1 files changed, 192 insertions, 155 deletions

diff --git a/drivers/counter/stm32-timer-cnt.c b/drivers/counter/stm32-timer-cnt.c
index 3eafccec3beb..9bf20a5d6bda 100644
--- a/drivers/counter/stm32-timer-cnt.c
+++ b/drivers/counter/stm32-timer-cnt.c
@@ -8,11 +8,12 @@
  *
  */
 #include <linux/counter.h>
-#include <linux/iio/iio.h>
-#include <linux/iio/types.h>
 #include <linux/mfd/stm32-timers.h>
+#include <linux/mod_devicetable.h>
 #include <linux/module.h>
+#include <linux/pinctrl/consumer.h>
 #include <linux/platform_device.h>
+#include <linux/types.h>
 
 #define TIM_CCMR_CCXS	(BIT(8) | BIT(0))
 #define TIM_CCMR_MASK	(TIM_CCMR_CC1S | TIM_CCMR_CC2S | \
@@ -20,37 +21,32 @@
 #define TIM_CCER_MASK	(TIM_CCER_CC1P | TIM_CCER_CC1NP | \
 			 TIM_CCER_CC2P | TIM_CCER_CC2NP)
 
+struct stm32_timer_regs {
+	u32 cr1;
+	u32 cnt;
+	u32 smcr;
+	u32 arr;
+};
+
 struct stm32_timer_cnt {
-	struct counter_device counter;
 	struct regmap *regmap;
 	struct clk *clk;
-	u32 ceiling;
+	u32 max_arr;
+	bool enabled;
+	struct stm32_timer_regs bak;
 };
 
-/**
- * enum stm32_count_function - enumerates stm32 timer counter encoder modes
- * @STM32_COUNT_SLAVE_MODE_DISABLED: counts on internal clock when CEN=1
- * @STM32_COUNT_ENCODER_MODE_1: counts TI1FP1 edges, depending on TI2FP2 level
- * @STM32_COUNT_ENCODER_MODE_2: counts TI2FP2 edges, depending on TI1FP1 level
- * @STM32_COUNT_ENCODER_MODE_3: counts on both TI1FP1 and TI2FP2 edges
- */
-enum stm32_count_function {
-	STM32_COUNT_SLAVE_MODE_DISABLED = -1,
-	STM32_COUNT_ENCODER_MODE_1,
-	STM32_COUNT_ENCODER_MODE_2,
-	STM32_COUNT_ENCODER_MODE_3,
-};
-
-static enum counter_count_function stm32_count_functions[] = {
-	[STM32_COUNT_ENCODER_MODE_1] = COUNTER_COUNT_FUNCTION_QUADRATURE_X2_A,
-	[STM32_COUNT_ENCODER_MODE_2] = COUNTER_COUNT_FUNCTION_QUADRATURE_X2_B,
-	[STM32_COUNT_ENCODER_MODE_3] = COUNTER_COUNT_FUNCTION_QUADRATURE_X4,
+static const enum counter_function stm32_count_functions[] = {
+	COUNTER_FUNCTION_INCREASE,
+	COUNTER_FUNCTION_QUADRATURE_X2_A,
+	COUNTER_FUNCTION_QUADRATURE_X2_B,
+	COUNTER_FUNCTION_QUADRATURE_X4,
 };
 
 static int stm32_count_read(struct counter_device *counter,
-			    struct counter_count *count, unsigned long *val)
+			    struct counter_count *count, u64 *val)
 {
-	struct stm32_timer_cnt *const priv = counter->priv;
+	struct stm32_timer_cnt *const priv = counter_priv(counter);
 	u32 cnt;
 
 	regmap_read(priv->regmap, TIM_CNT, &cnt);
@@ -60,61 +56,67 @@ static int stm32_count_read(struct counter_device *counter,
 }
 
 static int stm32_count_write(struct counter_device *counter,
-			     struct counter_count *count,
-			     const unsigned long val)
+			     struct counter_count *count, const u64 val)
 {
-	struct stm32_timer_cnt *const priv = counter->priv;
+	struct stm32_timer_cnt *const priv = counter_priv(counter);
+	u32 ceiling;
 
