Re: [PATCH v3 2/6] drm: lcdif: Drop unnecessary NULL pointer check on lcdif->bridge

From: Alexander Stein
Date: Tue Feb 14 2023 - 08:55:38 EST


Hi Liu,

thanks for the update.

Am Montag, 13. Februar 2023, 09:56:08 CET schrieb Liu Ying:
> A valid bridge is already found in lcdif_attach_bridge() and set
> to lcdif->bridge, so lcdif->bridge cannot be a NULL pointer. Drop
> the unnecessary NULL pointer check in KMS stage.
>
> Signed-off-by: Liu Ying <victor.liu@xxxxxxx>
> ---
> v2->v3:
> * No change.
>
> v1->v2:
> * Split from patch 2/2 in v1. (Marek, Alexander)
>
> drivers/gpu/drm/mxsfb/lcdif_kms.c | 33 +++++++++++--------------------
> 1 file changed, 12 insertions(+), 21 deletions(-)
>
> diff --git a/drivers/gpu/drm/mxsfb/lcdif_kms.c
> b/drivers/gpu/drm/mxsfb/lcdif_kms.c index 262bc43b1079..e54200a9fcb9 100644
> --- a/drivers/gpu/drm/mxsfb/lcdif_kms.c
> +++ b/drivers/gpu/drm/mxsfb/lcdif_kms.c
> @@ -394,7 +394,7 @@ static void lcdif_crtc_mode_set_nofb(struct
> lcdif_drm_private *lcdif, struct drm_display_mode *m =
> &lcdif->crtc.state->adjusted_mode;
> u32 bus_flags = 0;
>
> - if (lcdif->bridge && lcdif->bridge->timings)
> + if (lcdif->bridge->timings)
> bus_flags = lcdif->bridge->timings->input_bus_flags;
> else if (bridge_state)
> bus_flags = bridge_state->input_bus_cfg.flags;
> @@ -463,30 +463,21 @@ static void lcdif_crtc_atomic_enable(struct drm_crtc
> *crtc, struct drm_display_mode *m = &lcdif->crtc.state->adjusted_mode;
> struct drm_bridge_state *bridge_state = NULL;
> struct drm_device *drm = lcdif->drm;
> - u32 bus_format = 0;
> + u32 bus_format;
> dma_addr_t paddr;
>
> - /* If there is a bridge attached to the LCDIF, use its bus format */
> - if (lcdif->bridge) {
> - bridge_state =
> - drm_atomic_get_new_bridge_state(state,
> - lcdif-
>bridge);
> - if (!bridge_state)
> - bus_format = MEDIA_BUS_FMT_FIXED;
> - else
> - bus_format = bridge_state->input_bus_cfg.format;
> -
> - if (bus_format == MEDIA_BUS_FMT_FIXED) {
> - dev_warn_once(drm->dev,
> - "Bridge does not provide bus
format, assuming
> MEDIA_BUS_FMT_RGB888_1X24.\n" -
"Please fix bridge driver by
> handling atomic_get_input_bus_fmts.\n"); -
bus_format =
> MEDIA_BUS_FMT_RGB888_1X24;
> - }
> - }
> + bridge_state = drm_atomic_get_new_bridge_state(state, lcdif-
>bridge);
> + if (!bridge_state)
> + bus_format = MEDIA_BUS_FMT_FIXED;
> + else
> + bus_format = bridge_state->input_bus_cfg.format;
>
> - /* If all else fails, default to RGB888_1X24 */
> - if (!bus_format)
> + if (bus_format == MEDIA_BUS_FMT_FIXED) {
> + dev_warn_once(drm->dev,
> + "Bridge does not provide bus format,
assuming
> MEDIA_BUS_FMT_RGB888_1X24.\n" + "Please fix
bridge driver by
> handling atomic_get_input_bus_fmts.\n"); bus_format =
> MEDIA_BUS_FMT_RGB888_1X24;
> + }
>
> clk_set_rate(lcdif->clk, m->crtc_clock * 1000);


LGTM.
Reviewed-by: Alexander Stein <alexander.stein@xxxxxxxxxxxxxxx>

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