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754ce4f2 HS |
1 | /* |
2 | * Driver for Atmel AT32 and AT91 SPI Controllers | |
3 | * | |
4 | * Copyright (C) 2006 Atmel Corporation | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the GNU General Public License version 2 as | |
8 | * published by the Free Software Foundation. | |
9 | */ | |
10 | ||
11 | #include <linux/kernel.h> | |
754ce4f2 HS |
12 | #include <linux/clk.h> |
13 | #include <linux/module.h> | |
14 | #include <linux/platform_device.h> | |
15 | #include <linux/delay.h> | |
16 | #include <linux/dma-mapping.h> | |
1ccc404a | 17 | #include <linux/dmaengine.h> |
754ce4f2 HS |
18 | #include <linux/err.h> |
19 | #include <linux/interrupt.h> | |
20 | #include <linux/spi/spi.h> | |
5a0e3ad6 | 21 | #include <linux/slab.h> |
1ccc404a | 22 | #include <linux/platform_data/dma-atmel.h> |
850a5b67 | 23 | #include <linux/of.h> |
754ce4f2 | 24 | |
d4820b74 WY |
25 | #include <linux/io.h> |
26 | #include <linux/gpio.h> | |
96106200 | 27 | #include <linux/of_gpio.h> |
5bdfd491 | 28 | #include <linux/pinctrl/consumer.h> |
ce0c4caf | 29 | #include <linux/pm_runtime.h> |
bb2d1c36 | 30 | |
ca632f55 GL |
31 | /* SPI register offsets */ |
32 | #define SPI_CR 0x0000 | |
33 | #define SPI_MR 0x0004 | |
34 | #define SPI_RDR 0x0008 | |
35 | #define SPI_TDR 0x000c | |
36 | #define SPI_SR 0x0010 | |
37 | #define SPI_IER 0x0014 | |
38 | #define SPI_IDR 0x0018 | |
39 | #define SPI_IMR 0x001c | |
40 | #define SPI_CSR0 0x0030 | |
41 | #define SPI_CSR1 0x0034 | |
42 | #define SPI_CSR2 0x0038 | |
43 | #define SPI_CSR3 0x003c | |
11f2764f CP |
44 | #define SPI_FMR 0x0040 |
45 | #define SPI_FLR 0x0044 | |
d4820b74 | 46 | #define SPI_VERSION 0x00fc |
ca632f55 GL |
47 | #define SPI_RPR 0x0100 |
48 | #define SPI_RCR 0x0104 | |
49 | #define SPI_TPR 0x0108 | |
50 | #define SPI_TCR 0x010c | |
51 | #define SPI_RNPR 0x0110 | |
52 | #define SPI_RNCR 0x0114 | |
53 | #define SPI_TNPR 0x0118 | |
54 | #define SPI_TNCR 0x011c | |
55 | #define SPI_PTCR 0x0120 | |
56 | #define SPI_PTSR 0x0124 | |
57 | ||
58 | /* Bitfields in CR */ | |
59 | #define SPI_SPIEN_OFFSET 0 | |
60 | #define SPI_SPIEN_SIZE 1 | |
61 | #define SPI_SPIDIS_OFFSET 1 | |
62 | #define SPI_SPIDIS_SIZE 1 | |
63 | #define SPI_SWRST_OFFSET 7 | |
64 | #define SPI_SWRST_SIZE 1 | |
65 | #define SPI_LASTXFER_OFFSET 24 | |
66 | #define SPI_LASTXFER_SIZE 1 | |
11f2764f CP |
67 | #define SPI_TXFCLR_OFFSET 16 |
68 | #define SPI_TXFCLR_SIZE 1 | |
69 | #define SPI_RXFCLR_OFFSET 17 | |
70 | #define SPI_RXFCLR_SIZE 1 | |
71 | #define SPI_FIFOEN_OFFSET 30 | |
72 | #define SPI_FIFOEN_SIZE 1 | |
73 | #define SPI_FIFODIS_OFFSET 31 | |
74 | #define SPI_FIFODIS_SIZE 1 | |
ca632f55 GL |
75 | |
76 | /* Bitfields in MR */ | |
77 | #define SPI_MSTR_OFFSET 0 | |
78 | #define SPI_MSTR_SIZE 1 | |
79 | #define SPI_PS_OFFSET 1 | |
80 | #define SPI_PS_SIZE 1 | |
81 | #define SPI_PCSDEC_OFFSET 2 | |
82 | #define SPI_PCSDEC_SIZE 1 | |
83 | #define SPI_FDIV_OFFSET 3 | |
84 | #define SPI_FDIV_SIZE 1 | |
85 | #define SPI_MODFDIS_OFFSET 4 | |
86 | #define SPI_MODFDIS_SIZE 1 | |
d4820b74 WY |
87 | #define SPI_WDRBT_OFFSET 5 |
88 | #define SPI_WDRBT_SIZE 1 | |
ca632f55 GL |
89 | #define SPI_LLB_OFFSET 7 |
90 | #define SPI_LLB_SIZE 1 | |
91 | #define SPI_PCS_OFFSET 16 | |
92 | #define SPI_PCS_SIZE 4 | |
93 | #define SPI_DLYBCS_OFFSET 24 | |
94 | #define SPI_DLYBCS_SIZE 8 | |
95 | ||
96 | /* Bitfields in RDR */ | |
97 | #define SPI_RD_OFFSET 0 | |
98 | #define SPI_RD_SIZE 16 | |
99 | ||
100 | /* Bitfields in TDR */ | |
101 | #define SPI_TD_OFFSET 0 | |
102 | #define SPI_TD_SIZE 16 | |
103 | ||
104 | /* Bitfields in SR */ | |
105 | #define SPI_RDRF_OFFSET 0 | |
106 | #define SPI_RDRF_SIZE 1 | |
107 | #define SPI_TDRE_OFFSET 1 | |
108 | #define SPI_TDRE_SIZE 1 | |
109 | #define SPI_MODF_OFFSET 2 | |
110 | #define SPI_MODF_SIZE 1 | |
111 | #define SPI_OVRES_OFFSET 3 | |
112 | #define SPI_OVRES_SIZE 1 | |
113 | #define SPI_ENDRX_OFFSET 4 | |
114 | #define SPI_ENDRX_SIZE 1 | |
115 | #define SPI_ENDTX_OFFSET 5 | |
116 | #define SPI_ENDTX_SIZE 1 | |
117 | #define SPI_RXBUFF_OFFSET 6 | |
118 | #define SPI_RXBUFF_SIZE 1 | |
119 | #define SPI_TXBUFE_OFFSET 7 | |
120 | #define SPI_TXBUFE_SIZE 1 | |
121 | #define SPI_NSSR_OFFSET 8 | |
122 | #define SPI_NSSR_SIZE 1 | |
123 | #define SPI_TXEMPTY_OFFSET 9 | |
124 | #define SPI_TXEMPTY_SIZE 1 | |
125 | #define SPI_SPIENS_OFFSET 16 | |
126 | #define SPI_SPIENS_SIZE 1 | |
11f2764f CP |
127 | #define SPI_TXFEF_OFFSET 24 |
128 | #define SPI_TXFEF_SIZE 1 | |
129 | #define SPI_TXFFF_OFFSET 25 | |
130 | #define SPI_TXFFF_SIZE 1 | |
131 | #define SPI_TXFTHF_OFFSET 26 | |
132 | #define SPI_TXFTHF_SIZE 1 | |
133 | #define SPI_RXFEF_OFFSET 27 | |
134 | #define SPI_RXFEF_SIZE 1 | |
135 | #define SPI_RXFFF_OFFSET 28 | |
136 | #define SPI_RXFFF_SIZE 1 | |
137 | #define SPI_RXFTHF_OFFSET 29 | |
138 | #define SPI_RXFTHF_SIZE 1 | |
139 | #define SPI_TXFPTEF_OFFSET 30 | |
140 | #define SPI_TXFPTEF_SIZE 1 | |
141 | #define SPI_RXFPTEF_OFFSET 31 | |
142 | #define SPI_RXFPTEF_SIZE 1 | |
ca632f55 GL |
143 | |
144 | /* Bitfields in CSR0 */ | |
145 | #define SPI_CPOL_OFFSET 0 | |
146 | #define SPI_CPOL_SIZE 1 | |
147 | #define SPI_NCPHA_OFFSET 1 | |
148 | #define SPI_NCPHA_SIZE 1 | |
149 | #define SPI_CSAAT_OFFSET 3 | |
150 | #define SPI_CSAAT_SIZE 1 | |
151 | #define SPI_BITS_OFFSET 4 | |
152 | #define SPI_BITS_SIZE 4 | |
153 | #define SPI_SCBR_OFFSET 8 | |
154 | #define SPI_SCBR_SIZE 8 | |
155 | #define SPI_DLYBS_OFFSET 16 | |
156 | #define SPI_DLYBS_SIZE 8 | |
157 | #define SPI_DLYBCT_OFFSET 24 | |
158 | #define SPI_DLYBCT_SIZE 8 | |
159 | ||
160 | /* Bitfields in RCR */ | |
161 | #define SPI_RXCTR_OFFSET 0 | |
162 | #define SPI_RXCTR_SIZE 16 | |
163 | ||
164 | /* Bitfields in TCR */ | |
165 | #define SPI_TXCTR_OFFSET 0 | |
166 | #define SPI_TXCTR_SIZE 16 | |
167 | ||
168 | /* Bitfields in RNCR */ | |
169 | #define SPI_RXNCR_OFFSET 0 | |
170 | #define SPI_RXNCR_SIZE 16 | |
171 | ||
172 | /* Bitfields in TNCR */ | |
173 | #define SPI_TXNCR_OFFSET 0 | |
174 | #define SPI_TXNCR_SIZE 16 | |
175 | ||
176 | /* Bitfields in PTCR */ | |
177 | #define SPI_RXTEN_OFFSET 0 | |
178 | #define SPI_RXTEN_SIZE 1 | |
179 | #define SPI_RXTDIS_OFFSET 1 | |
180 | #define SPI_RXTDIS_SIZE 1 | |
181 | #define SPI_TXTEN_OFFSET 8 | |
182 | #define SPI_TXTEN_SIZE 1 | |
183 | #define SPI_TXTDIS_OFFSET 9 | |
184 | #define SPI_TXTDIS_SIZE 1 | |
185 | ||
11f2764f CP |
186 | /* Bitfields in FMR */ |
187 | #define SPI_TXRDYM_OFFSET 0 | |
188 | #define SPI_TXRDYM_SIZE 2 | |
189 | #define SPI_RXRDYM_OFFSET 4 | |
190 | #define SPI_RXRDYM_SIZE 2 | |
191 | #define SPI_TXFTHRES_OFFSET 16 | |
192 | #define SPI_TXFTHRES_SIZE 6 | |
193 | #define SPI_RXFTHRES_OFFSET 24 | |
194 | #define SPI_RXFTHRES_SIZE 6 | |
195 | ||
196 | /* Bitfields in FLR */ | |
197 | #define SPI_TXFL_OFFSET 0 | |
198 | #define SPI_TXFL_SIZE 6 | |
199 | #define SPI_RXFL_OFFSET 16 | |
200 | #define SPI_RXFL_SIZE 6 | |
201 | ||
ca632f55 GL |
202 | /* Constants for BITS */ |
203 | #define SPI_BITS_8_BPT 0 | |
204 | #define SPI_BITS_9_BPT 1 | |
205 | #define SPI_BITS_10_BPT 2 | |
206 | #define SPI_BITS_11_BPT 3 | |
207 | #define SPI_BITS_12_BPT 4 | |
208 | #define SPI_BITS_13_BPT 5 | |
209 | #define SPI_BITS_14_BPT 6 | |
210 | #define SPI_BITS_15_BPT 7 | |
211 | #define SPI_BITS_16_BPT 8 | |
11f2764f CP |
212 | #define SPI_ONE_DATA 0 |
213 | #define SPI_TWO_DATA 1 | |
214 | #define SPI_FOUR_DATA 2 | |
ca632f55 GL |
215 | |
216 | /* Bit manipulation macros */ | |
217 | #define SPI_BIT(name) \ | |
218 | (1 << SPI_##name##_OFFSET) | |
a536d765 | 219 | #define SPI_BF(name, value) \ |
ca632f55 | 220 | (((value) & ((1 << SPI_##name##_SIZE) - 1)) << SPI_##name##_OFFSET) |
a536d765 | 221 | #define SPI_BFEXT(name, value) \ |
ca632f55 | 222 | (((value) >> SPI_##name##_OFFSET) & ((1 << SPI_##name##_SIZE) - 1)) |
a536d765 SK |
223 | #define SPI_BFINS(name, value, old) \ |
224 | (((old) & ~(((1 << SPI_##name##_SIZE) - 1) << SPI_##name##_OFFSET)) \ | |
225 | | SPI_BF(name, value)) | |
ca632f55 GL |
226 | |
227 | /* Register access macros */ | |
ea467326 | 228 | #ifdef CONFIG_AVR32 |
a536d765 | 229 | #define spi_readl(port, reg) \ |
ca632f55 | 230 | __raw_readl((port)->regs + SPI_##reg) |
a536d765 | 231 | #define spi_writel(port, reg, value) \ |
ca632f55 | 232 | __raw_writel((value), (port)->regs + SPI_##reg) |
11f2764f CP |
233 | |
234 | #define spi_readw(port, reg) \ | |
235 | __raw_readw((port)->regs + SPI_##reg) | |
236 | #define spi_writew(port, reg, value) \ | |
