On Tue, Mar 03, 2026 at 09:05:43AM +0100, Marco Felsch wrote:
> On 26-03-03, Liu Ying wrote:
>> On Mon, Mar 02, 2026 at 05:10:41PM +0100, Marco Felsch wrote:
>>> From: Liu Ying <[email protected]>
>>>
>>> NXP i.MX93 mediamix blk-ctrl contains one DISPLAY_MUX register which
>>> configures parallel display format by using the "PARALLEL_DISP_FORMAT"
>>> field. Add a DRM bridge driver to support the display format configuration.
>>>
>>> Signed-off-by: Liu Ying <[email protected]>
>>> [[email protected]: port to v7.0-rc1]
>>> [[email protected]: add review feedback (Alexander)]
>>> [[email protected]: fix to short Kconfig description (checkpath)]
>>> [[email protected]: use "GPL" instead of "GPL v2" (checkpatch)]
>>> [[email protected]: add bus-width support]
>>> Signed-off-by: Marco Felsch <[email protected]>
>>> ---
>>> drivers/gpu/drm/bridge/imx/Kconfig | 11 ++
>>> drivers/gpu/drm/bridge/imx/Makefile | 1 +
>>> drivers/gpu/drm/bridge/imx/imx93-pdfc.c | 225
>>> ++++++++++++++++++++++++++++++++
>>> 3 files changed, 237 insertions(+)
>>>
>>
>> [...]
>>
>>> +static bool imx93_pdfc_bus_output_fmt_supported(const u32 fmt)
>>
>> As I mentioned in v9, can you drop const?
>> I don't think const is needed.
>
> It makes sense to spot failures early. Albeit this function is very
> small, the fmt shouldn't be changed and therefore needs to be const.
If fmt is a pointer, then I think it makes sense to keep const.
Otherwise, it looks a bit over engineered to have const, since this
function is really small and no one would try to change fmt.
>
> I forgot to add the double space fix though, thanks.
>
>>> +{
>>> + int i;
>>> +
>>> + for (i = 0; i < ARRAY_SIZE(imx93_pdfc_bus_output_fmts); i++) {
>>> + if (imx93_pdfc_bus_output_fmts[i] == fmt)
>>> + return true;
>>> + }
>>> +
>>> + return false;
>>> +}
[...]
>>> +static int imx93_pdfc_bridge_atomic_check(struct drm_bridge *bridge,
>>> + struct drm_bridge_state *bridge_state,
>>> + struct drm_crtc_state *crtc_state,
>>> + struct drm_connector_state
>>> *conn_state)
>>> +{
>>> + struct imx93_pdfc *pdfc = bridge_to_imx93_pdfc(bridge);
>>> + const u32 format = bridge_state->output_bus_cfg.format;
>>
>> Can you drop const?
>
> No because this function is not supposed to change the format. The
> function documentation says: this function can alter the bus_cfg.flags
> bit _not_ the format.
The local variable format is not a pointer, so literally the value of
bridge_state->output_bus_cfg.format cannot be changed through format,
which follows the documentation. So, I think const could be dropped.
>
> Regards,
> Marco
>
>
>
>>
>> --
>> Regards,
>> Liu Ying
>>
>
--
Regards,
Liu Ying