-	if (val > priv->ceiling)
+	regmap_read(priv->regmap, TIM_ARR, &ceiling);
+	if (val > ceiling)
 		return -EINVAL;
 
 	return regmap_write(priv->regmap, TIM_CNT, val);
 }
 
-static int stm32_count_function_get(struct counter_device *counter,
-				    struct counter_count *count,
-				    size_t *function)
+static int stm32_count_function_read(struct counter_device *counter,
+				     struct counter_count *count,
+				     enum counter_function *function)
 {
-	struct stm32_timer_cnt *const priv = counter->priv;
+	struct stm32_timer_cnt *const priv = counter_priv(counter);
 	u32 smcr;
 
 	regmap_read(priv->regmap, TIM_SMCR, &smcr);
 
 	switch (smcr & TIM_SMCR_SMS) {
-	case 1:
-		*function = STM32_COUNT_ENCODER_MODE_1;
+	case TIM_SMCR_SMS_SLAVE_MODE_DISABLED:
+		*function = COUNTER_FUNCTION_INCREASE;
+		return 0;
+	case TIM_SMCR_SMS_ENCODER_MODE_1:
+		*function = COUNTER_FUNCTION_QUADRATURE_X2_A;
 		return 0;
-	case 2:
-		*function = STM32_COUNT_ENCODER_MODE_2;
+	case TIM_SMCR_SMS_ENCODER_MODE_2:
+		*function = COUNTER_FUNCTION_QUADRATURE_X2_B;
 		return 0;
-	case 3:
-		*function = STM32_COUNT_ENCODER_MODE_3;
+	case TIM_SMCR_SMS_ENCODER_MODE_3:
+		*function = COUNTER_FUNCTION_QUADRATURE_X4;
 		return 0;
+	default:
+		return -EINVAL;
 	}
-
-	return -EINVAL;
 }
 
-static int stm32_count_function_set(struct counter_device *counter,
-				    struct counter_count *count,
-				    size_t function)
+static int stm32_count_function_write(struct counter_device *counter,
+				      struct counter_count *count,
+				      enum counter_function function)
 {
-	struct stm32_timer_cnt *const priv = counter->priv;
+	struct stm32_timer_cnt *const priv = counter_priv(counter);
 	u32 cr1, sms;
 
 	switch (function) {
-	case STM32_COUNT_ENCODER_MODE_1:
-		sms = 1;
+	case COUNTER_FUNCTION_INCREASE:
+		sms = TIM_SMCR_SMS_SLAVE_MODE_DISABLED;
 		break;
-	case STM32_COUNT_ENCODER_MODE_2:
-		sms = 2;
+	case COUNTER_FUNCTION_QUADRATURE_X2_A:
+		sms = TIM_SMCR_SMS_ENCODER_MODE_1;
 		break;
-	case STM32_COUNT_ENCODER_MODE_3:
-		sms = 3;
+	case COUNTER_FUNCTION_QUADRATURE_X2_B:
+		sms = TIM_SMCR_SMS_ENCODER_MODE_2;
 		break;
-	default:
-		sms = 0;
+	case COUNTER_FUNCTION_QUADRATURE_X4:
+		sms = TIM_SMCR_SMS_ENCODER_MODE_3;
 		break;
+	default:
+		return -EINVAL;
 	}
 
 	/* Store enable status */
@@ -122,10 +124,6 @@ static int stm32_count_function_set(struct counter_device *counter,
 
 	regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, 0);
 
-	/* TIMx_ARR register shouldn't be buffered (ARPE=0) */
-	regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_ARPE, 0);
-	regmap_write(priv->regmap, TIM_ARR, priv->ceiling);
-
 	regmap_update_bits(priv->regmap, TIM_SMCR, TIM_SMCR_SMS, sms);
 
 	/* Make sure that registers are updated */
@@ -137,78 +135,66 @@ static int stm32_count_function_set(struct counter_device *counter,
 	return 0;
 }
 
-static ssize_t stm32_count_direction_read(struct counter_device *counter,
+static int stm32_count_direction_read(struct counter_device *counter,
 				      struct counter_count *count,
-				      void *private, char *buf)
+				      enum counter_count_direction *direction)
 {
-	struct stm32_timer_cnt *const priv = counter->priv;
-	const char *direction;
+	struct stm32_timer_cnt *const priv = counter_priv(counter);
 	u32 cr1;
 
 	regmap_read(priv->regmap, TIM_CR1, &cr1);
-	direction = (cr1 & TIM_CR1_DIR) ? "backward" : "forward";
+	*direction = (cr1 & TIM_CR1_DIR) ? COUNTER_COUNT_DIRECTION_BACKWARD :
+		COUNTER_COUNT_DIRECTION_FORWARD;
 
