diff options
author | San Mehat <san@google.com> | 2009-12-03 18:58:54 (GMT) |
---|---|---|
committer | Daniel Walker <dwalker@codeaurora.org> | 2010-03-18 20:37:23 (GMT) |
commit | d0719e59f4ad96616f7c02ef0201667e41778c88 (patch) | |
tree | 51c30578d5942737d549700c5c28a3d200340d4d /drivers/mmc/host/msm_sdcc.c | |
parent | 6ac9ea69069804d357064357d0082b0eab4c87ce (diff) | |
download | linux-d0719e59f4ad96616f7c02ef0201667e41778c88.tar.xz |
mmc: msm_sdcc: Fix issue where clocks could be disabled mid transaction
msmsdcc_enable_clocks() was incorrectly being called depending on
the state of host->clks_on. This means the busclk idle timer was never
being deleted if the clock was already on.. Bogus.
Also fixes a possible double clk disable if the call to
del_timer_sync() in msmsdcc_disable_clocks() raced with
the busclk timer.
Signed-off-by: San Mehat <san@google.com>
Signed-off-by: Daniel Walker <dwalker@codeaurora.org>
Diffstat (limited to 'drivers/mmc/host/msm_sdcc.c')
-rw-r--r-- | drivers/mmc/host/msm_sdcc.c | 61 |
1 files changed, 27 insertions, 34 deletions
diff --git a/drivers/mmc/host/msm_sdcc.c b/drivers/mmc/host/msm_sdcc.c index 8329fd6..47b1f25 100644 --- a/drivers/mmc/host/msm_sdcc.c +++ b/drivers/mmc/host/msm_sdcc.c @@ -61,7 +61,7 @@ static unsigned int msmsdcc_sdioirq; #define CMD_SPINMAX 20 -static inline void +static inline void msmsdcc_disable_clocks(struct msmsdcc_host *host, int deferr) { WARN_ON(!host->clks_on); @@ -72,9 +72,14 @@ msmsdcc_disable_clocks(struct msmsdcc_host *host, int deferr) mod_timer(&host->busclk_timer, jiffies + BUSCLK_TIMEOUT); } else { del_timer_sync(&host->busclk_timer); - clk_disable(host->clk); - clk_disable(host->pclk); - host->clks_on = 0; + /* Need to check clks_on again in case the busclk + * timer fired + */ + if (host->clks_on) { + clk_disable(host->clk); + clk_disable(host->pclk); + host->clks_on = 0; + } } } @@ -83,21 +88,21 @@ 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; + if (!host->clks_on) { + 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; } - udelay(1 + ((3 * USEC_PER_SEC) / - (host->clk_rate ? host->clk_rate : msmsdcc_fmin))); - host->clks_on = 1; return 0; } @@ -180,7 +185,8 @@ msmsdcc_dma_exec_func(struct msm_dmov_cmd *cmd) struct msmsdcc_host *host = (struct msmsdcc_host *)cmd->data; msmsdcc_writel(host, host->cmd_timeout, MMCIDATATIMER); - msmsdcc_writel(host, (unsigned int)host->curr.xfer_size, MMCIDATALENGTH); + msmsdcc_writel(host, (unsigned int)host->curr.xfer_size, + MMCIDATALENGTH); msmsdcc_writel(host, host->cmd_pio_irqmask, MMCIMASK1); msmsdcc_writel(host, host->cmd_datactrl, MMCIDATACTRL); @@ -854,13 +860,7 @@ msmsdcc_request(struct mmc_host *mmc, struct mmc_request *mrq) return; } - /* 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); - spin_lock_irqsave(&host->lock, flags); + msmsdcc_enable_clocks(host); host->curr.mrq = mrq; @@ -893,11 +893,10 @@ msmsdcc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) int rc; unsigned long flags; - if (!host->clks_on) - msmsdcc_enable_clocks(host); - spin_lock_irqsave(&host->lock, flags); + msmsdcc_enable_clocks(host); + if (ios->clock) { if (ios->clock != host->clk_rate) { rc = clk_set_rate(host->clk, ios->clock); @@ -1026,13 +1025,9 @@ static void msmsdcc_busclk_expired(unsigned long _data) { struct msmsdcc_host *host = (struct msmsdcc_host *) _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_disable_clocks(host, 0); - spin_unlock_irqrestore(&host->lock, flags); } static int @@ -1324,10 +1319,8 @@ msmsdcc_suspend(struct platform_device *dev, pm_message_t state) if (mmc->card && mmc->card->type != MMC_TYPE_SDIO) rc = mmc_suspend_host(mmc, state); - if (!rc) { + if (!rc) msmsdcc_writel(host, 0, MMCIMASK0); - - } if (host->clks_on) msmsdcc_disable_clocks(host, 0); } |