Re: [Freedreno] [PATCH] drm/msm/dp: Use the connector passed to dp_debug_get()

[abhinavk]

On 2021-10-12 16:38, Bjorn Andersson wrote:
On Tue 12 Oct 16:03 PDT 2021, abhin...@codeaurora.org wrote:
On 2021-10-09 20:04, Bjorn Andersson wrote:
> The debugfs code is provided an array of a single drm_connector. Then to
> access the connector, the list of all connectors of the DRM device is
> traversed and all non-DisplayPort connectors are skipped, to find the
> one and only DisplayPort connector.
>
> But as we move to support multiple DisplayPort controllers this will now
> find multiple connectors and has no way to distinguish them.
>
> Pass the single connector to dp_debug_get() and use this in the debugfs
> functions instead, both to simplify the code and the support the
> multiple instances.
>
Change itself is fine, hence
Reviewed-by: Abhinav Kumar <abhin...@codeaurora.org>


Thanks.

What has to be checked now is now to create multiple DP nodes for 
multi-DP
cases.
Today, the debug node will be created only once :

https://gitlab.freedesktop.org/drm/msm/-/blob/msm-next/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c#L206

This also needs to be expanded for multi-DP to make the solution 
complete.


In my multi-DP support patch I end up invoking msm_dp_debugfs_init() 
for
each of the DP/eDP instances and in its current form the first one gets
registered and any others will fail because of the resulting name
collision.

This patch came as a byproduct of the effort of addressing that 
problem.

Regards,
Bjorn

Ah, okay. Yes i see the part you are referring to in 
https://patchwork.freedesktop.org/patch/457667/:

@@ -203,8 +204,10 @@  static int dpu_kms_debugfs_init(struct msm_kms 
*kms, struct drm_minor *minor)
        dpu_debugfs_vbif_init(dpu_kms, entry);
        dpu_debugfs_core_irq_init(dpu_kms, entry);

-       if (priv->dp)
-               msm_dp_debugfs_init(priv->dp, minor);
+       for (i = 0; i < ARRAY_SIZE(priv->dp); i++) {
+               if (priv->dp[i])
+                       msm_dp_debugfs_init(priv->dp[i], minor);
+       }

That clarifies it. Thanks.


