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Commit | Line | Data |
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c41aa3ce MS |
1 | /* |
2 | * Driver for I2C adapter in Rockchip RK3xxx SoC | |
3 | * | |
4 | * Max Schwarz <max.schwarz@online.de> | |
5 | * based on the patches by Rockchip Inc. | |
6 | * | |
7 | * This program is free software; you can redistribute it and/or modify | |
8 | * it under the terms of the GNU General Public License version 2 as | |
9 | * published by the Free Software Foundation. | |
10 | */ | |
11 | ||
12 | #include <linux/kernel.h> | |
13 | #include <linux/module.h> | |
14 | #include <linux/i2c.h> | |
15 | #include <linux/interrupt.h> | |
16 | #include <linux/errno.h> | |
17 | #include <linux/err.h> | |
18 | #include <linux/platform_device.h> | |
19 | #include <linux/io.h> | |
20 | #include <linux/of_address.h> | |
21 | #include <linux/of_irq.h> | |
22 | #include <linux/spinlock.h> | |
23 | #include <linux/clk.h> | |
24 | #include <linux/wait.h> | |
25 | #include <linux/mfd/syscon.h> | |
26 | #include <linux/regmap.h> | |
0285f8f5 | 27 | #include <linux/math64.h> |
c41aa3ce MS |
28 | |
29 | ||
30 | /* Register Map */ | |
31 | #define REG_CON 0x00 /* control register */ | |
32 | #define REG_CLKDIV 0x04 /* clock divisor register */ | |
33 | #define REG_MRXADDR 0x08 /* slave address for REGISTER_TX */ | |
34 | #define REG_MRXRADDR 0x0c /* slave register address for REGISTER_TX */ | |
35 | #define REG_MTXCNT 0x10 /* number of bytes to be transmitted */ | |
36 | #define REG_MRXCNT 0x14 /* number of bytes to be received */ | |
37 | #define REG_IEN 0x18 /* interrupt enable */ | |
38 | #define REG_IPD 0x1c /* interrupt pending */ | |
39 | #define REG_FCNT 0x20 /* finished count */ | |
40 | ||
41 | /* Data buffer offsets */ | |
42 | #define TXBUFFER_BASE 0x100 | |
43 | #define RXBUFFER_BASE 0x200 | |
44 | ||
45 | /* REG_CON bits */ | |
46 | #define REG_CON_EN BIT(0) | |
47 | enum { | |
48 | REG_CON_MOD_TX = 0, /* transmit data */ | |
49 | REG_CON_MOD_REGISTER_TX, /* select register and restart */ | |
50 | REG_CON_MOD_RX, /* receive data */ | |
51 | REG_CON_MOD_REGISTER_RX, /* broken: transmits read addr AND writes | |
52 | * register addr */ | |
53 | }; | |
54 | #define REG_CON_MOD(mod) ((mod) << 1) | |
55 | #define REG_CON_MOD_MASK (BIT(1) | BIT(2)) | |
56 | #define REG_CON_START BIT(3) | |
57 | #define REG_CON_STOP BIT(4) | |
58 | #define REG_CON_LASTACK BIT(5) /* 1: send NACK after last received byte */ | |
59 | #define REG_CON_ACTACK BIT(6) /* 1: stop if NACK is received */ | |
60 | ||
a8a7d09e | 61 | #define REG_CON_TUNING_MASK GENMASK_ULL(15, 8) |
7e086c3f DW |
62 | |
63 | #define REG_CON_SDA_CFG(cfg) ((cfg) << 8) | |
64 | #define REG_CON_STA_CFG(cfg) ((cfg) << 12) | |
65 | #define REG_CON_STO_CFG(cfg) ((cfg) << 14) | |
66 | ||
c41aa3ce MS |
67 | /* REG_MRXADDR bits */ |
68 | #define REG_MRXADDR_VALID(x) BIT(24 + (x)) /* [x*8+7:x*8] of MRX[R]ADDR valid */ | |
69 | ||
70 | /* REG_IEN/REG_IPD bits */ | |
71 | #define REG_INT_BTF BIT(0) /* a byte was transmitted */ | |
72 | #define REG_INT_BRF BIT(1) /* a byte was received */ | |
73 | #define REG_INT_MBTF BIT(2) /* master data transmit finished */ | |
74 | #define REG_INT_MBRF BIT(3) /* master data receive finished */ | |
75 | #define REG_INT_START BIT(4) /* START condition generated */ | |
76 | #define REG_INT_STOP BIT(5) /* STOP condition generated */ | |
77 | #define REG_INT_NAKRCV BIT(6) /* NACK received */ | |
78 | #define REG_INT_ALL 0x7f | |
79 | ||
80 | /* Constants */ | |
4489750f | 81 | #define WAIT_TIMEOUT 1000 /* ms */ |
c41aa3ce MS |
82 | #define DEFAULT_SCL_RATE (100 * 1000) /* Hz */ |
83 | ||
b58fd3be DW |
84 | /** |
85 | * struct i2c_spec_values: | |
7e086c3f | 86 | * @min_hold_start_ns: min hold time (repeated) START condition |
b58fd3be DW |
87 | * @min_low_ns: min LOW period of the SCL clock |
88 | * @min_high_ns: min HIGH period of the SCL cloc | |
89 | * @min_setup_start_ns: min set-up time for a repeated START conditio | |
90 | * @max_data_hold_ns: max data hold time | |
7e086c3f DW |
91 | * @min_data_setup_ns: min data set-up time |
92 | * @min_setup_stop_ns: min set-up time for STOP condition | |
93 | * @min_hold_buffer_ns: min bus free time between a STOP and | |
94 | * START condition | |
b58fd3be DW |
95 | */ |
96 | struct i2c_spec_values { | |
7e086c3f | 97 | unsigned long min_hold_start_ns; |
b58fd3be DW |
98 | unsigned long min_low_ns; |
99 | unsigned long min_high_ns; | |
100 | unsigned long min_setup_start_ns; | |
101 | unsigned long max_data_hold_ns; | |
7e086c3f DW |
102 | unsigned long min_data_setup_ns; |
103 | unsigned long min_setup_stop_ns; | |
104 | unsigned long min_hold_buffer_ns; | |
b58fd3be DW |
105 | }; |
106 | ||
107 | static const struct i2c_spec_values standard_mode_spec = { | |
7e086c3f | 108 | .min_hold_start_ns = 4000, |
b58fd3be DW |
109 | .min_low_ns = 4700, |
110 | .min_high_ns = 4000, | |
111 | .min_setup_start_ns = 4700, | |
112 | .max_data_hold_ns = 3450, | |
7e086c3f DW |
113 | .min_data_setup_ns = 250, |
114 | .min_setup_stop_ns = 4000, | |
115 | .min_hold_buffer_ns = 4700, | |
b58fd3be DW |
116 | }; |
117 | ||
118 | static const struct i2c_spec_values fast_mode_spec = { | |
7e086c3f | 119 | .min_hold_start_ns = 600, |
b58fd3be DW |
120 | .min_low_ns = 1300, |
121 | .min_high_ns = 600, | |
122 | .min_setup_start_ns = 600, | |
123 | .max_data_hold_ns = 900, | |
7e086c3f DW |
124 | .min_data_setup_ns = 100, |
125 | .min_setup_stop_ns = 600, | |
126 | .min_hold_buffer_ns = 1300, | |
b58fd3be DW |
127 | }; |
128 | ||
a02f3d08 DW |
129 | static const struct i2c_spec_values fast_mode_plus_spec = { |
130 | .min_hold_start_ns = 260, | |
131 | .min_low_ns = 500, | |
132 | .min_high_ns = 260, | |
133 | .min_setup_start_ns = 260, | |
134 | .max_data_hold_ns = 400, | |
135 | .min_data_setup_ns = 50, | |
136 | .min_setup_stop_ns = 260, | |
137 | .min_hold_buffer_ns = 500, | |
138 | }; | |
139 | ||
e26747bf DW |
140 | /** |
141 | * struct rk3x_i2c_calced_timings: | |
142 | * @div_low: Divider output for low | |
143 | * @div_high: Divider output for high | |
7e086c3f DW |
144 | * @tuning: Used to adjust setup/hold data time, |
145 | * setup/hold start time and setup stop time for | |
146 | * v1's calc_timings, the tuning should all be 0 | |
