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