linux/drivers/video/backlight/tosa_lcd.c
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   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 *  LCD / Backlight control code for Sharp SL-6000x (tosa)
   4 *
   5 *  Copyright (c) 2005          Dirk Opfer
   6 *  Copyright (c) 2007,2008     Dmitry Baryshkov
   7 */
   8
   9#include <linux/kernel.h>
  10#include <linux/module.h>
  11#include <linux/device.h>
  12#include <linux/spi/spi.h>
  13#include <linux/i2c.h>
  14#include <linux/slab.h>
  15#include <linux/gpio/consumer.h>
  16#include <linux/delay.h>
  17#include <linux/lcd.h>
  18#include <linux/fb.h>
  19
  20#include <asm/mach/sharpsl_param.h>
  21
  22#include "tosa_bl.h"
  23
  24#define POWER_IS_ON(pwr)        ((pwr) <= FB_BLANK_NORMAL)
  25
  26#define TG_REG0_VQV     0x0001
  27#define TG_REG0_COLOR   0x0002
  28#define TG_REG0_UD      0x0004
  29#define TG_REG0_LR      0x0008
  30
  31/*
  32 * Timing Generator
  33 */
  34#define TG_PNLCTL       0x00
  35#define TG_TPOSCTL      0x01
  36#define TG_DUTYCTL      0x02
  37#define TG_GPOSR        0x03
  38#define TG_GPODR1       0x04
  39#define TG_GPODR2       0x05
  40#define TG_PINICTL      0x06
  41#define TG_HPOSCTL      0x07
  42
  43
  44#define DAC_BASE        0x4e
  45
  46struct tosa_lcd_data {
  47        struct spi_device *spi;
  48        struct lcd_device *lcd;
  49        struct i2c_client *i2c;
  50        struct gpio_desc *gpiod_tg;
  51
  52        int lcd_power;
  53        bool is_vga;
  54};
  55
  56static int tosa_tg_send(struct spi_device *spi, int adrs, uint8_t data)
  57{
  58        u8 buf[1];
  59        struct spi_message msg;
  60        struct spi_transfer xfer = {
  61                .len            = 1,
  62                .cs_change      = 0,
  63                .tx_buf         = buf,
  64        };
  65
  66        buf[0] = ((adrs & 0x07) << 5) | (data & 0x1f);
  67        spi_message_init(&msg);
  68        spi_message_add_tail(&xfer, &msg);
  69
  70        return spi_sync(spi, &msg);
  71}
  72
  73int tosa_bl_enable(struct spi_device *spi, int enable)
  74{
  75        /* bl_enable GP04=1 otherwise GP04=0*/
  76        return tosa_tg_send(spi, TG_GPODR2, enable ? 0x01 : 0x00);
  77}
  78EXPORT_SYMBOL(tosa_bl_enable);
  79
  80static void tosa_lcd_tg_init(struct tosa_lcd_data *data)
  81{
  82        /* TG on */
  83        gpiod_set_value(data->gpiod_tg, 0);
  84
  85        mdelay(60);
  86
  87        /* delayed 0clk TCTL signal for VGA */
  88        tosa_tg_send(data->spi, TG_TPOSCTL, 0x00);
  89        /* GPOS0=powercontrol, GPOS1=GPIO, GPOS2=TCTL */
  90        tosa_tg_send(data->spi, TG_GPOSR, 0x02);
  91}
  92
  93static void tosa_lcd_tg_on(struct tosa_lcd_data *data)
  94{
  95        struct spi_device *spi = data->spi;
  96        int value = TG_REG0_COLOR | TG_REG0_UD | TG_REG0_LR;
  97
  98        if (data->is_vga)
  99                value |= TG_REG0_VQV;
 100
 101        tosa_tg_send(spi, TG_PNLCTL, value);
 102
 103        /* TG LCD pannel power up */
 104        tosa_tg_send(spi, TG_PINICTL, 0x4);
 105        mdelay(50);
 106
 107        /* TG LCD GVSS */
 108        tosa_tg_send(spi, TG_PINICTL, 0x0);
 109
 110        if (IS_ERR_OR_NULL(data->i2c)) {
 111                /*
 112                 * after the pannel is powered up the first time,
 113                 * we can access the i2c bus so probe for the DAC
 114                 */
 115                struct i2c_adapter *adap = i2c_get_adapter(0);
 116                struct i2c_board_info info = {
 117                        .dev_name = "tosa-bl",
 118                        .type   = "tosa-bl",
 119                        .addr   = DAC_BASE,
 120                        .platform_data = data->spi,
 121                };
 122                data->i2c = i2c_new_client_device(adap, &info);
 123        }
 124}
 125
 126static void tosa_lcd_tg_off(struct tosa_lcd_data *data)
 127{
 128        struct spi_device *spi = data->spi;
 129
 130        /* TG LCD VHSA off */
 131        tosa_tg_send(spi, TG_PINICTL, 0x4);
 132        mdelay(50);
 133
 134        /* TG LCD signal off */
 135        tosa_tg_send(spi, TG_PINICTL, 0x6);
 136        mdelay(50);
 137
