Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit c721d237 authored by Ingrid Gallardo's avatar Ingrid Gallardo
Browse files

msm: mdss: fix extra refcount in the mdp clock during clock gate 



There is a race condition between kickoff and early
wakeup events; add mutex to protect the state of the
resources and prevent race condition.

Change-Id: Ibf3284f1d1fce26b88ea0a1f56f42a4682b16c77
Signed-off-by: default avatarIngrid Gallardo <ingridg@codeaurora.org>
parent 88333add

drivers/video/msm/mdss/mdss_mdp.h

+1 −0
Original line number Diff line number Diff line
@@ -291,6 +291,7 @@ struct mdss_mdp_ctl { 
	struct mutex offlock;

	struct mutex flush_lock;

	struct mutex *shared_lock;

	struct mutex rsrc_lock;

	spinlock_t spin_lock;



	struct mdss_panel_data *panel_data;

drivers/video/msm/mdss/mdss_mdp_ctl.c

+1 −0
Original line number Diff line number Diff line
@@ -1993,6 +1993,7 @@ struct mdss_mdp_ctl *mdss_mdp_ctl_alloc(struct mdss_data_type *mdata, 
			mutex_init(&ctl->lock);

			mutex_init(&ctl->offlock);

			mutex_init(&ctl->flush_lock);

			mutex_init(&ctl->rsrc_lock);

			spin_lock_init(&ctl->spin_lock);

			BLOCKING_INIT_NOTIFIER_HEAD(&ctl->notifier_head);

			pr_debug("alloc ctl_num=%d\n", ctl->num);

drivers/video/msm/mdss/mdss_mdp_intf_cmd.c

+16 −8
Original line number Diff line number Diff line
@@ -520,6 +520,7 @@ int mdss_mdp_resource_control(struct mdss_mdp_ctl *ctl, u32 sw_event) 
					__func__);

		}



		mutex_lock(&ctl->rsrc_lock);

		/* Transition OFF->ON || GATE->ON (enable clocks) */

		if ((mdp5_data->resources_state == MDP_RSRC_CTL_STATE_OFF) ||

			(mdp5_data->resources_state ==
@@ -565,6 +566,7 @@ int mdss_mdp_resource_control(struct mdss_mdp_ctl *ctl, u32 sw_event) 
				__func__, get_sw_event_name(sw_event));

			BUG();

		}

		mutex_unlock(&ctl->rsrc_lock);

		break;

	case MDP_RSRC_CTL_EVENT_PP_DONE:

		if (mdp5_data->resources_state != MDP_RSRC_CTL_STATE_ON) {
@@ -652,6 +654,7 @@ int mdss_mdp_resource_control(struct mdss_mdp_ctl *ctl, u32 sw_event) 
					__func__);

		}



		mutex_lock(&ctl->rsrc_lock);

		if ((mdp5_data->resources_state == MDP_RSRC_CTL_STATE_ON) ||

				(mdp5_data->resources_state

				== MDP_RSRC_CTL_STATE_GATE)) {
@@ -679,6 +682,7 @@ int mdss_mdp_resource_control(struct mdss_mdp_ctl *ctl, u32 sw_event) 
			/* update the state, now we are in off */

			mdp5_data->resources_state = MDP_RSRC_CTL_STATE_OFF;

		}

		mutex_unlock(&ctl->rsrc_lock);

		break;

	case MDP_RSRC_CTL_EVENT_EARLY_WAKE_UP:

		/*
@@ -689,6 +693,7 @@ int mdss_mdp_resource_control(struct mdss_mdp_ctl *ctl, u32 sw_event) 
		 * 3. If the current state is POWER-OFF, Schedule a work item to

		 *    POWER-ON.

		 */

		mutex_lock(&ctl->rsrc_lock);

		if (mdp5_data->resources_state != MDP_RSRC_CTL_STATE_OFF) {

			if (cancel_work_sync(&ctx->gate_clk_work))

				pr_debug("%s: %s - gate_work cancelled\n",
@@ -715,7 +720,6 @@ int mdss_mdp_resource_control(struct mdss_mdp_ctl *ctl, u32 sw_event) 
				mdss_mdp_cmd_clk_on(sctx);



			mdp5_data->resources_state = MDP_RSRC_CTL_STATE_ON;



			/*

			 * Schedule off work after cmd mode idle timeout is

			 * reached. This is to prevent the case where early wake
@@ -724,6 +728,7 @@ int mdss_mdp_resource_control(struct mdss_mdp_ctl *ctl, u32 sw_event) 
			schedule_delayed_work(&ctx->delayed_off_clk_work,

				      CMD_MODE_IDLE_TIMEOUT);

		}

		mutex_unlock(&ctl->rsrc_lock);

		break;

	default:

		pr_warn("%s unexpected event (%d)\n", __func__, sw_event);
@@ -970,16 +975,13 @@ static void clk_ctrl_delayed_off_work(struct work_struct *work) 
		mutex_lock(&cmd_clk_mtx);

	}



	mutex_lock(&ctl->rsrc_lock);



	/* Enable clocks if Gate feature is enabled and we are in this state */

	if (mdata->enable_gate) {

		/* clocks are gated at this time */

	if (mdata->enable_gate && (mdp5_data->resources_state

			== MDP_RSRC_CTL_STATE_GATE))

		mdss_mdp_clk_ctrl(MDP_BLOCK_POWER_ON);



		if (mdp5_data->resources_state

			!= MDP_RSRC_CTL_STATE_GATE)

			pr_debug("%s: enter off from ON state\n", __func__);

	}



	/* first power off the slave DSI  (if present) */

	if (sctx)

		mdss_mdp_cmd_clk_off(sctx);
@@ -996,6 +998,8 @@ static void clk_ctrl_delayed_off_work(struct work_struct *work) 
	/* update state machine that power off transition is done */

	mdp5_data->resources_state = MDP_RSRC_CTL_STATE_OFF;



	mutex_unlock(&ctl->rsrc_lock);



	/* do this at the end, so we can also protect the global power state*/

	if (ctl->mfd->split_mode == MDP_DUAL_LM_DUAL_DISPLAY)

		mutex_unlock(&cmd_clk_mtx);
@@ -1052,6 +1056,8 @@ static void clk_ctrl_gate_work(struct work_struct *work) 
		mutex_lock(&cmd_clk_mtx);

	}



	mutex_lock(&ctl->rsrc_lock);



	/* First gate the DSI clocks for the slave controller (if present) */

	if (sctx)

		mdss_mdp_ctl_intf_event
@@ -1069,6 +1075,8 @@ static void clk_ctrl_gate_work(struct work_struct *work) 
	/* update state machine that gate transition is done */

	mdp5_data->resources_state = MDP_RSRC_CTL_STATE_GATE;



	mutex_unlock(&ctl->rsrc_lock);



	/* unlock mutex needed for split display */

	if (ctl->mfd->split_mode == MDP_DUAL_LM_DUAL_DISPLAY)

		mutex_unlock(&cmd_clk_mtx);