Merge branch 'for-33' of git://repo.or.cz/linux-kbuild

[linux-2.6-block.git] / drivers / i2c / busses / i2c-sh_mobile.c

diff --git a/drivers/i2c/busses/i2c-sh_mobile.c b/drivers/i2c/busses/i2c-sh_mobile.c
index 820487d0d5c72eb13e301991d7008dec2bba75f5..ccc46418ef7f16b2409c28cdf7f7f8ebdb6796d4 100644 (file)
--- a/drivers/i2c/busses/i2c-sh_mobile.c
+++ b/drivers/i2c/busses/i2c-sh_mobile.c
@@ -28,6 +28,7 @@
 #include <linux/interrupt.h>
 #include <linux/i2c.h>
 #include <linux/err.h>
+#include <linux/pm_runtime.h>
 #include <linux/clk.h>
 #include <linux/io.h>
 
@@ -165,7 +166,8 @@ static void activate_ch(struct sh_mobile_i2c_data *pd)
        u_int32_t denom;
        u_int32_t tmp;
 
-       /* Make sure the clock is enabled */
+       /* Wake up device and enable clock */
+       pm_runtime_get_sync(pd->dev);
        clk_enable(pd->clk);
 
        /* Get clock rate after clock is enabled */
@@ -213,8 +215,9 @@ static void deactivate_ch(struct sh_mobile_i2c_data *pd)
        /* Disable channel */
        iowrite8(ioread8(ICCR(pd)) & ~ICCR_ICE, ICCR(pd));
 
-       /* Disable clock */
+       /* Disable clock and mark device as idle */
        clk_disable(pd->clk);
+       pm_runtime_put_sync(pd->dev);
 }
 
 static unsigned char i2c_op(struct sh_mobile_i2c_data *pd,
@@ -572,6 +575,19 @@ static int sh_mobile_i2c_probe(struct platform_device *dev)
                goto err_irq;
        }
 
+       /* Enable Runtime PM for this device.
+        *
+        * Also tell the Runtime PM core to ignore children
+        * for this device since it is valid for us to suspend
+        * this I2C master driver even though the slave devices
+        * on the I2C bus may not be suspended.
+        *
+        * The state of the I2C hardware bus is unaffected by
+        * the Runtime PM state.
+        */
+       pm_suspend_ignore_children(&dev->dev, true);
+       pm_runtime_enable(&dev->dev);
+
        /* setup the private data */
        adap = &pd->adap;
        i2c_set_adapdata(adap, pd);
@@ -614,14 +630,33 @@ static int sh_mobile_i2c_remove(struct platform_device *dev)
        iounmap(pd->reg);
        sh_mobile_i2c_hook_irqs(dev, 0);
        clk_put(pd->clk);
+       pm_runtime_disable(&dev->dev);
        kfree(pd);
        return 0;
 }
 
+static int sh_mobile_i2c_runtime_nop(struct device *dev)
+{
+       /* Runtime PM callback shared between ->runtime_suspend()
+        * and ->runtime_resume(). Simply returns success.
+        *
+        * This driver re-initializes all registers after
+        * pm_runtime_get_sync() anyway so there is no need
+        * to save and restore registers here.
+        */
+       return 0;
+}
+
+static const struct dev_pm_ops sh_mobile_i2c_dev_pm_ops = {
+       .runtime_suspend = sh_mobile_i2c_runtime_nop,
+       .runtime_resume = sh_mobile_i2c_runtime_nop,
+};
+
 static struct platform_driver sh_mobile_i2c_driver = {
        .driver         = {
                .name           = "i2c-sh_mobile",
                .owner          = THIS_MODULE,
+               .pm             = &sh_mobile_i2c_dev_pm_ops,
        },
        .probe          = sh_mobile_i2c_probe,
        .remove         = sh_mobile_i2c_remove,