backlight: add support for Sharp SL-6000 LCD and backlight drivers

On Sharp SL-6000 lcd/backlight is a bit complex, so add two drivers
one for lcd-driving chip, other one for dac regulating the backlight
LEDS.

Signed-off-by: Dmitry Baryshkov <dbaryshkov@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>

5 files changed, 502 insertions, 0 deletions

diff --git a/arch/arm/mach-pxa/include/mach/tosa.h b/arch/arm/mach-pxa/include/mach/tosa.h
index 8bce6d8615b9..4df2d38507dc 100644
--- a/arch/arm/mach-pxa/include/mach/tosa.h
+++ b/arch/arm/mach-pxa/include/mach/tosa.h
@@ -193,4 +193,7 @@
 #define TOSA_KEY_MAIL           KEY_MAIL
 #endif
 
+struct spi_device;
+extern int tosa_bl_enable(struct spi_device *spi, int enable);
+
 #endif /* _ASM_ARCH_TOSA_H_ */
diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig
index c72a13562954..10b701f1089a 100644
--- a/drivers/video/backlight/Kconfig
+++ b/drivers/video/backlight/Kconfig
@@ -75,6 +75,15 @@ config LCD_PLATFORM
           This driver provides a platform-device registered LCD power
           control interface.
 
+config LCD_TOSA
+        tristate "Sharp SL-6000 LCD Driver"
+        depends on LCD_CLASS_DEVICE && SPI
+        depends on MACH_TOSA
+        default n
+        help
+          If you have an Sharp SL-6000 Zaurus say Y to enable a driver
+          for its LCD.
+
 #
 # Backlight
 #
@@ -179,3 +188,12 @@ config BACKLIGHT_MBP_NVIDIA
          If you have an Apple Macbook Pro with Nvidia graphics hardware say Y
          to enable a driver for its backlight
 
+config BACKLIGHT_TOSA
+        tristate "Sharp SL-6000 Backlight Driver"
+        depends on BACKLIGHT_CLASS_DEVICE && I2C
+        depends on MACH_TOSA && LCD_TOSA
+        default n
+        help
+          If you have an Sharp SL-6000 Zaurus say Y to enable a driver
+          for its backlight
+
diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/Makefile
index 3ec551eb472c..36f2026373a3 100644
--- a/drivers/video/backlight/Makefile
+++ b/drivers/video/backlight/Makefile
@@ -7,6 +7,7 @@ obj-$(CONFIG_LCD_ILI9320)	   += ili9320.o
 obj-$(CONFIG_LCD_PLATFORM)         += platform_lcd.o
 obj-$(CONFIG_LCD_VGG2432A4)        += vgg2432a4.o
 obj-$(CONFIG_LCD_TDO24M)           += tdo24m.o
+obj-$(CONFIG_LCD_TOSA)             += tosa_lcd.o
 
 obj-$(CONFIG_BACKLIGHT_CLASS_DEVICE) += backlight.o
 obj-$(CONFIG_BACKLIGHT_ATMEL_PWM)    += atmel-pwm-bl.o
@@ -18,4 +19,6 @@ obj-$(CONFIG_BACKLIGHT_PROGEAR) += progear_bl.o
 obj-$(CONFIG_BACKLIGHT_CARILLO_RANCH) += cr_bllcd.o
 obj-$(CONFIG_BACKLIGHT_PWM)     += pwm_bl.o
 obj-$(CONFIG_BACKLIGHT_MBP_NVIDIA) += mbp_nvidia_bl.o
+obj-$(CONFIG_BACKLIGHT_TOSA)    += tosa_bl.o
+
 
