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(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 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(&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
220static 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
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(priv->ld, 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