i2c-ocores: basic PM support

Basic PM support: reinit the core on resume, disable it on suspend.

Signed-off-by: Manuel Lauss <mano@roarinelk.homelinux.net>
Acked-by: Peter Korsgaard <jacmet@sunsite.dk>
Signed-off-by: Jean Delvare <khali@linux-fr.org>

1 files changed, 35 insertions, 7 deletions

diff --git a/drivers/i2c/busses/i2c-ocores.c b/drivers/i2c/busses/i2c-ocores.c
index 51ca79bf6480..e5193bf75483 100644
--- a/drivers/i2c/busses/i2c-ocores.c
+++ b/drivers/i2c/busses/i2c-ocores.c
@@ -29,6 +29,7 @@ struct ocores_i2c {
         int pos;
         int nmsgs;
         int state; /* see STATE_ */
+        int clock_khz;
 };
 
 /* registers */
@@ -173,8 +174,7 @@ static int ocores_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
                 return -ETIMEDOUT;
 }
 
-static void ocores_init(struct ocores_i2c *i2c,
-                        struct ocores_i2c_platform_data *pdata)
+static void ocores_init(struct ocores_i2c *i2c)
 {
         int prescale;
         u8 ctrl = oc_getreg(i2c, OCI2C_CONTROL);
@@ -182,7 +182,7 @@ static void ocores_init(struct ocores_i2c *i2c,
         /* make sure the device is disabled */
         oc_setreg(i2c, OCI2C_CONTROL, ctrl & ~(OCI2C_CTRL_EN|OCI2C_CTRL_IEN));
 
-        prescale = (pdata->clock_khz / (5*100)) - 1;
+        prescale = (i2c->clock_khz / (5*100)) - 1;
         oc_setreg(i2c, OCI2C_PRELOW, prescale & 0xff);
         oc_setreg(i2c, OCI2C_PREHIGH, prescale >> 8);
 
@@ -248,7 +248,8 @@ static int __devinit ocores_i2c_probe(struct platform_device *pdev)
         }
 
         i2c->regstep = pdata->regstep;
-        ocores_init(i2c, pdata);
+        i2c->clock_khz = pdata->clock_khz;
+        ocores_init(i2c);
 
         init_waitqueue_head(&i2c->wait);
         ret = request_irq(res2->start, ocores_isr, 0, pdev->name, i2c);
@@ -312,13 +313,40 @@ static int __devexit ocores_i2c_remove(struct platform_device* pdev)
         return 0;
 }
 
+#ifdef CONFIG_PM
+static int ocores_i2c_suspend(struct platform_device *pdev, pm_message_t state)
+{
+        struct ocores_i2c *i2c = platform_get_drvdata(pdev);
+        u8 ctrl = oc_getreg(i2c, OCI2C_CONTROL);
+
+        /* make sure the device is disabled */
+        oc_setreg(i2c, OCI2C_CONTROL, ctrl & ~(OCI2C_CTRL_EN|OCI2C_CTRL_IEN));
+
+        return 0;
+}
+
+static int ocores_i2c_resume(struct platform_device *pdev)
+{
+        struct ocores_i2c *i2c = platform_get_drvdata(pdev);
+
+        ocores_init(i2c);
+
+        return 0;
+}
+#else
+#define ocores_i2c_suspend      NULL
+#define ocores_i2c_resume       NULL
+#endif
+
 /* work with hotplug and coldplug */
 MODULE_ALIAS("platform:ocores-i2c");
 
 static struct platform_driver ocores_i2c_driver = {
-        .probe  = ocores_i2c_probe,
-        .remove = __devexit_p(ocores_i2c_remove),
-        .driver = {
+        .probe   = ocores_i2c_probe,
+        .remove  = __devexit_p(ocores_i2c_remove),
+        .suspend = ocores_i2c_suspend,
+        .resume  = ocores_i2c_resume,
+        .driver  = {
                 .owner = THIS_MODULE,
                 .name = "ocores-i2c",
         },