OMAPDSS: DSI: wait for hsdiv clocks when enabling PLL
authorTomi Valkeinen <tomi.valkeinen@ti.com>
Mon, 4 Aug 2014 10:46:05 +0000 (13:46 +0300)
committerTomi Valkeinen <tomi.valkeinen@ti.com>
Wed, 12 Nov 2014 11:40:19 +0000 (13:40 +0200)
At the moment we have two functions to wait for the HSDIV clocks to get
active, dsi_wait_pll_hsdiv_dispc_active and
dsi_wait_pll_hsdiv_dsi_active. Instead of such inconvenient functions,
let's just make sure that the hsdiv clocks are active after the pll has
been enabled.

This patch adds code to dsi_pll_set_clock_div() to wait until HSDIV
clocks are active.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
drivers/video/fbdev/omap2/dss/dsi.c

index 0793bc67a275864ece56a4a8605553c5535704ea..fe8196b17a5e46712a95b0aba9f9ba04b17e81d7 100644 (file)
@@ -1514,6 +1514,20 @@ static void dsi_pll_calc_dsi_fck(struct dsi_clock_info *cinfo)
        cinfo->dsi_pll_hsdiv_dsi_clk = cinfo->clkin4ddr / cinfo->regm_dsi;
 }
 
+static int dsi_wait_hsdiv_ack(struct platform_device *dsidev, u32 hsdiv_ack_mask)
+{
+       int t = 100;
+
+       while (t-- > 0) {
+               u32 v = dsi_read_reg(dsidev, DSI_PLL_STATUS);
+               v &= hsdiv_ack_mask;
+               if (v == hsdiv_ack_mask)
+                       return 0;
+       }
+
+       return -ETIMEDOUT;
+}
+
 int dsi_pll_set_clock_div(struct platform_device *dsidev,
                struct dsi_clock_info *cinfo)
 {
@@ -1646,6 +1660,13 @@ int dsi_pll_set_clock_div(struct platform_device *dsidev,
        l = FLD_MOD(l, 0, 20, 20);      /* DSI_HSDIVBYPASS */
        dsi_write_reg(dsidev, DSI_PLL_CONFIGURATION2, l);
 
+       r = dsi_wait_hsdiv_ack(dsidev, BIT(7) | BIT(8));
+       if (r) {
+               DSSERR("failed to enable HSDIV clocks: %d\n", r);
+               goto err;
+       }
+
+
        DSSDBG("PLL config done\n");
 err:
        return r;