[PATCH v3 5/5] OMAP: I2C: Convert i2c driver to use PM runtime api's

Rajendra Nayak rnayak at ti.com
Tue Sep 21 10:07:16 EDT 2010


This patch converts the i2c driver to use PM runtime apis

Signed-off-by: Rajendra Nayak <rnayak at ti.com>
Cc: Kevin Hilman <khilman at deeprootsystems.com>
Cc: Paul Walmsley <paul at pwsan.com>
---
 drivers/i2c/busses/i2c-omap.c |   67 +++++++++++++----------------------------
 1 files changed, 21 insertions(+), 46 deletions(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 7674efb..126bde9 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -39,6 +39,7 @@
 #include <linux/io.h>
 #include <linux/slab.h>
 #include <linux/i2c-omap.h>
+#include <linux/pm_runtime.h>
 
 /* I2C controller revisions */
 #define OMAP_I2C_REV_2			0x20
@@ -175,8 +176,6 @@ struct omap_i2c_dev {
 	void __iomem		*base;		/* virtual */
 	int			irq;
 	int			reg_shift;      /* bit shift for I2C register addresses */
-	struct clk		*iclk;		/* Interface clock */
-	struct clk		*fclk;		/* Functional clock */
 	struct completion	cmd_complete;
 	struct resource		*ioarea;
 	u32			latency;	/* maximum mpu wkup latency */
@@ -265,45 +264,18 @@ static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *i2c_dev, int reg)
 				(i2c_dev->regs[reg] << i2c_dev->reg_shift));
 }
 
-static int __init omap_i2c_get_clocks(struct omap_i2c_dev *dev)
+static void omap_i2c_unidle(struct omap_i2c_dev *dev)
 {
-	int ret;
+	struct platform_device *pdev;
+	struct omap_i2c_bus_platform_data *pdata;
 
-	dev->iclk = clk_get(dev->dev, "ick");
-	if (IS_ERR(dev->iclk)) {
-		ret = PTR_ERR(dev->iclk);
-		dev->iclk = NULL;
-		return ret;
-	}
+	WARN_ON(!dev->idle);
 
-	dev->fclk = clk_get(dev->dev, "fck");
-	if (IS_ERR(dev->fclk)) {
-		ret = PTR_ERR(dev->fclk);
-		if (dev->iclk != NULL) {
-			clk_put(dev->iclk);
-			dev->iclk = NULL;
-		}
-		dev->fclk = NULL;
-		return ret;
-	}
+	pdev = to_platform_device(dev->dev);
+	pdata = pdev->dev.platform_data;
 
-	return 0;
-}
+	pm_runtime_get_sync(&pdev->dev);
 
-static void omap_i2c_put_clocks(struct omap_i2c_dev *dev)
-{
-	clk_put(dev->fclk);
-	dev->fclk = NULL;
-	clk_put(dev->iclk);
-	dev->iclk = NULL;
-}
-
-static void omap_i2c_unidle(struct omap_i2c_dev *dev)
-{
-	WARN_ON(!dev->idle);
-
-	clk_enable(dev->iclk);
-	clk_enable(dev->fclk);
 	if (cpu_is_omap34xx()) {
 		omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
 		omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, dev->pscstate);
@@ -326,10 +298,15 @@ static void omap_i2c_unidle(struct omap_i2c_dev *dev)
 
 static void omap_i2c_idle(struct omap_i2c_dev *dev)
 {
+	struct platform_device *pdev;
+	struct omap_i2c_bus_platform_data *pdata;
 	u16 iv;
 
 	WARN_ON(dev->idle);
 
+	pdev = to_platform_device(dev->dev);
+	pdata = pdev->dev.platform_data;
+
 	dev->iestate = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
 	if (dev->rev >= OMAP_I2C_REV_ON_4430)
 		omap_i2c_write_reg(dev, OMAP_I2C_IRQENABLE_CLR, 1);
@@ -345,8 +322,8 @@ static void omap_i2c_idle(struct omap_i2c_dev *dev)
 		omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
 	}
 	dev->idle = 1;
-	clk_disable(dev->fclk);
-	clk_disable(dev->iclk);
+
+	pm_runtime_put_sync(&pdev->dev);
 }
 
 static int omap_i2c_init(struct omap_i2c_dev *dev)
@@ -356,6 +333,7 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
 	unsigned long fclk_rate = 12000000;
 	unsigned long timeout;
 	unsigned long internal_clk = 0;
+	struct clk *fclk;
 
 	if (dev->rev >= OMAP_I2C_REV_2) {
 		/* Disable I2C controller before soft reset */
@@ -414,7 +392,8 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
 		 * always returns 12MHz for the functional clock, we can
 		 * do this bit unconditionally.
 		 */
-		fclk_rate = clk_get_rate(dev->fclk);
+		fclk = clk_get(dev->dev, "fck");
+		fclk_rate = clk_get_rate(fclk);
 
 		/* TRM for 5912 says the I2C clock must be prescaled to be
 		 * between 7 - 12 MHz. The XOR input clock is typically
@@ -443,7 +422,8 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
 			internal_clk = 9600;
 		else
 			internal_clk = 4000;
-		fclk_rate = clk_get_rate(dev->fclk) / 1000;
+		fclk = clk_get(dev->dev, "fck");
+		fclk_rate = clk_get_rate(fclk) / 1000;
 
 		/* Compute prescaler divisor */
 		psc = fclk_rate / internal_clk;
@@ -1046,14 +1026,12 @@ omap_i2c_probe(struct platform_device *pdev)
 	else
 		dev->reg_shift = 2;
 
-	if ((r = omap_i2c_get_clocks(dev)) != 0)
-		goto err_iounmap;
-
 	if (cpu_is_omap44xx())
 		dev->regs = (u8 *) omap4_reg_map;
 	else
 		dev->regs = (u8 *) reg_map;
 
+	pm_runtime_enable(&pdev->dev);
 	omap_i2c_unidle(dev);
 
 	dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) & 0xff;
@@ -1125,8 +1103,6 @@ err_free_irq:
 err_unuse_clocks:
 	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
 	omap_i2c_idle(dev);
-	omap_i2c_put_clocks(dev);
-err_iounmap:
 	iounmap(dev->base);
 err_free_mem:
 	platform_set_drvdata(pdev, NULL);
@@ -1148,7 +1124,6 @@ omap_i2c_remove(struct platform_device *pdev)
 	free_irq(dev->irq, dev);
 	i2c_del_adapter(&dev->adapter);
 	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
-	omap_i2c_put_clocks(dev);
 	iounmap(dev->base);
 	kfree(dev);
 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-- 
1.5.4.7




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