fbdev/ssd1307fb: add support to enable VBAT

SSD1306 needs VBAT when it is wired in charge pump configuration. This
patch adds support to the driver to enable VBAT regulator at init time.

Cc: Rob Herring <robh+dt@kernel.org>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Benoît Cousson <bcousson@baylibre.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Reviewed-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Jyri Sarha <jsarha@ti.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

diff --git a/Documentation/devicetree/bindings/display/ssd1307fb.txt b/Documentation/devicetree/bindings/display/ssd1307fb.txt
index 6617df68d8b8675dcfad49221e6a2717db94be50..209d931ef16c4e53e46e8378b09f5cf04b121586 100644 (file)
--- a/Documentation/devicetree/bindings/display/ssd1307fb.txt
+++ b/Documentation/devicetree/bindings/display/ssd1307fb.txt
@@ -16,6 +16,7 @@ Required properties:
 Optional properties:
   - reset-gpios: The GPIO used to reset the OLED display, if available. See
                  Documentation/devicetree/bindings/gpio/gpio.txt for details.
+  - vbat-supply: The supply for VBAT
   - solomon,segment-no-remap: Display needs normal (non-inverted) data column
                               to segment mapping
   - solomon,com-seq: Display uses sequential COM pin configuration

diff --git a/drivers/video/fbdev/ssd1307fb.c b/drivers/video/fbdev/ssd1307fb.c
index 89372af7bc5b508bdbb3333b7953a4903cc8c00d..616a6a3fabf978d958a31e8a91e57e57141be591 100644 (file)
--- a/drivers/video/fbdev/ssd1307fb.c
+++ b/drivers/video/fbdev/ssd1307fb.c
@@ -16,6 +16,7 @@
 #include <linux/of_gpio.h>
 #include <linux/pwm.h>
 #include <linux/uaccess.h>
+#include <linux/regulator/consumer.h>
 
 #define SSD1307FB_DATA                 0x40
 #define SSD1307FB_COMMAND              0x80
@@ -74,6 +75,7 @@ struct ssd1307fb_par {
        struct pwm_device *pwm;
        u32 pwm_period;
        struct gpio_desc *reset;
+       struct regulator *vbat_reg;
        u32 seg_remap;
        u32 vcomh;
        u32 width;
@@ -574,6 +576,14 @@ static int ssd1307fb_probe(struct i2c_client *client,
                goto fb_alloc_error;
        }
 
+       par->vbat_reg = devm_regulator_get_optional(&client->dev, "vbat");
+       if (IS_ERR(par->vbat_reg)) {
+               dev_err(&client->dev, "failed to get VBAT regulator: %ld\n",
+                       PTR_ERR(par->vbat_reg));
+               ret = PTR_ERR(par->vbat_reg);
+               goto fb_alloc_error;
+       }
+
        if (of_property_read_u32(node, "solomon,width", &par->width))
                par->width = 96;
 
@@ -658,9 +668,15 @@ static int ssd1307fb_probe(struct i2c_client *client,
                udelay(4);
        }
 
+       ret = regulator_enable(par->vbat_reg);
+       if (ret) {
+               dev_err(&client->dev, "failed to enable VBAT: %d\n", ret);
+               goto reset_oled_error;
+       }
+
        ret = ssd1307fb_init(par);
        if (ret)
-               goto reset_oled_error;
+               goto regulator_enable_error;
 
        ret = register_framebuffer(info);
        if (ret) {
@@ -693,6 +709,8 @@ panel_init_error:
                pwm_disable(par->pwm);
                pwm_put(par->pwm);
        };
+regulator_enable_error:
+       regulator_disable(par->vbat_reg);
 reset_oled_error:
        fb_deferred_io_cleanup(info);
 fb_alloc_error: