Commit | Line | Data |
---|---|---|
d2912cb1 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
c41aa3ce MS |
2 | /* |
3 | * Driver for I2C adapter in Rockchip RK3xxx SoC | |
4 | * | |
5 | * Max Schwarz <max.schwarz@online.de> | |
6 | * based on the patches by Rockchip Inc. | |
c41aa3ce MS |
7 | */ |
8 | ||
9 | #include <linux/kernel.h> | |
10 | #include <linux/module.h> | |
11 | #include <linux/i2c.h> | |
12 | #include <linux/interrupt.h> | |
f3e2bd71 | 13 | #include <linux/iopoll.h> |
c41aa3ce MS |
14 | #include <linux/errno.h> |
15 | #include <linux/err.h> | |
16 | #include <linux/platform_device.h> | |
17 | #include <linux/io.h> | |
18 | #include <linux/of_address.h> | |
19 | #include <linux/of_irq.h> | |
20 | #include <linux/spinlock.h> | |
21 | #include <linux/clk.h> | |
22 | #include <linux/wait.h> | |
23 | #include <linux/mfd/syscon.h> | |
24 | #include <linux/regmap.h> | |
0285f8f5 | 25 | #include <linux/math64.h> |
c41aa3ce MS |
26 | |
27 | ||
28 | /* Register Map */ | |
29 | #define REG_CON 0x00 /* control register */ | |
30 | #define REG_CLKDIV 0x04 /* clock divisor register */ | |
b340db73 WS |
31 | #define REG_MRXADDR 0x08 /* target address for REGISTER_TX */ |
32 | #define REG_MRXRADDR 0x0c /* target register address for REGISTER_TX */ | |
c41aa3ce MS |
33 | #define REG_MTXCNT 0x10 /* number of bytes to be transmitted */ |
34 | #define REG_MRXCNT 0x14 /* number of bytes to be received */ | |
35 | #define REG_IEN 0x18 /* interrupt enable */ | |
36 | #define REG_IPD 0x1c /* interrupt pending */ | |
37 | #define REG_FCNT 0x20 /* finished count */ | |
38 | ||
39 | /* Data buffer offsets */ | |
40 | #define TXBUFFER_BASE 0x100 | |
41 | #define RXBUFFER_BASE 0x200 | |
42 | ||
43 | /* REG_CON bits */ | |
44 | #define REG_CON_EN BIT(0) | |
45 | enum { | |
46 | REG_CON_MOD_TX = 0, /* transmit data */ | |
47 | REG_CON_MOD_REGISTER_TX, /* select register and restart */ | |
48 | REG_CON_MOD_RX, /* receive data */ | |
49 | REG_CON_MOD_REGISTER_RX, /* broken: transmits read addr AND writes | |
50 | * register addr */ | |
51 | }; | |
52 | #define REG_CON_MOD(mod) ((mod) << 1) | |
53 | #define REG_CON_MOD_MASK (BIT(1) | BIT(2)) | |
54 | #define REG_CON_START BIT(3) | |
55 | #define REG_CON_STOP BIT(4) | |
56 | #define REG_CON_LASTACK BIT(5) /* 1: send NACK after last received byte */ | |
57 | #define REG_CON_ACTACK BIT(6) /* 1: stop if NACK is received */ | |
58 | ||
a8a7d09e | 59 | #define REG_CON_TUNING_MASK GENMASK_ULL(15, 8) |
7e086c3f DW |
60 | |
61 | #define REG_CON_SDA_CFG(cfg) ((cfg) << 8) | |
62 | #define REG_CON_STA_CFG(cfg) ((cfg) << 12) | |
63 | #define REG_CON_STO_CFG(cfg) ((cfg) << 14) | |
64 | ||
c41aa3ce MS |
65 | /* REG_MRXADDR bits */ |
66 | #define REG_MRXADDR_VALID(x) BIT(24 + (x)) /* [x*8+7:x*8] of MRX[R]ADDR valid */ | |
67 | ||
68 | /* REG_IEN/REG_IPD bits */ | |
69 | #define REG_INT_BTF BIT(0) /* a byte was transmitted */ | |
70 | #define REG_INT_BRF BIT(1) /* a byte was received */ | |
b340db73 WS |
71 | #define REG_INT_MBTF BIT(2) /* controller data transmit finished */ |
72 | #define REG_INT_MBRF BIT(3) /* controller data receive finished */ | |
c41aa3ce MS |
73 | #define REG_INT_START BIT(4) /* START condition generated */ |
74 | #define REG_INT_STOP BIT(5) /* STOP condition generated */ | |
75 | #define REG_INT_NAKRCV BIT(6) /* NACK received */ | |
76 | #define REG_INT_ALL 0x7f | |
77 | ||
78 | /* Constants */ | |
4489750f | 79 | #define WAIT_TIMEOUT 1000 /* ms */ |
c41aa3ce MS |
80 | #define DEFAULT_SCL_RATE (100 * 1000) /* Hz */ |
81 | ||
b58fd3be | 82 | /** |
0582d984 | 83 | * struct i2c_spec_values - I2C specification values for various modes |
7e086c3f | 84 | * @min_hold_start_ns: min hold time (repeated) START condition |
b58fd3be DW |
85 | * @min_low_ns: min LOW period of the SCL clock |
86 | * @min_high_ns: min HIGH period of the SCL cloc | |
87 | * @min_setup_start_ns: min set-up time for a repeated START conditio | |
88 | * @max_data_hold_ns: max data hold time | |
7e086c3f DW |
89 | * @min_data_setup_ns: min data set-up time |
90 | * @min_setup_stop_ns: min set-up time for STOP condition | |
91 | * @min_hold_buffer_ns: min bus free time between a STOP and | |
92 | * START condition | |
b58fd3be DW |
93 | */ |
94 | struct i2c_spec_values { | |
7e086c3f | 95 | unsigned long min_hold_start_ns; |
b58fd3be DW |
96 | unsigned long min_low_ns; |
97 | unsigned long min_high_ns; | |
98 | unsigned long min_setup_start_ns; | |
99 | unsigned long max_data_hold_ns; | |
7e086c3f DW |
100 | unsigned long min_data_setup_ns; |
101 | unsigned long min_setup_stop_ns; | |
102 | unsigned long min_hold_buffer_ns; | |
b58fd3be DW |
103 | }; |
104 | ||
105 | static const struct i2c_spec_values standard_mode_spec = { | |
7e086c3f | 106 | .min_hold_start_ns = 4000, |
b58fd3be DW |
107 | .min_low_ns = 4700, |
108 | .min_high_ns = 4000, | |
109 | .min_setup_start_ns = 4700, | |
110 | .max_data_hold_ns = 3450, | |
7e086c3f DW |
111 | .min_data_setup_ns = 250, |
112 | .min_setup_stop_ns = 4000, | |
113 | .min_hold_buffer_ns = 4700, | |
b58fd3be DW |
114 | }; |
115 | ||
116 | static const struct i2c_spec_values fast_mode_spec = { | |
7e086c3f | 117 | .min_hold_start_ns = 600, |
b58fd3be DW |
118 | .min_low_ns = 1300, |
119 | .min_high_ns = 600, | |
120 | .min_setup_start_ns = 600, | |
121 | .max_data_hold_ns = 900, | |
7e086c3f DW |
122 | .min_data_setup_ns = 100, |
123 | .min_setup_stop_ns = 600, | |
124 | .min_hold_buffer_ns = 1300, | |
b58fd3be DW |
125 | }; |
126 | ||
a02f3d08 DW |
127 | static const struct i2c_spec_values fast_mode_plus_spec = { |
128 | .min_hold_start_ns = 260, | |
129 | .min_low_ns = 500, | |
130 | .min_high_ns = 260, | |
131 | .min_setup_start_ns = 260, | |
132 | .max_data_hold_ns = 400, | |
133 | .min_data_setup_ns = 50, | |
134 | .min_setup_stop_ns = 260, | |
135 | .min_hold_buffer_ns = 500, | |
136 | }; | |
137 | ||
e26747bf | 138 | /** |
0582d984 | 139 | * struct rk3x_i2c_calced_timings - calculated V1 timings |
e26747bf DW |
140 | * @div_low: Divider output for low |
141 | * @div_high: Divider output for high | |
7e086c3f DW |
142 | * @tuning: Used to adjust setup/hold data time, |
143 | * setup/hold start time and setup stop time for | |
144 | * v1's calc_timings, the tuning should all be 0 | |
145 | * for old hardware anyone using v0's calc_timings. | |
e26747bf DW |
146 | */ |
147 | struct rk3x_i2c_calced_timings { | |
148 | unsigned long div_low; | |
149 | unsigned long div_high; | |
7e086c3f | 150 | unsigned int tuning; |
e26747bf DW |
151 | }; |
152 | ||
c41aa3ce MS |
153 | enum rk3x_i2c_state { |
154 | STATE_IDLE, | |
