drivers/video/backlight/ili9320.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /* drivers/video/backlight/ili9320.c
   3  *
   4  * ILI9320 LCD controller driver core.
   5  *
   6  * Copyright 2007 Simtec Electronics
   7  *      http://armlinux.simtec.co.uk/
   8  *      Ben Dooks <ben@simtec.co.uk>
   9 */
  10
  11 #include <linux/delay.h>
  12 #include <linux/err.h>
  13 #include <linux/fb.h>
  14 #include <linux/init.h>
  15 #include <linux/lcd.h>
  16 #include <linux/module.h>
  17 #include <linux/slab.h>
  18
  19 #include <linux/spi/spi.h>
  20
  21 #include <video/ili9320.h>
  22
  23 #include "ili9320.h"
  24
  25
  26 static inline int ili9320_write_spi(struct ili9320 *ili,
  27                                     unsigned int reg,
  28                                     unsigned int value)
  29 {
  30         struct ili9320_spi *spi = &ili->access.spi;
  31         unsigned char *addr = spi->buffer_addr;
  32         unsigned char *data = spi->buffer_data;
  33
  34         /* spi message consits of:
  35          * first byte: ID and operation
  36          */
  37
  38         addr[0] = spi->id | ILI9320_SPI_INDEX | ILI9320_SPI_WRITE;
  39         addr[1] = reg >> 8;
  40         addr[2] = reg;
  41
  42         /* second message is the data to transfer */
  43
  44         data[0] = spi->id | ILI9320_SPI_DATA  | ILI9320_SPI_WRITE;
  45         data[1] = value >> 8;
  46         data[2] = value;
  47
  48         return spi_sync(spi->dev, &spi->message);
  49 }
  50
  51 int ili9320_write(struct ili9320 *ili, unsigned int reg, unsigned int value)
  52 {
  53         dev_dbg(ili->dev, "write: reg=%02x, val=%04x\n", reg, value);
  54         return ili->write(ili, reg, value);
  55 }
  56 EXPORT_SYMBOL_GPL(ili9320_write);
  57
  58 int ili9320_write_regs(struct ili9320 *ili,
  59                        const struct ili9320_reg *values,
  60                        int nr_values)
  61 {
  62         int index;
  63         int ret;
  64
  65         for (index = 0; index < nr_values; index++, values++) {
  66                 ret = ili9320_write(ili, values->address, values->value);
  67                 if (ret != 0)
  68                         return ret;
  69         }
  70
  71         return 0;
  72 }
  73 EXPORT_SYMBOL_GPL(ili9320_write_regs);
  74
  75 static void ili9320_reset(struct ili9320 *lcd)
  76 {
  77         struct ili9320_platdata *cfg = lcd->platdata;
  78
  79         cfg->reset(1);
  80         mdelay(50);
  81
  82         cfg->reset(0);
  83         mdelay(50);
  84
  85         cfg->reset(1);
  86         mdelay(100);
  87 }
  88
  89 static inline int ili9320_init_chip(struct ili9320 *lcd)
  90 {
  91         int ret;
  92
  93         ili9320_reset(lcd);
  94
  95         ret = lcd->client->init(lcd, lcd->platdata);
  96         if (ret != 0) {
  97                 dev_err(lcd->dev, "failed to initialise display\n");
  98                 return ret;
  99         }
 100
 101         lcd->initialised = 1;
 102         return 0;
 103 }
 104
 105 static inline int ili9320_power_on(struct ili9320 *lcd)
 106 {
 107         if (!lcd->initialised)
 108                 ili9320_init_chip(lcd);
 109
 110         lcd->display1 |= (ILI9320_DISPLAY1_D(3) | ILI9320_DISPLAY1_BASEE);
 111         ili9320_write(lcd, ILI9320_DISPLAY1, lcd->display1);
 112
 113         return 0;
 114 }
 115
 116 static inline int ili9320_power_off(struct ili9320 *lcd)
 117 {
 118         lcd->display1 &= ~(ILI9320_DISPLAY1_D(3) | ILI9320_DISPLAY1_BASEE);
 119         ili9320_write(lcd, ILI9320_DISPLAY1, lcd->display1);
 120
 121         return 0;
 122 }
 123
 124 #define POWER_IS_ON(pwr)        ((pwr) <= FB_BLANK_NORMAL)
 125
 126 static int ili9320_power(struct ili9320 *lcd, int power)
 127 {
 128         int ret = 0;
 129
 130         dev_dbg(lcd->dev, "power %d => %d\n", lcd->power, power);
 131
 132         if (POWER_IS_ON(power) && !POWER_IS_ON(lcd->power))
 133                 ret = ili9320_power_on(lcd);
 134         else if (!POWER_IS_ON(power) && POWER_IS_ON(lcd->power))
 135                 ret = ili9320_power_off(lcd);
 136
 137         if (ret == 0)
 138                 lcd->power = power;
 139         else
 140                 dev_warn(lcd->dev, "failed to set power mode %d\n", power);
 141
 142         return ret;
 143 }
 144
 145 static inline struct ili9320 *to_our_lcd(struct lcd_device *lcd)
 146 {
 147         return lcd_get_data(lcd);
 148 }
 149
 150 static int ili9320_set_power(struct lcd_device *ld, int power)
 151 {
 152         struct ili9320 *lcd = to_our_lcd(ld);
 153
 154         return ili9320_power(lcd, power);
 155 }
 156
 157 static int ili9320_get_power(struct lcd_device *ld)
 158 {
 159         struct ili9320 *lcd = to_our_lcd(ld);
 160
 161         return lcd->power;
 162 }
 163
 164 static struct lcd_ops ili9320_ops = {
 165         .get_power      = ili9320_get_power,
 166         .set_power      = ili9320_set_power,
 167 };
 168
 169 static void ili9320_setup_spi(struct ili9320 *ili,
 170                                         struct spi_device *dev)
 171 {
 172         struct ili9320_spi *spi = &ili->access.spi;
 173
 174         ili->write = ili9320_write_spi;
 175         spi->dev = dev;
 176
 177         /* fill the two messages we are going to use to send the data
 178          * with, the first the address followed by the data. The datasheet
 179          * says they should be done as two distinct cycles of the SPI CS line.
