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 37 static void l4f00242t03_reset(unsigned int gpio) 38 { 39 pr_debug("l4f00242t03_reset.\n"); 40 gpio_set_value(gpio, 1); 41 mdelay(100); 42 gpio_set_value(gpio, 0); 43 mdelay(10); /* tRES >= 100us */ 44 gpio_set_value(gpio, 1); 45 mdelay(20); 46 } 47 48 #define param(x) ((x) | 0x100) 49 50 static void l4f00242t03_lcd_init(struct spi_device *spi) 51 { 52 struct l4f00242t03_pdata *pdata = spi->dev.platform_data; 53 struct l4f00242t03_priv *priv = dev_get_drvdata(&spi->dev); 54 const u16 cmd[] = { 0x36, param(0), 0x3A, param(0x60) }; 55 56 dev_dbg(&spi->dev, "initializing LCD\n"); 57 58 regulator_set_voltage(priv->io_reg, 1800000, 1800000); 59 regulator_enable(priv->io_reg); 60 61 regulator_set_voltage(priv->core_reg, 2800000, 2800000); 62 regulator_enable(priv->core_reg); 63 64 l4f00242t03_reset(pdata->reset_gpio); 65 66 gpio_set_value(pdata->data_enable_gpio, 1); 67 msleep(60); 68 spi_write(spi, (const u8 *)cmd, ARRAY_SIZE(cmd) * sizeof(u16)); 69 } 70 71 static void l4f00242t03_lcd_powerdown(struct spi_device *spi) 72 { 73 struct l4f00242t03_pdata *pdata = spi->dev.platform_data; 74 struct l4f00242t03_priv *priv = dev_get_drvdata(&spi->dev); 75 76 dev_dbg(&spi->dev, "Powering down LCD\n"); 77 78 gpio_set_value(pdata->data_enable_gpio, 0); 79 80 regulator_disable(priv->io_reg); 81 regulator_disable(priv->core_reg); 82 } 83 84 static int l4f00242t03_lcd_power_get(struct lcd_device *ld) 85 { 86 struct l4f00242t03_priv *priv = lcd_get_data(ld); 87 88 return priv->lcd_state; 89 } 90 91 static int l4f00242t03_lcd_power_set(struct lcd_device *ld, int power) 92 { 93 struct l4f00242t03_priv *priv = lcd_get_data(ld); 94 struct spi_device *spi = priv->spi; 95 96 const u16 slpout = 0x11; 97 const u16 dison = 0x29; 98 99 const u16 slpin = 0x10; 100 const u16 disoff = 0x28; 101 102 if (power <= FB_BLANK_NORMAL) { 103 if (priv->lcd_state <= FB_BLANK_NORMAL) { 104 /* Do nothing, the LCD is running */ 105 } else if (priv->lcd_state < FB_BLANK_POWERDOWN) { 106 dev_dbg(&spi->dev, "Resuming LCD\n"); 107 108 spi_write(spi, (const u8 *)&slpout, sizeof(u16)); 109 msleep(60); 110 spi_write(spi, (const u8 *)&dison, sizeof(u16)); 111 } else { 112 /* priv->lcd_state == FB_BLANK_POWERDOWN */ 113 l4f00242t03_lcd_init(spi); 114 priv->lcd_state = FB_BLANK_VSYNC_SUSPEND; 115 l4f00242t03_lcd_power_set(priv->ld, power); 116 } 117 } else if (power < FB_BLANK_POWERDOWN) { 118 if (priv->lcd_state <= FB_BLANK_NORMAL) { 119 /* Send the display in standby */ 120 dev_dbg(&spi->dev, "Standby the LCD\n"); 121 122 spi_write(spi, (const u8 *)&disoff, sizeof(u16)); 123 msleep(60); 124 spi_write(spi, (const u8 *)&slpin, sizeof(u16)); 125 } else if (priv->lcd_state < FB_BLANK_POWERDOWN) { 126 /* Do nothing, the LCD is already in standby */ 127 } else { 128 /* priv->lcd_state == FB_BLANK_POWERDOWN */ 129 l4f00242t03_lcd_init(spi); 130 priv->lcd_state = FB_BLANK_UNBLANK; 131 l4f00242t03_lcd_power_set(ld, power); 132 } 133 } else { 134 /* power == FB_BLANK_POWERDOWN */ 135 if (priv->lcd_state != FB_BLANK_POWERDOWN) { 136 /* Clear the screen before shutting down */ 137 spi_write(spi, (const u8 *)&disoff, sizeof(u16)); 138 msleep(60); 139 l4f00242t03_lcd_powerdown(spi); 140 } 141 } 142 143 priv->lcd_state = power; 144 145 return 0; 146 } 147 148 static struct lcd_ops l4f_ops = { 149 .set_power = l4f00242t03_lcd_power_set, 150 .get_power = l4f00242t03_lcd_power_get, 151 }; 152 153 static int l4f00242t03_probe(struct spi_device *spi) 154 { 155 struct l4f00242t03_priv *priv; 156 struct l4f00242t03_pdata *pdata = spi->dev.platform_data; 157 int ret; 158 159 if (pdata == NULL) { 160 dev_err(&spi->dev, "Uninitialized platform data.