237 | __raw_writew((value), (port)->regs + SPI_##reg) | |
238 | ||
239 | #define spi_readb(port, reg) \ | |
240 | __raw_readb((port)->regs + SPI_##reg) | |
241 | #define spi_writeb(port, reg, value) \ | |
242 | __raw_writeb((value), (port)->regs + SPI_##reg) | |
ea467326 BD |
243 | #else |
244 | #define spi_readl(port, reg) \ | |
245 | readl_relaxed((port)->regs + SPI_##reg) | |
246 | #define spi_writel(port, reg, value) \ | |
247 | writel_relaxed((value), (port)->regs + SPI_##reg) | |
11f2764f CP |
248 | |
249 | #define spi_readw(port, reg) \ | |
250 | readw_relaxed((port)->regs + SPI_##reg) | |
251 | #define spi_writew(port, reg, value) \ | |
252 | writew_relaxed((value), (port)->regs + SPI_##reg) | |
253 | ||
254 | #define spi_readb(port, reg) \ | |
255 | readb_relaxed((port)->regs + SPI_##reg) | |
256 | #define spi_writeb(port, reg, value) \ | |
257 | writeb_relaxed((value), (port)->regs + SPI_##reg) | |
ea467326 | 258 | #endif |
1ccc404a NF |
259 | /* use PIO for small transfers, avoiding DMA setup/teardown overhead and |
260 | * cache operations; better heuristics consider wordsize and bitrate. | |
261 | */ | |
262 | #define DMA_MIN_BYTES 16 | |
263 | ||
8090d6d1 WY |
264 | #define SPI_DMA_TIMEOUT (msecs_to_jiffies(1000)) |
265 | ||
ce0c4caf WY |
266 | #define AUTOSUSPEND_TIMEOUT 2000 |
267 | ||
d4820b74 WY |
268 | struct atmel_spi_caps { |
269 | bool is_spi2; | |
270 | bool has_wdrbt; | |
271 | bool has_dma_support; | |
7094576c | 272 | bool has_pdc_support; |
d4820b74 | 273 | }; |
754ce4f2 HS |
274 | |
275 | /* | |
276 | * The core SPI transfer engine just talks to a register bank to set up | |
277 | * DMA transfers; transfer queue progress is driven by IRQs. The clock | |
278 | * framework provides the base clock, subdivided for each spi_device. | |
754ce4f2 HS |
279 | */ |
280 | struct atmel_spi { | |
281 | spinlock_t lock; | |
8aad7924 | 282 | unsigned long flags; |
754ce4f2 | 283 | |
dfab30ee | 284 | phys_addr_t phybase; |
754ce4f2 HS |
285 | void __iomem *regs; |
286 | int irq; | |
287 | struct clk *clk; | |
288 | struct platform_device *pdev; | |
39fe33f9 | 289 | unsigned long spi_clk; |
754ce4f2 | 290 | |
754ce4f2 | 291 | struct spi_transfer *current_transfer; |
0c3b9748 | 292 | int current_remaining_bytes; |
823cd045 | 293 | int done_status; |
754ce4f2 | 294 | |
8090d6d1 WY |
295 | struct completion xfer_completion; |
296 | ||
d4820b74 | 297 | struct atmel_spi_caps caps; |
1ccc404a NF |
298 | |
299 | bool use_dma; | |
300 | bool use_pdc; | |
48203034 | 301 | bool use_cs_gpios; |
8090d6d1 WY |
302 | |
303 | bool keep_cs; | |
304 | bool cs_active; | |
11f2764f CP |
305 | |
306 | u32 fifo_size; | |
754ce4f2 HS |
307 | }; |
308 | ||
5ee36c98 HS |
309 | /* Controller-specific per-slave state */ |
310 | struct atmel_spi_device { | |
311 | unsigned int npcs_pin; | |
312 | u32 csr; | |
313 | }; | |
314 | ||
7910d9af | 315 | #define SPI_MAX_DMA_XFER 65535 /* true for both PDC and DMA */ |
754ce4f2 HS |
316 | #define INVALID_DMA_ADDRESS 0xffffffff |
317 | ||
5bfa26ca HS |
318 | /* |
319 | * Version 2 of the SPI controller has | |
320 | * - CR.LASTXFER | |
321 | * - SPI_MR.DIV32 may become FDIV or must-be-zero (here: always zero) | |
322 | * - SPI_SR.TXEMPTY, SPI_SR.NSSR (and corresponding irqs) | |
323 | * - SPI_CSRx.CSAAT | |
324 | * - SPI_CSRx.SBCR allows faster clocking | |
5bfa26ca | 325 | */ |
d4820b74 | 326 | static bool atmel_spi_is_v2(struct atmel_spi *as) |
5bfa26ca | 327 | { |
d4820b74 | 328 | return as->caps.is_spi2; |
5bfa26ca HS |
329 | } |
330 | ||
754ce4f2 HS |
331 | /* |
332 | * Earlier SPI controllers (e.g. on at91rm9200) have a design bug whereby | |
333 | * they assume that spi slave device state will not change on deselect, so | |
defbd3b4 DB |
334 | * that automagic deselection is OK. ("NPCSx rises if no data is to be |
335 | * transmitted") Not so! Workaround uses nCSx pins as GPIOs; or newer | |
336 | * controllers have CSAAT and friends. | |
754ce4f2 | 337 | * |
defbd3b4 DB |
338 | * Since the CSAAT functionality is a bit weird on newer controllers as |
339 | * well, we use GPIO to control nCSx pins on all controllers, updating | |
340 | * MR.PCS to avoid confusing the controller. Using GPIOs also lets us | |
341 | * support active-high chipselects despite the controller's belief that | |
342 | * only active-low devices/systems exists. | |
343 | * | |
344 | * However, at91rm9200 has a second erratum whereby nCS0 doesn't work | |
345 | * right when driven with GPIO. ("Mode Fault does not allow more than one | |
346 | * Master on Chip Select 0.") No workaround exists for that ... so for | |
347 | * nCS0 on that chip, we (a) don't use the GPIO, (b) can't support CS_HIGH, | |
348 | * and (c) will trigger that first erratum in some cases. | |
754ce4f2 HS |
349 | */ |
350 | ||
defbd3b4 | 351 | static void cs_activate(struct atmel_spi *as, struct spi_device *spi) |
754ce4f2 | 352 | { |
5ee36c98 | 353 | struct atmel_spi_device *asd = spi->controller_state; |
754ce4f2 | 354 | unsigned active = spi->mode & SPI_CS_HIGH; |
defbd3b4 DB |
355 | u32 mr; |
356 | ||
d4820b74 | 357 | if (atmel_spi_is_v2(as)) { |
97ed465b WY |
358 | spi_writel(as, CSR0 + 4 * spi->chip_select, asd->csr); |
359 | /* For the low SPI version, there is a issue that PDC transfer | |
360 | * on CS1,2,3 needs SPI_CSR0.BITS config as SPI_CSR1,2,3.BITS | |
5ee36c98 HS |
361 | */ |
362 | spi_writel(as, CSR0, asd->csr); | |
d4820b74 | 363 | if (as->caps.has_wdrbt) { |
97ed465b WY |
364 | spi_writel(as, MR, |
365 | SPI_BF(PCS, ~(0x01 << spi->chip_select)) | |
366 | | SPI_BIT(WDRBT) | |
367 | | SPI_BIT(MODFDIS) | |
368 | | SPI_BIT(MSTR)); | |
d4820b74 | 369 | } else { |
97ed465b WY |
370 | spi_writel(as, MR, |
371 | SPI_BF(PCS, ~(0x01 << spi->chip_select)) | |
372 | | SPI_BIT(MODFDIS) | |
373 | | SPI_BIT(MSTR)); | |
d4820b74 | 374 | } |
1ccc404a | 375 | |
5ee36c98 | 376 | mr = spi_readl(as, MR); |
48203034 CP |
377 | if (as->use_cs_gpios) |
378 | gpio_set_value(asd->npcs_pin, active); | |
5ee36c98 HS |
379 | } else { |
380 | u32 cpol = (spi->mode & SPI_CPOL) ? SPI_BIT(CPOL) : 0; | |
381 | int i; | |
382 | u32 csr; | |
383 | ||
384 | /* Make sure clock polarity is correct */ | |
385 | for (i = 0; i < spi->master->num_chipselect; i++) { | |
386 | csr = spi_readl(as, CSR0 + 4 * i); | |
387 | if ((csr ^ cpol) & SPI_BIT(CPOL)) | |
388 | spi_writel(as, CSR0 + 4 * i, | |
389 | csr ^ SPI_BIT(CPOL)); | |
390 | } | |
391 | ||
392 | mr = spi_readl(as, MR); | |
393 | mr = SPI_BFINS(PCS, ~(1 << spi->chip_select), mr); | |
48203034 | 394 | if (as->use_cs_gpios && spi->chip_select != 0) |
5ee36c98 HS |
395 | gpio_set_value(asd->npcs_pin, active); |
396 | spi_writel(as, MR, mr); | |
397 | } | |
defbd3b4 DB |
398 | |
399 | dev_dbg(&spi->dev, "activate %u%s, mr %08x\n", | |
5ee36c98 | 400 | asd->npcs_pin, active ? " (high)" : "", |
defbd3b4 | 401 | mr); |
754ce4f2 HS |
402 | } |
403 | ||
defbd3b4 | 404 | static void cs_deactivate(struct atmel_spi *as, struct spi_device *spi) |
754ce4f2 | 405 | { |
5ee36c98 | 406 | struct atmel_spi_device *asd = spi->controller_state; |
754ce4f2 | 407 | unsigned active = spi->mode & SPI_CS_HIGH; |
defbd3b4 DB |
408 | u32 mr; |
409 | ||
410 | /* only deactivate *this* device; sometimes transfers to | |
411 | * another device may be active when this routine is called. | |
412 | */ | |
413 | mr = spi_readl(as, MR); | |
414 | if (~SPI_BFEXT(PCS, mr) & (1 << spi->chip_select)) { | |
415 | mr = SPI_BFINS(PCS, 0xf, mr); | |
416 | spi_writel(as, MR, mr); | |
417 | } | |
754ce4f2 | 418 | |
defbd3b4 | 419 | dev_dbg(&spi->dev, "DEactivate %u%s, mr %08x\n", |
5ee36c98 | 420 | asd->npcs_pin, active ? " (low)" : "", |
defbd3b4 DB |
421 | mr); |
422 | ||
48203034 CP |
423 | if (!as->use_cs_gpios) |
424 | spi_writel(as, CR, SPI_BIT(LASTXFER)); | |
425 | else if (atmel_spi_is_v2(as) || spi->chip_select != 0) | |
5ee36c98 | 426 | gpio_set_value(asd->npcs_pin, !active); |
754ce4f2 HS |
427 | } |
428 | ||
6c07ef29 | 429 | static void atmel_spi_lock(struct atmel_spi *as) __acquires(&as->lock) |
8aad7924 NF |
430 | { |
431 | spin_lock_irqsave(&as->lock, as->flags); | |
432 | } | |
433 | ||
6c07ef29 | 434 | static void atmel_spi_unlock(struct atmel_spi *as) __releases(&as->lock) |
8aad7924 NF |
435 | { |
436 | spin_unlock_irqrestore(&as->lock, as->flags); | |
437 | } | |
438 | ||
1ccc404a NF |
439 | static inline bool atmel_spi_use_dma(struct atmel_spi *as, |
440 | struct spi_transfer *xfer) | |
441 | { | |
442 | return as->use_dma && xfer->len >= DMA_MIN_BYTES; | |
443 | } | |
