linux/drivers/video/backlight/ili9320.c
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   1/* drivers/video/backlight/ili9320.c
   2 *
   3 * ILI9320 LCD controller driver core.
   4 *
   5 * Copyright 2007 Simtec Electronics
   6 *      http://armlinux.simtec.co.uk/
   7 *      Ben Dooks <ben@simtec.co.uk>
   8 *
   9 * This program is free software; you can redistribute it and/or modify
  10 * it under the terms of the GNU General Public License version 2 as
  11 * published by the Free Software Foundation.
  12*/
  13
  14#include <linux/delay.h>
  15#include <linux/err.h>
  16#include <linux/fb.h>
  17#include <linux/init.h>
  18#include <linux/lcd.h>
  19#include <linux/module.h>
  20#include <linux/slab.h>
  21
  22#include <linux/spi/spi.h>
  23
  24#include <video/ili9320.h>
  25
  26#include "ili9320.h"
  27
  28
  29static inline int ili9320_write_spi(struct ili9320 *ili,
  30                                    unsigned int reg,
  31                                    unsigned int value)
  32{
  33        struct ili9320_spi *spi = &ili->access.spi;
  34        unsigned char *addr = spi->buffer_addr;
  35        unsigned char *data = spi->buffer_data;
  36
  37        /* spi message consits of:
  38         * first byte: ID and operation
  39         */
  40
  41        addr[0] = spi->id | ILI9320_SPI_INDEX | ILI9320_SPI_WRITE;
  42        addr[1] = reg >> 8;
  43        addr[2] = reg;
  44
  45        /* second message is the data to transfer */
  46
  47        data[0] = spi->id | ILI9320_SPI_DATA  | ILI9320_SPI_WRITE;
  48        data[1] = value >> 8;
  49        data[2] = value;
  50
  51        return spi_sync(spi->dev, &spi->message);
  52}
  53
  54int ili9320_write(struct ili9320 *ili, unsigned int reg, unsigned int value)
  55{
  56        dev_dbg(ili->dev, "write: reg=%02x, val=%04x\n", reg, value);
  57        return ili->write(ili, reg, value);
  58}
  59
  60EXPORT_SYMBOL_GPL(ili9320_write);
  61
  62int ili9320_write_regs(struct ili9320 *ili,
  63                       struct ili9320_reg *values,
  64                       int nr_values)
  65{
  66        int index;
  67        int ret;
  68
  69        for (index = 0; index < nr_values; index++, values++) {
  70                ret = ili9320_write(ili, values->address, values->value);
  71                if (ret != 0)
  72                        return ret;
  73        }
  74
  75        return 0;
  76}
  77
  78EXPORT_SYMBOL_GPL(ili9320_write_regs);
  79
  80static void ili9320_reset(struct ili9320 *lcd)
  81{
  82        struct ili9320_platdata *cfg = lcd->platdata;
  83
  84        cfg->reset(1);
  85        mdelay(50);
  86
  87        cfg->reset(0);
  88        mdelay(50);
  89
  90        cfg->reset(1);
  91        mdelay(100);
  92}
  93
  94static inline int ili9320_init_chip(struct ili9320 *lcd)
  95{
  96        int ret;
  97
  98        ili9320_reset(lcd);
  99
 100        ret = lcd->client->init(lcd, lcd->platdata);
 101        if (ret != 0) {
 102                dev_err(lcd->dev, "failed to initialise display\n");
 103                return ret;
 104        }
 105
 106        lcd->initialised = 1;
 107        return 0;
 108}
 109
 110static inline int ili9320_power_on(struct ili9320 *lcd)
 111{
 112        if (!lcd->initialised)
 113                ili9320_init_chip(lcd);
 114
