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d7a131d3 | 1 | // SPDX-License-Identifier: GPL-2.0 |
7edf7369 BG |
2 | /* |
3 | * Copyright (C) STMicroelectronics 2016 | |
4 | * | |
5 | * Author: Gerald Baeza <gerald.baeza@st.com> | |
6 | * | |
7edf7369 BG |
7 | * Inspired by timer-stm32.c from Maxime Coquelin |
8 | * pwm-atmel.c from Bo Shen | |
9 | */ | |
10 | ||
ab3a8978 | 11 | #include <linux/bitfield.h> |
7edf7369 BG |
12 | #include <linux/mfd/stm32-timers.h> |
13 | #include <linux/module.h> | |
14 | #include <linux/of.h> | |
2d3aa06b | 15 | #include <linux/pinctrl/consumer.h> |
7edf7369 BG |
16 | #include <linux/platform_device.h> |
17 | #include <linux/pwm.h> | |
18 | ||
19 | #define CCMR_CHANNEL_SHIFT 8 | |
20 | #define CCMR_CHANNEL_MASK 0xFF | |
21 | #define MAX_BREAKINPUT 2 | |
22 | ||
0f9d2ecb FG |
23 | struct stm32_breakinput { |
24 | u32 index; | |
25 | u32 level; | |
26 | u32 filter; | |
27 | }; | |
28 | ||
7edf7369 | 29 | struct stm32_pwm { |
4eb67a20 | 30 | struct mutex lock; /* protect pwm config/enable */ |
7edf7369 BG |
31 | struct clk *clk; |
32 | struct regmap *regmap; | |
33 | u32 max_arr; | |
34 | bool have_complementary_output; | |
0f9d2ecb FG |
35 | struct stm32_breakinput breakinputs[MAX_BREAKINPUT]; |
36 | unsigned int num_breakinputs; | |
53e38fe7 | 37 | u32 capture[4] ____cacheline_aligned; /* DMA'able buffer */ |
7edf7369 BG |
38 | }; |
39 | ||
7edf7369 BG |
40 | static inline struct stm32_pwm *to_stm32_pwm_dev(struct pwm_chip *chip) |
41 | { | |
174821b7 | 42 | return pwmchip_get_drvdata(chip); |
7edf7369 BG |
43 | } |
44 | ||
45 | static u32 active_channels(struct stm32_pwm *dev) | |
46 | { | |
47 | u32 ccer; | |
48 | ||
49 | regmap_read(dev->regmap, TIM_CCER, &ccer); | |
50 | ||
51 | return ccer & TIM_CCER_CCXE; | |
52 | } | |
53 | ||
53e38fe7 FG |
54 | #define TIM_CCER_CC12P (TIM_CCER_CC1P | TIM_CCER_CC2P) |
55 | #define TIM_CCER_CC12E (TIM_CCER_CC1E | TIM_CCER_CC2E) | |
56 | #define TIM_CCER_CC34P (TIM_CCER_CC3P | TIM_CCER_CC4P) | |
57 | #define TIM_CCER_CC34E (TIM_CCER_CC3E | TIM_CCER_CC4E) | |
58 | ||
59 | /* | |
60 | * Capture using PWM input mode: | |
61 | * ___ ___ | |
62 | * TI[1, 2, 3 or 4]: ........._| |________| | |
63 | * ^0 ^1 ^2 | |
64 | * . . . | |
65 | * . . XXXXX | |
66 | * . . XXXXX | | |
67 | * . XXXXX . | | |
68 | * XXXXX . . | | |
69 | * COUNTER: ______XXXXX . . . |_XXX | |
70 | * start^ . . . ^stop | |
71 | * . . . . | |
72 | * v v . v | |
73 | * v | |
74 | * CCR1/CCR3: tx..........t0...........t2 | |
75 | * CCR2/CCR4: tx..............t1......... | |
76 | * | |
77 | * DMA burst transfer: | | | |
78 | * v v | |
79 | * DMA buffer: { t0, tx } { t2, t1 } | |
80 | * DMA done: ^ | |
81 | * | |
82 | * 0: IC1/3 snapchot on rising edge: counter value -> CCR1/CCR3 | |
83 | * + DMA transfer CCR[1/3] & CCR[2/4] values (t0, tx: doesn't care) | |
84 | * 1: IC2/4 snapchot on falling edge: counter value -> CCR2/CCR4 | |
85 | * 2: IC1/3 snapchot on rising edge: counter value -> CCR1/CCR3 | |
86 | * + DMA transfer CCR[1/3] & CCR[2/4] values (t2, t1) | |
87 | * | |
88 | * DMA done, compute: | |
89 | * - Period = t2 - t0 | |
90 | * - Duty cycle = t1 - t0 | |
91 | */ | |
fbde1289 | 92 | static int stm32_pwm_raw_capture(struct pwm_chip *chip, struct pwm_device *pwm, |
53e38fe7 FG |
93 | unsigned long tmo_ms, u32 *raw_prd, |
94 | u32 *raw_dty) | |
95 | { | |
fbde1289 UKK |
96 | struct stm32_pwm *priv = to_stm32_pwm_dev(chip); |
97 | struct device *parent = pwmchip_parent(chip)->parent; | |
53e38fe7 FG |
