mmc: msm_sdcc: Fix bug where busclk expiry timer was not properly disabled

Signed-off-by: San Mehat <san@google.com>
Signed-off-by: Daniel Walker <dwalker@codeaurora.org>

drivers/mmc/host/msm_sdcc.c

@@ -48,7 +48,7 @@
 
 #define DRIVER_NAME "msm-sdcc"
 
-#define BUSCLK_TIMEOUT (HZ * 5)
+#define BUSCLK_TIMEOUT (HZ)
 static unsigned int msmsdcc_fmin = 144000;
 static unsigned int msmsdcc_fmax = 50000000;
 static unsigned int msmsdcc_4bit = 1;
@@ -60,13 +60,31 @@ static unsigned int msmsdcc_sdioirq;
 #define CMD_SPINMAX 20
 
 
+static inline void 
+msmsdcc_disable_clocks(struct msmsdcc_host *host, int deferr)
+{
+	WARN_ON(!host->clks_on);
+
+	if (deferr) {
+		mod_timer(&host->busclk_timer, jiffies + BUSCLK_TIMEOUT);
+	} else {
+		del_timer_sync(&host->busclk_timer);
+//		dev_info(mmc_dev(host->mmc), "Immediate clock shutdown\n");
+		clk_disable(host->clk);
+		clk_disable(host->pclk);
+		host->clks_on = 0;
+	}
+}
+
 static inline int
-msmsdcc_enable_clocks(struct msmsdcc_host *host, int enable)
+msmsdcc_enable_clocks(struct msmsdcc_host *host)
 {
 	int rc;
 
-	WARN_ON(enable == host->clks_on);
-	if (enable) {
+	WARN_ON(host->clks_on);
+
+	del_timer_sync(&host->busclk_timer);
+
 	rc = clk_enable(host->pclk);
 	if (rc)
 		return rc;
@@ -78,11 +96,6 @@ msmsdcc_enable_clocks(struct msmsdcc_host *host, int enable)
 	udelay(1 + ((3 * USEC_PER_SEC) /
 	       (host->clk_rate ? host->clk_rate : msmsdcc_fmin)));
 	host->clks_on = 1;
-	} else {
-		clk_disable(host->clk);
-		clk_disable(host->pclk);
-		host->clks_on = 0;
-	}
 	return 0;
 }
 
@@ -118,8 +131,7 @@ msmsdcc_request_end(struct msmsdcc_host *host, struct mmc_request *mrq)
 	if (mrq->cmd->error == -ETIMEDOUT)
 		mdelay(5);
 
-	if (host->use_bustimer)
-		mod_timer(&host->busclk_timer, jiffies + BUSCLK_TIMEOUT);
+	msmsdcc_disable_clocks(host, 1);
 	/*
 	 * Need to drop the host lock here; mmc_request_done may call
 	 * back into the driver...
@@ -240,12 +252,12 @@ msmsdcc_dma_complete_func(struct msm_dmov_cmd *cmd,
 		if (!mrq->data->error)
 			host->curr.data_xfered = host->curr.xfer_size;
 		if (!mrq->data->stop || mrq->cmd->error) {
-			msmsdcc_writel(host, 0, MMCICOMMAND);
 			host->curr.mrq = NULL;
 			host->curr.cmd = NULL;
 			mrq->data->bytes_xfered = host->curr.data_xfered;
 
 			spin_unlock_irqrestore(&host->lock, flags);
+			msmsdcc_disable_clocks(host, 1);
 			mmc_request_done(host->mmc, mrq);
 			return;
 		} else
@@ -835,8 +847,14 @@ msmsdcc_request(struct mmc_host *mmc, struct mmc_request *mrq)
 	}
 
 	host->curr.mrq = mrq;
+
+	/* Need to drop the host lock here in case
+	 * the busclk wd fires 
+	 */
+	spin_unlock_irqrestore(&host->lock, flags);
 	if (!host->clks_on)
-		msmsdcc_enable_clocks(host, 1);
+		msmsdcc_enable_clocks(host);
+	spin_lock_irqsave(&host->lock, flags);
 
 	if (mrq->data && mrq->data->flags & MMC_DATA_READ)
 		/* Queue/read data, daisy-chain command when data starts */
@@ -867,9 +885,10 @@ msmsdcc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 	int rc;
 	unsigned long flags;
 
-	spin_lock_irqsave(&host->lock, flags);
 	if (!host->clks_on)
-		msmsdcc_enable_clocks(host, 1);
+		msmsdcc_enable_clocks(host);
+
+	spin_lock_irqsave(&host->lock, flags);
 
 	if (ios->clock) {
 		if (ios->clock != host->clk_rate) {
@@ -915,8 +934,7 @@ msmsdcc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 		host->pwr = pwr;
 		msmsdcc_writel(host, pwr, MMCIPOWER);
 	}
-	if (host->clks_on)
-		msmsdcc_enable_clocks(host, 0);
+	msmsdcc_disable_clocks(host, 1);
 	spin_unlock_irqrestore(&host->lock, flags);
 }
 
