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 EXPORT_SYMBOL_GPL(ili9320_write);
  60
  61 int ili9320_write_regs(struct ili9320 *ili,
  62                        const 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 EXPORT_SYMBOL_GPL(ili9320_write_regs);
  77
  78 static void ili9320_reset(struct ili9320 *lcd)
  79 {
  80         struct ili9320_platdata *cfg = lcd->platdata;
  81
  82         cfg->reset(1);
  83         mdelay(50);
  84
  85         cfg->reset(0);
  86         mdelay(50);
  87
  88         cfg->reset(1);
  89         mdelay(100);
  90 }
  91
  92 static inline int ili9320_init_chip(struct ili9320 *lcd)
  93 {
  94         int ret;
  95
  96         ili9320_reset(lcd);
  97
  98         ret = lcd->client->init(lcd, lcd->platdata);
  99         if (ret != 0) {
 100                 dev_err(lcd->dev, "failed to initialise display\n");
 101                 return ret;
 102         }
 103
 104         lcd->initialised = 1;
 105         return 0;
 106 }
 107
 108 static inline int ili9320_power_on(struct ili9320 *lcd)
 109 {
 110         if (!lcd->initialised)
 111                 ili9320_init_chip(lcd);
 112
 113         lcd->display1 |= (ILI9320_DISPLAY1_D(3) | ILI9320_DISPLAY1_BASEE);
 114         ili9320_write(lcd, ILI9320_DISPLAY1, lcd->display1);
 115
 116         return 0;
 117 }
 118
 119 static inline int ili9320_power_off(struct ili9320 *lcd)
 120 {
 121         lcd->display1 &= ~(ILI9320_DISPLAY1_D(3) | ILI9320_DISPLAY1_BASEE);
 122         ili9320_write(lcd, ILI9320_DISPLAY1, lcd->display1);
 123
 124         return 0;
 125 }
 126
 127 #define POWER_IS_ON(pwr)        ((pwr) <= FB_BLANK_NORMAL)
 128
 129 static int ili9320_power(struct ili9320 *lcd, int power)
 130 {
 131         int ret = 0;
 132
 133         dev_dbg(lcd->dev, "power %d => %d\n", lcd->power, power);
 134
 135         if (POWER_IS_ON(power) && !POWER_IS_ON(lcd->power))
 136                 ret = ili9320_power_on(lcd);
 137         else if (!POWER_IS_ON(power) && POWER_IS_ON(lcd->power))
 138                 ret = ili9320_power_off(lcd);
 139
 140         if (ret == 0)
 141                 lcd->power = power;
 142         else
 143                 dev_warn(lcd->dev, "failed to set power mode %d\n", power);
 144
 145         return ret;
 146 }
 147
 148 static inline struct ili9320 *to_our_lcd(struct lcd_device *lcd)
 149 {
 150         return lcd_get_data(lcd);
 151 }
 152
 153 static int ili9320_set_power(struct lcd_device *ld, int power)
 154 {
 155         struct ili9320 *lcd = to_our_lcd(ld);
 156
 157         return ili9320_power(lcd, power);
 158 }
 159
 160 static int ili9320_get_power(struct lcd_device *ld)
 161 {
 162         struct ili9320 *lcd = to_our_lcd(ld);
 163
 164         return lcd->power;
 165 }
 166
 167 static struct lcd_ops ili9320_ops = {
 168         .get_power      = ili9320_get_power,
 169         .set_power      = ili9320_set_power,
 170 };
 171
 172 static void ili9320_setup_spi(struct ili9320 *ili,
 173                                         struct spi_device *dev)
 174 {
 175         struct ili9320_spi *spi = &ili->access.spi;
 176
 177         ili->write = ili9320_write_spi;
 178         spi->dev = dev;
 179
 180         /* fill the two messages we are going to use to send the data
 181          * with, the first the address followed by the data. The datasheet
 182          * says they should be done as two distinct cycles of the SPI CS line.