155 | STATE_START, | |
156 | STATE_READ, | |
157 | STATE_WRITE, | |
158 | STATE_STOP | |
159 | }; | |
160 | ||
161 | /** | |
0582d984 | 162 | * struct rk3x_i2c_soc_data - SOC-specific data |
c41aa3ce | 163 | * @grf_offset: offset inside the grf regmap for setting the i2c type |
7e086c3f | 164 | * @calc_timings: Callback function for i2c timing information calculated |
c41aa3ce MS |
165 | */ |
166 | struct rk3x_i2c_soc_data { | |
167 | int grf_offset; | |
7e086c3f DW |
168 | int (*calc_timings)(unsigned long, struct i2c_timings *, |
169 | struct rk3x_i2c_calced_timings *); | |
c41aa3ce MS |
170 | }; |
171 | ||
0a6ad2f9 DW |
172 | /** |
173 | * struct rk3x_i2c - private data of the controller | |
174 | * @adap: corresponding I2C adapter | |
175 | * @dev: device for this controller | |
176 | * @soc_data: related soc data struct | |
177 | * @regs: virtual memory area | |
7e086c3f DW |
178 | * @clk: function clk for rk3399 or function & Bus clks for others |
179 | * @pclk: Bus clk for rk3399 | |
0a6ad2f9 | 180 | * @clk_rate_nb: i2c clk rate change notify |
19cde9c9 | 181 | * @irq: irq number |
0a6ad2f9 DW |
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 | |
b340db73 | 187 | * @addr: addr of i2c target device |
0a6ad2f9 DW |
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; | |
d032a2eb | 197 | const struct rk3x_i2c_soc_data *soc_data; |
c41aa3ce MS |
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; |
19cde9c9 | 204 | int irq; |
c41aa3ce MS |
205 | |
206 | /* Settings */ | |
1ab92956 | 207 | struct i2c_timings t; |
c41aa3ce MS |
208 | |
209 | /* Synchronization & notification */ | |
210 | spinlock_t lock; | |
211 | wait_queue_head_t wait; | |
212 | bool busy; | |
213 | ||
214 | /* Current message */ | |
215 | struct i2c_msg *msg; | |
216 | u8 addr; | |
217 | unsigned int mode; | |
218 | bool is_last_msg; | |
219 | ||
220 | /* I2C state machine */ | |
221 | enum rk3x_i2c_state state; | |
0a6ad2f9 | 222 | unsigned int processed; |
c41aa3ce MS |
223 | int error; |
224 | }; | |
225 | ||
226 | static inline void i2c_writel(struct rk3x_i2c *i2c, u32 value, | |
227 | unsigned int offset) | |
228 | { | |
229 | writel(value, i2c->regs + offset); | |
230 | } | |
231 | ||
232 | static inline u32 i2c_readl(struct rk3x_i2c *i2c, unsigned int offset) | |
233 | { | |
234 | return readl(i2c->regs + offset); | |
235 | } | |
236 | ||
237 | /* Reset all interrupt pending bits */ | |
238 | static inline void rk3x_i2c_clean_ipd(struct rk3x_i2c *i2c) | |
239 | { | |
240 | i2c_writel(i2c, REG_INT_ALL, REG_IPD); | |
241 | } | |
242 | ||
243 | /** | |
0582d984 RD |
244 | * rk3x_i2c_start - Generate a START condition, which triggers a REG_INT_START interrupt. |
245 | * @i2c: target controller data | |
c41aa3ce MS |
246 | */ |
247 | static void rk3x_i2c_start(struct rk3x_i2c *i2c) | |
248 | { | |
7e086c3f | 249 | u32 val = i2c_readl(i2c, REG_CON) & REG_CON_TUNING_MASK; |
c41aa3ce | 250 | |
c41aa3ce MS |
251 | i2c_writel(i2c, REG_INT_START, REG_IEN); |
252 | ||
253 | /* enable adapter with correct mode, send START condition */ | |
7e086c3f | 254 | val |= REG_CON_EN | REG_CON_MOD(i2c->mode) | REG_CON_START; |
c41aa3ce MS |
255 | |
256 | /* if we want to react to NACK, set ACTACK bit */ | |
257 | if (!(i2c->msg->flags & I2C_M_IGNORE_NAK)) | |
258 | val |= REG_CON_ACTACK; | |
259 | ||
260 | i2c_writel(i2c, val, REG_CON); | |
261 | } | |
262 | ||
263 | /** | |
0582d984 RD |
264 | * rk3x_i2c_stop - Generate a STOP condition, which triggers a REG_INT_STOP interrupt. |
265 | * @i2c: target controller data | |
c41aa3ce MS |
266 | * @error: Error code to return in rk3x_i2c_xfer |
267 | */ | |
268 | static void rk3x_i2c_stop(struct rk3x_i2c *i2c, int error) | |
269 | { | |
270 | unsigned int ctrl; | |
271 | ||
272 | i2c->processed = 0; | |
273 | i2c->msg = NULL; | |
274 | i2c->error = error; | |
275 | ||
276 | if (i2c->is_last_msg) { | |
277 | /* Enable stop interrupt */ | |
278 | i2c_writel(i2c, REG_INT_STOP, REG_IEN); | |
279 | ||
280 | i2c->state = STATE_STOP; | |
281 | ||
282 | ctrl = i2c_readl(i2c, REG_CON); | |
283 | ctrl |= REG_CON_STOP; | |
284 | i2c_writel(i2c, ctrl, REG_CON); | |
285 | } else { | |
286 | /* Signal rk3x_i2c_xfer to start the next message. */ | |
287 | i2c->busy = false; | |
288 | i2c->state = STATE_IDLE; | |
289 | ||
290 | /* | |
291 | * The HW is actually not capable of REPEATED START. But we can | |
292 | * get the intended effect by resetting its internal state | |
293 | * and issuing an ordinary START. | |
294 | */ | |
7e086c3f DW |
295 | ctrl = i2c_readl(i2c, REG_CON) & REG_CON_TUNING_MASK; |
296 | i2c_writel(i2c, ctrl, REG_CON); | |
c41aa3ce MS |
297 | |
298 | /* signal that we are finished with the current msg */ | |
299 | wake_up(&i2c->wait); | |
300 | } | |
301 | } | |
302 | ||
303 | /** | |
0582d984 RD |
304 | * rk3x_i2c_prepare_read - Setup a read according to i2c->msg |
305 | * @i2c: target controller data | |
c41aa3ce MS |
306 | */ |
307 | static void rk3x_i2c_prepare_read(struct rk3x_i2c *i2c) | |
308 | { | |
309 | unsigned int len = i2c->msg->len - i2c->processed; | |
310 | u32 con; | |
311 | ||
312 | con = i2c_readl(i2c, REG_CON); | |
313 | ||
314 | /* | |
315 | * The hw can read up to 32 bytes at a time. If we need more than one | |
316 | * chunk, send an ACK after the last byte of the current chunk. | |
317 | */ | |
29209338 | 318 | if (len > 32) { |
c41aa3ce MS |
319 | len = 32; |
320 | con &= ~REG_CON_LASTACK; | |
321 | } else { | |
322 | con |= REG_CON_LASTACK; | |
323 | } | |
324 | ||
325 | /* make sure we are in plain RX mode if we read a second chunk */ | |
326 | if (i2c->processed != 0) { | |
327 | con &= ~REG_CON_MOD_MASK; | |
328 | con |= REG_CON_MOD(REG_CON_MOD_RX); | |
329 | } | |
330 | ||
331 | i2c_writel(i2c, con, REG_CON); | |
332 | i2c_writel(i2c, len, REG_MRXCNT); | |
333 | } | |
334 | ||
335 | /** | |
0582d984 RD |
336 | * rk3x_i2c_fill_transmit_buf - Fill the transmit buffer with data from i2c->msg |
337 | * @i2c: target controller data | |
c41aa3ce MS |
338 | */ |
339 | static void rk3x_i2c_fill_transmit_buf(struct rk3x_i2c *i2c) | |
340 | { | |
341 | unsigned int i, j; | |
342 | u32 cnt = 0; | |
343 | u32 val; | |
344 | u8 byte; | |
345 | ||
346 | for (i = 0; i < 8; ++i) { | |
347 | val = 0; | |
348 | for (j = 0; j < 4; ++j) { | |
cf27020d | 349 | if ((i2c->processed == i2c->msg->len) && (cnt != 0)) |
c41aa3ce MS |
350 | break; |
351 | ||
352 | if (i2c->processed == 0 && cnt == 0) | |
353 | byte = (i2c->addr & 0x7f) << 1; | |
354 | else | |
355 | byte = i2c->msg->buf[i2c->processed++]; | |
356 | ||
357 | val |= byte << (j * 8); | |
