Hi Ondrej, On Tue, Jul 14, 2020 at 12:23:01PM +0200, Ondrej Jirman wrote: > Make enable-gpio optional to allow using this driver with boards that > have vibrator connected to a power supply without intermediate gpio > based enable circuitry. > > Also avoid a case where neither regulator nor enable gpio is specified, > and bail out in probe in such a case. > > Signed-off-by: Ondrej Jirman <megous@xxxxxxxxxx> > --- > drivers/input/misc/gpio-vibra.c | 14 ++++++++++---- > 1 file changed, 10 insertions(+), 4 deletions(-) > > diff --git a/drivers/input/misc/gpio-vibra.c b/drivers/input/misc/gpio-vibra.c > index f79f75595dd7..b3bb7e61ed1d 100644 > --- a/drivers/input/misc/gpio-vibra.c > +++ b/drivers/input/misc/gpio-vibra.c > @@ -39,7 +39,7 @@ static int gpio_vibrator_start(struct gpio_vibrator *vibrator) > struct device *pdev = vibrator->input->dev.parent; > int err; > > - if (!vibrator->vcc_on) { > + if (vibrator->vcc && !vibrator->vcc_on) { > err = regulator_enable(vibrator->vcc); > if (err) { > dev_err(pdev, "failed to enable regulator: %d\n", err); > @@ -57,7 +57,7 @@ static void gpio_vibrator_stop(struct gpio_vibrator *vibrator) > { > gpiod_set_value_cansleep(vibrator->gpio, 0); > > - if (vibrator->vcc_on) { > + if (vibrator->vcc && vibrator->vcc_on) { > regulator_disable(vibrator->vcc); > vibrator->vcc_on = false; > } > @@ -112,7 +112,7 @@ static int gpio_vibrator_probe(struct platform_device *pdev) > if (!vibrator->input) > return -ENOMEM; > > - vibrator->vcc = devm_regulator_get(&pdev->dev, "vcc"); > + vibrator->vcc = devm_regulator_get_optional(&pdev->dev, "vcc"); I know it is very surprising, but regulator_get_optional does not return NULL when regulator is not present, but rather ERR_PTR(-ENODEV). You need to replace it with NULL in the branch below, or change conditions to !IS_ERR(virbrator->vcc) (and still handle -ENODEV in the branch below). > err = PTR_ERR_OR_ZERO(vibrator->vcc); > if (err) { > if (err != -EPROBE_DEFER) > @@ -121,7 +121,8 @@ static int gpio_vibrator_probe(struct platform_device *pdev) > return err; > } > > - vibrator->gpio = devm_gpiod_get(&pdev->dev, "enable", GPIOD_OUT_LOW); > + vibrator->gpio = devm_gpiod_get_optional(&pdev->dev, "enable", > + GPIOD_OUT_LOW); > err = PTR_ERR_OR_ZERO(vibrator->gpio); > if (err) { > if (err != -EPROBE_DEFER) > @@ -130,6 +131,11 @@ static int gpio_vibrator_probe(struct platform_device *pdev) > return err; > } > > + if (!vibrator->vcc && !vibrator->gpio) { > + dev_err(&pdev->dev, "Neither gpio nor regulator provided\n"); > + return -EINVAL; > + } > + > INIT_WORK(&vibrator->play_work, gpio_vibrator_play_work); > > vibrator->input->name = "gpio-vibrator"; > -- > 2.27.0 > Thanks. -- Dmitry