[PATCH v2] drm: rcar-du: lvds: Get mode from state
Fabrizio Castro
fabrizio.castro at bp.renesas.com
Mon Dec 16 17:39:55 UTC 2019
Hi Laurent,
Thank you for your patch!
> From: linux-renesas-soc-owner at vger.kernel.org <linux-renesas-soc-owner at vger.kernel.org> On Behalf Of Laurent Pinchart
> Sent: 13 December 2019 18:28
> Subject: [PATCH v2] drm: rcar-du: lvds: Get mode from state
>
> The R-Car LVDS encoder driver implements the bridge .mode_set()
> operation for the sole purpose of storing the mode in the LVDS private
> data, to be used later when enabling the encoder.
>
> Switch to the bridge .atomic_enable() and .atomic_disable() operations
> in order to access the global atomic state, and get the mode from the
> state instead. Remove both the unneeded .mode_set() operation and the
> display_mode and mode fields storing state data from the rcar_lvds
> private structure.
>
> As a side effect we get the CRTC from the state, replace the CRTC
> pointer retrieved through the bridge's encoder that shouldn't be used by
> atomic drivers.
>
> Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas at ideasonboard.com>
> ---
> Changes since v1:
>
> - Call .atomic_enable() on the companion
> - Set companion->encoder in .attach()
>
> The patch has been tested on the Draak board with the HDMI output in
> LVDS dual-link mode, and on the Salvator-XS board with the HDMI, VGA and
> LVDS outputs in single-link mode.
>
> ---
> drivers/gpu/drm/rcar-du/rcar_lvds.c | 158 +++++++++++++++-------------
> 1 file changed, 85 insertions(+), 73 deletions(-)
>
> diff --git a/drivers/gpu/drm/rcar-du/rcar_lvds.c b/drivers/gpu/drm/rcar-du/rcar_lvds.c
> index 8c6c172bbf2e..c550bfd59e71 100644
> --- a/drivers/gpu/drm/rcar-du/rcar_lvds.c
> +++ b/drivers/gpu/drm/rcar-du/rcar_lvds.c
> @@ -65,9 +65,6 @@ struct rcar_lvds {
> struct clk *dotclkin[2]; /* External DU clocks */
> } clocks;
>
> - struct drm_display_mode display_mode;
> - enum rcar_lvds_mode mode;
> -
> struct drm_bridge *companion;
> bool dual_link;
> };
> @@ -402,10 +399,51 @@ EXPORT_SYMBOL_GPL(rcar_lvds_clk_disable);
> * Bridge
> */
>
> -static void rcar_lvds_enable(struct drm_bridge *bridge)
> +static enum rcar_lvds_mode rcar_lvds_get_lvds_mode(struct rcar_lvds *lvds,
> + const struct drm_connector *connector)
> +{
> + const struct drm_display_info *info;
> + enum rcar_lvds_mode mode;
> +
> + /*
> + * There is no API yet to retrieve LVDS mode from a bridge, only panels
> + * are supported.
> + */
> + if (!lvds->panel)
> + return RCAR_LVDS_MODE_JEIDA;
> +
> + info = &connector->display_info;
> + if (!info->num_bus_formats || !info->bus_formats) {
> + dev_err(lvds->dev, "no LVDS bus format reported\n");
dev_warn perhaps?
Also, how about:
s/no LVDS bus format reported/no LVDS bus format reported, using JEIDA/
or something along those lines?
> + return RCAR_LVDS_MODE_JEIDA;
> + }
> +
> + switch (info->bus_formats[0]) {
> + case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG:
Shall we take the below into account here?
https://lwn.net/Articles/794944/
> + case MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA:
> + mode = RCAR_LVDS_MODE_JEIDA;
> + break;
> + case MEDIA_BUS_FMT_RGB888_1X7X4_SPWG:
> + mode = RCAR_LVDS_MODE_VESA;
> + break;
> + default:
> + dev_err(lvds->dev, "unsupported LVDS bus format 0x%04x\n",
> + info->bus_formats[0]);
dev_warn perhaps?
