Re: [PATCH v2 3/7] drm: rcar-du: lvsd: Add reset control

[Tomi Valkeinen]

On 20/01/2023 19:05, Laurent Pinchart wrote:

On Fri, Jan 20, 2023 at 06:18:07PM +0200, Laurent Pinchart wrote:

Hi Tomi,

Thank you for the patch.

Another small comment: in the commit message, s/lvsd/lvds/

Yep.

On Fri, Jan 20, 2023 at 10:50:05AM +0200, Tomi Valkeinen wrote:

Reset LVDS using the reset control as CPG reset/release is required in
the hardware manual sequence.

Based on a BSP patch from Koji Matsuoka <koji.matsuoka...@renesas.com>.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen+rene...@ideasonboard.com>
---
  drivers/gpu/drm/rcar-du/Kconfig     |  1 +
  drivers/gpu/drm/rcar-du/rcar_lvds.c | 19 ++++++++++++++++++-
  2 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/rcar-du/Kconfig b/drivers/gpu/drm/rcar-du/Kconfig
index a8f862c68b4f..151e400b996d 100644
--- a/drivers/gpu/drm/rcar-du/Kconfig
+++ b/drivers/gpu/drm/rcar-du/Kconfig
@@ -43,6 +43,7 @@ config DRM_RCAR_LVDS
        select DRM_PANEL
        select OF_FLATTREE
        select OF_OVERLAY
+       select RESET_CONTROLLER

config DRM_RCAR_USE_MIPI_DSI

        bool "R-Car DU MIPI DSI Encoder Support"
diff --git a/drivers/gpu/drm/rcar-du/rcar_lvds.c 
b/drivers/gpu/drm/rcar-du/rcar_lvds.c
index 8e1be51fbee6..668604616bfd 100644
--- a/drivers/gpu/drm/rcar-du/rcar_lvds.c
+++ b/drivers/gpu/drm/rcar-du/rcar_lvds.c
@@ -17,6 +17,7 @@
  #include <linux/of_graph.h>
  #include <linux/platform_device.h>
  #include <linux/pm_runtime.h>
+#include <linux/reset.h>
  #include <linux/slab.h>
  #include <linux/sys_soc.h>

@@ -61,6 +62,7 @@ struct rcar_lvds_device_info {

  struct rcar_lvds {
        struct device *dev;
        const struct rcar_lvds_device_info *info;
+       struct reset_control *rstc;

struct drm_bridge bridge; @@ -845,6 +847,10 @@ static int rcar_lvds_probe(struct platform_device *pdev)

        if (ret < 0)
                return ret;

+ lvds->rstc = devm_reset_control_get_exclusive(&pdev->dev, NULL);

+       if (IS_ERR(lvds->rstc))
+               return dev_err_probe(&pdev->dev, PTR_ERR(lvds->rstc),
+                                    "failed to get cpg reset\n");

Missing blank line.

Reviewed-by: Laurent Pinchart <laurent.pinch...@ideasonboard.com>

Thanks!

 Tomi