[PATCH v7 03/14] ASoC: Intel: catpt: Add IPC message handlers

Andy Shevchenko andriy.shevchenko at linux.intel.com
Mon Sep 21 16:20:12 CEST 2020


On Mon, Sep 21, 2020 at 03:58:33PM +0200, Amadeusz Sławiński wrote:
> On 9/21/2020 2:59 PM, Andy Shevchenko wrote:
> > > +struct catpt_set_volume_input {
> > > +	u32 channel;
> > > +	u32 target_volume;
> > > +	u64 curve_duration;
> > > +	enum catpt_audio_curve_type curve_type __aligned(4);
> > > +} __packed;
> > How this __packed changes anything? In general __packed doesn't make sense for
> > in-kernel data structures. Otherwise you have to use proper (POD) types for
> > data. Ditto for all similar cases.
> 
> All of __packed use in code is done on structures used to communicate with
> FW, which is binary interface, so it is not kernel only structure, as it is
> also FW one. While we can expect compiler to do the right thing, I consider
> it is better to be explicit about what kind of data we are handling, so
> there aren't any surprises.

Size of enum is compiler defined. It may not be used in the ABIs.

__uXX vs. uXX I dunno.

-- 
With Best Regards,
Andy Shevchenko




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