Merge "msm_serial_hs: wait for clock-off to complete before shutdown" (5c024bb5) · Commits · e / devices / android_kernel_sony_msm8994

drivers/tty/serial/msm_serial_hs.c

+45 −18

Original line number	Diff line number	Diff line
		@@ -336,6 +336,7 @@ static int msm_hs_clock_vote(struct msm_hs_port *msm_uport)
		{
		int rc = 0;

		mutex_lock(&msm_uport->clk_mutex);
		if (1 == atomic_inc_return(&msm_uport->clk_count)) {
		msm_hs_bus_voting(msm_uport, BUS_SCALING);
		/* Turn on core clk and iface clk */
		@@ -345,6 +346,7 @@ static int msm_hs_clock_vote(struct msm_hs_port *msm_uport)
		dev_err(msm_uport->uport.dev,
		"%s: Could not turn on pclk [%d]\n",
		__func__, rc);
		mutex_unlock(&msm_uport->clk_mutex);
		return rc;
		}
		}
		@@ -355,11 +357,13 @@ static int msm_hs_clock_vote(struct msm_hs_port *msm_uport)
		"%s: Could not turn on core clk [%d]\n",
		__func__, rc);
		clk_disable_unprepare(msm_uport->pclk);
		mutex_unlock(&msm_uport->clk_mutex);
		return rc;
		}
		msm_uport->clk_state = MSM_HS_CLK_ON;
		MSM_HS_DBG("%s: Clock ON successful\n", __func__);
		}
		mutex_unlock(&msm_uport->clk_mutex);


		return rc;
		@@ -376,6 +380,7 @@ static void msm_hs_clock_unvote(struct msm_hs_port *msm_uport)
		return;
		}

		mutex_lock(&msm_uport->clk_mutex);
		rc = atomic_dec_return(&msm_uport->clk_count);
		if (0 == rc) {
		/* Turn off the core clk and iface clk*/
		@@ -387,6 +392,7 @@ static void msm_hs_clock_unvote(struct msm_hs_port *msm_uport)
		msm_uport->clk_state = MSM_HS_CLK_OFF;
		MSM_HS_DBG("%s: Clock OFF successful\n", __func__);
		}
		mutex_unlock(&msm_uport->clk_mutex);
		}

		/* Check if the uport line number matches with user id stored in pdata.
		@@ -1821,8 +1827,6 @@ static int msm_hs_check_clock_off(struct uart_port *uport)
		if (msm_uport->clk_state != MSM_HS_CLK_REQUEST_OFF \|\|
		!uart_circ_empty(tx_buf) \|\| msm_uport->tx.dma_in_flight \|\|
		msm_uport->imr_reg & UARTDM_ISR_TXLEV_BMSK) {
		spin_unlock_irqrestore(&uport->lock, flags);
		mutex_unlock(&msm_uport->clk_mutex);
		if (msm_uport->clk_state == MSM_HS_CLK_REQUEST_OFF) {
		msm_uport->clk_state = MSM_HS_CLK_ON;
		/* Pulling RFR line high */
		@@ -1833,6 +1837,8 @@ static int msm_hs_check_clock_off(struct uart_port *uport)
		msm_hs_write(uport, UART_DM_MR1, data);
		mb();
		}
		spin_unlock_irqrestore(&uport->lock, flags);
		mutex_unlock(&msm_uport->clk_mutex);
		MSM_HS_DBG("%s(): clkstate %d", __func__, msm_uport->clk_state);
		return -1;
		}
		@@ -1870,7 +1876,9 @@ static int msm_hs_check_clock_off(struct uart_port *uport)
		mb();

		/* we really want to clock off */
		mutex_unlock(&msm_uport->clk_mutex);
		msm_hs_clock_unvote(msm_uport);
		mutex_lock(&msm_uport->clk_mutex);

		spin_lock_irqsave(&uport->lock, flags);
		if (use_low_power_wakeup(msm_uport)) {
		@@ -2091,7 +2099,9 @@ void msm_hs_request_clock_on(struct uart_port *uport)
		}
		spin_unlock_irqrestore(&uport->lock, flags);

