Quoting Bjorn Andersson (2021-07-24 21:24:31)
> As the Qualcomm DisplayPort driver only supports a single instance of
> the driver the commonly used struct dp_display is kept in a global
> variable. As we introduce additional instances this obviously doesn't
> work.
>
> Replace this with a combination of existing references to adjacent
> objects and drvdata.
>
> Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
> ---
Thanks for removing the global.
> drivers/gpu/drm/msm/dp/dp_display.c | 78 ++++++++++++++---------------
> 1 file changed, 37 insertions(+), 41 deletions(-)
>
> diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
> index 70b319a8fe83..8696b36d30e4 100644
> --- a/drivers/gpu/drm/msm/dp/dp_display.c
> +++ b/drivers/gpu/drm/msm/dp/dp_display.c
> @@ -27,7 +27,6 @@
> #include "dp_audio.h"
> #include "dp_debug.h"
>
> -static struct msm_dp *g_dp_display;
> #define HPD_STRING_SIZE 30
>
> enum {
> @@ -122,6 +121,13 @@ static const struct of_device_id dp_dt_match[] = {
> {}
> };
>
> +static struct dp_display_private *dev_to_dp_display_private(struct device *dev)
> +{
> + struct msm_dp *dp = dev_get_drvdata(dev);
> +
> + return container_of(dp, struct dp_display_private, dp_display);
> +}
> +
> static int dp_add_event(struct dp_display_private *dp_priv, u32 event,
> u32 data, u32 delay)
> {
> @@ -198,14 +204,16 @@ static int dp_display_bind(struct device *dev, struct device *master,
> void *data)
> {
> int rc = 0;
> - struct dp_display_private *dp;
> + struct dp_display_private *dp = dev_to_dp_display_private(dev);
> struct drm_device *drm;
> struct msm_drm_private *priv;
>
> drm = dev_get_drvdata(master);
>
> - dp = container_of(g_dp_display,
> - struct dp_display_private, dp_display);
> + if (!dp) {
How can it be NULL? dev_to_dp_display_private() returns container_of()
pointer so it doesn't look possible.
> + DRM_ERROR("DP driver bind failed. Invalid driver data\n");
> + return -EINVAL;
> + }
>
> dp->dp_display.drm_dev = drm;
> priv = drm->dev_private;
