Re: [PATCH 4/4] drm: rcar-du: mipi-dsi: Support bridge probe ordering

Hi Jagan,

Quoting Jagan Teki (2021-11-30 07:38:57)

Hi Kieran,

On Fri, Nov 26, 2021 at 3:45 PM Kieran Bingham kieran.bingham+renesas@ideasonboard.com wrote:

...

The bridge probe ordering for DSI devices has been clarified and further documented in

To support connecting with the SN65DSI86 device after commit c3b75d4734cb ("drm/bridge: sn65dsi86: Register and attach our DSI device at probe"), update to the new probe ordering to remove a perpetual -EPROBE_DEFER loop between the two devices.

Signed-off-by: Kieran Bingham kieran.bingham+renesas@ideasonboard.com

drivers/gpu/drm/rcar-du/rcar_mipi_dsi.c | 48 +++++++++++++------------ 1 file changed, 26 insertions(+), 22 deletions(-)

diff --git a/drivers/gpu/drm/rcar-du/rcar_mipi_dsi.c b/drivers/gpu/drm/rcar-du/rcar_mipi_dsi.c index 833f4480bdf3..f783bacee8da 100644 --- a/drivers/gpu/drm/rcar-du/rcar_mipi_dsi.c +++ b/drivers/gpu/drm/rcar-du/rcar_mipi_dsi.c @@ -639,6 +639,8 @@ static int rcar_mipi_dsi_host_attach(struct mipi_dsi_host *host, struct mipi_dsi_device *device) { struct rcar_mipi_dsi *dsi = host_to_rcar_mipi_dsi(host);

•   struct drm_panel *panel;
  

•   int ret;
  
    if (device->lanes > dsi->num_data_lanes)
            return -EINVAL;
  

@@ -646,12 +648,36 @@ static int rcar_mipi_dsi_host_attach(struct mipi_dsi_host *host, dsi->lanes = device->lanes; dsi->format = device->format;

•   ret = drm_of_find_panel_or_bridge(dsi->dev->of_node, 1, 0, &panel,
  

•                                     &dsi->next_bridge);
  

•   if (ret) {
  

•           dev_err_probe(dsi->dev, ret, "could not find next bridge\n");
  

•           return ret;
  

•   }
  

•   if (!dsi->next_bridge) {
  

•           dsi->next_bridge = devm_drm_panel_bridge_add(dsi->dev, panel);
  

•           if (IS_ERR(dsi->next_bridge)) {
  

•                   dev_err(dsi->dev, "failed to create panel bridge\n");
  

•                   return PTR_ERR(dsi->next_bridge);
  

•           }
  

•   }
  

Can we use the new function devm_drm_of_get_bridge instead of the entire code?

I've just tried this, and it works, so yes we can. I'll update the branch and re-send it for Laurent to collect and apply/squash whichever works best.

Thanks.

Kieran

Jagan.