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v5.9
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * STM32 Timer Encoder and Counter driver
  4 *
  5 * Copyright (C) STMicroelectronics 2018
  6 *
  7 * Author: Benjamin Gaignard <benjamin.gaignard@st.com>
  8 *
  9 */
 10#include <linux/counter.h>
 11#include <linux/mfd/stm32-timers.h>
 12#include <linux/mod_devicetable.h>
 13#include <linux/module.h>
 14#include <linux/pinctrl/consumer.h>
 15#include <linux/platform_device.h>
 
 16
 17#define TIM_CCMR_CCXS	(BIT(8) | BIT(0))
 18#define TIM_CCMR_MASK	(TIM_CCMR_CC1S | TIM_CCMR_CC2S | \
 19			 TIM_CCMR_IC1F | TIM_CCMR_IC2F)
 20#define TIM_CCER_MASK	(TIM_CCER_CC1P | TIM_CCER_CC1NP | \
 21			 TIM_CCER_CC2P | TIM_CCER_CC2NP)
 22
 23struct stm32_timer_regs {
 24	u32 cr1;
 25	u32 cnt;
 26	u32 smcr;
 27	u32 arr;
 28};
 29
 30struct stm32_timer_cnt {
 31	struct counter_device counter;
 32	struct regmap *regmap;
 33	struct clk *clk;
 34	u32 ceiling;
 35	bool enabled;
 36	struct stm32_timer_regs bak;
 37};
 38
 39/**
 40 * enum stm32_count_function - enumerates stm32 timer counter encoder modes
 41 * @STM32_COUNT_SLAVE_MODE_DISABLED: counts on internal clock when CEN=1
 42 * @STM32_COUNT_ENCODER_MODE_1: counts TI1FP1 edges, depending on TI2FP2 level
 43 * @STM32_COUNT_ENCODER_MODE_2: counts TI2FP2 edges, depending on TI1FP1 level
 44 * @STM32_COUNT_ENCODER_MODE_3: counts on both TI1FP1 and TI2FP2 edges
 45 */
 46enum stm32_count_function {
 47	STM32_COUNT_SLAVE_MODE_DISABLED = -1,
 48	STM32_COUNT_ENCODER_MODE_1,
 49	STM32_COUNT_ENCODER_MODE_2,
 50	STM32_COUNT_ENCODER_MODE_3,
 51};
 52
 53static enum counter_count_function stm32_count_functions[] = {
 54	[STM32_COUNT_ENCODER_MODE_1] = COUNTER_COUNT_FUNCTION_QUADRATURE_X2_A,
 55	[STM32_COUNT_ENCODER_MODE_2] = COUNTER_COUNT_FUNCTION_QUADRATURE_X2_B,
 56	[STM32_COUNT_ENCODER_MODE_3] = COUNTER_COUNT_FUNCTION_QUADRATURE_X4,
 57};
 58
 59static int stm32_count_read(struct counter_device *counter,
 60			    struct counter_count *count, unsigned long *val)
 61{
 62	struct stm32_timer_cnt *const priv = counter->priv;
 63	u32 cnt;
 64
 65	regmap_read(priv->regmap, TIM_CNT, &cnt);
 66	*val = cnt;
 67
 68	return 0;
 69}
 70
 71static int stm32_count_write(struct counter_device *counter,
 72			     struct counter_count *count,
 73			     const unsigned long val)
 74{
 75	struct stm32_timer_cnt *const priv = counter->priv;
 
 76
 77	if (val > priv->ceiling)
 
 78		return -EINVAL;
 79
 80	return regmap_write(priv->regmap, TIM_CNT, val);
 81}
 82
 83static int stm32_count_function_get(struct counter_device *counter,
 84				    struct counter_count *count,
 85				    size_t *function)
 86{
 87	struct stm32_timer_cnt *const priv = counter->priv;
 88	u32 smcr;
 89
 90	regmap_read(priv->regmap, TIM_SMCR, &smcr);
 91
 92	switch (smcr & TIM_SMCR_SMS) {
 93	case 1:
 94		*function = STM32_COUNT_ENCODER_MODE_1;
 
