Hi Guenter,
Am 31.01.19 um 18:56 schrieb Guenter Roeck:
> On Tue, Jan 29, 2019 at 06:07:11PM +0100, Stefan Wahren wrote:
>> This adds optional regulator support to the pwm-fan driver. This is
>> necessary for pwm fans which are powered by a switchable supply.
>>
>> Signed-off-by: Stefan Wahren <stefan.wahren@xxxxxxxx>
>> ---
>> drivers/hwmon/pwm-fan.c | 35 +++++++++++++++++++++++++++++++++++
>> 1 file changed, 35 insertions(+)
>>
>> diff --git a/drivers/hwmon/pwm-fan.c b/drivers/hwmon/pwm-fan.c
>> index 2c94482..9e0591e 100644
>> --- a/drivers/hwmon/pwm-fan.c
>> +++ b/drivers/hwmon/pwm-fan.c
>> @@ -23,6 +23,7 @@
>> #include <linux/of.h>
>> #include <linux/platform_device.h>
>> #include <linux/pwm.h>
>> +#include <linux/regulator/consumer.h>
>> #include <linux/sysfs.h>
>> #include <linux/thermal.h>
>>
>> @@ -31,6 +32,7 @@
>> struct pwm_fan_ctx {
>> struct mutex lock;
>> struct pwm_device *pwm;
>> + struct regulator *reg_en;
>> unsigned int pwm_value;
>> unsigned int pwm_fan_state;
>> unsigned int pwm_fan_max_state;
>> @@ -244,6 +246,23 @@ static int pwm_fan_probe(struct platform_device *pdev)
>> return ret;
>> }
>>
>> + ctx->reg_en = devm_regulator_get_optional(&pdev->dev, "fan");
>> + if (!IS_ERR(ctx->reg_en)) {
> It is customary to handle the error case first.
>
>> + ret = regulator_enable(ctx->reg_en);
>> + if (ret)
>> + dev_err(&pdev->dev,
>> + "Failed to enable fan supply: %d\n", ret);
>> + } else {
>> + switch (PTR_ERR(ctx->reg_en)) {
>> + case -ENODEV:
>> + case -ENOSYS:
> Does devm_regulator_get_optional() ever return -ENOSYS ?
> I glanced through other calls to devm_regulator_get_optional(),
> but I don't see that check anywhere.
sorry, i mixed this up with. In case CONFIG_REGULATOR=n we are getting
-ENODEV.
Thanks Stefan
