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
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(desc: gpiod, value: 1);
37 mdelay(100);
38 gpiod_set_value(desc: gpiod, value: 0);
39 mdelay(10); /* tRES >= 100us */
40 gpiod_set_value(desc: gpiod, value: 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(regulator: priv->io_reg, min_uV: 1800000, max_uV: 1800000);
55 if (ret) {
56 dev_err(&spi->dev, "failed to set the IO regulator voltage.\n");
57 return;
58 }
59 ret = regulator_enable(regulator: 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(regulator: priv->core_reg, min_uV: 2800000, max_uV: 2800000);
66 if (ret) {
67 dev_err(&spi->dev, "failed to set the core regulator voltage.\n");
68 regulator_disable(regulator: priv->io_reg);
69 return;
70 }
71 ret = regulator_enable(regulator: priv->core_reg);
72 if (ret) {
73 dev_err(&spi->dev, "failed to enable the core regulator.\n");
74 regulator_disable(regulator: priv->io_reg);
75 return;
76 }
77
78 l4f00242t03_reset(gpiod: priv->reset);
79
80 gpiod_set_value(desc: priv->enable, value: 1);
81 msleep(msecs: 60);
82 spi_write(spi, buf: (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(desc: priv->enable, value: 0);
92
93 regulator_disable(regulator: priv->io_reg);
94 regulator_disable(regulator: 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_dev: 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_dev: 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, buf: (const u8 *)&slpout, len: sizeof(u16));
122 msleep(msecs: 60);
123 spi_write(spi, buf: (const u8 *)&dison, len: 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(ld: 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, buf: (const u8 *)&disoff, len: sizeof(u16));
136 msleep(msecs: 60);
137 spi_write(spi, buf: (const u8 *)&slpin, len: 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, buf: (const u8 *)&disoff, len: sizeof(u16));
151 msleep(msecs: 60);
152 l4f00242t03_lcd_powerdown(spi);
153 }
154 }
155
156 priv->lcd_state = power;
157
158 return 0;
159}
160
161static 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
170 priv = devm_kzalloc(dev: &spi->dev, size: sizeof(struct l4f00242t03_priv),
171 GFP_KERNEL);
172 if (priv == NULL)
173 return -ENOMEM;
174
175 spi_set_drvdata(spi, data: priv);
176 spi->bits_per_word = 9;
177 spi_setup(spi);
178
179 priv->spi = spi;
180
181 priv->reset = devm_gpiod_get(dev: &spi->dev, con_id: "reset", flags: GPIOD_OUT_HIGH);
182 if (IS_ERR(ptr: priv->reset))
183 return dev_err_probe(dev: &spi->dev, err: PTR_ERR(ptr: priv->reset),
184 fmt: "Unable to get the lcd l4f00242t03 reset gpio.\n");
185 gpiod_set_consumer_name(desc: priv->reset, name: "lcd l4f00242t03 reset");
186
187 priv->enable = devm_gpiod_get(dev: &spi->dev, con_id: "enable", flags: GPIOD_OUT_LOW);
188 if (IS_ERR(ptr: priv->enable))
189 return dev_err_probe(dev: &spi->dev, err: PTR_ERR(ptr: priv->enable),
190 fmt: "Unable to get the lcd l4f00242t03 data en gpio.\n");
191 gpiod_set_consumer_name(desc: priv->enable, name: "lcd l4f00242t03 data enable");
192
193 priv->io_reg = devm_regulator_get(dev: &spi->dev, id: "vdd");
194 if (IS_ERR(ptr: priv->io_reg))
195 return dev_err_probe(dev: &spi->dev, err: PTR_ERR(ptr: priv->io_reg),
196 fmt: "%s: Unable to get the IO regulator\n",
197 __func__);
198
199 priv->core_reg = devm_regulator_get(dev: &spi->dev, id: "vcore");
200 if (IS_ERR(ptr: priv->core_reg))
201 return dev_err_probe(dev: &spi->dev, err: PTR_ERR(ptr: priv->core_reg),
202 fmt: "%s: Unable to get the core regulator\n",
203 __func__);
204
205 priv->ld = devm_lcd_device_register(dev: &spi->dev, name: "l4f00242t03", parent: &spi->dev,
206 devdata: priv, ops: &l4f_ops);
207 if (IS_ERR(ptr: priv->ld))
208 return PTR_ERR(ptr: 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(ld: priv->ld, power: FB_BLANK_UNBLANK);
214
215 dev_info(&spi->dev, "Epson l4f00242t03 lcd probed.\n");
216
217 return 0;
218}
219
220static void l4f00242t03_remove(struct spi_device *spi)
221{
222 struct l4f00242t03_priv *priv = spi_get_drvdata(spi);
223
224 l4f00242t03_lcd_power_set(ld: priv->ld, power: FB_BLANK_POWERDOWN);
225}
226
227static 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(ld: priv->ld, power: FB_BLANK_POWERDOWN);
233
234}
235
236static 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
245module_spi_driver(l4f00242t03_driver);
246
247MODULE_AUTHOR("Alberto Panizzo <maramaopercheseimorto@gmail.com>");
248MODULE_DESCRIPTION("EPSON L4F00242T03 LCD");
249MODULE_LICENSE("GPL v2");
250

source code of linux/drivers/video/backlight/l4f00242t03.c