Also, how about:
s/unsupported LVDS bus format 0x%04x/unsupported LVDS bus format 0x%04x, using JEIDA/
or something along those lines?
> + return RCAR_LVDS_MODE_JEIDA;
> + }
> +
> + if (info->bus_flags & DRM_BUS_FLAG_DATA_LSB_TO_MSB)
> + mode |= RCAR_LVDS_MODE_MIRROR;
> +
> + return mode;
> +}
> +
> +static void rcar_lvds_atomic_enable(struct drm_bridge *bridge,
> + struct drm_atomic_state *state)
> {
> struct rcar_lvds *lvds = bridge_to_rcar_lvds(bridge);
> - const struct drm_display_mode *mode = &lvds->display_mode;
> + struct drm_connector *connector;
> + struct drm_crtc *crtc;
> u32 lvdhcr;
> u32 lvdcr0;
> int ret;
> @@ -414,9 +452,14 @@ static void rcar_lvds_enable(struct drm_bridge *bridge)
> if (ret < 0)
> return;
>
> + /* Retrieve the connector and CRTC through the atomic state. */
> + connector = drm_atomic_get_new_connector_for_encoder(state,
> + bridge->encoder);
> + crtc = drm_atomic_get_new_connector_state(state, connector)->crtc;
> +
> /* Enable the companion LVDS encoder in dual-link mode. */
> if (lvds->dual_link && lvds->companion)
> - lvds->companion->funcs->enable(lvds->companion);
> + lvds->companion->funcs->atomic_enable(lvds->companion, state);
>
> /*
> * Hardcode the channels and control signals routing for now.
> @@ -452,18 +495,20 @@ static void rcar_lvds_enable(struct drm_bridge *bridge)
> * PLL clock configuration on all instances but the companion in
> * dual-link mode.
> */
> - if (!lvds->dual_link || lvds->companion)
> + if (!lvds->dual_link || lvds->companion) {
> + const struct drm_crtc_state *crtc_state =
> + drm_atomic_get_new_crtc_state(state, crtc);
> + const struct drm_display_mode *mode =
> + &crtc_state->adjusted_mode;
> +
> lvds->info->pll_setup(lvds, mode->clock * 1000);
> + }
>
> /* Set the LVDS mode and select the input. */
> - lvdcr0 = lvds->mode << LVDCR0_LVMD_SHIFT;
> + lvdcr0 = rcar_lvds_get_lvds_mode(lvds, connector) << LVDCR0_LVMD_SHIFT;
>
> if (lvds->bridge.encoder) {
> - /*
> - * FIXME: We should really retrieve the CRTC through the state,
> - * but how do we get a state pointer?
> - */
> - if (drm_crtc_index(lvds->bridge.encoder->crtc) == 2)
> + if (drm_crtc_index(crtc) == 2)
> lvdcr0 |= LVDCR0_DUSEL;
> }
>
> @@ -520,7 +565,8 @@ static void rcar_lvds_enable(struct drm_bridge *bridge)
> }
> }
>
> -static void rcar_lvds_disable(struct drm_bridge *bridge)
> +static void rcar_lvds_atomic_disable(struct drm_bridge *bridge,
> + struct drm_atomic_state *state)
> {
> struct rcar_lvds *lvds = bridge_to_rcar_lvds(bridge);
>
> @@ -558,54 +604,6 @@ static bool rcar_lvds_mode_fixup(struct drm_bridge *bridge,
> return true;
> }
>
> -static void rcar_lvds_get_lvds_mode(struct rcar_lvds *lvds)
> -{
> - struct drm_display_info *info = &lvds->connector.display_info;
> - enum rcar_lvds_mode mode;
> -
> - /*
> - * There is no API yet to retrieve LVDS mode from a bridge, only panels
> - * are supported.
