Input: pmic8xxx-pwrkey - set sane default for debounce time

If the debounce time is 0 our usage of ilog2() later on in this driver will
cause undefined behavior. If CONFIG_OF=n this fact is evident to the
compiler, and it emits a call to ____ilog2_NaN() which doesn't exist. Fix
this by setting a sane default for debounce and failing to probe if
debounce is 0 in the DT.

Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

diff --git a/drivers/input/misc/pmic8xxx-pwrkey.c b/drivers/input/misc/pmic8xxx-pwrkey.c
index 1cb8fda..c91e3d3 100644 (file)
--- a/drivers/input/misc/pmic8xxx-pwrkey.c
+++ b/drivers/input/misc/pmic8xxx-pwrkey.c
@@ -92,15 +92,15 @@ static int pmic8xxx_pwrkey_probe(struct platform_device *pdev)
        bool pull_up;
 
        if (of_property_read_u32(pdev->dev.of_node, "debounce", &kpd_delay))
-               kpd_delay = 0;
+               kpd_delay = 15625;
 
-       pull_up = of_property_read_bool(pdev->dev.of_node, "pull-up");
-
-       if (kpd_delay > 62500) {
+       if (kpd_delay > 62500 || kpd_delay == 0) {
                dev_err(&pdev->dev, "invalid power key trigger delay\n");
                return -EINVAL;
        }
 
+       pull_up = of_property_read_bool(pdev->dev.of_node, "pull-up");
+
        regmap = dev_get_regmap(pdev->dev.parent, NULL);
        if (!regmap) {
                dev_err(&pdev->dev, "failed to locate regmap for the device\n");