On Thu, May 16, 2024 at 06:10:06PM +0800, Liu Ying wrote:
> Commit f3d9683346d6 ("drm/bridge: adv7511: Allow IRQ to share GPIO pins")
> fails to consider the case where adv7511->i2c_main->irq is zero, i.e.,
> no interrupt requested at all.
>
> Without interrupt, adv7511_wait_for_edid() could return -EIO sometimes,
> because it polls adv7511->edid_read flag by calling adv7511_irq_process()
> a few times, but adv7511_irq_process() happens to refuse to handle
> interrupt by returning -ENODATA. Hence, EDID retrieval fails randomly.
>
> Fix the issue by checking adv7511->i2c_main->irq before exiting interrupt
> handling from adv7511_irq_process().
>
> Fixes: f3d9683346d6 ("drm/bridge: adv7511: Allow IRQ to share GPIO pins")
> Signed-off-by: Liu Ying <victor.liu@xxxxxxx>
> ---
> drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
> index 6089b0bb9321..2074fa3c1b7b 100644
> --- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
> +++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
> @@ -479,7 +479,8 @@ static int adv7511_irq_process(struct adv7511 *adv7511, bool process_hpd)
> return ret;
>
> /* If there is no IRQ to handle, exit indicating no IRQ data */
> - if (!(irq0 & (ADV7511_INT0_HPD | ADV7511_INT0_EDID_READY)) &&
> + if (adv7511->i2c_main->irq &&
> + !(irq0 & (ADV7511_INT0_HPD | ADV7511_INT0_EDID_READY)) &&
> !(irq1 & ADV7511_INT1_DDC_ERROR))
> return -ENODATA;
I think it might be better to handle -ENODATA in adv7511_wait_for_edid()
instead. WDYT?
--
With best wishes
Dmitry