444 | ||
04242ca4 CP |
445 | static bool atmel_spi_can_dma(struct spi_master *master, |
446 | struct spi_device *spi, | |
447 | struct spi_transfer *xfer) | |
448 | { | |
449 | struct atmel_spi *as = spi_master_get_devdata(master); | |
450 | ||
451 | return atmel_spi_use_dma(as, xfer); | |
452 | } | |
453 | ||
1ccc404a NF |
454 | static int atmel_spi_dma_slave_config(struct atmel_spi *as, |
455 | struct dma_slave_config *slave_config, | |
456 | u8 bits_per_word) | |
457 | { | |
768f3d9d | 458 | struct spi_master *master = platform_get_drvdata(as->pdev); |
1ccc404a NF |
459 | int err = 0; |
460 | ||
461 | if (bits_per_word > 8) { | |
462 | slave_config->dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES; | |
463 | slave_config->src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES; | |
464 | } else { | |
465 | slave_config->dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; | |
466 | slave_config->src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; | |
467 | } | |
468 | ||
469 | slave_config->dst_addr = (dma_addr_t)as->phybase + SPI_TDR; | |
470 | slave_config->src_addr = (dma_addr_t)as->phybase + SPI_RDR; | |
471 | slave_config->src_maxburst = 1; | |
472 | slave_config->dst_maxburst = 1; | |
473 | slave_config->device_fc = false; | |
474 | ||
11f2764f CP |
475 | /* |
476 | * This driver uses fixed peripheral select mode (PS bit set to '0' in | |
477 | * the Mode Register). | |
478 | * So according to the datasheet, when FIFOs are available (and | |
479 | * enabled), the Transmit FIFO operates in Multiple Data Mode. | |
480 | * In this mode, up to 2 data, not 4, can be written into the Transmit | |
481 | * Data Register in a single access. | |
482 | * However, the first data has to be written into the lowest 16 bits and | |
483 | * the second data into the highest 16 bits of the Transmit | |
484 | * Data Register. For 8bit data (the most frequent case), it would | |
485 | * require to rework tx_buf so each data would actualy fit 16 bits. | |
486 | * So we'd rather write only one data at the time. Hence the transmit | |
487 | * path works the same whether FIFOs are available (and enabled) or not. | |
488 | */ | |
1ccc404a | 489 | slave_config->direction = DMA_MEM_TO_DEV; |
768f3d9d | 490 | if (dmaengine_slave_config(master->dma_tx, slave_config)) { |
1ccc404a NF |
491 | dev_err(&as->pdev->dev, |
492 | "failed to configure tx dma channel\n"); | |
493 | err = -EINVAL; | |
494 | } | |
495 | ||
11f2764f CP |
496 | /* |
497 | * This driver configures the spi controller for master mode (MSTR bit | |
498 | * set to '1' in the Mode Register). | |
499 | * So according to the datasheet, when FIFOs are available (and | |
500 | * enabled), the Receive FIFO operates in Single Data Mode. | |
501 | * So the receive path works the same whether FIFOs are available (and | |
502 | * enabled) or not. | |
503 | */ | |
1ccc404a | 504 | slave_config->direction = DMA_DEV_TO_MEM; |
768f3d9d | 505 | if (dmaengine_slave_config(master->dma_rx, slave_config)) { |
1ccc404a NF |
506 | dev_err(&as->pdev->dev, |
507 | "failed to configure rx dma channel\n"); | |
508 | err = -EINVAL; | |
509 | } | |
510 | ||
511 | return err; | |
512 | } | |
513 | ||
768f3d9d NF |
514 | static int atmel_spi_configure_dma(struct spi_master *master, |
515 | struct atmel_spi *as) | |
1ccc404a | 516 | { |
1ccc404a | 517 | struct dma_slave_config slave_config; |
2f767a9f | 518 | struct device *dev = &as->pdev->dev; |
1ccc404a NF |
519 | int err; |
520 | ||
2f767a9f RG |
521 | dma_cap_mask_t mask; |
522 | dma_cap_zero(mask); | |
523 | dma_cap_set(DMA_SLAVE, mask); | |
1ccc404a | 524 | |
768f3d9d NF |
525 | master->dma_tx = dma_request_slave_channel_reason(dev, "tx"); |
526 | if (IS_ERR(master->dma_tx)) { | |
527 | err = PTR_ERR(master->dma_tx); | |
5e9af37e LD |
528 | if (err == -EPROBE_DEFER) { |
529 | dev_warn(dev, "no DMA channel available at the moment\n"); | |
768f3d9d | 530 | goto error_clear; |
5e9af37e | 531 | } |
2f767a9f RG |
532 | dev_err(dev, |
533 | "DMA TX channel not available, SPI unable to use DMA\n"); | |
534 | err = -EBUSY; | |
768f3d9d | 535 | goto error_clear; |
1ccc404a | 536 | } |
2f767a9f | 537 | |
5e9af37e LD |
538 | /* |
539 | * No reason to check EPROBE_DEFER here since we have already requested | |
540 | * tx channel. If it fails here, it's for another reason. | |
541 | */ | |
768f3d9d | 542 | master->dma_rx = dma_request_slave_channel(dev, "rx"); |
2f767a9f | 543 | |
768f3d9d | 544 | if (!master->dma_rx) { |
2f767a9f RG |
545 | dev_err(dev, |
546 | "DMA RX channel not available, SPI unable to use DMA\n"); | |
1ccc404a NF |
547 | err = -EBUSY; |
548 | goto error; | |
549 | } | |
550 | ||
551 | err = atmel_spi_dma_slave_config(as, &slave_config, 8); | |
552 | if (err) | |
553 | goto error; | |
554 | ||
555 | dev_info(&as->pdev->dev, | |
556 | "Using %s (tx) and %s (rx) for DMA transfers\n", | |
768f3d9d NF |
557 | dma_chan_name(master->dma_tx), |
558 | dma_chan_name(master->dma_rx)); | |
559 | ||
1ccc404a NF |
560 | return 0; |
561 | error: | |
768f3d9d NF |
562 | if (master->dma_rx) |
563 | dma_release_channel(master->dma_rx); | |
564 | if (!IS_ERR(master->dma_tx)) | |
565 | dma_release_channel(master->dma_tx); | |
566 | error_clear: | |
567 | master->dma_tx = master->dma_rx = NULL; | |
1ccc404a NF |
568 | return err; |
569 | } | |
570 | ||
768f3d9d | 571 | static void atmel_spi_stop_dma(struct spi_master *master) |
1ccc404a | 572 | { |
768f3d9d NF |
573 | if (master->dma_rx) |
574 | dmaengine_terminate_all(master->dma_rx); | |
575 | if (master->dma_tx) | |
576 | dmaengine_terminate_all(master->dma_tx); | |
1ccc404a NF |
577 | } |
578 | ||
768f3d9d | 579 | static void atmel_spi_release_dma(struct spi_master *master) |
1ccc404a | 580 | { |
768f3d9d NF |
581 | if (master->dma_rx) { |
582 | dma_release_channel(master->dma_rx); | |
583 | master->dma_rx = NULL; | |
584 | } | |
585 | if (master->dma_tx) { | |
586 | dma_release_channel(master->dma_tx); | |
587 | master->dma_tx = NULL; | |
588 | } | |
1ccc404a NF |
589 | } |
590 | ||
591 | /* This function is called by the DMA driver from tasklet context */ | |
592 | static void dma_callback(void *data) | |
593 | { | |
594 | struct spi_master *master = data; | |
595 | struct atmel_spi *as = spi_master_get_devdata(master); | |
596 | ||
8090d6d1 | 597 | complete(&as->xfer_completion); |
1ccc404a NF |
598 | } |
599 | ||
600 | /* | |
11f2764f | 601 | * Next transfer using PIO without FIFO. |
1ccc404a | 602 | */ |
11f2764f CP |
603 | static void atmel_spi_next_xfer_single(struct spi_master *master, |
604 | struct spi_transfer *xfer) | |
1ccc404a NF |
605 | { |
606 | struct atmel_spi *as = spi_master_get_devdata(master); | |
8090d6d1 | 607 | unsigned long xfer_pos = xfer->len - as->current_remaining_bytes; |
1ccc404a NF |
608 | |
609 | dev_vdbg(master->dev.parent, "atmel_spi_next_xfer_pio\n"); | |
610 | ||
1ccc404a NF |
611 | /* Make sure data is not remaining in RDR */ |
612 | spi_readl(as, RDR); | |
613 | while (spi_readl(as, SR) & SPI_BIT(RDRF)) { | |
614 | spi_readl(as, RDR); | |
615 | cpu_relax(); | |
616 | } | |
617 | ||
7910d9af NF |
618 | if (xfer->bits_per_word > 8) |
619 | spi_writel(as, TDR, *(u16 *)(xfer->tx_buf + xfer_pos)); | |
620 | else | |
621 | spi_writel(as, TDR, *(u8 *)(xfer->tx_buf + xfer_pos)); | |
1ccc404a NF |
622 | |
623 | dev_dbg(master->dev.parent, | |
f557c98b RG |
624 | " start pio xfer %p: len %u tx %p rx %p bitpw %d\n", |
625 | xfer, xfer->len, xfer->tx_buf, xfer->rx_buf, | |
626 | xfer->bits_per_word); | |
1ccc404a NF |
627 | |
628 | /* Enable relevant interrupts */ | |
629 | spi_writel(as, IER, SPI_BIT(RDRF) | SPI_BIT(OVRES)); | |
630 | } | |
631 | ||
11f2764f CP |
632 | /* |
633 | * Next transfer using PIO with FIFO. | |
634 | */ | |
635 | static void atmel_spi_next_xfer_fifo(struct spi_master *master, | |
636 | struct spi_transfer *xfer) | |
637 | { | |
638 | struct atmel_spi *as = spi_master_get_devdata(master); | |
639 | u32 current_remaining_data, num_data; | |
640 | u32 offset = xfer->len - as->current_remaining_bytes; | |
641 | const u16 *words = (const u16 *)((u8 *)xfer->tx_buf + offset); | |
642 | const u8 *bytes = (const u8 *)((u8 *)xfer->tx_buf + offset); | |
643 | u16 td0, td1; | |
644 | u32 fifomr; | |
645 | ||
646 | dev_vdbg(master->dev.parent, "atmel_spi_next_xfer_fifo\n"); | |
647 | ||
648 | /* Compute the number of data to transfer in the current iteration */ | |
649 | current_remaining_data = ((xfer->bits_per_word > 8) ? | |
650 | ((u32)as->current_remaining_bytes >> 1) : | |
