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.h> 18 #include <linux/lcd.h> 19 #include <linux/slab.h> 20 #include <linux/regulator/consumer.h> 21 22 #include <linux/spi/spi.h> 23 #include <linux/spi/l4f00242t03.h> 24 25 struct l4f00242t03_priv { 26 struct spi_device *spi; 27 struct lcd_device *ld; 28 int lcd_state; 29 struct regulator *io_reg; 30 struct regulator *core_reg; 31 }; 32 33 static void l4f00242t03_reset(unsigned int gpio) 34 { 35 pr_debug("l4f00242t03_reset.\n"); 36 gpio_set_value(gpio, 1); 37 mdelay(100); 38 gpio_set_value(gpio, 0); 39 mdelay(10); /* tRES >= 100us */ 40 gpio_set_value(gpio, 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_pdata *pdata = dev_get_platdata(&spi->dev); 49 struct l4f00242t03_priv *priv = spi_get_drvdata(spi); 50 const u16 cmd[] = { 0x36, param(0), 0x3A, param(0x60) }; 51 int ret; 52 53 dev_dbg(&spi->dev, "initializing LCD\n"); 54 55 ret = regulator_set_voltage(priv->io_reg, 1800000, 1800000); 56 if (ret) { 57 dev_err(&spi->dev, "failed to set the IO regulator voltage.\n"); 58 return; 59 } 60 ret = regulator_enable(priv->io_reg); 61 if (ret) { 62 dev_err(&spi->dev, "failed to enable the IO regulator.\n"); 63 return; 64 } 65 66 ret = regulator_set_voltage(priv->core_reg, 2800000, 2800000); 67 if (ret) { 68 dev_err(&spi->dev, "failed to set the core regulator voltage.\n"); 69 regulator_disable(priv->io_reg); 70 return; 71 } 72 ret = regulator_enable(priv->core_reg); 73 if (ret) { 74 dev_err(&spi->dev, "failed to enable the core regulator.\n"); 75 regulator_disable(priv->io_reg); 76 return; 77 } 78 79 l4f00242t03_reset(pdata->reset_gpio); 80 81 gpio_set_value(pdata->data_enable_gpio, 1); 82 msleep(60); 83 spi_write(spi, (const u8 *)cmd, ARRAY_SIZE(cmd) * sizeof(u16)); 84 } 85 86 static void l4f00242t03_lcd_powerdown(struct spi_device *spi) 87 { 88 struct l4f00242t03_pdata *pdata = dev_get_platdata(&spi->dev); 89 struct l4f00242t03_priv *priv = spi_get_drvdata(spi); 90 91 dev_dbg(&spi->dev, "Powering down LCD\n"); 92 93 gpio_set_value(pdata->data_enable_gpio, 0); 94 95 regulator_disable(priv->io_reg); 96 regulator_disable(priv->core_reg); 97 } 98 99 static int l4f00242t03_lcd_power_get(struct lcd_device *ld) 100 { 101 struct l4f00242t03_priv *priv = lcd_get_data(ld); 102 103 return priv->lcd_state; 104 } 105 106 static int l4f00242t03_lcd_power_set(struct lcd_device *ld, int power) 107 { 108 struct l4f00242t03_priv *priv = lcd_get_data(ld); 109 struct spi_device *spi = priv->spi; 110 111 const u16 slpout = 0x11; 112 const u16 dison = 0x29; 113 114 const u16 slpin = 0x10; 115 const u16 disoff = 0x28; 116 117 if (power <= FB_BLANK_NORMAL) { 118 if (priv->lcd_state <= FB_BLANK_NORMAL) { 119 /* Do nothing, the LCD is running */ 120 } else if (priv->lcd_state < FB_BLANK_POWERDOWN) { 121 dev_dbg(&spi->dev, "Resuming LCD\n"); 122 123 spi_write(spi, (const u8 *)&slpout, sizeof(u16)); 124 msleep(60); 125 spi_write(spi, (const u8 *)&dison, sizeof(u16)); 126 } else { 127 /* priv->lcd_state == FB_BLANK_POWERDOWN */ 128 l4f00242t03_lcd_init(spi); 129 priv->lcd_state = FB_BLANK_VSYNC_SUSPEND; 130 l4f00242t03_lcd_power_set(priv->ld, power); 131 } 132 } else if (power < FB_BLANK_POWERDOWN) { 133 if (priv->lcd_state <= FB_BLANK_NORMAL) { 134 /* Send the display in standby */ 135 dev_dbg(&spi->dev, "Standby the LCD\n"); 136 137 spi_write(spi, (const u8 *)&disoff, sizeof(u16)); 138 msleep(60); 139 spi_write(spi, (const u8 *)&slpin, sizeof(u16)); 140 } else if (priv->lcd_state < FB_BLANK_POWERDOWN) { 141 /* Do nothing, the LCD is already in standby */ 142 } else { 143 /* priv->lcd_state == FB_BLANK_POWERDOWN */ 144 l4f00242t03_lcd_init(spi); 145 priv->lcd_state = FB_BLANK_UNBLANK; 146 l4f00242t03_lcd_power_set(ld, power); 147 } 148 } else { 149 /* power == FB_BLANK_POWERDOWN */ 150 if (priv->lcd_state != FB_BLANK_POWERDOWN) { 151 /* Clear the screen before shutting down */ 152 spi_write(spi, (const u8 *)&disoff, sizeof(u16)); 153 msleep(60); 154 l4f00242t03_lcd_powerdown(spi); 155 } 156 } 157 158 priv->lcd_state = power; 159 160 return 0; 161 } 162 163 static struct lcd_ops l4f_ops = { 164 .set_power = l4f00242t03_lcd_power_set, 165 .get_power = l4f00242t03_lcd_power_get, 166 }; 167 168 static int l4f00242t03_probe(struct spi_device *spi) 169 { 170 struct l4f00242t03_priv *priv; 171 struct l4f00242t03_pdata *pdata = dev_get_platdata(&spi->dev); 172 int ret; 173 174 if (pdata == NULL) { 175 dev_err(&spi->dev, "Uninitialized platform data.\n"); 176 return -EINVAL; 177 } 178 179 priv = devm_kzalloc(&spi->dev, sizeof(struct l4f00242t03_priv), 180 GFP_KERNEL); 181 if (priv == NULL) 182 return -ENOMEM; 183 184 spi_set_drvdata(spi, priv); 185 spi->bits_per_word = 9; 186 spi_setup(spi); 187 188 priv->spi = spi; 189 190 ret = devm_gpio_request_one(&spi->dev, pdata->reset_gpio, 191 GPIOF_OUT_INIT_HIGH, "lcd l4f00242t03 reset"); 192 if (ret) { 193 dev_err(&spi->dev, 194 "Unable to get the lcd l4f00242t03 reset gpio.\n"); 195 return ret; 196 } 197 198 ret = devm_gpio_request_one(&spi->dev, pdata->data_enable_gpio, 199 GPIOF_OUT_INIT_LOW, "lcd l4f00242t03 data enable"); 200 if (ret) { 201 dev_err(&spi->dev, 202 "Unable to get the lcd l4f00242t03 data en gpio.\n"); 203 return ret; 204 } 205 206 priv->io_reg = devm_regulator_get(&spi->dev, "vdd"); 207 if (IS_ERR(priv->io_reg)) { 208 dev_err(&spi->dev, "%s: Unable to get the IO regulator\n", 209 __func__); 210 return PTR_ERR(priv->io_reg); 211 } 212 213 priv->core_reg = devm_regulator_get(&spi->dev, "vcore"); 214 if (IS_ERR(priv->core_reg)) { 215 dev_err(&spi->dev, "%s: Unable to get the core regulator\n", 216 __func__); 217 return PTR_ERR(priv->core_reg); 218 } 219 220 priv->ld = devm_lcd_device_register(&spi->dev, "l4f00242t03", &spi->dev, 221 priv, &l4f_ops); 222 if (IS_ERR(priv->ld)) 223 return PTR_ERR(priv->ld); 224 225 /* Init the LCD */ 226 l4f00242t03_lcd_init(spi); 227 priv->lcd_state = FB_BLANK_VSYNC_SUSPEND; 228 l4f00242t03_lcd_power_set(priv->ld, FB_BLANK_UNBLANK); 229 230 dev_info(&spi->dev, "Epson l4f00242t03 lcd probed.\n"); 231 232 return 0; 233 } 234 235 static int l4f00242t03_remove(struct spi_device *spi) 236 { 237 struct l4f00242t03_priv *priv = spi_get_drvdata(spi); 238 239 l4f00242t03_lcd_power_set(priv->ld, FB_BLANK_POWERDOWN); 240 return 0; 241 } 242 243 static void l4f00242t03_shutdown(struct spi_device *spi) 244 { 245 struct l4f00242t03_priv *priv = spi_get_drvdata(spi); 246 247 if (priv) 248 l4f00242t03_lcd_power_set(priv->ld, FB_BLANK_POWERDOWN); 249 250 } 251 252 static struct spi_driver l4f00242t03_driver = { 253 .driver = { 254 .name = "l4f00242t03", 255 }, 256 .probe = l4f00242t03_probe, 257 .remove = l4f00242t03_remove, 258 .shutdown = l4f00242t03_shutdown, 259 }; 260 261 module_spi_driver(l4f00242t03_driver); 262 263 MODULE_AUTHOR("Alberto Panizzo <maramaopercheseimorto@gmail.com>"); 264 MODULE_DESCRIPTION("EPSON L4F00242T03 LCD"); 265 MODULE_LICENSE("GPL v2"); 266