 183          */
 184
 185         spi->xfer[0].tx_buf = spi->buffer_addr;
 186         spi->xfer[1].tx_buf = spi->buffer_data;
 187         spi->xfer[0].len = 3;
 188         spi->xfer[1].len = 3;
 189         spi->xfer[0].bits_per_word = 8;
 190         spi->xfer[1].bits_per_word = 8;
 191         spi->xfer[0].cs_change = 1;
 192
 193         spi_message_init(&spi->message);
 194         spi_message_add_tail(&spi->xfer[0], &spi->message);
 195         spi_message_add_tail(&spi->xfer[1], &spi->message);
 196 }
 197
 198 int ili9320_probe_spi(struct spi_device *spi,
 199                                 struct ili9320_client *client)
 200 {
 201         struct ili9320_platdata *cfg = spi->dev.platform_data;
 202         struct device *dev = &spi->dev;
 203         struct ili9320 *ili;
 204         struct lcd_device *lcd;
 205         int ret = 0;
 206
 207         /* verify we where given some information */
 208
 209         if (cfg == NULL) {
 210                 dev_err(dev, "no platform data supplied\n");
 211                 return -EINVAL;
 212         }
 213
 214         if (cfg->hsize <= 0 || cfg->vsize <= 0 || cfg->reset == NULL) {
 215                 dev_err(dev, "invalid platform data supplied\n");
 216                 return -EINVAL;
 217         }
 218
 219         /* allocate and initialse our state */
 220
 221         ili = devm_kzalloc(&spi->dev, sizeof(struct ili9320), GFP_KERNEL);
 222         if (ili == NULL) {
 223                 dev_err(dev, "no memory for device\n");
 224                 return -ENOMEM;
 225         }
 226
 227         ili->access.spi.id = ILI9320_SPI_IDCODE | ILI9320_SPI_ID(1);
 228
 229         ili->dev = dev;
 230         ili->client = client;
 231         ili->power = FB_BLANK_POWERDOWN;
 232         ili->platdata = cfg;
 233
 234         spi_set_drvdata(spi, ili);
 235
 236         ili9320_setup_spi(ili, spi);
 237
 238         lcd = lcd_device_register("ili9320", dev, ili, &ili9320_ops);
 239         if (IS_ERR(lcd)) {
 240                 dev_err(dev, "failed to register lcd device\n");
 241                 return PTR_ERR(lcd);
 242         }
 243
 244         ili->lcd = lcd;
 245
 246         dev_info(dev, "initialising %s\n", client->name);
 247
 248         ret = ili9320_power(ili, FB_BLANK_UNBLANK);
 249         if (ret != 0) {
 250                 dev_err(dev, "failed to set lcd power state\n");
 251                 goto err_unregister;
 252         }
 253
 254         return 0;
 255
 256  err_unregister:
 257         lcd_device_unregister(lcd);
 258
 259         return ret;
 260 }
 261 EXPORT_SYMBOL_GPL(ili9320_probe_spi);
 262
 263 int ili9320_remove(struct ili9320 *ili)
 264 {
 265         ili9320_power(ili, FB_BLANK_POWERDOWN);
 266
 267         lcd_device_unregister(ili->lcd);
 268
 269         return 0;
 270 }
 271 EXPORT_SYMBOL_GPL(ili9320_remove);
 272
 273 #ifdef CONFIG_PM_SLEEP
 274 int ili9320_suspend(struct ili9320 *lcd)
 275 {
 276         int ret;
 277
 278         ret = ili9320_power(lcd, FB_BLANK_POWERDOWN);
 279
 280         if (lcd->platdata->suspend == ILI9320_SUSPEND_DEEP) {
 281                 ili9320_write(lcd, ILI9320_POWER1, lcd->power1 |
 282                               ILI9320_POWER1_SLP |
 283                               ILI9320_POWER1_DSTB);
 284                 lcd->initialised = 0;
 285         }
 286
 287         return ret;
 288 }
 289 EXPORT_SYMBOL_GPL(ili9320_suspend);
 290
 291 int ili9320_resume(struct ili9320 *lcd)
 292 {
 293         dev_info(lcd->dev, "resuming from power state %d\n", lcd->power);
 294
 295         if (lcd->platdata->suspend == ILI9320_SUSPEND_DEEP)
 296                 ili9320_write(lcd, ILI9320_POWER1, 0x00);
 297
 298         return ili9320_power(lcd, FB_BLANK_UNBLANK);
 299 }
 300 EXPORT_SYMBOL_GPL(ili9320_resume);
 301 #endif
 302
 303 /* Power down all displays on reboot, poweroff or halt */
 304 void ili9320_shutdown(struct ili9320 *lcd)
 305 {
 306         ili9320_power(lcd, FB_BLANK_POWERDOWN);
 307 }
 308 EXPORT_SYMBOL_GPL(ili9320_shutdown);
 309
 310 MODULE_AUTHOR("Ben Dooks <ben-linux@fluff.org>");
 311 MODULE_DESCRIPTION("ILI9320 LCD Driver");
 312 MODULE_LICENSE("GPL v2");