drm/bridge: ti-sn65dsi86: Check the regmap return value when setting a GPIO

The ti_sn_bridge_gpio_set() got the return value of
regmap_update_bits() but didn't check it.  The function can't return
an error value, but we should at least print a warning if it didn't
work.

This fixes a compiler warning about setting "ret" but not using it.

Fixes: 27ed2b3f22ed ("drm/bridge: ti-sn65dsi86: Export bridge GPIOs to Linux")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200612123003.v2.4.Ia4376fd88cdc6e8f8b43c65548458305f82f1d61@changeid

diff --git a/drivers/gpu/drm/bridge/ti-sn65dsi86.c b/drivers/gpu/drm/bridge/ti-sn65dsi86.c
index 1080e4f9df96d20a5b6a6709a2fbf3457d9d3fe9..bd3eb0a097327d265136ef8faf9d1b21d8cd0092 100644 (file)
--- a/drivers/gpu/drm/bridge/ti-sn65dsi86.c
+++ b/drivers/gpu/drm/bridge/ti-sn65dsi86.c
@@ -999,6 +999,9 @@ static void ti_sn_bridge_gpio_set(struct gpio_chip *chip, unsigned int offset,
        ret = regmap_update_bits(pdata->regmap, SN_GPIO_IO_REG,
                                 BIT(SN_GPIO_OUTPUT_SHIFT + offset),
                                 val << (SN_GPIO_OUTPUT_SHIFT + offset));
+       if (ret)
+               dev_warn(pdata->dev,
+                        "Failed to set bridge GPIO %u: %d\n", offset, ret);
 }
 
 static int ti_sn_bridge_gpio_direction_input(struct gpio_chip *chip,