 
 
 95		return 0;
 96	case 2:
 97		*function = STM32_COUNT_ENCODER_MODE_2;
 98		return 0;
 99	case 3:
100		*function = STM32_COUNT_ENCODER_MODE_3;
101		return 0;
 
 
102	}
103
104	return -EINVAL;
105}
106
107static int stm32_count_function_set(struct counter_device *counter,
108				    struct counter_count *count,
109				    size_t function)
110{
111	struct stm32_timer_cnt *const priv = counter->priv;
112	u32 cr1, sms;
113
114	switch (function) {
115	case STM32_COUNT_ENCODER_MODE_1:
116		sms = 1;
117		break;
118	case STM32_COUNT_ENCODER_MODE_2:
119		sms = 2;
120		break;
121	case STM32_COUNT_ENCODER_MODE_3:
122		sms = 3;
123		break;
124	default:
125		sms = 0;
126		break;
 
 
127	}
128
129	/* Store enable status */
130	regmap_read(priv->regmap, TIM_CR1, &cr1);
131
132	regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, 0);
133
134	/* TIMx_ARR register shouldn't be buffered (ARPE=0) */
135	regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_ARPE, 0);
136	regmap_write(priv->regmap, TIM_ARR, priv->ceiling);
137
138	regmap_update_bits(priv->regmap, TIM_SMCR, TIM_SMCR_SMS, sms);
139
140	/* Make sure that registers are updated */
141	regmap_update_bits(priv->regmap, TIM_EGR, TIM_EGR_UG, TIM_EGR_UG);
142
143	/* Restore the enable status */
144	regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, cr1);
145
146	return 0;
147}
148
149static ssize_t stm32_count_direction_read(struct counter_device *counter,
150				      struct counter_count *count,
151				      void *private, char *buf)
152{
153	struct stm32_timer_cnt *const priv = counter->priv;
154	const char *direction;
155	u32 cr1;
156
157	regmap_read(priv->regmap, TIM_CR1, &cr1);
158	direction = (cr1 & TIM_CR1_DIR) ? "backward" : "forward";
 
159
160	return scnprintf(buf, PAGE_SIZE, "%s\n", direction);
161}
162
163static ssize_t stm32_count_ceiling_read(struct counter_device *counter,
164					struct counter_count *count,
165					void *private, char *buf)
166{
167	struct stm32_timer_cnt *const priv = counter->priv;
168	u32 arr;
169
170	regmap_read(priv->regmap, TIM_ARR, &arr);
171
172	return snprintf(buf, PAGE_SIZE, "%u\n", arr);
 
 
173}
174
175static ssize_t stm32_count_ceiling_write(struct counter_device *counter,
176					 struct counter_count *count,
177					 void *private,
178					 const char *buf, size_t len)
179{
180	struct stm32_timer_cnt *const priv = counter->priv;
181	unsigned int ceiling;
182	int ret;
183
184	ret = kstrtouint(buf, 0, &ceiling);
185	if (ret)
186		return ret;
187
188	/* TIMx_ARR register shouldn't be buffered (ARPE=0) */
189	regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_ARPE, 0);
190	regmap_write(priv->regmap, TIM_ARR, ceiling);
191
192	priv->ceiling = ceiling;
193	return len;
194}
195
196static ssize_t stm32_count_enable_read(struct counter_device *counter,
197				       struct counter_count *count,
198				       void *private, char *buf)
199{
200	struct stm32_timer_cnt *const priv = counter->priv;
201	u32 cr1;
202
203	regmap_read(priv->regmap, TIM_CR1, &cr1);
204
205	return scnprintf(buf, PAGE_SIZE, "%d\n", (bool)(cr1 & TIM_CR1_CEN));
 
