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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * l4f00242t03.c -- support for Epson L4F00242T03 LCD4 *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.c9 */10 11#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt12 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 23struct 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 33static 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 46static 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 85static 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 97static 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 104static 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 161static const struct lcd_ops l4f_ops = {162 .set_power = l4f00242t03_lcd_power_set,163 .get_power = l4f00242t03_lcd_power_get,164};165 166static int l4f00242t03_probe(struct spi_device *spi)167{168 struct l4f00242t03_priv *priv;169 int ret;170 171 priv = devm_kzalloc(&spi->dev, sizeof(struct l4f00242t03_priv),172 GFP_KERNEL);173 if (priv == NULL)174 return -ENOMEM;175 176 spi_set_drvdata(spi, priv);177 spi->bits_per_word = 9;178 ret = spi_setup(spi);179 if (ret < 0)180 return dev_err_probe(&spi->dev, ret, "Unable to setup spi.\n");181 182 priv->spi = spi;183 184 priv->reset = devm_gpiod_get(&spi->dev, "reset", GPIOD_OUT_HIGH);185 if (IS_ERR(priv->reset))186 return dev_err_probe(&spi->dev, PTR_ERR(priv->reset),187 "Unable to get the lcd l4f00242t03 reset gpio.\n");188 gpiod_set_consumer_name(priv->reset, "lcd l4f00242t03 reset");189 190 priv->enable = devm_gpiod_get(&spi->dev, "enable", GPIOD_OUT_LOW);191 if (IS_ERR(priv->enable))192 return dev_err_probe(&spi->dev, PTR_ERR(priv->enable),193 "Unable to get the lcd l4f00242t03 data en gpio.\n");194 gpiod_set_consumer_name(priv->enable, "lcd l4f00242t03 data enable");195 196 priv->io_reg = devm_regulator_get(&spi->dev, "vdd");197 if (IS_ERR(priv->io_reg))198 return dev_err_probe(&spi->dev, PTR_ERR(priv->io_reg),199 "%s: Unable to get the IO regulator\n",200 __func__);201 202 priv->core_reg = devm_regulator_get(&spi->dev, "vcore");203 if (IS_ERR(priv->core_reg))204 return dev_err_probe(&spi->dev, PTR_ERR(priv->core_reg),205 "%s: Unable to get the core regulator\n",206 __func__);207 208 priv->ld = devm_lcd_device_register(&spi->dev, "l4f00242t03", &spi->dev,209 priv, &l4f_ops);210 if (IS_ERR(priv->ld))211 return PTR_ERR(priv->ld);212 213 /* Init the LCD */214 l4f00242t03_lcd_init(spi);215 priv->lcd_state = FB_BLANK_VSYNC_SUSPEND;216 l4f00242t03_lcd_power_set(priv->ld, FB_BLANK_UNBLANK);217 218 dev_info(&spi->dev, "Epson l4f00242t03 lcd probed.\n");219 220 return 0;221}222 223static void l4f00242t03_remove(struct spi_device *spi)224{225 struct l4f00242t03_priv *priv = spi_get_drvdata(spi);226 227 l4f00242t03_lcd_power_set(priv->ld, FB_BLANK_POWERDOWN);228}229 230static void l4f00242t03_shutdown(struct spi_device *spi)231{232 struct l4f00242t03_priv *priv = spi_get_drvdata(spi);233 234 if (priv)235 l4f00242t03_lcd_power_set(priv->ld, FB_BLANK_POWERDOWN);236 237}238 239static struct spi_driver l4f00242t03_driver = {240 .driver = {241 .name = "l4f00242t03",242 },243 .probe = l4f00242t03_probe,244 .remove = l4f00242t03_remove,245 .shutdown = l4f00242t03_shutdown,246};247 248module_spi_driver(l4f00242t03_driver);249 250MODULE_AUTHOR("Alberto Panizzo <maramaopercheseimorto@gmail.com>");251MODULE_DESCRIPTION("EPSON L4F00242T03 LCD");252MODULE_LICENSE("GPL v2");253