[PATCH v2] drm/bridge: nwl-dsi: Get MIPI DSI controller and PHY ready in ->mode_set()
Neil Armstrong
narmstrong at baylibre.com
Thu Apr 22 08:48:55 UTC 2021
Hi,
On 22/04/2021 07:14, Liu Ying wrote:
> Some MIPI DSI panel drivers like 'raydium,rm68200' send
> MIPI_DCS_SET_DISPLAY_ON commands in panel_funcs->prepare(), which
> requires the MIPI DSI controller and PHY to be ready beforehand.
> Without this patch, the nwl-dsi driver gets the MIPI DSI controller
> and PHY ready in bridge_funcs->pre_enable(), which happens after
> the panel_funcs->prepare(). So, this patch shifts the bridge operation
> ealier from bridge_funcs->pre_enable() to bridge_funcs->mode_set().
This makes sense, this is how we do on the synopsys dw mipi dsi driver.
> This way, more MIPI DSI panels can connect to this nwl-dsi bridge.
> Care is taken to make sure bridge_funcs->mode_set()/atomic_disable()
> are called in pairs, which includes removing a check on unchanged HS
> clock rate and forcing a full modeset when only connector's DPMS is
> brought out of "Off" status.
I would split the changes in multiple patches to clarify the changes.
Neil
>
> Cc: Andrzej Hajda <a.hajda at samsung.com>
> Cc: Neil Armstrong <narmstrong at baylibre.com>
> Cc: Robert Foss <robert.foss at linaro.org>
> Cc: Laurent Pinchart <Laurent.pinchart at ideasonboard.com>
> Cc: Jonas Karlman <jonas at kwiboo.se>
> Cc: Jernej Skrabec <jernej.skrabec at siol.net>
> Cc: David Airlie <airlied at linux.ie>
> Cc: Daniel Vetter <daniel at ffwll.ch>
> Cc: Guido Günther <agx at sigxcpu.org>
> Cc: Robert Chiras <robert.chiras at nxp.com>
> Cc: NXP Linux Team <linux-imx at nxp.com>
> Signed-off-by: Liu Ying <victor.liu at nxp.com>
> ---
> v1->v2:
> * Fix commit message typo - s/unchange/unchanged/
>
> drivers/gpu/drm/bridge/nwl-dsi.c | 86 +++++++++++++++++++++-------------------
> 1 file changed, 46 insertions(+), 40 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/nwl-dsi.c b/drivers/gpu/drm/bridge/nwl-dsi.c
> index be6bfc5..229f0b1 100644
> --- a/drivers/gpu/drm/bridge/nwl-dsi.c
> +++ b/drivers/gpu/drm/bridge/nwl-dsi.c
> @@ -21,6 +21,7 @@
> #include <linux/sys_soc.h>
> #include <linux/time64.h>
>
> +#include <drm/drm_atomic_state_helper.h>
> #include <drm/drm_bridge.h>
> #include <drm/drm_mipi_dsi.h>
> #include <drm/drm_of.h>
> @@ -661,7 +662,7 @@ static irqreturn_t nwl_dsi_irq_handler(int irq, void *data)
> return IRQ_HANDLED;
> }
>
> -static int nwl_dsi_enable(struct nwl_dsi *dsi)
> +static int nwl_dsi_mode_set(struct nwl_dsi *dsi)
> {
> struct device *dev = dsi->dev;
> union phy_configure_opts *phy_cfg = &dsi->phy_cfg;
> @@ -748,7 +749,9 @@ static int nwl_dsi_disable(struct nwl_dsi *dsi)
> return 0;
> }
>
> -static void nwl_dsi_bridge_disable(struct drm_bridge *bridge)
> +static void
> +nwl_dsi_bridge_atomic_disable(struct drm_bridge *bridge,
> + struct drm_bridge_state *old_bridge_state)
> {
> struct nwl_dsi *dsi = bridge_to_dsi(bridge);
> int ret;
> @@ -809,17 +812,6 @@ static int nwl_dsi_get_dphy_params(struct nwl_dsi *dsi,
> return 0;
> }
>
> -static bool nwl_dsi_bridge_mode_fixup(struct drm_bridge *bridge,
> - const struct drm_display_mode *mode,
> - struct drm_display_mode *adjusted_mode)
> -{
> - /* At least LCDIF + NWL needs active high sync */
> - adjusted_mode->flags |= (DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_PVSYNC);
> - adjusted_mode->flags &= ~(DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC);
> -
> - return true;
> -}
> -
> static enum drm_mode_status
> nwl_dsi_bridge_mode_valid(struct drm_bridge *bridge,
> const struct drm_display_info *info,
> @@ -837,6 +829,29 @@ nwl_dsi_bridge_mode_valid(struct drm_bridge *bridge,
> return MODE_OK;
> }
>
> +static int nwl_dsi_bridge_atomic_check(struct drm_bridge *bridge,
> + struct drm_bridge_state *bridge_state,
> + struct drm_crtc_state *crtc_state,
> + struct drm_connector_state *conn_state)
> +{
> + struct drm_display_mode *adjusted_mode = &crtc_state->adjusted_mode;
> +
> + /* At least LCDIF + NWL needs active high sync */
> + adjusted_mode->flags |= (DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_PVSYNC);
> + adjusted_mode->flags &= ~(DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC);
> +
> + /*
> + * Do a full modeset if crtc_state->active is changed to be true.