98 | enum stm32_timers_dmas dma_id; |
99 | u32 ccen, ccr; | |
100 | int ret; | |
101 | ||
102 | /* Ensure registers have been updated, enable counter and capture */ | |
632ae5d7 UKK |
103 | regmap_set_bits(priv->regmap, TIM_EGR, TIM_EGR_UG); |
104 | regmap_set_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN); | |
53e38fe7 FG |
105 | |
106 | /* Use cc1 or cc3 DMA resp for PWM input channels 1 & 2 or 3 & 4 */ | |
107 | dma_id = pwm->hwpwm < 2 ? STM32_TIMERS_DMA_CH1 : STM32_TIMERS_DMA_CH3; | |
108 | ccen = pwm->hwpwm < 2 ? TIM_CCER_CC12E : TIM_CCER_CC34E; | |
109 | ccr = pwm->hwpwm < 2 ? TIM_CCR1 : TIM_CCR3; | |
632ae5d7 | 110 | regmap_set_bits(priv->regmap, TIM_CCER, ccen); |
53e38fe7 FG |
111 | |
112 | /* | |
113 | * Timer DMA burst mode. Request 2 registers, 2 bursts, to get both | |
114 | * CCR1 & CCR2 (or CCR3 & CCR4) on each capture event. | |
115 | * We'll get two capture snapchots: { CCR1, CCR2 }, { CCR1, CCR2 } | |
116 | * or { CCR3, CCR4 }, { CCR3, CCR4 } | |
117 | */ | |
118 | ret = stm32_timers_dma_burst_read(parent, priv->capture, dma_id, ccr, 2, | |
119 | 2, tmo_ms); | |
120 | if (ret) | |
121 | goto stop; | |
122 | ||
123 | /* Period: t2 - t0 (take care of counter overflow) */ | |
124 | if (priv->capture[0] <= priv->capture[2]) | |
125 | *raw_prd = priv->capture[2] - priv->capture[0]; | |
126 | else | |
127 | *raw_prd = priv->max_arr - priv->capture[0] + priv->capture[2]; | |
128 | ||
129 | /* Duty cycle capture requires at least two capture units */ | |
130 | if (pwm->chip->npwm < 2) | |
131 | *raw_dty = 0; | |
132 | else if (priv->capture[0] <= priv->capture[3]) | |
133 | *raw_dty = priv->capture[3] - priv->capture[0]; | |
134 | else | |
135 | *raw_dty = priv->max_arr - priv->capture[0] + priv->capture[3]; | |
136 | ||
137 | if (*raw_dty > *raw_prd) { | |
138 | /* | |
139 | * Race beetween PWM input and DMA: it may happen | |
140 | * falling edge triggers new capture on TI2/4 before DMA | |
141 | * had a chance to read CCR2/4. It means capture[1] | |
142 | * contains period + duty_cycle. So, subtract period. | |
143 | */ | |
144 | *raw_dty -= *raw_prd; | |
145 | } | |
146 | ||
147 | stop: | |
632ae5d7 UKK |
148 | regmap_clear_bits(priv->regmap, TIM_CCER, ccen); |
149 | regmap_clear_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN); | |
53e38fe7 FG |
150 | |
151 | return ret; | |
152 | } | |
153 | ||
154 | static int stm32_pwm_capture(struct pwm_chip *chip, struct pwm_device *pwm, | |
155 | struct pwm_capture *result, unsigned long tmo_ms) | |
156 | { | |
157 | struct stm32_pwm *priv = to_stm32_pwm_dev(chip); | |
158 | unsigned long long prd, div, dty; | |
159 | unsigned long rate; | |
ab3a8978 | 160 | unsigned int psc = 0, icpsc, scale; |
a3b51be3 | 161 | u32 raw_prd = 0, raw_dty = 0; |
53e38fe7 FG |
162 | int ret = 0; |
163 | ||
164 | mutex_lock(&priv->lock); | |
165 | ||
166 | if (active_channels(priv)) { | |
167 | ret = -EBUSY; | |
168 | goto unlock; | |
169 | } | |
170 | ||
171 | ret = clk_enable(priv->clk); | |
172 | if (ret) { | |
fbde1289 | 173 | dev_err(pwmchip_parent(chip), "failed to enable counter clock\n"); |
53e38fe7 FG |
174 | goto unlock; |
175 | } | |
176 | ||
177 | rate = clk_get_rate(priv->clk); | |
178 | if (!rate) { | |
179 | ret = -EINVAL; | |
180 | goto clk_dis; | |
181 | } | |
182 | ||
183 | /* prescaler: fit timeout window provided by upper layer */ | |
184 | div = (unsigned long long)rate * (unsigned long long)tmo_ms; | |
185 | do_div(div, MSEC_PER_SEC); | |
186 | prd = div; | |