651 | (u32)as->current_remaining_bytes); | |
652 | num_data = min(current_remaining_data, as->fifo_size); | |
653 | ||
654 | /* Flush RX and TX FIFOs */ | |
655 | spi_writel(as, CR, SPI_BIT(RXFCLR) | SPI_BIT(TXFCLR)); | |
656 | while (spi_readl(as, FLR)) | |
657 | cpu_relax(); | |
658 | ||
659 | /* Set RX FIFO Threshold to the number of data to transfer */ | |
660 | fifomr = spi_readl(as, FMR); | |
661 | spi_writel(as, FMR, SPI_BFINS(RXFTHRES, num_data, fifomr)); | |
662 | ||
663 | /* Clear FIFO flags in the Status Register, especially RXFTHF */ | |
664 | (void)spi_readl(as, SR); | |
665 | ||
666 | /* Fill TX FIFO */ | |
667 | while (num_data >= 2) { | |
7910d9af NF |
668 | if (xfer->bits_per_word > 8) { |
669 | td0 = *words++; | |
670 | td1 = *words++; | |
11f2764f | 671 | } else { |
7910d9af NF |
672 | td0 = *bytes++; |
673 | td1 = *bytes++; | |
11f2764f CP |
674 | } |
675 | ||
676 | spi_writel(as, TDR, (td1 << 16) | td0); | |
677 | num_data -= 2; | |
678 | } | |
679 | ||
680 | if (num_data) { | |
7910d9af NF |
681 | if (xfer->bits_per_word > 8) |
682 | td0 = *words++; | |
683 | else | |
684 | td0 = *bytes++; | |
11f2764f CP |
685 | |
686 | spi_writew(as, TDR, td0); | |
687 | num_data--; | |
688 | } | |
689 | ||
690 | dev_dbg(master->dev.parent, | |
691 | " start fifo xfer %p: len %u tx %p rx %p bitpw %d\n", | |
692 | xfer, xfer->len, xfer->tx_buf, xfer->rx_buf, | |
693 | xfer->bits_per_word); | |
694 | ||
695 | /* | |
696 | * Enable RX FIFO Threshold Flag interrupt to be notified about | |
697 | * transfer completion. | |
698 | */ | |
699 | spi_writel(as, IER, SPI_BIT(RXFTHF) | SPI_BIT(OVRES)); | |
700 | } | |
701 | ||
702 | /* | |
703 | * Next transfer using PIO. | |
704 | */ | |
705 | static void atmel_spi_next_xfer_pio(struct spi_master *master, | |
706 | struct spi_transfer *xfer) | |
707 | { | |
708 | struct atmel_spi *as = spi_master_get_devdata(master); | |
709 | ||
710 | if (as->fifo_size) | |
711 | atmel_spi_next_xfer_fifo(master, xfer); | |
712 | else | |
713 | atmel_spi_next_xfer_single(master, xfer); | |
714 | } | |
715 | ||
1ccc404a NF |
716 | /* |
717 | * Submit next transfer for DMA. | |
1ccc404a NF |
718 | */ |
719 | static int atmel_spi_next_xfer_dma_submit(struct spi_master *master, | |
720 | struct spi_transfer *xfer, | |
721 | u32 *plen) | |
722 | { | |
723 | struct atmel_spi *as = spi_master_get_devdata(master); | |
768f3d9d NF |
724 | struct dma_chan *rxchan = master->dma_rx; |
725 | struct dma_chan *txchan = master->dma_tx; | |
1ccc404a NF |
726 | struct dma_async_tx_descriptor *rxdesc; |
727 | struct dma_async_tx_descriptor *txdesc; | |
728 | struct dma_slave_config slave_config; | |
729 | dma_cookie_t cookie; | |
1ccc404a NF |
730 | |
731 | dev_vdbg(master->dev.parent, "atmel_spi_next_xfer_dma_submit\n"); | |
732 | ||
733 | /* Check that the channels are available */ | |
734 | if (!rxchan || !txchan) | |
735 | return -ENODEV; | |
736 | ||
737 | /* release lock for DMA operations */ | |
738 | atmel_spi_unlock(as); | |
739 | ||
04242ca4 | 740 | *plen = xfer->len; |
1ccc404a | 741 | |
06515f83 DMT |
742 | if (atmel_spi_dma_slave_config(as, &slave_config, |
743 | xfer->bits_per_word)) | |
1ccc404a NF |
744 | goto err_exit; |
745 | ||
746 | /* Send both scatterlists */ | |
04242ca4 CP |
747 | rxdesc = dmaengine_prep_slave_sg(rxchan, |
748 | xfer->rx_sg.sgl, xfer->rx_sg.nents, | |
ef40eb39 GU |
749 | DMA_FROM_DEVICE, |
750 | DMA_PREP_INTERRUPT | DMA_CTRL_ACK); | |
1ccc404a NF |
751 | if (!rxdesc) |
752 | goto err_dma; | |
753 | ||
04242ca4 CP |
754 | txdesc = dmaengine_prep_slave_sg(txchan, |
755 | xfer->tx_sg.sgl, xfer->tx_sg.nents, | |
ef40eb39 GU |
756 | DMA_TO_DEVICE, |
757 | DMA_PREP_INTERRUPT | DMA_CTRL_ACK); | |
1ccc404a NF |
758 | if (!txdesc) |
759 | goto err_dma; | |
760 | ||
761 | dev_dbg(master->dev.parent, | |
2de024b7 EG |
762 | " start dma xfer %p: len %u tx %p/%08llx rx %p/%08llx\n", |
763 | xfer, xfer->len, xfer->tx_buf, (unsigned long long)xfer->tx_dma, | |
764 | xfer->rx_buf, (unsigned long long)xfer->rx_dma); | |
1ccc404a NF |
765 | |
766 | /* Enable relevant interrupts */ | |
767 | spi_writel(as, IER, SPI_BIT(OVRES)); | |
768 | ||
769 | /* Put the callback on the RX transfer only, that should finish last */ | |
770 | rxdesc->callback = dma_callback; | |
771 | rxdesc->callback_param = master; | |
772 | ||
773 | /* Submit and fire RX and TX with TX last so we're ready to read! */ | |
774 | cookie = rxdesc->tx_submit(rxdesc); | |
775 | if (dma_submit_error(cookie)) | |
776 | goto err_dma; | |
777 | cookie = txdesc->tx_submit(txdesc); | |
778 | if (dma_submit_error(cookie)) | |
779 | goto err_dma; | |
780 | rxchan->device->device_issue_pending(rxchan); | |
781 | txchan->device->device_issue_pending(txchan); | |
782 | ||
783 | /* take back lock */ | |
784 | atmel_spi_lock(as); | |
785 | return 0; | |
786 | ||
787 | err_dma: | |
788 | spi_writel(as, IDR, SPI_BIT(OVRES)); | |
768f3d9d | 789 | atmel_spi_stop_dma(master); |
1ccc404a NF |
790 | err_exit: |
791 | atmel_spi_lock(as); | |
792 | return -ENOMEM; | |
793 | } | |
794 | ||
154443c7 SE |
795 | static void atmel_spi_next_xfer_data(struct spi_master *master, |
796 | struct spi_transfer *xfer, | |
797 | dma_addr_t *tx_dma, | |
798 | dma_addr_t *rx_dma, | |
799 | u32 *plen) | |
800 | { | |
7910d9af NF |
801 | *rx_dma = xfer->rx_dma + xfer->len - *plen; |
802 | *tx_dma = xfer->tx_dma + xfer->len - *plen; | |
04242ca4 CP |
803 | if (*plen > master->max_dma_len) |
804 | *plen = master->max_dma_len; | |
154443c7 SE |
805 | } |
806 | ||
d3b72c7e RG |
807 | static int atmel_spi_set_xfer_speed(struct atmel_spi *as, |
808 | struct spi_device *spi, | |
809 | struct spi_transfer *xfer) | |
810 | { | |
811 | u32 scbr, csr; | |
812 | unsigned long bus_hz; | |
813 | ||
814 | /* v1 chips start out at half the peripheral bus speed. */ | |
39fe33f9 | 815 | bus_hz = as->spi_clk; |
d3b72c7e RG |
816 | if (!atmel_spi_is_v2(as)) |
817 | bus_hz /= 2; | |
818 | ||
819 | /* | |
820 | * Calculate the lowest divider that satisfies the | |
821 | * constraint, assuming div32/fdiv/mbz == 0. | |
822 | */ | |
e8646580 | 823 | scbr = DIV_ROUND_UP(bus_hz, xfer->speed_hz); |
d3b72c7e RG |
824 | |
825 | /* | |
826 | * If the resulting divider doesn't fit into the | |
827 | * register bitfield, we can't satisfy the constraint. | |
828 | */ | |
829 | if (scbr >= (1 << SPI_SCBR_SIZE)) { | |
830 | dev_err(&spi->dev, | |
831 | "setup: %d Hz too slow, scbr %u; min %ld Hz\n", | |
832 | xfer->speed_hz, scbr, bus_hz/255); | |
833 | return -EINVAL; | |
834 | } | |
835 | if (scbr == 0) { | |
836 | dev_err(&spi->dev, | |
837 | "setup: %d Hz too high, scbr %u; max %ld Hz\n", | |
838 | xfer->speed_hz, scbr, bus_hz); | |
839 | return -EINVAL; | |
840 | } | |
841 | csr = spi_readl(as, CSR0 + 4 * spi->chip_select); | |
842 | csr = SPI_BFINS(SCBR, scbr, csr); | |
843 | spi_writel(as, CSR0 + 4 * spi->chip_select, csr); | |
844 | ||
845 | return 0; | |
846 | } | |
847 | ||
754ce4f2 | 848 | /* |
1ccc404a | 849 | * Submit next transfer for PDC. |
754ce4f2 HS |
850 | * lock is held, spi irq is blocked |
851 | */ | |
1ccc404a | 852 | static void atmel_spi_pdc_next_xfer(struct spi_master *master, |
8090d6d1 WY |
853 | struct spi_message *msg, |
854 | struct spi_transfer *xfer) | |
754ce4f2 HS |
855 | { |
856 | struct atmel_spi *as = spi_master_get_devdata(master); | |
8090d6d1 | 857 | u32 len; |
754ce4f2 HS |
858 | dma_addr_t tx_dma, rx_dma; |
859 | ||
8090d6d1 | 860 | spi_writel(as, PTCR, SPI_BIT(RXTDIS) | SPI_BIT(TXTDIS)); |
754ce4f2 | 861 | |
8090d6d1 WY |
862 | len = as->current_remaining_bytes; |
863 | atmel_spi_next_xfer_data(master, xfer, &tx_dma, &rx_dma, &len); | |
864 | as->current_remaining_bytes -= len; | |
754ce4f2 | 865 | |
8090d6d1 WY |
866 | spi_writel(as, RPR, rx_dma); |
867 | spi_writel(as, TPR, tx_dma); | |
754ce4f2 | 868 | |
8090d6d1 WY |
869 | if (msg->spi->bits_per_word > 8) |
870 | len >>= 1; | |
871 | spi_writel(as, RCR, len); | |
872 | spi_writel(as, TCR, len); | |
754ce4f2 | 873 | |
8090d6d1 WY |
874 | dev_dbg(&msg->spi->dev, |
875 | " start xfer %p: len %u tx %p/%08llx rx %p/%08llx\n", | |
876 | xfer, xfer->len, xfer->tx_buf, | |
877 | (unsigned long long)xfer->tx_dma, xfer->rx_buf, | |
878 | (unsigned long long)xfer->rx_dma); | |
dc329442 | 879 | |
8090d6d1 WY |
880 | if (as->current_remaining_bytes) { |
881 | len = as->current_remaining_bytes; | |
154443c7 | 882 | atmel_spi_next_xfer_data(master, xfer, &tx_dma, &rx_dma, &len); |
8090d6d1 | 883 | as->current_remaining_bytes -= len; |