358 | cnt++; | |
359 | } | |
360 | ||
361 | i2c_writel(i2c, val, TXBUFFER_BASE + 4 * i); | |
362 | ||
363 | if (i2c->processed == i2c->msg->len) | |
364 | break; | |
365 | } | |
366 | ||
367 | i2c_writel(i2c, cnt, REG_MTXCNT); | |
368 | } | |
369 | ||
370 | ||
371 | /* IRQ handlers for individual states */ | |
372 | ||
373 | static void rk3x_i2c_handle_start(struct rk3x_i2c *i2c, unsigned int ipd) | |
374 | { | |
375 | if (!(ipd & REG_INT_START)) { | |
376 | rk3x_i2c_stop(i2c, -EIO); | |
377 | dev_warn(i2c->dev, "unexpected irq in START: 0x%x\n", ipd); | |
378 | rk3x_i2c_clean_ipd(i2c); | |
379 | return; | |
380 | } | |
381 | ||
382 | /* ack interrupt */ | |
383 | i2c_writel(i2c, REG_INT_START, REG_IPD); | |
384 | ||
385 | /* disable start bit */ | |
386 | i2c_writel(i2c, i2c_readl(i2c, REG_CON) & ~REG_CON_START, REG_CON); | |
387 | ||
388 | /* enable appropriate interrupts and transition */ | |
389 | if (i2c->mode == REG_CON_MOD_TX) { | |
390 | i2c_writel(i2c, REG_INT_MBTF | REG_INT_NAKRCV, REG_IEN); | |
391 | i2c->state = STATE_WRITE; | |
392 | rk3x_i2c_fill_transmit_buf(i2c); | |
393 | } else { | |
394 | /* in any other case, we are going to be reading. */ | |
395 | i2c_writel(i2c, REG_INT_MBRF | REG_INT_NAKRCV, REG_IEN); | |
396 | i2c->state = STATE_READ; | |
397 | rk3x_i2c_prepare_read(i2c); | |
398 | } | |
399 | } | |
400 | ||
401 | static void rk3x_i2c_handle_write(struct rk3x_i2c *i2c, unsigned int ipd) | |
402 | { | |
403 | if (!(ipd & REG_INT_MBTF)) { | |
404 | rk3x_i2c_stop(i2c, -EIO); | |
405 | dev_err(i2c->dev, "unexpected irq in WRITE: 0x%x\n", ipd); | |
406 | rk3x_i2c_clean_ipd(i2c); | |
407 | return; | |
408 | } | |
409 | ||
410 | /* ack interrupt */ | |
411 | i2c_writel(i2c, REG_INT_MBTF, REG_IPD); | |
412 | ||
413 | /* are we finished? */ | |
414 | if (i2c->processed == i2c->msg->len) | |
415 | rk3x_i2c_stop(i2c, i2c->error); | |
416 | else | |
417 | rk3x_i2c_fill_transmit_buf(i2c); | |
418 | } | |
419 | ||
420 | static void rk3x_i2c_handle_read(struct rk3x_i2c *i2c, unsigned int ipd) | |
421 | { | |
422 | unsigned int i; | |
423 | unsigned int len = i2c->msg->len - i2c->processed; | |
3f649ab7 | 424 | u32 val; |
c41aa3ce MS |
425 | u8 byte; |
426 | ||
427 | /* we only care for MBRF here. */ | |
428 | if (!(ipd & REG_INT_MBRF)) | |
429 | return; | |
430 | ||
02fe0fbd OJ |
431 | /* ack interrupt (read also produces a spurious START flag, clear it too) */ |
432 | i2c_writel(i2c, REG_INT_MBRF | REG_INT_START, REG_IPD); | |
c41aa3ce | 433 | |
5da4309f | 434 | /* Can only handle a maximum of 32 bytes at a time */ |
435 | if (len > 32) | |
436 | len = 32; | |
437 | ||
c41aa3ce MS |
438 | /* read the data from receive buffer */ |
439 | for (i = 0; i < len; ++i) { | |
440 | if (i % 4 == 0) | |
441 | val = i2c_readl(i2c, RXBUFFER_BASE + (i / 4) * 4); | |
442 | ||
443 | byte = (val >> ((i % 4) * 8)) & 0xff; | |
444 | i2c->msg->buf[i2c->processed++] = byte; | |
445 | } | |
446 | ||
447 | /* are we finished? */ | |
448 | if (i2c->processed == i2c->msg->len) | |
449 | rk3x_i2c_stop(i2c, i2c->error); | |
450 | else | |
451 | rk3x_i2c_prepare_read(i2c); | |
452 | } | |
453 | ||
454 | static void rk3x_i2c_handle_stop(struct rk3x_i2c *i2c, unsigned int ipd) | |
455 | { | |
456 | unsigned int con; | |
457 | ||
458 | if (!(ipd & REG_INT_STOP)) { | |
459 | rk3x_i2c_stop(i2c, -EIO); | |
460 | dev_err(i2c->dev, "unexpected irq in STOP: 0x%x\n", ipd); | |
461 | rk3x_i2c_clean_ipd(i2c); | |
462 | return; | |
463 | } | |
464 | ||
465 | /* ack interrupt */ | |
466 | i2c_writel(i2c, REG_INT_STOP, REG_IPD); | |
467 | ||
468 | /* disable STOP bit */ | |
469 | con = i2c_readl(i2c, REG_CON); | |
470 | con &= ~REG_CON_STOP; | |
471 | i2c_writel(i2c, con, REG_CON); | |
472 | ||
473 | i2c->busy = false; | |
474 | i2c->state = STATE_IDLE; | |
475 | ||
476 | /* signal rk3x_i2c_xfer that we are finished */ | |
477 | wake_up(&i2c->wait); | |
478 | } | |
479 | ||
480 | static irqreturn_t rk3x_i2c_irq(int irqno, void *dev_id) | |
481 | { | |
482 | struct rk3x_i2c *i2c = dev_id; | |
483 | unsigned int ipd; | |
484 | ||
485 | spin_lock(&i2c->lock); | |
486 | ||
487 | ipd = i2c_readl(i2c, REG_IPD); | |
488 | if (i2c->state == STATE_IDLE) { | |
489 | dev_warn(i2c->dev, "irq in STATE_IDLE, ipd = 0x%x\n", ipd); | |
490 | rk3x_i2c_clean_ipd(i2c); | |
491 | goto out; | |
492 | } | |
493 | ||
494 | dev_dbg(i2c->dev, "IRQ: state %d, ipd: %x\n", i2c->state, ipd); | |
495 | ||
496 | /* Clean interrupt bits we don't care about */ | |
497 | ipd &= ~(REG_INT_BRF | REG_INT_BTF); | |
498 | ||
499 | if (ipd & REG_INT_NAKRCV) { | |
500 | /* | |
501 | * We got a NACK in the last operation. Depending on whether | |
502 | * IGNORE_NAK is set, we have to stop the operation and report | |
503 | * an error. | |
504 | */ | |
505 | i2c_writel(i2c, REG_INT_NAKRCV, REG_IPD); | |
506 | ||
507 | ipd &= ~REG_INT_NAKRCV; | |
508 | ||
509 | if (!(i2c->msg->flags & I2C_M_IGNORE_NAK)) | |
510 | rk3x_i2c_stop(i2c, -ENXIO); | |
511 | } | |
512 | ||
513 | /* is there anything left to handle? */ | |
29209338 | 514 | if ((ipd & REG_INT_ALL) == 0) |
c41aa3ce MS |
515 | goto out; |
516 | ||
517 | switch (i2c->state) { | |
518 | case STATE_START: | |
519 | rk3x_i2c_handle_start(i2c, ipd); | |
520 | break; | |
521 | case STATE_WRITE: | |
522 | rk3x_i2c_handle_write(i2c, ipd); | |
523 | break; | |
524 | case STATE_READ: | |
525 | rk3x_i2c_handle_read(i2c, ipd); | |
526 | break; | |
527 | case STATE_STOP: | |
528 | rk3x_i2c_handle_stop(i2c, ipd); | |
529 | break; | |
530 | case STATE_IDLE: | |
531 | break; | |
532 | } | |
533 | ||
534 | out: | |
535 | spin_unlock(&i2c->lock); | |
536 | return IRQ_HANDLED; | |
537 | } | |
538 | ||
b58fd3be | 539 | /** |
0582d984 | 540 | * rk3x_i2c_get_spec - Get timing values of I2C specification |
b58fd3be DW |
541 | * @speed: Desired SCL frequency |
542 | * | |
0582d984 | 543 | * Return: Matched i2c_spec_values. |
b58fd3be DW |
544 | */ |
545 | static const struct i2c_spec_values *rk3x_i2c_get_spec(unsigned int speed) | |
546 | { | |
90224e64 | 547 | if (speed <= I2C_MAX_STANDARD_MODE_FREQ) |
b58fd3be | 548 | return &standard_mode_spec; |
90224e64 | 549 | else if (speed <= I2C_MAX_FAST_MODE_FREQ) |
b58fd3be | 550 | return &fast_mode_spec; |
a02f3d08 DW |
551 | else |
552 | return &fast_mode_plus_spec; | |
b58fd3be DW |
553 | } |
554 | ||
249051f4 | 555 | /** |
0582d984 | 556 | * rk3x_i2c_v0_calc_timings - Calculate divider values for desired SCL frequency |
249051f4 | 557 | * @clk_rate: I2C input clock rate |
e26747bf DW |
558 | * @t: Known I2C timing information |
