1 files changed, 51 insertions, 127 deletions

diff --git a/drivers/pwm/pwm-cros-ec.c b/drivers/pwm/pwm-cros-ec.c
index 86df6702cb83..67cfa17f58e0 100644
--- a/drivers/pwm/pwm-cros-ec.c
+++ b/drivers/pwm/pwm-cros-ec.c
@@ -6,6 +6,7 @@
  */
 
 #include <linux/module.h>
+#include <linux/of.h>
 #include <linux/platform_data/cros_ec_commands.h>
 #include <linux/platform_data/cros_ec_proto.h>
 #include <linux/platform_device.h>
@@ -17,49 +18,17 @@
 /**
  * struct cros_ec_pwm_device - Driver data for EC PWM
  *
- * @dev: Device node
  * @ec: Pointer to EC device
- * @chip: PWM controller chip
  * @use_pwm_type: Use PWM types instead of generic channels
  */
 struct cros_ec_pwm_device {
-	struct device *dev;
 	struct cros_ec_device *ec;
-	struct pwm_chip chip;
 	bool use_pwm_type;
 };
 
-/**
- * struct cros_ec_pwm - per-PWM driver data
- * @duty_cycle: cached duty cycle
- */
-struct cros_ec_pwm {
-	u16 duty_cycle;
-};
-
-static inline struct cros_ec_pwm_device *pwm_to_cros_ec_pwm(struct pwm_chip *c)
-{
-	return container_of(c, struct cros_ec_pwm_device, chip);
-}
-
-static int cros_ec_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
+static inline struct cros_ec_pwm_device *pwm_to_cros_ec_pwm(struct pwm_chip *chip)
 {
-	struct cros_ec_pwm *channel;
-
-	channel = kzalloc(sizeof(*channel), GFP_KERNEL);
-	if (!channel)
-		return -ENOMEM;
-
-	pwm_set_chip_data(pwm, channel);
-
-	return 0;
-}
-
-static void cros_ec_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
-{
-	struct cros_ec_pwm *channel = pwm_get_chip_data(pwm);
-
-	kfree(channel);
+	return pwmchip_get_drvdata(chip);
 }
 
 static int cros_ec_dt_type_to_pwm_type(u8 dt_index, u8 *pwm_type)
@@ -80,10 +49,9 @@ static int cros_ec_pwm_set_duty(struct cros_ec_pwm_device *ec_pwm, u8 index,
 				u16 duty)
 {
 	struct cros_ec_device *ec = ec_pwm->ec;
-	struct {
-		struct cros_ec_command msg;
+	TRAILING_OVERLAP(struct cros_ec_command, msg, data,
 		struct ec_params_pwm_set_duty params;
-	} __packed buf;
+	) __packed buf;
 	struct ec_params_pwm_set_duty *params = &buf.params;
 	struct cros_ec_command *msg = &buf.msg;
 	int ret;
@@ -112,16 +80,14 @@ static int cros_ec_pwm_set_duty(struct cros_ec_pwm_device *ec_pwm, u8 index,
 	return cros_ec_cmd_xfer_status(ec, msg);
 }
 
-static int cros_ec_pwm_get_duty(struct cros_ec_pwm_device *ec_pwm, u8 index)
+static int cros_ec_pwm_get_duty(struct cros_ec_device *ec, bool use_pwm_type, u8 index)
 {
-	struct cros_ec_device *ec = ec_pwm->ec;
-	struct {
-		struct cros_ec_command msg;
+	TRAILING_OVERLAP(struct cros_ec_command, msg, data,
 		union {
 			struct ec_params_pwm_get_duty params;
 			struct ec_response_pwm_get_duty resp;
 		};
-	} __packed buf;
+	) __packed buf;
 	struct ec_params_pwm_get_duty *params = &buf.params;
 	struct ec_response_pwm_get_duty *resp = &buf.resp;
 	struct cros_ec_command *msg = &buf.msg;
@@ -134,7 +100,7 @@ static int cros_ec_pwm_get_duty(struct cros_ec_pwm_device *ec_pwm, u8 index)
 	msg->insize = sizeof(*resp);
 	msg->outsize = sizeof(*params);
 