147 | * for old hardware anyone using v0's calc_timings. | |
e26747bf DW |
148 | */ |
149 | struct rk3x_i2c_calced_timings { | |
150 | unsigned long div_low; | |
151 | unsigned long div_high; | |
7e086c3f | 152 | unsigned int tuning; |
e26747bf DW |
153 | }; |
154 | ||
c41aa3ce MS |
155 | enum rk3x_i2c_state { |
156 | STATE_IDLE, | |
157 | STATE_START, | |
158 | STATE_READ, | |
159 | STATE_WRITE, | |
160 | STATE_STOP | |
161 | }; | |
162 | ||
163 | /** | |
164 | * @grf_offset: offset inside the grf regmap for setting the i2c type | |
7e086c3f | 165 | * @calc_timings: Callback function for i2c timing information calculated |
c41aa3ce MS |
166 | */ |
167 | struct rk3x_i2c_soc_data { | |
168 | int grf_offset; | |
7e086c3f DW |
169 | int (*calc_timings)(unsigned long, struct i2c_timings *, |
170 | struct rk3x_i2c_calced_timings *); | |
c41aa3ce MS |
171 | }; |
172 | ||
0a6ad2f9 DW |
173 | /** |
174 | * struct rk3x_i2c - private data of the controller | |
175 | * @adap: corresponding I2C adapter | |
176 | * @dev: device for this controller | |
177 | * @soc_data: related soc data struct | |
178 | * @regs: virtual memory area | |
7e086c3f DW |
179 | * @clk: function clk for rk3399 or function & Bus clks for others |
180 | * @pclk: Bus clk for rk3399 | |
0a6ad2f9 DW |
181 | * @clk_rate_nb: i2c clk rate change notify |
182 | * @t: I2C known timing information | |
183 | * @lock: spinlock for the i2c bus | |
184 | * @wait: the waitqueue to wait for i2c transfer | |
185 | * @busy: the condition for the event to wait for | |
186 | * @msg: current i2c message | |
187 | * @addr: addr of i2c slave device | |
188 | * @mode: mode of i2c transfer | |
189 | * @is_last_msg: flag determines whether it is the last msg in this transfer | |
190 | * @state: state of i2c transfer | |
191 | * @processed: byte length which has been send or received | |
192 | * @error: error code for i2c transfer | |
193 | */ | |
c41aa3ce MS |
194 | struct rk3x_i2c { |
195 | struct i2c_adapter adap; | |
196 | struct device *dev; | |
197 | struct rk3x_i2c_soc_data *soc_data; | |
198 | ||
199 | /* Hardware resources */ | |
200 | void __iomem *regs; | |
201 | struct clk *clk; | |
7e086c3f | 202 | struct clk *pclk; |
249051f4 | 203 | struct notifier_block clk_rate_nb; |
c41aa3ce MS |
204 | |
205 | /* Settings */ | |
1ab92956 | 206 | struct i2c_timings t; |
c41aa3ce MS |
207 | |
208 | /* Synchronization & notification */ | |
209 | spinlock_t lock; | |
210 | wait_queue_head_t wait; | |
211 | bool busy; | |
212 | ||
213 | /* Current message */ | |
214 | struct i2c_msg *msg; | |
215 | u8 addr; | |
216 | unsigned int mode; | |
217 | bool is_last_msg; | |
218 | ||
219 | /* I2C state machine */ | |
220 | enum rk3x_i2c_state state; | |
0a6ad2f9 | 221 | unsigned int processed; |
c41aa3ce MS |
222 | int error; |
223 | }; | |
224 | ||
225 | static inline void i2c_writel(struct rk3x_i2c *i2c, u32 value, | |
226 | unsigned int offset) | |
227 | { | |
228 | writel(value, i2c->regs + offset); | |
229 | } | |
230 | ||
231 | static inline u32 i2c_readl(struct rk3x_i2c *i2c, unsigned int offset) | |
232 | { | |
233 | return readl(i2c->regs + offset); | |
234 | } | |
235 | ||
236 | /* Reset all interrupt pending bits */ | |
237 | static inline void rk3x_i2c_clean_ipd(struct rk3x_i2c *i2c) | |
238 | { | |
239 | i2c_writel(i2c, REG_INT_ALL, REG_IPD); | |
240 | } | |
241 | ||
242 | /** | |
243 | * Generate a START condition, which triggers a REG_INT_START interrupt. | |
244 | */ | |
245 | static void rk3x_i2c_start(struct rk3x_i2c *i2c) | |
246 | { | |
7e086c3f | 247 | u32 val = i2c_readl(i2c, REG_CON) & REG_CON_TUNING_MASK; |
c41aa3ce | 248 | |
c41aa3ce MS |
249 | i2c_writel(i2c, REG_INT_START, REG_IEN); |
250 | ||
251 | /* enable adapter with correct mode, send START condition */ | |
7e086c3f | 252 | val |= REG_CON_EN | REG_CON_MOD(i2c->mode) | REG_CON_START; |
c41aa3ce MS |
253 | |
254 | /* if we want to react to NACK, set ACTACK bit */ | |
255 | if (!(i2c->msg->flags & I2C_M_IGNORE_NAK)) | |
256 | val |= REG_CON_ACTACK; | |
257 | ||
258 | i2c_writel(i2c, val, REG_CON); | |
259 | } | |
260 | ||
261 | /** | |
262 | * Generate a STOP condition, which triggers a REG_INT_STOP interrupt. | |
263 | * | |
264 | * @error: Error code to return in rk3x_i2c_xfer | |
265 | */ | |
266 | static void rk3x_i2c_stop(struct rk3x_i2c *i2c, int error) | |
267 | { | |
268 | unsigned int ctrl; | |
269 | ||
270 | i2c->processed = 0; | |
271 | i2c->msg = NULL; | |
272 | i2c->error = error; | |
273 | ||
274 | if (i2c->is_last_msg) { | |
275 | /* Enable stop interrupt */ | |
276 | i2c_writel(i2c, REG_INT_STOP, REG_IEN); | |
277 | ||
278 | i2c->state = STATE_STOP; | |
279 | ||
280 | ctrl = i2c_readl(i2c, REG_CON); | |
281 | ctrl |= REG_CON_STOP; | |
282 | i2c_writel(i2c, ctrl, REG_CON); | |
283 | } else { | |
284 | /* Signal rk3x_i2c_xfer to start the next message. */ | |
285 | i2c->busy = false; | |
286 | i2c->state = STATE_IDLE; | |
287 | ||
288 | /* | |
289 | * The HW is actually not capable of REPEATED START. But we can | |
290 | * get the intended effect by resetting its internal state | |
291 | * and issuing an ordinary START. | |
292 | */ | |
7e086c3f DW |
293 | ctrl = i2c_readl(i2c, REG_CON) & REG_CON_TUNING_MASK; |
294 | i2c_writel(i2c, ctrl, REG_CON); | |
c41aa3ce MS |
295 | |
296 | /* signal that we are finished with the current msg */ | |
297 | wake_up(&i2c->wait); | |
298 | } | |
299 | } | |
300 | ||
301 | /** | |
302 | * Setup a read according to i2c->msg | |
303 | */ | |
304 | static void rk3x_i2c_prepare_read(struct rk3x_i2c *i2c) | |
305 | { | |
306 | unsigned int len = i2c->msg->len - i2c->processed; | |
307 | u32 con; | |
308 | ||
309 | con = i2c_readl(i2c, REG_CON); | |
310 | ||
311 | /* | |
312 | * The hw can read up to 32 bytes at a time. If we need more than one | |
313 | * chunk, send an ACK after the last byte of the current chunk. | |
314 | */ | |
29209338 | 315 | if (len > 32) { |
c41aa3ce MS |
316 | len = 32; |
317 | con &= ~REG_CON_LASTACK; | |
318 | } else { | |
319 | con |= REG_CON_LASTACK; | |
320 | } | |
321 | ||
322 | /* make sure we are in plain RX mode if we read a second chunk */ | |
323 | if (i2c->processed != 0) { | |
324 | con &= ~REG_CON_MOD_MASK; | |
325 | con |= REG_CON_MOD(REG_CON_MOD_RX); | |
326 | } | |
327 | ||
328 | i2c_writel(i2c, con, REG_CON); | |
