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