1 /* 2 * l4f00242t03.c -- support for Epson L4F00242T03 LCD 3 * 4 * Copyright 2007-2009 Freescale Semiconductor, Inc. All Rights Reserved. 5 * 6 * Copyright (c) 2009 Alberto Panizzo <maramaopercheseimorto@gmail.com> 7 * Inspired by Marek Vasut work in l4f00242t03.c 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/device.h> 15 #include <linux/kernel.h> 16 #include <linux/delay.h> 17 #include <linux/module.h> 18 #include <linux/gpio.h> 19 #include <linux/lcd.h> 20 #include <linux/slab.h> 21 #include <linux/regulator/consumer.h> 22 23 #include <linux/spi/spi.h> 24 #include <linux/spi/l4f00242t03.h> 25 26 struct l4f00242t03_priv { 27 struct spi_device *spi; 28 struct lcd_device *ld; 29 int lcd_state; 30 struct regulator *io_reg; 31 struct regulator *core_reg; 32 }; 33 34 35 static void l4f00242t03_reset(unsigned int gpio) 36 { 37 pr_debug("l4f00242t03_reset.\n"); 38 gpio_set_value(gpio, 1); 39 mdelay(100); 40 gpio_set_value(gpio, 0); 41 mdelay(10); /* tRES >= 100us */ 42 gpio_set_value(gpio, 1); 43 mdelay(20); 44 } 45 46 #define param(x) ((x) | 0x100) 47 48 static void l4f00242t03_lcd_init(struct spi_device *spi) 49 { 50 struct l4f00242t03_pdata *pdata = spi->dev.platform_data; 51 struct l4f00242t03_priv *priv = dev_get_drvdata(&spi->dev); 52 const u16 cmd[] = { 0x36, param(0), 0x3A, param(0x60) }; 53 54 dev_dbg(&spi->dev, "initializing LCD\n"); 55 56 regulator_set_voltage(priv->io_reg, 1800000, 1800000); 57 regulator_enable(priv->io_reg); 58 59 regulator_set_voltage(priv->core_reg, 2800000, 2800000); 60 regulator_enable(priv->core_reg); 61 62 l4f00242t03_reset(pdata->reset_gpio); 63 64 gpio_set_value(pdata->data_enable_gpio, 1); 65 msleep(60); 66 spi_write(spi, (const u8 *)cmd, ARRAY_SIZE(cmd) * sizeof(u16)); 67 } 68 69 static void l4f00242t03_lcd_powerdown(struct spi_device *spi) 70 { 71 struct l4f00242t03_pdata *pdata = spi->dev.platform_data; 72 struct l4f00242t03_priv *priv = dev_get_drvdata(&spi->dev); 73 74 dev_dbg(&spi->dev, "Powering down LCD\n"); 75 76 gpio_set_value(pdata->data_enable_gpio, 0); 77 78 regulator_disable(priv->io_reg); 79 regulator_disable(priv->core_reg); 80 } 81 82 static int l4f00242t03_lcd_power_get(struct lcd_device *ld) 83 { 84 struct l4f00242t03_priv *priv = lcd_get_data(ld); 85 86 return priv->lcd_state; 87 } 88 89 static int l4f00242t03_lcd_power_set(struct lcd_device *ld, int power) 90 { 91 struct l4f00242t03_priv *priv = lcd_get_data(ld); 92 struct spi_device *spi = priv->spi; 93 94 const u16 slpout = 0x11; 95 const u16 dison = 0x29; 96 97 const u16 slpin = 0x10; 98 const u16 disoff = 0x28; 99 100 if (power <= FB_BLANK_NORMAL) { 101 if (priv->lcd_state <= FB_BLANK_NORMAL) { 102 /* Do nothing, the LCD is running */ 103 } else if (priv->lcd_state < FB_BLANK_POWERDOWN) { 104 dev_dbg(&spi->dev, "Resuming LCD\n"); 105 106 spi_write(spi, (const u8 *)&slpout, sizeof(u16)); 107 msleep(60); 108 spi_write(spi, (const u8 *)&dison, sizeof(u16)); 109 } else { 110 /* priv->lcd_state == FB_BLANK_POWERDOWN */ 111 l4f00242t03_lcd_init(spi); 112 priv->lcd_state = FB_BLANK_VSYNC_SUSPEND; 113 l4f00242t03_lcd_power_set(priv->ld, power); 114 } 115 } else if (power < FB_BLANK_POWERDOWN) { 116 if (priv->lcd_state <= FB_BLANK_NORMAL) { 117 /* Send the display in standby */ 118 dev_dbg(&spi->dev, "Standby the LCD\n"); 119 120 spi_write(spi, (const u8 *)&disoff, sizeof(u16)); 121 msleep(60); 122 spi_write(spi, (const u8 *)&slpin, sizeof(u16)); 123 } else if (priv->lcd_state < FB_BLANK_POWERDOWN) { 124 /* Do nothing, the LCD is already in standby */ 125 } else { 126 /* priv->lcd_state == FB_BLANK_POWERDOWN */ 127 l4f00242t03_lcd_init(spi); 128 priv->lcd_state = FB_BLANK_UNBLANK; 129 l4f00242t03_lcd_power_set(ld, power); 130 } 131 } else { 132 /* power == FB_BLANK_POWERDOWN */ 133 if (priv->lcd_state != FB_BLANK_POWERDOWN) { 134 /* Clear the screen before shutting down */ 135 spi_write(spi, (const u8 *)&disoff, sizeof(u16)); 136 msleep(60); 137 l4f00242t03_lcd_powerdown(spi); 138 } 139 } 140 141 priv->lcd_state = power; 142 143 return 0; 144 } 145 146 static struct lcd_ops l4f_ops = { 147 .set_power = l4f00242t03_lcd_power_set, 148 .get_power = l4f00242t03_lcd_power_get, 149 }; 150 151 static int __devinit l4f00242t03_probe(struct spi_device *spi) 152 { 153 struct l4f00242t03_priv *priv; 154 struct l4f00242t03_pdata *pdata = spi->dev.platform_data; 155 int ret; 156 157 if (pdata == NULL) { 158 dev_err(&spi->dev, "Uninitialized platform data.