187 | while ((div > priv->max_arr) && (psc < MAX_TIM_PSC)) { | |
188 | psc++; | |
189 | div = prd; | |
190 | do_div(div, psc + 1); | |
191 | } | |
192 | regmap_write(priv->regmap, TIM_ARR, priv->max_arr); | |
193 | regmap_write(priv->regmap, TIM_PSC, psc); | |
194 | ||
d0a4564b OM |
195 | /* Reset input selector to its default input and disable slave mode */ |
196 | regmap_write(priv->regmap, TIM_TISEL, 0x0); | |
197 | regmap_write(priv->regmap, TIM_SMCR, 0x0); | |
198 | ||
53e38fe7 FG |
199 | /* Map TI1 or TI2 PWM input to IC1 & IC2 (or TI3/4 to IC3 & IC4) */ |
200 | regmap_update_bits(priv->regmap, | |
201 | pwm->hwpwm < 2 ? TIM_CCMR1 : TIM_CCMR2, | |
202 | TIM_CCMR_CC1S | TIM_CCMR_CC2S, pwm->hwpwm & 0x1 ? | |
203 | TIM_CCMR_CC1S_TI2 | TIM_CCMR_CC2S_TI2 : | |
204 | TIM_CCMR_CC1S_TI1 | TIM_CCMR_CC2S_TI1); | |
205 | ||
206 | /* Capture period on IC1/3 rising edge, duty cycle on IC2/4 falling. */ | |
207 | regmap_update_bits(priv->regmap, TIM_CCER, pwm->hwpwm < 2 ? | |
208 | TIM_CCER_CC12P : TIM_CCER_CC34P, pwm->hwpwm < 2 ? | |
209 | TIM_CCER_CC2P : TIM_CCER_CC4P); | |
210 | ||
fbde1289 | 211 | ret = stm32_pwm_raw_capture(chip, pwm, tmo_ms, &raw_prd, &raw_dty); |
53e38fe7 FG |
212 | if (ret) |
213 | goto stop; | |
214 | ||
d66ffb91 FG |
215 | /* |
216 | * Got a capture. Try to improve accuracy at high rates: | |
217 | * - decrease counter clock prescaler, scale up to max rate. | |
ab3a8978 | 218 | * - use input prescaler, capture once every /2 /4 or /8 edges. |
d66ffb91 FG |
219 | */ |
220 | if (raw_prd) { | |
221 | u32 max_arr = priv->max_arr - 0x1000; /* arbitrary margin */ | |
222 | ||
223 | scale = max_arr / min(max_arr, raw_prd); | |
224 | } else { | |
225 | scale = priv->max_arr; /* bellow resolution, use max scale */ | |
226 | } | |
227 | ||
228 | if (psc && scale > 1) { | |
229 | /* 2nd measure with new scale */ | |
230 | psc /= scale; | |
231 | regmap_write(priv->regmap, TIM_PSC, psc); | |
fbde1289 | 232 | ret = stm32_pwm_raw_capture(chip, pwm, tmo_ms, &raw_prd, |
d66ffb91 FG |
233 | &raw_dty); |
234 | if (ret) | |
235 | goto stop; | |
236 | } | |
237 | ||
ab3a8978 | 238 | /* Compute intermediate period not to exceed timeout at low rates */ |
53e38fe7 | 239 | prd = (unsigned long long)raw_prd * (psc + 1) * NSEC_PER_SEC; |
ab3a8978 FG |
240 | do_div(prd, rate); |
241 | ||
242 | for (icpsc = 0; icpsc < MAX_TIM_ICPSC ; icpsc++) { | |
243 | /* input prescaler: also keep arbitrary margin */ | |
244 | if (raw_prd >= (priv->max_arr - 0x1000) >> (icpsc + 1)) | |
245 | break; | |
246 | if (prd >= (tmo_ms * NSEC_PER_MSEC) >> (icpsc + 2)) | |
247 | break; | |
248 | } | |
249 | ||
250 | if (!icpsc) | |
251 | goto done; | |
252 | ||
253 | /* Last chance to improve period accuracy, using input prescaler */ | |
254 | regmap_update_bits(priv->regmap, | |
255 | pwm->hwpwm < 2 ? TIM_CCMR1 : TIM_CCMR2, | |
256 | TIM_CCMR_IC1PSC | TIM_CCMR_IC2PSC, | |
257 | FIELD_PREP(TIM_CCMR_IC1PSC, icpsc) | | |
258 | FIELD_PREP(TIM_CCMR_IC2PSC, icpsc)); | |
259 | ||
fbde1289 | 260 | ret = stm32_pwm_raw_capture(chip, pwm, tmo_ms, &raw_prd, &raw_dty); |
ab3a8978 FG |
261 | if (ret) |
262 | goto stop; | |
263 | ||
264 | if (raw_dty >= (raw_prd >> icpsc)) { | |
265 | /* | |
266 | * We may fall here using input prescaler, when input | |
267 | * capture starts on high side (before falling edge). | |
268 | * Example with icpsc to capture on each 4 events: | |
269 | * | |
270 | * start 1st capture 2nd capture | |
271 | * v v v | |
272 | * ___ _____ _____ _____ _____ ____ | |
