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 ---
Changes in v2: None
common/cmd_gpio.c | 34 +++++++++++++++++++++++++++------- 1 file changed, 27 insertions(+), 7 deletions(-)
diff --git a/common/cmd_gpio.c b/common/cmd_gpio.c index 65d6df4..7cd1ba1 100644 --- a/common/cmd_gpio.c +++ b/common/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 @@ -195,15 +195,35 @@ 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);