Add cpufreq support to MMC driver. The clock dividervalue has to be modified according to the controller input frequency.
Signed-off-by: Chaithrika U S <chaithr...@ti.com> --- This patch applies to DaVinci GIT tree as the driver is not yet present in Linus' tree. drivers/mmc/host/davinci_mmc.c | 100 +++++++++++++++++++++++++++++++++------ 1 files changed, 84 insertions(+), 16 deletions(-) diff --git a/drivers/mmc/host/davinci_mmc.c b/drivers/mmc/host/davinci_mmc.c index 6c76f64..dd45e7c 100644 --- a/drivers/mmc/host/davinci_mmc.c +++ b/drivers/mmc/host/davinci_mmc.c @@ -25,6 +25,7 @@ #include <linux/platform_device.h> #include <linux/clk.h> #include <linux/err.h> +#include <linux/cpufreq.h> #include <linux/mmc/host.h> #include <linux/io.h> #include <linux/irq.h> @@ -200,6 +201,9 @@ struct mmc_davinci_host { u8 version; /* for ns in one cycle calculation */ unsigned ns_in_one_cycle; +#ifdef CONFIG_CPU_FREQ + struct notifier_block freq_transition; +#endif }; @@ -739,27 +743,12 @@ static unsigned int calculate_freq_for_card(struct mmc_davinci_host *host, return mmc_push_pull_divisor; } -static void mmc_davinci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) +static void calculate_clk_divider(struct mmc_host *mmc, struct mmc_ios *ios) { unsigned int open_drain_freq = 0, mmc_pclk = 0; unsigned int mmc_push_pull_freq = 0; struct mmc_davinci_host *host = mmc_priv(mmc); - mmc_pclk = host->mmc_input_clk; - dev_dbg(mmc_dev(host->mmc), - "clock %dHz busmode %d powermode %d Vdd %04x\n", - ios->clock, ios->bus_mode, ios->power_mode, - ios->vdd); - if (ios->bus_width == MMC_BUS_WIDTH_4) { - dev_dbg(mmc_dev(host->mmc), "Enabling 4 bit mode\n"); - writel(readl(host->base + DAVINCI_MMCCTL) | MMCCTL_WIDTH_4_BIT, - host->base + DAVINCI_MMCCTL); - } else { - dev_dbg(mmc_dev(host->mmc), "Disabling 4 bit mode\n"); - writel(readl(host->base + DAVINCI_MMCCTL) & ~MMCCTL_WIDTH_4_BIT, - host->base + DAVINCI_MMCCTL); - } - if (ios->bus_mode == MMC_BUSMODE_OPENDRAIN) { u32 temp; @@ -798,6 +787,29 @@ static void mmc_davinci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) udelay(10); } +} + +static void mmc_davinci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) +{ + unsigned int mmc_pclk = 0; + struct mmc_davinci_host *host = mmc_priv(mmc); + + mmc_pclk = host->mmc_input_clk; + dev_dbg(mmc_dev(host->mmc), + "clock %dHz busmode %d powermode %d Vdd %04x\n", + ios->clock, ios->bus_mode, ios->power_mode, + ios->vdd); + if (ios->bus_width == MMC_BUS_WIDTH_4) { + dev_dbg(mmc_dev(host->mmc), "Enabling 4 bit mode\n"); + writel(readl(host->base + DAVINCI_MMCCTL) | MMCCTL_WIDTH_4_BIT, + host->base + DAVINCI_MMCCTL); + } else { + dev_dbg(mmc_dev(host->mmc), "Disabling 4 bit mode\n"); + writel(readl(host->base + DAVINCI_MMCCTL) & ~MMCCTL_WIDTH_4_BIT, + host->base + DAVINCI_MMCCTL); + } + + calculate_clk_divider(mmc, ios); host->bus_mode = ios->bus_mode; if (ios->power_mode == MMC_POWER_UP) { @@ -1040,6 +1052,52 @@ static struct mmc_host_ops mmc_davinci_ops = { /*----------------------------------------------------------------------*/ +#ifdef CONFIG_CPU_FREQ +static int mmc_davinci_cpufreq_transition(struct notifier_block *nb, + unsigned long val, void *data) +{ + struct mmc_davinci_host *host; + unsigned int mmc_pclk; + struct mmc_host *mmc; + unsigned long flags; + + host = container_of(nb, struct mmc_davinci_host, freq_transition); + mmc = host->mmc; + mmc_pclk = clk_get_rate(host->clk); + + if (val == CPUFREQ_POSTCHANGE) { + spin_lock_irqsave(&mmc->lock, flags); + host->mmc_input_clk = mmc_pclk; + calculate_clk_divider(mmc, &mmc->ios); + spin_unlock_irqrestore(&mmc->lock, flags); + } + + return 0; +} + +static inline int mmc_davinci_cpufreq_register(struct mmc_davinci_host *host) +{ + host->freq_transition.notifier_call = mmc_davinci_cpufreq_transition; + + return cpufreq_register_notifier(&host->freq_transition, + CPUFREQ_TRANSITION_NOTIFIER); +} + +static inline void mmc_davinci_cpufreq_deregister(struct mmc_davinci_host *host) +{ + cpufreq_unregister_notifier(&host->freq_transition, + CPUFREQ_TRANSITION_NOTIFIER); +} +#else +static inline int mmc_davinci_cpufreq_register(struct mmc_davinci_host *host) +{ + return 0; +} + +static inline void mmc_davinci_cpufreq_deregister(struct mmc_davinci_host *host) +{ +} +#endif static void __init init_mmcsd_host(struct mmc_davinci_host *host) { /* DAT line portion is diabled and in reset state */ @@ -1169,6 +1227,12 @@ static int __init davinci_mmcsd_probe(struct platform_device *pdev) platform_set_drvdata(pdev, host); + ret = mmc_davinci_cpufreq_register(host); + if (ret) { + dev_err(&pdev->dev, "failed to register cpufreq\n"); + goto cpu_freq_fail; + } + ret = mmc_add_host(mmc); if (ret < 0) goto out; @@ -1186,6 +1250,8 @@ static int __init davinci_mmcsd_probe(struct platform_device *pdev) return 0; out: + mmc_davinci_cpufreq_deregister(host); +cpu_freq_fail: if (host) { davinci_release_dma_channels(host); @@ -1215,6 +1281,8 @@ static int __exit davinci_mmcsd_remove(struct platform_device *pdev) platform_set_drvdata(pdev, NULL); if (host) { + mmc_davinci_cpufreq_deregister(host); + mmc_remove_host(host->mmc); free_irq(host->irq, host); -- 1.5.6 _______________________________________________ Davinci-linux-open-source mailing list Davinci-linux-open-source@linux.davincidsp.com http://linux.davincidsp.com/mailman/listinfo/davinci-linux-open-source