 
206}
207
208static ssize_t stm32_count_enable_write(struct counter_device *counter,
209					struct counter_count *count,
210					void *private,
211					const char *buf, size_t len)
212{
213	struct stm32_timer_cnt *const priv = counter->priv;
214	int err;
215	u32 cr1;
216	bool enable;
217
218	err = kstrtobool(buf, &enable);
219	if (err)
220		return err;
221
222	if (enable) {
223		regmap_read(priv->regmap, TIM_CR1, &cr1);
224		if (!(cr1 & TIM_CR1_CEN))
225			clk_enable(priv->clk);
226
227		regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN,
228				   TIM_CR1_CEN);
229	} else {
230		regmap_read(priv->regmap, TIM_CR1, &cr1);
231		regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, 0);
232		if (cr1 & TIM_CR1_CEN)
233			clk_disable(priv->clk);
234	}
235
236	/* Keep enabled state to properly handle low power states */
237	priv->enabled = enable;
238
239	return len;
240}
241
242static const struct counter_count_ext stm32_count_ext[] = {
243	{
244		.name = "direction",
245		.read = stm32_count_direction_read,
246	},
247	{
248		.name = "enable",
249		.read = stm32_count_enable_read,
250		.write = stm32_count_enable_write
251	},
252	{
253		.name = "ceiling",
254		.read = stm32_count_ceiling_read,
255		.write = stm32_count_ceiling_write
256	},
257};
258
259enum stm32_synapse_action {
260	STM32_SYNAPSE_ACTION_NONE,
261	STM32_SYNAPSE_ACTION_BOTH_EDGES
262};
263
264static enum counter_synapse_action stm32_synapse_actions[] = {
265	[STM32_SYNAPSE_ACTION_NONE] = COUNTER_SYNAPSE_ACTION_NONE,
266	[STM32_SYNAPSE_ACTION_BOTH_EDGES] = COUNTER_SYNAPSE_ACTION_BOTH_EDGES
267};
268
269static int stm32_action_get(struct counter_device *counter,
270			    struct counter_count *count,
271			    struct counter_synapse *synapse,
272			    size_t *action)
273{
274	size_t function;
275	int err;
276
277	/* Default action mode (e.g. STM32_COUNT_SLAVE_MODE_DISABLED) */
278	*action = STM32_SYNAPSE_ACTION_NONE;
279
280	err = stm32_count_function_get(counter, count, &function);
281	if (err)
282		return 0;
283
284	switch (function) {
285	case STM32_COUNT_ENCODER_MODE_1:
 
 
 
 
286		/* counts up/down on TI1FP1 edge depending on TI2FP2 level */
287		if (synapse->signal->id == count->synapses[0].signal->id)
288			*action = STM32_SYNAPSE_ACTION_BOTH_EDGES;
289		break;
290	case STM32_COUNT_ENCODER_MODE_2:
 
 
291		/* counts up/down on TI2FP2 edge depending on TI1FP1 level */
292		if (synapse->signal->id == count->synapses[1].signal->id)
293			*action = STM32_SYNAPSE_ACTION_BOTH_EDGES;
294		break;
295	case STM32_COUNT_ENCODER_MODE_3:
 
 
296		/* counts up/down on both TI1FP1 and TI2FP2 edges */
297		*action = STM32_SYNAPSE_ACTION_BOTH_EDGES;
298		break;
 
 
299	}
300
301	return 0;
302}
303
304static const struct counter_ops stm32_timer_cnt_ops = {
305	.count_read = stm32_count_read,
306	.count_write = stm32_count_write,
307	.function_get = stm32_count_function_get,
308	.function_set = stm32_count_function_set,
309	.action_get = stm32_action_get,
310};
311
312static struct counter_signal stm32_signals[] = {
313	{
314		.id = 0,
315		.name = "Channel 1 Quadrature A"
316	},
317	{
318		.id = 1,
319		.name = "Channel 1 Quadrature B"
320	}
321};
322
323static struct counter_synapse stm32_count_synapses[] = {
324	{
325		.actions_list = stm32_synapse_actions,
326		.num_actions = ARRAY_SIZE(stm32_synapse_actions),
327		.signal = &stm32_signals[0]
328	},
329	{
330		.actions_list = stm32_synapse_actions,
331		.num_actions = ARRAY_SIZE(stm32_synapse_actions),
332		.signal = &stm32_signals[1]
333	}
334};
335
336static struct counter_count stm32_counts = {
337	.id = 0,
338	.name = "Channel 1 Count",
339	.functions_list = stm32_count_functions,
340	.num_functions = ARRAY_SIZE(stm32_count_functions),
341	.synapses = stm32_count_synapses,
342	.num_synapses = ARRAY_SIZE(stm32_count_synapses),
343	.ext = stm32_count_ext,
344	.num_ext = ARRAY_SIZE(stm32_count_ext)
345};
346
347static int stm32_timer_cnt_probe(struct platform_device *pdev)
348{
349	struct stm32_timers *ddata = dev_get_drvdata(pdev->dev.parent);
350	struct device *dev = &pdev->dev;
351	struct stm32_timer_cnt *priv;
 