 115        lcd->display1 |= (ILI9320_DISPLAY1_D(3) | ILI9320_DISPLAY1_BASEE);
 116        ili9320_write(lcd, ILI9320_DISPLAY1, lcd->display1);
 117
 118        return 0;
 119}
 120
 121static inline int ili9320_power_off(struct ili9320 *lcd)
 122{
 123        lcd->display1 &= ~(ILI9320_DISPLAY1_D(3) | ILI9320_DISPLAY1_BASEE);
 124        ili9320_write(lcd, ILI9320_DISPLAY1, lcd->display1);
 125
 126        return 0;
 127}
 128
 129#define POWER_IS_ON(pwr)        ((pwr) <= FB_BLANK_NORMAL)
 130
 131static int ili9320_power(struct ili9320 *lcd, int power)
 132{
 133        int ret = 0;
 134
 135        dev_dbg(lcd->dev, "power %d => %d\n", lcd->power, power);
 136
 137        if (POWER_IS_ON(power) && !POWER_IS_ON(lcd->power))
 138                ret = ili9320_power_on(lcd);
 139        else if (!POWER_IS_ON(power) && POWER_IS_ON(lcd->power))
 140                ret = ili9320_power_off(lcd);
 141
 142        if (ret == 0)
 143                lcd->power = power;
 144        else
 145                dev_warn(lcd->dev, "failed to set power mode %d\n", power);
 146
 147        return ret;
 148}
 149
 150static inline struct ili9320 *to_our_lcd(struct lcd_device *lcd)
 151{
 152        return lcd_get_data(lcd);
 153}
 154
 155static int ili9320_set_power(struct lcd_device *ld, int power)
 156{
 157        struct ili9320 *lcd = to_our_lcd(ld);
 158
 159        return ili9320_power(lcd, power);
 160}
 161
 162static int ili9320_get_power(struct lcd_device *ld)
 163{
 164        struct ili9320 *lcd = to_our_lcd(ld);
 165
 166        return lcd->power;
 167}
 168
 169static struct lcd_ops ili9320_ops = {
 170        .get_power      = ili9320_get_power,
 171        .set_power      = ili9320_set_power,
 172};
 173
 174static void __devinit ili9320_setup_spi(struct ili9320 *ili,
 175                                        struct spi_device *dev)
 176{
 177        struct ili9320_spi *spi = &ili->access.spi;
 178
 179        ili->write = ili9320_write_spi;
 180        spi->dev = dev;
 181
 182        /* fill the two messages we are going to use to send the data
 183         * with, the first the address followed by the data. The datasheet
 184         * says they should be done as two distinct cycles of the SPI CS line.
 185         */
 186
 187        spi->xfer[0].tx_buf = spi->buffer_addr;
 188        spi->xfer[1].tx_buf = spi->buffer_data;
 189        spi->xfer[0].len = 3;
 190        spi->xfer[1].len = 3;
 191        spi->xfer[0].bits_per_word = 8;
 192        spi->xfer[1].bits_per_word = 8;
 193        spi->xfer[0].cs_change = 1;
 194
 195        spi_message_init(&spi->message);
 196        spi_message_add_tail(&spi->xfer[0], &spi->message);
 197        spi_message_add_tail(&spi->xfer[1], &spi->message);
 198}
 199
 200int __devinit ili9320_probe_spi(struct spi_device *spi,
 201                                struct ili9320_client *client)
 202{
 203        struct ili9320_platdata *cfg = spi->dev.platform_data;
 204        struct device *dev = &spi->dev;
 205        struct ili9320 *ili;
 206        struct lcd_device *lcd;
 207        int ret = 0;
 208
 209        /* verify we where given some information */
 210
 211        if (cfg == NULL) {
 212                dev_err(dev, "no platform data supplied\n");
 213                return -EINVAL;
 214        }
 215
 216        if (cfg->hsize <= 0 || cfg->vsize <= 0 || cfg->reset == NULL) {