754ce4f2 | 884 | |
154443c7 SE |
885 | spi_writel(as, RNPR, rx_dma); |
886 | spi_writel(as, TNPR, tx_dma); | |
754ce4f2 | 887 | |
154443c7 SE |
888 | if (msg->spi->bits_per_word > 8) |
889 | len >>= 1; | |
890 | spi_writel(as, RNCR, len); | |
891 | spi_writel(as, TNCR, len); | |
8bacb219 HS |
892 | |
893 | dev_dbg(&msg->spi->dev, | |
2de024b7 EG |
894 | " next xfer %p: len %u tx %p/%08llx rx %p/%08llx\n", |
895 | xfer, xfer->len, xfer->tx_buf, | |
896 | (unsigned long long)xfer->tx_dma, xfer->rx_buf, | |
897 | (unsigned long long)xfer->rx_dma); | |
154443c7 SE |
898 | } |
899 | ||
76e1d14b | 900 | /* REVISIT: We're waiting for RXBUFF before we start the next |
754ce4f2 | 901 | * transfer because we need to handle some difficult timing |
76e1d14b TF |
902 | * issues otherwise. If we wait for TXBUFE in one transfer and |
903 | * then starts waiting for RXBUFF in the next, it's difficult | |
904 | * to tell the difference between the RXBUFF interrupt we're | |
905 | * actually waiting for and the RXBUFF interrupt of the | |
754ce4f2 HS |
906 | * previous transfer. |
907 | * | |
908 | * It should be doable, though. Just not now... | |
909 | */ | |
76e1d14b | 910 | spi_writel(as, IER, SPI_BIT(RXBUFF) | SPI_BIT(OVRES)); |
754ce4f2 HS |
911 | spi_writel(as, PTCR, SPI_BIT(TXTEN) | SPI_BIT(RXTEN)); |
912 | } | |
913 | ||
8da0859a DB |
914 | /* |
915 | * For DMA, tx_buf/tx_dma have the same relationship as rx_buf/rx_dma: | |
916 | * - The buffer is either valid for CPU access, else NULL | |
b595076a | 917 | * - If the buffer is valid, so is its DMA address |
8da0859a | 918 | * |
b595076a | 919 | * This driver manages the dma address unless message->is_dma_mapped. |
8da0859a DB |
920 | */ |
921 | static int | |
754ce4f2 HS |
922 | atmel_spi_dma_map_xfer(struct atmel_spi *as, struct spi_transfer *xfer) |
923 | { | |
8da0859a DB |
924 | struct device *dev = &as->pdev->dev; |
925 | ||
754ce4f2 | 926 | xfer->tx_dma = xfer->rx_dma = INVALID_DMA_ADDRESS; |
8da0859a | 927 | if (xfer->tx_buf) { |
214b574a JCPV |
928 | /* tx_buf is a const void* where we need a void * for the dma |
929 | * mapping */ | |
930 | void *nonconst_tx = (void *)xfer->tx_buf; | |
931 | ||
8da0859a | 932 | xfer->tx_dma = dma_map_single(dev, |
214b574a | 933 | nonconst_tx, xfer->len, |
754ce4f2 | 934 | DMA_TO_DEVICE); |
8d8bb39b | 935 | if (dma_mapping_error(dev, xfer->tx_dma)) |
8da0859a DB |
936 | return -ENOMEM; |
937 | } | |
938 | if (xfer->rx_buf) { | |
939 | xfer->rx_dma = dma_map_single(dev, | |
754ce4f2 HS |
940 | xfer->rx_buf, xfer->len, |
941 | DMA_FROM_DEVICE); | |
8d8bb39b | 942 | if (dma_mapping_error(dev, xfer->rx_dma)) { |
8da0859a DB |
943 | if (xfer->tx_buf) |
944 | dma_unmap_single(dev, | |
945 | xfer->tx_dma, xfer->len, | |
946 | DMA_TO_DEVICE); | |
947 | return -ENOMEM; | |
948 | } | |
949 | } | |
950 | return 0; | |
754ce4f2 HS |
951 | } |
952 | ||
953 | static void atmel_spi_dma_unmap_xfer(struct spi_master *master, | |
954 | struct spi_transfer *xfer) | |
955 | { | |
956 | if (xfer->tx_dma != INVALID_DMA_ADDRESS) | |
49dce689 | 957 | dma_unmap_single(master->dev.parent, xfer->tx_dma, |
754ce4f2 HS |
958 | xfer->len, DMA_TO_DEVICE); |
959 | if (xfer->rx_dma != INVALID_DMA_ADDRESS) | |
49dce689 | 960 | dma_unmap_single(master->dev.parent, xfer->rx_dma, |
754ce4f2 HS |
961 | xfer->len, DMA_FROM_DEVICE); |
962 | } | |
963 | ||
1ccc404a NF |
964 | static void atmel_spi_disable_pdc_transfer(struct atmel_spi *as) |
965 | { | |
966 | spi_writel(as, PTCR, SPI_BIT(RXTDIS) | SPI_BIT(TXTDIS)); | |
967 | } | |
968 | ||
1ccc404a | 969 | static void |
11f2764f | 970 | atmel_spi_pump_single_data(struct atmel_spi *as, struct spi_transfer *xfer) |
1ccc404a | 971 | { |
1ccc404a | 972 | u8 *rxp; |
f557c98b | 973 | u16 *rxp16; |
1ccc404a NF |
974 | unsigned long xfer_pos = xfer->len - as->current_remaining_bytes; |
975 | ||
7910d9af NF |
976 | if (xfer->bits_per_word > 8) { |
977 | rxp16 = (u16 *)(((u8 *)xfer->rx_buf) + xfer_pos); | |
978 | *rxp16 = spi_readl(as, RDR); | |
1ccc404a | 979 | } else { |
7910d9af NF |
980 | rxp = ((u8 *)xfer->rx_buf) + xfer_pos; |
981 | *rxp = spi_readl(as, RDR); | |
1ccc404a | 982 | } |
f557c98b | 983 | if (xfer->bits_per_word > 8) { |
b112f058 AB |
984 | if (as->current_remaining_bytes > 2) |
985 | as->current_remaining_bytes -= 2; | |
986 | else | |
f557c98b RG |
987 | as->current_remaining_bytes = 0; |
988 | } else { | |
989 | as->current_remaining_bytes--; | |
990 | } | |
1ccc404a NF |
991 | } |
992 | ||
11f2764f CP |
993 | static void |
994 | atmel_spi_pump_fifo_data(struct atmel_spi *as, struct spi_transfer *xfer) | |
995 | { | |
996 | u32 fifolr = spi_readl(as, FLR); | |
997 | u32 num_bytes, num_data = SPI_BFEXT(RXFL, fifolr); | |
998 | u32 offset = xfer->len - as->current_remaining_bytes; | |
999 | u16 *words = (u16 *)((u8 *)xfer->rx_buf + offset); | |
1000 | u8 *bytes = (u8 *)((u8 *)xfer->rx_buf + offset); | |
1001 | u16 rd; /* RD field is the lowest 16 bits of RDR */ | |
1002 | ||
1003 | /* Update the number of remaining bytes to transfer */ | |
1004 | num_bytes = ((xfer->bits_per_word > 8) ? | |
1005 | (num_data << 1) : | |
1006 | num_data); | |
1007 | ||
1008 | if (as->current_remaining_bytes > num_bytes) | |
1009 | as->current_remaining_bytes -= num_bytes; | |
1010 | else | |
1011 | as->current_remaining_bytes = 0; | |
1012 | ||
1013 | /* Handle odd number of bytes when data are more than 8bit width */ | |
1014 | if (xfer->bits_per_word > 8) | |
1015 | as->current_remaining_bytes &= ~0x1; | |
1016 | ||
1017 | /* Read data */ | |
1018 | while (num_data) { | |
1019 | rd = spi_readl(as, RDR); | |
7910d9af NF |
1020 | if (xfer->bits_per_word > 8) |
1021 | *words++ = rd; | |
1022 | else | |
1023 | *bytes++ = rd; | |
11f2764f CP |
1024 | num_data--; |
1025 | } | |
1026 | } | |
1027 | ||
1028 | /* Called from IRQ | |
1029 | * | |
1030 | * Must update "current_remaining_bytes" to keep track of data | |
1031 | * to transfer. | |
1032 | */ | |
1033 | static void | |
1034 | atmel_spi_pump_pio_data(struct atmel_spi *as, struct spi_transfer *xfer) | |
1035 | { | |
1036 | if (as->fifo_size) | |
1037 | atmel_spi_pump_fifo_data(as, xfer); | |
1038 | else | |
1039 | atmel_spi_pump_single_data(as, xfer); | |
1040 | } | |
1041 | ||
1ccc404a NF |
1042 | /* Interrupt |
1043 | * | |
1044 | * No need for locking in this Interrupt handler: done_status is the | |
8090d6d1 | 1045 | * only information modified. |
1ccc404a NF |
1046 | */ |
1047 | static irqreturn_t | |
1048 | atmel_spi_pio_interrupt(int irq, void *dev_id) | |
1049 | { | |
1050 | struct spi_master *master = dev_id; | |
1051 | struct atmel_spi *as = spi_master_get_devdata(master); | |
1052 | u32 status, pending, imr; | |
1053 | struct spi_transfer *xfer; | |
1054 | int ret = IRQ_NONE; | |
1055 | ||
1056 | imr = spi_readl(as, IMR); | |
1057 | status = spi_readl(as, SR); | |
1058 | pending = status & imr; | |
1059 | ||
1060 | if (pending & SPI_BIT(OVRES)) { | |
1061 | ret = IRQ_HANDLED; | |
1062 | spi_writel(as, IDR, SPI_BIT(OVRES)); | |
1063 | dev_warn(master->dev.parent, "overrun\n"); | |
1064 | ||
1065 | /* | |
1066 | * When we get an overrun, we disregard the current | |
1067 | * transfer. Data will not be copied back from any | |
1068 | * bounce buffer and msg->actual_len will not be | |
1069 | * updated with the last xfer. | |
1070 | * | |
1071 | * We will also not process any remaning transfers in | |
1072 | * the message. | |
1ccc404a NF |
1073 | */ |
1074 | as->done_status = -EIO; | |
1075 | smp_wmb(); | |
1076 | ||
1077 | /* Clear any overrun happening while cleaning up */ | |
1078 | spi_readl(as, SR); | |
1079 | ||
8090d6d1 | 1080 | complete(&as->xfer_completion); |
1ccc404a | 1081 | |
11f2764f | 1082 | } else if (pending & (SPI_BIT(RDRF) | SPI_BIT(RXFTHF))) { |
1ccc404a NF |
1083 | atmel_spi_lock(as); |
1084 | ||
1085 | if (as->current_remaining_bytes) { | |
1086 | ret = IRQ_HANDLED; | |
1087 | xfer = as->current_transfer; | |
1088 | atmel_spi_pump_pio_data(as, xfer); | |
8090d6d1 | 1089 | if (!as->current_remaining_bytes) |
1ccc404a | 1090 | spi_writel(as, IDR, pending); |
8090d6d1 WY |
1091 | |
1092 | complete(&as->xfer_completion); | |
1ccc404a NF |
1093 | } |
1094 | ||
1095 | atmel_spi_unlock(as); | |
1096 | } else { | |
1097 | WARN_ONCE(pending, "IRQ not handled, pending = %x\n", pending); | |
1098 | ret = IRQ_HANDLED; | |
1099 | spi_writel(as, IDR, pending); | |
1100 | } | |
1101 | ||
1102 | return ret; | |
754ce4f2 HS |
1103 | } |
1104 | ||
1105 | static irqreturn_t | |