@@ -1001,9 +1019,9 @@ msmsdcc_busclk_expired(unsigned long _data)
 	unsigned long 		flags;
 
 	spin_lock_irqsave(&host->lock, flags);
+	dev_info(mmc_dev(host->mmc), "Bus clock timer expired\n");
 	if (host->clks_on)
-		msmsdcc_enable_clocks(host, 0);
-
+		msmsdcc_disable_clocks(host, 0);
 	spin_unlock_irqrestore(&host->lock, flags);
 }
 
@@ -1110,8 +1128,6 @@ msmsdcc_probe(struct platform_device *pdev)
 
 	host->cmdpoll = 1;
 
-	host->use_bustimer = 1;
-
 	host->base = ioremap(memres->start, PAGE_SIZE);
 	if (!host->base) {
 		ret = -ENOMEM;
@@ -1143,7 +1159,7 @@ msmsdcc_probe(struct platform_device *pdev)
 	}
 
 	/* Enable clocks */
-	ret = msmsdcc_enable_clocks(host, 1);
+	ret = msmsdcc_enable_clocks(host);
 	if (ret)
 		goto clk_put;
 
@@ -1263,8 +1279,7 @@ msmsdcc_probe(struct platform_device *pdev)
 	if (host->timer.function)
 		pr_info("%s: Polling status mode enabled\n", mmc_hostname(mmc));
 
-	if (host->use_bustimer)
-		mod_timer(&host->busclk_timer, jiffies + BUSCLK_TIMEOUT);
+	msmsdcc_disable_clocks(host, 1);
 	return 0;
  cmd_irq_free:
 	free_irq(cmd_irqres->start, host);
@@ -1272,7 +1287,7 @@ msmsdcc_probe(struct platform_device *pdev)
 	if (host->stat_irq)
 		free_irq(host->stat_irq, host);
  clk_disable:
-	msmsdcc_enable_clocks(host, 0);
+	msmsdcc_disable_clocks(host, 0);
  clk_put:
 	clk_put(host->clk);
  pclk_put:
@@ -1293,8 +1308,6 @@ msmsdcc_suspend(struct platform_device *dev, pm_message_t state)
 	if (mmc) {
 		struct msmsdcc_host *host = mmc_priv(mmc);
 
-		if (host->use_bustimer)
-			del_timer_sync(&host->busclk_timer);
 		spin_lock_irqsave(&host->lock, flags);
 		if (host->stat_irq)
 			disable_irq(host->stat_irq);
@@ -1304,10 +1317,10 @@ msmsdcc_suspend(struct platform_device *dev, pm_message_t state)
 		if (!rc) {
 			msmsdcc_writel(host, 0, MMCIMASK0);
 
-			if (host->clks_on)
-				msmsdcc_enable_clocks(host, 0);
 		}
 		spin_unlock_irqrestore(&host->lock, flags);
+		if (host->clks_on)
+			msmsdcc_disable_clocks(host, 0);
 	}
 	return rc;
 }
@@ -1316,27 +1329,19 @@ static int
 msmsdcc_resume(struct platform_device *dev)
 {
 	struct mmc_host *mmc = mmc_get_drvdata(dev);
-	unsigned long flags;
 
 	if (mmc) {
 		struct msmsdcc_host *host = mmc_priv(mmc);
 
-		spin_lock_irqsave(&host->lock, flags);
-
-		if (!host->clks_on)
-			msmsdcc_enable_clocks(host, 1);
-
-		if (host->use_bustimer)
-			mod_timer(&host->busclk_timer, jiffies + BUSCLK_TIMEOUT);
+		msmsdcc_enable_clocks(host);
 
 		msmsdcc_writel(host, host->saved_irq0mask, MMCIMASK0);
 
-		spin_unlock_irqrestore(&host->lock, flags);
-
 		if (mmc->card && mmc->card->type != MMC_TYPE_SDIO)
 			mmc_resume_host(mmc);
 		if (host->stat_irq)
 			enable_irq(host->stat_irq);
+		msmsdcc_disable_clocks(host, 1);
 	}
 	return 0;
 }

drivers/mmc/host/msm_sdcc.h

@@ -215,7 +215,6 @@ struct msmsdcc_host {
 	struct clk		*pclk;		/* SDCC peripheral bus clock */
 	unsigned int		clks_on;	/* set if clocks are enabled */
 	struct timer_list	busclk_timer;
-	int			use_bustimer;
 
 	unsigned int		eject;		/* eject state */