1/* 2 * LCD / Backlight control code for Sharp SL-6000x (tosa) 3 * 4 * Copyright (c) 2005 Dirk Opfer 5 * Copyright (c) 2007,2008 Dmitry Baryshkov 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License version 2 as 9 * published by the Free Software Foundation. 10 * 11 */ 12 13#include <linux/kernel.h> 14#include <linux/module.h> 15#include <linux/device.h> 16#include <linux/spi/spi.h> 17#include <linux/i2c.h> 18#include <linux/gpio.h> 19#include <linux/fb.h> 20#include <linux/backlight.h> 21#include <linux/slab.h> 22 23#include <asm/mach/sharpsl_param.h> 24 25#include <mach/tosa.h> 26 27#define COMADJ_DEFAULT 97 28 29#define DAC_CH1 0 30#define DAC_CH2 1 31 32struct tosa_bl_data { 33 struct i2c_client *i2c; 34 struct backlight_device *bl; 35 36 int comadj; 37}; 38 39static void tosa_bl_set_backlight(struct tosa_bl_data *data, int brightness) 40{ 41 struct spi_device *spi = data->i2c->dev.platform_data; 42 43 i2c_smbus_write_byte_data(data->i2c, DAC_CH1, data->comadj); 44 45 /* SetBacklightDuty */ 46 i2c_smbus_write_byte_data(data->i2c, DAC_CH2, (u8)(brightness & 0xff)); 47 48 /* SetBacklightVR */ 49 gpio_set_value(TOSA_GPIO_BL_C20MA, brightness & 0x100); 50 51 tosa_bl_enable(spi, brightness); 52} 53 54static int tosa_bl_update_status(struct backlight_device *dev) 55{ 56 struct backlight_properties *props = &dev->props; 57 struct tosa_bl_data *data = dev_get_drvdata(&dev->dev); 58 int power = max(props->power, props->fb_blank); 59 int brightness = props->brightness; 60 61 if (power) 62 brightness = 0; 63 64 tosa_bl_set_backlight(data, brightness); 65 66 return 0; 67} 68 69static int tosa_bl_get_brightness(struct backlight_device *dev) 70{ 71 struct backlight_properties *props = &dev->props; 72 73 return props->brightness; 74} 75 76static const struct backlight_ops bl_ops = { 77 .get_brightness = tosa_bl_get_brightness, 78 .update_status = tosa_bl_update_status, 79}; 80 81static int __devinit tosa_bl_probe(struct i2c_client *client, 82 const struct i2c_device_id *id) 83{ 84 struct backlight_properties props; 85 struct tosa_bl_data *data = kzalloc(sizeof(struct tosa_bl_data), GFP_KERNEL); 86 int ret = 0; 87 if (!data) 88 return -ENOMEM; 89 90 data->comadj = sharpsl_param.comadj == -1 ? COMADJ_DEFAULT : sharpsl_param.comadj; 91 92 ret = gpio_request(TOSA_GPIO_BL_C20MA, "backlight"); 93 if (ret) { 94 dev_dbg(&data->bl->dev, "Unable to request gpio!\n"); 95 goto err_gpio_bl; 96 } 97 ret = gpio_direction_output(TOSA_GPIO_BL_C20MA, 0); 98 if (ret) 99 goto err_gpio_dir; 100 101 i2c_set_clientdata(client, data); 102 data->i2c = client; 103 104 memset(&props, 0, sizeof(struct backlight_properties)); 105 props.max_brightness = 512 - 1; 106 data->bl = backlight_device_register("tosa-bl", &client->dev, data, 107 &bl_ops, &props); 108 if (IS_ERR(data->bl)) { 109 ret = PTR_ERR(data->bl); 110 goto err_reg; 111 } 112 113 data->bl->props.brightness = 69; 114 data->bl->props.power = FB_BLANK_UNBLANK; 115 116 backlight_update_status(data->bl); 117 118 return 0; 119 120err_reg: 121 data->bl = NULL; 122err_gpio_dir: 123 gpio_free(TOSA_GPIO_BL_C20MA); 124err_gpio_bl: 125 kfree(data); 126 return ret; 127} 128 129static int __devexit tosa_bl_remove(struct i2c_client *client) 130{ 131 struct tosa_bl_data *data = i2c_get_clientdata(client); 132 133 backlight_device_unregister(data->bl); 134 data->bl = NULL; 135 136 gpio_free(TOSA_GPIO_BL_C20MA); 137 138 kfree(data); 139 140 return 0; 141} 142 143#ifdef CONFIG_PM 144static int tosa_bl_suspend(struct i2c_client *client, pm_message_t pm) 145{ 146 struct tosa_bl_data *data = i2c_get_clientdata(client); 147 148 tosa_bl_set_backlight(data, 0); 149 150 return 0; 151} 152 153static int tosa_bl_resume(struct i2c_client *client) 154{ 155 struct tosa_bl_data *data = i2c_get_clientdata(client); 156 157 backlight_update_status(data->bl); 158 return 0; 159} 160#else 161#define tosa_bl_suspend NULL 162#define tosa_bl_resume NULL 163#endif 164 165static const struct i2c_device_id tosa_bl_id[] = { 166 { "tosa-bl", 0 }, 167 { }, 168}; 169 170 171static struct i2c_driver tosa_bl_driver = { 172 .driver = { 173 .name = "tosa-bl", 174 .owner = THIS_MODULE, 175 }, 176 .probe = tosa_bl_probe, 177 .remove = __devexit_p(tosa_bl_remove), 178 .suspend = tosa_bl_suspend, 179 .resume = tosa_bl_resume, 180 .id_table = tosa_bl_id, 181}; 182 183static int __init tosa_bl_init(void) 184{ 185 return i2c_add_driver(&tosa_bl_driver); 186} 187 188static void __exit tosa_bl_exit(void) 189{ 190 i2c_del_driver(&tosa_bl_driver); 191} 192 193module_init(tosa_bl_init); 194module_exit(tosa_bl_exit); 195 196MODULE_AUTHOR("Dmitry Baryshkov"); 197MODULE_LICENSE("GPL v2"); 198MODULE_DESCRIPTION("LCD/Backlight control for Sharp SL-6000 PDA"); 199