On Fri, 24 Nov 2017 15:52:26 +0100 Arnaud Pouliquen <arnaud.pouliquen@xxxxxx> wrote: > On 11/19/2017 03:18 PM, Jonathan Cameron wrote: > > On Thu, 9 Nov 2017 11:12:31 +0100 > > Arnaud Pouliquen <arnaud.pouliquen@xxxxxx> wrote: > > > >> This code offers a way to handle PDM audio microphones in > >> ASOC framework. Audio driver should use consumer API. > >> A specific management is implemented for DMA, with a > >> callback, to allows to handle audio buffers efficiently. > >> > >> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@xxxxxx> > > > > A few minor points inline. I'm not sure I really 'like' the > > solution we've ended up with currently but if it works it will > > do just fine for now :) > > > > Jonathan > > > > > >> --- > >> V3 -> V4 changes: > >> - Merge audio implementation in stm32-dfsdm-adc.c instead of creating separate file > >> - Add sysfs document for exported attributes > >> > >> .../ABI/testing/sysfs-bus-iio-dfsdm-adc-stm32 | 22 + > >> drivers/iio/adc/stm32-dfsdm-adc.c | 517 ++++++++++++++++++++- > >> include/linux/iio/adc/stm32-dfsdm-adc.h | 27 ++ > >> 3 files changed, 562 insertions(+), 4 deletions(-) > >> create mode 100644 Documentation/ABI/testing/sysfs-bus-iio-dfsdm-adc-stm32 > >> create mode 100644 include/linux/iio/adc/stm32-dfsdm-adc.h > >> > >> diff --git a/Documentation/ABI/testing/sysfs-bus-iio-dfsdm-adc-stm32 b/Documentation/ABI/testing/sysfs-bus-iio-dfsdm-adc-stm32 > >> new file mode 100644 > >> index 0000000..0ce5508 > >> --- /dev/null > >> +++ b/Documentation/ABI/testing/sysfs-bus-iio-dfsdm-adc-stm32 > >> @@ -0,0 +1,22 @@ > >> +What: /sys/bus/iio/devices/iio:deviceX/in_voltage_audio_sampling_rate > >> +KernelVersion: 4.14 > >> +Contact: arnaud.pouliquen@xxxxxx > >> +Description: > >> + For audio purpose only. > >> + Used by audio driver to set/get the audio sampling rate. > >> + Reading returns current audio sample frequency. > >> + Writing value before starting conversions. > > > > I would like to see a note here on why sampling_frequency can't be used for > > this purpose. > The IIO_CHAN_INFO_SAMP_FREQ can not be used because consumer API allows > only to access to ext_info attributes. > An alternate is to export channel attribute functions the consumer API. > - iio_read_channel_attribute (already exist) > - iio_write_channel_attribute Yes - add these please. Just not been a usecase before for the general write. > > Please, tell me your preference. <snip> > >> +/** > >> + * stm32_dfsdm_get_buff_cb - register a callback > >> + * that will be called when DMA transfer period is achieved. > > Please run kernel-doc over this file. I'm fairly sure this isn't > > quite meeting the spec... > Sorry it is not crystal clear for me, could you detail what you would > mean by > "I'm fairly sure this isn't quite meeting the spec.."? I don't think it lets you have multiple lines for the short description IIRC. Not sure about the indented function parameters.. Might be new since I last looked! > > > > >> + * > >> + * @iio_dev: Handle to IIO device. > >> + * @cb: pointer to callback function. > >> + * @data: pointer to data buffer > >> + * @size: size in byte of the data buffer > >> + * @private: pointer to consumer private structure > >> + * @private: pointer to consumer private structure > >> + */ -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