273 | * TI1..4 |__| |__| |__| |__| |__| | |
274 | * v v . . . . . v v | |
275 | * icpsc1/3: . 0 . 1 . 2 . 3 . 0 | |
276 | * icpsc2/4: 0 1 2 3 0 | |
277 | * v v v v | |
278 | * CCR1/3 ......t0..............................t2 | |
279 | * CCR2/4 ..t1..............................t1'... | |
280 | * . . . | |
281 | * Capture0: .<----------------------------->. | |
282 | * Capture1: .<-------------------------->. . | |
283 | * . . . | |
284 | * Period: .<------> . . | |
285 | * Low side: .<>. | |
286 | * | |
287 | * Result: | |
288 | * - Period = Capture0 / icpsc | |
289 | * - Duty = Period - Low side = Period - (Capture0 - Capture1) | |
290 | */ | |
291 | raw_dty = (raw_prd >> icpsc) - (raw_prd - raw_dty); | |
292 | } | |
293 | ||
294 | done: | |
295 | prd = (unsigned long long)raw_prd * (psc + 1) * NSEC_PER_SEC; | |
296 | result->period = DIV_ROUND_UP_ULL(prd, rate << icpsc); | |
53e38fe7 FG |
297 | dty = (unsigned long long)raw_dty * (psc + 1) * NSEC_PER_SEC; |
298 | result->duty_cycle = DIV_ROUND_UP_ULL(dty, rate); | |
299 | stop: | |
300 | regmap_write(priv->regmap, TIM_CCER, 0); | |
301 | regmap_write(priv->regmap, pwm->hwpwm < 2 ? TIM_CCMR1 : TIM_CCMR2, 0); | |
302 | regmap_write(priv->regmap, TIM_PSC, 0); | |
303 | clk_dis: | |
304 | clk_disable(priv->clk); | |
305 | unlock: | |
306 | mutex_unlock(&priv->lock); | |
307 | ||
308 | return ret; | |
309 | } | |
310 | ||
c0504f59 | 311 | static int stm32_pwm_config(struct stm32_pwm *priv, unsigned int ch, |
d44d6356 | 312 | u64 duty_ns, u64 period_ns) |
7edf7369 | 313 | { |
8002fbee UKK |
314 | unsigned long long prd, dty; |
315 | unsigned long long prescaler; | |
7edf7369 BG |
316 | u32 ccmr, mask, shift; |
317 | ||
d44d6356 UKK |
318 | /* |
319 | * .probe() asserted that clk_get_rate() is not bigger than 1 GHz, so | |
8002fbee UKK |
320 | * the calculations here won't overflow. |
321 | * First we need to find the minimal value for prescaler such that | |
322 | * | |
323 | * period_ns * clkrate | |
324 | * ------------------------------ | |
325 | * NSEC_PER_SEC * (prescaler + 1) | |
326 | * | |
327 | * isn't bigger than max_arr. | |
d44d6356 | 328 | */ |
7edf7369 | 329 | |
8002fbee UKK |
330 | prescaler = mul_u64_u64_div_u64(period_ns, clk_get_rate(priv->clk), |
331 | (u64)NSEC_PER_SEC * priv->max_arr); | |
332 | if (prescaler > 0) | |
333 | prescaler -= 1; | |
7edf7369 BG |
334 | |
335 | if (prescaler > MAX_TIM_PSC) | |
336 | return -EINVAL; | |
337 | ||
8002fbee UKK |
338 | prd = mul_u64_u64_div_u64(period_ns, clk_get_rate(priv->clk), |
339 | (u64)NSEC_PER_SEC * (prescaler + 1)); | |
340 | ||
7edf7369 BG |
341 | /* |
342 | * All channels share the same prescaler and counter so when two | |
343 | * channels are active at the same time we can't change them | |
344 | */ | |
345 | if (active_channels(priv) & ~(1 << ch * 4)) { | |
346 | u32 psc, arr; | |
347 | ||
348 | regmap_read(priv->regmap, TIM_PSC, &psc); | |
349 | regmap_read(priv->regmap, TIM_ARR, &arr); | |
350 | ||
351 | if ((psc != prescaler) || (arr != prd - 1)) | |
352 | return -EBUSY; | |
353 | } | |
354 | ||
355 | regmap_write(priv->regmap, TIM_PSC, prescaler); | |
356 | regmap_write(priv->regmap, TIM_ARR, prd - 1); | |
632ae5d7 | 357 | regmap_set_bits(priv->regmap, TIM_CR1, TIM_CR1_ARPE); |
7edf7369 BG |
358 | |
359 | /* Calculate the duty cycles */ | |
d44d6356 UKK |
360 | dty = mul_u64_u64_div_u64(duty_ns, clk_get_rate(priv->clk), |
361 | (u64)NSEC_PER_SEC * (prescaler + 1)); | |
7edf7369 | 362 | |
e495f472 | 363 | regmap_write(priv->regmap, TIM_CCR1 + 4 * ch, dty); |
