Commit ee65ad0e2a9e ("backlight: pwm_bl: Avoid backlight flicker when
probed from DT") tries to dereference the device of_node pointer
unconditionally, causing a NULL pointer dereference on non-dt platforms.
Fix it by replacing the phandle variable with a node variable and
by checking that for NULL before dereferencing it.Reported-by: Robert Jarzmik <[email protected]> Signed-off-by: Philipp Zabel <[email protected]> --- drivers/video/backlight/pwm_bl.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/drivers/video/backlight/pwm_bl.c b/drivers/video/backlight/pwm_bl.c index 3daf9cc..a22c1ec 100644 --- a/drivers/video/backlight/pwm_bl.c +++ b/drivers/video/backlight/pwm_bl.c @@ -198,8 +198,8 @@ static int pwm_backlight_probe(struct platform_device *pdev) struct platform_pwm_backlight_data defdata; struct backlight_properties props; struct backlight_device *bl; + struct device_node *node = pdev->dev.of_node; struct pwm_bl_data *pb; - phandle phandle = pdev->dev.of_node->phandle; int initial_blank = FB_BLANK_UNBLANK; int ret; @@ -273,7 +273,7 @@ static int pwm_backlight_probe(struct platform_device *pdev) * assume that another driver will enable the backlight at the * appropriate time. Therefore, if it is disabled, keep it so. */ - if (phandle && + if (node && node->phandle && gpiod_get_direction(pb->enable_gpio) == GPIOF_DIR_OUT && gpiod_get_value(pb->enable_gpio) == 0) initial_blank = FB_BLANK_POWERDOWN; @@ -287,12 +287,11 @@ static int pwm_backlight_probe(struct platform_device *pdev) goto err_alloc; } - if (phandle && !regulator_is_enabled(pb->power_supply)) + if (node && node->phandle && !regulator_is_enabled(pb->power_supply)) initial_blank = FB_BLANK_POWERDOWN; pb->pwm = devm_pwm_get(&pdev->dev, NULL); - if (IS_ERR(pb->pwm) && PTR_ERR(pb->pwm) != -EPROBE_DEFER - && !pdev->dev.of_node) { + if (IS_ERR(pb->pwm) && PTR_ERR(pb->pwm) != -EPROBE_DEFER && !node) { dev_err(&pdev->dev, "unable to request PWM, trying legacy API\n"); pb->legacy = true; pb->pwm = pwm_request(data->pwm_id, "pwm-backlight"); -- 2.6.2 -- To unsubscribe from this list: send the line "unsubscribe linux-pwm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