 
352
353	if (IS_ERR_OR_NULL(ddata))
354		return -EINVAL;
355
356	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
357	if (!priv)
358		return -ENOMEM;
359
 
 
360	priv->regmap = ddata->regmap;
361	priv->clk = ddata->clk;
362	priv->ceiling = ddata->max_arr;
363
364	priv->counter.name = dev_name(dev);
365	priv->counter.parent = dev;
366	priv->counter.ops = &stm32_timer_cnt_ops;
367	priv->counter.counts = &stm32_counts;
368	priv->counter.num_counts = 1;
369	priv->counter.signals = stm32_signals;
370	priv->counter.num_signals = ARRAY_SIZE(stm32_signals);
371	priv->counter.priv = priv;
372
373	platform_set_drvdata(pdev, priv);
374
375	/* Register Counter device */
376	return devm_counter_register(dev, &priv->counter);
 
 
 
 
377}
378
379static int __maybe_unused stm32_timer_cnt_suspend(struct device *dev)
380{
381	struct stm32_timer_cnt *priv = dev_get_drvdata(dev);
382
383	/* Only take care of enabled counter: don't disturb other MFD child */
384	if (priv->enabled) {
385		/* Backup registers that may get lost in low power mode */
386		regmap_read(priv->regmap, TIM_SMCR, &priv->bak.smcr);
387		regmap_read(priv->regmap, TIM_ARR, &priv->bak.arr);
388		regmap_read(priv->regmap, TIM_CNT, &priv->bak.cnt);
389		regmap_read(priv->regmap, TIM_CR1, &priv->bak.cr1);
390
391		/* Disable the counter */
392		regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, 0);
393		clk_disable(priv->clk);
394	}
395
396	return pinctrl_pm_select_sleep_state(dev);
397}
398
399static int __maybe_unused stm32_timer_cnt_resume(struct device *dev)
400{
401	struct stm32_timer_cnt *priv = dev_get_drvdata(dev);
402	int ret;
403
404	ret = pinctrl_pm_select_default_state(dev);
405	if (ret)
406		return ret;
407
408	if (priv->enabled) {
409		clk_enable(priv->clk);
410
411		/* Restore registers that may have been lost */
412		regmap_write(priv->regmap, TIM_SMCR, priv->bak.smcr);
413		regmap_write(priv->regmap, TIM_ARR, priv->bak.arr);
414		regmap_write(priv->regmap, TIM_CNT, priv->bak.cnt);
415
416		/* Also re-enables the counter */
417		regmap_write(priv->regmap, TIM_CR1, priv->bak.cr1);
418	}
419
420	return 0;
421}
422
423static SIMPLE_DEV_PM_OPS(stm32_timer_cnt_pm_ops, stm32_timer_cnt_suspend,
424			 stm32_timer_cnt_resume);
425
426static const struct of_device_id stm32_timer_cnt_of_match[] = {
427	{ .compatible = "st,stm32-timer-counter", },
428	{},
429};
430MODULE_DEVICE_TABLE(of, stm32_timer_cnt_of_match);
431
432static struct platform_driver stm32_timer_cnt_driver = {
433	.probe = stm32_timer_cnt_probe,
434	.driver = {
435		.name = "stm32-timer-counter",
436		.of_match_table = stm32_timer_cnt_of_match,
437		.pm = &stm32_timer_cnt_pm_ops,
438	},
439};
440module_platform_driver(stm32_timer_cnt_driver);
441
442MODULE_AUTHOR("Benjamin Gaignard <benjamin.gaignard@st.com>");
443MODULE_ALIAS("platform:stm32-timer-counter");
444MODULE_DESCRIPTION("STMicroelectronics STM32 TIMER counter driver");
445MODULE_LICENSE("GPL v2");
v6.2
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * STM32 Timer Encoder and Counter driver
  4 *
  5 * Copyright (C) STMicroelectronics 2018
  6 *
  7 * Author: Benjamin Gaignard <benjamin.gaignard@st.com>
  8 *
  9 */
 10#include <linux/counter.h>
 11#include <linux/mfd/stm32-timers.h>
 12#include <linux/mod_devicetable.h>
 13#include <linux/module.h>
 14#include <linux/pinctrl/consumer.h>
 15#include <linux/platform_device.h>
 16#include <linux/types.h>
 17
 18#define TIM_CCMR_CCXS	(BIT(8) | BIT(0))
 19#define TIM_CCMR_MASK	(TIM_CCMR_CC1S | TIM_CCMR_CC2S | \
 20			 TIM_CCMR_IC1F | TIM_CCMR_IC2F)
 21#define TIM_CCER_MASK	(TIM_CCER_CC1P | TIM_CCER_CC1NP | \
 22			 TIM_CCER_CC2P | TIM_CCER_CC2NP)
 23
 24struct stm32_timer_regs {
 25	u32 cr1;
 26	u32 cnt;
 27	u32 smcr;
 28	u32 arr;
 29};
 30
 31struct stm32_timer_cnt {
 
