1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * l4f00242t03.c -- support for Epson L4F00242T03 LCD 4 * 5 * Copyright 2007-2009 Freescale Semiconductor, Inc. All Rights Reserved. 6 * 7 * Copyright (c) 2009 Alberto Panizzo <maramaopercheseimorto@gmail.com> 8 * Inspired by Marek Vasut work in l4f00242t03.c 9 */ 10 11 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 12 13 #include <linux/device.h> 14 #include <linux/kernel.h> 15 #include <linux/delay.h> 16 #include <linux/module.h> 17 #include <linux/gpio/consumer.h> 18 #include <linux/lcd.h> 19 #include <linux/slab.h> 20 #include <linux/regulator/consumer.h> 21 #include <linux/spi/spi.h> 22 23 struct l4f00242t03_priv { 24 struct spi_device *spi; 25 struct lcd_device *ld; 26 int lcd_state; 27 struct regulator *io_reg; 28 struct regulator *core_reg; 29 struct gpio_desc *reset; 30 struct gpio_desc *enable; 31 }; 32 33 static void l4f00242t03_reset(struct gpio_desc *gpiod) 34 { 35 pr_debug("l4f00242t03_reset.\n"); 36 gpiod_set_value(gpiod, 1); 37 mdelay(100); 38 gpiod_set_value(gpiod, 0); 39 mdelay(10); /* tRES >= 100us */ 40 gpiod_set_value(gpiod, 1); 41 mdelay(20); 42 } 43 44 #define param(x) ((x) | 0x100) 45 46 static void l4f00242t03_lcd_init(struct spi_device *spi) 47 { 48 struct l4f00242t03_priv *priv = spi_get_drvdata(spi); 49 const u16 cmd[] = { 0x36, param(0), 0x3A, param(0x60) }; 50 int ret; 51 52 dev_dbg(&spi->dev, "initializing LCD\n"); 53 54 ret = regulator_set_voltage(priv->io_reg, 1800000, 1800000); 55 if (ret) { 56 dev_err(&spi->dev, "failed to set the IO regulator voltage.\n"); 57 return; 58 } 59 ret = regulator_enable(priv->io_reg); 60 if (ret) { 61 dev_err(&spi->dev, "failed to enable the IO regulator.\n"); 62 return; 63 } 64 65 ret = regulator_set_voltage(priv->core_reg, 2800000, 2800000); 66 if (ret) { 67 dev_err(&spi->dev, "failed to set the core regulator voltage.\n"); 68 regulator_disable(priv->io_reg); 69 return; 70 } 71 ret = regulator_enable(priv->core_reg); 72 if (ret) { 73 dev_err(&spi->dev, "failed to enable the core regulator.\n"); 74 regulator_disable(priv->io_reg); 75 return; 76 } 77 78 l4f00242t03_reset(priv->reset); 79 80 gpiod_set_value(priv->enable, 1); 81 msleep(60); 82 spi_write(spi, (const u8 *)cmd, ARRAY_SIZE(cmd) * sizeof(u16)); 83 } 84 85 static void l4f00242t03_lcd_powerdown(struct spi_device *spi) 86 { 87 struct l4f00242t03_priv *priv = spi_get_drvdata(spi); 88 89 dev_dbg(&spi->dev, "Powering down LCD\n"); 90 91 gpiod_set_value(priv->enable, 0); 92 93 regulator_disable(priv->io_reg); 94 regulator_disable(priv->core_reg); 95 } 96 97 static int l4f00242t03_lcd_power_get(struct lcd_device *ld) 98 { 99 struct l4f00242t03_priv *priv = lcd_get_data(ld); 100 101 return priv->lcd_state; 102 } 103 104 static int l4f00242t03_lcd_power_set(struct lcd_device *ld, int power) 105 { 106 struct l4f00242t03_priv *priv = lcd_get_data(ld); 107 struct spi_device *spi = priv->spi; 108 109 const u16 slpout = 0x11; 110 const u16 dison = 0x29; 111 112 const u16 slpin = 0x10; 113 const u16 disoff = 0x28; 114 115 if (power <= FB_BLANK_NORMAL) { 116 if (priv->lcd_state <= FB_BLANK_NORMAL) { 117 /* Do nothing, the LCD is running */ 118 } else if (priv->lcd_state < FB_BLANK_POWERDOWN) { 119 dev_dbg(&spi->dev, "Resuming LCD\n"); 120 121 spi_write(spi, (const u8 *)&slpout, sizeof(u16)); 122 msleep(60); 123 spi_write(spi, (const u8 *)&dison, sizeof(u16)); 124 } else { 125 /* priv->lcd_state == FB_BLANK_POWERDOWN */ 126 l4f00242t03_lcd_init(spi); 127 priv->lcd_state = FB_BLANK_VSYNC_SUSPEND; 128 l4f00242t03_lcd_power_set(priv->ld, power); 129 } 130 } else if (power < FB_BLANK_POWERDOWN) { 