329 | i2c_writel(i2c, len, REG_MRXCNT); | |
330 | } | |
331 | ||
332 | /** | |
333 | * Fill the transmit buffer with data from i2c->msg | |
334 | */ | |
335 | static void rk3x_i2c_fill_transmit_buf(struct rk3x_i2c *i2c) | |
336 | { | |
337 | unsigned int i, j; | |
338 | u32 cnt = 0; | |
339 | u32 val; | |
340 | u8 byte; | |
341 | ||
342 | for (i = 0; i < 8; ++i) { | |
343 | val = 0; | |
344 | for (j = 0; j < 4; ++j) { | |
cf27020d | 345 | if ((i2c->processed == i2c->msg->len) && (cnt != 0)) |
c41aa3ce MS |
346 | break; |
347 | ||
348 | if (i2c->processed == 0 && cnt == 0) | |
349 | byte = (i2c->addr & 0x7f) << 1; | |
350 | else | |
351 | byte = i2c->msg->buf[i2c->processed++]; | |
352 | ||
353 | val |= byte << (j * 8); | |
354 | cnt++; | |
355 | } | |
356 | ||
357 | i2c_writel(i2c, val, TXBUFFER_BASE + 4 * i); | |
358 | ||
359 | if (i2c->processed == i2c->msg->len) | |
360 | break; | |
361 | } | |
362 | ||
363 | i2c_writel(i2c, cnt, REG_MTXCNT); | |
364 | } | |
365 | ||
366 | ||
367 | /* IRQ handlers for individual states */ | |
368 | ||
369 | static void rk3x_i2c_handle_start(struct rk3x_i2c *i2c, unsigned int ipd) | |
370 | { | |
371 | if (!(ipd & REG_INT_START)) { | |
372 | rk3x_i2c_stop(i2c, -EIO); | |
373 | dev_warn(i2c->dev, "unexpected irq in START: 0x%x\n", ipd); | |
374 | rk3x_i2c_clean_ipd(i2c); | |
375 | return; | |
376 | } | |
377 | ||
378 | /* ack interrupt */ | |
379 | i2c_writel(i2c, REG_INT_START, REG_IPD); | |
380 | ||
381 | /* disable start bit */ | |
382 | i2c_writel(i2c, i2c_readl(i2c, REG_CON) & ~REG_CON_START, REG_CON); | |
383 | ||
384 | /* enable appropriate interrupts and transition */ | |
385 | if (i2c->mode == REG_CON_MOD_TX) { | |
386 | i2c_writel(i2c, REG_INT_MBTF | REG_INT_NAKRCV, REG_IEN); | |
387 | i2c->state = STATE_WRITE; | |
388 | rk3x_i2c_fill_transmit_buf(i2c); | |
389 | } else { | |
390 | /* in any other case, we are going to be reading. */ | |
391 | i2c_writel(i2c, REG_INT_MBRF | REG_INT_NAKRCV, REG_IEN); | |
392 | i2c->state = STATE_READ; | |
393 | rk3x_i2c_prepare_read(i2c); | |
394 | } | |
395 | } | |
396 | ||
397 | static void rk3x_i2c_handle_write(struct rk3x_i2c *i2c, unsigned int ipd) | |
398 | { | |
399 | if (!(ipd & REG_INT_MBTF)) { | |
400 | rk3x_i2c_stop(i2c, -EIO); | |
401 | dev_err(i2c->dev, "unexpected irq in WRITE: 0x%x\n", ipd); | |
402 | rk3x_i2c_clean_ipd(i2c); | |
403 | return; | |
404 | } | |
405 | ||
406 | /* ack interrupt */ | |
407 | i2c_writel(i2c, REG_INT_MBTF, REG_IPD); | |
408 | ||
409 | /* are we finished? */ | |
410 | if (i2c->processed == i2c->msg->len) | |
411 | rk3x_i2c_stop(i2c, i2c->error); | |
412 | else | |
413 | rk3x_i2c_fill_transmit_buf(i2c); | |
414 | } | |
415 | ||
416 | static void rk3x_i2c_handle_read(struct rk3x_i2c *i2c, unsigned int ipd) | |
417 | { | |
418 | unsigned int i; | |
419 | unsigned int len = i2c->msg->len - i2c->processed; | |
420 | u32 uninitialized_var(val); | |
421 | u8 byte; | |
422 | ||
423 | /* we only care for MBRF here. */ | |
424 | if (!(ipd & REG_INT_MBRF)) | |
425 | return; | |
426 | ||
427 | /* ack interrupt */ | |
428 | i2c_writel(i2c, REG_INT_MBRF, REG_IPD); | |
429 | ||
5da4309f | 430 | /* Can only handle a maximum of 32 bytes at a time */ |
431 | if (len > 32) | |
432 | len = 32; | |
433 | ||
c41aa3ce MS |
434 | /* read the data from receive buffer */ |
435 | for (i = 0; i < len; ++i) { | |
436 | if (i % 4 == 0) | |
437 | val = i2c_readl(i2c, RXBUFFER_BASE + (i / 4) * 4); | |
438 | ||
439 | byte = (val >> ((i % 4) * 8)) & 0xff; | |
440 | i2c->msg->buf[i2c->processed++] = byte; | |
441 | } | |
442 | ||
443 | /* are we finished? */ | |
444 | if (i2c->processed == i2c->msg->len) | |
445 | rk3x_i2c_stop(i2c, i2c->error); | |
446 | else | |
447 | rk3x_i2c_prepare_read(i2c); | |
448 | } | |
449 | ||
450 | static void rk3x_i2c_handle_stop(struct rk3x_i2c *i2c, unsigned int ipd) | |
451 | { | |
452 | unsigned int con; | |
453 | ||
454 | if (!(ipd & REG_INT_STOP)) { | |
455 | rk3x_i2c_stop(i2c, -EIO); | |
456 | dev_err(i2c->dev, "unexpected irq in STOP: 0x%x\n", ipd); | |
457 | rk3x_i2c_clean_ipd(i2c); | |
458 | return; | |
459 | } | |
460 | ||
461 | /* ack interrupt */ | |
462 | i2c_writel(i2c, REG_INT_STOP, REG_IPD); | |
463 | ||
464 | /* disable STOP bit */ | |
465 | con = i2c_readl(i2c, REG_CON); | |
466 | con &= ~REG_CON_STOP; | |
467 | i2c_writel(i2c, con, REG_CON); | |
468 | ||
469 | i2c->busy = false; | |
470 | i2c->state = STATE_IDLE; | |
471 | ||
472 | /* signal rk3x_i2c_xfer that we are finished */ | |
473 | wake_up(&i2c->wait); | |
474 | } | |
475 | ||
476 | static irqreturn_t rk3x_i2c_irq(int irqno, void *dev_id) | |
477 | { | |
478 | struct rk3x_i2c *i2c = dev_id; | |
479 | unsigned int ipd; | |
480 | ||
481 | spin_lock(&i2c->lock); | |
482 | ||
483 | ipd = i2c_readl(i2c, REG_IPD); | |
484 | if (i2c->state == STATE_IDLE) { | |
485 | dev_warn(i2c->dev, "irq in STATE_IDLE, ipd = 0x%x\n", ipd); | |
486 | rk3x_i2c_clean_ipd(i2c); | |
487 | goto out; | |
488 | } | |
489 | ||
490 | dev_dbg(i2c->dev, "IRQ: state %d, ipd: %x\n", i2c->state, ipd); | |
491 | ||
492 | /* Clean interrupt bits we don't care about */ | |
493 | ipd &= ~(REG_INT_BRF | REG_INT_BTF); | |
494 | ||
495 | if (ipd & REG_INT_NAKRCV) { | |
496 | /* | |
497 | * We got a NACK in the last operation. Depending on whether | |
498 | * IGNORE_NAK is set, we have to stop the operation and report | |
499 | * an error. | |
500 | */ | |
501 | i2c_writel(i2c, REG_INT_NAKRCV, REG_IPD); | |
502 | ||
503 | ipd &= ~REG_INT_NAKRCV; | |
504 | ||
505 | if (!(i2c->msg->flags & I2C_M_IGNORE_NAK)) | |
506 | rk3x_i2c_stop(i2c, -ENXIO); | |
507 | } | |
508 | ||
509 | /* is there anything left to handle? */ | |
29209338 | 510 | if ((ipd & REG_INT_ALL) == 0) |
c41aa3ce MS |
511 | goto out; |
512 | ||
513 | switch (i2c->state) { | |
514 | case STATE_START: | |
515 | rk3x_i2c_handle_start(i2c, ipd); | |
516 | break; | |
517 | case STATE_WRITE: | |
518 | rk3x_i2c_handle_write(i2c, ipd); | |
519 | break; | |
520 | case STATE_READ: | |
521 | rk3x_i2c_handle_read(i2c, ipd); | |
522 | break; | |
523 | case STATE_STOP: | |
524 | rk3x_i2c_handle_stop(i2c, ipd); | |
525 | break; | |
526 | case STATE_IDLE: | |
527 | break; | |
528 | } | |
529 | ||
530 | out: | |
531 | spin_unlock(&i2c->lock); | |
532 | return IRQ_HANDLED; | |
533 | } | |
534 | ||
b58fd3be DW |
535 | /** |