-	if (ec_pwm->use_pwm_type) {
+	if (use_pwm_type) {
 		ret = cros_ec_dt_type_to_pwm_type(index, &params->pwm_type);
 		if (ret) {
 			dev_err(ec->dev, "Invalid PWM type index: %d\n", index);
@@ -157,7 +123,6 @@ static int cros_ec_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
 			     const struct pwm_state *state)
 {
 	struct cros_ec_pwm_device *ec_pwm = pwm_to_cros_ec_pwm(chip);
-	struct cros_ec_pwm *channel = pwm_get_chip_data(pwm);
 	u16 duty_cycle;
 	int ret;
 
@@ -178,8 +143,6 @@ static int cros_ec_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
 	if (ret < 0)
 		return ret;
 
-	channel->duty_cycle = state->duty_cycle;
-
 	return 0;
 }
 
@@ -187,59 +150,25 @@ static int cros_ec_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
 				 struct pwm_state *state)
 {
 	struct cros_ec_pwm_device *ec_pwm = pwm_to_cros_ec_pwm(chip);
-	struct cros_ec_pwm *channel = pwm_get_chip_data(pwm);
 	int ret;
 
-	ret = cros_ec_pwm_get_duty(ec_pwm, pwm->hwpwm);
+	ret = cros_ec_pwm_get_duty(ec_pwm->ec, ec_pwm->use_pwm_type, pwm->hwpwm);
 	if (ret < 0) {
-		dev_err(chip->dev, "error getting initial duty: %d\n", ret);
+		dev_err(pwmchip_parent(chip), "error getting initial duty: %d\n", ret);
 		return ret;
 	}
 
 	state->enabled = (ret > 0);
+	state->duty_cycle = ret;
 	state->period = EC_PWM_MAX_DUTY;
-
-	/*
-	 * Note that "disabled" and "duty cycle == 0" are treated the same. If
-	 * the cached duty cycle is not zero, used the cached duty cycle. This
-	 * ensures that the configured duty cycle is kept across a disable and
-	 * enable operation and avoids potentially confusing consumers.
-	 *
-	 * For the case of the initial hardware readout, channel->duty_cycle
-	 * will be 0 and the actual duty cycle read from the EC is used.
-	 */
-	if (ret == 0 && channel->duty_cycle > 0)
-		state->duty_cycle = channel->duty_cycle;
-	else
-		state->duty_cycle = ret;
+	state->polarity = PWM_POLARITY_NORMAL;
 
 	return 0;
 }
 
-static struct pwm_device *
-cros_ec_pwm_xlate(struct pwm_chip *pc, const struct of_phandle_args *args)
-{
-	struct pwm_device *pwm;
-
-	if (args->args[0] >= pc->npwm)
-		return ERR_PTR(-EINVAL);
-
-	pwm = pwm_request_from_chip(pc, args->args[0], NULL);
-	if (IS_ERR(pwm))
-		return pwm;
-
-	/* The EC won't let us change the period */
-	pwm->args.period = EC_PWM_MAX_DUTY;
-
-	return pwm;
-}
-
 static const struct pwm_ops cros_ec_pwm_ops = {
-	.request = cros_ec_pwm_request,
-	.free = cros_ec_pwm_free,
 	.get_state	= cros_ec_pwm_get_state,
 	.apply		= cros_ec_pwm_apply,
-	.owner		= THIS_MODULE,
 };
 
 /*
@@ -247,13 +176,17 @@ static const struct pwm_ops cros_ec_pwm_ops = {
  * of PWMs it supports directly, so we have to read the pwm duty cycle for
  * subsequent channels until we get an error.
  */
-static int cros_ec_num_pwms(struct cros_ec_pwm_device *ec_pwm)
+static int cros_ec_num_pwms(struct cros_ec_device *ec)
 {
 	int i, ret;
 
 	/* The index field is only 8 bits */
 	for (i = 0; i <= U8_MAX; i++) {
-		ret = cros_ec_pwm_get_duty(ec_pwm, i);
+		/*
+		 * Note that this function is only called when use_pwm_type is
+		 * false. With use_pwm_type == true the number of PWMs is fixed.
+		 */
+		ret = cros_ec_pwm_get_duty(ec, false, i);
 		/*
 		 * We look for SUCCESS, INVALID_COMMAND, or INVALID_PARAM
 		 * responses; everything else is treated as an error.
@@ -282,58 +215,50 @@ static int cros_ec_pwm_probe(struct platform_device *pdev)
 	struct device_node *np = pdev->dev.of_node;
 	struct cros_ec_pwm_device *ec_pwm;
 	struct pwm_chip *chip;
+	bool use_pwm_type = false;
+	unsigned int i, npwm;
 	int ret;
 
