[bug report] drm/bridge: it6505: Adapt runtime power management framework

[bug report] drm/bridge: it6505: Adapt runtime power management framework

[Dan Carpenter]

Hello Pin-yen Lin,

The patch 10517777d302: "drm/bridge: it6505: Adapt runtime power
management framework" from Oct 4, 2022, leads to the following Smatch
static checker warning:

	drivers/gpu/drm/bridge/ite-it6505.c:2712 it6505_extcon_work()
	warn: pm_runtime_get_sync() also returns 1 on success

drivers/gpu/drm/bridge/ite-it6505.c
    2685 static void it6505_extcon_work(struct work_struct *work)
    2686 {
    2687         struct it6505 *it6505 = container_of(work, struct it6505, extcon_wq);
    2688         struct device *dev = &it6505->client->dev;
    2689         int state, ret;
    2690 
    2691         if (it6505->enable_drv_hold)
    2692                 return;
    2693 
    2694         mutex_lock(&it6505->extcon_lock);
    2695 
    2696         state = extcon_get_state(it6505->extcon, EXTCON_DISP_DP);
    2697         DRM_DEV_DEBUG_DRIVER(dev, "EXTCON_DISP_DP = 0x%02x", state);
    2698 
    2699         if (state == it6505->extcon_state || unlikely(state < 0))
    2700                 goto unlock;
    2701         it6505->extcon_state = state;
    2702         if (state) {
    2703                 DRM_DEV_DEBUG_DRIVER(dev, "start to power on");
    2704                 msleep(100);
    2705                 ret = pm_runtime_get_sync(dev);
    2706 
    2707                 /*
    2708                  * On system resume, extcon_work can be triggered before
    2709                  * pm_runtime_force_resume re-enables runtime power management.
    2710                  * Handling the error here to make sure the bridge is powered on.
    2711                  */
--> 2712                 if (ret)
    2713                         it6505_poweron(it6505);

pm_runtime_get_sync() returns 1 on success.  Consider using
pm_runtime_resume_and_get() instead.

    2714         } else {
    2715                 DRM_DEV_DEBUG_DRIVER(dev, "start to power off");
    2716                 pm_runtime_put_sync(dev);
    2717 
    2718                 drm_helper_hpd_irq_event(it6505->bridge.dev);
    2719                 memset(it6505->dpcd, 0, sizeof(it6505->dpcd));
    2720                 DRM_DEV_DEBUG_DRIVER(dev, "power off it6505 success!");
    2721         }
    2722 
    2723 unlock:
    2724         mutex_unlock(&it6505->extcon_lock);
    2725 }

regards,
dan carpenter