[PATCH 1/2] davinci: MMC: Add a function to control reset state of the controller

[PATCH 1/2] davinci: MMC: Add a function to control reset state of the controller

[Kevin Hilman]

From: Chaithrika U S <chaithrika@ti.com>

Add a helper function which will aid in changing the reset
status of the controller.

Signed-off-by: Chaithrika U S <chaithrika@ti.com>
Acked-by: Kevin Hilman <khilman@deeprootsystems.com>
---
I thought this series had made it into -mm for 2.6.34, but I guess not.
Here it is again for 2.6.35.

 drivers/mmc/host/davinci_mmc.c |   37 ++++++++++++++++---------------------
 1 files changed, 16 insertions(+), 21 deletions(-)

diff --git a/drivers/mmc/host/davinci_mmc.c b/drivers/mmc/host/davinci_mmc.c
index 547d29c..56afe0a 100644
--- a/drivers/mmc/host/davinci_mmc.c
+++ b/drivers/mmc/host/davinci_mmc.c
@@ -909,19 +909,26 @@ static void mmc_davinci_cmd_done(struct mmc_davinci_host *host,
 	}
 }
 
-static void
-davinci_abort_data(struct mmc_davinci_host *host, struct mmc_data *data)
+static inline void mmc_davinci_reset_ctrl(struct mmc_davinci_host *host,
+								int val)
 {
 	u32 temp;
 
-	/* reset command and data state machines */
 	temp = readl(host->base + DAVINCI_MMCCTL);
-	writel(temp | MMCCTL_CMDRST | MMCCTL_DATRST,
-		host->base + DAVINCI_MMCCTL);
+	if (val)	/* reset */
+		temp |= MMCCTL_CMDRST | MMCCTL_DATRST;
+	else		/* enable */
+		temp &= ~(MMCCTL_CMDRST | MMCCTL_DATRST);
 
-	temp &= ~(MMCCTL_CMDRST | MMCCTL_DATRST);
-	udelay(10);
 	writel(temp, host->base + DAVINCI_MMCCTL);
+	udelay(10);
+}
+
+static void
+davinci_abort_data(struct mmc_davinci_host *host, struct mmc_data *data)
+{
+	mmc_davinci_reset_ctrl(host, 1);
+	mmc_davinci_reset_ctrl(host, 0);
 }
 
 static irqreturn_t mmc_davinci_irq(int irq, void *dev_id)
@@ -1125,15 +1132,8 @@ 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 */
-	writel(readl(host->base + DAVINCI_MMCCTL) | MMCCTL_DATRST,
-		host->base + DAVINCI_MMCCTL);
-
-	/* CMD line portion is diabled and in reset state */
-	writel(readl(host->base + DAVINCI_MMCCTL) | MMCCTL_CMDRST,
-		host->base + DAVINCI_MMCCTL);
 
-	udelay(10);
+	mmc_davinci_reset_ctrl(host, 1);
 
 	writel(0, host->base + DAVINCI_MMCCLK);
 	writel(MMCCLK_CLKEN, host->base + DAVINCI_MMCCLK);
@@ -1141,12 +1141,7 @@ static void __init init_mmcsd_host(struct mmc_davinci_host *host)
 	writel(0x1FFF, host->base + DAVINCI_MMCTOR);
 	writel(0xFFFF, host->base + DAVINCI_MMCTOD);
 
-	writel(readl(host->base + DAVINCI_MMCCTL) & ~MMCCTL_DATRST,
-		host->base + DAVINCI_MMCCTL);
-	writel(readl(host->base + DAVINCI_MMCCTL) & ~MMCCTL_CMDRST,
-		host->base + DAVINCI_MMCCTL);
-
-	udelay(10);
+	mmc_davinci_reset_ctrl(host, 0);
 }
 
 static int __init davinci_mmcsd_probe(struct platform_device *pdev)
-- 
1.7.0.2

[PATCH 2/2] davinci: MMC: updates to suspend/resume implementation

[Kevin Hilman]

From: Chaithrika U S <chaithrika@ti.com>

Improve the suspend and resume callbacks in DaVinci MMC host controller driver.
Modify the reset status of the contorller and clock during suspend and resume.
Also migrate the power management callbacks from platform driver to dev_pm_ops
structure.

Tested on DA850/OMAP-L138 EVM.