7edf7369 BG |
364 | |
365 | /* Configure output mode */ | |
366 | shift = (ch & 0x1) * CCMR_CHANNEL_SHIFT; | |
367 | ccmr = (TIM_CCMR_PE | TIM_CCMR_M1) << shift; | |
368 | mask = CCMR_CHANNEL_MASK << shift; | |
369 | ||
370 | if (ch < 2) | |
371 | regmap_update_bits(priv->regmap, TIM_CCMR1, mask, ccmr); | |
372 | else | |
373 | regmap_update_bits(priv->regmap, TIM_CCMR2, mask, ccmr); | |
374 | ||
632ae5d7 | 375 | regmap_set_bits(priv->regmap, TIM_BDTR, TIM_BDTR_MOE); |
7edf7369 BG |
376 | |
377 | return 0; | |
378 | } | |
379 | ||
c0504f59 | 380 | static int stm32_pwm_set_polarity(struct stm32_pwm *priv, unsigned int ch, |
7edf7369 BG |
381 | enum pwm_polarity polarity) |
382 | { | |
383 | u32 mask; | |
384 | ||
385 | mask = TIM_CCER_CC1P << (ch * 4); | |
386 | if (priv->have_complementary_output) | |
387 | mask |= TIM_CCER_CC1NP << (ch * 4); | |
388 | ||
389 | regmap_update_bits(priv->regmap, TIM_CCER, mask, | |
390 | polarity == PWM_POLARITY_NORMAL ? 0 : mask); | |
391 | ||
392 | return 0; | |
393 | } | |
394 | ||
c0504f59 | 395 | static int stm32_pwm_enable(struct stm32_pwm *priv, unsigned int ch) |
7edf7369 BG |
396 | { |
397 | u32 mask; | |
398 | int ret; | |
399 | ||
400 | ret = clk_enable(priv->clk); | |
401 | if (ret) | |
402 | return ret; | |
403 | ||
404 | /* Enable channel */ | |
405 | mask = TIM_CCER_CC1E << (ch * 4); | |
406 | if (priv->have_complementary_output) | |
407 | mask |= TIM_CCER_CC1NE << (ch * 4); | |
408 | ||
632ae5d7 | 409 | regmap_set_bits(priv->regmap, TIM_CCER, mask); |
7edf7369 BG |
410 | |
411 | /* Make sure that registers are updated */ | |
632ae5d7 | 412 | regmap_set_bits(priv->regmap, TIM_EGR, TIM_EGR_UG); |
7edf7369 BG |
413 | |
414 | /* Enable controller */ | |
632ae5d7 | 415 | regmap_set_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN); |
7edf7369 BG |
416 | |
417 | return 0; | |
418 | } | |
419 | ||
c0504f59 | 420 | static void stm32_pwm_disable(struct stm32_pwm *priv, unsigned int ch) |
7edf7369 BG |
421 | { |
422 | u32 mask; | |
423 | ||
424 | /* Disable channel */ | |
425 | mask = TIM_CCER_CC1E << (ch * 4); | |
426 | if (priv->have_complementary_output) | |
427 | mask |= TIM_CCER_CC1NE << (ch * 4); | |
428 | ||
632ae5d7 | 429 | regmap_clear_bits(priv->regmap, TIM_CCER, mask); |
7edf7369 BG |
430 | |
431 | /* When all channels are disabled, we can disable the controller */ | |
432 | if (!active_channels(priv)) | |
632ae5d7 | 433 | regmap_clear_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN); |
7edf7369 BG |
434 | |
435 | clk_disable(priv->clk); | |
436 | } | |
437 | ||
438 | static int stm32_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, | |
71523d18 | 439 | const struct pwm_state *state) |
7edf7369 BG |
440 | { |
441 | bool enabled; | |
442 | struct stm32_pwm *priv = to_stm32_pwm_dev(chip); | |
443 | int ret; | |
444 | ||
445 | enabled = pwm->state.enabled; | |
446 | ||
447 | if (enabled && !state->enabled) { | |
448 | stm32_pwm_disable(priv, pwm->hwpwm); | |
449 | return 0; | |
450 | } | |
451 | ||
452 | if (state->polarity != pwm->state.polarity) | |
453 | stm32_pwm_set_polarity(priv, pwm->hwpwm, state->polarity); | |
454 | ||
455 | ret = stm32_pwm_config(priv, pwm->hwpwm, | |
456 | state->duty_cycle, state->period); | |
457 | if (ret) | |
458 | return ret; | |
459 | ||
460 | if (!enabled && state->enabled) | |
461 | ret = stm32_pwm_enable(priv, pwm->hwpwm); | |
462 | ||
463 | return ret; | |
464 | } | |
465 | ||
4eb67a20 | 466 | static int stm32_pwm_apply_locked(struct pwm_chip *chip, struct pwm_device *pwm, |