> Signed-off-by: Bjorn Andersson <bjorn.anders...@linaro.org>
> ---
>  drivers/gpu/drm/msm/dp/dp_debug.c   | 131 ++++++++++------------------
>  drivers/gpu/drm/msm/dp/dp_debug.h   |   2 +-
>  drivers/gpu/drm/msm/dp/dp_display.c |   2 +-
>  3 files changed, 46 insertions(+), 89 deletions(-)
>
> diff --git a/drivers/gpu/drm/msm/dp/dp_debug.c
> b/drivers/gpu/drm/msm/dp/dp_debug.c
> index af709d93bb9f..da4323556ef3 100644
> --- a/drivers/gpu/drm/msm/dp/dp_debug.c
> +++ b/drivers/gpu/drm/msm/dp/dp_debug.c
> @@ -24,7 +24,7 @@ struct dp_debug_private {
>    struct dp_usbpd *usbpd;
>    struct dp_link *link;
>    struct dp_panel *panel;
> -  struct drm_connector **connector;
> +  struct drm_connector *connector;
>    struct device *dev;
>    struct drm_device *drm_dev;
>
> @@ -97,59 +97,35 @@ DEFINE_SHOW_ATTRIBUTE(dp_debug);
>
>  static int dp_test_data_show(struct seq_file *m, void *data)
>  {
> -  struct drm_device *dev;
> -  struct dp_debug_private *debug;
> -  struct drm_connector *connector;
> -  struct drm_connector_list_iter conn_iter;
> +  const struct dp_debug_private *debug = m->private;
> +  const struct drm_connector *connector = debug->connector;
>    u32 bpc;
>
> -  debug = m->private;
> -  dev = debug->drm_dev;
> -  drm_connector_list_iter_begin(dev, &conn_iter);
> -  drm_for_each_connector_iter(connector, &conn_iter) {
> -
> -          if (connector->connector_type !=
> -                  DRM_MODE_CONNECTOR_DisplayPort)
> -                  continue;
> -
> -          if (connector->status == connector_status_connected) {
> -                  bpc = debug->link->test_video.test_bit_depth;
> -                  seq_printf(m, "hdisplay: %d\n",
> -                                  debug->link->test_video.test_h_width);
> -                  seq_printf(m, "vdisplay: %d\n",
> -                                  debug->link->test_video.test_v_height);
> -                  seq_printf(m, "bpc: %u\n",
> -                                  dp_link_bit_depth_to_bpc(bpc));
> -          } else
> -                  seq_puts(m, "0");
> +  if (connector->status == connector_status_connected) {
> +          bpc = debug->link->test_video.test_bit_depth;
> +          seq_printf(m, "hdisplay: %d\n",
> +                          debug->link->test_video.test_h_width);
> +          seq_printf(m, "vdisplay: %d\n",
> +                          debug->link->test_video.test_v_height);
> +          seq_printf(m, "bpc: %u\n",
> +                          dp_link_bit_depth_to_bpc(bpc));
> +  } else {
> +          seq_puts(m, "0");
>    }
>
> -  drm_connector_list_iter_end(&conn_iter);
> -
>    return 0;
>  }
>  DEFINE_SHOW_ATTRIBUTE(dp_test_data);
>
>  static int dp_test_type_show(struct seq_file *m, void *data)
>  {
> -  struct dp_debug_private *debug = m->private;
> -  struct drm_device *dev = debug->drm_dev;
> -  struct drm_connector *connector;
> -  struct drm_connector_list_iter conn_iter;
> -
> -  drm_connector_list_iter_begin(dev, &conn_iter);
> -  drm_for_each_connector_iter(connector, &conn_iter) {
> -
> -          if (connector->connector_type !=
> -                  DRM_MODE_CONNECTOR_DisplayPort)
> -                  continue;
> +  const struct dp_debug_private *debug = m->private;
> +  const struct drm_connector *connector = debug->connector;
>
> -          if (connector->status == connector_status_connected)
> -                  seq_printf(m, "%02x", DP_TEST_LINK_VIDEO_PATTERN);
> -          else
> -                  seq_puts(m, "0");
> -  }
> -  drm_connector_list_iter_end(&conn_iter);
> +  if (connector->status == connector_status_connected)
> +          seq_printf(m, "%02x", DP_TEST_LINK_VIDEO_PATTERN);
> +  else
> +          seq_puts(m, "0");
>
>    return 0;
>  }
> @@ -161,14 +137,12 @@ static ssize_t dp_test_active_write(struct file
> *file,
>  {
>    char *input_buffer;
>    int status = 0;
> -  struct dp_debug_private *debug;
> -  struct drm_device *dev;
> -  struct drm_connector *connector;
> -  struct drm_connector_list_iter conn_iter;
> +  const struct dp_debug_private *debug;
> +  const struct drm_connector *connector;
>    int val = 0;
>
>    debug = ((struct seq_file *)file->private_data)->private;
> -  dev = debug->drm_dev;
> +  connector = debug->connector;
>
>    if (len == 0)
>            return 0;
> @@ -179,30 +153,22 @@ static ssize_t dp_test_active_write(struct file
> *file,
>
>    DRM_DEBUG_DRIVER("Copied %d bytes from user\n", (unsigned int)len);
>
> -  drm_connector_list_iter_begin(dev, &conn_iter);