Signed-off-by: Chaithrika U S <chaithrika@ti.com>
Acked-by: Kevin Hilman <khilman@deeprootsystems.com>
---
I thought this series had made it into -mm for 2.6.34, but I guess not.
Here it is again for 2.6.35.

 drivers/mmc/host/davinci_mmc.c |   51 +++++++++++++++++++++++++++++++++------
 1 files changed, 43 insertions(+), 8 deletions(-)

diff --git a/drivers/mmc/host/davinci_mmc.c b/drivers/mmc/host/davinci_mmc.c
index 56afe0a..e4d1591 100644
--- a/drivers/mmc/host/davinci_mmc.c
+++ b/drivers/mmc/host/davinci_mmc.c
@@ -171,6 +171,7 @@ struct mmc_davinci_host {
 #define DAVINCI_MMC_DATADIR_READ	1
 #define DAVINCI_MMC_DATADIR_WRITE	2
 	unsigned char data_dir;
+	unsigned char suspended;
 
 	/* buffer is used during PIO of one scatterlist segment, and
 	 * is updated along with buffer_bytes_left.  bytes_left applies
@@ -1332,32 +1333,66 @@ static int __exit davinci_mmcsd_remove(struct platform_device *pdev)
 }
 
 #ifdef CONFIG_PM
-static int davinci_mmcsd_suspend(struct platform_device *pdev, pm_message_t msg)
+static int davinci_mmcsd_suspend(struct device *dev)
 {
+	struct platform_device *pdev = to_platform_device(dev);
 	struct mmc_davinci_host *host = platform_get_drvdata(pdev);
+	struct pm_message msg = { PM_EVENT_SUSPEND };
+	int ret;
 
-	return mmc_suspend_host(host->mmc, msg);
+	mmc_host_enable(host->mmc);
+	ret = mmc_suspend_host(host->mmc, msg);
+	if (!ret) {
+		writel(0, host->base + DAVINCI_MMCIM);
+		mmc_davinci_reset_ctrl(host, 1);
+		mmc_host_disable(host->mmc);
+		clk_disable(host->clk);
+		host->suspended = 1;
+	} else {
+		host->suspended = 0;
+		mmc_host_disable(host->mmc);
+	}
+
+	return ret;
 }
 
-static int davinci_mmcsd_resume(struct platform_device *pdev)
+static int davinci_mmcsd_resume(struct device *dev)
 {
+	struct platform_device *pdev = to_platform_device(dev);
 	struct mmc_davinci_host *host = platform_get_drvdata(pdev);
+	int ret;
 
-	return mmc_resume_host(host->mmc);
+	if (!host->suspended)
+		return 0;
+
+	clk_enable(host->clk);
+	mmc_host_enable(host->mmc);
+
+	mmc_davinci_reset_ctrl(host, 0);
+	ret = mmc_resume_host(host->mmc);
+	if (!ret)
+		host->suspended = 0;
+
+	return ret;
 }
+
+static struct dev_pm_ops davinci_mmcsd_pm = {
+	.suspend        = davinci_mmcsd_suspend,
+	.resume         = davinci_mmcsd_resume,
+};
+
+#define davinci_mmcsd_pm_ops (&davinci_mmcsd_pm)
 #else
-#define davinci_mmcsd_suspend	NULL
-#define davinci_mmcsd_resume	NULL
+#define davinci_mmcsd_pm_ops NULL
 #endif
 
 static struct platform_driver davinci_mmcsd_driver = {
 	.driver		= {
 		.name	= "davinci_mmc",
 		.owner	= THIS_MODULE,
+		.pm	= davinci_mmcsd_pm_ops,
 	},
 	.remove		= __exit_p(davinci_mmcsd_remove),
-	.suspend	= davinci_mmcsd_suspend,
-	.resume		= davinci_mmcsd_resume,
 };
 
 static int __init davinci_mmcsd_init(void)
-- 
1.7.0.2

Re: [PATCH 2/2] davinci: MMC: updates to suspend/resume implementation

[Andrew Morton]

On Tue, 16 Mar 2010 13:30:25 -0700
Kevin Hilman <khilman@deeprootsystems.com> wrote:

> +static struct dev_pm_ops davinci_mmcsd_pm = {
> +	.suspend        = davinci_mmcsd_suspend,
> +	.resume         = davinci_mmcsd_resume,
> +};

checkpatch said

WARNING: struct dev_pm_ops should normally be const
#83: FILE: drivers/mmc/host/davinci_mmc.c:1379:
+static struct dev_pm_ops davinci_mmcsd_pm = {

I'll make that change.  Please check.