536 | * Get timing values of I2C specification | |
537 | * | |
538 | * @speed: Desired SCL frequency | |
539 | * | |
540 | * Returns: Matched i2c spec values. | |
541 | */ | |
542 | static const struct i2c_spec_values *rk3x_i2c_get_spec(unsigned int speed) | |
543 | { | |
544 | if (speed <= 100000) | |
545 | return &standard_mode_spec; | |
a02f3d08 | 546 | else if (speed <= 400000) |
b58fd3be | 547 | return &fast_mode_spec; |
a02f3d08 DW |
548 | else |
549 | return &fast_mode_plus_spec; | |
b58fd3be DW |
550 | } |
551 | ||
249051f4 MS |
552 | /** |
553 | * Calculate divider values for desired SCL frequency | |
554 | * | |
555 | * @clk_rate: I2C input clock rate | |
e26747bf DW |
556 | * @t: Known I2C timing information |
557 | * @t_calc: Caculated rk3x private timings that would be written into regs | |
249051f4 MS |
558 | * |
559 | * Returns: 0 on success, -EINVAL if the goal SCL rate is too slow. In that case | |
560 | * a best-effort divider value is returned in divs. If the target rate is | |
561 | * too high, we silently use the highest possible rate. | |
562 | */ | |
7e086c3f DW |
563 | static int rk3x_i2c_v0_calc_timings(unsigned long clk_rate, |
564 | struct i2c_timings *t, | |
565 | struct rk3x_i2c_calced_timings *t_calc) | |
c41aa3ce | 566 | { |
1330e291 | 567 | unsigned long min_low_ns, min_high_ns; |
0285f8f5 | 568 | unsigned long max_low_ns, min_total_ns; |
569 | ||
249051f4 | 570 | unsigned long clk_rate_khz, scl_rate_khz; |
0285f8f5 | 571 | |
572 | unsigned long min_low_div, min_high_div; | |
573 | unsigned long max_low_div; | |
574 | ||
575 | unsigned long min_div_for_hold, min_total_div; | |
576 | unsigned long extra_div, extra_low_div, ideal_low_div; | |
577 | ||
b58fd3be DW |
578 | unsigned long data_hold_buffer_ns = 50; |
579 | const struct i2c_spec_values *spec; | |
249051f4 MS |
580 | int ret = 0; |
581 | ||
0285f8f5 | 582 | /* Only support standard-mode and fast-mode */ |
1ab92956 DW |
583 | if (WARN_ON(t->bus_freq_hz > 400000)) |
584 | t->bus_freq_hz = 400000; | |
0285f8f5 | 585 | |
586 | /* prevent scl_rate_khz from becoming 0 */ | |
1ab92956 DW |
587 | if (WARN_ON(t->bus_freq_hz < 1000)) |
588 | t->bus_freq_hz = 1000; | |
c41aa3ce | 589 | |
0285f8f5 | 590 | /* |
1330e291 | 591 | * min_low_ns: The minimum number of ns we need to hold low to |
592 | * meet I2C specification, should include fall time. | |
593 | * min_high_ns: The minimum number of ns we need to hold high to | |
594 | * meet I2C specification, should include rise time. | |
595 | * max_low_ns: The maximum number of ns we can hold low to meet | |
596 | * I2C specification. | |
0285f8f5 | 597 | * |
1330e291 | 598 | * Note: max_low_ns should be (maximum data hold time * 2 - buffer) |
0285f8f5 | 599 | * This is because the i2c host on Rockchip holds the data line |
600 | * for half the low time. | |
b4a7bd7a | 601 | */ |
b58fd3be DW |
602 | spec = rk3x_i2c_get_spec(t->bus_freq_hz); |
603 | min_high_ns = t->scl_rise_ns + spec->min_high_ns; | |
387f0de6 DA |
604 | |
605 | /* | |
606 | * Timings for repeated start: | |
607 | * - controller appears to drop SDA at .875x (7/8) programmed clk high. | |
608 | * - controller appears to keep SCL high for 2x programmed clk high. | |
609 | * | |
610 | * We need to account for those rules in picking our "high" time so | |
611 | * we meet tSU;STA and tHD;STA times. | |
612 | */ | |
b58fd3be DW |
613 | min_high_ns = max(min_high_ns, DIV_ROUND_UP( |
614 | (t->scl_rise_ns + spec->min_setup_start_ns) * 1000, 875)); | |
615 | min_high_ns = max(min_high_ns, DIV_ROUND_UP( | |
616 | (t->scl_rise_ns + spec->min_setup_start_ns + t->sda_fall_ns + | |
617 | spec->min_high_ns), 2)); | |
618 | ||
619 | min_low_ns = t->scl_fall_ns + spec->min_low_ns; | |
620 | max_low_ns = spec->max_data_hold_ns * 2 - data_hold_buffer_ns; | |
0285f8f5 | 621 | min_total_ns = min_low_ns + min_high_ns; |
622 | ||
623 | /* Adjust to avoid overflow */ | |
249051f4 | 624 | clk_rate_khz = DIV_ROUND_UP(clk_rate, 1000); |
1ab92956 | 625 | scl_rate_khz = t->bus_freq_hz / 1000; |
0285f8f5 | 626 | |
627 | /* | |
628 | * We need the total div to be >= this number | |
629 | * so we don't clock too fast. | |
630 | */ | |
249051f4 | 631 | min_total_div = DIV_ROUND_UP(clk_rate_khz, scl_rate_khz * 8); |
0285f8f5 | 632 | |
633 | /* These are the min dividers needed for min hold times. */ | |
249051f4 MS |
634 | min_low_div = DIV_ROUND_UP(clk_rate_khz * min_low_ns, 8 * 1000000); |
635 | min_high_div = DIV_ROUND_UP(clk_rate_khz * min_high_ns, 8 * 1000000); | |
0285f8f5 | 636 | min_div_for_hold = (min_low_div + min_high_div); |
637 | ||
638 | /* | |
1330e291 | 639 | * This is the maximum divider so we don't go over the maximum. |
640 | * We don't round up here (we round down) since this is a maximum. | |
0285f8f5 | 641 | */ |
249051f4 | 642 | max_low_div = clk_rate_khz * max_low_ns / (8 * 1000000); |
0285f8f5 | 643 | |
644 | if (min_low_div > max_low_div) { | |
645 | WARN_ONCE(true, | |
646 | "Conflicting, min_low_div %lu, max_low_div %lu\n", | |
647 | min_low_div, max_low_div); | |
648 | max_low_div = min_low_div; | |
649 | } | |
650 | ||
651 | if (min_div_for_hold > min_total_div) { | |
652 | /* | |
653 | * Time needed to meet hold requirements is important. | |
654 | * Just use that. | |
655 | */ | |
e26747bf DW |
656 | t_calc->div_low = min_low_div; |
657 | t_calc->div_high = min_high_div; | |
0285f8f5 | 658 | } else { |
659 | /* | |
660 | * We've got to distribute some time among the low and high | |
661 | * so we don't run too fast. | |
662 | */ | |
663 | extra_div = min_total_div - min_div_for_hold; | |
664 | ||
665 | /* | |
666 | * We'll try to split things up perfectly evenly, | |
667 | * biasing slightly towards having a higher div | |
668 | * for low (spend more time low). | |
669 | */ | |
249051f4 | 670 | ideal_low_div = DIV_ROUND_UP(clk_rate_khz * min_low_ns, |
0285f8f5 | 671 | scl_rate_khz * 8 * min_total_ns); |
672 | ||
1330e291 | 673 | /* Don't allow it to go over the maximum */ |
0285f8f5 | 674 | if (ideal_low_div > max_low_div) |
675 | ideal_low_div = max_low_div; | |
c41aa3ce | 676 | |
0285f8f5 | 677 | /* |
678 | * Handle when the ideal low div is going to take up | |
679 | * more than we have. | |
680 | */ | |
681 | if (ideal_low_div > min_low_div + extra_div) | |
682 | ideal_low_div = min_low_div + extra_div; | |
