 | err_rxdesc: | |
1076 | dmaengine_terminate_all(rxchan); | |
1077 | dma_unmap_sg(txchan->device->dev, pl022->sgt_tx.sgl, | |
1078 | pl022->sgt_tx.nents, DMA_TO_DEVICE); | |
1079 | err_tx_sgmap: | |
1080 | dma_unmap_sg(rxchan->device->dev, pl022->sgt_rx.sgl, | |
1081 | pl022->sgt_tx.nents, DMA_FROM_DEVICE); | |
1082 | err_rx_sgmap: | |
1083 | sg_free_table(&pl022->sgt_tx); | |
1084 | err_alloc_tx_sg: | |
1085 | sg_free_table(&pl022->sgt_rx); | |
1086 | err_alloc_rx_sg: | |
1087 | return -ENOMEM; | |
1088 | } | |
1089 | ||
1090 | static int __init pl022_dma_probe(struct pl022 *pl022) | |
1091 | { | |
1092 | dma_cap_mask_t mask; | |
1093 | ||
1094 | /* Try to acquire a generic DMA engine slave channel */ | |
1095 | dma_cap_zero(mask); | |
1096 | dma_cap_set(DMA_SLAVE, mask); | |
1097 | /* | |
1098 | * We need both RX and TX channels to do DMA, else do none | |
1099 | * of them. | |
1100 | */ | |
1101 | pl022->dma_rx_channel = dma_request_channel(mask, | |
1102 | pl022->master_info->dma_filter, | |
1103 | pl022->master_info->dma_rx_param); | |
1104 | if (!pl022->dma_rx_channel) { | |
1105 | dev_dbg(&pl022->adev->dev, "no RX DMA channel!\n"); | |
1106 | goto err_no_rxchan; | |
1107 | } | |
1108 | ||
1109 | pl022->dma_tx_channel = dma_request_channel(mask, | |
1110 | pl022->master_info->dma_filter, | |
1111 | pl022->master_info->dma_tx_param); | |
1112 | if (!pl022->dma_tx_channel) { | |
1113 | dev_dbg(&pl022->adev->dev, "no TX DMA channel!\n"); | |
1114 | goto err_no_txchan; | |
1115 | } | |
1116 | ||
1117 | pl022->dummypage = kmalloc(PAGE_SIZE, GFP_KERNEL); | |
1118 | if (!pl022->dummypage) { | |
1119 | dev_dbg(&pl022->adev->dev, "no DMA dummypage!\n"); | |
1120 | goto err_no_dummypage; | |
1121 | } | |
1122 | ||
1123 | dev_info(&pl022->adev->dev, "setup for DMA on RX %s, TX %s\n", | |
1124 | dma_chan_name(pl022->dma_rx_channel), | |
1125 | dma_chan_name(pl022->dma_tx_channel)); | |
1126 | ||
1127 | return 0; | |
1128 | ||
1129 | err_no_dummypage: | |
1130 | dma_release_channel(pl022->dma_tx_channel); | |
1131 | err_no_txchan: | |
1132 | dma_release_channel(pl022->dma_rx_channel); | |
1133 | pl022->dma_rx_channel = NULL; | |
1134 | err_no_rxchan: | |
1135 | dev_err(&pl022->adev->dev, | |
1136 | "Failed to work in dma mode, work without dma!\n"); | |
1137 | return -ENODEV; | |
1138 | } | |
1139 | ||
1140 | static void terminate_dma(struct pl022 *pl022) | |
1141 | { | |
1142 | struct dma_chan *rxchan = pl022->dma_rx_channel; | |
1143 | struct dma_chan *txchan = pl022->dma_tx_channel; | |
1144 | ||
1145 | dmaengine_terminate_all(rxchan); | |
1146 | dmaengine_terminate_all(txchan); | |
1147 | unmap_free_dma_scatter(pl022); | |
1148 | } | |
1149 | ||
1150 | static void pl022_dma_remove(struct pl022 *pl022) | |
1151 | { | |
1152 | if (pl022->busy) | |
1153 | terminate_dma(pl022); | |
1154 | if (pl022->dma_tx_channel) | |
1155 | dma_release_channel(pl022->dma_tx_channel); | |
1156 | if (pl022->dma_rx_channel) | |
1157 | dma_release_channel(pl022->dma_rx_channel); | |
1158 | kfree(pl022->dummypage); | |
1159 | } | |
1160 | ||
1161 | #else | |
1162 | static inline int configure_dma(struct pl022 *pl022) | |
1163 | { | |
1164 | return -ENODEV; | |
1165 | } | |
1166 | ||
1167 | static inline int pl022_dma_probe(struct pl022 *pl022) | |
1168 | { | |
1169 | return 0; | |
1170 | } | |
1171 | ||
1172 | static inline void pl022_dma_remove(struct pl022 *pl022) | |
1173 | { | |
1174 | } | |
1175 | #endif | |
1176 | ||
1177 | /** | |
1178 | * pl022_interrupt_handler - Interrupt handler for SSP controller | |
1179 | * | |
1180 | * This function handles interrupts generated for an interrupt based transfer. | |
1181 | * If a receive overrun (ROR) interrupt is there then we disable SSP, flag the | |
1182 | * current message's state as STATE_ERROR and schedule the tasklet | |
1183 | * pump_transfers which will do the postprocessing of the current message by | |
1184 | * calling giveback(). Otherwise it reads data from RX FIFO till there is no | |
1185 | * more data, and writes data in TX FIFO till it is not full. If we complete | |
1186 | * the transfer we move to the next transfer and schedule the tasklet. | |
1187 | */ | |
1188 | static irqreturn_t pl022_interrupt_handler(int irq, void *dev_id) | |
1189 | { | |
1190 | struct pl022 *pl022 = dev_id; | |
1191 | struct spi_message *msg = pl022->cur_msg; | |
1192 | u16 irq_status = 0; | |
1193 | u16 flag = 0; | |
1194 | ||
1195 | if (unlikely(!msg)) { | |
1196 | dev_err(&pl022->adev->dev, | |
1197 | "bad message state in interrupt handler"); | |
1198 | /* Never fail */ | |
1199 | return IRQ_HANDLED; | |
1200 | } | |
1201 | ||
1202 | /* Read the Interrupt Status Register */ | |
1203 | irq_status = readw(SSP_MIS(pl022->virtbase)); | |
1204 | ||
1205 | if (unlikely(!irq_status)) | |
1206 | return IRQ_NONE; | |
1207 | ||
1208 | /* | |
1209 | * This handles the FIFO interrupts, the timeout | |
1210 | * interrupts are flatly ignored, they cannot be | |
1211 | * trusted. | |
1212 | */ | |
1213 | if (unlikely(irq_status & SSP_MIS_MASK_RORMIS)) { | |
1214 | /* | |
1215 | * Overrun interrupt - bail out since our Data has been | |
1216 | * corrupted | |
1217 | */ | |
1218 | dev_err(&pl022->adev->dev, "FIFO overrun\n"); | |
1219 | if (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RFF) | |
1220 | dev_err(&pl022->adev->dev, | |
1221 | "RXFIFO is full\n"); | |
1222 | if (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_TNF) | |
1223 | dev_err(&pl022->adev->dev, | |
1224 | "TXFIFO is full\n"); | |
1225 | ||
1226 | /* | |
1227 | * Disable and clear interrupts, disable SSP, | |
1228 | * mark message with bad status so it can be | |
1229 | * retried. | |
1230 | */ | |
1231 | writew(DISABLE_ALL_INTERRUPTS, | |
1232 | SSP_IMSC(pl022->virtbase)); | |
1233 | writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase)); | |
1234 | writew((readw(SSP_CR1(pl022->virtbase)) & | |
1235 | (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase)); | |
1236 | msg->state = STATE_ERROR; | |
1237 | ||
1238 | /* Schedule message queue handler */ | |
1239 | tasklet_schedule(&pl022->pump_transfers); | |
1240 | return IRQ_HANDLED; | |
1241 | } | |
1242 | ||
1243 | readwriter(pl022); | |
1244 | ||
1245 | if ((pl022->tx == pl022->tx_end) && (flag == 0)) { | |
1246 | flag = 1; | |