 32	struct regmap *regmap;
 33	struct clk *clk;
 34	u32 max_arr;
 35	bool enabled;
 36	struct stm32_timer_regs bak;
 37};
 38
 39static const enum counter_function stm32_count_functions[] = {
 40	COUNTER_FUNCTION_INCREASE,
 41	COUNTER_FUNCTION_QUADRATURE_X2_A,
 42	COUNTER_FUNCTION_QUADRATURE_X2_B,
 43	COUNTER_FUNCTION_QUADRATURE_X4,
 
 
 
 
 
 
 
 
 
 
 
 
 
 44};
 45
 46static int stm32_count_read(struct counter_device *counter,
 47			    struct counter_count *count, u64 *val)
 48{
 49	struct stm32_timer_cnt *const priv = counter_priv(counter);
 50	u32 cnt;
 51
 52	regmap_read(priv->regmap, TIM_CNT, &cnt);
 53	*val = cnt;
 54
 55	return 0;
 56}
 57
 58static int stm32_count_write(struct counter_device *counter,
 59			     struct counter_count *count, const u64 val)
 
 60{
 61	struct stm32_timer_cnt *const priv = counter_priv(counter);
 62	u32 ceiling;
 63
 64	regmap_read(priv->regmap, TIM_ARR, &ceiling);
 65	if (val > ceiling)
 66		return -EINVAL;
 67
 68	return regmap_write(priv->regmap, TIM_CNT, val);
 69}
 70
 71static int stm32_count_function_read(struct counter_device *counter,
 72				     struct counter_count *count,
 73				     enum counter_function *function)
 74{
 75	struct stm32_timer_cnt *const priv = counter_priv(counter);
 76	u32 smcr;
 77
 78	regmap_read(priv->regmap, TIM_SMCR, &smcr);
 79
 80	switch (smcr & TIM_SMCR_SMS) {
 81	case TIM_SMCR_SMS_SLAVE_MODE_DISABLED:
 82		*function = COUNTER_FUNCTION_INCREASE;
 83		return 0;
 84	case TIM_SMCR_SMS_ENCODER_MODE_1:
 85		*function = COUNTER_FUNCTION_QUADRATURE_X2_A;
 86		return 0;
 87	case TIM_SMCR_SMS_ENCODER_MODE_2:
 88		*function = COUNTER_FUNCTION_QUADRATURE_X2_B;
 89		return 0;
 90	case TIM_SMCR_SMS_ENCODER_MODE_3:
 91		*function = COUNTER_FUNCTION_QUADRATURE_X4;
 92		return 0;
 93	default:
 94		return -EINVAL;
 95	}
 
