linux/drivers/video/backlight/tosa_lcd.c
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   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/slab.h>
  19#include <linux/gpio.h>
  20#include <linux/delay.h>
  21#include <linux/lcd.h>
  22#include <linux/fb.h>
  23
  24#include <asm/mach/sharpsl_param.h>
  25
  26#include <mach/tosa.h>
  27
  28#define POWER_IS_ON(pwr)        ((pwr) <= FB_BLANK_NORMAL)
  29
  30#define TG_REG0_VQV     0x0001
  31#define TG_REG0_COLOR   0x0002
  32#define TG_REG0_UD      0x0004
  33#define TG_REG0_LR      0x0008
  34
  35#define DAC_BASE        0x4e
  36
  37struct tosa_lcd_data {
  38        struct spi_device *spi;
  39        struct lcd_device *lcd;
  40        struct i2c_client *i2c;
  41
  42        int lcd_power;
  43        bool is_vga;
  44};
  45
  46static int tosa_tg_send(struct spi_device *spi, int adrs, uint8_t data)
  47{
  48        u8 buf[1];
  49        struct spi_message msg;
  50        struct spi_transfer xfer = {
  51                .len            = 1,
  52                .cs_change      = 1,
  53                .tx_buf         = buf,
  54        };
  55
  56        buf[0] = ((adrs & 0x07) << 5) | (data & 0x1f);
  57        spi_message_init(&msg);
  58        spi_message_add_tail(&xfer, &msg);
  59
  60        return spi_sync(spi, &msg);
  61}
  62
  63int tosa_bl_enable(struct spi_device *spi, int enable)
  64{
  65        /* bl_enable GP04=1 otherwise GP04=0*/
  66        return tosa_tg_send(spi, TG_GPODR2, enable ? 0x01 : 0x00);
  67}
  68EXPORT_SYMBOL(tosa_bl_enable);
  69
  70static void tosa_lcd_tg_init(struct tosa_lcd_data *data)
  71{
  72        /* TG on */
  73        gpio_set_value(TOSA_GPIO_TG_ON, 0);
  74
  75        mdelay(60);
  76
  77        /* delayed 0clk TCTL signal for VGA */
  78        tosa_tg_send(data->spi, TG_TPOSCTL, 0x00);
  79        /* GPOS0=powercontrol, GPOS1=GPIO, GPOS2=TCTL */
  80        tosa_tg_send(data->spi, TG_GPOSR, 0x02);
  81}
  82
  83static void tosa_lcd_tg_on(struct tosa_lcd_data *data)
  84{
  85        struct spi_device *spi = data->spi;
  86        int value = TG_REG0_COLOR | TG_REG0_UD | TG_REG0_LR;
  87
  88        if (data->is_vga)
  89                value |= TG_REG0_VQV;
  90
  91        tosa_tg_send(spi, TG_PNLCTL, value);
  92
  93        /* TG LCD pannel power up */
  94        tosa_tg_send(spi, TG_PINICTL, 0x4);
  95        mdelay(50);
  96
  97        /* TG LCD GVSS */
  98        tosa_tg_send(spi, TG_PINICTL, 0x0);
  99
 100        if (!data->i2c) {
 101                /*
 102                 * after the pannel is powered up the first time,
 103                 * we can access the i2c bus so probe for the DAC
 104                 */
 105                struct i2c_adapter *adap = i2c_get_adapter(0);
 106                struct i2c_board_info info = {
 107                        .type   = "tosa-bl",
 108                        .addr   = DAC_BASE,
 109                        .platform_data = data->spi,
 110                };
 111                data->i2c = i2c_new_device(adap, &info);
 112        }
 113}
 114
 115static void tosa_lcd_tg_off(struct tosa_lcd_data *data)
 116{
 117        struct spi_device *spi = data->spi;
 118
 119        /* TG LCD VHSA off */
 120        tosa_tg_send(spi, TG_PINICTL, 0x4);
 121        mdelay(50);
 122
 123        /* TG LCD signal off */
 124        tosa_tg_send(spi, TG_PINICTL, 0x6);
 125        mdelay(50);
 126
 127        /* TG Off */
 128        gpio_set_value(TOSA_GPIO_TG_ON, 1);
 129        mdelay(100);
 130}
 131
 132int tosa_lcd_set_power(struct lcd_device *lcd, int power)
 133{
 134        struct tosa_lcd_data *data = lcd_get_data(lcd);
 135
 136        if (POWER_IS_ON(power) && !POWER_IS_ON(data->lcd_power))
 137                tosa_lcd_tg_on(data);
 138
 139        if (!POWER_IS_ON(power) && POWER_IS_ON(data->lcd_power))
