drm/bridge/sii8620: simplify hardware reset procedure

There is no need to flip reset pin twice. Also delays can be changed to
values present in vendor's code.

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Maciej Purski <m.purski@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180608060457.18357-1-a.hajda@samsung.com
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Change-Id: Ib7710bedc9f5dbdd448262d44f83c2c80c208ac5

diff --git a/drivers/gpu/drm/bridge/sil-sii8620.c b/drivers/gpu/drm/bridge/sil-sii8620.c
index dc29237b348601cdc112d7c44ba29d1199981cbd..2884876d46de7fb70aecb3bd9eddf395db01cfcc 100644 (file)
--- a/drivers/gpu/drm/bridge/sil-sii8620.c
+++ b/drivers/gpu/drm/bridge/sil-sii8620.c
@@ -980,8 +980,17 @@ static int sii8620_hw_on(struct sii8620 *ctx)
        ret = regulator_bulk_enable(ARRAY_SIZE(ctx->supplies), ctx->supplies);
        if (ret)
                return ret;
+
        usleep_range(10000, 20000);
-       return clk_prepare_enable(ctx->clk_xtal);
+       ret = clk_prepare_enable(ctx->clk_xtal);
+       if (ret)
+               return ret;
+
+       msleep(100);
+       gpiod_set_value(ctx->gpio_reset, 0);
+       msleep(100);
+
+       return 0;
 }
 
 static int sii8620_hw_off(struct sii8620 *ctx)
@@ -991,17 +1000,6 @@ static int sii8620_hw_off(struct sii8620 *ctx)
        return regulator_bulk_disable(ARRAY_SIZE(ctx->supplies), ctx->supplies);
 }
 
-static void sii8620_hw_reset(struct sii8620 *ctx)
-{
-       usleep_range(10000, 20000);
-       gpiod_set_value(ctx->gpio_reset, 0);
-       usleep_range(5000, 20000);
-       gpiod_set_value(ctx->gpio_reset, 1);
-       usleep_range(10000, 20000);
-       gpiod_set_value(ctx->gpio_reset, 0);
-       msleep(300);
-}
-
 static void sii8620_cbus_reset(struct sii8620 *ctx)
 {
        sii8620_write(ctx, REG_PWD_SRST, BIT_PWD_SRST_CBUS_RST
@@ -2121,7 +2119,6 @@ static void sii8620_cable_in(struct sii8620 *ctx)
                dev_err(dev, "Error powering on, %d.\n", ret);
                return;
        }
-       sii8620_hw_reset(ctx);
 
        sii8620_read_buf(ctx, REG_VND_IDL, ver, ARRAY_SIZE(ver));
        ret = sii8620_clear_error(ctx);