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

From: Guenter Roeck
Date: Tue Dec 26 2017 - 12:24:51 EST


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@xxxxxxxxx>

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);
>