1ccc404a | 1106 | atmel_spi_pdc_interrupt(int irq, void *dev_id) |
754ce4f2 HS |
1107 | { |
1108 | struct spi_master *master = dev_id; | |
1109 | struct atmel_spi *as = spi_master_get_devdata(master); | |
754ce4f2 HS |
1110 | u32 status, pending, imr; |
1111 | int ret = IRQ_NONE; | |
1112 | ||
754ce4f2 HS |
1113 | imr = spi_readl(as, IMR); |
1114 | status = spi_readl(as, SR); | |
1115 | pending = status & imr; | |
1116 | ||
1117 | if (pending & SPI_BIT(OVRES)) { | |
754ce4f2 HS |
1118 | |
1119 | ret = IRQ_HANDLED; | |
1120 | ||
dc329442 | 1121 | spi_writel(as, IDR, (SPI_BIT(RXBUFF) | SPI_BIT(ENDRX) |
754ce4f2 HS |
1122 | | SPI_BIT(OVRES))); |
1123 | ||
754ce4f2 HS |
1124 | /* Clear any overrun happening while cleaning up */ |
1125 | spi_readl(as, SR); | |
1126 | ||
823cd045 | 1127 | as->done_status = -EIO; |
8090d6d1 WY |
1128 | |
1129 | complete(&as->xfer_completion); | |
1130 | ||
dc329442 | 1131 | } else if (pending & (SPI_BIT(RXBUFF) | SPI_BIT(ENDRX))) { |
754ce4f2 HS |
1132 | ret = IRQ_HANDLED; |
1133 | ||
1134 | spi_writel(as, IDR, pending); | |
1135 | ||
8090d6d1 | 1136 | complete(&as->xfer_completion); |
754ce4f2 HS |
1137 | } |
1138 | ||
754ce4f2 HS |
1139 | return ret; |
1140 | } | |
1141 | ||
754ce4f2 HS |
1142 | static int atmel_spi_setup(struct spi_device *spi) |
1143 | { | |
1144 | struct atmel_spi *as; | |
5ee36c98 | 1145 | struct atmel_spi_device *asd; |
d3b72c7e | 1146 | u32 csr; |
754ce4f2 | 1147 | unsigned int bits = spi->bits_per_word; |
754ce4f2 | 1148 | unsigned int npcs_pin; |
754ce4f2 HS |
1149 | |
1150 | as = spi_master_get_devdata(spi->master); | |
1151 | ||
defbd3b4 | 1152 | /* see notes above re chipselect */ |
d4820b74 | 1153 | if (!atmel_spi_is_v2(as) |
defbd3b4 DB |
1154 | && spi->chip_select == 0 |
1155 | && (spi->mode & SPI_CS_HIGH)) { | |
1156 | dev_dbg(&spi->dev, "setup: can't be active-high\n"); | |
1157 | return -EINVAL; | |
1158 | } | |
1159 | ||
d3b72c7e | 1160 | csr = SPI_BF(BITS, bits - 8); |
754ce4f2 HS |
1161 | if (spi->mode & SPI_CPOL) |
1162 | csr |= SPI_BIT(CPOL); | |
1163 | if (!(spi->mode & SPI_CPHA)) | |
1164 | csr |= SPI_BIT(NCPHA); | |
48203034 CP |
1165 | if (!as->use_cs_gpios) |
1166 | csr |= SPI_BIT(CSAAT); | |
754ce4f2 | 1167 | |
1eed29df HS |
1168 | /* DLYBS is mostly irrelevant since we manage chipselect using GPIOs. |
1169 | * | |
1170 | * DLYBCT would add delays between words, slowing down transfers. | |
1171 | * It could potentially be useful to cope with DMA bottlenecks, but | |
1172 | * in those cases it's probably best to just use a lower bitrate. | |
1173 | */ | |
1174 | csr |= SPI_BF(DLYBS, 0); | |
1175 | csr |= SPI_BF(DLYBCT, 0); | |
754ce4f2 HS |
1176 | |
1177 | /* chipselect must have been muxed as GPIO (e.g. in board setup) */ | |
67f08d69 | 1178 | npcs_pin = (unsigned long)spi->controller_data; |
850a5b67 | 1179 | |
48203034 CP |
1180 | if (!as->use_cs_gpios) |
1181 | npcs_pin = spi->chip_select; | |
1182 | else if (gpio_is_valid(spi->cs_gpio)) | |
850a5b67 JCPV |
1183 | npcs_pin = spi->cs_gpio; |
1184 | ||
5ee36c98 HS |
1185 | asd = spi->controller_state; |
1186 | if (!asd) { | |
1187 | asd = kzalloc(sizeof(struct atmel_spi_device), GFP_KERNEL); | |
1188 | if (!asd) | |
1189 | return -ENOMEM; | |
1190 | ||
96106200 | 1191 | if (as->use_cs_gpios) |
48203034 CP |
1192 | gpio_direction_output(npcs_pin, |
1193 | !(spi->mode & SPI_CS_HIGH)); | |
5ee36c98 HS |
1194 | |
1195 | asd->npcs_pin = npcs_pin; | |
1196 | spi->controller_state = asd; | |
754ce4f2 HS |
1197 | } |
1198 | ||
5ee36c98 HS |
1199 | asd->csr = csr; |
1200 | ||
754ce4f2 | 1201 | dev_dbg(&spi->dev, |
d3b72c7e RG |
1202 | "setup: bpw %u mode 0x%x -> csr%d %08x\n", |
1203 | bits, spi->mode, spi->chip_select, csr); | |
754ce4f2 | 1204 | |
d4820b74 | 1205 | if (!atmel_spi_is_v2(as)) |
5ee36c98 | 1206 | spi_writel(as, CSR0 + 4 * spi->chip_select, csr); |
754ce4f2 HS |
1207 | |
1208 | return 0; | |
1209 | } | |
1210 | ||
8090d6d1 WY |
1211 | static int atmel_spi_one_transfer(struct spi_master *master, |
1212 | struct spi_message *msg, | |
1213 | struct spi_transfer *xfer) | |
754ce4f2 HS |
1214 | { |
1215 | struct atmel_spi *as; | |
8090d6d1 | 1216 | struct spi_device *spi = msg->spi; |
b9d228f9 | 1217 | u8 bits; |
8090d6d1 | 1218 | u32 len; |
b9d228f9 | 1219 | struct atmel_spi_device *asd; |
8090d6d1 WY |
1220 | int timeout; |
1221 | int ret; | |
1369dea6 | 1222 | unsigned long dma_timeout; |
754ce4f2 | 1223 | |
8090d6d1 | 1224 | as = spi_master_get_devdata(master); |
754ce4f2 | 1225 | |
8090d6d1 WY |
1226 | if (!(xfer->tx_buf || xfer->rx_buf) && xfer->len) { |
1227 | dev_dbg(&spi->dev, "missing rx or tx buf\n"); | |
754ce4f2 | 1228 | return -EINVAL; |
8090d6d1 | 1229 | } |
754ce4f2 | 1230 | |
e8646580 JN |
1231 | asd = spi->controller_state; |
1232 | bits = (asd->csr >> 4) & 0xf; | |
1233 | if (bits != xfer->bits_per_word - 8) { | |
1234 | dev_dbg(&spi->dev, | |
8090d6d1 | 1235 | "you can't yet change bits_per_word in transfers\n"); |
e8646580 | 1236 | return -ENOPROTOOPT; |
8090d6d1 | 1237 | } |
754ce4f2 | 1238 | |
8090d6d1 WY |
1239 | /* |
1240 | * DMA map early, for performance (empties dcache ASAP) and | |
1241 | * better fault reporting. | |
1242 | */ | |
1243 | if ((!msg->is_dma_mapped) | |
04242ca4 | 1244 | && as->use_pdc) { |
8090d6d1 WY |
1245 | if (atmel_spi_dma_map_xfer(as, xfer) < 0) |
1246 | return -ENOMEM; | |
1247 | } | |
1248 | ||
1249 | atmel_spi_set_xfer_speed(as, msg->spi, xfer); | |
754ce4f2 | 1250 | |
8090d6d1 WY |
1251 | as->done_status = 0; |
1252 | as->current_transfer = xfer; | |
1253 | as->current_remaining_bytes = xfer->len; | |
1254 | while (as->current_remaining_bytes) { | |
1255 | reinit_completion(&as->xfer_completion); | |
1256 | ||
1257 | if (as->use_pdc) { | |
1258 | atmel_spi_pdc_next_xfer(master, msg, xfer); | |
1259 | } else if (atmel_spi_use_dma(as, xfer)) { | |
1260 | len = as->current_remaining_bytes; | |
1261 | ret = atmel_spi_next_xfer_dma_submit(master, | |
1262 | xfer, &len); | |
1263 | if (ret) { | |
1264 | dev_err(&spi->dev, | |
1265 | "unable to use DMA, fallback to PIO\n"); | |
1266 | atmel_spi_next_xfer_pio(master, xfer); | |
1267 | } else { | |
1268 | as->current_remaining_bytes -= len; | |
0c3b9748 AL |
1269 | if (as->current_remaining_bytes < 0) |
1270 | as->current_remaining_bytes = 0; | |
b9d228f9 | 1271 | } |
8090d6d1 WY |
1272 | } else { |
1273 | atmel_spi_next_xfer_pio(master, xfer); | |
b9d228f9 MB |
1274 | } |
1275 | ||
1676014e AS |
1276 | /* interrupts are disabled, so free the lock for schedule */ |
1277 | atmel_spi_unlock(as); | |
1369dea6 NMG |
1278 | dma_timeout = wait_for_completion_timeout(&as->xfer_completion, |
1279 | SPI_DMA_TIMEOUT); | |
1676014e | 1280 | atmel_spi_lock(as); |
1369dea6 NMG |
1281 | if (WARN_ON(dma_timeout == 0)) { |
1282 | dev_err(&spi->dev, "spi transfer timeout\n"); | |
8090d6d1 | 1283 | as->done_status = -EIO; |
f557c98b RG |
1284 | } |
1285 | ||
8090d6d1 WY |
1286 | if (as->done_status) |
1287 | break; | |
1288 | } | |
1289 | ||
1290 | if (as->done_status) { | |
1291 | if (as->use_pdc) { | |
1292 | dev_warn(master->dev.parent, | |
1293 | "overrun (%u/%u remaining)\n", | |
1294 | spi_readl(as, TCR), spi_readl(as, RCR)); | |
1295 | ||
1296 | /* | |
1297 | * Clean up DMA registers and make sure the data | |
1298 | * registers are empty. | |
1299 | */ | |
1300 | spi_writel(as, RNCR, 0); | |
1301 | spi_writel(as, TNCR, 0); | |
1302 | spi_writel(as, RCR, 0); | |
1303 | spi_writel(as, TCR, 0); | |
1304 | for (timeout = 1000; timeout; timeout--) | |
1305 | if (spi_readl(as, SR) & SPI_BIT(TXEMPTY)) | |
1306 | break; | |
1307 | if (!timeout) | |
1308 | dev_warn(master->dev.parent, | |
1309 | "timeout waiting for TXEMPTY"); | |
1310 | while (spi_readl(as, SR) & SPI_BIT(RDRF)) | |
1311 | spi_readl(as, RDR); | |
1312 | ||
1313 | /* Clear any overrun happening while cleaning up */ | |
1314 | spi_readl(as, SR); | |
1315 | ||
1316 | } else if (atmel_spi_use_dma(as, xfer)) { | |
768f3d9d | 1317 | atmel_spi_stop_dma(master); |
8090d6d1 WY |
1318 | } |
1319 | ||
1320 | if (!msg->is_dma_mapped | |
04242ca4 | 1321 | && as->use_pdc) |
8090d6d1 WY |
1322 | atmel_spi_dma_unmap_xfer(master, xfer); |
1323 | ||
1324 | return 0; | |
1325 | ||
1326 | } else { | |
1327 | /* only update length if no error */ | |
1328 | msg->actual_length += xfer->len; | |
1329 | } | |
1330 | ||
1331 | if (!msg->is_dma_mapped | |
04242ca4 | 1332 | && as->use_pdc) |
8090d6d1 WY |
1333 | atmel_spi_dma_unmap_xfer(master, xfer); |
1334 | ||
1335 | if (xfer->delay_usecs) | |
1336 | udelay(xfer->delay_usecs); | |
