OMAP: DSS2: Taal: Add regulator configuration support

Add support for configuring regulators in the panel specific
configuration data.

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

1 files changed, 83 insertions, 0 deletions

diff --git a/drivers/video/omap2/displays/panel-taal.c b/drivers/video/omap2/displays/panel-taal.c
index cbe0214e2f05..941f1f208c9e 100644
--- a/drivers/video/omap2/displays/panel-taal.c
+++ b/drivers/video/omap2/displays/panel-taal.c
@@ -30,6 +30,7 @@
 #include <linux/gpio.h>
 #include <linux/workqueue.h>
 #include <linux/slab.h>
+#include <linux/regulator/consumer.h>
 #include <linux/mutex.h>
 
 #include <plat/display.h>
@@ -68,6 +69,73 @@ static irqreturn_t taal_te_isr(int irq, void *data);
 static void taal_te_timeout_work_callback(struct work_struct *work);
 static int _taal_enable_te(struct omap_dss_device *dssdev, bool enable);
 
+struct panel_regulator {
+        struct regulator *regulator;
+        const char *name;
+        int min_uV;
+        int max_uV;
+};
+
+static void free_regulators(struct panel_regulator *regulators, int n)
+{
+        int i;
+
+        for (i = 0; i < n; i++) {
+                /* disable/put in reverse order */
+                regulator_disable(regulators[n - i - 1].regulator);
+                regulator_put(regulators[n - i - 1].regulator);
+        }
+}
+
+static int init_regulators(struct omap_dss_device *dssdev,
+                        struct panel_regulator *regulators, int n)
+{
+        int r, i, v;
+
+        for (i = 0; i < n; i++) {
+                struct regulator *reg;
+
+                reg = regulator_get(&dssdev->dev, regulators[i].name);
+                if (IS_ERR(reg)) {
+                        dev_err(&dssdev->dev, "failed to get regulator %s\n",
+                                regulators[i].name);
+                        r = PTR_ERR(reg);
+                        goto err;
+                }
+
+                /* FIXME: better handling of fixed vs. variable regulators */
+                v = regulator_get_voltage(reg);
+                if (v < regulators[i].min_uV || v > regulators[i].max_uV) {
+                        r = regulator_set_voltage(reg, regulators[i].min_uV,
+                                                regulators[i].max_uV);
+                        if (r) {
+                                dev_err(&dssdev->dev,
+                                        "failed to set regulator %s voltage\n",
+                                        regulators[i].name);
+                                regulator_put(reg);
+                                goto err;
+                        }
+                }
+
+                r = regulator_enable(reg);
+                if (r) {
+                        dev_err(&dssdev->dev, "failed to enable regulator %s\n",
+                                regulators[i].name);
+                        regulator_put(reg);
+                        goto err;
+                }
+
+                regulators[i].regulator = reg;
+        }
+
+        return 0;
+
+err:
+        free_regulators(regulators, i);
+
+        return r;
+}
+
 /**
  * struct panel_config - panel configuration
  * @name: panel name
@@ -75,6 +143,8 @@ static int _taal_enable_te(struct omap_dss_device *dssdev, bool enable);
  * @timings: panel resolution
  * @sleep: various panel specific delays, passed to msleep() if non-zero
  * @reset_sequence: reset sequence timings, passed to udelay() if non-zero
+ * @regulators: array of panel regulators
+ * @num_regulators: number of regulators in the array
  */
 struct panel_config {
         const char *name;
@@ -93,6 +163,9 @@ struct panel_config {
                 unsigned int high;
                 unsigned int low;
         } reset_sequence;
+
+        struct panel_regulator *regulators;
+        int num_regulators;
 };
 
 enum {
@@ -629,6 +702,11 @@ static int taal_probe(struct omap_dss_device *dssdev)
 
         atomic_set(&td->do_update, 0);
 
+        r = init_regulators(dssdev, panel_config->regulators,
+                        panel_config->num_regulators);
+        if (r)
+                goto err_reg;
+
         td->esd_wq = create_singlethread_workqueue("taal_esd");
         if (td->esd_wq == NULL) {
                 dev_err(&dssdev->dev, "can't create ESD workqueue\n");
@@ -714,6 +792,8 @@ err_gpio:
 err_bl:
         destroy_workqueue(td->esd_wq);
 err_wq:
+        free_regulators(panel_config->regulators, panel_config->num_regulators);
+err_reg:
         kfree(td);
 err:
         return r;
@@ -746,6 +826,9 @@ static void taal_remove(struct omap_dss_device *dssdev)
         /* reset, to be sure that the panel is in a valid state */
         taal_hw_reset(dssdev);
 
+        free_regulators(td->panel_config->regulators,
+                        td->panel_config->num_regulators);
+
         kfree(td);
 }