On Wed, Aug 01, 2012 at 04:37:09PM +0900, Alexandre Courbot wrote: > Add resource managed variants of pwm_get() and pwm_put() for > convenience. Code is largely inspired by the equivalent devm functions > of the regulator framework. > > Signed-off-by: Alexandre Courbot <acour...@nvidia.com> > --- > Documentation/driver-model/devres.txt | 4 +++ > Documentation/pwm.txt | 5 +-- > drivers/pwm/core.c | 57 > +++++++++++++++++++++++++++++++++++ > include/linux/pwm.h | 3 ++ > 4 files changed, 67 insertions(+), 2 deletions(-) > > diff --git a/Documentation/driver-model/devres.txt > b/Documentation/driver-model/devres.txt > index 950856b..43cff70 100644 > --- a/Documentation/driver-model/devres.txt > +++ b/Documentation/driver-model/devres.txt > @@ -284,3 +284,7 @@ CLOCK > PINCTRL > devm_pinctrl_get() > devm_pinctrl_put() > + > +PWM > + devm_pwm_get() > + devm_pwm_put() > diff --git a/Documentation/pwm.txt b/Documentation/pwm.txt > index 554290e..4719c12 100644 > --- a/Documentation/pwm.txt > +++ b/Documentation/pwm.txt > @@ -35,8 +35,9 @@ Using PWMs > Legacy users can request a PWM device using pwm_request() and free it > after usage with pwm_free(). > > -New users should use the pwm_get() function and pass to it the consumer > -device or a consumer name. pwm_put() is used to free the PWM device. > +New users should use the pwm_get() or devm_pwm_get() function and pass to it > the > +consumer device or a consumer name. pwm_put() or devm_pwm_put() is used to > free > +the PWM device.
I think I'd prefer the original text with an additional line mentioning
the managed variants.
>
> After being requested a PWM has to be configured using:
>
> diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c
> index ecb7690..5a5e19b 100644
> --- a/drivers/pwm/core.c
> +++ b/drivers/pwm/core.c
> @@ -624,6 +624,63 @@ out:
> }
> EXPORT_SYMBOL_GPL(pwm_put);
>
> +static void devm_pwm_release(struct device *dev, void *res)
> +{
> + pwm_put(*(struct pwm_device **)res);
> +}
> +
> +/**
> + * devm_pwm_get() - Resource managed pwm_get()
This is missing parameter descriptions here.
> + *
> + * This works are pwm_get() but the acquired pwm will automatically be
> released
"works like"? Also "acquired PWM" or "acquired PWM device".
> + * on driver detach. See pwm_get() for more details.
> + */
> +struct pwm_device *devm_pwm_get(struct device *dev, const char *consumer)
> +{
> + struct pwm_device **ptr, *pwm;
> +
> + ptr = devres_alloc(devm_pwm_release, sizeof(**ptr), GFP_KERNEL);
> + if (!ptr)
> + return ERR_PTR(-ENOMEM);
> +
> + pwm = pwm_get(dev, consumer);
> + if (!IS_ERR(pwm)) {
> + *ptr = pwm;
> + devres_add(dev, ptr);
> + } else {
> + devres_free(ptr);
> + }
> +
> + return pwm;
> +}
> +EXPORT_SYMBOL_GPL(devm_pwm_get);
> +
> +static int devm_pwm_match(struct device *dev, void *res, void *data)
> +{
> + struct pwm_device **p = res;
> +
> + if (WARN_ON(!p || !*p))
> + return 0;
> +
> + return *p == data;
> +}
> +
> +/**
> + * devm_pwm_put() - Resource managed pwm_put()
> + *
> + * Releases a pwm previously allocated using devm_pwm_get. Calling this
> function
> + * is usually not needed as the devm-allocated pwm will automatically be
> + * released on driver detach.
> + */
Same comments as for devm_pwm_get().
> +void devm_pwm_put(struct device *dev, struct pwm_device *pwm)
> +{
> + int ret;
> +
> + ret = devres_release(dev, devm_pwm_release, devm_pwm_match, pwm);
> + WARN_ON(ret);
> +}
> +EXPORT_SYMBOL_GPL(devm_pwm_put);
> +
> #ifdef CONFIG_DEBUG_FS
> static void pwm_dbg_show(struct pwm_chip *chip, struct seq_file *s)
> {
> diff --git a/include/linux/pwm.h b/include/linux/pwm.h
> index 21d076c..af9c39a 100644
> --- a/include/linux/pwm.h
> +++ b/include/linux/pwm.h
> @@ -123,7 +123,10 @@ struct pwm_device *pwm_request_from_chip(struct pwm_chip
> *chip,
> const char *label);
>
> struct pwm_device *pwm_get(struct device *dev, const char *consumer);
> +struct pwm_device *devm_pwm_get(struct device *dev, const char *consumer);
> +
> void pwm_put(struct pwm_device *pwm);
> +void devm_pwm_put(struct device *dev, struct pwm_device *pwm);
Can the managed variants be grouped together, please?
Looks good otherwise. Thanks for taking care of it.
Thierry
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