\n"); 159 return -EINVAL; 160 } 161 162 priv = kzalloc(sizeof(struct l4f00242t03_priv), GFP_KERNEL); 163 164 if (priv == NULL) { 165 dev_err(&spi->dev, "No memory for this device.\n"); 166 return -ENOMEM; 167 } 168 169 dev_set_drvdata(&spi->dev, priv); 170 spi->bits_per_word = 9; 171 spi_setup(spi); 172 173 priv->spi = spi; 174 175 ret = gpio_request_one(pdata->reset_gpio, GPIOF_OUT_INIT_HIGH, 176 "lcd l4f00242t03 reset"); 177 if (ret) { 178 dev_err(&spi->dev, 179 "Unable to get the lcd l4f00242t03 reset gpio.\n"); 180 goto err; 181 } 182 183 ret = gpio_request_one(pdata->data_enable_gpio, GPIOF_OUT_INIT_LOW, 184 "lcd l4f00242t03 data enable"); 185 if (ret) { 186 dev_err(&spi->dev, 187 "Unable to get the lcd l4f00242t03 data en gpio.\n"); 188 goto err2; 189 } 190 191 priv->io_reg = regulator_get(&spi->dev, "vdd"); 192 if (IS_ERR(priv->io_reg)) { 193 dev_err(&spi->dev, "%s: Unable to get the IO regulator\n", 194 __func__); 195 goto err3; 196 } 197 198 priv->core_reg = regulator_get(&spi->dev, "vcore"); 199 if (IS_ERR(priv->core_reg)) { 200 dev_err(&spi->dev, "%s: Unable to get the core regulator\n", 201 __func__); 202 goto err4; 203 } 204 205 priv->ld = lcd_device_register("l4f00242t03", 206 &spi->dev, priv, &l4f_ops); 207 if (IS_ERR(priv->ld)) { 208 ret = PTR_ERR(priv->ld); 209 goto err5; 210 } 211 212 /* Init the LCD */ 213 l4f00242t03_lcd_init(spi); 214 priv->lcd_state = FB_BLANK_VSYNC_SUSPEND; 215 l4f00242t03_lcd_power_set(priv->ld, FB_BLANK_UNBLANK); 216 217 dev_info(&spi->dev, "Epson l4f00242t03 lcd probed.\n"); 218 219 return 0; 220 221 err5: 222 regulator_put(priv->core_reg); 223 err4: 224 regulator_put(priv->io_reg); 225 err3: 226 gpio_free(pdata->data_enable_gpio); 227 err2: 228 gpio_free(pdata->reset_gpio); 229 err: 230 kfree(priv); 231 232 return ret; 233 } 234 235 static int __devexit l4f00242t03_remove(struct spi_device *spi) 236 { 237 struct l4f00242t03_priv *priv = dev_get_drvdata(&spi->dev); 238 struct l4f00242t03_pdata *pdata = priv->spi->dev.platform_data; 239 240 l4f00242t03_lcd_power_set(priv->ld, FB_BLANK_POWERDOWN); 241 lcd_device_unregister(priv->ld); 242 243 dev_set_drvdata(&spi->dev, NULL); 244 245 gpio_free(pdata->data_enable_gpio); 246 gpio_free(pdata->reset_gpio); 247 248 regulator_put(priv->io_reg); 249 regulator_put(priv->core_reg); 250 251 kfree(priv); 252 253 return 0; 254 } 255 256 static void l4f00242t03_shutdown(struct spi_device *spi) 257 { 258 struct l4f00242t03_priv *priv = dev_get_drvdata(&spi->dev); 259 260 if (priv) 261 l4f00242t03_lcd_power_set(priv->ld, FB_BLANK_POWERDOWN); 262 263 } 264 265 static struct spi_driver l4f00242t03_driver = { 266 .driver = { 267 .name = "l4f00242t03", 268 .owner = THIS_MODULE, 269 }, 270 .probe = l4f00242t03_probe, 271 .remove = __devexit_p(l4f00242t03_remove), 272 .shutdown = l4f00242t03_shutdown, 273 }; 274 275 static __init int l4f00242t03_init(void) 276 { 277 return spi_register_driver(&l4f00242t03_driver); 278 } 279 280 static __exit void l4f00242t03_exit(void) 281 { 282 spi_unregister_driver(&l4f00242t03_driver); 283 } 284 285 module_init(l4f00242t03_init); 286 module_exit(l4f00242t03_exit); 287 288 MODULE_AUTHOR("Alberto Panizzo <maramaopercheseimorto@gmail.com>"); 289 MODULE_DESCRIPTION("EPSON L4F00242T03 LCD"); 290 MODULE_LICENSE("GPL v2"); 291