 
 96}
 97
 98static int stm32_count_function_write(struct counter_device *counter,
 99				      struct counter_count *count,
100				      enum counter_function function)
101{
102	struct stm32_timer_cnt *const priv = counter_priv(counter);
103	u32 cr1, sms;
104
105	switch (function) {
106	case COUNTER_FUNCTION_INCREASE:
107		sms = TIM_SMCR_SMS_SLAVE_MODE_DISABLED;
108		break;
109	case COUNTER_FUNCTION_QUADRATURE_X2_A:
110		sms = TIM_SMCR_SMS_ENCODER_MODE_1;
111		break;
112	case COUNTER_FUNCTION_QUADRATURE_X2_B:
113		sms = TIM_SMCR_SMS_ENCODER_MODE_2;
114		break;
115	case COUNTER_FUNCTION_QUADRATURE_X4:
116		sms = TIM_SMCR_SMS_ENCODER_MODE_3;
117		break;
118	default:
119		return -EINVAL;
120	}
121
122	/* Store enable status */
123	regmap_read(priv->regmap, TIM_CR1, &cr1);
124
125	regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, 0);
126
 
 
 
 
127	regmap_update_bits(priv->regmap, TIM_SMCR, TIM_SMCR_SMS, sms);
128
129	/* Make sure that registers are updated */
130	regmap_update_bits(priv->regmap, TIM_EGR, TIM_EGR_UG, TIM_EGR_UG);
131
132	/* Restore the enable status */
133	regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, cr1);
134
135	return 0;
136}
137
138static int stm32_count_direction_read(struct counter_device *counter,
139				      struct counter_count *count,
140				      enum counter_count_direction *direction)
141{
142	struct stm32_timer_cnt *const priv = counter_priv(counter);
 
143	u32 cr1;
144
145	regmap_read(priv->regmap, TIM_CR1, &cr1);
146	*direction = (cr1 & TIM_CR1_DIR) ? COUNTER_COUNT_DIRECTION_BACKWARD :
147		COUNTER_COUNT_DIRECTION_FORWARD;
148
149	return 0;
150}
151
152static int stm32_count_ceiling_read(struct counter_device *counter,
153				    struct counter_count *count, u64 *ceiling)
 
154{
155	struct stm32_timer_cnt *const priv = counter_priv(counter);
156	u32 arr;
157
158	regmap_read(priv->regmap, TIM_ARR, &arr);
159
160	*ceiling = arr;
161
162	return 0;
163}
164
165static int stm32_count_ceiling_write(struct counter_device *counter,
166				     struct counter_count *count, u64 ceiling)
 
 
167{
168	struct stm32_timer_cnt *const priv = counter_priv(counter);
 
 
169
170	if (ceiling > priv->max_arr)
171		return -ERANGE;
 
172
173	/* TIMx_ARR register shouldn't be buffered (ARPE=0) */
174	regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_ARPE, 0);
175	regmap_write(priv->regmap, TIM_ARR, ceiling);
176
177	return 0;
 
178}
179
180static int stm32_count_enable_read(struct counter_device *counter,
181				   struct counter_count *count, u8 *enable)
 
182{
183	struct stm32_timer_cnt *const priv = counter_priv(counter);
184	u32 cr1;
185
186	regmap_read(priv->regmap, TIM_CR1, &cr1);
187
188	*enable = cr1 & TIM_CR1_CEN;
189
190	return 0;
191}
192
193static int stm32_count_enable_write(struct counter_device *counter,
194				    struct counter_count *count, u8 enable)
 
 
195{
196	struct stm32_timer_cnt *const priv = counter_priv(counter);
 
197	u32 cr1;
 
 
 
 
 
