pinctrl: enhance reporting of errors when loading from DT

There are a few places in the api where the code simply returns -EINVAL when
it finds an error. An example is pinmux_map_to_setting() which now reports an
error if we try to match a group with a function that it does not support.

The reporting of errors in pinconf_check_ops and pinmux_check_ops now has the
same style and is located inside the according functions and not the calling
code.

When the map is found in the DT but the default state can not be selected we
get an error to know that the code at least tried.

The patch also removes a stray word from one comment and a "->" from another
for the sake of consistency.

Finally we replace a few pr_err/debug() calls with dev_err/dbg().

Thanks go to Stephen Warren for reviewing the patch and enhancing the reporting
inside pinmux_map_to_setting().

Signed-off-by: John Crispin <blogic@openwrt.org>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

1 files changed, 8 insertions, 2 deletions

diff --git a/drivers/pinctrl/pinconf.c b/drivers/pinctrl/pinconf.c
index 14f48c96b20d..7ce139ef7e64 100644
--- a/drivers/pinctrl/pinconf.c
+++ b/drivers/pinctrl/pinconf.c
@@ -28,11 +28,17 @@ int pinconf_check_ops(struct pinctrl_dev *pctldev)
 	const struct pinconf_ops *ops = pctldev->desc->confops;
 
 	/* We must be able to read out pin status */
-	if (!ops->pin_config_get && !ops->pin_config_group_get)
+	if (!ops->pin_config_get && !ops->pin_config_group_get) {
+		dev_err(pctldev->dev,
+			"pinconf must be able to read out pin status\n");
 		return -EINVAL;
+	}
 	/* We have to be able to config the pins in SOME way */
-	if (!ops->pin_config_set && !ops->pin_config_group_set)
+	if (!ops->pin_config_set && !ops->pin_config_group_set) {
+		dev_err(pctldev->dev,
+			"pinconf has to be able to set a pins config\n");
 		return -EINVAL;
+	}
 	return 0;
 }