]> git.proxmox.com Git - mirror_ubuntu-focal-kernel.git/blame - drivers/video/backlight/ltv350qv.c
Merge tag '9p-for-5.4' of git://github.com/martinetd/linux
[mirror_ubuntu-focal-kernel.git] / drivers / video / backlight / ltv350qv.c
CommitLineData
d2912cb1 1// SPDX-License-Identifier: GPL-2.0-only
18f65c79
HS
2/*
3 * Power control for Samsung LTV350QV Quarter VGA LCD Panel
4 *
5 * Copyright (C) 2006, 2007 Atmel Corporation
18f65c79
HS
6 */
7#include <linux/delay.h>
8#include <linux/err.h>
9#include <linux/fb.h>
10#include <linux/init.h>
11#include <linux/lcd.h>
12#include <linux/module.h>
5a0e3ad6 13#include <linux/slab.h>
18f65c79
HS
14#include <linux/spi/spi.h>
15
16#include "ltv350qv.h"
17
18#define POWER_IS_ON(pwr) ((pwr) <= FB_BLANK_NORMAL)
19
20struct ltv350qv {
21 struct spi_device *spi;
22 u8 *buffer;
23 int power;
24 struct lcd_device *ld;
25};
26
27/*
28 * The power-on and power-off sequences are taken from the
29 * LTV350QV-F04 data sheet from Samsung. The register definitions are
30 * taken from the S6F2002 command list also from Samsung. Both
31 * documents are distributed with the AVR32 Linux BSP CD from Atmel.
32 *
33 * There's still some voodoo going on here, but it's a lot better than
34 * in the first incarnation of the driver where all we had was the raw
35 * numbers from the initialization sequence.
36 */
37static int ltv350qv_write_reg(struct ltv350qv *lcd, u8 reg, u16 val)
38{
39 struct spi_message msg;
40 struct spi_transfer index_xfer = {
41 .len = 3,
42 .cs_change = 1,
43 };
44 struct spi_transfer value_xfer = {
45 .len = 3,
46 };
47
48 spi_message_init(&msg);
49
50 /* register index */
51 lcd->buffer[0] = LTV_OPC_INDEX;
52 lcd->buffer[1] = 0x00;
53 lcd->buffer[2] = reg & 0x7f;
54 index_xfer.tx_buf = lcd->buffer;
55 spi_message_add_tail(&index_xfer, &msg);
56
57 /* register value */
58 lcd->buffer[4] = LTV_OPC_DATA;
59 lcd->buffer[5] = val >> 8;
60 lcd->buffer[6] = val;
61 value_xfer.tx_buf = lcd->buffer + 4;
62 spi_message_add_tail(&value_xfer, &msg);
63
64 return spi_sync(lcd->spi, &msg);
65}
66
67/* The comments are taken straight from the data sheet */
68static int ltv350qv_power_on(struct ltv350qv *lcd)
69{
70 int ret;
71
72 /* Power On Reset Display off State */
73 if (ltv350qv_write_reg(lcd, LTV_PWRCTL1, 0x0000))
74 goto err;
a08e1a37 75 usleep_range(15000, 16000);
18f65c79
HS
76
77 /* Power Setting Function 1 */
78 if (ltv350qv_write_reg(lcd, LTV_PWRCTL1, LTV_VCOM_DISABLE))
79 goto err;
80 if (ltv350qv_write_reg(lcd, LTV_PWRCTL2, LTV_VCOML_ENABLE))
81 goto err_power1;
82
83 /* Power Setting Function 2 */
84 if (ltv350qv_write_reg(lcd, LTV_PWRCTL1,
85 LTV_VCOM_DISABLE | LTV_DRIVE_CURRENT(5)
86 | LTV_SUPPLY_CURRENT(5)))
87 goto err_power2;
88
89 msleep(55);
90
91 /* Instruction Setting */
92 ret = ltv350qv_write_reg(lcd, LTV_IFCTL,
93 LTV_NMD | LTV_REV | LTV_NL(0x1d));
94 ret |= ltv350qv_write_reg(lcd, LTV_DATACTL,
95 LTV_DS_SAME | LTV_CHS_480
96 | LTV_DF_RGB | LTV_RGB_BGR);
97 ret |= ltv350qv_write_reg(lcd, LTV_ENTRY_MODE,
98 LTV_VSPL_ACTIVE_LOW
99 | LTV_HSPL_ACTIVE_LOW
100 | LTV_DPL_SAMPLE_RISING
101 | LTV_EPL_ACTIVE_LOW
102 | LTV_SS_RIGHT_TO_LEFT);
103 ret |= ltv350qv_write_reg(lcd, LTV_GATECTL1, LTV_CLW(3));
104 ret |= ltv350qv_write_reg(lcd, LTV_GATECTL2,
105 LTV_NW_INV_1LINE | LTV_FWI(3));
106 ret |= ltv350qv_write_reg(lcd, LTV_VBP, 0x000a);
107 ret |= ltv350qv_write_reg(lcd, LTV_HBP, 0x0021);
108 ret |= ltv350qv_write_reg(lcd, LTV_SOTCTL, LTV_SDT(3) | LTV_EQ(0));
