Re: [PATCH v2] thinkpad_acpi: return -NODEV while operating uninitialized LEDs

Amos Kong
2013-06-08T02:19:21Z

On Fri, Jun 7, 2013 at 5:05 PM, Adam Lee <adam.lee@canonical.com> wrote:
>
> Not all 0-15 LEDs are available for all models, sometimes it's even not
> safe. This patch return -NODEV while operating uninitialized LEDs.
>
> Signed-off-by: Adam Lee <adam.lee@canonical.com>
> ---
> drivers/platform/x86/thinkpad_acpi.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c
> index 54d31c0..d2ac4e8 100644
> --- a/drivers/platform/x86/thinkpad_acpi.c
> +++ b/drivers/platform/x86/thinkpad_acpi.c
> @@ -5401,9 +5401,12 @@ static int led_write(char *buf)
> return -ENODEV;
>
> while ((cmd = next_cmd(&buf))) {
> - if (sscanf(cmd, "%d", &led) != 1 || led < 0 || led > 15)
> + if (sscanf(cmd, "%d", &led) != 1 || led < 0 || led > (TPACPI_LED_NUMLEDS -1))
> return -EINVAL;
>
> + if (!tpacpi_leds[led].led)

The .led filed might be set to '0' in led_init(), how about set the
uninitiated .led to -1? and check by "if (tpacpi_leds[led].led < 0)"

for (i = 0; i < TPACPI_LED_NUMLEDS; i++) {
if (!tpacpi_is_led_restricted(i) &&
test_bit(i, &useful_leds)) {
rc = tpacpi_init_led(i);
if (rc < 0) {
led_exit();
return rc;
- }
+ } else
+ tpacpi_leds[led].led = -1;

} else tpacpi_leds[led].led = -1;
}

> + return -ENODEV;
> +
> if (strstr(cmd, "off")) {
> s = TPACPI_LED_OFF;
> } else if (strstr(cmd, "on")) {
> --
> 1.7.10.4