1337 | ||
1338 | if (xfer->cs_change) { | |
1339 | if (list_is_last(&xfer->transfer_list, | |
1340 | &msg->transfers)) { | |
1341 | as->keep_cs = true; | |
1342 | } else { | |
1343 | as->cs_active = !as->cs_active; | |
1344 | if (as->cs_active) | |
1345 | cs_activate(as, msg->spi); | |
1346 | else | |
1347 | cs_deactivate(as, msg->spi); | |
8da0859a | 1348 | } |
754ce4f2 HS |
1349 | } |
1350 | ||
8090d6d1 WY |
1351 | return 0; |
1352 | } | |
1353 | ||
1354 | static int atmel_spi_transfer_one_message(struct spi_master *master, | |
1355 | struct spi_message *msg) | |
1356 | { | |
1357 | struct atmel_spi *as; | |
1358 | struct spi_transfer *xfer; | |
1359 | struct spi_device *spi = msg->spi; | |
1360 | int ret = 0; | |
1361 | ||
1362 | as = spi_master_get_devdata(master); | |
1363 | ||
1364 | dev_dbg(&spi->dev, "new message %p submitted for %s\n", | |
1365 | msg, dev_name(&spi->dev)); | |
1366 | ||
8090d6d1 WY |
1367 | atmel_spi_lock(as); |
1368 | cs_activate(as, spi); | |
1369 | ||
1370 | as->cs_active = true; | |
1371 | as->keep_cs = false; | |
1372 | ||
1373 | msg->status = 0; | |
1374 | msg->actual_length = 0; | |
1375 | ||
1376 | list_for_each_entry(xfer, &msg->transfers, transfer_list) { | |
1377 | ret = atmel_spi_one_transfer(master, msg, xfer); | |
1378 | if (ret) | |
1379 | goto msg_done; | |
1380 | } | |
1381 | ||
1382 | if (as->use_pdc) | |
1383 | atmel_spi_disable_pdc_transfer(as); | |
1384 | ||
754ce4f2 | 1385 | list_for_each_entry(xfer, &msg->transfers, transfer_list) { |
8090d6d1 | 1386 | dev_dbg(&spi->dev, |
54f4c51c | 1387 | " xfer %p: len %u tx %p/%pad rx %p/%pad\n", |
754ce4f2 | 1388 | xfer, xfer->len, |
54f4c51c RD |
1389 | xfer->tx_buf, &xfer->tx_dma, |
1390 | xfer->rx_buf, &xfer->rx_dma); | |
754ce4f2 HS |
1391 | } |
1392 | ||
8090d6d1 WY |
1393 | msg_done: |
1394 | if (!as->keep_cs) | |
1395 | cs_deactivate(as, msg->spi); | |
754ce4f2 | 1396 | |
8aad7924 | 1397 | atmel_spi_unlock(as); |
754ce4f2 | 1398 | |
8090d6d1 WY |
1399 | msg->status = as->done_status; |
1400 | spi_finalize_current_message(spi->master); | |
1401 | ||
1402 | return ret; | |
754ce4f2 HS |
1403 | } |
1404 | ||
bb2d1c36 | 1405 | static void atmel_spi_cleanup(struct spi_device *spi) |
754ce4f2 | 1406 | { |
5ee36c98 | 1407 | struct atmel_spi_device *asd = spi->controller_state; |
defbd3b4 | 1408 | |
5ee36c98 | 1409 | if (!asd) |
defbd3b4 DB |
1410 | return; |
1411 | ||
5ee36c98 | 1412 | spi->controller_state = NULL; |
5ee36c98 | 1413 | kfree(asd); |
754ce4f2 HS |
1414 | } |
1415 | ||
d4820b74 WY |
1416 | static inline unsigned int atmel_get_version(struct atmel_spi *as) |
1417 | { | |
1418 | return spi_readl(as, VERSION) & 0x00000fff; | |
1419 | } | |
1420 | ||
1421 | static void atmel_get_caps(struct atmel_spi *as) | |
1422 | { | |
1423 | unsigned int version; | |
1424 | ||
1425 | version = atmel_get_version(as); | |
d4820b74 WY |
1426 | |
1427 | as->caps.is_spi2 = version > 0x121; | |
1428 | as->caps.has_wdrbt = version >= 0x210; | |
7094576c CP |
1429 | #ifdef CONFIG_SOC_SAM_V4_V5 |
1430 | /* | |
1431 | * Atmel SoCs based on ARM9 (SAM9x) cores should not use spi_map_buf() | |
1432 | * since this later function tries to map buffers with dma_map_sg() | |
1433 | * even if they have not been allocated inside DMA-safe areas. | |
1434 | * On SoCs based on Cortex A5 (SAMA5Dx), it works anyway because for | |
1435 | * those ARM cores, the data cache follows the PIPT model. | |
1436 | * Also the L2 cache controller of SAMA5D2 uses the PIPT model too. | |
1437 | * In case of PIPT caches, there cannot be cache aliases. | |
1438 | * However on ARM9 cores, the data cache follows the VIVT model, hence | |
1439 | * the cache aliases issue can occur when buffers are allocated from | |
1440 | * DMA-unsafe areas, by vmalloc() for instance, where cache coherency is | |
1441 | * not taken into account or at least not handled completely (cache | |
1442 | * lines of aliases are not invalidated). | |
1443 | * This is not a theorical issue: it was reproduced when trying to mount | |
1444 | * a UBI file-system on a at91sam9g35ek board. | |
1445 | */ | |
1446 | as->caps.has_dma_support = false; | |
1447 | #else | |
d4820b74 | 1448 | as->caps.has_dma_support = version >= 0x212; |
7094576c CP |
1449 | #endif |
1450 | as->caps.has_pdc_support = version < 0x212; | |
d4820b74 WY |
1451 | } |
1452 | ||
754ce4f2 | 1453 | /*-------------------------------------------------------------------------*/ |
96106200 NF |
1454 | static int atmel_spi_gpio_cs(struct platform_device *pdev) |
1455 | { | |
1456 | struct spi_master *master = platform_get_drvdata(pdev); | |
1457 | struct atmel_spi *as = spi_master_get_devdata(master); | |
1458 | struct device_node *np = master->dev.of_node; | |
1459 | int i; | |
1460 | int ret = 0; | |
1461 | int nb = 0; | |
1462 | ||
1463 | if (!as->use_cs_gpios) | |
1464 | return 0; | |
1465 | ||
1466 | if (!np) | |
1467 | return 0; | |
1468 | ||
1469 | nb = of_gpio_named_count(np, "cs-gpios"); | |
1470 | for (i = 0; i < nb; i++) { | |
1471 | int cs_gpio = of_get_named_gpio(pdev->dev.of_node, | |
1472 | "cs-gpios", i); | |
1473 | ||
b52b3484 DC |
1474 | if (cs_gpio == -EPROBE_DEFER) |
1475 | return cs_gpio; | |
96106200 | 1476 | |
b52b3484 DC |
1477 | if (gpio_is_valid(cs_gpio)) { |
1478 | ret = devm_gpio_request(&pdev->dev, cs_gpio, | |
1479 | dev_name(&pdev->dev)); | |
1480 | if (ret) | |
1481 | return ret; | |
1482 | } | |
96106200 NF |
1483 | } |
1484 | ||
1485 | return 0; | |
1486 | } | |
754ce4f2 | 1487 | |
05514c86 QS |
1488 | static void atmel_spi_init(struct atmel_spi *as) |
1489 | { | |
1490 | spi_writel(as, CR, SPI_BIT(SWRST)); | |
1491 | spi_writel(as, CR, SPI_BIT(SWRST)); /* AT91SAM9263 Rev B workaround */ | |
1492 | if (as->caps.has_wdrbt) { | |
1493 | spi_writel(as, MR, SPI_BIT(WDRBT) | SPI_BIT(MODFDIS) | |
1494 | | SPI_BIT(MSTR)); | |
1495 | } else { | |
1496 | spi_writel(as, MR, SPI_BIT(MSTR) | SPI_BIT(MODFDIS)); | |
1497 | } | |
1498 | ||
1499 | if (as->use_pdc) | |
1500 | spi_writel(as, PTCR, SPI_BIT(RXTDIS) | SPI_BIT(TXTDIS)); | |
1501 | spi_writel(as, CR, SPI_BIT(SPIEN)); | |
1502 | ||
1503 | if (as->fifo_size) | |
1504 | spi_writel(as, CR, SPI_BIT(FIFOEN)); | |
1505 | } | |
1506 | ||
fd4a319b | 1507 | static int atmel_spi_probe(struct platform_device *pdev) |
754ce4f2 HS |
1508 | { |
1509 | struct resource *regs; | |
1510 | int irq; | |
1511 | struct clk *clk; | |
1512 | int ret; | |
1513 | struct spi_master *master; | |
1514 | struct atmel_spi *as; | |
1515 | ||
5bdfd491 WY |
1516 | /* Select default pin state */ |
1517 | pinctrl_pm_select_default_state(&pdev->dev); | |
1518 | ||
754ce4f2 HS |
1519 | regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
1520 | if (!regs) | |
1521 | return -ENXIO; | |
1522 | ||
1523 | irq = platform_get_irq(pdev, 0); | |
1524 | if (irq < 0) | |
1525 | return irq; | |
1526 | ||
9f87d6f2 | 1527 | clk = devm_clk_get(&pdev->dev, "spi_clk"); |
754ce4f2 HS |
1528 | if (IS_ERR(clk)) |
1529 | return PTR_ERR(clk); | |
1530 | ||
1531 | /* setup spi core then atmel-specific driver state */ | |
1532 | ret = -ENOMEM; | |
a536d765 | 1533 | master = spi_alloc_master(&pdev->dev, sizeof(*as)); |
754ce4f2 HS |
1534 | if (!master) |
1535 | goto out_free; | |
1536 | ||
e7db06b5 DB |
1537 | /* the spi->mode bits understood by this driver: */ |
1538 | master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; | |
24778be2 | 1539 | master->bits_per_word_mask = SPI_BPW_RANGE_MASK(8, 16); |
850a5b67 | 1540 | master->dev.of_node = pdev->dev.of_node; |
754ce4f2 | 1541 | master->bus_num = pdev->id; |
850a5b67 | 1542 | master->num_chipselect = master->dev.of_node ? 0 : 4; |
754ce4f2 | 1543 | master->setup = atmel_spi_setup; |
7910d9af | 1544 | master->flags = (SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX); |
8090d6d1 | 1545 | master->transfer_one_message = atmel_spi_transfer_one_message; |
754ce4f2 | 1546 | master->cleanup = atmel_spi_cleanup; |
ce0c4caf | 1547 | master->auto_runtime_pm = true; |
7910d9af | 1548 | master->max_dma_len = SPI_MAX_DMA_XFER; |
04242ca4 | 1549 | master->can_dma = atmel_spi_can_dma; |
754ce4f2 HS |
1550 | platform_set_drvdata(pdev, master); |
1551 | ||
1552 | as = spi_master_get_devdata(master); | |
1553 | ||
754ce4f2 | 1554 | spin_lock_init(&as->lock); |
1ccc404a | 1555 | |
754ce4f2 | 1556 | as->pdev = pdev; |
31407478 | 1557 | as->regs = devm_ioremap_resource(&pdev->dev, regs); |
543c954d WY |
1558 | if (IS_ERR(as->regs)) { |
1559 | ret = PTR_ERR(as->regs); | |