198
199	if (enable) {
200		regmap_read(priv->regmap, TIM_CR1, &cr1);
201		if (!(cr1 & TIM_CR1_CEN))
202			clk_enable(priv->clk);
203
204		regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN,
205				   TIM_CR1_CEN);
206	} else {
207		regmap_read(priv->regmap, TIM_CR1, &cr1);
208		regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, 0);
209		if (cr1 & TIM_CR1_CEN)
210			clk_disable(priv->clk);
211	}
212
213	/* Keep enabled state to properly handle low power states */
214	priv->enabled = enable;
215
216	return 0;
217}
218
219static struct counter_comp stm32_count_ext[] = {
220	COUNTER_COMP_DIRECTION(stm32_count_direction_read),
221	COUNTER_COMP_ENABLE(stm32_count_enable_read, stm32_count_enable_write),
222	COUNTER_COMP_CEILING(stm32_count_ceiling_read,
223			     stm32_count_ceiling_write),
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
224};
225
226static const enum counter_synapse_action stm32_synapse_actions[] = {
227	COUNTER_SYNAPSE_ACTION_NONE,
228	COUNTER_SYNAPSE_ACTION_BOTH_EDGES
229};
230
231static int stm32_action_read(struct counter_device *counter,
232			     struct counter_count *count,
233			     struct counter_synapse *synapse,
234			     enum counter_synapse_action *action)
235{
236	enum counter_function function;
237	int err;
238
239	err = stm32_count_function_read(counter, count, &function);
 
 
 
240	if (err)
241		return err;
242
243	switch (function) {
244	case COUNTER_FUNCTION_INCREASE:
245		/* counts on internal clock when CEN=1 */
246		*action = COUNTER_SYNAPSE_ACTION_NONE;
247		return 0;
248	case COUNTER_FUNCTION_QUADRATURE_X2_A:
249		/* counts up/down on TI1FP1 edge depending on TI2FP2 level */
250		if (synapse->signal->id == count->synapses[0].signal->id)
251			*action = COUNTER_SYNAPSE_ACTION_BOTH_EDGES;
252		else
253			*action = COUNTER_SYNAPSE_ACTION_NONE;
254		return 0;
255	case COUNTER_FUNCTION_QUADRATURE_X2_B:
256		/* counts up/down on TI2FP2 edge depending on TI1FP1 level */
257		if (synapse->signal->id == count->synapses[1].signal->id)
258			*action = COUNTER_SYNAPSE_ACTION_BOTH_EDGES;
259		else
260			*action = COUNTER_SYNAPSE_ACTION_NONE;
261		return 0;
262	case COUNTER_FUNCTION_QUADRATURE_X4:
263		/* counts up/down on both TI1FP1 and TI2FP2 edges */
264		*action = COUNTER_SYNAPSE_ACTION_BOTH_EDGES;
265		return 0;
266	default:
267		return -EINVAL;
268	}
 
 
269}
270
271static const struct counter_ops stm32_timer_cnt_ops = {
272	.count_read = stm32_count_read,
273	.count_write = stm32_count_write,
274	.function_read = stm32_count_function_read,
275	.function_write = stm32_count_function_write,
276	.action_read = stm32_action_read,
277};
278
279static struct counter_signal stm32_signals[] = {
280	{
281		.id = 0,
282		.name = "Channel 1 Quadrature A"
283	},
284	{
285		.id = 1,
286		.name = "Channel 1 Quadrature B"
287	}
288};
289
290static struct counter_synapse stm32_count_synapses[] = {
291	{
292		.actions_list = stm32_synapse_actions,
293		.num_actions = ARRAY_SIZE(stm32_synapse_actions),
294		.signal = &stm32_signals[0]
295	},
296	{
297		.actions_list = stm32_synapse_actions,
298		.num_actions = ARRAY_SIZE(stm32_synapse_actions),
299		.signal = &stm32_signals[1]
300	}
301};
302
303static struct counter_count stm32_counts = {
304	.id = 0,
305	.name = "Channel 1 Count",
306	.functions_list = stm32_count_functions,
307	.num_functions = ARRAY_SIZE(stm32_count_functions),
308	.synapses = stm32_count_synapses,
309	.num_synapses = ARRAY_SIZE(stm32_count_synapses),
310	.ext = stm32_count_ext,
311	.num_ext = ARRAY_SIZE(stm32_count_ext)
312};
313
314static int stm32_timer_cnt_probe(struct platform_device *pdev)
315{
316	struct stm32_timers *ddata = dev_get_drvdata(pdev->dev.parent);
317	struct device *dev = &pdev->dev;
318	struct stm32_timer_cnt *priv;
319	struct counter_device *counter;
320	int ret;
321
322	if (IS_ERR_OR_NULL(ddata))
323		return -EINVAL;
324
325	counter = devm_counter_alloc(dev, sizeof(*priv));
326	if (!counter)
327		return -ENOMEM;
328
329	priv = counter_priv(counter);
330
331	priv->regmap = ddata->regmap;
332	priv->clk = ddata->clk;
333	priv->max_arr = ddata->max_arr;
334
335	counter->name = dev_name(dev);
336	counter->parent = dev;
337	counter->ops = &stm32_timer_cnt_ops;
338	counter->counts = &stm32_counts;
339	counter->num_counts = 1;
340	counter->signals = stm32_signals;
341	counter->num_signals = ARRAY_SIZE(stm32_signals);
 