diff --git a/drivers/video/backlight/tosa_bl.c b/drivers/video/backlight/tosa_bl.c
new file mode 100644
index 000000000000..43edbada12d1
--- /dev/null
+++ b/drivers/video/backlight/tosa_bl.c
@@ -0,0 +1,198 @@
+/*
+ *  LCD / Backlight control code for Sharp SL-6000x (tosa)
+ *
+ *  Copyright (c) 2005          Dirk Opfer
+ *  Copyright (c) 2007,2008     Dmitry Baryshkov
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2 as
+ *  published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/spi/spi.h>
+#include <linux/i2c.h>
+#include <linux/gpio.h>
+#include <linux/fb.h>
+#include <linux/backlight.h>
+
+#include <asm/mach/sharpsl_param.h>
+
+#include <mach/tosa.h>
+
+#define COMADJ_DEFAULT  97
+
+#define DAC_CH1         0
+#define DAC_CH2         1
+
+struct tosa_bl_data {
+        struct i2c_client *i2c;
+        struct backlight_device *bl;
+
+        int comadj;
+};
+
+static void tosa_bl_set_backlight(struct tosa_bl_data *data, int brightness)
+{
+        struct spi_device *spi = data->i2c->dev.platform_data;
+
+        i2c_smbus_write_byte_data(data->i2c, DAC_CH1, data->comadj);
+
+        /* SetBacklightDuty */
+        i2c_smbus_write_byte_data(data->i2c, DAC_CH2, (u8)(brightness & 0xff));
+
+        /* SetBacklightVR */
+        gpio_set_value(TOSA_GPIO_BL_C20MA, brightness & 0x100);
+
+        tosa_bl_enable(spi, brightness);
+}
+
+static int tosa_bl_update_status(struct backlight_device *dev)
+{
+        struct backlight_properties *props = &dev->props;
+        struct tosa_bl_data *data = dev_get_drvdata(&dev->dev);
+        int power = max(props->power, props->fb_blank);
+        int brightness = props->brightness;
+
+        if (power)
+                brightness = 0;
+
+        tosa_bl_set_backlight(data, brightness);
+
+        return 0;
+}
+
+static int tosa_bl_get_brightness(struct backlight_device *dev)
+{
+        struct backlight_properties *props = &dev->props;
+
+        return props->brightness;
+}
+
+static struct backlight_ops bl_ops = {
+        .get_brightness         = tosa_bl_get_brightness,
+        .update_status          = tosa_bl_update_status,
+};
+
+static int __devinit tosa_bl_probe(struct i2c_client *client,
+                const struct i2c_device_id *id)
+{
+        struct tosa_bl_data *data = kzalloc(sizeof(struct tosa_bl_data), GFP_KERNEL);
+        int ret = 0;
+        if (!data)
+                return -ENOMEM;
+
+        data->comadj = sharpsl_param.comadj == -1 ? COMADJ_DEFAULT : sharpsl_param.comadj;
+
+        ret = gpio_request(TOSA_GPIO_BL_C20MA, "backlight");
+        if (ret) {
+                dev_dbg(&data->bl->dev, "Unable to request gpio!\n");
+                goto err_gpio_bl;
+        }
+        ret = gpio_direction_output(TOSA_GPIO_BL_C20MA, 0);
+        if (ret)
+                goto err_gpio_dir;
+
+        i2c_set_clientdata(client, data);
+        data->i2c = client;
+
+        data->bl = backlight_device_register("tosa-bl", &client->dev,
+                        data, &bl_ops);
+        if (IS_ERR(data->bl)) {
+                ret = PTR_ERR(data->bl);
+                goto err_reg;
+        }
+
+        data->bl->props.brightness = 69;
+        data->bl->props.max_brightness = 512 - 1;
+        data->bl->props.power = FB_BLANK_UNBLANK;
+
+        backlight_update_status(data->bl);
+
+        return 0;
+
+err_reg:
+        data->bl = NULL;
+        i2c_set_clientdata(client, NULL);
+err_gpio_dir:
+        gpio_free(TOSA_GPIO_BL_C20MA);
+err_gpio_bl:
+        kfree(data);
+        return ret;
+}
+
+static int __devexit tosa_bl_remove(struct i2c_client *client)
+{
+        struct tosa_bl_data *data = i2c_get_clientdata(client);
+
+        backlight_device_unregister(data->bl);
+        data->bl = NULL;
+        i2c_set_clientdata(client, NULL);
+
+        gpio_free(TOSA_GPIO_BL_C20MA);
+
+        kfree(data);
+
+        return 0;
+}
+
+#ifdef CONFIG_PM
+static int tosa_bl_suspend(struct i2c_client *client, pm_message_t pm)
+{
+        struct tosa_bl_data *data = i2c_get_clientdata(client);
+
+        tosa_bl_set_backlight(data, 0);
+
+        return 0;
+}
+
+static int tosa_bl_resume(struct i2c_client *client)
+{
+        struct tosa_bl_data *data = i2c_get_clientdata(client);
