video: fbdev: pxafb: Add support for lcd-supply regulator
Optionally obtain a lcd-supply regulator during probe and use it in
__pxafb_lcd_power() to switch the power supply of LCD panels.
This helps boards booted from DT to control such voltages without
callbacks.
Signed-off-by: Daniel Mack <daniel@zonque.org>
Reviewed-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
diff --git a/Documentation/devicetree/bindings/display/marvell,pxa2xx-lcdc.txt b/Documentation/devicetree/bindings/display/marvell,pxa2xx-lcdc.txt
index f79641b..45ffd6c 100644
--- a/Documentation/devicetree/bindings/display/marvell,pxa2xx-lcdc.txt
+++ b/Documentation/devicetree/bindings/display/marvell,pxa2xx-lcdc.txt
@@ -10,6 +10,9 @@
- interrupts : framebuffer controller interrupt.
- clocks: phandle to input clocks
+Optional properties:
+ - lcd-supply: A phandle to a power regulator that controls the LCD voltage.
+
Required nodes:
- port: connection to the LCD panel (see video-interfaces.txt)
This node must have its properties bus-width and remote-endpoint set.
diff --git a/drivers/video/fbdev/pxafb.c b/drivers/video/fbdev/pxafb.c
index 68459b0..bbed039 100644
--- a/drivers/video/fbdev/pxafb.c
+++ b/drivers/video/fbdev/pxafb.c
@@ -56,6 +56,7 @@
#include <linux/freezer.h>
#include <linux/console.h>
#include <linux/of_graph.h>
+#include <linux/regulator/consumer.h>
#include <video/of_display_timing.h>
#include <video/videomode.h>
@@ -1423,6 +1424,21 @@ static inline void __pxafb_lcd_power(struct pxafb_info *fbi, int on)
if (fbi->lcd_power)
fbi->lcd_power(on, &fbi->fb.var);
+
+ if (fbi->lcd_supply && fbi->lcd_supply_enabled != on) {
+ int ret;
+
+ if (on)
+ ret = regulator_enable(fbi->lcd_supply);
+ else
+ ret = regulator_disable(fbi->lcd_supply);
+
+ if (ret < 0)
+ pr_warn("Unable to %s LCD supply regulator: %d\n",
+ on ? "enable" : "disable", ret);
+ else
+ fbi->lcd_supply_enabled = on;
+ }
}
static void pxafb_enable_controller(struct pxafb_info *fbi)
@@ -2299,6 +2315,14 @@ static int pxafb_probe(struct platform_device *dev)
fbi->backlight_power = inf->pxafb_backlight_power;
fbi->lcd_power = inf->pxafb_lcd_power;
+ fbi->lcd_supply = devm_regulator_get_optional(&dev->dev, "lcd");
+ if (IS_ERR(fbi->lcd_supply)) {
+ if (PTR_ERR(fbi->lcd_supply) == -EPROBE_DEFER)
+ return -EPROBE_DEFER;
+
+ fbi->lcd_supply = NULL;
+ }
+
r = platform_get_resource(dev, IORESOURCE_MEM, 0);
if (r == NULL) {
dev_err(&dev->dev, "no I/O memory resource defined\n");
diff --git a/drivers/video/fbdev/pxafb.h b/drivers/video/fbdev/pxafb.h
index 5dc414e..b641289 100644
--- a/drivers/video/fbdev/pxafb.h
+++ b/drivers/video/fbdev/pxafb.h
@@ -165,6 +165,9 @@ struct pxafb_info {
struct notifier_block freq_policy;
#endif
+ struct regulator *lcd_supply;
+ bool lcd_supply_enabled;
+
void (*lcd_power)(int, struct fb_var_screeninfo *);
void (*backlight_power)(int);