		mutex_unlock(&msm_uport->clk_mutex);
		ret = msm_hs_clock_vote(msm_uport);
		mutex_lock(&msm_uport->clk_mutex);
		if (ret) {
		MSM_HS_INFO("Clock ON Failure"
		"For UART CLK Stalling HSUART\n");
		@@ -2106,8 +2116,10 @@ void msm_hs_request_clock_on(struct uart_port *uport)
		spin_unlock_irqrestore(&uport->lock, flags);
		MSM_HS_DBG("%s:Calling wait forxcompletion\n",
		__func__);
		mutex_unlock(&msm_uport->clk_mutex);
		ret = wait_event_timeout(msm_uport->bam_disconnect_wait,
		msm_uport->rx.flush == FLUSH_SHUTDOWN, 300);
		mutex_lock(&msm_uport->clk_mutex);
		if (!ret)
		MSM_HS_ERR("BAM Disconnect not happened\n");
		spin_lock_irqsave(&uport->lock, flags);
		@@ -3180,8 +3192,25 @@ static void msm_hs_shutdown(struct uart_port *uport)
		struct msm_hs_tx *tx = &msm_uport->tx;
		struct sps_pipe *sps_pipe_handle = tx->cons.pipe_handle;

		MSM_HS_INFO("%s()\n", __func__);
		msm_hs_clock_vote(msm_uport);
		/*
		* cancel the hrtimer first so that
		* clk_state can not change in flight
		*/
		hrtimer_cancel(&msm_uport->clk_off_timer);
		flush_work(&msm_uport->clock_off_w);

		if (use_low_power_wakeup(msm_uport))
		irq_set_irq_wake(msm_uport->wakeup.irq, 0);

		/* wake irq or uart irq is active depending on clk_state */
		if (msm_uport->clk_state == MSM_HS_CLK_OFF) {
		if (use_low_power_wakeup(msm_uport))
		disable_irq(msm_uport->wakeup.irq);
		} else {
		disable_irq(uport->irq);
		wake_unlock(&msm_uport->dma_wake_lock);
		}

		/* make sure tx tasklet finishes */
		tasklet_kill(&msm_uport->tx.tlet);
		ret = wait_event_timeout(msm_uport->tx.wait,
		@@ -3189,21 +3218,20 @@ static void msm_hs_shutdown(struct uart_port *uport)
		if (!ret)
		MSM_HS_WARN("Shutdown called when tx buff not empty");

		/* BAM Disconnect for TX */
		ret = sps_disconnect(sps_pipe_handle);
		if (ret)
		MSM_HS_ERR("%s(): sps_disconnect failed\n",
		__func__);
		/* make sure rx tasklet finishes */
		tasklet_kill(&msm_uport->rx.tlet);
		wait_event(msm_uport->rx.wait, msm_uport->rx.flush == FLUSH_SHUTDOWN);
		cancel_delayed_work_sync(&msm_uport->rx.flip_insert_work);
		flush_workqueue(msm_uport->hsuart_wq);
		WARN_ON(msm_uport->rx.flush < FLUSH_STOP);
		pm_runtime_disable(uport->dev);
		msm_uport->rx.buffer_pending = NONE_PENDING;
		MSM_HS_DBG("%s(): tx, rx events complete", __func__);

		msm_hs_clock_vote(msm_uport);
		mutex_lock(&msm_uport->clk_mutex);
		/* BAM Disconnect for TX */
		ret = sps_disconnect(sps_pipe_handle);
		if (ret)
		MSM_HS_ERR("%s(): sps_disconnect failed\n",
		__func__);
		WARN_ON(msm_uport->rx.flush < FLUSH_STOP);
		/* Disable the transmitter */
		msm_hs_write(uport, UART_DM_CR, UARTDM_CR_TX_DISABLE_BMSK);
		/* Disable the receiver */
		@@ -3216,22 +3244,21 @@ static void msm_hs_shutdown(struct uart_port *uport)
		* Hence mb() requires here.
		*/
		mb();
		mutex_unlock(&msm_uport->clk_mutex);

		hrtimer_cancel(&msm_uport->clk_off_timer);
		msm_uport->rx.buffer_pending = NONE_PENDING;
		MSM_HS_DBG("%s(): tx, rx events complete", __func__);
		msm_hs_clock_unvote(msm_uport);
		if (msm_uport->clk_state != MSM_HS_CLK_OFF) {
		/* to balance clk_state */
		msm_hs_clock_unvote(msm_uport);
		wake_unlock(&msm_uport->dma_wake_lock);
		}

		pm_runtime_disable(uport->dev);
		msm_uport->clk_state = MSM_HS_CLK_PORT_OFF;
		dma_unmap_single(uport->dev, msm_uport->tx.dma_base,
		UART_XMIT_SIZE, DMA_TO_DEVICE);

		if (use_low_power_wakeup(msm_uport))
		irq_set_irq_wake(msm_uport->wakeup.irq, 0);

		/* Free the interrupt */
		free_irq(uport->irq, msm_uport);
		if (use_low_power_wakeup(msm_uport))