abituguru: Add suspend/resume support

This patch contains rudimentary suspend / resume support for the uguru,
this protects the uguru and the driver against suspend / resume cycles,
so there is no reason to unload the driver in your suspend / resume
scripts.

Only include suspend / resume functions when CONFIG_PM is set.

Signed-off-by: Hans de Goede <j.w.r.degoede@hhs.nl>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 28 insertions, 2 deletions

diff --git a/drivers/hwmon/abituguru.c b/drivers/hwmon/abituguru.c
index 35ad1b032726..e5cb0fdab9b1 100644
--- a/drivers/hwmon/abituguru.c
+++ b/drivers/hwmon/abituguru.c
@@ -1354,13 +1354,39 @@ LEAVE_UPDATE:
                 return NULL;
 }
 
+#ifdef CONFIG_PM
+static int abituguru_suspend(struct platform_device *pdev, pm_message_t state)
+{
+        struct abituguru_data *data = platform_get_drvdata(pdev);
+        /* make sure all communications with the uguru are done and no new
+           ones are started */
+        mutex_lock(&data->update_lock);
+        return 0;
+}
+
+static int abituguru_resume(struct platform_device *pdev)
+{
+        struct abituguru_data *data = platform_get_drvdata(pdev);
+        /* See if the uGuru is still ready */
+        if (inb_p(data->addr + ABIT_UGURU_DATA) != ABIT_UGURU_STATUS_INPUT)
+                data->uguru_ready = 0;
+        mutex_unlock(&data->update_lock);
+        return 0;
+}
+#else
+#define abituguru_suspend       NULL
+#define abituguru_resume        NULL
+#endif /* CONFIG_PM */
+
 static struct platform_driver abituguru_driver = {
         .driver = {
                 .owner  = THIS_MODULE,
                 .name   = ABIT_UGURU_NAME,
         },
-        .probe  = abituguru_probe,
-        .remove = __devexit_p(abituguru_remove),
+        .probe          = abituguru_probe,
+        .remove         = __devexit_p(abituguru_remove),
+        .suspend        = abituguru_suspend,
+        .resume         = abituguru_resume,
 };
 
 static int __init abituguru_detect(void)