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 dev_set_drvdata(&spi->dev, 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 274 int ili9320_suspend(struct ili9320 *lcd, pm_message_t state) 275 { 276 int ret; 277 278 dev_dbg(lcd->dev, "%s: event %d\n", __func__, state.event); 279 280 if (state.event == PM_EVENT_SUSPEND) { 281 ret = ili9320_power(lcd, FB_BLANK_POWERDOWN); 282 283 if (lcd->platdata->suspend == ILI9320_SUSPEND_DEEP) { 284 ili9320_write(lcd, ILI9320_POWER1, lcd->power1 | 285 ILI9320_POWER1_SLP | 286 ILI9320_POWER1_DSTB); 287 lcd->initialised = 0; 288 } 289 290 return ret; 291 } 292 293 return 0; 294 } 295 EXPORT_SYMBOL_GPL(ili9320_suspend); 296 297 int ili9320_resume(struct ili9320 *lcd) 298 { 299 dev_info(lcd->dev, "resuming from power state %d\n", lcd->power); 300 301 if (lcd->platdata->suspend == ILI9320_SUSPEND_DEEP) 302 ili9320_write(lcd, ILI9320_POWER1, 0x00); 303 304 return ili9320_power(lcd, FB_BLANK_UNBLANK); 305 } 306 EXPORT_SYMBOL_GPL(ili9320_resume); 307 #endif 308 309 /* Power down all displays on reboot, poweroff or halt */ 310 void ili9320_shutdown(struct ili9320 *lcd) 311 { 312 ili9320_power(lcd, FB_BLANK_POWERDOWN); 313 } 314 EXPORT_SYMBOL_GPL(ili9320_shutdown); 315 316 MODULE_AUTHOR("Ben Dooks <ben-linux@fluff.org>"); 317 MODULE_DESCRIPTION("ILI9320 LCD Driver"); 318 MODULE_LICENSE("GPL v2"); 319