683 | ||
684 | /* Give low the "ideal" and give high whatever extra is left */ | |
685 | extra_low_div = ideal_low_div - min_low_div; | |
e26747bf DW |
686 | t_calc->div_low = ideal_low_div; |
687 | t_calc->div_high = min_high_div + (extra_div - extra_low_div); | |
0285f8f5 | 688 | } |
689 | ||
690 | /* | |
249051f4 MS |
691 | * Adjust to the fact that the hardware has an implicit "+1". |
692 | * NOTE: Above calculations always produce div_low > 0 and div_high > 0. | |
693 | */ | |
e26747bf DW |
694 | t_calc->div_low--; |
695 | t_calc->div_high--; | |
0285f8f5 | 696 | |
399c168a DW |
697 | /* Give the tuning value 0, that would not update con register */ |
698 | t_calc->tuning = 0; | |
249051f4 | 699 | /* Maximum divider supported by hw is 0xffff */ |
e26747bf DW |
700 | if (t_calc->div_low > 0xffff) { |
701 | t_calc->div_low = 0xffff; | |
249051f4 MS |
702 | ret = -EINVAL; |
703 | } | |
704 | ||
e26747bf DW |
705 | if (t_calc->div_high > 0xffff) { |
706 | t_calc->div_high = 0xffff; | |
249051f4 MS |
707 | ret = -EINVAL; |
708 | } | |
709 | ||
710 | return ret; | |
0285f8f5 | 711 | } |
712 | ||
7e086c3f DW |
713 | /** |
714 | * Calculate timing values for desired SCL frequency | |
715 | * | |
716 | * @clk_rate: I2C input clock rate | |
717 | * @t: Known I2C timing information | |
718 | * @t_calc: Caculated rk3x private timings that would be written into regs | |
719 | * | |
720 | * Returns: 0 on success, -EINVAL if the goal SCL rate is too slow. In that case | |
721 | * a best-effort divider value is returned in divs. If the target rate is | |
722 | * too high, we silently use the highest possible rate. | |
723 | * The following formulas are v1's method to calculate timings. | |
724 | * | |
725 | * l = divl + 1; | |
726 | * h = divh + 1; | |
727 | * s = sda_update_config + 1; | |
728 | * u = start_setup_config + 1; | |
729 | * p = stop_setup_config + 1; | |
730 | * T = Tclk_i2c; | |
731 | * | |
732 | * tHigh = 8 * h * T; | |
733 | * tLow = 8 * l * T; | |
734 | * | |
735 | * tHD;sda = (l * s + 1) * T; | |
736 | * tSU;sda = [(8 - s) * l + 1] * T; | |
737 | * tI2C = 8 * (l + h) * T; | |
738 | * | |
739 | * tSU;sta = (8h * u + 1) * T; | |
740 | * tHD;sta = [8h * (u + 1) - 1] * T; | |
741 | * tSU;sto = (8h * p + 1) * T; | |
742 | */ | |
743 | static int rk3x_i2c_v1_calc_timings(unsigned long clk_rate, | |
744 | struct i2c_timings *t, | |
745 | struct rk3x_i2c_calced_timings *t_calc) | |
746 | { | |
72cf8c56 | 747 | unsigned long min_low_ns, min_high_ns; |
7e086c3f DW |
748 | unsigned long min_setup_start_ns, min_setup_data_ns; |
749 | unsigned long min_setup_stop_ns, max_hold_data_ns; | |
750 | ||
751 | unsigned long clk_rate_khz, scl_rate_khz; | |
752 | ||
753 | unsigned long min_low_div, min_high_div; | |
754 | ||
755 | unsigned long min_div_for_hold, min_total_div; | |
756 | unsigned long extra_div, extra_low_div; | |
757 | unsigned long sda_update_cfg, stp_sta_cfg, stp_sto_cfg; | |
758 | ||
759 | const struct i2c_spec_values *spec; | |
760 | int ret = 0; | |
761 | ||
a02f3d08 DW |
762 | /* Support standard-mode, fast-mode and fast-mode plus */ |
763 | if (WARN_ON(t->bus_freq_hz > 1000000)) | |
764 | t->bus_freq_hz = 1000000; | |
7e086c3f DW |
765 | |
766 | /* prevent scl_rate_khz from becoming 0 */ | |
767 | if (WARN_ON(t->bus_freq_hz < 1000)) | |
768 | t->bus_freq_hz = 1000; | |
769 | ||
770 | /* | |
771 | * min_low_ns: The minimum number of ns we need to hold low to | |
772 | * meet I2C specification, should include fall time. | |
773 | * min_high_ns: The minimum number of ns we need to hold high to | |
774 | * meet I2C specification, should include rise time. | |
775 | */ | |
776 | spec = rk3x_i2c_get_spec(t->bus_freq_hz); | |
777 | ||
778 | /* calculate min-divh and min-divl */ | |
779 | clk_rate_khz = DIV_ROUND_UP(clk_rate, 1000); | |
780 | scl_rate_khz = t->bus_freq_hz / 1000; | |
781 | min_total_div = DIV_ROUND_UP(clk_rate_khz, scl_rate_khz * 8); | |
782 | ||
783 | min_high_ns = t->scl_rise_ns + spec->min_high_ns; | |
784 | min_high_div = DIV_ROUND_UP(clk_rate_khz * min_high_ns, 8 * 1000000); | |
785 | ||
786 | min_low_ns = t->scl_fall_ns + spec->min_low_ns; | |
787 | min_low_div = DIV_ROUND_UP(clk_rate_khz * min_low_ns, 8 * 1000000); | |
788 | ||
789 | /* | |
790 | * Final divh and divl must be greater than 0, otherwise the | |
791 | * hardware would not output the i2c clk. | |
792 | */ | |
793 | min_high_div = (min_high_div < 1) ? 2 : min_high_div; | |
794 | min_low_div = (min_low_div < 1) ? 2 : min_low_div; | |
795 | ||
796 | /* These are the min dividers needed for min hold times. */ | |
797 | min_div_for_hold = (min_low_div + min_high_div); | |
7e086c3f DW |
798 | |
799 | /* | |
800 | * This is the maximum divider so we don't go over the maximum. | |
801 | * We don't round up here (we round down) since this is a maximum. | |
802 | */ | |
803 | if (min_div_for_hold >= min_total_div) { | |
804 | /* | |
805 | * Time needed to meet hold requirements is important. | |
806 | * Just use that. | |
807 | */ | |
808 | t_calc->div_low = min_low_div; | |
809 | t_calc->div_high = min_high_div; | |
810 | } else { | |
811 | /* | |
812 | * We've got to distribute some time among the low and high | |
813 | * so we don't run too fast. | |
814 | * We'll try to split things up by the scale of min_low_div and | |
815 | * min_high_div, biasing slightly towards having a higher div | |
816 | * for low (spend more time low). | |
817 | */ | |
818 | extra_div = min_total_div - min_div_for_hold; | |
819 | extra_low_div = DIV_ROUND_UP(min_low_div * extra_div, | |
820 | min_div_for_hold); | |
821 | ||
822 | t_calc->div_low = min_low_div + extra_low_div; | |
823 | t_calc->div_high = min_high_div + (extra_div - extra_low_div); | |
824 | } | |
825 | ||
826 | /* | |
827 | * calculate sda data hold count by the rules, data_upd_st:3 | |
828 | * is a appropriate value to reduce calculated times. | |
829 | */ | |
830 | for (sda_update_cfg = 3; sda_update_cfg > 0; sda_update_cfg--) { | |
831 | max_hold_data_ns = DIV_ROUND_UP((sda_update_cfg | |
832 | * (t_calc->div_low) + 1) | |
833 | * 1000000, clk_rate_khz); | |
834 | min_setup_data_ns = DIV_ROUND_UP(((8 - sda_update_cfg) | |
835 | * (t_calc->div_low) + 1) | |
836 | * 1000000, clk_rate_khz); | |
837 | if ((max_hold_data_ns < spec->max_data_hold_ns) && | |
