drm/bridge: samsung-dsim: add SFRCTRL register

On Exynos7870 devices, enabling the display requires disabling
standby by writing to the SFRCTRL register. Add the register and related
bit values. Since this behavior isn't available on other SoCs, implement
a flag in the driver data struct indicating the availability of this
feature.

Signed-off-by: Kaustabh Chakraborty <kauschluss@disroot.org>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

diff --git a/drivers/gpu/drm/bridge/samsung-dsim.c b/drivers/gpu/drm/bridge/samsung-dsim.c
index f41650ff7e1377a1e6a26571150e905d29ebafa4..49c4456ebd235a57592d534aeceb25ede6f80fd2 100644 (file)
--- a/drivers/gpu/drm/bridge/samsung-dsim.c
+++ b/drivers/gpu/drm/bridge/samsung-dsim.c
@@ -157,6 +157,11 @@
 #define DSIM_INT_RX_ECC_ERR            BIT(15)
 #define DSIM_INT_RX_CRC_ERR            BIT(14)
 
+/* DSIM_SFRCTRL */
+#define DSIM_SFR_CTRL_STAND_BY         BIT(4)
+#define DSIM_SFR_CTRL_SHADOW_UPDATE    BIT(1)
+#define DSIM_SFR_CTRL_SHADOW_EN                BIT(0)
+
 /* DSIM_FIFOCTRL */
 #define DSIM_RX_DATA_FULL              BIT(25)
 #define DSIM_RX_DATA_EMPTY             BIT(24)
@@ -257,6 +262,7 @@ enum reg_idx {
        DSIM_PKTHDR_REG,        /* Packet Header FIFO register */
        DSIM_PAYLOAD_REG,       /* Payload FIFO register */
        DSIM_RXFIFO_REG,        /* Read FIFO register */
+       DSIM_SFRCTRL_REG,       /* SFR standby and shadow control register */
        DSIM_FIFOCTRL_REG,      /* FIFO status and control register */
        DSIM_PLLCTRL_REG,       /* PLL control register */
        DSIM_PHYCTRL_REG,
@@ -1037,6 +1043,7 @@ static void samsung_dsim_set_display_mode(struct samsung_dsim *dsi)
 
 static void samsung_dsim_set_display_enable(struct samsung_dsim *dsi, bool enable)
 {
+       const struct samsung_dsim_driver_data *driver_data = dsi->driver_data;
        u32 reg;
 
        reg = samsung_dsim_read(dsi, DSIM_MDRESOL_REG);
@@ -1045,6 +1052,15 @@ static void samsung_dsim_set_display_enable(struct samsung_dsim *dsi, bool enabl
        else
                reg &= ~DSIM_MAIN_STAND_BY;
        samsung_dsim_write(dsi, DSIM_MDRESOL_REG, reg);
+
+       if (driver_data->has_sfrctrl) {
+               reg = samsung_dsim_read(dsi, DSIM_SFRCTRL_REG);
+               if (enable)
+                       reg |= DSIM_SFR_CTRL_STAND_BY;
+               else
+                       reg &= ~DSIM_SFR_CTRL_STAND_BY;
+               samsung_dsim_write(dsi, DSIM_SFRCTRL_REG, reg);
+       }
 }
 
 static int samsung_dsim_wait_for_hdr_fifo(struct samsung_dsim *dsi)

diff --git a/include/drm/bridge/samsung-dsim.h b/include/drm/bridge/samsung-dsim.h
index d7877191bad155e877b2812daeb81ac0be6f735c..f0c1e5c5ed490afe0bcfd06830f52471710b29ea 100644 (file)
--- a/include/drm/bridge/samsung-dsim.h
+++ b/include/drm/bridge/samsung-dsim.h
@@ -57,6 +57,7 @@ struct samsung_dsim_driver_data {
        unsigned int has_freqband:1;
        unsigned int has_clklane_stop:1;
        unsigned int has_broken_fifoctrl_emptyhdr:1;
+       unsigned int has_sfrctrl:1;
        unsigned int num_clks;
        unsigned int min_freq;
        unsigned int max_freq;