OMAP: DSS2: DSI: wait for TXCLKESC domain to come out of reset

Add dsi_cio_wait_tx_clk_esc_reset() function which waits for the
TXCLKESC domains to come out of reset.

Things have worked fine without this, but better be safe than sorry.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

1 files changed, 65 insertions, 0 deletions

diff --git a/drivers/video/omap2/dss/dsi.c b/drivers/video/omap2/dss/dsi.c
index f4219628444..8bc443bae6b 100644
--- a/drivers/video/omap2/dss/dsi.c
+++ b/drivers/video/omap2/dss/dsi.c
@@ -1969,6 +1969,65 @@ static void dsi_cio_disable_lane_override(void)
         REG_FLD_MOD(DSI_DSIPHY_CFG10, 0, 22, 17); /* REGLPTXSCPDAT4TO0DXDY */
 }
 
+static int dsi_cio_wait_tx_clk_esc_reset(struct omap_dss_device *dssdev)
+{
+        int t;
+        int bits[3];
+        bool in_use[3];
+
+        if (dss_has_feature(FEAT_DSI_REVERSE_TXCLKESC)) {
+                bits[0] = 28;
+                bits[1] = 27;
+                bits[2] = 26;
+        } else {
+                bits[0] = 24;
+                bits[1] = 25;
+                bits[2] = 26;
+        }
+
+        in_use[0] = false;
+        in_use[1] = false;
+        in_use[2] = false;
+
+        if (dssdev->phy.dsi.clk_lane != 0)
+                in_use[dssdev->phy.dsi.clk_lane - 1] = true;
+        if (dssdev->phy.dsi.data1_lane != 0)
+                in_use[dssdev->phy.dsi.data1_lane - 1] = true;
+        if (dssdev->phy.dsi.data2_lane != 0)
+                in_use[dssdev->phy.dsi.data2_lane - 1] = true;
+
+        t = 100000;
+        while (true) {
+                u32 l;
+                int i;
+                int ok;
+
+                l = dsi_read_reg(DSI_DSIPHY_CFG5);
+
+                ok = 0;
+                for (i = 0; i < 3; ++i) {
+                        if (!in_use[i] || (l & (1 << bits[i])))
+                                ok++;
+                }
+
+                if (ok == 3)
+                        break;
+
+                if (--t == 0) {
+                        for (i = 0; i < 3; ++i) {
+                                if (!in_use[i] || (l & (1 << bits[i])))
+                                        continue;
+
+                                DSSERR("CIO TXCLKESC%d domain not coming " \
+                                                "out of reset\n", i);
+                        }
+                        return -EIO;
+                }
+        }
+
+        return 0;
+}
+
 static int dsi_cio_init(struct omap_dss_device *dssdev)
 {
         int r;
@@ -2028,6 +2087,10 @@ static int dsi_cio_init(struct omap_dss_device *dssdev)
         dsi_if_enable(false);
         REG_FLD_MOD(DSI_CLK_CTRL, 1, 20, 20); /* LP_CLK_ENABLE */
 
+        r = dsi_cio_wait_tx_clk_esc_reset(dssdev);
+        if (r)
+                goto err_tx_clk_esc_rst;
+
         if (dsi.ulps_enabled) {
                 /* Keep Mark-1 state for 1ms (as per DSI spec) */
                 ktime_t wait = ns_to_ktime(1000 * 1000);
@@ -2050,6 +2113,8 @@ static int dsi_cio_init(struct omap_dss_device *dssdev)
 
         return 0;
 
+err_tx_clk_esc_rst:
+        REG_FLD_MOD(DSI_CLK_CTRL, 0, 20, 20); /* LP_CLK_ENABLE */
 err_cio_pwr_dom:
         dsi_cio_power(DSI_COMPLEXIO_POWER_OFF);
 err_cio_pwr: