[PATCH 15/17] drm/tegra: Fix potential bug on driver unload

[Andrzej Hajda]

Hi Thierry,

Just passing by.

On 11/03/2014 10:27 AM, Thierry Reding wrote:
> From: Thierry Reding <treding at nvidia.com>
> 
> The HDMI hotplug signal may toggle after the DRM driver has been
> unloaded. Make sure not to call into DRM if that's the case.
> 
> Signed-off-by: Thierry Reding <treding at nvidia.com>
> ---
>  drivers/gpu/drm/tegra/output.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/tegra/output.c b/drivers/gpu/drm/tegra/output.c
> index 6b393cfbb5e7..def74914dd72 100644
> --- a/drivers/gpu/drm/tegra/output.c
> +++ b/drivers/gpu/drm/tegra/output.c
> @@ -181,7 +181,8 @@ static irqreturn_t hpd_irq(int irq, void *data)
>  {
>  	struct tegra_output *output = data;
>  
> -	drm_helper_hpd_irq_event(output->connector.dev);
> +	if (output->connector.dev)
> +		drm_helper_hpd_irq_event(output->connector.dev);
>  
>  	return IRQ_HANDLED;
>  }
> 

Since output->connector.dev is not synchronized between irq and other
code this patch do not solves the issue, it just decreases chances of
the disaster.

Regards
Andrzej