-	return scnprintf(buf, PAGE_SIZE, "%s\n", direction);
+	return 0;
 }
 
-static ssize_t stm32_count_ceiling_read(struct counter_device *counter,
-					struct counter_count *count,
-					void *private, char *buf)
+static int stm32_count_ceiling_read(struct counter_device *counter,
+				    struct counter_count *count, u64 *ceiling)
 {
-	struct stm32_timer_cnt *const priv = counter->priv;
+	struct stm32_timer_cnt *const priv = counter_priv(counter);
 	u32 arr;
 
 	regmap_read(priv->regmap, TIM_ARR, &arr);
 
-	return snprintf(buf, PAGE_SIZE, "%u\n", arr);
+	*ceiling = arr;
+
+	return 0;
 }
 
-static ssize_t stm32_count_ceiling_write(struct counter_device *counter,
-					 struct counter_count *count,
-					 void *private,
-					 const char *buf, size_t len)
+static int stm32_count_ceiling_write(struct counter_device *counter,
+				     struct counter_count *count, u64 ceiling)
 {
-	struct stm32_timer_cnt *const priv = counter->priv;
-	unsigned int ceiling;
-	int ret;
+	struct stm32_timer_cnt *const priv = counter_priv(counter);
 
-	ret = kstrtouint(buf, 0, &ceiling);
-	if (ret)
-		return ret;
+	if (ceiling > priv->max_arr)
+		return -ERANGE;
 
 	/* TIMx_ARR register shouldn't be buffered (ARPE=0) */
 	regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_ARPE, 0);
 	regmap_write(priv->regmap, TIM_ARR, ceiling);
 
-	priv->ceiling = ceiling;
-	return len;
+	return 0;
 }
 
-static ssize_t stm32_count_enable_read(struct counter_device *counter,
-				       struct counter_count *count,
-				       void *private, char *buf)
+static int stm32_count_enable_read(struct counter_device *counter,
+				   struct counter_count *count, u8 *enable)
 {
-	struct stm32_timer_cnt *const priv = counter->priv;
+	struct stm32_timer_cnt *const priv = counter_priv(counter);
 	u32 cr1;
 
 	regmap_read(priv->regmap, TIM_CR1, &cr1);
 
-	return scnprintf(buf, PAGE_SIZE, "%d\n", (bool)(cr1 & TIM_CR1_CEN));
+	*enable = cr1 & TIM_CR1_CEN;
+
+	return 0;
 }
 
-static ssize_t stm32_count_enable_write(struct counter_device *counter,
-					struct counter_count *count,
-					void *private,
-					const char *buf, size_t len)
+static int stm32_count_enable_write(struct counter_device *counter,
+				    struct counter_count *count, u8 enable)
 {
-	struct stm32_timer_cnt *const priv = counter->priv;
-	int err;
+	struct stm32_timer_cnt *const priv = counter_priv(counter);
 	u32 cr1;
-	bool enable;
-
-	err = kstrtobool(buf, &enable);
-	if (err)
-		return err;
 
 	if (enable) {
 		regmap_read(priv->regmap, TIM_CR1, &cr1);
@@ -224,77 +210,70 @@ static ssize_t stm32_count_enable_write(struct counter_device *counter,
 			clk_disable(priv->clk);
 	}
 
-	return len;
-}
+	/* Keep enabled state to properly handle low power states */
+	priv->enabled = enable;
 
-static const struct counter_count_ext stm32_count_ext[] = {
-	{
-		.name = "direction",
-		.read = stm32_count_direction_read,
-	},
-	{
-		.name = "enable",
-		.read = stm32_count_enable_read,
-		.write = stm32_count_enable_write
-	},
-	{
-		.name = "ceiling",
-		.read = stm32_count_ceiling_read,
-		.write = stm32_count_ceiling_write
-	},
-};
+	return 0;
+}
 
