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>

2 files changed, 52 insertions, 48 deletions

diff --git a/drivers/mmc/host/msm_sdcc.c b/drivers/mmc/host/msm_sdcc.c
index 524858597901..591ef3c4e9a7 100644
--- a/drivers/mmc/host/msm_sdcc.c
+++ b/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;
@@ -60,29 +60,42 @@ static unsigned int msmsdcc_sdioirq;
 #define CMD_SPINMAX 20
 
 
-static inline int
-msmsdcc_enable_clocks(struct msmsdcc_host *host, int enable)
+static inline void 
+msmsdcc_disable_clocks(struct msmsdcc_host *host, int deferr)
 {
-        int rc;
+        WARN_ON(!host->clks_on);
 
-        WARN_ON(enable == host->clks_on);
-        if (enable) {
-                rc = clk_enable(host->pclk);
-                if (rc)
-                        return rc;
-                rc = clk_enable(host->clk);
-                if (rc) {
-                        clk_disable(host->pclk);
-                        return rc;
-                }
-                udelay(1 + ((3 * USEC_PER_SEC) /
-                       (host->clk_rate ? host->clk_rate : msmsdcc_fmin)));
-                host->clks_on = 1;
+        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 rc;
+
+        WARN_ON(host->clks_on);
+
+        del_timer_sync(&host->busclk_timer);
+
+        rc = clk_enable(host->pclk);
+        if (rc)
+                return rc;
+        rc = clk_enable(host->clk);
+        if (rc) {
+                clk_disable(host->pclk);
+                return rc;
+        }
+        udelay(1 + ((3 * USEC_PER_SEC) /
+               (host->clk_rate ? host->clk_rate : msmsdcc_fmin)));
+        host->clks_on = 1;
         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;
 }
diff --git a/drivers/mmc/host/msm_sdcc.h b/drivers/mmc/host/msm_sdcc.h
index 361cb6efd248..da0039c9285e 100644
--- a/drivers/mmc/host/msm_sdcc.h
+++ b/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 */