7910d9af | 1560 | goto out_unmap_regs; |
543c954d | 1561 | } |
dfab30ee | 1562 | as->phybase = regs->start; |
754ce4f2 HS |
1563 | as->irq = irq; |
1564 | as->clk = clk; | |
754ce4f2 | 1565 | |
8090d6d1 WY |
1566 | init_completion(&as->xfer_completion); |
1567 | ||
d4820b74 WY |
1568 | atmel_get_caps(as); |
1569 | ||
48203034 CP |
1570 | as->use_cs_gpios = true; |
1571 | if (atmel_spi_is_v2(as) && | |
70f340df | 1572 | pdev->dev.of_node && |
48203034 CP |
1573 | !of_get_property(pdev->dev.of_node, "cs-gpios", NULL)) { |
1574 | as->use_cs_gpios = false; | |
1575 | master->num_chipselect = 4; | |
1576 | } | |
1577 | ||
96106200 NF |
1578 | ret = atmel_spi_gpio_cs(pdev); |
1579 | if (ret) | |
1580 | goto out_unmap_regs; | |
1581 | ||
1ccc404a NF |
1582 | as->use_dma = false; |
1583 | as->use_pdc = false; | |
1584 | if (as->caps.has_dma_support) { | |
768f3d9d | 1585 | ret = atmel_spi_configure_dma(master, as); |
04242ca4 | 1586 | if (ret == 0) { |
1ccc404a | 1587 | as->use_dma = true; |
04242ca4 | 1588 | } else if (ret == -EPROBE_DEFER) { |
5e9af37e | 1589 | return ret; |
04242ca4 | 1590 | } |
7094576c | 1591 | } else if (as->caps.has_pdc_support) { |
1ccc404a NF |
1592 | as->use_pdc = true; |
1593 | } | |
1594 | ||
1595 | if (as->caps.has_dma_support && !as->use_dma) | |
1596 | dev_info(&pdev->dev, "Atmel SPI Controller using PIO only\n"); | |
1597 | ||
1598 | if (as->use_pdc) { | |
9f87d6f2 JH |
1599 | ret = devm_request_irq(&pdev->dev, irq, atmel_spi_pdc_interrupt, |
1600 | 0, dev_name(&pdev->dev), master); | |
1ccc404a | 1601 | } else { |
9f87d6f2 JH |
1602 | ret = devm_request_irq(&pdev->dev, irq, atmel_spi_pio_interrupt, |
1603 | 0, dev_name(&pdev->dev), master); | |
1ccc404a | 1604 | } |
754ce4f2 HS |
1605 | if (ret) |
1606 | goto out_unmap_regs; | |
1607 | ||
1608 | /* Initialize the hardware */ | |
dfec4a6e BB |
1609 | ret = clk_prepare_enable(clk); |
1610 | if (ret) | |
de8cc234 | 1611 | goto out_free_irq; |
39fe33f9 BW |
1612 | |
1613 | as->spi_clk = clk_get_rate(clk); | |
1614 | ||
11f2764f CP |
1615 | as->fifo_size = 0; |
1616 | if (!of_property_read_u32(pdev->dev.of_node, "atmel,fifo-size", | |
1617 | &as->fifo_size)) { | |
1618 | dev_info(&pdev->dev, "Using FIFO (%u data)\n", as->fifo_size); | |
11f2764f CP |
1619 | } |
1620 | ||
05514c86 QS |
1621 | atmel_spi_init(as); |
1622 | ||
ce0c4caf WY |
1623 | pm_runtime_set_autosuspend_delay(&pdev->dev, AUTOSUSPEND_TIMEOUT); |
1624 | pm_runtime_use_autosuspend(&pdev->dev); | |
1625 | pm_runtime_set_active(&pdev->dev); | |
1626 | pm_runtime_enable(&pdev->dev); | |
1627 | ||
9f87d6f2 | 1628 | ret = devm_spi_register_master(&pdev->dev, master); |
754ce4f2 | 1629 | if (ret) |
1ccc404a | 1630 | goto out_free_dma; |
754ce4f2 | 1631 | |
ce24a513 | 1632 | /* go! */ |
6aba9c65 BS |
1633 | dev_info(&pdev->dev, "Atmel SPI Controller version 0x%x at 0x%08lx (irq %d)\n", |
1634 | atmel_get_version(as), (unsigned long)regs->start, | |
1635 | irq); | |
ce24a513 | 1636 | |
754ce4f2 HS |
1637 | return 0; |
1638 | ||
1ccc404a | 1639 | out_free_dma: |
ce0c4caf WY |
1640 | pm_runtime_disable(&pdev->dev); |
1641 | pm_runtime_set_suspended(&pdev->dev); | |
1642 | ||
1ccc404a | 1643 | if (as->use_dma) |
768f3d9d | 1644 | atmel_spi_release_dma(master); |
1ccc404a | 1645 | |
754ce4f2 | 1646 | spi_writel(as, CR, SPI_BIT(SWRST)); |
50d7d5bf | 1647 | spi_writel(as, CR, SPI_BIT(SWRST)); /* AT91SAM9263 Rev B workaround */ |
dfec4a6e | 1648 | clk_disable_unprepare(clk); |
de8cc234 | 1649 | out_free_irq: |
754ce4f2 | 1650 | out_unmap_regs: |
754ce4f2 | 1651 | out_free: |
754ce4f2 HS |
1652 | spi_master_put(master); |
1653 | return ret; | |
1654 | } | |
1655 | ||
fd4a319b | 1656 | static int atmel_spi_remove(struct platform_device *pdev) |
754ce4f2 HS |
1657 | { |
1658 | struct spi_master *master = platform_get_drvdata(pdev); | |
1659 | struct atmel_spi *as = spi_master_get_devdata(master); | |
754ce4f2 | 1660 | |
ce0c4caf WY |
1661 | pm_runtime_get_sync(&pdev->dev); |
1662 | ||
754ce4f2 HS |
1663 | /* reset the hardware and block queue progress */ |
1664 | spin_lock_irq(&as->lock); | |
1ccc404a | 1665 | if (as->use_dma) { |
768f3d9d NF |
1666 | atmel_spi_stop_dma(master); |
1667 | atmel_spi_release_dma(master); | |
1ccc404a NF |
1668 | } |
1669 | ||
754ce4f2 | 1670 | spi_writel(as, CR, SPI_BIT(SWRST)); |
50d7d5bf | 1671 | spi_writel(as, CR, SPI_BIT(SWRST)); /* AT91SAM9263 Rev B workaround */ |
754ce4f2 HS |
1672 | spi_readl(as, SR); |
1673 | spin_unlock_irq(&as->lock); | |
1674 | ||
dfec4a6e | 1675 | clk_disable_unprepare(as->clk); |
754ce4f2 | 1676 | |
ce0c4caf WY |
1677 | pm_runtime_put_noidle(&pdev->dev); |
1678 | pm_runtime_disable(&pdev->dev); | |
1679 | ||
754ce4f2 HS |
1680 | return 0; |
1681 | } | |
1682 | ||
ce0c4caf | 1683 | #ifdef CONFIG_PM |
c1ee8f3f WY |
1684 | static int atmel_spi_runtime_suspend(struct device *dev) |
1685 | { | |
1686 | struct spi_master *master = dev_get_drvdata(dev); | |
1687 | struct atmel_spi *as = spi_master_get_devdata(master); | |
1688 | ||
1689 | clk_disable_unprepare(as->clk); | |
1690 | pinctrl_pm_select_sleep_state(dev); | |
1691 | ||
1692 | return 0; | |
1693 | } | |
1694 | ||
1695 | static int atmel_spi_runtime_resume(struct device *dev) | |
1696 | { | |
1697 | struct spi_master *master = dev_get_drvdata(dev); | |
1698 | struct atmel_spi *as = spi_master_get_devdata(master); | |
1699 | ||
1700 | pinctrl_pm_select_default_state(dev); | |
1701 | ||
1702 | return clk_prepare_enable(as->clk); | |
1703 | } | |
1704 | ||
d630526d | 1705 | #ifdef CONFIG_PM_SLEEP |
ec60dd37 | 1706 | static int atmel_spi_suspend(struct device *dev) |
754ce4f2 | 1707 | { |
c1ee8f3f | 1708 | struct spi_master *master = dev_get_drvdata(dev); |
ba938f3a WY |
1709 | int ret; |
1710 | ||
1711 | /* Stop the queue running */ | |
1712 | ret = spi_master_suspend(master); | |
1713 | if (ret) { | |
1714 | dev_warn(dev, "cannot suspend master\n"); | |
1715 | return ret; | |
1716 | } | |
754ce4f2 | 1717 | |
c1ee8f3f WY |
1718 | if (!pm_runtime_suspended(dev)) |
1719 | atmel_spi_runtime_suspend(dev); | |
5bdfd491 | 1720 | |
754ce4f2 HS |
1721 | return 0; |
1722 | } | |
1723 | ||
ec60dd37 | 1724 | static int atmel_spi_resume(struct device *dev) |
754ce4f2 | 1725 | { |
c1ee8f3f | 1726 | struct spi_master *master = dev_get_drvdata(dev); |
e5380078 | 1727 | struct atmel_spi *as = spi_master_get_devdata(master); |
ba938f3a | 1728 | int ret; |
754ce4f2 | 1729 | |
e5380078 QS |
1730 | ret = clk_prepare_enable(as->clk); |
1731 | if (ret) | |
1732 | return ret; | |
1733 | ||
1734 | atmel_spi_init(as); | |
1735 | ||
1736 | clk_disable_unprepare(as->clk); | |
1737 | ||
ce0c4caf | 1738 | if (!pm_runtime_suspended(dev)) { |
c1ee8f3f | 1739 | ret = atmel_spi_runtime_resume(dev); |
ce0c4caf WY |
1740 | if (ret) |
1741 | return ret; | |
1742 | } | |
ba938f3a WY |
1743 | |
1744 | /* Start the queue running */ | |
1745 | ret = spi_master_resume(master); | |
1746 | if (ret) | |
1747 | dev_err(dev, "problem starting queue (%d)\n", ret); | |
1748 | ||
1749 | return ret; | |
754ce4f2 | 1750 | } |
d630526d | 1751 | #endif |
ce0c4caf WY |
1752 | |
1753 | static const struct dev_pm_ops atmel_spi_pm_ops = { | |
1754 | SET_SYSTEM_SLEEP_PM_OPS(atmel_spi_suspend, atmel_spi_resume) | |
1755 | SET_RUNTIME_PM_OPS(atmel_spi_runtime_suspend, | |
1756 | atmel_spi_runtime_resume, NULL) | |
1757 | }; | |
ec60dd37 | 1758 | #define ATMEL_SPI_PM_OPS (&atmel_spi_pm_ops) |
754ce4f2 | 1759 | #else |
ec60dd37 | 1760 | #define ATMEL_SPI_PM_OPS NULL |
754ce4f2 HS |
1761 | #endif |
1762 | ||
850a5b67 JCPV |
1763 | #if defined(CONFIG_OF) |
1764 | static const struct of_device_id atmel_spi_dt_ids[] = { | |
1765 | { .compatible = "atmel,at91rm9200-spi" }, | |
1766 | { /* sentinel */ } | |
1767 | }; | |
1768 | ||
1769 | MODULE_DEVICE_TABLE(of, atmel_spi_dt_ids); | |
1770 | #endif | |
754ce4f2 HS |
1771 | |
1772 | static struct platform_driver atmel_spi_driver = { | |
1773 | .driver = { | |
1774 | .name = "atmel_spi", | |
ec60dd37 | 1775 | .pm = ATMEL_SPI_PM_OPS, |
850a5b67 | 1776 | .of_match_table = of_match_ptr(atmel_spi_dt_ids), |
754ce4f2 | 1777 | }, |
1cb201af | 1778 | .probe = atmel_spi_probe, |
2deff8d6 | 1779 | .remove = atmel_spi_remove, |
754ce4f2 | 1780 | }; |
940ab889 | 1781 | module_platform_driver(atmel_spi_driver); |
754ce4f2 HS |
1782 | |
1783 | MODULE_DESCRIPTION("Atmel AT32/AT91 SPI Controller driver"); | |
e05503ef | 1784 | MODULE_AUTHOR("Haavard Skinnemoen (Atmel)"); |
754ce4f2 | 1785 | MODULE_LICENSE("GPL"); |
7e38c3c4 | 1786 | MODULE_ALIAS("platform:atmel_spi"); |