1247 | /* Disable Transmit interrupt, enable receive interrupt */ | |
1248 | writew((readw(SSP_IMSC(pl022->virtbase)) & | |
1249 | ~SSP_IMSC_MASK_TXIM) | SSP_IMSC_MASK_RXIM, | |
1250 | SSP_IMSC(pl022->virtbase)); | |
1251 | } | |
1252 | ||
1253 | /* | |
1254 | * Since all transactions must write as much as shall be read, | |
1255 | * we can conclude the entire transaction once RX is complete. | |
1256 | * At this point, all TX will always be finished. | |
1257 | */ | |
1258 | if (pl022->rx >= pl022->rx_end) { | |
1259 | writew(DISABLE_ALL_INTERRUPTS, | |
1260 | SSP_IMSC(pl022->virtbase)); | |
1261 | writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase)); | |
1262 | if (unlikely(pl022->rx > pl022->rx_end)) { | |
1263 | dev_warn(&pl022->adev->dev, "read %u surplus " | |
1264 | "bytes (did you request an odd " | |
1265 | "number of bytes on a 16bit bus?)\n", | |
1266 | (u32) (pl022->rx - pl022->rx_end)); | |
1267 | } | |
1268 | /* Update total bytes transferred */ | |
1269 | msg->actual_length += pl022->cur_transfer->len; | |
1270 | if (pl022->cur_transfer->cs_change) | |
1271 | pl022->cur_chip-> | |
1272 | cs_control(SSP_CHIP_DESELECT); | |
1273 | /* Move to next transfer */ | |
1274 | msg->state = next_transfer(pl022); | |
1275 | tasklet_schedule(&pl022->pump_transfers); | |
1276 | return IRQ_HANDLED; | |
1277 | } | |
1278 | ||
1279 | return IRQ_HANDLED; | |
1280 | } | |
1281 | ||
1282 | /** | |
1283 | * This sets up the pointers to memory for the next message to | |
1284 | * send out on the SPI bus. | |
1285 | */ | |
1286 | static int set_up_next_transfer(struct pl022 *pl022, | |
1287 | struct spi_transfer *transfer) | |
1288 | { | |
1289 | int residue; | |
1290 | ||
1291 | /* Sanity check the message for this bus width */ | |
1292 | residue = pl022->cur_transfer->len % pl022->cur_chip->n_bytes; | |
1293 | if (unlikely(residue != 0)) { | |
1294 | dev_err(&pl022->adev->dev, | |
1295 | "message of %u bytes to transmit but the current " | |
1296 | "chip bus has a data width of %u bytes!\n", | |
1297 | pl022->cur_transfer->len, | |
1298 | pl022->cur_chip->n_bytes); | |
1299 | dev_err(&pl022->adev->dev, "skipping this message\n"); | |
1300 | return -EIO; | |
1301 | } | |
1302 | pl022->tx = (void *)transfer->tx_buf; | |
1303 | pl022->tx_end = pl022->tx + pl022->cur_transfer->len; | |
1304 | pl022->rx = (void *)transfer->rx_buf; | |
1305 | pl022->rx_end = pl022->rx + pl022->cur_transfer->len; | |
1306 | pl022->write = | |
1307 | pl022->tx ? pl022->cur_chip->write : WRITING_NULL; | |
1308 | pl022->read = pl022->rx ? pl022->cur_chip->read : READING_NULL; | |
1309 | return 0; | |
1310 | } | |
1311 | ||
1312 | /** | |
1313 | * pump_transfers - Tasklet function which schedules next transfer | |
1314 | * when running in interrupt or DMA transfer mode. | |
1315 | * @data: SSP driver private data structure | |
1316 | * | |
1317 | */ | |
1318 | static void pump_transfers(unsigned long data) | |
1319 | { | |
1320 | struct pl022 *pl022 = (struct pl022 *) data; | |
1321 | struct spi_message *message = NULL; | |
1322 | struct spi_transfer *transfer = NULL; | |
1323 | struct spi_transfer *previous = NULL; | |
1324 | ||
1325 | /* Get current state information */ | |
1326 | message = pl022->cur_msg; | |
1327 | transfer = pl022->cur_transfer; | |
1328 | ||
1329 | /* Handle for abort */ | |
1330 | if (message->state == STATE_ERROR) { | |
1331 | message->status = -EIO; | |
1332 | giveback(pl022); | |
1333 | return; | |
1334 | } | |
1335 | ||
1336 | /* Handle end of message */ | |
1337 | if (message->state == STATE_DONE) { | |
1338 | message->status = 0; | |
1339 | giveback(pl022); | |
1340 | return; | |
1341 | } | |
1342 | ||
1343 | /* Delay if requested at end of transfer before CS change */ | |
1344 | if (message->state == STATE_RUNNING) { | |
1345 | previous = list_entry(transfer->transfer_list.prev, | |
1346 | struct spi_transfer, | |
1347 | transfer_list); | |
1348 | if (previous->delay_usecs) | |
1349 | /* | |
1350 | * FIXME: This runs in interrupt context. | |
1351 | * Is this really smart? | |
1352 | */ | |
1353 | udelay(previous->delay_usecs); | |
1354 | ||
1355 | /* Drop chip select only if cs_change is requested */ | |
1356 | if (previous->cs_change) | |
1357 | pl022->cur_chip->cs_control(SSP_CHIP_SELECT); | |
1358 | } else { | |
1359 | /* STATE_START */ | |
1360 | message->state = STATE_RUNNING; | |
1361 | } | |
1362 | ||
1363 | if (set_up_next_transfer(pl022, transfer)) { | |
1364 | message->state = STATE_ERROR; | |
1365 | message->status = -EIO; | |
1366 | giveback(pl022); | |
1367 | return; | |
1368 | } | |
1369 | /* Flush the FIFOs and let's go! */ | |
1370 | flush(pl022); | |
1371 | ||
1372 | if (pl022->cur_chip->enable_dma) { | |
1373 | if (configure_dma(pl022)) { | |
1374 | dev_dbg(&pl022->adev->dev, | |
1375 | "configuration of DMA failed, fall back to interrupt mode\n"); | |
1376 | goto err_config_dma; | |
1377 | } | |
1378 | return; | |
1379 | } | |
1380 | ||
1381 | err_config_dma: | |
1382 | /* enable all interrupts except RX */ | |
1383 | writew(ENABLE_ALL_INTERRUPTS & ~SSP_IMSC_MASK_RXIM, SSP_IMSC(pl022->virtbase)); | |
1384 | } | |
1385 | ||
1386 | static void do_interrupt_dma_transfer(struct pl022 *pl022) | |
1387 | { | |
1388 | /* | |
1389 | * Default is to enable all interrupts except RX - | |
1390 | * this will be enabled once TX is complete | |
1391 | */ | |
1392 | u32 irqflags = ENABLE_ALL_INTERRUPTS & ~SSP_IMSC_MASK_RXIM; | |
1393 | ||
1394 | /* Enable target chip */ | |
1395 | pl022->cur_chip->cs_control(SSP_CHIP_SELECT); | |
1396 | if (set_up_next_transfer(pl022, pl022->cur_transfer)) { | |
1397 | /* Error path */ | |
1398 | pl022->cur_msg->state = STATE_ERROR; | |
1399 | pl022->cur_msg->status = -EIO; | |
1400 | giveback(pl022); | |
1401 | return; | |
1402 | } | |
1403 | /* If we're using DMA, set up DMA here */ | |
1404 | if (pl022->cur_chip->enable_dma) { | |
1405 | /* Configure DMA transfer */ | |
1406 | if (configure_dma(pl022)) { | |
1407 | dev_dbg(&pl022->adev->dev, | |
1408 | "configuration of DMA failed, fall back to interrupt mode\n"); | |
1409 | goto err_config_dma; | |
1410 | } | |
1411 | /* Disable interrupts in DMA mode, IRQ from DMA controller */ | |
1412 | irqflags = DISABLE_ALL_INTERRUPTS; | |
1413 | } | |
1414 | err_config_dma: | |
1415 | /* Enable SSP, turn on interrupts */ | |