> + * This ensures our ->mode_set() is called to get the DSI controller
> + * and the PHY ready to send DCS commands, when only the connector's
> + * DPMS is brought out of "Off" status.
> + */
> + if (crtc_state->active_changed && crtc_state->active)
> + crtc_state->mode_changed = true;
> +
> + return 0;
> +}
> +
> static void
> nwl_dsi_bridge_mode_set(struct drm_bridge *bridge,
> const struct drm_display_mode *mode,
> @@ -852,13 +867,6 @@ nwl_dsi_bridge_mode_set(struct drm_bridge *bridge,
> if (ret < 0)
> return;
>
> - /*
> - * If hs clock is unchanged, we're all good - all parameters are
> - * derived from it atm.
> - */
> - if (new_cfg.mipi_dphy.hs_clk_rate == dsi->phy_cfg.mipi_dphy.hs_clk_rate)
> - return;
> -
> phy_ref_rate = clk_get_rate(dsi->phy_ref_clk);
> DRM_DEV_DEBUG_DRIVER(dev, "PHY at ref rate: %lu\n", phy_ref_rate);
> /* Save the new desired phy config */
> @@ -866,14 +874,8 @@ nwl_dsi_bridge_mode_set(struct drm_bridge *bridge,
>
> memcpy(&dsi->mode, adjusted_mode, sizeof(dsi->mode));
> drm_mode_debug_printmodeline(adjusted_mode);
> -}
>
> -static void nwl_dsi_bridge_pre_enable(struct drm_bridge *bridge)
> -{
> - struct nwl_dsi *dsi = bridge_to_dsi(bridge);
> - int ret;
> -
> - pm_runtime_get_sync(dsi->dev);
> + pm_runtime_get_sync(dev);
>
> if (clk_prepare_enable(dsi->lcdif_clk) < 0)
> return;
> @@ -883,27 +885,29 @@ static void nwl_dsi_bridge_pre_enable(struct drm_bridge *bridge)
> /* Step 1 from DSI reset-out instructions */
> ret = reset_control_deassert(dsi->rst_pclk);
> if (ret < 0) {
> - DRM_DEV_ERROR(dsi->dev, "Failed to deassert PCLK: %d\n", ret);
> + DRM_DEV_ERROR(dev, "Failed to deassert PCLK: %d\n", ret);
> return;
> }
>
> /* Step 2 from DSI reset-out instructions */
> - nwl_dsi_enable(dsi);
> + nwl_dsi_mode_set(dsi);
>
> /* Step 3 from DSI reset-out instructions */
> ret = reset_control_deassert(dsi->rst_esc);
> if (ret < 0) {
> - DRM_DEV_ERROR(dsi->dev, "Failed to deassert ESC: %d\n", ret);
> + DRM_DEV_ERROR(dev, "Failed to deassert ESC: %d\n", ret);
> return;
> }
> ret = reset_control_deassert(dsi->rst_byte);
> if (ret < 0) {
> - DRM_DEV_ERROR(dsi->dev, "Failed to deassert BYTE: %d\n", ret);
> + DRM_DEV_ERROR(dev, "Failed to deassert BYTE: %d\n", ret);
> return;
> }
> }
>
> -static void nwl_dsi_bridge_enable(struct drm_bridge *bridge)
> +static void
> +nwl_dsi_bridge_atomic_enable(struct drm_bridge *bridge,
> + struct drm_bridge_state *old_bridge_state)
> {
> struct nwl_dsi *dsi = bridge_to_dsi(bridge);
> int ret;
> @@ -948,14 +952,16 @@ static void nwl_dsi_bridge_detach(struct drm_bridge *bridge)
> }
>
> static const struct drm_bridge_funcs nwl_dsi_bridge_funcs = {
> - .pre_enable = nwl_dsi_bridge_pre_enable,
> - .enable = nwl_dsi_bridge_enable,
> - .disable = nwl_dsi_bridge_disable,
> - .mode_fixup = nwl_dsi_bridge_mode_fixup,
> - .mode_set = nwl_dsi_bridge_mode_set,
> - .mode_valid = nwl_dsi_bridge_mode_valid,
> - .attach = nwl_dsi_bridge_attach,
> - .detach = nwl_dsi_bridge_detach,
> + .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
> + .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
> + .atomic_reset = drm_atomic_helper_bridge_reset,
> + .atomic_check = nwl_dsi_bridge_atomic_check,
> + .atomic_enable = nwl_dsi_bridge_atomic_enable,
> + .atomic_disable = nwl_dsi_bridge_atomic_disable,
> + .mode_set = nwl_dsi_bridge_mode_set,
> + .mode_valid = nwl_dsi_bridge_mode_valid,
> + .attach = nwl_dsi_bridge_attach,
> + .detach = nwl_dsi_bridge_detach,
> };
>
> static int nwl_dsi_parse_dt(struct nwl_dsi *dsi)
>
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