 138        /* TG Off */
 139        gpiod_set_value(data->gpiod_tg, 1);
 140        mdelay(100);
 141}
 142
 143int tosa_lcd_set_power(struct lcd_device *lcd, int power)
 144{
 145        struct tosa_lcd_data *data = lcd_get_data(lcd);
 146
 147        if (POWER_IS_ON(power) && !POWER_IS_ON(data->lcd_power))
 148                tosa_lcd_tg_on(data);
 149
 150        if (!POWER_IS_ON(power) && POWER_IS_ON(data->lcd_power))
 151                tosa_lcd_tg_off(data);
 152
 153        data->lcd_power = power;
 154        return 0;
 155}
 156
 157static int tosa_lcd_get_power(struct lcd_device *lcd)
 158{
 159        struct tosa_lcd_data *data = lcd_get_data(lcd);
 160
 161        return data->lcd_power;
 162}
 163
 164static int tosa_lcd_set_mode(struct lcd_device *lcd, struct fb_videomode *mode)
 165{
 166        struct tosa_lcd_data *data = lcd_get_data(lcd);
 167
 168        if (mode->xres == 320 || mode->yres == 320)
 169                data->is_vga = false;
 170        else
 171                data->is_vga = true;
 172
 173        if (POWER_IS_ON(data->lcd_power))
 174                tosa_lcd_tg_on(data);
 175
 176        return 0;
 177}
 178
 179static struct lcd_ops tosa_lcd_ops = {
 180        .set_power = tosa_lcd_set_power,
 181        .get_power = tosa_lcd_get_power,
 182        .set_mode = tosa_lcd_set_mode,
 183};
 184
 185static int tosa_lcd_probe(struct spi_device *spi)
 186{
 187        int ret;
 188        struct tosa_lcd_data *data;
 189
 190        data = devm_kzalloc(&spi->dev, sizeof(struct tosa_lcd_data),
 191                                GFP_KERNEL);
 192        if (!data)
 193                return -ENOMEM;
 194
 195        data->is_vga = true; /* default to VGA mode */
 196
 197        /*
 198         * bits_per_word cannot be configured in platform data
 199         */
 200        spi->bits_per_word = 8;
 201
 202        ret = spi_setup(spi);
 203        if (ret < 0)
 204                return ret;
 205
 206        data->spi = spi;
 207        spi_set_drvdata(spi, data);
 208
 209        data->gpiod_tg = devm_gpiod_get(&spi->dev, "tg #pwr", GPIOD_OUT_LOW);
 210        if (IS_ERR(data->gpiod_tg))
 211                return PTR_ERR(data->gpiod_tg);
 212
 213        mdelay(60);
 214
 215        tosa_lcd_tg_init(data);
 216
 217        tosa_lcd_tg_on(data);
 218
 219        data->lcd = devm_lcd_device_register(&spi->dev, "tosa-lcd", &spi->dev,
 220                                        data, &tosa_lcd_ops);
 221
 222        if (IS_ERR(data->lcd)) {
 223                ret = PTR_ERR(data->lcd);
 224                data->lcd = NULL;
 225                goto err_register;
 226        }
 227
 228        return 0;
 229
 230err_register:
 231        tosa_lcd_tg_off(data);
 232        return ret;
 233}
 234
 235static int tosa_lcd_remove(struct spi_device *spi)
 236{
 237        struct tosa_lcd_data *data = spi_get_drvdata(spi);
 238
 239        i2c_unregister_device(data->i2c);
 240
 241        tosa_lcd_tg_off(data);
 242
 243        return 0;
 244}
 245
 246#ifdef CONFIG_PM_SLEEP
 247static int tosa_lcd_suspend(struct device *dev)
 248{
 249        struct tosa_lcd_data *data = dev_get_drvdata(dev);
 250
 251        tosa_lcd_tg_off(data);
 252
 253        return 0;
 254}
 255
 256static int tosa_lcd_resume(struct device *dev)
 257{
 258        struct tosa_lcd_data *data = dev_get_drvdata(dev);
 259
 260        tosa_lcd_tg_init(data);
 261        if (POWER_IS_ON(data->lcd_power))
 262                tosa_lcd_tg_on(data);
 263        else
 264                tosa_lcd_tg_off(data);
 265
 266        return 0;
 267}
 268#endif
 269
 270static SIMPLE_DEV_PM_OPS(tosa_lcd_pm_ops, tosa_lcd_suspend, tosa_lcd_resume);
 271
 272static struct spi_driver tosa_lcd_driver = {
 273        .driver = {
 274                .name           = "tosa-lcd",
 275                .pm             = &tosa_lcd_pm_ops,
 276        },
 277        .probe          = tosa_lcd_probe,
 278        .remove         = tosa_lcd_remove,
 279};
 280
 281module_spi_driver(tosa_lcd_driver);
 282
 283MODULE_AUTHOR("Dmitry Baryshkov");
 284MODULE_LICENSE("GPL v2");
 285MODULE_DESCRIPTION("LCD/Backlight control for Sharp SL-6000 PDA");
 286MODULE_ALIAS("spi:tosa-lcd");
 287