OMAP: DSS2: Taal: Add panel hardware reset

Issue a proper reset pulse on the reset line instead of just doing power
on/off.

Signed-off-by: Jani Nikula <ext-jani.1.nikula@nokia.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@nokia.com>

1 files changed, 40 insertions, 4 deletions

diff --git a/drivers/video/omap2/displays/panel-taal.c b/drivers/video/omap2/displays/panel-taal.c
index d2e2ac7444e0..8fbb94e2bf5d 100644
--- a/drivers/video/omap2/displays/panel-taal.c
+++ b/drivers/video/omap2/displays/panel-taal.c
@@ -490,6 +490,22 @@ static struct attribute_group taal_attr_group = {
         .attrs = taal_attrs,
 };
 
+static void taal_hw_reset(struct omap_dss_device *dssdev)
+{
+        if (dssdev->reset_gpio == -1)
+                return;
+
+        gpio_set_value(dssdev->reset_gpio, 1);
+        udelay(10);
+        /* reset the panel */
+        gpio_set_value(dssdev->reset_gpio, 0);
+        /* assert reset for at least 10us */
+        udelay(10);
+        gpio_set_value(dssdev->reset_gpio, 1);
+        /* wait 5ms after releasing reset */
+        msleep(5);
+}
+
 static int taal_probe(struct omap_dss_device *dssdev)
 {
         struct backlight_properties props;
@@ -527,6 +543,8 @@ static int taal_probe(struct omap_dss_device *dssdev)
 
         dev_set_drvdata(&dssdev->dev, td);
 
+        taal_hw_reset(dssdev);
+
         /* if no platform set_backlight() defined, presume DSI backlight
          * control */
         memset(&props, 0, sizeof(struct backlight_properties));
@@ -628,6 +646,9 @@ static void taal_remove(struct omap_dss_device *dssdev)
         cancel_delayed_work_sync(&td->esd_work);
         destroy_workqueue(td->esd_wq);
 
+        /* reset, to be sure that the panel is in a valid state */
+        taal_hw_reset(dssdev);
+
         kfree(td);
 }
 
@@ -654,6 +675,8 @@ static int taal_power_on(struct omap_dss_device *dssdev)
                 goto err0;
         }
 
+        taal_hw_reset(dssdev);
+
         omapdss_dsi_vc_enable_hs(TCH, false);
 
         r = taal_sleep_out(td);
@@ -704,6 +727,10 @@ static int taal_power_on(struct omap_dss_device *dssdev)
 
         return 0;
 err:
+        dev_err(&dssdev->dev, "error while enabling panel, issuing HW reset\n");
+
+        taal_hw_reset(dssdev);
+
         omapdss_dsi_display_disable(dssdev);
 err0:
         dsi_bus_unlock();
@@ -716,16 +743,24 @@ err0:
 static void taal_power_off(struct omap_dss_device *dssdev)
 {
         struct taal_data *td = dev_get_drvdata(&dssdev->dev);
+        int r;
 
         dsi_bus_lock();
 
         cancel_delayed_work(&td->esd_work);
 
-        taal_dcs_write_0(DCS_DISPLAY_OFF);
-        taal_sleep_in(td);
+        r = taal_dcs_write_0(DCS_DISPLAY_OFF);
+        if (!r) {
+                r = taal_sleep_in(td);
+                /* wait a bit so that the message goes through */
+                msleep(10);
+        }
 
-        /* wait a bit so that the message goes through */
-        msleep(10);
+        if (r) {
+                dev_err(&dssdev->dev,
+                                "error disabling panel, issuing HW reset\n");
+                taal_hw_reset(dssdev);
+        }
 
         omapdss_dsi_display_disable(dssdev);
 
@@ -1186,6 +1221,7 @@ err:
         dev_err(&dssdev->dev, "performing LCD reset\n");
 
         taal_power_off(dssdev);
+        taal_hw_reset(dssdev);
         taal_power_on(dssdev);
 
         dsi_bus_unlock();