+
+        backlight_update_status(data->bl);
+        return 0;
+}
+#else
+#define tosa_bl_suspend NULL
+#define tosa_bl_resume NULL
+#endif
+
+static const struct i2c_device_id tosa_bl_id[] = {
+        { "tosa-bl", 0 },
+        { },
+};
+
+
+static struct i2c_driver tosa_bl_driver = {
+        .driver = {
+                .name           = "tosa-bl",
+                .owner          = THIS_MODULE,
+        },
+        .probe          = tosa_bl_probe,
+        .remove         = __devexit_p(tosa_bl_remove),
+        .suspend        = tosa_bl_suspend,
+        .resume         = tosa_bl_resume,
+        .id_table       = tosa_bl_id,
+};
+
+static int __init tosa_bl_init(void)
+{
+        return i2c_add_driver(&tosa_bl_driver);
+}
+
+static void __exit tosa_bl_exit(void)
+{
+        i2c_del_driver(&tosa_bl_driver);
+}
+
+module_init(tosa_bl_init);
+module_exit(tosa_bl_exit);
+
+MODULE_AUTHOR("Dmitry Baryshkov");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("LCD/Backlight control for Sharp SL-6000 PDA");
+
diff --git a/drivers/video/backlight/tosa_lcd.c b/drivers/video/backlight/tosa_lcd.c
new file mode 100644
index 000000000000..57a26649f1a5
--- /dev/null
+++ b/drivers/video/backlight/tosa_lcd.c
@@ -0,0 +1,280 @@
+/*
+ *  LCD / Backlight control code for Sharp SL-6000x (tosa)
+ *
+ *  Copyright (c) 2005          Dirk Opfer
+ *  Copyright (c) 2007,2008     Dmitry Baryshkov
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2 as
+ *  published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/spi/spi.h>
+#include <linux/i2c.h>
+#include <linux/gpio.h>
+#include <linux/delay.h>
+#include <linux/lcd.h>
+#include <linux/fb.h>
+
+#include <asm/mach/sharpsl_param.h>
+
+#include <mach/tosa.h>
+
+#define POWER_IS_ON(pwr)        ((pwr) <= FB_BLANK_NORMAL)
+
+#define TG_REG0_VQV     0x0001
+#define TG_REG0_COLOR   0x0002
+#define TG_REG0_UD      0x0004
+#define TG_REG0_LR      0x0008
+
+#define DAC_BASE        0x4e
+
+struct tosa_lcd_data {
+        struct spi_device *spi;
+        struct lcd_device *lcd;
+        struct i2c_client *i2c;
+
+        int lcd_power;
+};
+
+static int tosa_tg_send(struct spi_device *spi, int adrs, uint8_t data)
+{
+        u8 buf[1];
+        struct spi_message msg;
+        struct spi_transfer xfer = {
+                .len            = 1,
+                .cs_change      = 1,
+                .tx_buf         = buf,
+        };
+
+        buf[0] = ((adrs & 0x07) << 5) | (data & 0x1f);
+        spi_message_init(&msg);
+        spi_message_add_tail(&xfer, &msg);
+
+        return spi_sync(spi, &msg);
+}
+
+int tosa_bl_enable(struct spi_device *spi, int enable)
+{
+        /* bl_enable GP04=1 otherwise GP04=0*/
+        return tosa_tg_send(spi, TG_GPODR2, enable? 0x01 : 0x00);
+}
+EXPORT_SYMBOL(tosa_bl_enable);
+
+static void tosa_lcd_tg_init(struct tosa_lcd_data *data)
+{
+        /* TG on */
+        gpio_set_value(TOSA_GPIO_TG_ON, 0);
+
+        mdelay(60);
+
+        /* delayed 0clk TCTL signal for VGA */
+        tosa_tg_send(data->spi, TG_TPOSCTL, 0x00);
+        /* GPOS0=powercontrol, GPOS1=GPIO, GPOS2=TCTL */
+        tosa_tg_send(data->spi, TG_GPOSR, 0x02);
+}
+
+static void tosa_lcd_tg_on(struct tosa_lcd_data *data)
+{
+        struct spi_device *spi = data->spi;
+        const int value = TG_REG0_COLOR | TG_REG0_UD | TG_REG0_LR;
+        tosa_tg_send(spi, TG_PNLCTL, value | TG_REG0_VQV); /* this depends on mode */
+
+        /* TG LCD pannel power up */
+        tosa_tg_send(spi, TG_PINICTL,0x4);
+        mdelay(50);
+
+        /* TG LCD GVSS */
+        tosa_tg_send(spi, TG_PINICTL,0x0);
+
+        if (!data->i2c) {
+                /* after the pannel is powered up the first time, we can access the i2c bus */
+                /* so probe for the DAC */
+                struct i2c_adapter *adap = i2c_get_adapter(0);
+                struct i2c_board_info info = {
+                        .type   = "tosa-bl",
+                        .addr   = DAC_BASE,
+                        .platform_data = data->spi,
+                };
+                data->i2c = i2c_new_device(adap, &info);
+        }
+}
+
+static void tosa_lcd_tg_off(struct tosa_lcd_data *data)
+{
