drivers/video/backlight/ili9320.c

   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
  29 static 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
  54 int 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
  60 EXPORT_SYMBOL_GPL(ili9320_write);
  61
  62 int 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
  78 EXPORT_SYMBOL_GPL(ili9320_write_regs);
  79
  80 static 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
  94 static 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
 110 static 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
 121 static 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
 131 static 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
 150 static inline struct ili9320 *to_our_lcd(struct lcd_device *lcd)
 151 {
 152         return lcd_get_data(lcd);
 153 }
 154
 155 static 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
 162 static int ili9320_get_power(struct lcd_device *ld)
 163 {
 164         struct ili9320 *lcd = to_our_lcd(ld);
 165
 166         return lcd->power;
 167 }
 168
 169 static struct lcd_ops ili9320_ops = {
 170         .get_power      = ili9320_get_power,
 171         .set_power      = ili9320_set_power,
 172 };
 173
 174 static 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
 200 int __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 = devm_kzalloc(&spi->dev, 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                 return PTR_ERR(lcd);
 244         }
 245
 246         ili->lcd = lcd;
 247
 248         dev_info(dev, "initialising %s\n", client->name);
 249
 250         ret = ili9320_power(ili, FB_BLANK_UNBLANK);
 251         if (ret != 0) {
 252                 dev_err(dev, "failed to set lcd power state\n");
 253                 goto err_unregister;
 254         }
 255
 256         return 0;
 257
 258  err_unregister:
 259         lcd_device_unregister(lcd);
 260
 261         return ret;
 262 }
 263
 264 EXPORT_SYMBOL_GPL(ili9320_probe_spi);
 265
 266 int ili9320_remove(struct ili9320 *ili)
 267 {
 268         ili9320_power(ili, FB_BLANK_POWERDOWN);
 269
 270         lcd_device_unregister(ili->lcd);
 271
 272         return 0;
 273 }
 274
 275 EXPORT_SYMBOL_GPL(ili9320_remove);
 276
 277 #ifdef CONFIG_PM
 278 int ili9320_suspend(struct ili9320 *lcd, pm_message_t state)
 279 {
 280         int ret;
 281
 282         dev_dbg(lcd->dev, "%s: event %d\n", __func__, state.event);
 283
 284         if (state.event == PM_EVENT_SUSPEND) {
 285                 ret = ili9320_power(lcd, FB_BLANK_POWERDOWN);
 286
 287                 if (lcd->platdata->suspend == ILI9320_SUSPEND_DEEP) {
 288                         ili9320_write(lcd, ILI9320_POWER1, lcd->power1 |
 289                                       ILI9320_POWER1_SLP |
 290                                       ILI9320_POWER1_DSTB);
 291                         lcd->initialised = 0;
 292                 }
 293
 294                 return ret;
 295         }
 296
 297         return 0;
 298 }
 299
 300 EXPORT_SYMBOL_GPL(ili9320_suspend);
 301
 302 int ili9320_resume(struct ili9320 *lcd)
 303 {
 304         dev_info(lcd->dev, "resuming from power state %d\n", lcd->power);
 305
 306         if (lcd->platdata->suspend == ILI9320_SUSPEND_DEEP) {
 307                 ili9320_write(lcd, ILI9320_POWER1, 0x00);
 308         }
 309
 310         return ili9320_power(lcd, FB_BLANK_UNBLANK);
 311 }
 312
 313 EXPORT_SYMBOL_GPL(ili9320_resume);
 314 #endif
 315
 316 /* Power down all displays on reboot, poweroff or halt */
 317 void ili9320_shutdown(struct ili9320 *lcd)
 318 {
 319         ili9320_power(lcd, FB_BLANK_POWERDOWN);
 320 }
 321
 322 EXPORT_SYMBOL_GPL(ili9320_shutdown);
 323
 324 MODULE_AUTHOR("Ben Dooks <ben-linux@fluff.org>");
 325 MODULE_DESCRIPTION("ILI9320 LCD Driver");
 326 MODULE_LICENSE("GPL v2");