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davinci: mmc: add cpufreq support

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Add cpufreq support to MMC driver. The clock divider value has to be
modified according to the controller input frequency.

Signed-off-by: Chaithrika U S <chaithrika@ti.com>
Cc: Linus Walleij <linus.ml.walleij@gmail.com>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Chaithrika U S 2009-12-14 18:01:23 -08:00 committed by Linus Torvalds
parent 3d348aaf5b
commit 7e30b8decb
1 changed files with 84 additions and 16 deletions
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100
drivers/mmc/host/davinci_mmc.c
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@ -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);