559 | * @t_calc: Caculated rk3x private timings that would be written into regs | |
249051f4 | 560 | * |
0582d984 | 561 | * Return: %0 on success, -%EINVAL if the goal SCL rate is too slow. In that case |
249051f4 MS |
562 | * a best-effort divider value is returned in divs. If the target rate is |
563 | * too high, we silently use the highest possible rate. | |
564 | */ | |
7e086c3f DW |
565 | static int rk3x_i2c_v0_calc_timings(unsigned long clk_rate, |
566 | struct i2c_timings *t, | |
567 | struct rk3x_i2c_calced_timings *t_calc) | |
c41aa3ce | 568 | { |
1330e291 | 569 | unsigned long min_low_ns, min_high_ns; |
0285f8f5 | 570 | unsigned long max_low_ns, min_total_ns; |
571 | ||
249051f4 | 572 | unsigned long clk_rate_khz, scl_rate_khz; |
0285f8f5 | 573 | |
574 | unsigned long min_low_div, min_high_div; | |
575 | unsigned long max_low_div; | |
576 | ||
577 | unsigned long min_div_for_hold, min_total_div; | |
578 | unsigned long extra_div, extra_low_div, ideal_low_div; | |
579 | ||
b58fd3be DW |
580 | unsigned long data_hold_buffer_ns = 50; |
581 | const struct i2c_spec_values *spec; | |
249051f4 MS |
582 | int ret = 0; |
583 | ||
0285f8f5 | 584 | /* Only support standard-mode and fast-mode */ |
90224e64 AS |
585 | if (WARN_ON(t->bus_freq_hz > I2C_MAX_FAST_MODE_FREQ)) |
586 | t->bus_freq_hz = I2C_MAX_FAST_MODE_FREQ; | |
0285f8f5 | 587 | |
588 | /* prevent scl_rate_khz from becoming 0 */ | |
1ab92956 DW |
589 | if (WARN_ON(t->bus_freq_hz < 1000)) |
590 | t->bus_freq_hz = 1000; | |
c41aa3ce | 591 | |
0285f8f5 | 592 | /* |
1330e291 | 593 | * min_low_ns: The minimum number of ns we need to hold low to |
594 | * meet I2C specification, should include fall time. | |
595 | * min_high_ns: The minimum number of ns we need to hold high to | |
596 | * meet I2C specification, should include rise time. | |
597 | * max_low_ns: The maximum number of ns we can hold low to meet | |
598 | * I2C specification. | |
0285f8f5 | 599 | * |
1330e291 | 600 | * Note: max_low_ns should be (maximum data hold time * 2 - buffer) |
0285f8f5 | 601 | * This is because the i2c host on Rockchip holds the data line |
602 | * for half the low time. | |
b4a7bd7a | 603 | */ |
b58fd3be DW |
604 | spec = rk3x_i2c_get_spec(t->bus_freq_hz); |
605 | min_high_ns = t->scl_rise_ns + spec->min_high_ns; | |
387f0de6 DA |
606 | |
607 | /* | |
608 | * Timings for repeated start: | |
609 | * - controller appears to drop SDA at .875x (7/8) programmed clk high. | |
610 | * - controller appears to keep SCL high for 2x programmed clk high. | |
611 | * | |
612 | * We need to account for those rules in picking our "high" time so | |
613 | * we meet tSU;STA and tHD;STA times. | |
614 | */ | |
b58fd3be DW |
615 | min_high_ns = max(min_high_ns, DIV_ROUND_UP( |
616 | (t->scl_rise_ns + spec->min_setup_start_ns) * 1000, 875)); | |
617 | min_high_ns = max(min_high_ns, DIV_ROUND_UP( | |
618 | (t->scl_rise_ns + spec->min_setup_start_ns + t->sda_fall_ns + | |
619 | spec->min_high_ns), 2)); | |
620 | ||
621 | min_low_ns = t->scl_fall_ns + spec->min_low_ns; | |
622 | max_low_ns = spec->max_data_hold_ns * 2 - data_hold_buffer_ns; | |
0285f8f5 | 623 | min_total_ns = min_low_ns + min_high_ns; |
624 | ||
625 | /* Adjust to avoid overflow */ | |
249051f4 | 626 | clk_rate_khz = DIV_ROUND_UP(clk_rate, 1000); |
1ab92956 | 627 | scl_rate_khz = t->bus_freq_hz / 1000; |
0285f8f5 | 628 | |
629 | /* | |
630 | * We need the total div to be >= this number | |
631 | * so we don't clock too fast. | |
632 | */ | |
249051f4 | 633 | min_total_div = DIV_ROUND_UP(clk_rate_khz, scl_rate_khz * 8); |
0285f8f5 | 634 | |
635 | /* These are the min dividers needed for min hold times. */ | |
249051f4 MS |
636 | min_low_div = DIV_ROUND_UP(clk_rate_khz * min_low_ns, 8 * 1000000); |
637 | min_high_div = DIV_ROUND_UP(clk_rate_khz * min_high_ns, 8 * 1000000); | |
0285f8f5 | 638 | min_div_for_hold = (min_low_div + min_high_div); |
639 | ||
640 | /* | |
1330e291 | 641 | * This is the maximum divider so we don't go over the maximum. |
642 | * We don't round up here (we round down) since this is a maximum. | |
0285f8f5 | 643 | */ |
249051f4 | 644 | max_low_div = clk_rate_khz * max_low_ns / (8 * 1000000); |
0285f8f5 | 645 | |
646 | if (min_low_div > max_low_div) { | |
647 | WARN_ONCE(true, | |
648 | "Conflicting, min_low_div %lu, max_low_div %lu\n", | |
649 | min_low_div, max_low_div); | |
650 | max_low_div = min_low_div; | |
651 | } | |
652 | ||
653 | if (min_div_for_hold > min_total_div) { | |
654 | /* | |
655 | * Time needed to meet hold requirements is important. | |
656 | * Just use that. | |
657 | */ | |
e26747bf DW |
658 | t_calc->div_low = min_low_div; |
659 | t_calc->div_high = min_high_div; | |
0285f8f5 | 660 | } else { |
661 | /* | |
662 | * We've got to distribute some time among the low and high | |
663 | * so we don't run too fast. | |
664 | */ | |
665 | extra_div = min_total_div - min_div_for_hold; | |
666 | ||
667 | /* | |
668 | * We'll try to split things up perfectly evenly, | |
669 | * biasing slightly towards having a higher div | |
670 | * for low (spend more time low). | |
671 | */ | |
249051f4 | 672 | ideal_low_div = DIV_ROUND_UP(clk_rate_khz * min_low_ns, |
0285f8f5 | 673 | scl_rate_khz * 8 * min_total_ns); |
674 | ||
1330e291 | 675 | /* Don't allow it to go over the maximum */ |
0285f8f5 | 676 | if (ideal_low_div > max_low_div) |
677 | ideal_low_div = max_low_div; | |
c41aa3ce | 678 | |
0285f8f5 | 679 | /* |
680 | * Handle when the ideal low div is going to take up | |
681 | * more than we have. | |
682 | */ | |
683 | if (ideal_low_div > min_low_div + extra_div) | |
684 | ideal_low_div = min_low_div + extra_div; | |
685 | ||
686 | /* Give low the "ideal" and give high whatever extra is left */ | |
687 | extra_low_div = ideal_low_div - min_low_div; | |
e26747bf DW |
688 | t_calc->div_low = ideal_low_div; |
689 | t_calc->div_high = min_high_div + (extra_div - extra_low_div); | |
0285f8f5 | 690 | } |
691 | ||
692 | /* | |
249051f4 MS |
693 | * Adjust to the fact that the hardware has an implicit "+1". |
694 | * NOTE: Above calculations always produce div_low > 0 and div_high > 0. | |
695 | */ | |
e26747bf DW |
696 | t_calc->div_low--; |
697 | t_calc->div_high--; | |
0285f8f5 | 698 | |
399c168a DW |
699 | /* Give the tuning value 0, that would not update con register */ |
700 | t_calc->tuning = 0; | |
249051f4 | 701 | /* Maximum divider supported by hw is 0xffff */ |
e26747bf DW |
702 | if (t_calc->div_low > 0xffff) { |
703 | t_calc->div_low = 0xffff; | |
249051f4 MS |
704 | ret = -EINVAL; |
705 | } | |
706 | ||
e26747bf DW |
707 | if (t_calc->div_high > 0xffff) { |
