[PATCH v4 03/12] IIO: hw_consumer: add devm_iio_hw_consumer_alloc

[Arnaud Pouliquen]

On 11/19/2017 01:34 PM, Jonathan Cameron wrote:
> On Thu, 9 Nov 2017 11:12:25 +0100
> Arnaud Pouliquen <arnaud.pouliquen at st.com> wrote:
> 
>> Add devm_iio_hw_consumer_alloc function that calls iio_hw_consumer_free
>> when the device is unbound from the bus.
>> 
>> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen at st.com>
> Hmm.. I normally don't like devm for what is a single use case in
> a driver (for now) but I guess this is generic enough it will have
> additional users reasonably soon.  Hence fine.
> 
> Jonathan
>> ---
>>  drivers/iio/buffer/industrialio-hw-consumer.c | 70 ++++++++++++++++++++++++++-
>>  include/linux/iio/hw-consumer.h               |  2 +
>>  2 files changed, 70 insertions(+), 2 deletions(-)
>> 
>> diff --git a/drivers/iio/buffer/industrialio-hw-consumer.c b/drivers/iio/buffer/industrialio-hw-consumer.c
>> index 7d4d800..e980a79 100644
>> --- a/drivers/iio/buffer/industrialio-hw-consumer.c
>> +++ b/drivers/iio/buffer/industrialio-hw-consumer.c
>> @@ -129,15 +129,81 @@ EXPORT_SYMBOL_GPL(iio_hw_consumer_alloc);
>>   */
>>  void iio_hw_consumer_free(struct iio_hw_consumer *hwc)
>>  {
>> -     struct hw_consumer_buffer *buf;
>> +     struct hw_consumer_buffer *buf, *n;
>>  
>>        iio_channel_release_all(hwc->channels);
>> -     list_for_each_entry(buf, &hwc->buffers, head)
>> +     list_for_each_entry_safe(buf, n, &hwc->buffers, head)
>>                iio_buffer_put(&buf->buffer);
> 
> This looks like an unrelated fix.  Push back into the
> original patch?
Yes, I missed to apply this fix directly in Lars's patch:
[01/12] iio: Add hardware consumer buffer support

Thanks

Arnaud
> 
>>        kfree(hwc);
>>  }
>>  EXPORT_SYMBOL_GPL(iio_hw_consumer_free);
>>  
>> +static void devm_iio_hw_consumer_release(struct device *dev, void *res)
>> +{
>> +     iio_hw_consumer_free(*(struct iio_hw_consumer **)res);
>> +}
>> +
>> +static int devm_iio_hw_consumer_match(struct device *dev, void *res, void *data)
>> +{
>> +     struct iio_hw_consumer **r = res;
>> +
>> +     if (!r || !*r) {
>> +             WARN_ON(!r || !*r);
>> +             return 0;
>> +     }
>> +     return *r == data;
>> +}
>> +
>> +/**
>> + * devm_iio_hw_consumer_alloc - Resource-managed iio_hw_consumer_alloc()
>> + * @dev: Pointer to consumer device.
>> + *
>> + * Managed iio_hw_consumer_alloc. iio_hw_consumer allocated with this function
>> + * is automatically freed on driver detach.
>> + *
>> + * If an iio_hw_consumer allocated with this function needs to be freed
>> + * separately, devm_iio_hw_consumer_free() must be used.
>> + *
>> + * returns pointer to allocated iio_hw_consumer on success, NULL on failure.
>> + */
>> +struct iio_hw_consumer *devm_iio_hw_consumer_alloc(struct device *dev)
>> +{
>> +     struct iio_hw_consumer **ptr, *iio_hwc;
>> +
>> +     ptr = devres_alloc(devm_iio_hw_consumer_release, sizeof(*ptr),
>> +                        GFP_KERNEL);
>> +     if (!ptr)
>> +             return NULL;
>> +
>> +     iio_hwc = iio_hw_consumer_alloc(dev);
>> +     if (IS_ERR(iio_hwc)) {
>> +             devres_free(ptr);
>> +     } else {
>> +             *ptr = iio_hwc;
>> +             devres_add(dev, ptr);
>> +     }
>> +
>> +     return iio_hwc;
>> +}
>> +EXPORT_SYMBOL_GPL(devm_iio_hw_consumer_alloc);
>> +
>> +/**
>> + * devm_iio_hw_consumer_free - Resource-managed iio_hw_consumer_free()
>> + * @dev: Pointer to consumer device.
>> + * @hwc: iio_hw_consumer to free.
>> + *
>> + * Free iio_hw_consumer allocated with devm_iio_hw_consumer_alloc().
>> + */
>> +void devm_iio_hw_consumer_free(struct device *dev, struct iio_hw_consumer *hwc)
>> +{
>> +     int rc;
>> +
>> +     rc = devres_release(dev, devm_iio_hw_consumer_release,
>> +                         devm_iio_hw_consumer_match, hwc);
>> +     WARN_ON(rc);
>> +}
>> +EXPORT_SYMBOL_GPL(devm_iio_hw_consumer_free);
>> +
>>  /**
>>   * iio_hw_consumer_enable() - Enable IIO hardware consumer
>>   * @hwc: iio_hw_consumer to enable.
>> diff --git a/include/linux/iio/hw-consumer.h b/include/linux/iio/hw-consumer.h
>> index f16791b..90ecfce 100644
>> --- a/include/linux/iio/hw-consumer.h
>> +++ b/include/linux/iio/hw-consumer.h
>> @@ -14,6 +14,8 @@ struct iio_hw_consumer;
>>  
>>  struct iio_hw_consumer *iio_hw_consumer_alloc(struct device *dev);
>>  void iio_hw_consumer_free(struct iio_hw_consumer *hwc);
>> +struct iio_hw_consumer *devm_iio_hw_consumer_alloc(struct device *dev);
>> +void devm_iio_hw_consumer_free(struct device *dev, struct iio_hw_consumer *hwc);
>>  int iio_hw_consumer_enable(struct iio_hw_consumer *hwc);
>>  void iio_hw_consumer_disable(struct iio_hw_consumer *hwc);
>>  
>