[v2,2/6] drm: lcdif: Drop unnecessary NULL pointer check on lcdif->bridge
Commit Message
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@nxp.com>
---
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(-)
Comments
On 1/25/23 07:40, Liu Ying wrote:
> 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.
Is it possible that a panel (instead of a bridge) be attached to LCDIFv3
e.g. in case of iMXRT ?
> Signed-off-by: Liu Ying <victor.liu@nxp.com>
> ---
> v1->v2:
> * Split from patch 2/2 in v1. (Marek, Alexander)
Much appreciated, thanks.
[...]
On Wed, 2023-01-25 at 14:56 +0100, Marek Vasut wrote:
> On 1/25/23 07:40, Liu Ying wrote:
> > 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.
>
> Is it possible that a panel (instead of a bridge) be attached to
> LCDIFv3
> e.g. in case of iMXRT ?
According to IMXRT1160 and IMXRT1170 reference manuals, it looks like
LCDIFv2(similar to LCDIFv3, but not the same) may connect to a parallel
display panel through a mux(either eLCDIF or LCDIFv2). That mux could
be a bridge. But, it doesn't matter, because devm_drm_of_get_bridge()
may create a panel bridge if a panel is connected directly(See
kerneldoc of devm_drm_of_get_bridge()).
Regards,
Liu Ying
>
> > Signed-off-by: Liu Ying <victor.liu@nxp.com>
> > ---
> > v1->v2:
> > * Split from patch 2/2 in v1. (Marek, Alexander)
>
> Much appreciated, thanks.
>
> [...]
@@ -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);