1416 | writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE), | |
1417 | SSP_CR1(pl022->virtbase)); | |
1418 | writew(irqflags, SSP_IMSC(pl022->virtbase)); | |
1419 | } | |
1420 | ||
1421 | static void do_polling_transfer(struct pl022 *pl022) | |
1422 | { | |
1423 | struct spi_message *message = NULL; | |
1424 | struct spi_transfer *transfer = NULL; | |
1425 | struct spi_transfer *previous = NULL; | |
1426 | struct chip_data *chip; | |
1427 | unsigned long time, timeout; | |
1428 | ||
1429 | chip = pl022->cur_chip; | |
1430 | message = pl022->cur_msg; | |
1431 | ||
1432 | while (message->state != STATE_DONE) { | |
1433 | /* Handle for abort */ | |
1434 | if (message->state == STATE_ERROR) | |
1435 | break; | |
1436 | transfer = pl022->cur_transfer; | |
1437 | ||
1438 | /* Delay if requested at end of transfer */ | |
1439 | if (message->state == STATE_RUNNING) { | |
1440 | previous = | |
1441 | list_entry(transfer->transfer_list.prev, | |
1442 | struct spi_transfer, transfer_list); | |
1443 | if (previous->delay_usecs) | |
1444 | udelay(previous->delay_usecs); | |
1445 | if (previous->cs_change) | |
1446 | pl022->cur_chip->cs_control(SSP_CHIP_SELECT); | |
1447 | } else { | |
1448 | /* STATE_START */ | |
1449 | message->state = STATE_RUNNING; | |
1450 | pl022->cur_chip->cs_control(SSP_CHIP_SELECT); | |
1451 | } | |
1452 | ||
1453 | /* Configuration Changing Per Transfer */ | |
1454 | if (set_up_next_transfer(pl022, transfer)) { | |
1455 | /* Error path */ | |
1456 | message->state = STATE_ERROR; | |
1457 | break; | |
1458 | } | |
1459 | /* Flush FIFOs and enable SSP */ | |
1460 | flush(pl022); | |
1461 | writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE), | |
1462 | SSP_CR1(pl022->virtbase)); | |
1463 | ||
1464 | dev_dbg(&pl022->adev->dev, "polling transfer ongoing ...\n"); | |
1465 | ||
1466 | timeout = jiffies + msecs_to_jiffies(SPI_POLLING_TIMEOUT); | |
1467 | while (pl022->tx < pl022->tx_end || pl022->rx < pl022->rx_end) { | |
1468 | time = jiffies; | |
1469 | readwriter(pl022); | |
1470 | if (time_after(time, timeout)) { | |
1471 | dev_warn(&pl022->adev->dev, | |
1472 | "%s: timeout!\n", __func__); | |
1473 | message->state = STATE_ERROR; | |
1474 | goto out; | |
1475 | } | |
1476 | cpu_relax(); | |
1477 | } | |
1478 | ||
1479 | /* Update total byte transferred */ | |
1480 | message->actual_length += pl022->cur_transfer->len; | |
1481 | if (pl022->cur_transfer->cs_change) | |
1482 | pl022->cur_chip->cs_control(SSP_CHIP_DESELECT); | |
1483 | /* Move to next transfer */ | |
1484 | message->state = next_transfer(pl022); | |
1485 | } | |
1486 | out: | |
1487 | /* Handle end of message */ | |
1488 | if (message->state == STATE_DONE) | |
1489 | message->status = 0; | |
1490 | else | |
1491 | message->status = -EIO; | |
1492 | ||
1493 | giveback(pl022); | |
1494 | return; | |
1495 | } | |
1496 | ||
1497 | /** | |
1498 | * pump_messages - Workqueue function which processes spi message queue | |
1499 | * @data: pointer to private data of SSP driver | |
1500 | * | |
1501 | * This function checks if there is any spi message in the queue that | |
1502 | * needs processing and delegate control to appropriate function | |
1503 | * do_polling_transfer()/do_interrupt_dma_transfer() | |
1504 | * based on the kind of the transfer | |
1505 | * | |
1506 | */ | |
1507 | static void pump_messages(struct work_struct *work) | |
1508 | { | |
1509 | struct pl022 *pl022 = | |
1510 | container_of(work, struct pl022, pump_messages); | |
1511 | unsigned long flags; | |
1512 | ||
1513 | /* Lock queue and check for queue work */ | |
1514 | spin_lock_irqsave(&pl022->queue_lock, flags); | |
1515 | if (list_empty(&pl022->queue) || !pl022->running) { | |
1516 | pl022->busy = false; | |
1517 | spin_unlock_irqrestore(&pl022->queue_lock, flags); | |
1518 | return; | |
1519 | } | |
1520 | /* Make sure we are not already running a message */ | |
1521 | if (pl022->cur_msg) { | |
1522 | spin_unlock_irqrestore(&pl022->queue_lock, flags); | |
1523 | return; | |
1524 | } | |
1525 | /* Extract head of queue */ | |
1526 | pl022->cur_msg = | |
1527 | list_entry(pl022->queue.next, struct spi_message, queue); | |
1528 | ||
1529 | list_del_init(&pl022->cur_msg->queue); | |
1530 | pl022->busy = true; | |
1531 | spin_unlock_irqrestore(&pl022->queue_lock, flags); | |
1532 | ||
1533 | /* Initial message state */ | |
1534 | pl022->cur_msg->state = STATE_START; | |
1535 | pl022->cur_transfer = list_entry(pl022->cur_msg->transfers.next, | |
1536 | struct spi_transfer, transfer_list); | |
1537 | ||
1538 | /* Setup the SPI using the per chip configuration */ | |
1539 | pl022->cur_chip = spi_get_ctldata(pl022->cur_msg->spi); | |
1540 | /* | |
1541 | * We enable the core voltage and clocks here, then the clocks | |
1542 | * and core will be disabled when giveback() is called in each method | |
1543 | * (poll/interrupt/DMA) | |
1544 | */ | |
1545 | pm_runtime_get_sync(&pl022->adev->dev); | |
1546 | restore_state(pl022); | |
1547 | flush(pl022); | |
1548 | ||
1549 | if (pl022->cur_chip->xfer_type == POLLING_TRANSFER) | |
1550 | do_polling_transfer(pl022); | |
1551 | else | |
1552 | do_interrupt_dma_transfer(pl022); | |
1553 | } | |
1554 | ||
1555 | static int __init init_queue(struct pl022 *pl022) | |
1556 | { | |
1557 | INIT_LIST_HEAD(&pl022->queue); | |
1558 | spin_lock_init(&pl022->queue_lock); | |
1559 | ||
1560 | pl022->running = false; | |
1561 | pl022->busy = false; | |
1562 | ||
1563 | tasklet_init(&pl022->pump_transfers, pump_transfers, | |
1564 | (unsigned long)pl022); | |
1565 | ||
1566 | INIT_WORK(&pl022->pump_messages, pump_messages); | |
1567 | pl022->workqueue = create_singlethread_workqueue( | |
1568 | dev_name(pl022->master->dev.parent)); | |
1569 | if (pl022->workqueue == NULL) | |
1570 | return -EBUSY; | |
1571 | ||
1572 | return 0; | |
1573 | } | |
1574 | ||
1575 | static int start_queue(struct pl022 *pl022) | |
1576 | { | |
1577 | unsigned long flags; | |
1578 | ||
1579 | spin_lock_irqsave(&pl022->queue_lock, flags); | |
1580 | ||
1581 | if (pl022->running || pl022->busy) { | |
1582 | spin_unlock_irqrestore(&pl022->queue_lock, flags); | |
1583 | return -EBUSY; | |
1584 | } | |
1585 | ||
1586 | pl022->running = true; | |
1587 | pl022->cur_msg = NULL; | |
1588 | pl022->cur_transfer = NULL; | |