71523d18 | 467 | const struct pwm_state *state) |
4eb67a20 FG |
468 | { |
469 | struct stm32_pwm *priv = to_stm32_pwm_dev(chip); | |
470 | int ret; | |
471 | ||
472 | /* protect common prescaler for all active channels */ | |
473 | mutex_lock(&priv->lock); | |
474 | ret = stm32_pwm_apply(chip, pwm, state); | |
475 | mutex_unlock(&priv->lock); | |
476 | ||
477 | return ret; | |
478 | } | |
479 | ||
e56ec7b7 PZ |
480 | static int stm32_pwm_get_state(struct pwm_chip *chip, |
481 | struct pwm_device *pwm, struct pwm_state *state) | |
482 | { | |
483 | struct stm32_pwm *priv = to_stm32_pwm_dev(chip); | |
484 | int ch = pwm->hwpwm; | |
485 | unsigned long rate; | |
486 | u32 ccer, psc, arr, ccr; | |
487 | u64 dty, prd; | |
488 | int ret; | |
489 | ||
490 | mutex_lock(&priv->lock); | |
491 | ||
492 | ret = regmap_read(priv->regmap, TIM_CCER, &ccer); | |
493 | if (ret) | |
494 | goto out; | |
495 | ||
496 | state->enabled = ccer & (TIM_CCER_CC1E << (ch * 4)); | |
497 | state->polarity = (ccer & (TIM_CCER_CC1P << (ch * 4))) ? | |
498 | PWM_POLARITY_INVERSED : PWM_POLARITY_NORMAL; | |
499 | ret = regmap_read(priv->regmap, TIM_PSC, &psc); | |
500 | if (ret) | |
501 | goto out; | |
502 | ret = regmap_read(priv->regmap, TIM_ARR, &arr); | |
503 | if (ret) | |
504 | goto out; | |
505 | ret = regmap_read(priv->regmap, TIM_CCR1 + 4 * ch, &ccr); | |
506 | if (ret) | |
507 | goto out; | |
508 | ||
509 | rate = clk_get_rate(priv->clk); | |
510 | ||
511 | prd = (u64)NSEC_PER_SEC * (psc + 1) * (arr + 1); | |
512 | state->period = DIV_ROUND_UP_ULL(prd, rate); | |
513 | dty = (u64)NSEC_PER_SEC * (psc + 1) * ccr; | |
514 | state->duty_cycle = DIV_ROUND_UP_ULL(dty, rate); | |
515 | ||
516 | out: | |
517 | mutex_unlock(&priv->lock); | |
518 | return ret; | |
519 | } | |
520 | ||
7edf7369 | 521 | static const struct pwm_ops stm32pwm_ops = { |
4eb67a20 | 522 | .apply = stm32_pwm_apply_locked, |
e56ec7b7 | 523 | .get_state = stm32_pwm_get_state, |
414c52b7 | 524 | .capture = IS_ENABLED(CONFIG_DMA_ENGINE) ? stm32_pwm_capture : NULL, |
7edf7369 BG |
525 | }; |
526 | ||
527 | static int stm32_pwm_set_breakinput(struct stm32_pwm *priv, | |
9e1b4999 | 528 | const struct stm32_breakinput *bi) |
7edf7369 | 529 | { |
9e1b4999 TR |
530 | u32 shift = TIM_BDTR_BKF_SHIFT(bi->index); |
531 | u32 bke = TIM_BDTR_BKE(bi->index); | |
532 | u32 bkp = TIM_BDTR_BKP(bi->index); | |
533 | u32 bkf = TIM_BDTR_BKF(bi->index); | |
8e536225 TR |
534 | u32 mask = bkf | bkp | bke; |
535 | u32 bdtr; | |
7edf7369 | 536 | |
9e1b4999 | 537 | bdtr = (bi->filter & TIM_BDTR_BKF_MASK) << shift | bke; |
7edf7369 | 538 | |
9e1b4999 | 539 | if (bi->level) |
8e536225 | 540 | bdtr |= bkp; |
7edf7369 BG |
541 | |
542 | regmap_update_bits(priv->regmap, TIM_BDTR, mask, bdtr); | |
543 | ||
544 | regmap_read(priv->regmap, TIM_BDTR, &bdtr); | |
545 | ||
546 | return (bdtr & bke) ? 0 : -EINVAL; | |
547 | } | |
548 | ||
0f9d2ecb FG |
549 | static int stm32_pwm_apply_breakinputs(struct stm32_pwm *priv) |
550 | { | |
551 | unsigned int i; | |
552 | int ret; | |
553 | ||
554 | for (i = 0; i < priv->num_breakinputs; i++) { | |
9e1b4999 | 555 | ret = stm32_pwm_set_breakinput(priv, &priv->breakinputs[i]); |
0f9d2ecb FG |
556 | if (ret < 0) |
557 | return ret; | |
558 | } | |
559 | ||
560 | return 0; | |
561 | } | |
562 | ||
563 | static int stm32_pwm_probe_breakinputs(struct stm32_pwm *priv, | |
7edf7369 BG |
564 | struct device_node *np) |
565 | { | |
0f9d2ecb | 566 | int nb, ret, array_size; |