-enum stm32_synapse_action {
-	STM32_SYNAPSE_ACTION_NONE,
-	STM32_SYNAPSE_ACTION_BOTH_EDGES
+static struct counter_comp stm32_count_ext[] = {
+	COUNTER_COMP_DIRECTION(stm32_count_direction_read),
+	COUNTER_COMP_ENABLE(stm32_count_enable_read, stm32_count_enable_write),
+	COUNTER_COMP_CEILING(stm32_count_ceiling_read,
+			     stm32_count_ceiling_write),
 };
 
-static enum counter_synapse_action stm32_synapse_actions[] = {
-	[STM32_SYNAPSE_ACTION_NONE] = COUNTER_SYNAPSE_ACTION_NONE,
-	[STM32_SYNAPSE_ACTION_BOTH_EDGES] = COUNTER_SYNAPSE_ACTION_BOTH_EDGES
+static const enum counter_synapse_action stm32_synapse_actions[] = {
+	COUNTER_SYNAPSE_ACTION_NONE,
+	COUNTER_SYNAPSE_ACTION_BOTH_EDGES
 };
 
-static int stm32_action_get(struct counter_device *counter,
-			    struct counter_count *count,
-			    struct counter_synapse *synapse,
-			    size_t *action)
+static int stm32_action_read(struct counter_device *counter,
+			     struct counter_count *count,
+			     struct counter_synapse *synapse,
+			     enum counter_synapse_action *action)
 {
-	size_t function;
+	enum counter_function function;
 	int err;
 
-	/* Default action mode (e.g. STM32_COUNT_SLAVE_MODE_DISABLED) */
-	*action = STM32_SYNAPSE_ACTION_NONE;
-
-	err = stm32_count_function_get(counter, count, &function);
+	err = stm32_count_function_read(counter, count, &function);
 	if (err)
-		return 0;
+		return err;
 
 	switch (function) {
-	case STM32_COUNT_ENCODER_MODE_1:
+	case COUNTER_FUNCTION_INCREASE:
+		/* counts on internal clock when CEN=1 */
+		*action = COUNTER_SYNAPSE_ACTION_NONE;
+		return 0;
+	case COUNTER_FUNCTION_QUADRATURE_X2_A:
 		/* counts up/down on TI1FP1 edge depending on TI2FP2 level */
 		if (synapse->signal->id == count->synapses[0].signal->id)
-			*action = STM32_SYNAPSE_ACTION_BOTH_EDGES;
-		break;
-	case STM32_COUNT_ENCODER_MODE_2:
+			*action = COUNTER_SYNAPSE_ACTION_BOTH_EDGES;
+		else
+			*action = COUNTER_SYNAPSE_ACTION_NONE;
+		return 0;
+	case COUNTER_FUNCTION_QUADRATURE_X2_B:
 		/* counts up/down on TI2FP2 edge depending on TI1FP1 level */
 		if (synapse->signal->id == count->synapses[1].signal->id)
-			*action = STM32_SYNAPSE_ACTION_BOTH_EDGES;
-		break;
-	case STM32_COUNT_ENCODER_MODE_3:
+			*action = COUNTER_SYNAPSE_ACTION_BOTH_EDGES;
+		else
+			*action = COUNTER_SYNAPSE_ACTION_NONE;
+		return 0;
+	case COUNTER_FUNCTION_QUADRATURE_X4:
 		/* counts up/down on both TI1FP1 and TI2FP2 edges */
-		*action = STM32_SYNAPSE_ACTION_BOTH_EDGES;
-		break;
+		*action = COUNTER_SYNAPSE_ACTION_BOTH_EDGES;
+		return 0;
+	default:
+		return -EINVAL;
 	}
-
-	return 0;
 }
 
 static const struct counter_ops stm32_timer_cnt_ops = {
 	.count_read = stm32_count_read,
 	.count_write = stm32_count_write,
-	.function_get = stm32_count_function_get,
-	.function_set = stm32_count_function_set,
-	.action_get = stm32_action_get,
+	.function_read = stm32_count_function_read,
+	.function_write = stm32_count_function_write,
+	.action_read = stm32_action_read,
 };
 
 static struct counter_signal stm32_signals[] = {
@@ -337,31 +316,87 @@ static int stm32_timer_cnt_probe(struct platform_device *pdev)
 	struct stm32_timers *ddata = dev_get_drvdata(pdev->dev.parent);
 	struct device *dev = &pdev->dev;
 	struct stm32_timer_cnt *priv;
+	struct counter_device *counter;
+	int ret;
 
 	if (IS_ERR_OR_NULL(ddata))
 		return -EINVAL;
 
