Merge "msm: mdss: fix race condition between vsync handler and ctl_stop"

	if (!ctl)

		return -ENODEV;

	if (!ctl->ops.add_vsync_handler || !ctl->ops.remove_vsync_handler)

		return -EOPNOTSUPP;

	mutex_lock(&mdp5_data->ov_lock);

	if (!ctl->ops.add_vsync_handler || !ctl->ops.remove_vsync_handler) {

		rc = -EOPNOTSUPP;

		pr_err_once("fb%d vsync handlers are not registered\n",

			mfd->index);

		goto end;

	}

	if (!ctl->panel_data->panel_info.cont_splash_enabled

		&& (!mdss_mdp_ctl_is_power_on(ctl) ||

		mdss_panel_is_power_on_ulp(ctl->power_state))) {

		pr_debug("fb%d vsync pending first update en=%d\n",

				mfd->index, en);

		return -EPERM;

		pr_debug("fb%d vsync pending first update en=%d, ctl power state:%d\n",

				mfd->index, en, ctl->power_state);

		rc = -EPERM;

		goto end;

	}

	pr_debug("fb%d vsync en=%d\n", mfd->index, en);

	mutex_lock(&mdp5_data->ov_lock);

	mdss_mdp_clk_ctrl(MDP_BLOCK_POWER_ON);

	if (en)

		rc = ctl->ops.add_vsync_handler(ctl, &ctl->vsync_handler);

	else

		rc = ctl->ops.remove_vsync_handler(ctl, &ctl->vsync_handler);

	mdss_mdp_clk_ctrl(MDP_BLOCK_POWER_OFF);

	mutex_unlock(&mdp5_data->ov_lock);

end:

	mutex_unlock(&mdp5_data->ov_lock);

	return rc;

}