drm/omap: dsi: skip dsi_vc_enable_hs when already in correct mode

Simplify and optimize dsi_vc_enable_hs() so that it can be called
without checking the current HS/LP mode. Make dsi_vc_enable_hs() return
if the VC is already in the correct mode.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201215104657.802264-69-tomi.valkeinen@ti.com

diff --git a/drivers/gpu/drm/omapdrm/dss/dsi.c b/drivers/gpu/drm/omapdrm/dss/dsi.c
index 9499e424ec90f2b50d746b82a27804c937beb3e3..6d97ca018a62165671c30cece4ca04a2531de67d 100644 (file)
--- a/drivers/gpu/drm/omapdrm/dss/dsi.c
+++ b/drivers/gpu/drm/omapdrm/dss/dsi.c
@@ -341,7 +341,6 @@ struct dsi_data {
        int irq;
 
        bool is_enabled;
-       bool in_lp_mode;
 
        struct clk *dss_clk;
        struct regmap *syscon;
@@ -2443,6 +2442,9 @@ static void dsi_vc_enable_hs(struct omap_dss_device *dssdev, int vc,
 
        DSSDBG("dsi_vc_enable_hs(%d, %d)\n", vc, enable);
 
+       if (REG_GET(dsi, DSI_VC_CTRL(vc), 9, 9) == enable)
+               return;
+
        WARN_ON(!dsi_bus_is_locked(dsi));
 
        dsi_vc_enable(dsi, vc, 0);
@@ -2458,8 +2460,6 @@ static void dsi_vc_enable_hs(struct omap_dss_device *dssdev, int vc,
        /* start the DDR clock by sending a NULL packet */
        if (dsi->vm_timings.ddr_clk_always_on && enable)
                dsi_vc_send_null(dsi, vc, dsi->dsidev->channel);
-
-       dsi->in_lp_mode = !enable;
 }
 
 static void dsi_vc_flush_long_data(struct dsi_data *dsi, int vc)
@@ -4888,9 +4888,7 @@ static ssize_t _omap_dsi_host_transfer(struct dsi_data *dsi, int vc,
        struct omap_dss_device *dssdev = &dsi->output;
        int r;
 
-       if (!!(msg->flags & MIPI_DSI_MSG_USE_LPM) != dsi->in_lp_mode)
-               dsi_vc_enable_hs(dssdev, vc,
-                                !(msg->flags & MIPI_DSI_MSG_USE_LPM));
+       dsi_vc_enable_hs(dssdev, vc, !(msg->flags & MIPI_DSI_MSG_USE_LPM));
 
        switch (msg->type) {
        case MIPI_DSI_GENERIC_SHORT_WRITE_0_PARAM: