[PATCH] gpio: aspeed: Don't attempt to debounce if disabled

From: Joel Stanley
Date: Tue May 02 2017 - 02:08:46 EST

We warn the user at driver probe time that debouncing is disabled.
However, if they request debouncing later on we print a confusing error

gpio_aspeed 1e780000.gpio: Failed to convert 5000us to cycles at 0Hz: -524

Instead bail out when the clock is not present.

Fixes: 5ae4cb94b3133 (gpio: aspeed: Add debounce support)
Signed-off-by: Joel Stanley <joel@xxxxxxxxx>
drivers/gpio/gpio-aspeed.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/gpio/gpio-aspeed.c b/drivers/gpio/gpio-aspeed.c
index ccea609676ee..4ca436e66bdb 100644
--- a/drivers/gpio/gpio-aspeed.c
+++ b/drivers/gpio/gpio-aspeed.c
@@ -646,6 +646,9 @@ static int enable_debounce(struct gpio_chip *chip, unsigned int offset,
int rc;
int i;

+ if (!gpio->clk)
+ return -EINVAL;
rc = usecs_to_cycles(gpio, usecs, &requested_cycles);
if (rc < 0) {
dev_warn(chip->parent, "Failed to convert %luus to cycles at %luHz: %d\n",