+        struct spi_device *spi = data->spi;
+
+        /* TG LCD VHSA off */
+        tosa_tg_send(spi, TG_PINICTL,0x4);
+        mdelay(50);
+
+        /* TG LCD signal off */
+        tosa_tg_send(spi, TG_PINICTL,0x6);
+        mdelay(50);
+
+        /* TG Off */
+        gpio_set_value(TOSA_GPIO_TG_ON, 1);
+        mdelay(100);
+}
+
+int tosa_lcd_set_power(struct lcd_device *lcd, int power)
+{
+        struct tosa_lcd_data *data = lcd_get_data(lcd);
+
+        if (POWER_IS_ON(power) && !POWER_IS_ON(data->lcd_power))
+                tosa_lcd_tg_on(data);
+
+        if (!POWER_IS_ON(power) && POWER_IS_ON(data->lcd_power))
+                tosa_lcd_tg_off(data);
+
+        data->lcd_power = power;
+        return 0;
+}
+
+static int tosa_lcd_get_power(struct lcd_device *lcd)
+{
+        struct tosa_lcd_data *data = lcd_get_data(lcd);
+
+        return data->lcd_power;
+}
+
+static struct lcd_ops tosa_lcd_ops = {
+        .set_power = tosa_lcd_set_power,
+        .get_power = tosa_lcd_get_power,
+};
+
+static int __devinit tosa_lcd_probe(struct spi_device *spi)
+{
+        int ret;
+        struct tosa_lcd_data *data;
+
+        data = kzalloc(sizeof(struct tosa_lcd_data), GFP_KERNEL);
+        if (!data)
+                return -ENOMEM;
+
+        /*
+         * bits_per_word cannot be configured in platform data
+         */
+        spi->bits_per_word = 8;
+
+        ret = spi_setup(spi);
+        if (ret < 0)
+                goto err_spi;
+
+        data->spi = spi;
+        dev_set_drvdata(&spi->dev, data);
+
+        ret = gpio_request(TOSA_GPIO_TG_ON, "tg #pwr");
+        if (ret < 0)
+                goto err_gpio_tg;
+
+        mdelay(60);
+
+        ret = gpio_direction_output(TOSA_GPIO_TG_ON, 0);
+        if (ret < 0)
+                goto err_gpio_dir;
+
+        mdelay(60);
+        tosa_lcd_tg_init(data);
+
+        tosa_lcd_tg_on(data);
+
+        data->lcd = lcd_device_register("tosa-lcd", &spi->dev, data,
+                        &tosa_lcd_ops);
+
+        if (IS_ERR(data->lcd)) {
+                ret = PTR_ERR(data->lcd);
+                data->lcd = NULL;
+                goto err_register;
+        }
+
+        return 0;
+
+err_register:
+        tosa_lcd_tg_off(data);
+err_gpio_dir:
+        gpio_free(TOSA_GPIO_TG_ON);
+err_gpio_tg:
+        dev_set_drvdata(&spi->dev, NULL);
+err_spi:
+        kfree(data);
+        return ret;
+}
+
+static int __devexit tosa_lcd_remove(struct spi_device *spi)
+{
+        struct tosa_lcd_data *data = dev_get_drvdata(&spi->dev);
+
+        lcd_device_unregister(data->lcd);
+
+        if (data->i2c)
+                i2c_unregister_device(data->i2c);
+
+        tosa_lcd_tg_off(data);
+
+        gpio_free(TOSA_GPIO_TG_ON);
+        dev_set_drvdata(&spi->dev, NULL);
+        kfree(data);
+
+        return 0;
+}
+
+#ifdef CONFIG_PM
+static int tosa_lcd_suspend(struct spi_device *spi, pm_message_t state)
+{
+        struct tosa_lcd_data *data = dev_get_drvdata(&spi->dev);
+
+        tosa_lcd_tg_off(data);
+
+        return 0;
+}
+
+static int tosa_lcd_resume(struct spi_device *spi)
+{
+        struct tosa_lcd_data *data = dev_get_drvdata(&spi->dev);
+
+        tosa_lcd_tg_init(data);
+        if (POWER_IS_ON(data->lcd_power))
+                tosa_lcd_tg_on(data);
+        else
+                tosa_lcd_tg_off(data);
+
+        return 0;
+}
+#else
+#define tosa_lcd_suspend        NULL
+#define tosa_lcd_reume NULL
+#endif
+
+static struct spi_driver tosa_lcd_driver = {
+        .driver = {
+                .name           = "tosa-lcd",
+                .owner          = THIS_MODULE,
+        },
+        .probe          = tosa_lcd_probe,
+        .remove         = __devexit_p(tosa_lcd_remove),
+        .suspend        = tosa_lcd_suspend,
+        .resume         = tosa_lcd_resume,
+};
+
+static int __init tosa_lcd_init(void)
+{
+        return spi_register_driver(&tosa_lcd_driver);
+}
+
+static void __exit tosa_lcd_exit(void)
+{
+        spi_unregister_driver(&tosa_lcd_driver);
+}
+
+module_init(tosa_lcd_init);
+module_exit(tosa_lcd_exit);
+
+MODULE_AUTHOR("Dmitry Baryshkov");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("LCD/Backlight control for Sharp SL-6000 PDA");
+