708 | t_calc->div_high = 0xffff; | |
249051f4 MS |
709 | ret = -EINVAL; |
710 | } | |
711 | ||
712 | return ret; | |
0285f8f5 | 713 | } |
714 | ||
7e086c3f | 715 | /** |
0582d984 | 716 | * rk3x_i2c_v1_calc_timings - Calculate timing values for desired SCL frequency |
7e086c3f DW |
717 | * @clk_rate: I2C input clock rate |
718 | * @t: Known I2C timing information | |
719 | * @t_calc: Caculated rk3x private timings that would be written into regs | |
720 | * | |
0582d984 | 721 | * Return: %0 on success, -%EINVAL if the goal SCL rate is too slow. In that case |
7e086c3f DW |
722 | * a best-effort divider value is returned in divs. If the target rate is |
723 | * too high, we silently use the highest possible rate. | |
724 | * The following formulas are v1's method to calculate timings. | |
725 | * | |
726 | * l = divl + 1; | |
727 | * h = divh + 1; | |
728 | * s = sda_update_config + 1; | |
729 | * u = start_setup_config + 1; | |
730 | * p = stop_setup_config + 1; | |
731 | * T = Tclk_i2c; | |
732 | * | |
733 | * tHigh = 8 * h * T; | |
734 | * tLow = 8 * l * T; | |
735 | * | |
736 | * tHD;sda = (l * s + 1) * T; | |
737 | * tSU;sda = [(8 - s) * l + 1] * T; | |
738 | * tI2C = 8 * (l + h) * T; | |
739 | * | |
740 | * tSU;sta = (8h * u + 1) * T; | |
741 | * tHD;sta = [8h * (u + 1) - 1] * T; | |
742 | * tSU;sto = (8h * p + 1) * T; | |
743 | */ | |
744 | static int rk3x_i2c_v1_calc_timings(unsigned long clk_rate, | |
745 | struct i2c_timings *t, | |
746 | struct rk3x_i2c_calced_timings *t_calc) | |
747 | { | |
72cf8c56 | 748 | unsigned long min_low_ns, min_high_ns; |
7e086c3f DW |
749 | unsigned long min_setup_start_ns, min_setup_data_ns; |
750 | unsigned long min_setup_stop_ns, max_hold_data_ns; | |
751 | ||
752 | unsigned long clk_rate_khz, scl_rate_khz; | |
753 | ||
754 | unsigned long min_low_div, min_high_div; | |
755 | ||
756 | unsigned long min_div_for_hold, min_total_div; | |
757 | unsigned long extra_div, extra_low_div; | |
758 | unsigned long sda_update_cfg, stp_sta_cfg, stp_sto_cfg; | |
759 | ||
760 | const struct i2c_spec_values *spec; | |
761 | int ret = 0; | |
762 | ||
a02f3d08 | 763 | /* Support standard-mode, fast-mode and fast-mode plus */ |
90224e64 AS |
764 | if (WARN_ON(t->bus_freq_hz > I2C_MAX_FAST_MODE_PLUS_FREQ)) |
765 | t->bus_freq_hz = I2C_MAX_FAST_MODE_PLUS_FREQ; | |
7e086c3f DW |
766 | |
767 | /* prevent scl_rate_khz from becoming 0 */ | |
768 | if (WARN_ON(t->bus_freq_hz < 1000)) | |
769 | t->bus_freq_hz = 1000; | |
770 | ||
771 | /* | |
772 | * min_low_ns: The minimum number of ns we need to hold low to | |
773 | * meet I2C specification, should include fall time. | |
774 | * min_high_ns: The minimum number of ns we need to hold high to | |
775 | * meet I2C specification, should include rise time. | |
776 | */ | |
777 | spec = rk3x_i2c_get_spec(t->bus_freq_hz); | |
778 | ||
779 | /* calculate min-divh and min-divl */ | |
780 | clk_rate_khz = DIV_ROUND_UP(clk_rate, 1000); | |
781 | scl_rate_khz = t->bus_freq_hz / 1000; | |
782 | min_total_div = DIV_ROUND_UP(clk_rate_khz, scl_rate_khz * 8); | |
783 | ||
784 | min_high_ns = t->scl_rise_ns + spec->min_high_ns; | |
785 | min_high_div = DIV_ROUND_UP(clk_rate_khz * min_high_ns, 8 * 1000000); | |
786 | ||
787 | min_low_ns = t->scl_fall_ns + spec->min_low_ns; | |
788 | min_low_div = DIV_ROUND_UP(clk_rate_khz * min_low_ns, 8 * 1000000); | |
789 | ||
790 | /* | |
791 | * Final divh and divl must be greater than 0, otherwise the | |
792 | * hardware would not output the i2c clk. | |
793 | */ | |
794 | min_high_div = (min_high_div < 1) ? 2 : min_high_div; | |
795 | min_low_div = (min_low_div < 1) ? 2 : min_low_div; | |
796 | ||
797 | /* These are the min dividers needed for min hold times. */ | |
798 | min_div_for_hold = (min_low_div + min_high_div); | |
7e086c3f DW |
799 | |
800 | /* | |
801 | * This is the maximum divider so we don't go over the maximum. | |
802 | * We don't round up here (we round down) since this is a maximum. | |
803 | */ | |
804 | if (min_div_for_hold >= min_total_div) { | |
805 | /* | |
806 | * Time needed to meet hold requirements is important. | |
807 | * Just use that. | |
808 | */ | |
809 | t_calc->div_low = min_low_div; | |
810 | t_calc->div_high = min_high_div; | |
811 | } else { | |
812 | /* | |
813 | * We've got to distribute some time among the low and high | |
814 | * so we don't run too fast. | |
815 | * We'll try to split things up by the scale of min_low_div and | |
816 | * min_high_div, biasing slightly towards having a higher div | |
817 | * for low (spend more time low). | |
818 | */ | |
819 | extra_div = min_total_div - min_div_for_hold; | |
820 | extra_low_div = DIV_ROUND_UP(min_low_div * extra_div, | |
821 | min_div_for_hold); | |
822 | ||
823 | t_calc->div_low = min_low_div + extra_low_div; | |
824 | t_calc->div_high = min_high_div + (extra_div - extra_low_div); | |
825 | } | |
826 | ||
827 | /* | |
828 | * calculate sda data hold count by the rules, data_upd_st:3 | |
829 | * is a appropriate value to reduce calculated times. | |
830 | */ | |
831 | for (sda_update_cfg = 3; sda_update_cfg > 0; sda_update_cfg--) { | |
832 | max_hold_data_ns = DIV_ROUND_UP((sda_update_cfg | |
833 | * (t_calc->div_low) + 1) | |
834 | * 1000000, clk_rate_khz); | |
835 | min_setup_data_ns = DIV_ROUND_UP(((8 - sda_update_cfg) | |
836 | * (t_calc->div_low) + 1) | |
837 | * 1000000, clk_rate_khz); | |
838 | if ((max_hold_data_ns < spec->max_data_hold_ns) && | |
839 | (min_setup_data_ns > spec->min_data_setup_ns)) | |
840 | break; | |
841 | } | |
842 | ||
843 | /* calculate setup start config */ | |
844 | min_setup_start_ns = t->scl_rise_ns + spec->min_setup_start_ns; | |
845 | stp_sta_cfg = DIV_ROUND_UP(clk_rate_khz * min_setup_start_ns | |
846 | - 1000000, 8 * 1000000 * (t_calc->div_high)); | |
847 | ||
848 | /* calculate setup stop config */ | |
849 | min_setup_stop_ns = t->scl_rise_ns + spec->min_setup_stop_ns; | |
850 | stp_sto_cfg = DIV_ROUND_UP(clk_rate_khz * min_setup_stop_ns | |
851 | - 1000000, 8 * 1000000 * (t_calc->div_high)); | |
852 | ||
853 | t_calc->tuning = REG_CON_SDA_CFG(--sda_update_cfg) | | |
854 | REG_CON_STA_CFG(--stp_sta_cfg) | | |
855 | REG_CON_STO_CFG(--stp_sto_cfg); | |
856 | ||
857 | t_calc->div_low--; | |
858 | t_calc->div_high--; | |
859 | ||
860 | /* Maximum divider supported by hw is 0xffff */ | |
861 | if (t_calc->div_low > 0xffff) { | |
862 | t_calc->div_low = 0xffff; | |
863 | ret = -EINVAL; | |
864 | } | |
865 | ||
866 | if (t_calc->div_high > 0xffff) { | |
867 | t_calc->div_high = 0xffff; | |
868 | ret = -EINVAL; | |
869 | } | |
870 | ||
871 | return ret; | |