> - */
> - if (!lvds->panel)
> - return;
> -
> - if (!info->num_bus_formats || !info->bus_formats) {
> - dev_err(lvds->dev, "no LVDS bus format reported\n");
> - return;
> - }
> -
> - switch (info->bus_formats[0]) {
> - case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG:
> - case MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA:
> - mode = RCAR_LVDS_MODE_JEIDA;
> - break;
> - case MEDIA_BUS_FMT_RGB888_1X7X4_SPWG:
> - mode = RCAR_LVDS_MODE_VESA;
> - break;
> - default:
> - dev_err(lvds->dev, "unsupported LVDS bus format 0x%04x\n",
> - info->bus_formats[0]);
> - return;
> - }
> -
> - if (info->bus_flags & DRM_BUS_FLAG_DATA_LSB_TO_MSB)
> - mode |= RCAR_LVDS_MODE_MIRROR;
> -
> - lvds->mode = mode;
> -}
> -
> -static void rcar_lvds_mode_set(struct drm_bridge *bridge,
> - const struct drm_display_mode *mode,
> - const struct drm_display_mode *adjusted_mode)
> -{
> - struct rcar_lvds *lvds = bridge_to_rcar_lvds(bridge);
> -
> - lvds->display_mode = *adjusted_mode;
> -
> - rcar_lvds_get_lvds_mode(lvds);
> -}
> -
> static int rcar_lvds_attach(struct drm_bridge *bridge)
> {
> struct rcar_lvds *lvds = bridge_to_rcar_lvds(bridge);
> @@ -614,32 +612,47 @@ static int rcar_lvds_attach(struct drm_bridge *bridge)
> int ret;
>
> /* If we have a next bridge just attach it. */
> - if (lvds->next_bridge)
> - return drm_bridge_attach(bridge->encoder, lvds->next_bridge,
> - bridge);
> + if (lvds->next_bridge) {
> + ret = drm_bridge_attach(bridge->encoder, lvds->next_bridge,
> + bridge);
> + goto done;
> + }
>
> /* Otherwise if we have a panel, create a connector. */
It doesn't look like this comment is in the right place. We should probably move this
comment below and add a new comment here. What do you think?
> - if (!lvds->panel)
> - return 0;
> + if (!lvds->panel) {
> + ret = 0;
> + goto done;
> + }
>
> ret = drm_connector_init(bridge->dev, connector, &rcar_lvds_conn_funcs,
> DRM_MODE_CONNECTOR_LVDS);
> if (ret < 0)
> - return ret;
> + goto done;
>
> drm_connector_helper_add(connector, &rcar_lvds_conn_helper_funcs);
>
> ret = drm_connector_attach_encoder(connector, encoder);
> if (ret < 0)
> - return ret;
> + goto done;
> +
> + ret = drm_panel_attach(lvds->panel, connector);
>
> - return drm_panel_attach(lvds->panel, connector);
> +done:
> + if (!ret) {
> + if (lvds->companion)
> + lvds->companion->encoder = encoder;
> + }
How about replacing the above with:
if (!ret && lvds->companion)
lvds->companion->encoder = encoder;
Also, I am not a DRM expert, so this comment might have no real value,
but I do wonder if tampering with the drm_bridge structure for the companion
encoder is safe to do here?
> +
> + return 0;
> }
>
> static void rcar_lvds_detach(struct drm_bridge *bridge)
> {
> struct rcar_lvds *lvds = bridge_to_rcar_lvds(bridge);
>
> + if (lvds->companion)
> + lvds->companion->encoder = NULL;
> +
> if (lvds->panel)
> drm_panel_detach(lvds->panel);
> }
> @@ -647,10 +660,9 @@ static void rcar_lvds_detach(struct drm_bridge *bridge)
> static const struct drm_bridge_funcs rcar_lvds_bridge_ops = {
> .attach = rcar_lvds_attach,
> .detach = rcar_lvds_detach,
> - .enable = rcar_lvds_enable,
> - .disable = rcar_lvds_disable,
> + .atomic_enable = rcar_lvds_atomic_enable,
> + .atomic_disable = rcar_lvds_atomic_disable,
> .mode_fixup = rcar_lvds_mode_fixup,
> - .mode_set = rcar_lvds_mode_set,
> };
>
> bool rcar_lvds_dual_link(struct drm_bridge *bridge)
I did test this patch on the RZ/G2E with dual-link support and it seems to be working
just fine.
Cheers,
Fab
> --
> Regards,
>
> Laurent Pinchart
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