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 const 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 void ili9320_remove(struct ili9320 *ili) 255 { 256 ili9320_power(ili, FB_BLANK_POWERDOWN); 257 } 258 EXPORT_SYMBOL_GPL(ili9320_remove); 259 260 #ifdef CONFIG_PM_SLEEP 261 int ili9320_suspend(struct ili9320 *lcd) 262 { 263 int ret; 264 265 ret = ili9320_power(lcd, FB_BLANK_POWERDOWN); 266 267 if (lcd->platdata->suspend == ILI9320_SUSPEND_DEEP) { 268 ili9320_write(lcd, ILI9320_POWER1, lcd->power1 | 269 ILI9320_POWER1_SLP | 270 ILI9320_POWER1_DSTB); 271 lcd->initialised = 0; 272 } 273 274 return ret; 275 } 276 EXPORT_SYMBOL_GPL(ili9320_suspend); 277 278 int ili9320_resume(struct ili9320 *lcd) 279 { 280 dev_info(lcd->dev, "resuming from power state %d\n", lcd->power); 281 282 if (lcd->platdata->suspend == ILI9320_SUSPEND_DEEP) 283 ili9320_write(lcd, ILI9320_POWER1, 0x00); 284 285 return ili9320_power(lcd, FB_BLANK_UNBLANK); 286 } 287 EXPORT_SYMBOL_GPL(ili9320_resume); 288 #endif 289 290 /* Power down all displays on reboot, poweroff or halt */ 291 void ili9320_shutdown(struct ili9320 *lcd) 292 { 293 ili9320_power(lcd, FB_BLANK_POWERDOWN); 294 } 295 EXPORT_SYMBOL_GPL(ili9320_shutdown); 296 297 MODULE_AUTHOR("Ben Dooks <ben-linux@fluff.org>"); 298 MODULE_DESCRIPTION("ILI9320 LCD Driver"); 299 MODULE_LICENSE("GPL v2"); 300