[v3,2/2] hwmon: (aspeed-pwm-tacho) Deassert reset in probe

Message ID 20171223130528.5346-3-joel@jms.id.au
State Accepted
Commit 18c514cc0e0278b7852a6741973a9523ad012700
Headers show
Series
  • hwmon: Add reset support to aspeed-pwm-tach
Related show

Commit Message

Joel Stanley Dec. 23, 2017, 1:05 p.m.
The ASPEED SoC must deassert a reset in order to use the PWM/tach
peripheral.

Signed-off-by: Joel Stanley <joel@jms.id.au>

---
 drivers/hwmon/aspeed-pwm-tacho.c | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

-- 
2.15.1

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Comments

Guenter Roeck Dec. 26, 2017, 5:24 p.m. | #1
On Sat, Dec 23, 2017 at 11:35:28PM +1030, Joel wrote:
> The ASPEED SoC must deassert a reset in order to use the PWM/tach

> peripheral.

> 

> Signed-off-by: Joel Stanley <joel@jms.id.au>


Applied to hwmon-next.

Thanks,
Guenter

> ---

>  drivers/hwmon/aspeed-pwm-tacho.c | 22 ++++++++++++++++++++++

>  1 file changed, 22 insertions(+)

> 

> diff --git a/drivers/hwmon/aspeed-pwm-tacho.c b/drivers/hwmon/aspeed-pwm-tacho.c

> index 63a95e23ca81..693a3d53cab5 100644

> --- a/drivers/hwmon/aspeed-pwm-tacho.c

> +++ b/drivers/hwmon/aspeed-pwm-tacho.c

> @@ -19,6 +19,7 @@

>  #include <linux/of_platform.h>

>  #include <linux/platform_device.h>

>  #include <linux/regmap.h>

> +#include <linux/reset.h>

>  #include <linux/sysfs.h>

>  #include <linux/thermal.h>

>  

> @@ -181,6 +182,7 @@ struct aspeed_cooling_device {

>  

>  struct aspeed_pwm_tacho_data {

>  	struct regmap *regmap;

> +	struct reset_control *rst;

>  	unsigned long clk_freq;

>  	bool pwm_present[8];

>  	bool fan_tach_present[16];

> @@ -905,6 +907,13 @@ static int aspeed_create_fan(struct device *dev,

>  	return 0;

>  }

>  

> +static void aspeed_pwm_tacho_remove(void *data)

> +{

> +	struct aspeed_pwm_tacho_data *priv = data;

> +

> +	reset_control_assert(priv->rst);

> +}

> +

>  static int aspeed_pwm_tacho_probe(struct platform_device *pdev)

>  {

>  	struct device *dev = &pdev->dev;

> @@ -931,6 +940,19 @@ static int aspeed_pwm_tacho_probe(struct platform_device *pdev)

>  			&aspeed_pwm_tacho_regmap_config);

>  	if (IS_ERR(priv->regmap))

>  		return PTR_ERR(priv->regmap);

> +

> +	priv->rst = devm_reset_control_get_exclusive(dev, NULL);

> +	if (IS_ERR(priv->rst)) {

> +		dev_err(dev,

> +			"missing or invalid reset controller device tree entry");

> +		return PTR_ERR(priv->rst);

> +	}

> +	reset_control_deassert(priv->rst);

> +

> +	ret = devm_add_action_or_reset(dev, aspeed_pwm_tacho_remove, priv);

> +	if (ret)

> +		return ret;

> +

>  	regmap_write(priv->regmap, ASPEED_PTCR_TACH_SOURCE, 0);

>  	regmap_write(priv->regmap, ASPEED_PTCR_TACH_SOURCE_EXT, 0);

>  

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Patch

diff --git a/drivers/hwmon/aspeed-pwm-tacho.c b/drivers/hwmon/aspeed-pwm-tacho.c
index 63a95e23ca81..693a3d53cab5 100644
--- a/drivers/hwmon/aspeed-pwm-tacho.c
+++ b/drivers/hwmon/aspeed-pwm-tacho.c
@@ -19,6 +19,7 @@ 
 #include <linux/of_platform.h>
 #include <linux/platform_device.h>
 #include <linux/regmap.h>
+#include <linux/reset.h>
 #include <linux/sysfs.h>
 #include <linux/thermal.h>
 
@@ -181,6 +182,7 @@  struct aspeed_cooling_device {
 
 struct aspeed_pwm_tacho_data {
 	struct regmap *regmap;
+	struct reset_control *rst;
 	unsigned long clk_freq;
 	bool pwm_present[8];
 	bool fan_tach_present[16];
@@ -905,6 +907,13 @@  static int aspeed_create_fan(struct device *dev,
 	return 0;
 }
 
+static void aspeed_pwm_tacho_remove(void *data)
+{
+	struct aspeed_pwm_tacho_data *priv = data;
+
+	reset_control_assert(priv->rst);
+}
+
 static int aspeed_pwm_tacho_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
@@ -931,6 +940,19 @@  static int aspeed_pwm_tacho_probe(struct platform_device *pdev)
 			&aspeed_pwm_tacho_regmap_config);
 	if (IS_ERR(priv->regmap))
 		return PTR_ERR(priv->regmap);
+
+	priv->rst = devm_reset_control_get_exclusive(dev, NULL);
+	if (IS_ERR(priv->rst)) {
+		dev_err(dev,
+			"missing or invalid reset controller device tree entry");
+		return PTR_ERR(priv->rst);
+	}
+	reset_control_deassert(priv->rst);
+
+	ret = devm_add_action_or_reset(dev, aspeed_pwm_tacho_remove, priv);
+	if (ret)
+		return ret;
+
 	regmap_write(priv->regmap, ASPEED_PTCR_TACH_SOURCE, 0);
 	regmap_write(priv->regmap, ASPEED_PTCR_TACH_SOURCE_EXT, 0);