pinctrl: add some error checking for user interfaces
This patch can avoid kernel oops in case the mux or config
function is not supported by driver.
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Dong Aisheng <dong.aisheng@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/pinctrl/pinmux.c b/drivers/pinctrl/pinmux.c
index 8849830..c494c37 100644
--- a/drivers/pinctrl/pinmux.c
+++ b/drivers/pinctrl/pinmux.c
@@ -323,6 +323,11 @@
const unsigned *pins;
unsigned num_pins;
+ if (!pmxops) {
+ dev_err(pctldev->dev, "does not support mux function\n");
+ return -EINVAL;
+ }
+
setting->data.mux.func =
pinmux_func_name_to_selector(pctldev, map->data.mux.function);
if (setting->data.mux.func < 0)
@@ -481,11 +486,14 @@
{
struct pinctrl_dev *pctldev = s->private;
const struct pinmux_ops *pmxops = pctldev->desc->pmxops;
- unsigned nfuncs = pmxops->get_functions_count(pctldev);
+ unsigned nfuncs;
unsigned func_selector = 0;
- mutex_lock(&pinctrl_mutex);
+ if (!pmxops)
+ return 0;
+ mutex_lock(&pinctrl_mutex);
+ nfuncs = pmxops->get_functions_count(pctldev);
while (func_selector < nfuncs) {
const char *func = pmxops->get_function_name(pctldev,
func_selector);
@@ -520,6 +528,9 @@
const struct pinmux_ops *pmxops = pctldev->desc->pmxops;
unsigned i, pin;
+ if (!pmxops)
+ return 0;
+
seq_puts(s, "Pinmux settings per pin\n");
seq_puts(s, "Format: pin (name): mux_owner gpio_owner hog?\n");