8dfa620e | 567 | unsigned int i; |
7edf7369 BG |
568 | |
569 | nb = of_property_count_elems_of_size(np, "st,breakinput", | |
570 | sizeof(struct stm32_breakinput)); | |
571 | ||
572 | /* | |
573 | * Because "st,breakinput" parameter is optional do not make probe | |
574 | * failed if it doesn't exist. | |
575 | */ | |
576 | if (nb <= 0) | |
577 | return 0; | |
578 | ||
579 | if (nb > MAX_BREAKINPUT) | |
580 | return -EINVAL; | |
581 | ||
0f9d2ecb | 582 | priv->num_breakinputs = nb; |
7edf7369 BG |
583 | array_size = nb * sizeof(struct stm32_breakinput) / sizeof(u32); |
584 | ret = of_property_read_u32_array(np, "st,breakinput", | |
0f9d2ecb | 585 | (u32 *)priv->breakinputs, array_size); |
7edf7369 BG |
586 | if (ret) |
587 | return ret; | |
588 | ||
8dfa620e TR |
589 | for (i = 0; i < priv->num_breakinputs; i++) { |
590 | if (priv->breakinputs[i].index > 1 || | |
591 | priv->breakinputs[i].level > 1 || | |
592 | priv->breakinputs[i].filter > 15) | |
593 | return -EINVAL; | |
594 | } | |
595 | ||
0f9d2ecb | 596 | return stm32_pwm_apply_breakinputs(priv); |
7edf7369 BG |
597 | } |
598 | ||
599 | static void stm32_pwm_detect_complementary(struct stm32_pwm *priv) | |
600 | { | |
601 | u32 ccer; | |
602 | ||
603 | /* | |
604 | * If complementary bit doesn't exist writing 1 will have no | |
605 | * effect so we can detect it. | |
606 | */ | |
632ae5d7 | 607 | regmap_set_bits(priv->regmap, TIM_CCER, TIM_CCER_CC1NE); |
7edf7369 | 608 | regmap_read(priv->regmap, TIM_CCER, &ccer); |
632ae5d7 | 609 | regmap_clear_bits(priv->regmap, TIM_CCER, TIM_CCER_CC1NE); |
7edf7369 BG |
610 | |
611 | priv->have_complementary_output = (ccer != 0); | |
612 | } | |
613 | ||
e315bf70 | 614 | static unsigned int stm32_pwm_detect_channels(struct regmap *regmap, |
19f1016e | 615 | unsigned int *num_enabled) |
7edf7369 | 616 | { |
19f1016e | 617 | u32 ccer, ccer_backup; |
7edf7369 BG |
618 | |
619 | /* | |
620 | * If channels enable bits don't exist writing 1 will have no | |
621 | * effect so we can detect and count them. | |
622 | */ | |
e315bf70 UKK |
623 | regmap_read(regmap, TIM_CCER, &ccer_backup); |
624 | regmap_set_bits(regmap, TIM_CCER, TIM_CCER_CCXE); | |
625 | regmap_read(regmap, TIM_CCER, &ccer); | |
626 | regmap_write(regmap, TIM_CCER, ccer_backup); | |
19f1016e PZ |
627 | |
628 | *num_enabled = hweight32(ccer_backup & TIM_CCER_CCXE); | |
7edf7369 | 629 | |
41fa8f57 | 630 | return hweight32(ccer & TIM_CCER_CCXE); |
7edf7369 BG |
631 | } |
632 | ||
633 | static int stm32_pwm_probe(struct platform_device *pdev) | |
634 | { | |
635 | struct device *dev = &pdev->dev; | |
636 | struct device_node *np = dev->of_node; | |
637 | struct stm32_timers *ddata = dev_get_drvdata(pdev->dev.parent); | |
f2943071 | 638 | struct pwm_chip *chip; |
7edf7369 | 639 | struct stm32_pwm *priv; |
174821b7 | 640 | unsigned int npwm, num_enabled; |
19f1016e | 641 | unsigned int i; |
7edf7369 BG |
642 | int ret; |
643 | ||
174821b7 UKK |
644 | npwm = stm32_pwm_detect_channels(ddata->regmap, &num_enabled); |
645 | ||
646 | chip = devm_pwmchip_alloc(dev, npwm, sizeof(*priv)); | |
647 | if (IS_ERR(chip)) | |
648 | return PTR_ERR(chip); | |
649 | priv = to_stm32_pwm_dev(chip); | |
7edf7369 | 650 | |
4eb67a20 | 651 | mutex_init(&priv->lock); |
7edf7369 BG |
652 | priv->regmap = ddata->regmap; |
653 | priv->clk = ddata->clk; | |
654 | priv->max_arr = ddata->max_arr; | |
655 | ||
656 | if (!priv->regmap || !priv->clk) | |
80bd81cb UKK |
657 | return dev_err_probe(dev, -EINVAL, "Failed to get %s\n", |