\n"); 161 return -EINVAL; 162 } 163 164 priv = devm_kzalloc(&spi->dev, sizeof(struct l4f00242t03_priv), 165 GFP_KERNEL); 166 167 if (priv == NULL) { 168 dev_err(&spi->dev, "No memory for this device.\n"); 169 return -ENOMEM; 170 } 171 172 dev_set_drvdata(&spi->dev, priv); 173 spi->bits_per_word = 9; 174 spi_setup(spi); 175 176 priv->spi = spi; 177 178 ret = devm_gpio_request_one(&spi->dev, pdata->reset_gpio, 179 GPIOF_OUT_INIT_HIGH, "lcd l4f00242t03 reset"); 180 if (ret) { 181 dev_err(&spi->dev, 182 "Unable to get the lcd l4f00242t03 reset gpio.\n"); 183 return ret; 184 } 185 186 ret = devm_gpio_request_one(&spi->dev, pdata->data_enable_gpio, 187 GPIOF_OUT_INIT_LOW, "lcd l4f00242t03 data enable"); 188 if (ret) { 189 dev_err(&spi->dev, 190 "Unable to get the lcd l4f00242t03 data en gpio.\n"); 191 return ret; 192 } 193 194 priv->io_reg = regulator_get(&spi->dev, "vdd"); 195 if (IS_ERR(priv->io_reg)) { 196 dev_err(&spi->dev, "%s: Unable to get the IO regulator\n", 197 __func__); 198 return PTR_ERR(priv->io_reg); 199 } 200 201 priv->core_reg = regulator_get(&spi->dev, "vcore"); 202 if (IS_ERR(priv->core_reg)) { 203 ret = PTR_ERR(priv->core_reg); 204 dev_err(&spi->dev, "%s: Unable to get the core regulator\n", 205 __func__); 206 goto err1; 207 } 208 209 priv->ld = lcd_device_register("l4f00242t03", 210 &spi->dev, priv, &l4f_ops); 211 if (IS_ERR(priv->ld)) { 212 ret = PTR_ERR(priv->ld); 213 goto err2; 214 } 215 216 /* Init the LCD */ 217 l4f00242t03_lcd_init(spi); 218 priv->lcd_state = FB_BLANK_VSYNC_SUSPEND; 219 l4f00242t03_lcd_power_set(priv->ld, FB_BLANK_UNBLANK); 220 221 dev_info(&spi->dev, "Epson l4f00242t03 lcd probed.\n"); 222 223 return 0; 224 225 err2: 226 regulator_put(priv->core_reg); 227 err1: 228 regulator_put(priv->io_reg); 229 230 return ret; 231 } 232 233 static int l4f00242t03_remove(struct spi_device *spi) 234 { 235 struct l4f00242t03_priv *priv = dev_get_drvdata(&spi->dev); 236 237 l4f00242t03_lcd_power_set(priv->ld, FB_BLANK_POWERDOWN); 238 lcd_device_unregister(priv->ld); 239 240 dev_set_drvdata(&spi->dev, NULL); 241 242 regulator_put(priv->io_reg); 243 regulator_put(priv->core_reg); 244 245 return 0; 246 } 247 248 static void l4f00242t03_shutdown(struct spi_device *spi) 249 { 250 struct l4f00242t03_priv *priv = dev_get_drvdata(&spi->dev); 251 252 if (priv) 253 l4f00242t03_lcd_power_set(priv->ld, FB_BLANK_POWERDOWN); 254 255 } 256 257 static struct spi_driver l4f00242t03_driver = { 258 .driver = { 259 .name = "l4f00242t03", 260 .owner = THIS_MODULE, 261 }, 262 .probe = l4f00242t03_probe, 263 .remove = l4f00242t03_remove, 264 .shutdown = l4f00242t03_shutdown, 265 }; 266 267 module_spi_driver(l4f00242t03_driver); 268 269 MODULE_AUTHOR("Alberto Panizzo <maramaopercheseimorto@gmail.com>"); 270 MODULE_DESCRIPTION("EPSON L4F00242T03 LCD"); 271 MODULE_LICENSE("GPL v2"); 272