-	if (!ec) {
-		dev_err(dev, "no parent EC device\n");
-		return -EINVAL;
+	if (!ec)
+		return dev_err_probe(dev, -EINVAL, "no parent EC device\n");
+
+	if (of_device_is_compatible(np, "google,cros-ec-pwm-type")) {
+		use_pwm_type = true;
+		npwm = CROS_EC_PWM_DT_COUNT;
+	} else {
+		ret = cros_ec_num_pwms(ec);
+		if (ret < 0)
+			return dev_err_probe(dev, ret, "Couldn't find PWMs\n");
+		npwm = ret;
 	}
 
-	ec_pwm = devm_kzalloc(dev, sizeof(*ec_pwm), GFP_KERNEL);
-	if (!ec_pwm)
-		return -ENOMEM;
-	chip = &ec_pwm->chip;
-	ec_pwm->ec = ec;
+	chip = devm_pwmchip_alloc(dev, npwm, sizeof(*ec_pwm));
+	if (IS_ERR(chip))
+		return PTR_ERR(chip);
 
-	if (of_device_is_compatible(np, "google,cros-ec-pwm-type"))
-		ec_pwm->use_pwm_type = true;
+	ec_pwm = pwm_to_cros_ec_pwm(chip);
+	ec_pwm->use_pwm_type = use_pwm_type;
+	ec_pwm->ec = ec;
 
 	/* PWM chip */
-	chip->dev = dev;
 	chip->ops = &cros_ec_pwm_ops;
-	chip->of_xlate = cros_ec_pwm_xlate;
-	chip->of_pwm_n_cells = 1;
 
-	if (ec_pwm->use_pwm_type) {
-		chip->npwm = CROS_EC_PWM_DT_COUNT;
-	} else {
-		ret = cros_ec_num_pwms(ec_pwm);
-		if (ret < 0) {
-			dev_err(dev, "Couldn't find PWMs: %d\n", ret);
-			return ret;
-		}
-		chip->npwm = ret;
-	}
+	/*
+	 * The device tree binding for this device is special as it only uses a
+	 * single cell (for the hwid) and so doesn't provide a default period.
+	 * This isn't a big problem though as the hardware only supports a
+	 * single period length, it's just a bit ugly to make this fit into the
+	 * pwm core abstractions. So initialize the period here, as
+	 * of_pwm_xlate_with_flags() won't do that for us.
+	 */
+	for (i = 0; i < npwm; ++i)
+		chip->pwms[i].args.period = EC_PWM_MAX_DUTY;
 
 	dev_dbg(dev, "Probed %u PWMs\n", chip->npwm);
 
-	ret = pwmchip_add(chip);
-	if (ret < 0) {
-		dev_err(dev, "cannot register PWM: %d\n", ret);
-		return ret;
-	}
-
-	platform_set_drvdata(pdev, ec_pwm);
-
-	return ret;
-}
-
-static int cros_ec_pwm_remove(struct platform_device *dev)
-{
-	struct cros_ec_pwm_device *ec_pwm = platform_get_drvdata(dev);
-	struct pwm_chip *chip = &ec_pwm->chip;
-
-	pwmchip_remove(chip);
+	ret = devm_pwmchip_add(dev, chip);
+	if (ret < 0)
+		return dev_err_probe(dev, ret, "cannot register PWM\n");
 
 	return 0;
 }
@@ -349,7 +274,6 @@ MODULE_DEVICE_TABLE(of, cros_ec_pwm_of_match);
 
 static struct platform_driver cros_ec_pwm_driver = {
 	.probe = cros_ec_pwm_probe,
-	.remove = cros_ec_pwm_remove,
 	.driver = {
 		.name = "cros-ec-pwm",
 		.of_match_table = of_match_ptr(cros_ec_pwm_of_match),