872 | } | |
873 | ||
249051f4 | 874 | static void rk3x_i2c_adapt_div(struct rk3x_i2c *i2c, unsigned long clk_rate) |
0285f8f5 | 875 | { |
1ab92956 | 876 | struct i2c_timings *t = &i2c->t; |
e26747bf | 877 | struct rk3x_i2c_calced_timings calc; |
0285f8f5 | 878 | u64 t_low_ns, t_high_ns; |
7e086c3f DW |
879 | unsigned long flags; |
880 | u32 val; | |
249051f4 | 881 | int ret; |
0285f8f5 | 882 | |
7e086c3f | 883 | ret = i2c->soc_data->calc_timings(clk_rate, t, &calc); |
1ab92956 | 884 | WARN_ONCE(ret != 0, "Could not reach SCL freq %u", t->bus_freq_hz); |
249051f4 | 885 | |
7e086c3f DW |
886 | clk_enable(i2c->pclk); |
887 | ||
888 | spin_lock_irqsave(&i2c->lock, flags); | |
889 | val = i2c_readl(i2c, REG_CON); | |
890 | val &= ~REG_CON_TUNING_MASK; | |
891 | val |= calc.tuning; | |
892 | i2c_writel(i2c, val, REG_CON); | |
e26747bf DW |
893 | i2c_writel(i2c, (calc.div_high << 16) | (calc.div_low & 0xffff), |
894 | REG_CLKDIV); | |
7e086c3f DW |
895 | spin_unlock_irqrestore(&i2c->lock, flags); |
896 | ||
897 | clk_disable(i2c->pclk); | |
0285f8f5 | 898 | |
e26747bf DW |
899 | t_low_ns = div_u64(((u64)calc.div_low + 1) * 8 * 1000000000, clk_rate); |
900 | t_high_ns = div_u64(((u64)calc.div_high + 1) * 8 * 1000000000, | |
901 | clk_rate); | |
0285f8f5 | 902 | dev_dbg(i2c->dev, |
249051f4 MS |
903 | "CLK %lukhz, Req %uns, Act low %lluns high %lluns\n", |
904 | clk_rate / 1000, | |
1ab92956 | 905 | 1000000000 / t->bus_freq_hz, |
0285f8f5 | 906 | t_low_ns, t_high_ns); |
249051f4 | 907 | } |
0285f8f5 | 908 | |
249051f4 MS |
909 | /** |
910 | * rk3x_i2c_clk_notifier_cb - Clock rate change callback | |
911 | * @nb: Pointer to notifier block | |
912 | * @event: Notification reason | |
913 | * @data: Pointer to notification data object | |
914 | * | |
915 | * The callback checks whether a valid bus frequency can be generated after the | |
916 | * change. If so, the change is acknowledged, otherwise the change is aborted. | |
917 | * New dividers are written to the HW in the pre- or post change notification | |
918 | * depending on the scaling direction. | |
919 | * | |
920 | * Code adapted from i2c-cadence.c. | |
921 | * | |
922 | * Return: NOTIFY_STOP if the rate change should be aborted, NOTIFY_OK | |
e0603c8d | 923 | * to acknowledge the change, NOTIFY_DONE if the notification is |
249051f4 MS |
924 | * considered irrelevant. |
925 | */ | |
926 | static int rk3x_i2c_clk_notifier_cb(struct notifier_block *nb, unsigned long | |
927 | event, void *data) | |
928 | { | |
929 | struct clk_notifier_data *ndata = data; | |
930 | struct rk3x_i2c *i2c = container_of(nb, struct rk3x_i2c, clk_rate_nb); | |
e26747bf | 931 | struct rk3x_i2c_calced_timings calc; |
249051f4 MS |
932 | |
933 | switch (event) { | |
934 | case PRE_RATE_CHANGE: | |
7e086c3f DW |
935 | /* |
936 | * Try the calculation (but don't store the result) ahead of | |
937 | * time to see if we need to block the clock change. Timings | |
938 | * shouldn't actually take effect until rk3x_i2c_adapt_div(). | |
939 | */ | |
940 | if (i2c->soc_data->calc_timings(ndata->new_rate, &i2c->t, | |
941 | &calc) != 0) | |
249051f4 | 942 | return NOTIFY_STOP; |
249051f4 MS |
943 | |
944 | /* scale up */ | |
945 | if (ndata->new_rate > ndata->old_rate) | |
946 | rk3x_i2c_adapt_div(i2c, ndata->new_rate); | |
947 | ||
948 | return NOTIFY_OK; | |
949 | case POST_RATE_CHANGE: | |
950 | /* scale down */ | |
951 | if (ndata->new_rate < ndata->old_rate) | |
952 | rk3x_i2c_adapt_div(i2c, ndata->new_rate); | |
953 | return NOTIFY_OK; | |
954 | case ABORT_RATE_CHANGE: | |
955 | /* scale up */ | |
956 | if (ndata->new_rate > ndata->old_rate) | |
957 | rk3x_i2c_adapt_div(i2c, ndata->old_rate); | |
958 | return NOTIFY_OK; | |
959 | default: | |
960 | return NOTIFY_DONE; | |
961 | } | |
c41aa3ce MS |
962 | } |
963 | ||
964 | /** | |
0582d984 RD |
965 | * rk3x_i2c_setup - Setup I2C registers for an I2C operation specified by msgs, num. |
966 | * @i2c: target controller data | |
c41aa3ce MS |
967 | * @msgs: I2C msgs to process |
968 | * @num: Number of msgs | |
969 | * | |
0582d984 RD |
970 | * Must be called with i2c->lock held. |
971 | * | |
972 | * Return: Number of I2C msgs processed or negative in case of error | |
c41aa3ce MS |
973 | */ |
974 | static int rk3x_i2c_setup(struct rk3x_i2c *i2c, struct i2c_msg *msgs, int num) | |
975 | { | |
976 | u32 addr = (msgs[0].addr & 0x7f) << 1; | |
977 | int ret = 0; | |
978 | ||
979 | /* | |
980 | * The I2C adapter can issue a small (len < 4) write packet before | |
981 | * reading. This speeds up SMBus-style register reads. | |
b340db73 | 982 | * The MRXADDR/MRXRADDR hold the target address and the target register |
c41aa3ce MS |
983 | * address in this case. |
984 | */ | |
985 | ||
986 | if (num >= 2 && msgs[0].len < 4 && | |
987 | !(msgs[0].flags & I2C_M_RD) && (msgs[1].flags & I2C_M_RD)) { | |
988 | u32 reg_addr = 0; | |
989 | int i; | |
990 | ||
991 | dev_dbg(i2c->dev, "Combined write/read from addr 0x%x\n", | |
992 | addr >> 1); | |
993 | ||
994 | /* Fill MRXRADDR with the register address(es) */ | |
995 | for (i = 0; i < msgs[0].len; ++i) { | |
996 | reg_addr |= msgs[0].buf[i] << (i * 8); | |
997 | reg_addr |= REG_MRXADDR_VALID(i); | |
998 | } | |
999 | ||
1000 | /* msgs[0] is handled by hw. */ | |
1001 | i2c->msg = &msgs[1]; | |
1002 | ||
1003 | i2c->mode = REG_CON_MOD_REGISTER_TX; | |
1004 | ||
1005 | i2c_writel(i2c, addr | REG_MRXADDR_VALID(0), REG_MRXADDR); | |
1006 | i2c_writel(i2c, reg_addr, REG_MRXRADDR); | |
1007 | ||
1008 | ret = 2; | |
1009 | } else { | |
1010 | /* | |
1011 | * We'll have to do it the boring way and process the msgs | |
1012 | * one-by-one. | |
1013 | */ | |
1014 | ||
1015 | if (msgs[0].flags & I2C_M_RD) { | |
1016 | addr |= 1; /* set read bit */ | |
1017 | ||
1018 | /* | |
b340db73 | 1019 | * We have to transmit the target addr first. Use |
c41aa3ce MS |
1020 | * MOD_REGISTER_TX for that purpose. |
1021 | */ | |
1022 | i2c->mode = REG_CON_MOD_REGISTER_TX; | |
1023 | i2c_writel(i2c, addr | REG_MRXADDR_VALID(0), | |
1024 | REG_MRXADDR); | |
1025 | i2c_writel(i2c, 0, REG_MRXRADDR); | |
1026 | } else { | |
1027 | i2c->mode = REG_CON_MOD_TX; | |
1028 | } | |
1029 | ||
1030 | i2c->msg = &msgs[0]; | |
1031 | ||
1032 | ret = 1; | |
1033 | } | |
1034 | ||
1035 | i2c->addr = msgs[0].addr; | |
1036 | i2c->busy = true; | |
1037 | i2c->state = STATE_START; | |
1038 | i2c->processed = 0; | |
1039 | i2c->error = 0; | |
1040 | ||
1041 | rk3x_i2c_clean_ipd(i2c); | |
1042 | ||
1043 | return ret; | |
1044 | } | |
1045 | ||
f3e2bd71 JK |
1046 | static int rk3x_i2c_wait_xfer_poll(struct rk3x_i2c *i2c) |