1589 | pl022->cur_chip = NULL; | |
1590 | spin_unlock_irqrestore(&pl022->queue_lock, flags); | |
1591 | ||
1592 | queue_work(pl022->workqueue, &pl022->pump_messages); | |
1593 | ||
1594 | return 0; | |
1595 | } | |
1596 | ||
1597 | static int stop_queue(struct pl022 *pl022) | |
1598 | { | |
1599 | unsigned long flags; | |
1600 | unsigned limit = 500; | |
1601 | int status = 0; | |
1602 | ||
1603 | spin_lock_irqsave(&pl022->queue_lock, flags); | |
1604 | ||
1605 | /* This is a bit lame, but is optimized for the common execution path. | |
1606 | * A wait_queue on the pl022->busy could be used, but then the common | |
1607 | * execution path (pump_messages) would be required to call wake_up or | |
1608 | * friends on every SPI message. Do this instead */ | |
1609 | while ((!list_empty(&pl022->queue) || pl022->busy) && limit--) { | |
1610 | spin_unlock_irqrestore(&pl022->queue_lock, flags); | |
1611 | msleep(10); | |
1612 | spin_lock_irqsave(&pl022->queue_lock, flags); | |
1613 | } | |
1614 | ||
1615 | if (!list_empty(&pl022->queue) || pl022->busy) | |
1616 | status = -EBUSY; | |
1617 | else | |
1618 | pl022->running = false; | |
1619 | ||
1620 | spin_unlock_irqrestore(&pl022->queue_lock, flags); | |
1621 | ||
1622 | return status; | |
1623 | } | |
1624 | ||
1625 | static int destroy_queue(struct pl022 *pl022) | |
1626 | { | |
1627 | int status; | |
1628 | ||
1629 | status = stop_queue(pl022); | |
1630 | /* we are unloading the module or failing to load (only two calls | |
1631 | * to this routine), and neither call can handle a return value. | |
1632 | * However, destroy_workqueue calls flush_workqueue, and that will | |
1633 | * block until all work is done. If the reason that stop_queue | |
1634 | * timed out is that the work will never finish, then it does no | |
1635 | * good to call destroy_workqueue, so return anyway. */ | |
1636 | if (status != 0) | |
1637 | return status; | |
1638 | ||
1639 | destroy_workqueue(pl022->workqueue); | |
1640 | ||
1641 | return 0; | |
1642 | } | |
1643 | ||
1644 | static int verify_controller_parameters(struct pl022 *pl022, | |
1645 | struct pl022_config_chip const *chip_info) | |
1646 | { | |
1647 | if ((chip_info->iface < SSP_INTERFACE_MOTOROLA_SPI) | |
1648 | || (chip_info->iface > SSP_INTERFACE_UNIDIRECTIONAL)) { | |
1649 | dev_err(&pl022->adev->dev, | |
1650 | "interface is configured incorrectly\n"); | |
1651 | return -EINVAL; | |
1652 | } | |
1653 | if ((chip_info->iface == SSP_INTERFACE_UNIDIRECTIONAL) && | |
1654 | (!pl022->vendor->unidir)) { | |
1655 | dev_err(&pl022->adev->dev, | |
1656 | "unidirectional mode not supported in this " | |
1657 | "hardware version\n"); | |
1658 | return -EINVAL; | |
1659 | } | |
1660 | if ((chip_info->hierarchy != SSP_MASTER) | |
1661 | && (chip_info->hierarchy != SSP_SLAVE)) { | |
1662 | dev_err(&pl022->adev->dev, | |
1663 | "hierarchy is configured incorrectly\n"); | |
1664 | return -EINVAL; | |
1665 | } | |
1666 | if ((chip_info->com_mode != INTERRUPT_TRANSFER) | |
1667 | && (chip_info->com_mode != DMA_TRANSFER) | |
1668 | && (chip_info->com_mode != POLLING_TRANSFER)) { | |
1669 | dev_err(&pl022->adev->dev, | |
1670 | "Communication mode is configured incorrectly\n"); | |
1671 | return -EINVAL; | |
1672 | } | |
1673 | switch (chip_info->rx_lev_trig) { | |
1674 | case SSP_RX_1_OR_MORE_ELEM: | |
1675 | case SSP_RX_4_OR_MORE_ELEM: | |
1676 | case SSP_RX_8_OR_MORE_ELEM: | |
1677 | /* These are always OK, all variants can handle this */ | |
1678 | break; | |
1679 | case SSP_RX_16_OR_MORE_ELEM: | |
1680 | if (pl022->vendor->fifodepth < 16) { | |
1681 | dev_err(&pl022->adev->dev, | |
1682 | "RX FIFO Trigger Level is configured incorrectly\n"); | |
1683 | return -EINVAL; | |
1684 | } | |
1685 | break; | |
1686 | case SSP_RX_32_OR_MORE_ELEM: | |
1687 | if (pl022->vendor->fifodepth < 32) { | |
1688 | dev_err(&pl022->adev->dev, | |
1689 | "RX FIFO Trigger Level is configured incorrectly\n"); | |
1690 | return -EINVAL; | |
1691 | } | |
1692 | break; | |
1693 | default: | |
1694 | dev_err(&pl022->adev->dev, | |
1695 | "RX FIFO Trigger Level is configured incorrectly\n"); | |
1696 | return -EINVAL; | |
1697 | break; | |
1698 | } | |
1699 | switch (chip_info->tx_lev_trig) { | |
1700 | case SSP_TX_1_OR_MORE_EMPTY_LOC: | |
1701 | case SSP_TX_4_OR_MORE_EMPTY_LOC: | |
1702 | case SSP_TX_8_OR_MORE_EMPTY_LOC: | |
1703 | /* These are always OK, all variants can handle this */ | |
1704 | break; | |
1705 | case SSP_TX_16_OR_MORE_EMPTY_LOC: | |
1706 | if (pl022->vendor->fifodepth < 16) { | |
1707 | dev_err(&pl022->adev->dev, | |
1708 | "TX FIFO Trigger Level is configured incorrectly\n"); | |
1709 | return -EINVAL; | |
1710 | } | |
1711 | break; | |
1712 | case SSP_TX_32_OR_MORE_EMPTY_LOC: | |
1713 | if (pl022->vendor->fifodepth < 32) { | |
1714 | dev_err(&pl022->adev->dev, | |
1715 | "TX FIFO Trigger Level is configured incorrectly\n"); | |
1716 | return -EINVAL; | |
1717 | } | |
1718 | break; | |
1719 | default: | |
1720 | dev_err(&pl022->adev->dev, | |
1721 | "TX FIFO Trigger Level is configured incorrectly\n"); | |
1722 | return -EINVAL; | |
1723 | break; | |
1724 | } | |
1725 | if (chip_info->iface == SSP_INTERFACE_NATIONAL_MICROWIRE) { | |
1726 | if ((chip_info->ctrl_len < SSP_BITS_4) | |
1727 | || (chip_info->ctrl_len > SSP_BITS_32)) { | |
1728 | dev_err(&pl022->adev->dev, | |
1729 | "CTRL LEN is configured incorrectly\n"); | |
1730 | return -EINVAL; | |
1731 | } | |
1732 | if ((chip_info->wait_state != SSP_MWIRE_WAIT_ZERO) | |
1733 | && (chip_info->wait_state != SSP_MWIRE_WAIT_ONE)) { | |
1734 | dev_err(&pl022->adev->dev, | |
1735 | "Wait State is configured incorrectly\n"); | |
1736 | return -EINVAL; | |
1737 | } | |
1738 | /* Half duplex is only available in the ST Micro version */ | |
1739 | if (pl022->vendor->extended_cr) { | |
1740 | if ((chip_info->duplex != | |
1741 | SSP_MICROWIRE_CHANNEL_FULL_DUPLEX) | |
1742 | && (chip_info->duplex != | |
1743 | SSP_MICROWIRE_CHANNEL_HALF_DUPLEX)) { | |
1744 | dev_err(&pl022->adev->dev, | |
1745 | "Microwire duplex mode is configured incorrectly\n"); | |
1746 | return -EINVAL; | |
1747 | } | |
1748 | } else { | |
1749 | if (chip_info->duplex != SSP_MICROWIRE_CHANNEL_FULL_DUPLEX) | |
1750 | dev_err(&pl022->adev->dev, | |
1751 | "Microwire half duplex mode requested," | |