 217                dev_err(dev, "invalid platform data supplied\n");
 218                return -EINVAL;
 219        }
 220
 221        /* allocate and initialse our state */
 222
 223        ili = kzalloc(sizeof(struct ili9320), GFP_KERNEL);
 224        if (ili == NULL) {
 225                dev_err(dev, "no memory for device\n");
 226                return -ENOMEM;
 227        }
 228
 229        ili->access.spi.id = ILI9320_SPI_IDCODE | ILI9320_SPI_ID(1);
 230
 231        ili->dev = dev;
 232        ili->client = client;
 233        ili->power = FB_BLANK_POWERDOWN;
 234        ili->platdata = cfg;
 235
 236        dev_set_drvdata(&spi->dev, ili);
 237
 238        ili9320_setup_spi(ili, spi);
 239
 240        lcd = lcd_device_register("ili9320", dev, ili, &ili9320_ops);
 241        if (IS_ERR(lcd)) {
 242                dev_err(dev, "failed to register lcd device\n");
 243                ret = PTR_ERR(lcd);
 244                goto err_free;
 245        }
 246
 247        ili->lcd = lcd;
 248
 249        dev_info(dev, "initialising %s\n", client->name);
 250
 251        ret = ili9320_power(ili, FB_BLANK_UNBLANK);
 252        if (ret != 0) {
 253                dev_err(dev, "failed to set lcd power state\n");
 254                goto err_unregister;
 255        }
 256
 257        return 0;
 258
 259 err_unregister:
 260        lcd_device_unregister(lcd);
 261
 262 err_free:
 263        kfree(ili);
 264
 265        return ret;
 266}
 267
 268EXPORT_SYMBOL_GPL(ili9320_probe_spi);
 269
 270int __devexit ili9320_remove(struct ili9320 *ili)
 271{
 272        ili9320_power(ili, FB_BLANK_POWERDOWN);
 273
 274        lcd_device_unregister(ili->lcd);
 275        kfree(ili);
 276
 277        return 0;
 278}
 279
 280EXPORT_SYMBOL_GPL(ili9320_remove);
 281
 282#ifdef CONFIG_PM
 283int ili9320_suspend(struct ili9320 *lcd, pm_message_t state)
 284{
 285        int ret;
 286
 287        dev_dbg(lcd->dev, "%s: event %d\n", __func__, state.event);
 288
 289        if (state.event == PM_EVENT_SUSPEND) {
 290                ret = ili9320_power(lcd, FB_BLANK_POWERDOWN);
 291
 292                if (lcd->platdata->suspend == ILI9320_SUSPEND_DEEP) {
 293                        ili9320_write(lcd, ILI9320_POWER1, lcd->power1 |
 294                                      ILI9320_POWER1_SLP |
 295                                      ILI9320_POWER1_DSTB);
 296                        lcd->initialised = 0;
 297                }
 298
 299                return ret;
 300        }
 301
 302        return 0;
 303}
 304
 305EXPORT_SYMBOL_GPL(ili9320_suspend);
 306
 307int ili9320_resume(struct ili9320 *lcd)
 308{
 309        dev_info(lcd->dev, "resuming from power state %d\n", lcd->power);
 310
 311        if (lcd->platdata->suspend == ILI9320_SUSPEND_DEEP) {
 312                ili9320_write(lcd, ILI9320_POWER1, 0x00);
 313        }
 314
 315        return ili9320_power(lcd, FB_BLANK_UNBLANK);
 316}
 317
 318EXPORT_SYMBOL_GPL(ili9320_resume);
 319#endif
 320
 321/* Power down all displays on reboot, poweroff or halt */
 322void ili9320_shutdown(struct ili9320 *lcd)
 323{
 324        ili9320_power(lcd, FB_BLANK_POWERDOWN);
 325}
 326
 327EXPORT_SYMBOL_GPL(ili9320_shutdown);
 328
 329MODULE_AUTHOR("Ben Dooks <ben-linux@fluff.org>");
 330MODULE_DESCRIPTION("ILI9320 LCD Driver");
 331MODULE_LICENSE("GPL v2");
 332