drm/sun4i: tcon: Reduce the scope of the LVDS error a bit

The current logic to deal with old DT missing the LVDS properties doesn't
take into account whether the LVDS output is supported in the first place,
resulting in spurious error messages on SoCs where it doesn't even matter.

Introduce a new TCON flag to list if LVDS is supported at all to prevent
this from happening.

Reviewed-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180221125703.4595-1-maxime.ripard@bootlin.com

diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c b/drivers/gpu/drm/sun4i/sun4i_tcon.c
index ade197b1a9ac67aa51d3235fdb9e2a340d1da4fb..2de586b7c98b58ea4d03470f720744840d3a026f 100644 (file)
--- a/drivers/gpu/drm/sun4i/sun4i_tcon.c
+++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c
@@ -875,52 +875,56 @@ static int sun4i_tcon_bind(struct device *dev, struct device *master,
                return ret;
        }
 
-       /*
-        * This can only be made optional since we've had DT nodes
-        * without the LVDS reset properties.
-        *
-        * If the property is missing, just disable LVDS, and print a
-        * warning.
-        */
-       tcon->lvds_rst = devm_reset_control_get_optional(dev, "lvds");
-       if (IS_ERR(tcon->lvds_rst)) {
-               dev_err(dev, "Couldn't get our reset line\n");
-               return PTR_ERR(tcon->lvds_rst);
-       } else if (tcon->lvds_rst) {
-               has_lvds_rst = true;
-               reset_control_reset(tcon->lvds_rst);
-       } else {
-               has_lvds_rst = false;
-       }
+       if (tcon->quirks->supports_lvds) {
+               /*
+                * This can only be made optional since we've had DT
+                * nodes without the LVDS reset properties.
+                *
+                * If the property is missing, just disable LVDS, and
+                * print a warning.
+                */
+               tcon->lvds_rst = devm_reset_control_get_optional(dev, "lvds");
+               if (IS_ERR(tcon->lvds_rst)) {
+                       dev_err(dev, "Couldn't get our reset line\n");
+                       return PTR_ERR(tcon->lvds_rst);
+               } else if (tcon->lvds_rst) {
+                       has_lvds_rst = true;
+                       reset_control_reset(tcon->lvds_rst);
+               } else {
+                       has_lvds_rst = false;
+               }
 
-       /*
-        * This can only be made optional since we've had DT nodes
-        * without the LVDS reset properties.
-        *
-        * If the property is missing, just disable LVDS, and print a
-        * warning.
-        */
-       if (tcon->quirks->has_lvds_alt) {
-               tcon->lvds_pll = devm_clk_get(dev, "lvds-alt");
-               if (IS_ERR(tcon->lvds_pll)) {
-                       if (PTR_ERR(tcon->lvds_pll) == -ENOENT) {
-                               has_lvds_alt = false;
+               /*
+                * This can only be made optional since we've had DT
+                * nodes without the LVDS reset properties.
+                *
+                * If the property is missing, just disable LVDS, and
+                * print a warning.
+                */
+               if (tcon->quirks->has_lvds_alt) {
+                       tcon->lvds_pll = devm_clk_get(dev, "lvds-alt");
+                       if (IS_ERR(tcon->lvds_pll)) {
+                               if (PTR_ERR(tcon->lvds_pll) == -ENOENT) {
+                                       has_lvds_alt = false;
+                               } else {
+                                       dev_err(dev, "Couldn't get the LVDS PLL\n");
+                                       return PTR_ERR(tcon->lvds_pll);
+                               }
                        } else {
-                               dev_err(dev, "Couldn't get the LVDS PLL\n");
-                               return PTR_ERR(tcon->lvds_pll);
+                               has_lvds_alt = true;
                        }
-               } else {
-                       has_lvds_alt = true;
                }
-       }
 
-       if (!has_lvds_rst || (tcon->quirks->has_lvds_alt && !has_lvds_alt)) {
-               dev_warn(dev,
-                        "Missing LVDS properties, Please upgrade your DT\n");
-               dev_warn(dev, "LVDS output disabled\n");
-               can_lvds = false;
+               if (!has_lvds_rst ||
+                   (tcon->quirks->has_lvds_alt && !has_lvds_alt)) {
+                       dev_warn(dev, "Missing LVDS properties, Please upgrade your DT\n");
+                       dev_warn(dev, "LVDS output disabled\n");
+                       can_lvds = false;
+               } else {
+                       can_lvds = true;
+               }
        } else {
-               can_lvds = true;
+               can_lvds = false;
        }
 
        ret = sun4i_tcon_init_clocks(dev, tcon);
@@ -1139,7 +1143,7 @@ static const struct sun4i_tcon_quirks sun8i_a33_quirks = {
 };
 
 static const struct sun4i_tcon_quirks sun8i_a83t_lcd_quirks = {
-       /* nothing is supported */
+       .supports_lvds          = true,
 };
 
 static const struct sun4i_tcon_quirks sun8i_v3s_quirks = {

diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.h b/drivers/gpu/drm/sun4i/sun4i_tcon.h
index b761c7b823c560536b0f44a3c6eab6337d3e32d7..278700c7bf9f6f71ec3c85686c81919362aa40fa 100644 (file)
--- a/drivers/gpu/drm/sun4i/sun4i_tcon.h
+++ b/drivers/gpu/drm/sun4i/sun4i_tcon.h
@@ -175,6 +175,7 @@ struct sun4i_tcon_quirks {
        bool    has_channel_1;  /* a33 does not have channel 1 */
        bool    has_lvds_alt;   /* Does the LVDS clock have a parent other than the TCON clock? */
        bool    needs_de_be_mux; /* sun6i needs mux to select backend */
+       bool    supports_lvds;   /* Does the TCON support an LVDS output? */
 
        /* callback to handle tcon muxing options */
        int     (*set_mux)(struct sun4i_tcon *, const struct drm_encoder *);