342
343	platform_set_drvdata(pdev, priv);
344
345	/* Register Counter device */
346	ret = devm_counter_add(dev, counter);
347	if (ret < 0)
348		dev_err_probe(dev, ret, "Failed to add counter\n");
349
350	return ret;
351}
352
353static int __maybe_unused stm32_timer_cnt_suspend(struct device *dev)
354{
355	struct stm32_timer_cnt *priv = dev_get_drvdata(dev);
356
357	/* Only take care of enabled counter: don't disturb other MFD child */
358	if (priv->enabled) {
359		/* Backup registers that may get lost in low power mode */
360		regmap_read(priv->regmap, TIM_SMCR, &priv->bak.smcr);
361		regmap_read(priv->regmap, TIM_ARR, &priv->bak.arr);
362		regmap_read(priv->regmap, TIM_CNT, &priv->bak.cnt);
363		regmap_read(priv->regmap, TIM_CR1, &priv->bak.cr1);
364
365		/* Disable the counter */
366		regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, 0);
367		clk_disable(priv->clk);
368	}
369
370	return pinctrl_pm_select_sleep_state(dev);
371}
372
373static int __maybe_unused stm32_timer_cnt_resume(struct device *dev)
374{
375	struct stm32_timer_cnt *priv = dev_get_drvdata(dev);
376	int ret;
377
378	ret = pinctrl_pm_select_default_state(dev);
379	if (ret)
380		return ret;
381
382	if (priv->enabled) {
383		clk_enable(priv->clk);
384
385		/* Restore registers that may have been lost */
386		regmap_write(priv->regmap, TIM_SMCR, priv->bak.smcr);
387		regmap_write(priv->regmap, TIM_ARR, priv->bak.arr);
388		regmap_write(priv->regmap, TIM_CNT, priv->bak.cnt);
389
390		/* Also re-enables the counter */
391		regmap_write(priv->regmap, TIM_CR1, priv->bak.cr1);
392	}
393
394	return 0;
395}
396
397static SIMPLE_DEV_PM_OPS(stm32_timer_cnt_pm_ops, stm32_timer_cnt_suspend,
398			 stm32_timer_cnt_resume);
399
400static const struct of_device_id stm32_timer_cnt_of_match[] = {
401	{ .compatible = "st,stm32-timer-counter", },
402	{},
403};
404MODULE_DEVICE_TABLE(of, stm32_timer_cnt_of_match);
405
406static struct platform_driver stm32_timer_cnt_driver = {
407	.probe = stm32_timer_cnt_probe,
408	.driver = {
409		.name = "stm32-timer-counter",
410		.of_match_table = stm32_timer_cnt_of_match,
411		.pm = &stm32_timer_cnt_pm_ops,
412	},
413};
414module_platform_driver(stm32_timer_cnt_driver);
415
416MODULE_AUTHOR("Benjamin Gaignard <benjamin.gaignard@st.com>");
417MODULE_ALIAS("platform:stm32-timer-counter");
418MODULE_DESCRIPTION("STMicroelectronics STM32 TIMER counter driver");
419MODULE_LICENSE("GPL v2");
420MODULE_IMPORT_NS(COUNTER);