From 4adbbcc7b6cfb3dcf5ab49b06edb7752391b0e80 Mon Sep 17 00:00:00 2001 From: San Mehat Date: Sun, 8 Nov 2009 13:00:37 -0800 Subject: mmc: msm_sdcc: Clean up clock management and add a 10us delay after enabling clocks It appears that in some cases there may be a delay on the ARM9 in enabling our clock. As a result, we may put the controller into a bad state. Delay 10us after enabling clocks to let the peripheral settle. Note - this is all imperical. Also ensure set_ios() callback grabs the host lock. Signed-off-by: San Mehat Signed-off-by: Daniel Walker --- drivers/mmc/host/msm_sdcc.c | 80 ++++++++++++++++++++++----------------------- 1 file changed, 40 insertions(+), 40 deletions(-) (limited to 'drivers/mmc') diff --git a/drivers/mmc/host/msm_sdcc.c b/drivers/mmc/host/msm_sdcc.c index 4c068e5fe6b2..977932a4bf4b 100644 --- a/drivers/mmc/host/msm_sdcc.c +++ b/drivers/mmc/host/msm_sdcc.c @@ -735,20 +735,42 @@ msmsdcc_request(struct mmc_host *mmc, struct mmc_request *mrq) spin_unlock_irqrestore(&host->lock, flags); } +static int inline +msmsdcc_enable_clocks(struct msmsdcc_host *host, int enable) +{ + int rc; + if (enable) { + rc = clk_enable(host->pclk); + if (rc) + return rc; + rc = clk_enable(host->clk); + if (rc) { + clk_disable(host->pclk); + return rc; + } + host->clks_on = 1; + udelay(10); + } else { + clk_disable(host->clk); + clk_disable(host->pclk); + host->clks_on = 0; + } + return 0; +} + static void msmsdcc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) { struct msmsdcc_host *host = mmc_priv(mmc); u32 clk = 0, pwr = 0; int rc; + unsigned long flags; + spin_lock_irqsave(&host->lock, flags); if (ios->clock) { - if (!host->clks_on) { - clk_enable(host->pclk); - clk_enable(host->clk); - host->clks_on = 1; - } + if (!host->clks_on) + msmsdcc_enable_clocks(host, 1); if (ios->clock != host->clk_rate) { rc = clk_set_rate(host->clk, ios->clock); if (rc < 0) @@ -793,11 +815,9 @@ msmsdcc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) writel(pwr, host->base + MMCIPOWER); } - if (!(clk & MCI_CLK_ENABLE) && host->clks_on) { - clk_disable(host->clk); - clk_disable(host->pclk); - host->clks_on = 0; - } + if (!(clk & MCI_CLK_ENABLE) && host->clks_on) + msmsdcc_enable_clocks(host, 0); + spin_unlock_irqrestore(&host->lock, flags); } static void msmsdcc_enable_sdio_irq(struct mmc_host *mmc, int enable) @@ -899,7 +919,6 @@ msmsdcc_command_expired(unsigned long _data) pr_err("%s: Command timeout (%p %p %p %p)\n", mmc_hostname(host->mmc), mrq, mrq->cmd, mrq->data, host->dma.sg); - mrq->cmd->error = -ETIMEDOUT; msmsdcc_stop_data(host); @@ -1031,31 +1050,21 @@ msmsdcc_probe(struct platform_device *pdev) */ msmsdcc_init_dma(host); - /* - * Setup main peripheral bus clock - */ + /* Get our clocks */ host->pclk = clk_get(&pdev->dev, "sdc_pclk"); if (IS_ERR(host->pclk)) { ret = PTR_ERR(host->pclk); goto host_free; } - ret = clk_enable(host->pclk); - if (ret) - goto pclk_put; - - host->pclk_rate = clk_get_rate(host->pclk); - - /* - * Setup SDC MMC clock - */ host->clk = clk_get(&pdev->dev, "sdc_clk"); if (IS_ERR(host->clk)) { ret = PTR_ERR(host->clk); - goto pclk_disable; + goto pclk_put; } - ret = clk_enable(host->clk); + /* Enable clocks */ + ret = msmsdcc_enable_clocks(host, 1); if (ret) goto clk_put; @@ -1065,10 +1074,9 @@ msmsdcc_probe(struct platform_device *pdev) goto clk_disable; } + host->pclk_rate = clk_get_rate(host->pclk); host->clk_rate = clk_get_rate(host->clk); - host->clks_on = 1; - /* * Setup MMC host structure */ @@ -1187,11 +1195,9 @@ msmsdcc_probe(struct platform_device *pdev) if (host->stat_irq) free_irq(host->stat_irq, host); clk_disable: - clk_disable(host->clk); + msmsdcc_enable_clocks(host, 0); clk_put: clk_put(host->clk); - pclk_disable: - clk_disable(host->pclk); pclk_put: clk_put(host->pclk); host_free: @@ -1217,11 +1223,8 @@ msmsdcc_suspend(struct platform_device *dev, pm_message_t state) if (!rc) { writel(0, host->base + MMCIMASK0); - if (host->clks_on) { - clk_disable(host->clk); - clk_disable(host->pclk); - host->clks_on = 0; - } + if (host->clks_on) + msmsdcc_enable_clocks(host, 0); } } return rc; @@ -1238,11 +1241,8 @@ msmsdcc_resume(struct platform_device *dev) spin_lock_irqsave(&host->lock, flags); - if (!host->clks_on) { - clk_enable(host->pclk); - clk_enable(host->clk); - host->clks_on = 1; - } + if (!host->clks_on) + msmsdcc_enable_clocks(host, 1); writel(host->saved_irq0mask, host->base + MMCIMASK0); -- cgit v1.2.3