838 | (min_setup_data_ns > spec->min_data_setup_ns)) | |
839 | break; | |
840 | } | |
841 | ||
842 | /* calculate setup start config */ | |
843 | min_setup_start_ns = t->scl_rise_ns + spec->min_setup_start_ns; | |
844 | stp_sta_cfg = DIV_ROUND_UP(clk_rate_khz * min_setup_start_ns | |
845 | - 1000000, 8 * 1000000 * (t_calc->div_high)); | |
846 | ||
847 | /* calculate setup stop config */ | |
848 | min_setup_stop_ns = t->scl_rise_ns + spec->min_setup_stop_ns; | |
849 | stp_sto_cfg = DIV_ROUND_UP(clk_rate_khz * min_setup_stop_ns | |
850 | - 1000000, 8 * 1000000 * (t_calc->div_high)); | |
851 | ||
852 | t_calc->tuning = REG_CON_SDA_CFG(--sda_update_cfg) | | |
853 | REG_CON_STA_CFG(--stp_sta_cfg) | | |
854 | REG_CON_STO_CFG(--stp_sto_cfg); | |
855 | ||
856 | t_calc->div_low--; | |
857 | t_calc->div_high--; | |
858 | ||
859 | /* Maximum divider supported by hw is 0xffff */ | |
860 | if (t_calc->div_low > 0xffff) { | |
861 | t_calc->div_low = 0xffff; | |
862 | ret = -EINVAL; | |
863 | } | |
864 | ||
865 | if (t_calc->div_high > 0xffff) { | |
866 | t_calc->div_high = 0xffff; | |
867 | ret = -EINVAL; | |
868 | } | |
869 | ||
870 | return ret; | |
871 | } | |
872 | ||
249051f4 | 873 | static void rk3x_i2c_adapt_div(struct rk3x_i2c *i2c, unsigned long clk_rate) |
0285f8f5 | 874 | { |
1ab92956 | 875 | struct i2c_timings *t = &i2c->t; |
e26747bf | 876 | struct rk3x_i2c_calced_timings calc; |
0285f8f5 | 877 | u64 t_low_ns, t_high_ns; |
7e086c3f DW |
878 | unsigned long flags; |
879 | u32 val; | |
249051f4 | 880 | int ret; |
0285f8f5 | 881 | |
7e086c3f | 882 | ret = i2c->soc_data->calc_timings(clk_rate, t, &calc); |
1ab92956 | 883 | WARN_ONCE(ret != 0, "Could not reach SCL freq %u", t->bus_freq_hz); |
249051f4 | 884 | |
7e086c3f DW |
885 | clk_enable(i2c->pclk); |
886 | ||
887 | spin_lock_irqsave(&i2c->lock, flags); | |
888 | val = i2c_readl(i2c, REG_CON); | |
889 | val &= ~REG_CON_TUNING_MASK; | |
890 | val |= calc.tuning; | |
891 | i2c_writel(i2c, val, REG_CON); | |
e26747bf DW |
892 | i2c_writel(i2c, (calc.div_high << 16) | (calc.div_low & 0xffff), |
893 | REG_CLKDIV); | |
7e086c3f DW |
894 | spin_unlock_irqrestore(&i2c->lock, flags); |
895 | ||
896 | clk_disable(i2c->pclk); | |
0285f8f5 | 897 | |
e26747bf DW |
898 | t_low_ns = div_u64(((u64)calc.div_low + 1) * 8 * 1000000000, clk_rate); |
899 | t_high_ns = div_u64(((u64)calc.div_high + 1) * 8 * 1000000000, | |
900 | clk_rate); | |
0285f8f5 | 901 | dev_dbg(i2c->dev, |
249051f4 MS |
902 | "CLK %lukhz, Req %uns, Act low %lluns high %lluns\n", |
903 | clk_rate / 1000, | |
1ab92956 | 904 | 1000000000 / t->bus_freq_hz, |
0285f8f5 | 905 | t_low_ns, t_high_ns); |
249051f4 | 906 | } |
0285f8f5 | 907 | |
249051f4 MS |
908 | /** |
909 | * rk3x_i2c_clk_notifier_cb - Clock rate change callback | |
910 | * @nb: Pointer to notifier block | |
911 | * @event: Notification reason | |
912 | * @data: Pointer to notification data object | |
913 | * | |
914 | * The callback checks whether a valid bus frequency can be generated after the | |
915 | * change. If so, the change is acknowledged, otherwise the change is aborted. | |
916 | * New dividers are written to the HW in the pre- or post change notification | |
917 | * depending on the scaling direction. | |
918 | * | |
919 | * Code adapted from i2c-cadence.c. | |
920 | * | |
921 | * Return: NOTIFY_STOP if the rate change should be aborted, NOTIFY_OK | |
e0603c8d | 922 | * to acknowledge the change, NOTIFY_DONE if the notification is |
249051f4 MS |
923 | * considered irrelevant. |
924 | */ | |
925 | static int rk3x_i2c_clk_notifier_cb(struct notifier_block *nb, unsigned long | |
926 | event, void *data) | |
927 | { | |
928 | struct clk_notifier_data *ndata = data; | |
929 | struct rk3x_i2c *i2c = container_of(nb, struct rk3x_i2c, clk_rate_nb); | |
e26747bf | 930 | struct rk3x_i2c_calced_timings calc; |
249051f4 MS |
931 | |
932 | switch (event) { | |
933 | case PRE_RATE_CHANGE: | |
7e086c3f DW |
934 | /* |
935 | * Try the calculation (but don't store the result) ahead of | |
936 | * time to see if we need to block the clock change. Timings | |
937 | * shouldn't actually take effect until rk3x_i2c_adapt_div(). | |
938 | */ | |
939 | if (i2c->soc_data->calc_timings(ndata->new_rate, &i2c->t, | |
940 | &calc) != 0) | |
249051f4 | 941 | return NOTIFY_STOP; |
249051f4 MS |
942 | |
943 | /* scale up */ | |
944 | if (ndata->new_rate > ndata->old_rate) | |
945 | rk3x_i2c_adapt_div(i2c, ndata->new_rate); | |
946 | ||
947 | return NOTIFY_OK; | |
948 | case POST_RATE_CHANGE: | |
949 | /* scale down */ | |
950 | if (ndata->new_rate < ndata->old_rate) | |
951 | rk3x_i2c_adapt_div(i2c, ndata->new_rate); | |
952 | return NOTIFY_OK; | |
953 | case ABORT_RATE_CHANGE: | |
954 | /* scale up */ | |
955 | if (ndata->new_rate > ndata->old_rate) | |
956 | rk3x_i2c_adapt_div(i2c, ndata->old_rate); | |
957 | return NOTIFY_OK; | |
958 | default: | |
959 | return NOTIFY_DONE; | |
960 | } | |
c41aa3ce MS |
961 | } |
962 | ||
963 | /** | |
964 | * Setup I2C registers for an I2C operation specified by msgs, num. | |
965 | * | |
966 | * Must be called with i2c->lock held. | |
967 | * | |
968 | * @msgs: I2C msgs to process | |
969 | * @num: Number of msgs | |
970 | * | |
971 | * returns: Number of I2C msgs processed or negative in case of error | |
972 | */ | |
973 | static int rk3x_i2c_setup(struct rk3x_i2c *i2c, struct i2c_msg *msgs, int num) | |
974 | { | |
975 | u32 addr = (msgs[0].addr & 0x7f) << 1; | |
976 | int ret = 0; | |
977 | ||
978 | /* | |
979 | * The I2C adapter can issue a small (len < 4) write packet before | |
980 | * reading. This speeds up SMBus-style register reads. | |
981 | * The MRXADDR/MRXRADDR hold the slave address and the slave register | |
982 | * address in this case. | |
983 | */ | |
984 | ||
985 | if (num >= 2 && msgs[0].len < 4 && | |
986 | !(msgs[0].flags & I2C_M_RD) && (msgs[1].flags & I2C_M_RD)) { | |
987 | u32 reg_addr = 0; | |
988 | int i; | |
989 | ||
990 | dev_dbg(i2c->dev, "Combined write/read from addr 0x%x\n", | |
991 | addr >> 1); | |
992 | ||
993 | /* Fill MRXRADDR with the register address(es) */ | |
994 | for (i = 0; i < msgs[0].len; ++i) { | |
995 | reg_addr |= msgs[0].buf[i] << (i * 8); | |
996 | reg_addr |= REG_MRXADDR_VALID(i); | |
997 | } | |
998 | ||
999 | /* msgs[0] is handled by hw. */ | |
1000 | i2c->msg = &msgs[1]; | |
