On Mon, 01 Nov 2021, He Ying <heying24@xxxxxxxxxx> wrote:
> From the comments of drm_for_each_connector_iter(), we know
> that "connector is only valid within the list body, if you
> want to use connector after calling drm_connector_list_iter_end()
> then you need to grab your own reference first using
> drm_connector_get()". So fix the wrong use of connector
> according to the comments and then call drm_connector_put()
> after using connector finishes.
>
> Signed-off-by: He Ying <heying24@xxxxxxxxxx>
Please use "drm/sun4i:" subject prefix for sun4i patches.
BR,
Jani.
> ---
> drivers/gpu/drm/sun4i/sun4i_tcon.c | 18 +++++++++++++-----
> 1 file changed, 13 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c b/drivers/gpu/drm/sun4i/sun4i_tcon.c
> index 9f06dec0fc61..24fa6784ee5f 100644
> --- a/drivers/gpu/drm/sun4i/sun4i_tcon.c
> +++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c
> @@ -47,12 +47,12 @@ static struct drm_connector *sun4i_tcon_get_connector(const struct drm_encoder *
> drm_connector_list_iter_begin(encoder->dev, &iter);
> drm_for_each_connector_iter(connector, &iter)
> if (connector->encoder == encoder) {
> - drm_connector_list_iter_end(&iter);
> - return connector;
> + drm_connector_get(connector);
> + break;
> }
> drm_connector_list_iter_end(&iter);
>
> - return NULL;
> + return connector;
> }
>
> static int sun4i_tcon_get_pixel_depth(const struct drm_encoder *encoder)
> @@ -65,6 +65,7 @@ static int sun4i_tcon_get_pixel_depth(const struct drm_encoder *encoder)
> return -EINVAL;
>
> info = &connector->display_info;
> + drm_connector_put(connector);
> if (info->num_bus_formats != 1)
> return -EINVAL;
>
> @@ -361,6 +362,7 @@ static void sun4i_tcon0_mode_set_cpu(struct sun4i_tcon *tcon,
> /* TODO support normal CPU interface modes */
> struct sun6i_dsi *dsi = encoder_to_sun6i_dsi(encoder);
> struct mipi_dsi_device *device = dsi->device;
> + struct drm_connector *connector;
> u8 bpp = mipi_dsi_pixel_format_to_bpp(device->format);
> u8 lanes = device->lanes;
> u32 block_space, start_delay;
> @@ -372,7 +374,9 @@ static void sun4i_tcon0_mode_set_cpu(struct sun4i_tcon *tcon,
> sun4i_tcon0_mode_set_common(tcon, mode);
>
> /* Set dithering if needed */
> - sun4i_tcon0_mode_set_dithering(tcon, sun4i_tcon_get_connector(encoder));
> + connector = sun4i_tcon_get_connector(encoder);
> + sun4i_tcon0_mode_set_dithering(tcon, connector);
> + drm_connector_put(connector);
>
> regmap_update_bits(tcon->regs, SUN4I_TCON0_CTL_REG,
> SUN4I_TCON0_CTL_IF_MASK,
> @@ -430,6 +434,7 @@ static void sun4i_tcon0_mode_set_lvds(struct sun4i_tcon *tcon,
> const struct drm_display_mode *mode)
> {
> unsigned int bp;
> + struct drm_connector *connector;
> u8 clk_delay;
> u32 reg, val = 0;
>
> @@ -440,7 +445,9 @@ static void sun4i_tcon0_mode_set_lvds(struct sun4i_tcon *tcon,
> sun4i_tcon0_mode_set_common(tcon, mode);
>
> /* Set dithering if needed */
> - sun4i_tcon0_mode_set_dithering(tcon, sun4i_tcon_get_connector(encoder));
> + connector = sun4i_tcon_get_connector(encoder);
> + sun4i_tcon0_mode_set_dithering(tcon, connector);
> + drm_connector_put(connector);
>
> /* Adjust clock delay */
> clk_delay = sun4i_tcon_get_clk_delay(mode, 0);
> @@ -518,6 +525,7 @@ static void sun4i_tcon0_mode_set_rgb(struct sun4i_tcon *tcon,
>
> /* Set dithering if needed */
> sun4i_tcon0_mode_set_dithering(tcon, connector);
> + drm_connector_put(connector);
>
> /* Adjust clock delay */
> clk_delay = sun4i_tcon_get_clk_delay(mode, 0);
--
Jani Nikula, Intel Open Source Graphics Center