 140                tosa_lcd_tg_off(data);
 141
 142        data->lcd_power = power;
 143        return 0;
 144}
 145
 146static int tosa_lcd_get_power(struct lcd_device *lcd)
 147{
 148        struct tosa_lcd_data *data = lcd_get_data(lcd);
 149
 150        return data->lcd_power;
 151}
 152
 153static int tosa_lcd_set_mode(struct lcd_device *lcd, struct fb_videomode *mode)
 154{
 155        struct tosa_lcd_data *data = lcd_get_data(lcd);
 156
 157        if (mode->xres == 320 || mode->yres == 320)
 158                data->is_vga = false;
 159        else
 160                data->is_vga = true;
 161
 162        if (POWER_IS_ON(data->lcd_power))
 163                tosa_lcd_tg_on(data);
 164
 165        return 0;
 166}
 167
 168static struct lcd_ops tosa_lcd_ops = {
 169        .set_power = tosa_lcd_set_power,
 170        .get_power = tosa_lcd_get_power,
 171        .set_mode = tosa_lcd_set_mode,
 172};
 173
 174static int tosa_lcd_probe(struct spi_device *spi)
 175{
 176        int ret;
 177        struct tosa_lcd_data *data;
 178
 179        data = devm_kzalloc(&spi->dev, sizeof(struct tosa_lcd_data),
 180                                GFP_KERNEL);
 181        if (!data)
 182                return -ENOMEM;
 183
 184        data->is_vga = true; /* default to VGA mode */
 185
 186        /*
 187         * bits_per_word cannot be configured in platform data
 188         */
 189        spi->bits_per_word = 8;
 190
 191        ret = spi_setup(spi);
 192        if (ret < 0)
 193                return ret;
 194
 195        data->spi = spi;
 196        spi_set_drvdata(spi, data);
 197
 198        ret = devm_gpio_request_one(&spi->dev, TOSA_GPIO_TG_ON,
 199                                GPIOF_OUT_INIT_LOW, "tg #pwr");
 200        if (ret < 0)
 201                return ret;
 202
 203        mdelay(60);
 204
 205        tosa_lcd_tg_init(data);
 206
 207        tosa_lcd_tg_on(data);
 208
 209        data->lcd = devm_lcd_device_register(&spi->dev, "tosa-lcd", &spi->dev,
 210                                        data, &tosa_lcd_ops);
 211
 212        if (IS_ERR(data->lcd)) {
 213                ret = PTR_ERR(data->lcd);
 214                data->lcd = NULL;
 215                goto err_register;
 216        }
 217
 218        return 0;
 219
 220err_register:
 221        tosa_lcd_tg_off(data);
 222        return ret;
 223}
 224
 225static int tosa_lcd_remove(struct spi_device *spi)
 226{
 227        struct tosa_lcd_data *data = spi_get_drvdata(spi);
 228
 229        if (data->i2c)
 230                i2c_unregister_device(data->i2c);
 231
 232        tosa_lcd_tg_off(data);
 233
 234        return 0;
 235}
 236
 237#ifdef CONFIG_PM_SLEEP
 238static int tosa_lcd_suspend(struct device *dev)
 239{
 240        struct tosa_lcd_data *data = dev_get_drvdata(dev);
 241
 242        tosa_lcd_tg_off(data);
 243
 244        return 0;
 245}
 246
 247static int tosa_lcd_resume(struct device *dev)
 248{
 249        struct tosa_lcd_data *data = dev_get_drvdata(dev);
 250
 251        tosa_lcd_tg_init(data);
 252        if (POWER_IS_ON(data->lcd_power))
 253                tosa_lcd_tg_on(data);
 254        else
 255                tosa_lcd_tg_off(data);
 256
 257        return 0;
 258}
 259#endif
 260
 261static SIMPLE_DEV_PM_OPS(tosa_lcd_pm_ops, tosa_lcd_suspend, tosa_lcd_resume);
 262
 263static struct spi_driver tosa_lcd_driver = {
 264        .driver = {
 265                .name           = "tosa-lcd",
 266                .pm             = &tosa_lcd_pm_ops,
 267        },
 268        .probe          = tosa_lcd_probe,
 269        .remove         = tosa_lcd_remove,
 270};
 271
 272module_spi_driver(tosa_lcd_driver);
 273
 274MODULE_AUTHOR("Dmitry Baryshkov");
 275MODULE_LICENSE("GPL v2");
 276MODULE_DESCRIPTION("LCD/Backlight control for Sharp SL-6000 PDA");
 277MODULE_ALIAS("spi:tosa-lcd");
 278