1001 | ||
1002 | i2c->mode = REG_CON_MOD_REGISTER_TX; | |
1003 | ||
1004 | i2c_writel(i2c, addr | REG_MRXADDR_VALID(0), REG_MRXADDR); | |
1005 | i2c_writel(i2c, reg_addr, REG_MRXRADDR); | |
1006 | ||
1007 | ret = 2; | |
1008 | } else { | |
1009 | /* | |
1010 | * We'll have to do it the boring way and process the msgs | |
1011 | * one-by-one. | |
1012 | */ | |
1013 | ||
1014 | if (msgs[0].flags & I2C_M_RD) { | |
1015 | addr |= 1; /* set read bit */ | |
1016 | ||
1017 | /* | |
1018 | * We have to transmit the slave addr first. Use | |
1019 | * MOD_REGISTER_TX for that purpose. | |
1020 | */ | |
1021 | i2c->mode = REG_CON_MOD_REGISTER_TX; | |
1022 | i2c_writel(i2c, addr | REG_MRXADDR_VALID(0), | |
1023 | REG_MRXADDR); | |
1024 | i2c_writel(i2c, 0, REG_MRXRADDR); | |
1025 | } else { | |
1026 | i2c->mode = REG_CON_MOD_TX; | |
1027 | } | |
1028 | ||
1029 | i2c->msg = &msgs[0]; | |
1030 | ||
1031 | ret = 1; | |
1032 | } | |
1033 | ||
1034 | i2c->addr = msgs[0].addr; | |
1035 | i2c->busy = true; | |
1036 | i2c->state = STATE_START; | |
1037 | i2c->processed = 0; | |
1038 | i2c->error = 0; | |
1039 | ||
1040 | rk3x_i2c_clean_ipd(i2c); | |
1041 | ||
1042 | return ret; | |
1043 | } | |
1044 | ||
1045 | static int rk3x_i2c_xfer(struct i2c_adapter *adap, | |
1046 | struct i2c_msg *msgs, int num) | |
1047 | { | |
1048 | struct rk3x_i2c *i2c = (struct rk3x_i2c *)adap->algo_data; | |
1049 | unsigned long timeout, flags; | |
7e086c3f | 1050 | u32 val; |
c41aa3ce MS |
1051 | int ret = 0; |
1052 | int i; | |
1053 | ||
1054 | spin_lock_irqsave(&i2c->lock, flags); | |
1055 | ||
1056 | clk_enable(i2c->clk); | |
7e086c3f | 1057 | clk_enable(i2c->pclk); |
c41aa3ce | 1058 | |
c41aa3ce MS |
1059 | i2c->is_last_msg = false; |
1060 | ||
1061 | /* | |
1062 | * Process msgs. We can handle more than one message at once (see | |
1063 | * rk3x_i2c_setup()). | |
1064 | */ | |
1065 | for (i = 0; i < num; i += ret) { | |
1066 | ret = rk3x_i2c_setup(i2c, msgs + i, num - i); | |
1067 | ||
1068 | if (ret < 0) { | |
1069 | dev_err(i2c->dev, "rk3x_i2c_setup() failed\n"); | |
1070 | break; | |
1071 | } | |
1072 | ||
1073 | if (i + ret >= num) | |
1074 | i2c->is_last_msg = true; | |
1075 | ||
1076 | spin_unlock_irqrestore(&i2c->lock, flags); | |
1077 | ||
1078 | rk3x_i2c_start(i2c); | |
1079 | ||
1080 | timeout = wait_event_timeout(i2c->wait, !i2c->busy, | |
1081 | msecs_to_jiffies(WAIT_TIMEOUT)); | |
1082 | ||
1083 | spin_lock_irqsave(&i2c->lock, flags); | |
1084 | ||
1085 | if (timeout == 0) { | |
1086 | dev_err(i2c->dev, "timeout, ipd: 0x%02x, state: %d\n", | |
1087 | i2c_readl(i2c, REG_IPD), i2c->state); | |
1088 | ||
1089 | /* Force a STOP condition without interrupt */ | |
1090 | i2c_writel(i2c, 0, REG_IEN); | |
7e086c3f DW |
1091 | val = i2c_readl(i2c, REG_CON) & REG_CON_TUNING_MASK; |
1092 | val |= REG_CON_EN | REG_CON_STOP; | |
1093 | i2c_writel(i2c, val, REG_CON); | |
c41aa3ce MS |
1094 | |
1095 | i2c->state = STATE_IDLE; | |
1096 | ||
1097 | ret = -ETIMEDOUT; | |
1098 | break; | |
1099 | } | |
1100 | ||
1101 | if (i2c->error) { | |
1102 | ret = i2c->error; | |
1103 | break; | |
1104 | } | |
1105 | } | |
1106 | ||
7e086c3f | 1107 | clk_disable(i2c->pclk); |
c41aa3ce | 1108 | clk_disable(i2c->clk); |
7e086c3f | 1109 | |
c41aa3ce MS |
1110 | spin_unlock_irqrestore(&i2c->lock, flags); |
1111 | ||
c6cbfb91 | 1112 | return ret < 0 ? ret : num; |
c41aa3ce MS |
1113 | } |
1114 | ||
cbfff439 DA |
1115 | static __maybe_unused int rk3x_i2c_resume(struct device *dev) |
1116 | { | |
1117 | struct rk3x_i2c *i2c = dev_get_drvdata(dev); | |
1118 | ||
1119 | rk3x_i2c_adapt_div(i2c, clk_get_rate(i2c->clk)); | |
1120 | ||
1121 | return 0; | |
1122 | } | |
1123 | ||
c41aa3ce MS |
1124 | static u32 rk3x_i2c_func(struct i2c_adapter *adap) |
1125 | { | |
1126 | return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_PROTOCOL_MANGLING; | |
1127 | } | |
1128 | ||
1129 | static const struct i2c_algorithm rk3x_i2c_algorithm = { | |
1130 | .master_xfer = rk3x_i2c_xfer, | |
1131 | .functionality = rk3x_i2c_func, | |
1132 | }; | |
1133 | ||
0dbb9634 AY |
1134 | static const struct rk3x_i2c_soc_data rv1108_soc_data = { |
1135 | .grf_offset = -1, | |
1136 | .calc_timings = rk3x_i2c_v1_calc_timings, | |
1137 | }; | |
1138 | ||
bef358c4 DW |
1139 | static const struct rk3x_i2c_soc_data rk3066_soc_data = { |
1140 | .grf_offset = 0x154, | |
7e086c3f | 1141 | .calc_timings = rk3x_i2c_v0_calc_timings, |
bef358c4 DW |
1142 | }; |
1143 | ||
1144 | static const struct rk3x_i2c_soc_data rk3188_soc_data = { | |
1145 | .grf_offset = 0x0a4, | |
7e086c3f | 1146 | .calc_timings = rk3x_i2c_v0_calc_timings, |
bef358c4 DW |
1147 | }; |
1148 | ||
1149 | static const struct rk3x_i2c_soc_data rk3228_soc_data = { | |
1150 | .grf_offset = -1, | |
7e086c3f | 1151 | .calc_timings = rk3x_i2c_v0_calc_timings, |
bef358c4 DW |
1152 | }; |
1153 | ||
1154 | static const struct rk3x_i2c_soc_data rk3288_soc_data = { | |
1155 | .grf_offset = -1, | |
7e086c3f DW |
1156 | .calc_timings = rk3x_i2c_v0_calc_timings, |
1157 | }; | |
1158 | ||
1159 | static const struct rk3x_i2c_soc_data rk3399_soc_data = { | |
1160 | .grf_offset = -1, | |
1161 | .calc_timings = rk3x_i2c_v1_calc_timings, | |
c41aa3ce MS |
1162 | }; |
1163 | ||
1164 | static const struct of_device_id rk3x_i2c_match[] = { | |
0dbb9634 AY |
1165 | { |
1166 | .compatible = "rockchip,rv1108-i2c", | |
1167 | .data = (void *)&rv1108_soc_data | |
1168 | }, | |
bef358c4 DW |
1169 | { |
1170 | .compatible = "rockchip,rk3066-i2c", | |
1171 | .data = (void *)&rk3066_soc_data | |
1172 | }, | |
1173 | { | |
1174 | .compatible = "rockchip,rk3188-i2c", | |
1175 | .data = (void *)&rk3188_soc_data | |
1176 | }, | |
1177 | { | |
1178 | .compatible = "rockchip,rk3228-i2c", | |
1179 | .data = (void *)&rk3228_soc_data | |
1180 | }, | |
1181 | { | |
1182 | .compatible = "rockchip,rk3288-i2c", | |
1183 | .data = (void *)&rk3288_soc_data | |
1184 | }, | |
7e086c3f DW |
1185 | { |
1186 | .compatible = "rockchip,rk3399-i2c", | |
1187 | .data = (void *)&rk3399_soc_data | |
1188 | }, | |
c51bd6ac | 1189 | {}, |
c41aa3ce | 1190 | }; |
598cf161 | 1191 | MODULE_DEVICE_TABLE(of, rk3x_i2c_match); |
c41aa3ce MS |
1192 | |
1193 | static int rk3x_i2c_probe(struct platform_device *pdev) | |
1194 | { | |
1195 | struct device_node *np = pdev->dev.of_node; | |