1752 | " but this is only available in the" | |
1753 | " ST version of PL022\n"); | |
1754 | return -EINVAL; | |
1755 | } | |
1756 | } | |
1757 | return 0; | |
1758 | } | |
1759 | ||
1760 | /** | |
1761 | * pl022_transfer - transfer function registered to SPI master framework | |
1762 | * @spi: spi device which is requesting transfer | |
1763 | * @msg: spi message which is to handled is queued to driver queue | |
1764 | * | |
1765 | * This function is registered to the SPI framework for this SPI master | |
1766 | * controller. It will queue the spi_message in the queue of driver if | |
1767 | * the queue is not stopped and return. | |
1768 | */ | |
1769 | static int pl022_transfer(struct spi_device *spi, struct spi_message *msg) | |
1770 | { | |
1771 | struct pl022 *pl022 = spi_master_get_devdata(spi->master); | |
1772 | unsigned long flags; | |
1773 | ||
1774 | spin_lock_irqsave(&pl022->queue_lock, flags); | |
1775 | ||
1776 | if (!pl022->running) { | |
1777 | spin_unlock_irqrestore(&pl022->queue_lock, flags); | |
1778 | return -ESHUTDOWN; | |
1779 | } | |
1780 | msg->actual_length = 0; | |
1781 | msg->status = -EINPROGRESS; | |
1782 | msg->state = STATE_START; | |
1783 | ||
1784 | list_add_tail(&msg->queue, &pl022->queue); | |
1785 | if (pl022->running && !pl022->busy) | |
1786 | queue_work(pl022->workqueue, &pl022->pump_messages); | |
1787 | ||
1788 | spin_unlock_irqrestore(&pl022->queue_lock, flags); | |
1789 | return 0; | |
1790 | } | |
1791 | ||
1792 | static inline u32 spi_rate(u32 rate, u16 cpsdvsr, u16 scr) | |
1793 | { | |
1794 | return rate / (cpsdvsr * (1 + scr)); | |
1795 | } | |
1796 | ||
1797 | static int calculate_effective_freq(struct pl022 *pl022, int freq, struct | |
1798 | ssp_clock_params * clk_freq) | |
1799 | { | |
1800 | /* Lets calculate the frequency parameters */ | |
1801 | u16 cpsdvsr = CPSDVR_MIN, scr = SCR_MIN; | |
1802 | u32 rate, max_tclk, min_tclk, best_freq = 0, best_cpsdvsr = 0, | |
1803 | best_scr = 0, tmp, found = 0; | |
1804 | ||
1805 | rate = clk_get_rate(pl022->clk); | |
1806 | /* cpsdvscr = 2 & scr 0 */ | |
1807 | max_tclk = spi_rate(rate, CPSDVR_MIN, SCR_MIN); | |
1808 | /* cpsdvsr = 254 & scr = 255 */ | |
1809 | min_tclk = spi_rate(rate, CPSDVR_MAX, SCR_MAX); | |
1810 | ||
1811 | if (!((freq <= max_tclk) && (freq >= min_tclk))) { | |
1812 | dev_err(&pl022->adev->dev, | |
1813 | "controller data is incorrect: out of range frequency"); | |
1814 | return -EINVAL; | |
1815 | } | |
1816 | ||
1817 | /* | |
1818 | * best_freq will give closest possible available rate (<= requested | |
1819 | * freq) for all values of scr & cpsdvsr. | |
1820 | */ | |
1821 | while ((cpsdvsr <= CPSDVR_MAX) && !found) { | |
1822 | while (scr <= SCR_MAX) { | |
1823 | tmp = spi_rate(rate, cpsdvsr, scr); | |
1824 | ||
1825 | if (tmp > freq) | |
1826 | scr++; | |
1827 | /* | |
1828 | * If found exact value, update and break. | |
1829 | * If found more closer value, update and continue. | |
1830 | */ | |
1831 | else if ((tmp == freq) || (tmp > best_freq)) { | |
1832 | best_freq = tmp; | |
1833 | best_cpsdvsr = cpsdvsr; | |
1834 | best_scr = scr; | |
1835 | ||
1836 | if (tmp == freq) | |
1837 | break; | |
1838 | } | |
1839 | scr++; | |
1840 | } | |
1841 | cpsdvsr += 2; | |
1842 | scr = SCR_MIN; | |
1843 | } | |
1844 | ||
1845 | clk_freq->cpsdvsr = (u8) (best_cpsdvsr & 0xFF); | |
1846 | clk_freq->scr = (u8) (best_scr & 0xFF); | |
1847 | dev_dbg(&pl022->adev->dev, | |
1848 | "SSP Target Frequency is: %u, Effective Frequency is %u\n", | |
1849 | freq, best_freq); | |
1850 | dev_dbg(&pl022->adev->dev, "SSP cpsdvsr = %d, scr = %d\n", | |
1851 | clk_freq->cpsdvsr, clk_freq->scr); | |
1852 | ||
1853 | return 0; | |
1854 | } | |
1855 | ||
1856 | /* | |
1857 | * A piece of default chip info unless the platform | |
1858 | * supplies it. | |
1859 | */ | |
1860 | static const struct pl022_config_chip pl022_default_chip_info = { | |
1861 | .com_mode = POLLING_TRANSFER, | |
1862 | .iface = SSP_INTERFACE_MOTOROLA_SPI, | |
1863 | .hierarchy = SSP_SLAVE, | |
1864 | .slave_tx_disable = DO_NOT_DRIVE_TX, | |
1865 | .rx_lev_trig = SSP_RX_1_OR_MORE_ELEM, | |
1866 | .tx_lev_trig = SSP_TX_1_OR_MORE_EMPTY_LOC, | |
1867 | .ctrl_len = SSP_BITS_8, | |
1868 | .wait_state = SSP_MWIRE_WAIT_ZERO, | |
1869 | .duplex = SSP_MICROWIRE_CHANNEL_FULL_DUPLEX, | |
1870 | .cs_control = null_cs_control, | |
1871 | }; | |
1872 | ||
1873 | /** | |
1874 | * pl022_setup - setup function registered to SPI master framework | |
1875 | * @spi: spi device which is requesting setup | |
1876 | * | |
1877 | * This function is registered to the SPI framework for this SPI master | |
1878 | * controller. If it is the first time when setup is called by this device, | |
1879 | * this function will initialize the runtime state for this chip and save | |
1880 | * the same in the device structure. Else it will update the runtime info | |
1881 | * with the updated chip info. Nothing is really being written to the | |
1882 | * controller hardware here, that is not done until the actual transfer | |
1883 | * commence. | |
1884 | */ | |
1885 | static int pl022_setup(struct spi_device *spi) | |
1886 | { | |
1887 | struct pl022_config_chip const *chip_info; | |
1888 | struct chip_data *chip; | |
1889 | struct ssp_clock_params clk_freq = {0, }; | |
1890 | int status = 0; | |
1891 | struct pl022 *pl022 = spi_master_get_devdata(spi->master); | |
1892 | unsigned int bits = spi->bits_per_word; | |
1893 | u32 tmp; | |
1894 | ||
1895 | if (!spi->max_speed_hz) | |
1896 | return -EINVAL; | |
1897 | ||
1898 | /* Get controller_state if one is supplied */ | |
1899 | chip = spi_get_ctldata(spi); | |
1900 | ||
1901 | if (chip == NULL) { | |
1902 | chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL); | |
1903 | if (!chip) { | |
1904 | dev_err(&spi->dev, | |
1905 | "cannot allocate controller state\n"); | |
1906 | return -ENOMEM; | |
1907 | } | |
1908 | dev_dbg(&spi->dev, | |
1909 | "allocated memory for controller's runtime state\n"); | |
1910 | } | |
1911 | ||
1912 | /* Get controller data if one is supplied */ | |
1913 | chip_info = spi->controller_data; | |
1914 | ||
1915 | if (chip_info == NULL) { | |
1916 | chip_info = &pl022_default_chip_info; | |
1917 | /* spi_board_info.controller_data not is supplied */ | |
1918 | dev_dbg(&spi->dev, | |