-	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
-	if (!priv)
+	counter = devm_counter_alloc(dev, sizeof(*priv));
+	if (!counter)
 		return -ENOMEM;
 
+	priv = counter_priv(counter);
+
 	priv->regmap = ddata->regmap;
 	priv->clk = ddata->clk;
-	priv->ceiling = ddata->max_arr;
+	priv->max_arr = ddata->max_arr;
+
+	counter->name = dev_name(dev);
+	counter->parent = dev;
+	counter->ops = &stm32_timer_cnt_ops;
+	counter->counts = &stm32_counts;
+	counter->num_counts = 1;
+	counter->signals = stm32_signals;
+	counter->num_signals = ARRAY_SIZE(stm32_signals);
 
-	priv->counter.name = dev_name(dev);
-	priv->counter.parent = dev;
-	priv->counter.ops = &stm32_timer_cnt_ops;
-	priv->counter.counts = &stm32_counts;
-	priv->counter.num_counts = 1;
-	priv->counter.signals = stm32_signals;
-	priv->counter.num_signals = ARRAY_SIZE(stm32_signals);
-	priv->counter.priv = priv;
+	platform_set_drvdata(pdev, priv);
 
 	/* Register Counter device */
-	return devm_counter_register(dev, &priv->counter);
+	ret = devm_counter_add(dev, counter);
+	if (ret < 0)
+		dev_err_probe(dev, ret, "Failed to add counter\n");
+
+	return ret;
 }
 
+static int __maybe_unused stm32_timer_cnt_suspend(struct device *dev)
+{
+	struct stm32_timer_cnt *priv = dev_get_drvdata(dev);
+
+	/* Only take care of enabled counter: don't disturb other MFD child */
+	if (priv->enabled) {
+		/* Backup registers that may get lost in low power mode */
+		regmap_read(priv->regmap, TIM_SMCR, &priv->bak.smcr);
+		regmap_read(priv->regmap, TIM_ARR, &priv->bak.arr);
+		regmap_read(priv->regmap, TIM_CNT, &priv->bak.cnt);
+		regmap_read(priv->regmap, TIM_CR1, &priv->bak.cr1);
+
+		/* Disable the counter */
+		regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, 0);
+		clk_disable(priv->clk);
+	}
+
+	return pinctrl_pm_select_sleep_state(dev);
+}
+
+static int __maybe_unused stm32_timer_cnt_resume(struct device *dev)
+{
+	struct stm32_timer_cnt *priv = dev_get_drvdata(dev);
+	int ret;
+
+	ret = pinctrl_pm_select_default_state(dev);
+	if (ret)
+		return ret;
+
+	if (priv->enabled) {
+		clk_enable(priv->clk);
+
+		/* Restore registers that may have been lost */
+		regmap_write(priv->regmap, TIM_SMCR, priv->bak.smcr);
+		regmap_write(priv->regmap, TIM_ARR, priv->bak.arr);
+		regmap_write(priv->regmap, TIM_CNT, priv->bak.cnt);
+
+		/* Also re-enables the counter */
+		regmap_write(priv->regmap, TIM_CR1, priv->bak.cr1);
+	}
+
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(stm32_timer_cnt_pm_ops, stm32_timer_cnt_suspend,
+			 stm32_timer_cnt_resume);
+
 static const struct of_device_id stm32_timer_cnt_of_match[] = {
 	{ .compatible = "st,stm32-timer-counter", },
 	{},
@@ -373,6 +408,7 @@ static struct platform_driver stm32_timer_cnt_driver = {
 	.driver = {
 		.name = "stm32-timer-counter",
 		.of_match_table = stm32_timer_cnt_of_match,
+		.pm = &stm32_timer_cnt_pm_ops,
 	},
 };
 module_platform_driver(stm32_timer_cnt_driver);
@@ -381,3 +417,4 @@ MODULE_AUTHOR("Benjamin Gaignard <benjamin.gaignard@st.com>");
 MODULE_ALIAS("platform:stm32-timer-counter");
 MODULE_DESCRIPTION("STMicroelectronics STM32 TIMER counter driver");
 MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(COUNTER);