1196 | const struct of_device_id *match; | |
1197 | struct rk3x_i2c *i2c; | |
1198 | struct resource *mem; | |
1199 | int ret = 0; | |
1200 | int bus_nr; | |
1201 | u32 value; | |
1202 | int irq; | |
249051f4 | 1203 | unsigned long clk_rate; |
c41aa3ce MS |
1204 | |
1205 | i2c = devm_kzalloc(&pdev->dev, sizeof(struct rk3x_i2c), GFP_KERNEL); | |
1206 | if (!i2c) | |
1207 | return -ENOMEM; | |
1208 | ||
1209 | match = of_match_node(rk3x_i2c_match, np); | |
1210 | i2c->soc_data = (struct rk3x_i2c_soc_data *)match->data; | |
1211 | ||
1ab92956 DW |
1212 | /* use common interface to get I2C timing properties */ |
1213 | i2c_parse_fw_timings(&pdev->dev, &i2c->t, true); | |
1330e291 | 1214 | |
c41aa3ce MS |
1215 | strlcpy(i2c->adap.name, "rk3x-i2c", sizeof(i2c->adap.name)); |
1216 | i2c->adap.owner = THIS_MODULE; | |
1217 | i2c->adap.algo = &rk3x_i2c_algorithm; | |
1218 | i2c->adap.retries = 3; | |
1219 | i2c->adap.dev.of_node = np; | |
1220 | i2c->adap.algo_data = i2c; | |
1221 | i2c->adap.dev.parent = &pdev->dev; | |
1222 | ||
1223 | i2c->dev = &pdev->dev; | |
1224 | ||
1225 | spin_lock_init(&i2c->lock); | |
1226 | init_waitqueue_head(&i2c->wait); | |
1227 | ||
c41aa3ce MS |
1228 | mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
1229 | i2c->regs = devm_ioremap_resource(&pdev->dev, mem); | |
1230 | if (IS_ERR(i2c->regs)) | |
1231 | return PTR_ERR(i2c->regs); | |
1232 | ||
1233 | /* Try to set the I2C adapter number from dt */ | |
1234 | bus_nr = of_alias_get_id(np, "i2c"); | |
1235 | ||
1236 | /* | |
1237 | * Switch to new interface if the SoC also offers the old one. | |
1238 | * The control bit is located in the GRF register space. | |
1239 | */ | |
1240 | if (i2c->soc_data->grf_offset >= 0) { | |
1241 | struct regmap *grf; | |
1242 | ||
1243 | grf = syscon_regmap_lookup_by_phandle(np, "rockchip,grf"); | |
1244 | if (IS_ERR(grf)) { | |
1245 | dev_err(&pdev->dev, | |
1246 | "rk3x-i2c needs 'rockchip,grf' property\n"); | |
1247 | return PTR_ERR(grf); | |
1248 | } | |
1249 | ||
1250 | if (bus_nr < 0) { | |
1251 | dev_err(&pdev->dev, "rk3x-i2c needs i2cX alias"); | |
1252 | return -EINVAL; | |
1253 | } | |
1254 | ||
1255 | /* 27+i: write mask, 11+i: value */ | |
1256 | value = BIT(27 + bus_nr) | BIT(11 + bus_nr); | |
1257 | ||
1258 | ret = regmap_write(grf, i2c->soc_data->grf_offset, value); | |
1259 | if (ret != 0) { | |
1260 | dev_err(i2c->dev, "Could not write to GRF: %d\n", ret); | |
1261 | return ret; | |
1262 | } | |
1263 | } | |
1264 | ||
1265 | /* IRQ setup */ | |
1266 | irq = platform_get_irq(pdev, 0); | |
1267 | if (irq < 0) { | |
1268 | dev_err(&pdev->dev, "cannot find rk3x IRQ\n"); | |
1269 | return irq; | |
1270 | } | |
1271 | ||
1272 | ret = devm_request_irq(&pdev->dev, irq, rk3x_i2c_irq, | |
1273 | 0, dev_name(&pdev->dev), i2c); | |
1274 | if (ret < 0) { | |
1275 | dev_err(&pdev->dev, "cannot request IRQ\n"); | |
1276 | return ret; | |
1277 | } | |
1278 | ||
1279 | platform_set_drvdata(pdev, i2c); | |
1280 | ||
7e086c3f DW |
1281 | if (i2c->soc_data->calc_timings == rk3x_i2c_v0_calc_timings) { |
1282 | /* Only one clock to use for bus clock and peripheral clock */ | |
1283 | i2c->clk = devm_clk_get(&pdev->dev, NULL); | |
1284 | i2c->pclk = i2c->clk; | |
1285 | } else { | |
1286 | i2c->clk = devm_clk_get(&pdev->dev, "i2c"); | |
1287 | i2c->pclk = devm_clk_get(&pdev->dev, "pclk"); | |
1288 | } | |
1289 | ||
1290 | if (IS_ERR(i2c->clk)) { | |
1291 | ret = PTR_ERR(i2c->clk); | |
1292 | if (ret != -EPROBE_DEFER) | |
1293 | dev_err(&pdev->dev, "Can't get bus clk: %d\n", ret); | |
1294 | return ret; | |
1295 | } | |
1296 | if (IS_ERR(i2c->pclk)) { | |
1297 | ret = PTR_ERR(i2c->pclk); | |
1298 | if (ret != -EPROBE_DEFER) | |
1299 | dev_err(&pdev->dev, "Can't get periph clk: %d\n", ret); | |
1300 | return ret; | |
1301 | } | |
1302 | ||
c41aa3ce MS |
1303 | ret = clk_prepare(i2c->clk); |
1304 | if (ret < 0) { | |
7e086c3f | 1305 | dev_err(&pdev->dev, "Can't prepare bus clk: %d\n", ret); |
c41aa3ce MS |
1306 | return ret; |
1307 | } | |
7e086c3f DW |
1308 | ret = clk_prepare(i2c->pclk); |
1309 | if (ret < 0) { | |
1310 | dev_err(&pdev->dev, "Can't prepare periph clock: %d\n", ret); | |
1311 | goto err_clk; | |
1312 | } | |
c41aa3ce | 1313 | |
249051f4 MS |
1314 | i2c->clk_rate_nb.notifier_call = rk3x_i2c_clk_notifier_cb; |
1315 | ret = clk_notifier_register(i2c->clk, &i2c->clk_rate_nb); | |
1316 | if (ret != 0) { | |
1317 | dev_err(&pdev->dev, "Unable to register clock notifier\n"); | |
7e086c3f | 1318 | goto err_pclk; |
249051f4 MS |
1319 | } |
1320 | ||
1321 | clk_rate = clk_get_rate(i2c->clk); | |
1322 | rk3x_i2c_adapt_div(i2c, clk_rate); | |
1323 | ||
c41aa3ce | 1324 | ret = i2c_add_adapter(&i2c->adap); |
ea734404 | 1325 | if (ret < 0) |
249051f4 | 1326 | goto err_clk_notifier; |
c41aa3ce MS |
1327 | |
1328 | dev_info(&pdev->dev, "Initialized RK3xxx I2C bus at %p\n", i2c->regs); | |
1329 | ||
1330 | return 0; | |
1331 | ||
249051f4 MS |
1332 | err_clk_notifier: |
1333 | clk_notifier_unregister(i2c->clk, &i2c->clk_rate_nb); | |
7e086c3f DW |
1334 | err_pclk: |
1335 | clk_unprepare(i2c->pclk); | |
c41aa3ce MS |
1336 | err_clk: |
1337 | clk_unprepare(i2c->clk); | |
1338 | return ret; | |
1339 | } | |
1340 | ||
1341 | static int rk3x_i2c_remove(struct platform_device *pdev) | |
1342 | { | |
1343 | struct rk3x_i2c *i2c = platform_get_drvdata(pdev); | |
1344 | ||
1345 | i2c_del_adapter(&i2c->adap); | |
249051f4 MS |
1346 | |
1347 | clk_notifier_unregister(i2c->clk, &i2c->clk_rate_nb); | |
7e086c3f | 1348 | clk_unprepare(i2c->pclk); |
c41aa3ce MS |
1349 | clk_unprepare(i2c->clk); |
1350 | ||
1351 | return 0; | |
1352 | } | |
1353 | ||
cbfff439 DA |
1354 | static SIMPLE_DEV_PM_OPS(rk3x_i2c_pm_ops, NULL, rk3x_i2c_resume); |
1355 | ||
c41aa3ce MS |
1356 | static struct platform_driver rk3x_i2c_driver = { |
1357 | .probe = rk3x_i2c_probe, | |
1358 | .remove = rk3x_i2c_remove, | |
1359 | .driver = { | |
c41aa3ce MS |
1360 | .name = "rk3x-i2c", |
1361 | .of_match_table = rk3x_i2c_match, | |
cbfff439 | 1362 | .pm = &rk3x_i2c_pm_ops, |
c41aa3ce MS |
1363 | }, |
1364 | }; | |
1365 | ||
1366 | module_platform_driver(rk3x_i2c_driver); | |
1367 | ||
1368 | MODULE_DESCRIPTION("Rockchip RK3xxx I2C Bus driver"); | |
1369 | MODULE_AUTHOR("Max Schwarz <max.schwarz@online.de>"); | |
1370 | MODULE_LICENSE("GPL v2"); |