1919 | "using default controller_data settings\n"); | |
1920 | } else | |
1921 | dev_dbg(&spi->dev, | |
1922 | "using user supplied controller_data settings\n"); | |
1923 | ||
1924 | /* | |
1925 | * We can override with custom divisors, else we use the board | |
1926 | * frequency setting | |
1927 | */ | |
1928 | if ((0 == chip_info->clk_freq.cpsdvsr) | |
1929 | && (0 == chip_info->clk_freq.scr)) { | |
1930 | status = calculate_effective_freq(pl022, | |
1931 | spi->max_speed_hz, | |
1932 | &clk_freq); | |
1933 | if (status < 0) | |
1934 | goto err_config_params; | |
1935 | } else { | |
1936 | memcpy(&clk_freq, &chip_info->clk_freq, sizeof(clk_freq)); | |
1937 | if ((clk_freq.cpsdvsr % 2) != 0) | |
1938 | clk_freq.cpsdvsr = | |
1939 | clk_freq.cpsdvsr - 1; | |
1940 | } | |
1941 | if ((clk_freq.cpsdvsr < CPSDVR_MIN) | |
1942 | || (clk_freq.cpsdvsr > CPSDVR_MAX)) { | |
1943 | status = -EINVAL; | |
1944 | dev_err(&spi->dev, | |
1945 | "cpsdvsr is configured incorrectly\n"); | |
1946 | goto err_config_params; | |
1947 | } | |
1948 | ||
1949 | status = verify_controller_parameters(pl022, chip_info); | |
1950 | if (status) { | |
1951 | dev_err(&spi->dev, "controller data is incorrect"); | |
1952 | goto err_config_params; | |
1953 | } | |
1954 | ||
1955 | pl022->rx_lev_trig = chip_info->rx_lev_trig; | |
1956 | pl022->tx_lev_trig = chip_info->tx_lev_trig; | |
1957 | ||
1958 | /* Now set controller state based on controller data */ | |
1959 | chip->xfer_type = chip_info->com_mode; | |
1960 | if (!chip_info->cs_control) { | |
1961 | chip->cs_control = null_cs_control; | |
1962 | dev_warn(&spi->dev, | |
1963 | "chip select function is NULL for this chip\n"); | |
1964 | } else | |
1965 | chip->cs_control = chip_info->cs_control; | |
1966 | ||
1967 | if (bits <= 3) { | |
1968 | /* PL022 doesn't support less than 4-bits */ | |
1969 | status = -ENOTSUPP; | |
1970 | goto err_config_params; | |
1971 | } else if (bits <= 8) { | |
1972 | dev_dbg(&spi->dev, "4 <= n <=8 bits per word\n"); | |
1973 | chip->n_bytes = 1; | |
1974 | chip->read = READING_U8; | |
1975 | chip->write = WRITING_U8; | |
1976 | } else if (bits <= 16) { | |
1977 | dev_dbg(&spi->dev, "9 <= n <= 16 bits per word\n"); | |
1978 | chip->n_bytes = 2; | |
1979 | chip->read = READING_U16; | |
1980 | chip->write = WRITING_U16; | |
1981 | } else { | |
1982 | if (pl022->vendor->max_bpw >= 32) { | |
1983 | dev_dbg(&spi->dev, "17 <= n <= 32 bits per word\n"); | |
1984 | chip->n_bytes = 4; | |
1985 | chip->read = READING_U32; | |
1986 | chip->write = WRITING_U32; | |
1987 | } else { | |
1988 | dev_err(&spi->dev, | |
1989 | "illegal data size for this controller!\n"); | |
1990 | dev_err(&spi->dev, | |
1991 | "a standard pl022 can only handle " | |
1992 | "1 <= n <= 16 bit words\n"); | |
1993 | status = -ENOTSUPP; | |
1994 | goto err_config_params; | |
1995 | } | |
1996 | } | |
1997 | ||
1998 | /* Now Initialize all register settings required for this chip */ | |
1999 | chip->cr0 = 0; | |
2000 | chip->cr1 = 0; | |
2001 | chip->dmacr = 0; | |
2002 | chip->cpsr = 0; | |
2003 | if ((chip_info->com_mode == DMA_TRANSFER) | |
2004 | && ((pl022->master_info)->enable_dma)) { | |
2005 | chip->enable_dma = true; | |
2006 | dev_dbg(&spi->dev, "DMA mode set in controller state\n"); | |
2007 | SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED, | |
2008 | SSP_DMACR_MASK_RXDMAE, 0); | |
2009 | SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED, | |
2010 | SSP_DMACR_MASK_TXDMAE, 1); | |
2011 | } else { | |
2012 | chip->enable_dma = false; | |
2013 | dev_dbg(&spi->dev, "DMA mode NOT set in controller state\n"); | |
2014 | SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED, | |
2015 | SSP_DMACR_MASK_RXDMAE, 0); | |
2016 | SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED, | |
2017 | SSP_DMACR_MASK_TXDMAE, 1); | |
2018 | } | |
2019 | ||
2020 | chip->cpsr = clk_freq.cpsdvsr; | |
2021 | ||
2022 | /* Special setup for the ST micro extended control registers */ | |
2023 | if (pl022->vendor->extended_cr) { | |
2024 | u32 etx; | |
2025 | ||
2026 | if (pl022->vendor->pl023) { | |
2027 | /* These bits are only in the PL023 */ | |
2028 | SSP_WRITE_BITS(chip->cr1, chip_info->clkdelay, | |
2029 | SSP_CR1_MASK_FBCLKDEL_ST, 13); | |
2030 | } else { | |
2031 | /* These bits are in the PL022 but not PL023 */ | |
2032 | SSP_WRITE_BITS(chip->cr0, chip_info->duplex, | |
2033 | SSP_CR0_MASK_HALFDUP_ST, 5); | |
2034 | SSP_WRITE_BITS(chip->cr0, chip_info->ctrl_len, | |
2035 | SSP_CR0_MASK_CSS_ST, 16); | |
2036 | SSP_WRITE_BITS(chip->cr0, chip_info->iface, | |
2037 | SSP_CR0_MASK_FRF_ST, 21); | |
2038 | SSP_WRITE_BITS(chip->cr1, chip_info->wait_state, | |
2039 | SSP_CR1_MASK_MWAIT_ST, 6); | |
2040 | } | |
2041 | SSP_WRITE_BITS(chip->cr0, bits - 1, | |
2042 | SSP_CR0_MASK_DSS_ST, 0); | |
2043 | ||
2044 | if (spi->mode & SPI_LSB_FIRST) { | |
2045 | tmp = SSP_RX_LSB; | |
2046 | etx = SSP_TX_LSB; | |
2047 | } else { | |
2048 | tmp = SSP_RX_MSB; | |
2049 | etx = SSP_TX_MSB; | |
2050 | } | |
2051 | SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_RENDN_ST, 4); | |
2052 | SSP_WRITE_BITS(chip->cr1, etx, SSP_CR1_MASK_TENDN_ST, 5); | |
2053 | SSP_WRITE_BITS(chip->cr1, chip_info->rx_lev_trig, | |
2054 | SSP_CR1_MASK_RXIFLSEL_ST, 7); | |
2055 | SSP_WRITE_BITS(chip->cr1, chip_info->tx_lev_trig, | |
2056 | SSP_CR1_MASK_TXIFLSEL_ST, 10); | |
2057 | } else { | |
2058 | SSP_WRITE_BITS(chip->cr0, bits - 1, | |
2059 | SSP_CR0_MASK_DSS, 0); | |
2060 | SSP_WRITE_BITS(chip->cr0, chip_info->iface, | |
2061 | SSP_CR0_MASK_FRF, 4); | |
2062 | } | |
2063 | ||
2064 | /* Stuff that is common for all versions */ | |
2065 | if (spi->mode & SPI_CPOL) | |
2066 | tmp = SSP_CLK_POL_IDLE_HIGH; | |
2067 | else | |
2068 | tmp = SSP_CLK_POL_IDLE_LOW; | |
2069 | SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPO, 6); | |
2070 | ||
2071 | if (spi->mode & SPI_CPHA) | |
2072 | tmp = SSP_CLK_SECOND_EDGE; | |
2073 | else | |
2074 | tmp = SSP_CLK_FIRST_EDGE; | |
2075 | SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPH, 7); | |
2076 | ||
2077 | SSP_WRITE_BITS(chip->cr0, clk_freq.scr, SSP_CR0_MASK_SCR, 8); | |
2078 | /* Loopback is available on all versions except PL023 */ | |
2079 | if (pl022->vendor->loopback) { | |
2080 | if (spi->mode & SPI_LOOP) | |
2081 | tmp = LOOPBACK_ENABLED; | |
2082 | else | |