> -  drm_for_each_connector_iter(connector, &conn_iter) {
> -          if (connector->connector_type !=
> -                  DRM_MODE_CONNECTOR_DisplayPort)
> -                  continue;
> -
> -          if (connector->status == connector_status_connected) {
> -                  status = kstrtoint(input_buffer, 10, &val);
> -                  if (status < 0)
> -                          break;
> -                  DRM_DEBUG_DRIVER("Got %d for test active\n", val);
> -                  /* To prevent erroneous activation of the compliance
> -                   * testing code, only accept an actual value of 1 here
> -                   */
> -                  if (val == 1)
> -                          debug->panel->video_test = true;
> -                  else
> -                          debug->panel->video_test = false;
> +  if (connector->status == connector_status_connected) {
> +          status = kstrtoint(input_buffer, 10, &val);
> +          if (status < 0) {
> +                  kfree(input_buffer);
> +                  return status;
>            }
> +          DRM_DEBUG_DRIVER("Got %d for test active\n", val);
> +          /* To prevent erroneous activation of the compliance
> +           * testing code, only accept an actual value of 1 here
> +           */
> +          if (val == 1)
> +                  debug->panel->video_test = true;
> +          else
> +                  debug->panel->video_test = false;
>    }
> -  drm_connector_list_iter_end(&conn_iter);
>    kfree(input_buffer);
> -  if (status < 0)
> -          return status;
>
>    *offp += len;
>    return len;
> @@ -211,25 +177,16 @@ static ssize_t dp_test_active_write(struct file
> *file,
>  static int dp_test_active_show(struct seq_file *m, void *data)
>  {
>    struct dp_debug_private *debug = m->private;
> -  struct drm_device *dev = debug->drm_dev;
> -  struct drm_connector *connector;
> -  struct drm_connector_list_iter conn_iter;
> -
> -  drm_connector_list_iter_begin(dev, &conn_iter);
> -  drm_for_each_connector_iter(connector, &conn_iter) {
> -          if (connector->connector_type !=
> -                  DRM_MODE_CONNECTOR_DisplayPort)
> -                  continue;
> -
> -          if (connector->status == connector_status_connected) {
> -                  if (debug->panel->video_test)
> -                          seq_puts(m, "1");
> -                  else
> -                          seq_puts(m, "0");
> -          } else
> +  struct drm_connector *connector = debug->connector;
> +
> +  if (connector->status == connector_status_connected) {
> +          if (debug->panel->video_test)
> +                  seq_puts(m, "1");
> +          else
>                    seq_puts(m, "0");
> +  } else {
> +          seq_puts(m, "0");
>    }
> -  drm_connector_list_iter_end(&conn_iter);
>
>    return 0;
>  }
> @@ -278,7 +235,7 @@ static int dp_debug_init(struct dp_debug
> *dp_debug, struct drm_minor *minor)
>
>  struct dp_debug *dp_debug_get(struct device *dev, struct dp_panel
> *panel,
>            struct dp_usbpd *usbpd, struct dp_link *link,
> -          struct drm_connector **connector, struct drm_minor *minor)
> +          struct drm_connector *connector, struct drm_minor *minor)
>  {
>    int rc = 0;
>    struct dp_debug_private *debug;
> diff --git a/drivers/gpu/drm/msm/dp/dp_debug.h
> b/drivers/gpu/drm/msm/dp/dp_debug.h
> index 7eaedfbb149c..3f90acfffc5a 100644
> --- a/drivers/gpu/drm/msm/dp/dp_debug.h
> +++ b/drivers/gpu/drm/msm/dp/dp_debug.h
> @@ -43,7 +43,7 @@ struct dp_debug {
>   */
>  struct dp_debug *dp_debug_get(struct device *dev, struct dp_panel
> *panel,
>            struct dp_usbpd *usbpd, struct dp_link *link,
> -          struct drm_connector **connector,
> +          struct drm_connector *connector,
>            struct drm_minor *minor);
>
>  /**
> diff --git a/drivers/gpu/drm/msm/dp/dp_display.c
> b/drivers/gpu/drm/msm/dp/dp_display.c
> index 1708b7cdc1b3..41a6f58916e6 100644
> --- a/drivers/gpu/drm/msm/dp/dp_display.c
> +++ b/drivers/gpu/drm/msm/dp/dp_display.c
> @@ -1464,7 +1464,7 @@ void msm_dp_debugfs_init(struct msm_dp
> *dp_display, struct drm_minor *minor)
>    dev = &dp->pdev->dev;
>
>    dp->debug = dp_debug_get(dev, dp->panel, dp->usbpd,
> -                                  dp->link, &dp->dp_display.connector,
> +                                  dp->link, dp->dp_display.connector,
>                                    minor);
>    if (IS_ERR(dp->debug)) {
>            rc = PTR_ERR(dp->debug);