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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 15 16 #include <linux/device.h> 17 #include <linux/kernel.h> 18 #include <linux/delay.h> 19 #include <linux/module.h> 20 #include <linux/gpio.h> 21 #include <linux/lcd.h> 22 #include <linux/slab.h> 23 #include <linux/regulator/consumer.h> 24 25 #include <linux/spi/spi.h> 26 #include <linux/spi/l4f00242t03.h> 27 28 struct l4f00242t03_priv { 29 struct spi_device *spi; 30 struct lcd_device *ld; 31 int lcd_state; 32 struct regulator *io_reg; 33 struct regulator *core_reg; 34 }; 35 36 static void l4f00242t03_reset(unsigned int gpio) 37 { 38 pr_debug("l4f00242t03_reset.\n"); 39 gpio_set_value(gpio, 1); 40 mdelay(100); 41 gpio_set_value(gpio, 0); 42 mdelay(10); /* tRES >= 100us */ 43 gpio_set_value(gpio, 1); 44 mdelay(20); 45 } 46 47 #define param(x) ((x) | 0x100) 48 49 static void l4f00242t03_lcd_init(struct spi_device *spi) 50 { 51 struct l4f00242t03_pdata *pdata = spi->dev.platform_data; 52 struct l4f00242t03_priv *priv = dev_get_drvdata(&spi->dev); 53 const u16 cmd[] = { 0x36, param(0), 0x3A, param(0x60) }; 54 55 dev_dbg(&spi->dev, "initializing LCD\n"); 56 57 regulator_set_voltage(priv->io_reg, 1800000, 1800000); 58 regulator_enable(priv->io_reg); 59 60 regulator_set_voltage(priv->core_reg, 2800000, 2800000); 61 regulator_enable(priv->core_reg); 62 63 l4f00242t03_reset(pdata->reset_gpio); 64 65 gpio_set_value(pdata->data_enable_gpio, 1); 66 msleep(60); 67 spi_write(spi, (const u8 *)cmd, ARRAY_SIZE(cmd) * sizeof(u16)); 68 } 69 70 static void l4f00242t03_lcd_powerdown(struct spi_device *spi) 71 { 72 struct l4f00242t03_pdata *pdata = spi->dev.platform_data; 73 struct l4f00242t03_priv *priv = dev_get_drvdata(&spi->dev); 74 75 dev_dbg(&spi->dev, "Powering down LCD\n"); 76 77 gpio_set_value(pdata->data_enable_gpio, 0); 78 79 regulator_disable(priv->io_reg); 80 regulator_disable(priv->core_reg); 81 } 82 83 static int l4f00242t03_lcd_power_get(struct lcd_device *ld) 84 { 85 struct l4f00242t03_priv *priv = lcd_get_data(ld); 86 87 return priv->lcd_state; 88 } 89 90 static int l4f00242t03_lcd_power_set(struct lcd_device *ld, int power) 91 { 92 struct l4f00242t03_priv *priv = lcd_get_data(ld); 93 struct spi_device *spi = priv->spi; 94 95 const u16 slpout = 0x11; 96 const u16 dison = 0x29; 97 98 const u16 slpin = 0x10; 99 const u16 disoff = 0x28; 100 101 if (power <= FB_BLANK_NORMAL) { 102 if (priv->lcd_state <= FB_BLANK_NORMAL) { 103 /* Do nothing, the LCD is running */ 104 } else if (priv->lcd_state < FB_BLANK_POWERDOWN) { 105 dev_dbg(&spi->dev, "Resuming LCD\n"); 106 107 spi_write(spi, (const u8 *)&slpout, sizeof(u16)); 108 msleep(60); 109 spi_write(spi, (const u8 *)&dison, sizeof(u16)); 110 } else { 111 /* priv->lcd_state == FB_BLANK_POWERDOWN */ 112 l4f00242t03_lcd_init(spi); 113 priv->lcd_state = FB_BLANK_VSYNC_SUSPEND; 114 l4f00242t03_lcd_power_set(priv->ld, power); 115 } 116 } else if (power < FB_BLANK_POWERDOWN) { 117 if (priv->lcd_state <= FB_BLANK_NORMAL) { 118 /* Send the display in standby */ 119 dev_dbg(&spi->dev, "Standby the LCD\n"); 120 121 spi_write(spi, (const u8 *)&disoff, sizeof(u16)); 122 msleep(60); 123 spi_write(spi, (const u8 *)&slpin, sizeof(u16)); 124 } else if (priv->lcd_state < FB_BLANK_POWERDOWN) { 125 /* Do nothing, the LCD is already in standby */ 126 } else { 127 /* priv->lcd_state == FB_BLANK_POWERDOWN */ 128 l4f00242t03_lcd_init(spi); 129 priv->lcd_state = FB_BLANK_UNBLANK; 130 l4f00242t03_lcd_power_set(ld, power); 131 } 132 } else { 133 /* power == FB_BLANK_POWERDOWN */ 134 if (priv->lcd_state != FB_BLANK_POWERDOWN) { 135 /* Clear the screen before shutting down */ 136 spi_write(spi, (const u8 *)&disoff, sizeof(u16)); 137 msleep(60); 138 l4f00242t03_lcd_powerdown(spi); 139 } 140 } 141 142 priv->lcd_state = power; 143 144 return 0; 145 } 146 147 static struct lcd_ops l4f_ops = { 148 .set_power = l4f00242t03_lcd_power_set, 149 .get_power = l4f00242t03_lcd_power_get, 150 }; 151 152 static int l4f00242t03_probe(struct spi_device *spi) 153 { 154 struct l4f00242t03_priv *priv; 155 struct l4f00242t03_pdata *pdata = spi->dev.platform_data; 156 int ret; 157 158 if (pdata == NULL) { 159 dev_err(&spi->dev, "Uninitialized platform data.\n"); 160 return -EINVAL; 161 } 162 163 priv = devm_kzalloc(&spi->dev, sizeof(struct l4f00242t03_priv), 164 GFP_KERNEL); 165 166 if (priv == NULL) { 167 dev_err(&spi->dev, "No memory for this device.\n"); 168 return -ENOMEM; 169 } 170 171 dev_set_drvdata(&spi->dev, priv); 172 spi->bits_per_word = 9; 173 spi_setup(spi); 174 175 priv->spi = spi; 176 177 ret = devm_gpio_request_one(&spi->dev, pdata->reset_gpio, 178 GPIOF_OUT_INIT_HIGH, "lcd l4f00242t03 reset"); 179 if (ret) { 180 dev_err(&spi->dev, 181 "Unable to get the lcd l4f00242t03 reset gpio.\n"); 182 return ret; 183 } 184 185 ret = devm_gpio_request_one(&spi->dev, pdata->data_enable_gpio, 186 GPIOF_OUT_INIT_LOW, "lcd l4f00242t03 data enable"); 187 if (ret) { 188 dev_err(&spi->dev, 189 "Unable to get the lcd l4f00242t03 data en gpio.\n"); 190 return ret; 191 } 192 193 priv->io_reg = regulator_get(&spi->dev, "vdd"); 194 if (IS_ERR(priv->io_reg)) { 195 dev_err(&spi->dev, "%s: Unable to get the IO regulator\n", 196 __func__); 197 return PTR_ERR(priv->io_reg); 198 } 199 200 priv->core_reg = regulator_get(&spi->dev, "vcore"); 201 if (IS_ERR(priv->core_reg)) { 202 ret = PTR_ERR(priv->core_reg); 203 dev_err(&spi->dev, "%s: Unable to get the core regulator\n", 204 __func__); 205 goto err1; 206 } 207 208 priv->ld = lcd_device_register("l4f00242t03", 209 &spi->dev, priv, &l4f_ops); 210 if (IS_ERR(priv->ld)) { 211 ret = PTR_ERR(priv->ld); 212 goto err2; 213 } 214 215 /* Init the LCD */ 216 l4f00242t03_lcd_init(spi); 217 priv->lcd_state = FB_BLANK_VSYNC_SUSPEND; 218 l4f00242t03_lcd_power_set(priv->ld, FB_BLANK_UNBLANK); 219 220 dev_info(&spi->dev, "Epson l4f00242t03 lcd probed.\n"); 221 222 return 0; 223 224 err2: 225 regulator_put(priv->core_reg); 226 err1: 227 regulator_put(priv->io_reg); 228 229 return ret; 230 } 231 232 static int l4f00242t03_remove(struct spi_device *spi) 233 { 234 struct l4f00242t03_priv *priv = dev_get_drvdata(&spi->dev); 235 236 l4f00242t03_lcd_power_set(priv->ld, FB_BLANK_POWERDOWN); 237 lcd_device_unregister(priv->ld); 238 239 dev_set_drvdata(&spi->dev, NULL); 240 241 regulator_put(priv->io_reg); 242 regulator_put(priv->core_reg); 243 244 return 0; 245 } 246 247 static void l4f00242t03_shutdown(struct spi_device *spi) 248 { 249 struct l4f00242t03_priv *priv = dev_get_drvdata(&spi->dev); 250 251 if (priv) 252 l4f00242t03_lcd_power_set(priv->ld, FB_BLANK_POWERDOWN); 253 254 } 255 256 static struct spi_driver l4f00242t03_driver = { 257 .driver = { 258 .name = "l4f00242t03", 259 .owner = THIS_MODULE, 260 }, 261 .probe = l4f00242t03_probe, 262 .remove = l4f00242t03_remove, 263 .shutdown = l4f00242t03_shutdown, 264 }; 265 266 module_spi_driver(l4f00242t03_driver); 267 268 MODULE_AUTHOR("Alberto Panizzo <maramaopercheseimorto@gmail.com>"); 269 MODULE_DESCRIPTION("EPSON L4F00242T03 LCD"); 270 MODULE_LICENSE("GPL v2"); 271