summaryrefslogtreecommitdiff
path: root/cmd/gpio.c
diff options
context:
space:
mode:
authorSimon Glass <sjg@chromium.org>2015-08-31 18:55:36 -0600
committerSimon Glass <sjg@chromium.org>2016-03-17 21:27:37 -0600
commitb71bea71294959c07e67ce7c91594f380f82f3a9 (patch)
treec78d4f31fbb91a6ff5760d610b67b6ba19b7418f /cmd/gpio.c
parentf23baa572f96e1e13d7f1a3c8addb61b5d0dbd29 (diff)
gpio: Report errors when GPIOs cannot be read
Some controllers do not allow the output value to be read. Detect this and report the error in that case. Signed-off-by: Simon Glass <sjg@chromium.org>
Diffstat (limited to 'cmd/gpio.c')
-rw-r--r--cmd/gpio.c34
1 files changed, 27 insertions, 7 deletions
diff --git a/cmd/gpio.c b/cmd/gpio.c
index 693998e8bd..ecdc453918 100644
--- a/cmd/gpio.c
+++ b/cmd/gpio.c
@@ -119,7 +119,7 @@ static int do_gpio(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
unsigned int gpio;
enum gpio_cmd sub_cmd;
- ulong value;
+ int value;
const char *str_cmd, *str_gpio = NULL;
int ret;
#ifdef CONFIG_DM_GPIO
@@ -197,15 +197,35 @@ static int do_gpio(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
value = gpio_get_value(gpio);
} else {
switch (sub_cmd) {
- case GPIO_SET: value = 1; break;
- case GPIO_CLEAR: value = 0; break;
- case GPIO_TOGGLE: value = !gpio_get_value(gpio); break;
- default: goto show_usage;
+ case GPIO_SET:
+ value = 1;
+ break;
+ case GPIO_CLEAR:
+ value = 0;
+ break;
+ case GPIO_TOGGLE:
+ value = gpio_get_value(gpio);
+ if (!IS_ERR_VALUE(value))
+ value = !value;
+ break;
+ default:
+ goto show_usage;
}
gpio_direction_output(gpio, value);
}
- printf("gpio: pin %s (gpio %i) value is %lu\n",
- str_gpio, gpio, value);
+ printf("gpio: pin %s (gpio %i) value is ", str_gpio, gpio);
+ if (IS_ERR_VALUE(value))
+ printf("unknown (ret=%d)\n", value);
+ else
+ printf("%d\n", value);
+ if (sub_cmd != GPIO_INPUT && !IS_ERR_VALUE(value)) {
+ int nval = gpio_get_value(gpio);
+
+ if (IS_ERR_VALUE(nval))
+ printf(" Warning: no access to GPIO output value\n");
+ else if (nval != value)
+ printf(" Warning: value of pin is still %d\n", nval);
+ }
if (ret != -EBUSY)
gpio_free(gpio);