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 = dev_get_platdata(&spi->dev); 52 struct l4f00242t03_priv *priv = spi_get_drvdata(spi); 53 const u16 cmd[] = { 0x36, param(0), 0x3A, param(0x60) }; 54 int ret; 55 56 dev_dbg(&spi->dev, "initializing LCD\n"); 57 58 ret = regulator_set_voltage(priv->io_reg, 1800000, 1800000); 59 if (ret) { 60 dev_err(&spi->dev, "failed to set the IO regulator voltage.\n"); 61 return; 62 } 63 ret = regulator_enable(priv->io_reg); 64 if (ret) { 65 dev_err(&spi->dev, "failed to enable the IO regulator.\n"); 66 return; 67 } 68 69 ret = regulator_set_voltage(priv->core_reg, 2800000, 2800000); 70 if (ret) { 71 dev_err(&spi->dev, "failed to set the core regulator voltage.\n"); 72 regulator_disable(priv->io_reg); 73 return; 74 } 75 ret = regulator_enable(priv->core_reg); 76 if (ret) { 77 dev_err(&spi->dev, "failed to enable the core regulator.\n"); 78 regulator_disable(priv->io_reg); 79 return; 80 } 81 82 l4f00242t03_reset(pdata->reset_gpio); 83 84 gpio_set_value(pdata->data_enable_gpio, 1); 85 msleep(60); 86 spi_write(spi, (const u8 *)cmd, ARRAY_SIZE(cmd) * sizeof(u16)); 87 } 88 89 static void l4f00242t03_lcd_powerdown(struct spi_device *spi) 90 { 91 struct l4f00242t03_pdata *pdata = dev_get_platdata(&spi->dev); 92 struct l4f00242t03_priv *priv = spi_get_drvdata(spi); 93 94 dev_dbg(&spi->dev, "Powering down LCD\n"); 95 96 gpio_set_value(pdata->data_enable_gpio, 0); 97 98 regulator_disable(priv->io_reg); 99 regulator_disable(priv->core_reg); 100 } 101 102 static int l4f00242t03_lcd_power_get(struct lcd_device *ld) 103 { 104 struct l4f00242t03_priv *priv = lcd_get_data(ld); 105 106 return priv->lcd_state; 107 } 108 109 static int l4f00242t03_lcd_power_set(struct lcd_device *ld, int power) 110 { 111 struct l4f00242t03_priv *priv = lcd_get_data(ld); 112 struct spi_device *spi = priv->spi; 113 114 const u16 slpout = 0x11; 115 const u16 dison = 0x29; 116 117 const u16 slpin = 0x10; 118 const u16 disoff = 0x28; 119 120 if (power <= FB_BLANK_NORMAL) { 121 if (priv->lcd_state <= FB_BLANK_NORMAL) { 122 /* Do nothing, the LCD is running */ 123 } else if (priv->lcd_state < FB_BLANK_POWERDOWN) { 124 dev_dbg(&spi->dev, "Resuming LCD\n"); 125 126 spi_write(spi, (const u8 *)&slpout, sizeof(u16)); 127 msleep(60); 128 spi_write(spi, (const u8 *)&dison, sizeof(u16)); 129 } else { 130 /* priv->lcd_state == FB_BLANK_POWERDOWN */ 131 l4f00242t03_lcd_init(spi); 132 priv->lcd_state = FB_BLANK_VSYNC_SUSPEND; 133 l4f00242t03_lcd_power_set(priv->ld, power); 134 } 135 } else if (power < FB_BLANK_POWERDOWN) { 136 if (priv->lcd_state <= FB_BLANK_NORMAL) { 137 /* Send the display in standby */ 138 dev_dbg(&spi->dev, "Standby the LCD\n"); 139 140 spi_write(spi, (const u8 *)&disoff, sizeof(u16)); 141 msleep(60); 142 spi_write(spi, (const u8 *)&slpin, sizeof(u16)); 143 } else if (priv->lcd_state < FB_BLANK_POWERDOWN) { 144 /* Do nothing, the LCD is already in standby */ 145 } else { 146 /* priv->lcd_state == FB_BLANK_POWERDOWN */ 147 l4f00242t03_lcd_init(spi); 148 priv->lcd_state = FB_BLANK_UNBLANK; 149 l4f00242t03_lcd_power_set(ld, power); 150 } 151 } else { 152 /* power == FB_BLANK_POWERDOWN */ 153 if (priv->lcd_state != FB_BLANK_POWERDOWN) { 154 /* Clear the screen before shutting down */ 155 spi_write(spi, (const u8 *)&disoff, sizeof(u16)); 156 msleep(60); 157 l4f00242t03_lcd_powerdown(spi); 158 } 159 } 160 161 priv->lcd_state = power; 162 163 return 0; 164 } 165 166 static struct lcd_ops l4f_ops = { 167 .set_power = l4f00242t03_lcd_power_set, 168 .get_power = l4f00242t03_lcd_power_get, 169 }; 170 171 static int l4f00242t03_probe(struct spi_device *spi) 172 { 173 struct l4f00242t03_priv *priv; 174 struct l4f00242t03_pdata *pdata = dev_get_platdata(&spi->dev); 175 int ret; 176 177 if (pdata == NULL) { 178 dev_err(&spi->dev, "Uninitialized platform data.\n"); 179 return -EINVAL; 180 } 181 182 priv = devm_kzalloc(&spi->dev, sizeof(struct l4f00242t03_priv), 183 GFP_KERNEL); 184 if (priv == NULL) 185 return -ENOMEM; 186 187 spi_set_drvdata(spi, priv); 188 spi->bits_per_word = 9; 189 spi_setup(spi); 190 191 priv->spi = spi; 192 193 ret = devm_gpio_request_one(&spi->dev, pdata->reset_gpio, 194 GPIOF_OUT_INIT_HIGH, "lcd l4f00242t03 reset"); 195 if (ret) { 196 dev_err(&spi->dev, 197 "Unable to get the lcd l4f00242t03 reset gpio.\n"); 198 return ret; 199 } 200 201 ret = devm_gpio_request_one(&spi->dev, pdata->data_enable_gpio, 202 GPIOF_OUT_INIT_LOW, "lcd l4f00242t03 data enable"); 203 if (ret) { 204 dev_err(&spi->dev, 205 "Unable to get the lcd l4f00242t03 data en gpio.\n"); 206 return ret; 207 } 208 209 priv->io_reg = devm_regulator_get(&spi->dev, "vdd"); 210 if (IS_ERR(priv->io_reg)) { 211 dev_err(&spi->dev, "%s: Unable to get the IO regulator\n", 212 __func__); 213 return PTR_ERR(priv->io_reg); 214 } 215 216 priv->core_reg = devm_regulator_get(&spi->dev, "vcore"); 217 if (IS_ERR(priv->core_reg)) { 218 dev_err(&spi->dev, "%s: Unable to get the core regulator\n", 219 __func__); 220 return PTR_ERR(priv->core_reg); 221 } 222 223 priv->ld = devm_lcd_device_register(&spi->dev, "l4f00242t03", &spi->dev, 224 priv, &l4f_ops); 225 if (IS_ERR(priv->ld)) 226 return PTR_ERR(priv->ld); 227 228 /* Init the LCD */ 229 l4f00242t03_lcd_init(spi); 230 priv->lcd_state = FB_BLANK_VSYNC_SUSPEND; 231 l4f00242t03_lcd_power_set(priv->ld, FB_BLANK_UNBLANK); 232 233 dev_info(&spi->dev, "Epson l4f00242t03 lcd probed.\n"); 234 235 return 0; 236 } 237 238 static int l4f00242t03_remove(struct spi_device *spi) 239 { 240 struct l4f00242t03_priv *priv = spi_get_drvdata(spi); 241 242 l4f00242t03_lcd_power_set(priv->ld, FB_BLANK_POWERDOWN); 243 return 0; 244 } 245 246 static void l4f00242t03_shutdown(struct spi_device *spi) 247 { 248 struct l4f00242t03_priv *priv = spi_get_drvdata(spi); 249 250 if (priv) 251 l4f00242t03_lcd_power_set(priv->ld, FB_BLANK_POWERDOWN); 252 253 } 254 255 static struct spi_driver l4f00242t03_driver = { 256 .driver = { 257 .name = "l4f00242t03", 258 .owner = THIS_MODULE, 259 }, 260 .probe = l4f00242t03_probe, 261 .remove = l4f00242t03_remove, 262 .shutdown = l4f00242t03_shutdown, 263 }; 264 265 module_spi_driver(l4f00242t03_driver); 266 267 MODULE_AUTHOR("Alberto Panizzo <maramaopercheseimorto@gmail.com>"); 268 MODULE_DESCRIPTION("EPSON L4F00242T03 LCD"); 269 MODULE_LICENSE("GPL v2"); 270