viafb: suspend/resume for GPIOs

Be sure to re-enable GPIO lines on resume.  Users still have to
be sure to set them properly.

Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Daniel Drake <dsd@laptop.org>
Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>

1 files changed, 29 insertions, 0 deletions

diff --git a/drivers/video/via/via-gpio.c b/drivers/video/via/via-gpio.c
index 39acb37e7a1d..c2a0a1cfd3b3 100644
--- a/drivers/video/via/via-gpio.c
+++ b/drivers/video/via/via-gpio.c
@@ -172,6 +172,28 @@ static void viafb_gpio_disable(struct viafb_gpio *gpio)
         via_write_reg_mask(VIASR, gpio->vg_port_index, 0, 0x02);
 }
 
+#ifdef CONFIG_PM
+
+static int viafb_gpio_suspend(void *private)
+{
+        return 0;
+}
+
+static int viafb_gpio_resume(void *private)
+{
+        int i;
+
+        for (i = 0; i < gpio_config.gpio_chip.ngpio; i += 2)
+                viafb_gpio_enable(gpio_config.active_gpios[i]);
+        return 0;
+}
+
+static struct viafb_pm_hooks viafb_gpio_pm_hooks = {
+        .suspend = viafb_gpio_suspend,
+        .resume = viafb_gpio_resume
+};
+#endif /* CONFIG_PM */
+
 /*
  * Look up a specific gpio and return the number it was assigned.
  */
@@ -236,6 +258,9 @@ static __devinit int viafb_gpio_probe(struct platform_device *platdev)
                 printk(KERN_ERR "viafb: failed to add gpios (%d)\n", ret);
                 gpio_config.gpio_chip.ngpio = 0;
         }
+#ifdef CONFIG_PM
+        viafb_pm_register(&viafb_gpio_pm_hooks);
+#endif
         return ret;
 }
 
@@ -245,6 +270,10 @@ static int viafb_gpio_remove(struct platform_device *platdev)
         unsigned long flags;
         int ret = 0, i;
 
+#ifdef CONFIG_PM
+        viafb_pm_unregister(&viafb_gpio_pm_hooks);
+#endif
+
         /*
          * Get unregistered.
          */