 180          */
 181
 182         spi->xfer[0].tx_buf = spi->buffer_addr;
 183         spi->xfer[1].tx_buf = spi->buffer_data;
 184         spi->xfer[0].len = 3;
 185         spi->xfer[1].len = 3;
 186         spi->xfer[0].bits_per_word = 8;
 187         spi->xfer[1].bits_per_word = 8;
 188         spi->xfer[0].cs_change = 1;
 189
 190         spi_message_init(&spi->message);
 191         spi_message_add_tail(&spi->xfer[0], &spi->message);
 192         spi_message_add_tail(&spi->xfer[1], &spi->message);
 193 }
 194
 195 int ili9320_probe_spi(struct spi_device *spi,
 196                                 struct ili9320_client *client)
 197 {
 198         struct ili9320_platdata *cfg = dev_get_platdata(&spi->dev);
 199         struct device *dev = &spi->dev;
 200         struct ili9320 *ili;
 201         struct lcd_device *lcd;
 202         int ret = 0;
 203
 204         /* verify we where given some information */
 205
 206         if (cfg == NULL) {
 207                 dev_err(dev, "no platform data supplied\n");
 208                 return -EINVAL;
 209         }
 210
 211         if (cfg->hsize <= 0 || cfg->vsize <= 0 || cfg->reset == NULL) {
 212                 dev_err(dev, "invalid platform data supplied\n");
 213                 return -EINVAL;
 214         }
 215
 216         /* allocate and initialse our state */
 217
 218         ili = devm_kzalloc(&spi->dev, sizeof(struct ili9320), GFP_KERNEL);
 219         if (ili == NULL)
 220                 return -ENOMEM;
 221
 222         ili->access.spi.id = ILI9320_SPI_IDCODE | ILI9320_SPI_ID(1);
 223
 224         ili->dev = dev;
 225         ili->client = client;
 226         ili->power = FB_BLANK_POWERDOWN;
 227         ili->platdata = cfg;
 228
 229         spi_set_drvdata(spi, ili);
 230
 231         ili9320_setup_spi(ili, spi);
 232
 233         lcd = devm_lcd_device_register(&spi->dev, "ili9320", dev, ili,
 234                                         &ili9320_ops);
 235         if (IS_ERR(lcd)) {
 236                 dev_err(dev, "failed to register lcd device\n");
 237                 return PTR_ERR(lcd);
 238         }
 239
 240         ili->lcd = lcd;
 241
 242         dev_info(dev, "initialising %s\n", client->name);
 243
 244         ret = ili9320_power(ili, FB_BLANK_UNBLANK);
 245         if (ret != 0) {
 246                 dev_err(dev, "failed to set lcd power state\n");
 247                 return ret;
 248         }
 249
 250         return 0;
 251 }
 252 EXPORT_SYMBOL_GPL(ili9320_probe_spi);
 253
 254 int ili9320_remove(struct ili9320 *ili)
 255 {
 256         ili9320_power(ili, FB_BLANK_POWERDOWN);
 257         return 0;
 258 }
 259 EXPORT_SYMBOL_GPL(ili9320_remove);
 260
 261 #ifdef CONFIG_PM_SLEEP
 262 int ili9320_suspend(struct ili9320 *lcd)
 263 {
 264         int ret;
 265
 266         ret = ili9320_power(lcd, FB_BLANK_POWERDOWN);
 267
 268         if (lcd->platdata->suspend == ILI9320_SUSPEND_DEEP) {
 269                 ili9320_write(lcd, ILI9320_POWER1, lcd->power1 |
 270                               ILI9320_POWER1_SLP |
 271                               ILI9320_POWER1_DSTB);
 272                 lcd->initialised = 0;
 273         }
 274
 275         return ret;
 276 }
 277 EXPORT_SYMBOL_GPL(ili9320_suspend);
 278
 279 int ili9320_resume(struct ili9320 *lcd)
 280 {
 281         dev_info(lcd->dev, "resuming from power state %d\n", lcd->power);
 282
 283         if (lcd->platdata->suspend == ILI9320_SUSPEND_DEEP)
 284                 ili9320_write(lcd, ILI9320_POWER1, 0x00);
 285
 286         return ili9320_power(lcd, FB_BLANK_UNBLANK);
 287 }
 288 EXPORT_SYMBOL_GPL(ili9320_resume);
 289 #endif
 290
 291 /* Power down all displays on reboot, poweroff or halt */
 292 void ili9320_shutdown(struct ili9320 *lcd)
 293 {
 294         ili9320_power(lcd, FB_BLANK_POWERDOWN);
 295 }
 296 EXPORT_SYMBOL_GPL(ili9320_shutdown);
 297
 298 MODULE_AUTHOR("Ben Dooks <ben-linux@fluff.org>");
 299 MODULE_DESCRIPTION("ILI9320 LCD Driver");
 300 MODULE_LICENSE("GPL v2");