658 | priv->regmap ? "clk" : "regmap"); | |
7edf7369 | 659 | |
0f9d2ecb | 660 | ret = stm32_pwm_probe_breakinputs(priv, np); |
7edf7369 | 661 | if (ret) |
80bd81cb UKK |
662 | return dev_err_probe(dev, ret, |
663 | "Failed to configure breakinputs\n"); | |
7edf7369 BG |
664 | |
665 | stm32_pwm_detect_complementary(priv); | |
666 | ||
d44d6356 UKK |
667 | ret = devm_clk_rate_exclusive_get(dev, priv->clk); |
668 | if (ret) | |
669 | return dev_err_probe(dev, ret, "Failed to lock clock\n"); | |
670 | ||
671 | /* | |
672 | * With the clk running with not more than 1 GHz the calculations in | |
673 | * .apply() won't overflow. | |
674 | */ | |
675 | if (clk_get_rate(priv->clk) > 1000000000) | |
676 | return dev_err_probe(dev, -EINVAL, "Failed to lock clock\n"); | |
677 | ||
f2943071 | 678 | chip->ops = &stm32pwm_ops; |
19f1016e PZ |
679 | |
680 | /* Initialize clock refcount to number of enabled PWM channels. */ | |
681 | for (i = 0; i < num_enabled; i++) | |
682 | clk_enable(priv->clk); | |
7edf7369 | 683 | |
f2943071 | 684 | ret = devm_pwmchip_add(dev, chip); |
7edf7369 | 685 | if (ret < 0) |
80bd81cb UKK |
686 | return dev_err_probe(dev, ret, |
687 | "Failed to register pwmchip\n"); | |
7edf7369 | 688 | |
f2943071 | 689 | platform_set_drvdata(pdev, chip); |
7edf7369 BG |
690 | |
691 | return 0; | |
692 | } | |
693 | ||
3d672776 | 694 | static int stm32_pwm_suspend(struct device *dev) |
2d3aa06b | 695 | { |
f2943071 UKK |
696 | struct pwm_chip *chip = dev_get_drvdata(dev); |
697 | struct stm32_pwm *priv = to_stm32_pwm_dev(chip); | |
2d3aa06b FG |
698 | unsigned int i; |
699 | u32 ccer, mask; | |
700 | ||
701 | /* Look for active channels */ | |
702 | ccer = active_channels(priv); | |
703 | ||
f2943071 | 704 | for (i = 0; i < chip->npwm; i++) { |
2d3aa06b FG |
705 | mask = TIM_CCER_CC1E << (i * 4); |
706 | if (ccer & mask) { | |
707 | dev_err(dev, "PWM %u still in use by consumer %s\n", | |
f2943071 | 708 | i, chip->pwms[i].label); |
2d3aa06b FG |
709 | return -EBUSY; |
710 | } | |
711 | } | |
712 | ||
713 | return pinctrl_pm_select_sleep_state(dev); | |
714 | } | |
715 | ||
3d672776 | 716 | static int stm32_pwm_resume(struct device *dev) |
2d3aa06b | 717 | { |
f2943071 UKK |
718 | struct pwm_chip *chip = dev_get_drvdata(dev); |
719 | struct stm32_pwm *priv = to_stm32_pwm_dev(chip); | |
2d3aa06b FG |
720 | int ret; |
721 | ||
722 | ret = pinctrl_pm_select_default_state(dev); | |
723 | if (ret) | |
724 | return ret; | |
725 | ||
726 | /* restore breakinput registers that may have been lost in low power */ | |
727 | return stm32_pwm_apply_breakinputs(priv); | |
728 | } | |
729 | ||
3d672776 | 730 | static DEFINE_SIMPLE_DEV_PM_OPS(stm32_pwm_pm_ops, stm32_pwm_suspend, stm32_pwm_resume); |
2d3aa06b | 731 | |
7edf7369 BG |
732 | static const struct of_device_id stm32_pwm_of_match[] = { |
733 | { .compatible = "st,stm32-pwm", }, | |
734 | { /* end node */ }, | |
735 | }; | |
736 | MODULE_DEVICE_TABLE(of, stm32_pwm_of_match); | |
737 | ||
738 | static struct platform_driver stm32_pwm_driver = { | |
739 | .probe = stm32_pwm_probe, | |
7edf7369 BG |
740 | .driver = { |
741 | .name = "stm32-pwm", | |
742 | .of_match_table = stm32_pwm_of_match, | |
3d672776 | 743 | .pm = pm_ptr(&stm32_pwm_pm_ops), |
7edf7369 BG |
744 | }, |
745 | }; | |
746 | module_platform_driver(stm32_pwm_driver); | |
747 | ||
748 | MODULE_ALIAS("platform:stm32-pwm"); | |
749 | MODULE_DESCRIPTION("STMicroelectronics STM32 PWM driver"); | |
750 | MODULE_LICENSE("GPL v2"); |