131 if (priv->lcd_state <= FB_BLANK_NORMAL) { 132 /* Send the display in standby */ 133 dev_dbg(&spi->dev, "Standby the LCD\n"); 134 135 spi_write(spi, (const u8 *)&disoff, sizeof(u16)); 136 msleep(60); 137 spi_write(spi, (const u8 *)&slpin, sizeof(u16)); 138 } else if (priv->lcd_state < FB_BLANK_POWERDOWN) { 139 /* Do nothing, the LCD is already in standby */ 140 } else { 141 /* priv->lcd_state == FB_BLANK_POWERDOWN */ 142 l4f00242t03_lcd_init(spi); 143 priv->lcd_state = FB_BLANK_UNBLANK; 144 l4f00242t03_lcd_power_set(ld, power); 145 } 146 } else { 147 /* power == FB_BLANK_POWERDOWN */ 148 if (priv->lcd_state != FB_BLANK_POWERDOWN) { 149 /* Clear the screen before shutting down */ 150 spi_write(spi, (const u8 *)&disoff, sizeof(u16)); 151 msleep(60); 152 l4f00242t03_lcd_powerdown(spi); 153 } 154 } 155 156 priv->lcd_state = power; 157 158 return 0; 159 } 160 161 static const struct lcd_ops l4f_ops = { 162 .set_power = l4f00242t03_lcd_power_set, 163 .get_power = l4f00242t03_lcd_power_get, 164 }; 165 166 static int l4f00242t03_probe(struct spi_device *spi) 167 { 168 struct l4f00242t03_priv *priv; 169 170 priv = devm_kzalloc(&spi->dev, sizeof(struct l4f00242t03_priv), 171 GFP_KERNEL); 172 if (priv == NULL) 173 return -ENOMEM; 174 175 spi_set_drvdata(spi, priv); 176 spi->bits_per_word = 9; 177 spi_setup(spi); 178 179 priv->spi = spi; 180 181 priv->reset = devm_gpiod_get(&spi->dev, "reset", GPIOD_OUT_HIGH); 182 if (IS_ERR(priv->reset)) 183 return dev_err_probe(&spi->dev, PTR_ERR(priv->reset), 184 "Unable to get the lcd l4f00242t03 reset gpio.\n"); 185 gpiod_set_consumer_name(priv->reset, "lcd l4f00242t03 reset"); 186 187 priv->enable = devm_gpiod_get(&spi->dev, "enable", GPIOD_OUT_LOW); 188 if (IS_ERR(priv->enable)) 189 return dev_err_probe(&spi->dev, PTR_ERR(priv->enable), 190 "Unable to get the lcd l4f00242t03 data en gpio.\n"); 191 gpiod_set_consumer_name(priv->enable, "lcd l4f00242t03 data enable"); 192 193 priv->io_reg = devm_regulator_get(&spi->dev, "vdd"); 194 if (IS_ERR(priv->io_reg)) 195 return dev_err_probe(&spi->dev, PTR_ERR(priv->io_reg), 196 "%s: Unable to get the IO regulator\n", 197 __func__); 198 199 priv->core_reg = devm_regulator_get(&spi->dev, "vcore"); 200 if (IS_ERR(priv->core_reg)) 201 return dev_err_probe(&spi->dev, PTR_ERR(priv->core_reg), 202 "%s: Unable to get the core regulator\n", 203 __func__); 204 205 priv->ld = devm_lcd_device_register(&spi->dev, "l4f00242t03", &spi->dev, 206 priv, &l4f_ops); 207 if (IS_ERR(priv->ld)) 208 return PTR_ERR(priv->ld); 209 210 /* Init the LCD */ 211 l4f00242t03_lcd_init(spi); 212 priv->lcd_state = FB_BLANK_VSYNC_SUSPEND; 213 l4f00242t03_lcd_power_set(priv->ld, FB_BLANK_UNBLANK); 214 215 dev_info(&spi->dev, "Epson l4f00242t03 lcd probed.\n"); 216 217 return 0; 218 } 219 220 static void l4f00242t03_remove(struct spi_device *spi) 221 { 222 struct l4f00242t03_priv *priv = spi_get_drvdata(spi); 223 224 l4f00242t03_lcd_power_set(priv->ld, FB_BLANK_POWERDOWN); 225 } 226 227 static void l4f00242t03_shutdown(struct spi_device *spi) 228 { 229 struct l4f00242t03_priv *priv = spi_get_drvdata(spi); 230 231 if (priv) 232 l4f00242t03_lcd_power_set(priv->ld, FB_BLANK_POWERDOWN); 233 234 } 235 236 static struct spi_driver l4f00242t03_driver = { 237 .driver = { 238 .name = "l4f00242t03", 239 }, 240 .probe = l4f00242t03_probe, 241 .remove = l4f00242t03_remove, 242 .shutdown = l4f00242t03_shutdown, 243 }; 244 245 module_spi_driver(l4f00242t03_driver); 246 247 MODULE_AUTHOR("Alberto Panizzo <maramaopercheseimorto@gmail.com>"); 248 MODULE_DESCRIPTION("EPSON L4F00242T03 LCD"); 249 MODULE_LICENSE("GPL v2"); 250