1047 | { | |
1048 | ktime_t timeout = ktime_add_ms(ktime_get(), WAIT_TIMEOUT); | |
1049 | ||
1050 | while (READ_ONCE(i2c->busy) && | |
1051 | ktime_compare(ktime_get(), timeout) < 0) { | |
1052 | udelay(5); | |
1053 | rk3x_i2c_irq(0, i2c); | |
1054 | } | |
1055 | ||
1056 | return !i2c->busy; | |
1057 | } | |
1058 | ||
1059 | static int rk3x_i2c_xfer_common(struct i2c_adapter *adap, | |
1060 | struct i2c_msg *msgs, int num, bool polling) | |
c41aa3ce MS |
1061 | { |
1062 | struct rk3x_i2c *i2c = (struct rk3x_i2c *)adap->algo_data; | |
749de720 WS |
1063 | unsigned long flags; |
1064 | long time_left; | |
7e086c3f | 1065 | u32 val; |
c41aa3ce MS |
1066 | int ret = 0; |
1067 | int i; | |
1068 | ||
1069 | spin_lock_irqsave(&i2c->lock, flags); | |
1070 | ||
1071 | clk_enable(i2c->clk); | |
7e086c3f | 1072 | clk_enable(i2c->pclk); |
c41aa3ce | 1073 | |
c41aa3ce MS |
1074 | i2c->is_last_msg = false; |
1075 | ||
1076 | /* | |
1077 | * Process msgs. We can handle more than one message at once (see | |
1078 | * rk3x_i2c_setup()). | |
1079 | */ | |
1080 | for (i = 0; i < num; i += ret) { | |
1081 | ret = rk3x_i2c_setup(i2c, msgs + i, num - i); | |
1082 | ||
1083 | if (ret < 0) { | |
1084 | dev_err(i2c->dev, "rk3x_i2c_setup() failed\n"); | |
1085 | break; | |
1086 | } | |
1087 | ||
1088 | if (i + ret >= num) | |
1089 | i2c->is_last_msg = true; | |
1090 | ||
1091 | spin_unlock_irqrestore(&i2c->lock, flags); | |
1092 | ||
f3e2bd71 | 1093 | if (!polling) { |
19cde9c9 JH |
1094 | rk3x_i2c_start(i2c); |
1095 | ||
749de720 WS |
1096 | time_left = wait_event_timeout(i2c->wait, !i2c->busy, |
1097 | msecs_to_jiffies(WAIT_TIMEOUT)); | |
f3e2bd71 | 1098 | } else { |
19cde9c9 JH |
1099 | disable_irq(i2c->irq); |
1100 | rk3x_i2c_start(i2c); | |
1101 | ||
749de720 | 1102 | time_left = rk3x_i2c_wait_xfer_poll(i2c); |
19cde9c9 JH |
1103 | |
1104 | enable_irq(i2c->irq); | |
f3e2bd71 | 1105 | } |
c41aa3ce MS |
1106 | |
1107 | spin_lock_irqsave(&i2c->lock, flags); | |
1108 | ||
749de720 | 1109 | if (time_left == 0) { |
c41aa3ce MS |
1110 | /* Force a STOP condition without interrupt */ |
1111 | i2c_writel(i2c, 0, REG_IEN); | |
7e086c3f DW |
1112 | val = i2c_readl(i2c, REG_CON) & REG_CON_TUNING_MASK; |
1113 | val |= REG_CON_EN | REG_CON_STOP; | |
1114 | i2c_writel(i2c, val, REG_CON); | |
c41aa3ce MS |
1115 | |
1116 | i2c->state = STATE_IDLE; | |
1117 | ||
1118 | ret = -ETIMEDOUT; | |
1119 | break; | |
1120 | } | |
1121 | ||
1122 | if (i2c->error) { | |
1123 | ret = i2c->error; | |
1124 | break; | |
1125 | } | |
1126 | } | |
1127 | ||
7e086c3f | 1128 | clk_disable(i2c->pclk); |
c41aa3ce | 1129 | clk_disable(i2c->clk); |
7e086c3f | 1130 | |
c41aa3ce MS |
1131 | spin_unlock_irqrestore(&i2c->lock, flags); |
1132 | ||
c6cbfb91 | 1133 | return ret < 0 ? ret : num; |
c41aa3ce MS |
1134 | } |
1135 | ||
f3e2bd71 JK |
1136 | static int rk3x_i2c_xfer(struct i2c_adapter *adap, |
1137 | struct i2c_msg *msgs, int num) | |
1138 | { | |
1139 | return rk3x_i2c_xfer_common(adap, msgs, num, false); | |
1140 | } | |
1141 | ||
1142 | static int rk3x_i2c_xfer_polling(struct i2c_adapter *adap, | |
1143 | struct i2c_msg *msgs, int num) | |
1144 | { | |
1145 | return rk3x_i2c_xfer_common(adap, msgs, num, true); | |
1146 | } | |
1147 | ||
cbfff439 DA |
1148 | static __maybe_unused int rk3x_i2c_resume(struct device *dev) |
1149 | { | |
1150 | struct rk3x_i2c *i2c = dev_get_drvdata(dev); | |
1151 | ||
1152 | rk3x_i2c_adapt_div(i2c, clk_get_rate(i2c->clk)); | |
1153 | ||
1154 | return 0; | |
1155 | } | |
1156 | ||
c41aa3ce MS |
1157 | static u32 rk3x_i2c_func(struct i2c_adapter *adap) |
1158 | { | |
1159 | return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_PROTOCOL_MANGLING; | |
1160 | } | |
1161 | ||
1162 | static const struct i2c_algorithm rk3x_i2c_algorithm = { | |
b340db73 WS |
1163 | .xfer = rk3x_i2c_xfer, |
1164 | .xfer_atomic = rk3x_i2c_xfer_polling, | |
1165 | .functionality = rk3x_i2c_func, | |
c41aa3ce MS |
1166 | }; |
1167 | ||
0dbb9634 AY |
1168 | static const struct rk3x_i2c_soc_data rv1108_soc_data = { |
1169 | .grf_offset = -1, | |
1170 | .calc_timings = rk3x_i2c_v1_calc_timings, | |
1171 | }; | |
1172 | ||
859d6468 JT |
1173 | static const struct rk3x_i2c_soc_data rv1126_soc_data = { |
1174 | .grf_offset = 0x118, | |
1175 | .calc_timings = rk3x_i2c_v1_calc_timings, | |
1176 | }; | |
1177 | ||
bef358c4 DW |
1178 | static const struct rk3x_i2c_soc_data rk3066_soc_data = { |
1179 | .grf_offset = 0x154, | |
7e086c3f | 1180 | .calc_timings = rk3x_i2c_v0_calc_timings, |
bef358c4 DW |
1181 | }; |
1182 | ||
1183 | static const struct rk3x_i2c_soc_data rk3188_soc_data = { | |
1184 | .grf_offset = 0x0a4, | |
7e086c3f | 1185 | .calc_timings = rk3x_i2c_v0_calc_timings, |
bef358c4 DW |
1186 | }; |
1187 | ||
1188 | static const struct rk3x_i2c_soc_data rk3228_soc_data = { | |
1189 | .grf_offset = -1, | |
7e086c3f | 1190 | .calc_timings = rk3x_i2c_v0_calc_timings, |
bef358c4 DW |
1191 | }; |
1192 | ||
1193 | static const struct rk3x_i2c_soc_data rk3288_soc_data = { | |
1194 | .grf_offset = -1, | |
7e086c3f DW |
1195 | .calc_timings = rk3x_i2c_v0_calc_timings, |
1196 | }; | |
1197 | ||
1198 | static const struct rk3x_i2c_soc_data rk3399_soc_data = { | |
1199 | .grf_offset = -1, | |
1200 | .calc_timings = rk3x_i2c_v1_calc_timings, | |
c41aa3ce MS |
1201 | }; |
1202 | ||
1203 | static const struct of_device_id rk3x_i2c_match[] = { | |
0dbb9634 AY |
1204 | { |
1205 | .compatible = "rockchip,rv1108-i2c", | |
d032a2eb | 1206 | .data = &rv1108_soc_data |
0dbb9634 | 1207 | }, |
859d6468 JT |
1208 | { |
1209 | .compatible = "rockchip,rv1126-i2c", | |
1210 | .data = &rv1126_soc_data | |
1211 | }, | |
bef358c4 DW |
1212 | { |
1213 | .compatible = "rockchip,rk3066-i2c", | |
d032a2eb | 1214 | .data = &rk3066_soc_data |
bef358c4 DW |
1215 | }, |
1216 | { | |
1217 | .compatible = "rockchip,rk3188-i2c", | |
d032a2eb | 1218 | .data = &rk3188_soc_data |
bef358c4 DW |
1219 | }, |
1220 | { | |
1221 | .compatible = "rockchip,rk3228-i2c", | |
d032a2eb | 1222 | .data = &rk3228_soc_data |
bef358c4 DW |
1223 | }, |
1224 | { | |
1225 | .compatible = "rockchip,rk3288-i2c", | |
d032a2eb | 1226 | .data = &rk3288_soc_data |
bef358c4 | 1227 | }, |
7e086c3f DW |
1228 | { |
1229 | .compatible = "rockchip,rk3399-i2c", | |
d032a2eb | 1230 | .data = &rk3399_soc_data |
7e086c3f | 1231 | }, |
c51bd6ac | 1232 | {}, |
c41aa3ce | 1233 | }; |
598cf161 | 1234 | MODULE_DEVICE_TABLE(of, rk3x_i2c_match); |
c41aa3ce MS |
1235 | |
1236 | static int rk3x_i2c_probe(struct platform_device *pdev) | |
1237 | { | |
1238 | struct device_node *np = pdev->dev.of_node; | |
