drivers/video/backlight/l4f00242t03.c: full implement fb power states for this lcd

Complete the support of fb power states managing correctly the regulators
bound to this driver.

Signed-off-by: Alberto Panizzo <maramaopercheseimorto@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Marek Vasut <marek.vasut@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/video/backlight/l4f00242t03.c b/drivers/video/backlight/l4f00242t03.c
index 6d9ba0e2b0c50e2429dcb61c90eb611e6af115e5..5d25743bf8e26001d00b2cbd558dd67f7b07468b 100644 (file)
--- a/drivers/video/backlight/l4f00242t03.c
+++ b/drivers/video/backlight/l4f00242t03.c
@@ -25,7 +25,7 @@
 struct l4f00242t03_priv {
        struct spi_device       *spi;
        struct lcd_device       *ld;
-       unsigned int lcd_on:1;
+       int lcd_state;
        struct regulator *io_reg;
        struct regulator *core_reg;
 };
@@ -67,6 +67,29 @@ static void l4f00242t03_lcd_init(struct spi_device *spi)
        spi_write(spi, (const u8 *)cmd, ARRAY_SIZE(cmd) * sizeof(u16));
 }
 
+static void l4f00242t03_lcd_powerdown(struct spi_device *spi)
+{
+       struct l4f00242t03_pdata *pdata = spi->dev.platform_data;
+       struct l4f00242t03_priv *priv = dev_get_drvdata(&spi->dev);
+
+       dev_dbg(&spi->dev, "Powering down LCD\n");
+
+       gpio_set_value(pdata->data_enable_gpio, 0);
+
+       if (priv->io_reg)
+               regulator_disable(priv->io_reg);
+
+       if (priv->core_reg)
+               regulator_disable(priv->core_reg);
+}
+
+static int l4f00242t03_lcd_power_get(struct lcd_device *ld)
+{
+       struct l4f00242t03_priv *priv = lcd_get_data(ld);
+
+       return priv->lcd_state;
+}
+
 static int l4f00242t03_lcd_power_set(struct lcd_device *ld, int power)
 {
        struct l4f00242t03_priv *priv = lcd_get_data(ld);
@@ -79,35 +102,52 @@ static int l4f00242t03_lcd_power_set(struct lcd_device *ld, int power)
        const u16 disoff = 0x28;
 
        if (power <= FB_BLANK_NORMAL) {
-               if (priv->lcd_on)
-                       return 0;
-
-               dev_dbg(&spi->dev, "turning on LCD\n");
-
-               spi_write(spi, (const u8 *)&slpout, sizeof(u16));
-               msleep(60);
-               spi_write(spi, (const u8 *)&dison, sizeof(u16));
-
-               priv->lcd_on = 1;
+               if (priv->lcd_state <= FB_BLANK_NORMAL) {
+                       /* Do nothing, the LCD is running */
+               } else if (priv->lcd_state < FB_BLANK_POWERDOWN) {
+                       dev_dbg(&spi->dev, "Resuming LCD\n");
+
+                       spi_write(spi, (const u8 *)&slpout, sizeof(u16));
+                       msleep(60);
+                       spi_write(spi, (const u8 *)&dison, sizeof(u16));
+               } else {
+                       /* priv->lcd_state == FB_BLANK_POWERDOWN */
+                       l4f00242t03_lcd_init(spi);
+                       priv->lcd_state = FB_BLANK_VSYNC_SUSPEND;
+                       l4f00242t03_lcd_power_set(priv->ld, power);
+               }
+       } else if (power < FB_BLANK_POWERDOWN) {
+               if (priv->lcd_state <= FB_BLANK_NORMAL) {
+                       /* Send the display in standby */
+                       dev_dbg(&spi->dev, "Standby the LCD\n");
+
+                       spi_write(spi, (const u8 *)&disoff, sizeof(u16));
+                       msleep(60);
+                       spi_write(spi, (const u8 *)&slpin, sizeof(u16));
+               } else if (priv->lcd_state < FB_BLANK_POWERDOWN) {
+                       /* Do nothing, the LCD is already in standby */
+               } else {
+                       /* priv->lcd_state == FB_BLANK_POWERDOWN */
+                       l4f00242t03_lcd_init(spi);
+                       priv->lcd_state = FB_BLANK_UNBLANK;
+                       l4f00242t03_lcd_power_set(ld, power);
+               }
        } else {
-               if (!priv->lcd_on)
-                       return 0;
-
-               dev_dbg(&spi->dev, "turning off LCD\n");
-
+               /* power == FB_BLANK_POWERDOWN */
+               /* Clear the screen before shutting down */
                spi_write(spi, (const u8 *)&disoff, sizeof(u16));
                msleep(60);
-               spi_write(spi, (const u8 *)&slpin, sizeof(u16));
-
-               priv->lcd_on = 0;
+               l4f00242t03_lcd_powerdown(spi);
        }
 
+       priv->lcd_state = power;
+
        return 0;
 }
 
 static struct lcd_ops l4f_ops = {
        .set_power      = l4f00242t03_lcd_power_set,
-       .get_power      = NULL,
+       .get_power      = l4f00242t03_lcd_power_get,
 };
 
 static int __devinit l4f00242t03_probe(struct spi_device *spi)
@@ -187,7 +227,8 @@ static int __devinit l4f00242t03_probe(struct spi_device *spi)
        /* Init the LCD */
        l4f00242t03_reset(pdata->reset_gpio);
        l4f00242t03_lcd_init(spi);
-       l4f00242t03_lcd_power_set(priv->ld, 1);
+       priv->lcd_state = FB_BLANK_VSYNC_SUSPEND;
+       l4f00242t03_lcd_power_set(priv->ld, FB_BLANK_UNBLANK);
 
        dev_info(&spi->dev, "Epson l4f00242t03 lcd probed.\n");
 
@@ -214,9 +255,11 @@ static int __devexit l4f00242t03_remove(struct spi_device *spi)
        struct l4f00242t03_priv *priv = dev_get_drvdata(&spi->dev);
        struct l4f00242t03_pdata *pdata = priv->spi->dev.platform_data;
 
-       l4f00242t03_lcd_power_set(priv->ld, 0);
+       l4f00242t03_lcd_power_set(priv->ld, FB_BLANK_POWERDOWN);
        lcd_device_unregister(priv->ld);
 
+       dev_set_drvdata(&spi->dev, NULL);
+
        gpio_free(pdata->data_enable_gpio);
        gpio_free(pdata->reset_gpio);
 
@@ -230,6 +273,15 @@ static int __devexit l4f00242t03_remove(struct spi_device *spi)
        return 0;
 }
 
+static void l4f00242t03_shutdown(struct spi_device *spi)
+{
+       struct l4f00242t03_priv *priv = dev_get_drvdata(&spi->dev);
+
+       if (priv)
+               l4f00242t03_lcd_power_set(priv->ld, FB_BLANK_POWERDOWN);
+
+}
+
 static struct spi_driver l4f00242t03_driver = {
        .driver = {
                .name   = "l4f00242t03",
@@ -237,6 +289,7 @@ static struct spi_driver l4f00242t03_driver = {
        },
        .probe          = l4f00242t03_probe,
        .remove         = __devexit_p(l4f00242t03_remove),
+       .shutdown       = l4f00242t03_shutdown,
 };
 
 static __init int l4f00242t03_init(void)