2083 | tmp = LOOPBACK_DISABLED; | |
2084 | SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_LBM, 0); | |
2085 | } | |
2086 | SSP_WRITE_BITS(chip->cr1, SSP_DISABLED, SSP_CR1_MASK_SSE, 1); | |
2087 | SSP_WRITE_BITS(chip->cr1, chip_info->hierarchy, SSP_CR1_MASK_MS, 2); | |
2088 | SSP_WRITE_BITS(chip->cr1, chip_info->slave_tx_disable, SSP_CR1_MASK_SOD, | |
2089 | 3); | |
2090 | ||
2091 | /* Save controller_state */ | |
2092 | spi_set_ctldata(spi, chip); | |
2093 | return status; | |
2094 | err_config_params: | |
2095 | spi_set_ctldata(spi, NULL); | |
2096 | kfree(chip); | |
2097 | return status; | |
2098 | } | |
2099 | ||
2100 | /** | |
2101 | * pl022_cleanup - cleanup function registered to SPI master framework | |
2102 | * @spi: spi device which is requesting cleanup | |
2103 | * | |
2104 | * This function is registered to the SPI framework for this SPI master | |
2105 | * controller. It will free the runtime state of chip. | |
2106 | */ | |
2107 | static void pl022_cleanup(struct spi_device *spi) | |
2108 | { | |
2109 | struct chip_data *chip = spi_get_ctldata(spi); | |
2110 | ||
2111 | spi_set_ctldata(spi, NULL); | |
2112 | kfree(chip); | |
2113 | } | |
2114 | ||
2115 | static int __devinit | |
2116 | pl022_probe(struct amba_device *adev, const struct amba_id *id) | |
2117 | { | |
2118 | struct device *dev = &adev->dev; | |
2119 | struct pl022_ssp_controller *platform_info = adev->dev.platform_data; | |
2120 | struct spi_master *master; | |
2121 | struct pl022 *pl022 = NULL; /*Data for this driver */ | |
2122 | int status = 0; | |
2123 | ||
2124 | dev_info(&adev->dev, | |
2125 | "ARM PL022 driver, device ID: 0x%08x\n", adev->periphid); | |
2126 | if (platform_info == NULL) { | |
2127 | dev_err(&adev->dev, "probe - no platform data supplied\n"); | |
2128 | status = -ENODEV; | |
2129 | goto err_no_pdata; | |
2130 | } | |
2131 | ||
2132 | /* Allocate master with space for data */ | |
2133 | master = spi_alloc_master(dev, sizeof(struct pl022)); | |
2134 | if (master == NULL) { | |
2135 | dev_err(&adev->dev, "probe - cannot alloc SPI master\n"); | |
2136 | status = -ENOMEM; | |
2137 | goto err_no_master; | |
2138 | } | |
2139 | ||
2140 | pl022 = spi_master_get_devdata(master); | |
2141 | pl022->master = master; | |
2142 | pl022->master_info = platform_info; | |
2143 | pl022->adev = adev; | |
2144 | pl022->vendor = id->data; | |
2145 | ||
2146 | /* | |
2147 | * Bus Number Which has been Assigned to this SSP controller | |
2148 | * on this board | |
2149 | */ | |
2150 | master->bus_num = platform_info->bus_id; | |
2151 | master->num_chipselect = platform_info->num_chipselect; | |
2152 | master->cleanup = pl022_cleanup; | |
2153 | master->setup = pl022_setup; | |
2154 | master->transfer = pl022_transfer; | |
2155 | ||
2156 | /* | |
2157 | * Supports mode 0-3, loopback, and active low CS. Transfers are | |
2158 | * always MS bit first on the original pl022. | |
2159 | */ | |
2160 | master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP; | |
2161 | if (pl022->vendor->extended_cr) | |
2162 | master->mode_bits |= SPI_LSB_FIRST; | |
2163 | ||
2164 | dev_dbg(&adev->dev, "BUSNO: %d\n", master->bus_num); | |
2165 | ||
2166 | status = amba_request_regions(adev, NULL); | |
2167 | if (status) | |
2168 | goto err_no_ioregion; | |
2169 | ||
2170 | pl022->phybase = adev->res.start; | |
2171 | pl022->virtbase = ioremap(adev->res.start, resource_size(&adev->res)); | |
2172 | if (pl022->virtbase == NULL) { | |
2173 | status = -ENOMEM; | |
2174 | goto err_no_ioremap; | |
2175 | } | |
2176 | printk(KERN_INFO "pl022: mapped registers from 0x%08x to %p\n", | |
2177 | adev->res.start, pl022->virtbase); | |
2178 | ||
2179 | pl022->clk = clk_get(&adev->dev, NULL); | |
2180 | if (IS_ERR(pl022->clk)) { | |
2181 | status = PTR_ERR(pl022->clk); | |
2182 | dev_err(&adev->dev, "could not retrieve SSP/SPI bus clock\n"); | |
2183 | goto err_no_clk; | |
2184 | } | |
2185 | ||
2186 | status = clk_prepare(pl022->clk); | |
2187 | if (status) { | |
2188 | dev_err(&adev->dev, "could not prepare SSP/SPI bus clock\n"); | |
2189 | goto err_clk_prep; | |
2190 | } | |
2191 | ||
2192 | status = clk_enable(pl022->clk); | |
2193 | if (status) { | |
2194 | dev_err(&adev->dev, "could not enable SSP/SPI bus clock\n"); | |
2195 | goto err_no_clk_en; | |
2196 | } | |
2197 | ||
2198 | /* Disable SSP */ | |
2199 | writew((readw(SSP_CR1(pl022->virtbase)) & (~SSP_CR1_MASK_SSE)), | |
2200 | SSP_CR1(pl022->virtbase)); | |
2201 | load_ssp_default_config(pl022); | |
2202 | ||
2203 | status = request_irq(adev->irq[0], pl022_interrupt_handler, 0, "pl022", | |
2204 | pl022); | |
2205 | if (status < 0) { | |
2206 | dev_err(&adev->dev, "probe - cannot get IRQ (%d)\n", status); | |
2207 | goto err_no_irq; | |
2208 | } | |
2209 | ||
2210 | /* Get DMA channels */ | |
2211 | if (platform_info->enable_dma) { | |
2212 | status = pl022_dma_probe(pl022); | |
2213 | if (status != 0) | |
2214 | platform_info->enable_dma = 0; | |
2215 | } | |
2216 | ||
2217 | /* Initialize and start queue */ | |
2218 | status = init_queue(pl022); | |
2219 | if (status != 0) { | |
2220 | dev_err(&adev->dev, "probe - problem initializing queue\n"); | |
2221 | goto err_init_queue; | |
2222 | } | |
2223 | status = start_queue(pl022); | |
2224 | if (status != 0) { | |
2225 | dev_err(&adev->dev, "probe - problem starting queue\n"); | |
2226 | goto err_start_queue; | |
2227 | } | |
2228 | /* Register with the SPI framework */ | |
2229 | amba_set_drvdata(adev, pl022); | |
2230 | status = spi_register_master(master); | |
2231 | if (status != 0) { | |
2232 | dev_err(&adev->dev, | |
2233 | "probe - problem registering spi master\n"); | |
2234 | goto err_spi_register; | |
2235 | } | |
2236 | dev_dbg(dev, "probe succeeded\n"); | |
2237 | ||
2238 | /* let runtime pm put suspend */ | |
2239 | pm_runtime_put(dev); | |
2240 | return 0; | |
2241 | ||
2242 | err_spi_register: | |
2243 | err_start_queue: | |
2244 | err_init_queue: | |
2245 | destroy_queue(pl022); | |
2246 | if (platform_info->enable_dma) | |
2247 | pl022_dma_remove(pl022); | |
2248 | ||
2249 | free_irq(adev->irq[0], pl022); | |
2250 | err_no_irq: | |
2251 | clk_disable(pl022->clk); | |
2252 | err_no_clk_en: | |
2253 | clk_unprepare(pl022->clk); | |
2254 | err_clk_prep: | |
2255 | clk_put(pl022->clk); | |
2256 | err_no_clk: | |
2257 | iounmap(pl022->virtbase); | |
2258 | err_no_ioremap: | |
2259 | amba_release_regions(adev); | |
2260 | err_no_ioregion: | |
2261 | spi_master_put(master); | |
2262 | err_no_master: | |
2263 | err_no_pdata: | |
2264 | return status; | |
2265 | } | |
2266 | ||
2267 | static int __devexit | |
2268 | pl022_remove(struct amba_device *adev) | |
2269 | { | |
2270 | struct pl022 *pl022 = amba_get_drvdata(adev); | |
2271 | ||
2272 | if (!pl022) | |
2273 | return 0; | |
2274 | ||
2275 | /* | |
2276 | * undo pm_runtime_put() in probe. I assume that we're not | |
2277 | * accessing the primecell here. | |
2278 | */ | |
2279 | pm_runtime_get_noresume(&adev->dev); | |
2280 | ||
2281 | /* Remove the queue */ | |
2282 | if (destroy_queue(pl022) != 0) | |
2283 | dev_err(&adev->dev, "queue remove failed\n"); | |
2284 | load_ssp_default_config(pl022); | |
2285 | if (pl022->master_info->enable_dma) | |
2286 | pl022_dma_remove(pl022); | |
2287 | ||
2288 | free_irq(adev->irq[0], pl022); | |
2289 | clk_disable(pl022->clk); | |
2290 | clk_unprepare(pl022->clk); | |
2291 | clk_put(pl022->clk); | |
2292 | iounmap(pl022->virtbase); | |
2293 | amba_release_regions(adev); | |
2294 | tasklet_disable(&pl022->pump_transfers); | |
2295 | spi_unregister_master(pl022->master); | |
2296 | spi_master_put(pl022->master); | |
2297 | amba_set_drvdata(adev, NULL); | |
2298 | return 0; | |
2299 | } | |
2300 | ||
2301 | #ifdef CONFIG_SUSPEND | |
2302 | static int pl022_suspend(struct device *dev) | |
2303 | { | |
2304 | struct pl022 *pl022 = dev_get_drvdata(dev); | |
2305 | int status = 0; | |
2306 | ||
2307 | status = stop_queue(pl022); | |
2308 | if (status) { | |
2309 | dev_warn(dev, "suspend cannot stop queue\n"); | |
2310 | return status; | |
2311 | } | |
2312 | ||
2313 | amba_vcore_enable(pl022->adev); | |
2314 | amba_pclk_enable(pl022->adev); | |
2315 | load_ssp_default_config(pl022); | |
2316 | amba_pclk_disable(pl022->adev); | |
2317 | amba_vcore_disable(pl022->adev); | |
2318 | dev_dbg(dev, "suspended\n"); | |
2319 | return 0; | |
2320 | } | |
2321 | ||
2322 | static int pl022_resume(struct device *dev) | |
2323 | { | |
2324 | struct pl022 *pl022 = dev_get_drvdata(dev); | |
2325 | int status = 0; | |
2326 | ||
2327 | /* Start the queue running */ | |
2328 | status = start_queue(pl022); | |
2329 | if (status) | |
2330 | dev_err(dev, "problem starting queue (%d)\n", status); | |
2331 | else | |
2332 | dev_dbg(dev, "resumed\n"); | |
2333 | ||
2334 | return status; | |
2335 | } | |
2336 | #endif /* CONFIG_PM */ | |
2337 | ||
2338 | #ifdef CONFIG_PM_RUNTIME | |
2339 | static int pl022_runtime_suspend(struct device *dev) | |
2340 | { | |
2341 | struct pl022 *pl022 = dev_get_drvdata(dev); | |
2342 | ||
2343 | clk_disable(pl022->clk); | |
2344 | amba_vcore_disable(pl022->adev); | |
2345 | ||
2346 | return 0; | |
2347 | } | |
2348 | ||
2349 | static int pl022_runtime_resume(struct device *dev) | |
2350 | { | |
2351 | struct pl022 *pl022 = dev_get_drvdata(dev); | |
2352 | ||
2353 | amba_vcore_enable(pl022->adev); | |
2354 | clk_enable(pl022->clk); | |
2355 | ||
2356 | return 0; | |
2357 | } | |
2358 | #endif | |
2359 | ||
2360 | static const struct dev_pm_ops pl022_dev_pm_ops = { | |
2361 | SET_SYSTEM_SLEEP_PM_OPS(pl022_suspend, pl022_resume) | |
2362 | SET_RUNTIME_PM_OPS(pl022_runtime_suspend, pl022_runtime_resume, NULL) | |
2363 | }; | |
2364 | ||
2365 | static struct vendor_data vendor_arm = { | |
2366 | .fifodepth = 8, | |
2367 | .max_bpw = 16, | |
2368 | .unidir = false, | |
2369 | .extended_cr = false, | |
2370 | .pl023 = false, | |
2371 | .loopback = true, | |
2372 | }; | |
2373 | ||
2374 | static struct vendor_data vendor_st = { | |
2375 | .fifodepth = 32, | |
2376 | .max_bpw = 32, | |
2377 | .unidir = false, | |
2378 | .extended_cr = true, | |
2379 | .pl023 = false, | |
2380 | .loopback = true, | |
2381 | }; | |
2382 | ||
2383 | static struct vendor_data vendor_st_pl023 = { | |
2384 | .fifodepth = 32, | |
2385 | .max_bpw = 32, | |
2386 | .unidir = false, | |
2387 | .extended_cr = true, | |
2388 | .pl023 = true, | |
2389 | .loopback = false, | |
2390 | }; | |
2391 | ||
2392 | static struct vendor_data vendor_db5500_pl023 = { | |
2393 | .fifodepth = 32, | |
2394 | .max_bpw = 32, | |
2395 | .unidir = false, | |
2396 | .extended_cr = true, | |
2397 | .pl023 = true, | |
2398 | .loopback = true, | |
2399 | }; | |
2400 | ||
2401 | static struct amba_id pl022_ids[] = { | |
2402 | { | |
2403 | /* | |
2404 | * ARM PL022 variant, this has a 16bit wide | |
2405 | * and 8 locations deep TX/RX FIFO | |
2406 | */ | |
2407 | .id = 0x00041022, | |
2408 | .mask = 0x000fffff, | |
2409 | .data = &vendor_arm, | |
2410 | }, | |
2411 | { | |
2412 | /* | |
2413 | * ST Micro derivative, this has 32bit wide | |
2414 | * and 32 locations deep TX/RX FIFO | |
2415 | */ | |
2416 | .id = 0x01080022, | |
2417 | .mask = 0xffffffff, | |
2418 | .data = &vendor_st, | |
2419 | }, | |
2420 | { | |
2421 | /* | |
2422 | * ST-Ericsson derivative "PL023" (this is not | |
2423 | * an official ARM number), this is a PL022 SSP block | |
2424 | * stripped to SPI mode only, it has 32bit wide | |
2425 | * and 32 locations deep TX/RX FIFO but no extended | |
2426 | * CR0/CR1 register | |
2427 | */ | |
2428 | .id = 0x00080023, | |
2429 | .mask = 0xffffffff, | |
2430 | .data = &vendor_st_pl023, | |
2431 | }, | |
2432 | { | |
2433 | .id = 0x10080023, | |
2434 | .mask = 0xffffffff, | |
2435 | .data = &vendor_db5500_pl023, | |
2436 | }, | |
2437 | { 0, 0 }, | |
2438 | }; | |
2439 | ||
2440 | static struct amba_driver pl022_driver = { | |
2441 | .drv = { | |
2442 | .name = "ssp-pl022", | |
2443 | .pm = &pl022_dev_pm_ops, | |
2444 | }, | |
2445 | .id_table = pl022_ids, | |
2446 | .probe = pl022_probe, | |
2447 | .remove = __devexit_p(pl022_remove), | |
2448 | }; | |
2449 | ||
2450 | static int __init pl022_init(void) | |
2451 | { | |
2452 | return amba_driver_register(&pl022_driver); | |
2453 | } | |
2454 | subsys_initcall(pl022_init); | |
2455 | ||
2456 | static void __exit pl022_exit(void) | |
2457 | { | |
2458 | amba_driver_unregister(&pl022_driver); | |
2459 | } | |
2460 | module_exit(pl022_exit); | |
2461 | ||
2462 | MODULE_AUTHOR("Linus Walleij <linus.walleij@stericsson.com>"); | |
2463 | MODULE_DESCRIPTION("PL022 SSP Controller Driver"); | |
2464 | MODULE_LICENSE("GPL"); |