1239 | const struct of_device_id *match; | |
1240 | struct rk3x_i2c *i2c; | |
c41aa3ce MS |
1241 | int ret = 0; |
1242 | int bus_nr; | |
1243 | u32 value; | |
1244 | int irq; | |
249051f4 | 1245 | unsigned long clk_rate; |
c41aa3ce MS |
1246 | |
1247 | i2c = devm_kzalloc(&pdev->dev, sizeof(struct rk3x_i2c), GFP_KERNEL); | |
1248 | if (!i2c) | |
1249 | return -ENOMEM; | |
1250 | ||
1251 | match = of_match_node(rk3x_i2c_match, np); | |
d032a2eb | 1252 | i2c->soc_data = match->data; |
c41aa3ce | 1253 | |
1ab92956 DW |
1254 | /* use common interface to get I2C timing properties */ |
1255 | i2c_parse_fw_timings(&pdev->dev, &i2c->t, true); | |
1330e291 | 1256 | |
ea1558ce | 1257 | strscpy(i2c->adap.name, "rk3x-i2c", sizeof(i2c->adap.name)); |
c41aa3ce MS |
1258 | i2c->adap.owner = THIS_MODULE; |
1259 | i2c->adap.algo = &rk3x_i2c_algorithm; | |
1260 | i2c->adap.retries = 3; | |
1261 | i2c->adap.dev.of_node = np; | |
1262 | i2c->adap.algo_data = i2c; | |
1263 | i2c->adap.dev.parent = &pdev->dev; | |
1264 | ||
1265 | i2c->dev = &pdev->dev; | |
1266 | ||
1267 | spin_lock_init(&i2c->lock); | |
1268 | init_waitqueue_head(&i2c->wait); | |
1269 | ||
e0442d76 | 1270 | i2c->regs = devm_platform_ioremap_resource(pdev, 0); |
c41aa3ce MS |
1271 | if (IS_ERR(i2c->regs)) |
1272 | return PTR_ERR(i2c->regs); | |
1273 | ||
1274 | /* Try to set the I2C adapter number from dt */ | |
1275 | bus_nr = of_alias_get_id(np, "i2c"); | |
1276 | ||
1277 | /* | |
1278 | * Switch to new interface if the SoC also offers the old one. | |
1279 | * The control bit is located in the GRF register space. | |
1280 | */ | |
1281 | if (i2c->soc_data->grf_offset >= 0) { | |
1282 | struct regmap *grf; | |
1283 | ||
1284 | grf = syscon_regmap_lookup_by_phandle(np, "rockchip,grf"); | |
1285 | if (IS_ERR(grf)) { | |
1286 | dev_err(&pdev->dev, | |
1287 | "rk3x-i2c needs 'rockchip,grf' property\n"); | |
1288 | return PTR_ERR(grf); | |
1289 | } | |
1290 | ||
1291 | if (bus_nr < 0) { | |
1292 | dev_err(&pdev->dev, "rk3x-i2c needs i2cX alias"); | |
1293 | return -EINVAL; | |
1294 | } | |
1295 | ||
92a85b7c TL |
1296 | /* rv1126 i2c2 uses non-sequential write mask 20, value 4 */ |
1297 | if (i2c->soc_data == &rv1126_soc_data && bus_nr == 2) | |
1298 | value = BIT(20) | BIT(4); | |
1299 | else | |
1300 | /* 27+i: write mask, 11+i: value */ | |
1301 | value = BIT(27 + bus_nr) | BIT(11 + bus_nr); | |
c41aa3ce MS |
1302 | |
1303 | ret = regmap_write(grf, i2c->soc_data->grf_offset, value); | |
1304 | if (ret != 0) { | |
1305 | dev_err(i2c->dev, "Could not write to GRF: %d\n", ret); | |
1306 | return ret; | |
1307 | } | |
1308 | } | |
1309 | ||
1310 | /* IRQ setup */ | |
1311 | irq = platform_get_irq(pdev, 0); | |
e42688ed | 1312 | if (irq < 0) |
c41aa3ce | 1313 | return irq; |
c41aa3ce MS |
1314 | |
1315 | ret = devm_request_irq(&pdev->dev, irq, rk3x_i2c_irq, | |
1316 | 0, dev_name(&pdev->dev), i2c); | |
1317 | if (ret < 0) { | |
1318 | dev_err(&pdev->dev, "cannot request IRQ\n"); | |
1319 | return ret; | |
1320 | } | |
1321 | ||
19cde9c9 JH |
1322 | i2c->irq = irq; |
1323 | ||
c41aa3ce MS |
1324 | platform_set_drvdata(pdev, i2c); |
1325 | ||
7e086c3f DW |
1326 | if (i2c->soc_data->calc_timings == rk3x_i2c_v0_calc_timings) { |
1327 | /* Only one clock to use for bus clock and peripheral clock */ | |
1328 | i2c->clk = devm_clk_get(&pdev->dev, NULL); | |
1329 | i2c->pclk = i2c->clk; | |
1330 | } else { | |
1331 | i2c->clk = devm_clk_get(&pdev->dev, "i2c"); | |
1332 | i2c->pclk = devm_clk_get(&pdev->dev, "pclk"); | |
1333 | } | |
1334 | ||
91a73027 KK |
1335 | if (IS_ERR(i2c->clk)) |
1336 | return dev_err_probe(&pdev->dev, PTR_ERR(i2c->clk), | |
1337 | "Can't get bus clk\n"); | |
1338 | ||
1339 | if (IS_ERR(i2c->pclk)) | |
1340 | return dev_err_probe(&pdev->dev, PTR_ERR(i2c->pclk), | |
1341 | "Can't get periph clk\n"); | |
7e086c3f | 1342 | |
c41aa3ce MS |
1343 | ret = clk_prepare(i2c->clk); |
1344 | if (ret < 0) { | |
7e086c3f | 1345 | dev_err(&pdev->dev, "Can't prepare bus clk: %d\n", ret); |
c41aa3ce MS |
1346 | return ret; |
1347 | } | |
7e086c3f DW |
1348 | ret = clk_prepare(i2c->pclk); |
1349 | if (ret < 0) { | |
1350 | dev_err(&pdev->dev, "Can't prepare periph clock: %d\n", ret); | |
1351 | goto err_clk; | |
1352 | } | |
c41aa3ce | 1353 | |
249051f4 MS |
1354 | i2c->clk_rate_nb.notifier_call = rk3x_i2c_clk_notifier_cb; |
1355 | ret = clk_notifier_register(i2c->clk, &i2c->clk_rate_nb); | |
1356 | if (ret != 0) { | |
1357 | dev_err(&pdev->dev, "Unable to register clock notifier\n"); | |
7e086c3f | 1358 | goto err_pclk; |
249051f4 MS |
1359 | } |
1360 | ||
b57e9018 JK |
1361 | ret = clk_enable(i2c->clk); |
1362 | if (ret < 0) { | |
1363 | dev_err(&pdev->dev, "Can't enable bus clk: %d\n", ret); | |
1364 | goto err_clk_notifier; | |
1365 | } | |
1366 | ||
249051f4 MS |
1367 | clk_rate = clk_get_rate(i2c->clk); |
1368 | rk3x_i2c_adapt_div(i2c, clk_rate); | |
b57e9018 | 1369 | clk_disable(i2c->clk); |
249051f4 | 1370 | |
c41aa3ce | 1371 | ret = i2c_add_adapter(&i2c->adap); |
ea734404 | 1372 | if (ret < 0) |
249051f4 | 1373 | goto err_clk_notifier; |
c41aa3ce | 1374 | |
c41aa3ce MS |
1375 | return 0; |
1376 | ||
249051f4 MS |
1377 | err_clk_notifier: |
1378 | clk_notifier_unregister(i2c->clk, &i2c->clk_rate_nb); | |
7e086c3f DW |
1379 | err_pclk: |
1380 | clk_unprepare(i2c->pclk); | |
c41aa3ce MS |
1381 | err_clk: |
1382 | clk_unprepare(i2c->clk); | |
1383 | return ret; | |
1384 | } | |
1385 | ||
e190a0c3 | 1386 | static void rk3x_i2c_remove(struct platform_device *pdev) |
c41aa3ce MS |
1387 | { |
1388 | struct rk3x_i2c *i2c = platform_get_drvdata(pdev); | |
1389 | ||
1390 | i2c_del_adapter(&i2c->adap); | |
249051f4 MS |
1391 | |
1392 | clk_notifier_unregister(i2c->clk, &i2c->clk_rate_nb); | |
7e086c3f | 1393 | clk_unprepare(i2c->pclk); |
c41aa3ce | 1394 | clk_unprepare(i2c->clk); |
c41aa3ce MS |
1395 | } |
1396 | ||
cbfff439 DA |
1397 | static SIMPLE_DEV_PM_OPS(rk3x_i2c_pm_ops, NULL, rk3x_i2c_resume); |
1398 | ||
c41aa3ce MS |
1399 | static struct platform_driver rk3x_i2c_driver = { |
1400 | .probe = rk3x_i2c_probe, | |
e190a0c3 | 1401 | .remove_new = rk3x_i2c_remove, |
c41aa3ce | 1402 | .driver = { |
c41aa3ce MS |
1403 | .name = "rk3x-i2c", |
1404 | .of_match_table = rk3x_i2c_match, | |
cbfff439 | 1405 | .pm = &rk3x_i2c_pm_ops, |
c41aa3ce MS |
1406 | }, |
1407 | }; | |
1408 | ||
1409 | module_platform_driver(rk3x_i2c_driver); | |
1410 | ||
1411 | MODULE_DESCRIPTION("Rockchip RK3xxx I2C Bus driver"); | |
1412 | MODULE_AUTHOR("Max Schwarz <max.schwarz@online.de>"); | |
1413 | MODULE_LICENSE("GPL v2"); |