109 ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(0), 0x0103);
110 ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(1), 0x0301);
111 ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(2), 0x1f0f);
112 ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(3), 0x1f0f);
113 ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(4), 0x0707);
114 ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(5), 0x0307);
115 ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(6), 0x0707);
116 ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(7), 0x0000);
117 ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(8), 0x0004);
118 ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(9), 0x0000);
119 if (ret)
120 goto err_settings;
121
122 /* Wait more than 2 frames */
123 msleep(20);
124
125 /* Display On Sequence */
126 ret = ltv350qv_write_reg(lcd, LTV_PWRCTL1,
127 LTV_VCOM_DISABLE | LTV_VCOMOUT_ENABLE
128 | LTV_POWER_ON | LTV_DRIVE_CURRENT(5)
129 | LTV_SUPPLY_CURRENT(5));
130 ret |= ltv350qv_write_reg(lcd, LTV_GATECTL2,
131 LTV_NW_INV_1LINE | LTV_DSC | LTV_FWI(3));
132 if (ret)
133 goto err_disp_on;
134
135 /* Display should now be ON. Phew. */
136 return 0;
137
138err_disp_on:
139 /*
140 * Try to recover. Error handling probably isn't very useful
141 * at this point, just make a best effort to switch the panel
142 * off.
143 */
144 ltv350qv_write_reg(lcd, LTV_PWRCTL1,
145 LTV_VCOM_DISABLE | LTV_DRIVE_CURRENT(5)
146 | LTV_SUPPLY_CURRENT(5));
147 ltv350qv_write_reg(lcd, LTV_GATECTL2,
148 LTV_NW_INV_1LINE | LTV_FWI(3));
149err_settings:
150err_power2:
151err_power1:
152 ltv350qv_write_reg(lcd, LTV_PWRCTL2, 0x0000);
a08e1a37 153 usleep_range(1000, 1100);
18f65c79
HS
154err:
155 ltv350qv_write_reg(lcd, LTV_PWRCTL1, LTV_VCOM_DISABLE);
156 return -EIO;
157}
158
159static int ltv350qv_power_off(struct ltv350qv *lcd)
160{
161 int ret;
162
163 /* Display Off Sequence */
164 ret = ltv350qv_write_reg(lcd, LTV_PWRCTL1,
165 LTV_VCOM_DISABLE
166 | LTV_DRIVE_CURRENT(5)
167 | LTV_SUPPLY_CURRENT(5));
168 ret |= ltv350qv_write_reg(lcd, LTV_GATECTL2,
169 LTV_NW_INV_1LINE | LTV_FWI(3));
170
171 /* Power down setting 1 */
172 ret |= ltv350qv_write_reg(lcd, LTV_PWRCTL2, 0x0000);
173
174 /* Wait at least 1 ms */
a08e1a37 175 usleep_range(1000, 1100);
18f65c79
HS
176
177 /* Power down setting 2 */
178 ret |= ltv350qv_write_reg(lcd, LTV_PWRCTL1, LTV_VCOM_DISABLE);
179
180 /*
181 * No point in trying to recover here. If we can't switch the
182 * panel off, what are we supposed to do other than inform the
183 * user about the failure?
184 */
185 if (ret)
186 return -EIO;
187
188 /* Display power should now be OFF */
189 return 0;
190}
191
192static int ltv350qv_power(struct ltv350qv *lcd, int power)
193{
194 int ret = 0;
195
196 if (POWER_IS_ON(power) && !POWER_IS_ON(lcd->power))
197 ret = ltv350qv_power_on(lcd);
198 else if (!POWER_IS_ON(power) && POWER_IS_ON(lcd->power))
199 ret = ltv350qv_power_off(lcd);
200
201 if (!ret)
202 lcd->power = power;
203
204 return ret;
205}
206
207static int ltv350qv_set_power(struct lcd_device *ld, int power)
208{
209 struct ltv350qv *lcd = lcd_get_data(ld);
210
211 return ltv350qv_power(lcd, power);
212}
213
214static int ltv350qv_get_power(struct lcd_device *ld)
215{
216 struct ltv350qv *lcd = lcd_get_data(ld);
217
218 return lcd->power;
219}
220
221static struct lcd_ops ltv_ops = {
222 .get_power = ltv350qv_get_power,
223 .set_power = ltv350qv_set_power,
224};
225
1b9e450d 226static int ltv350qv_probe(struct spi_device *spi)
18f65c79
HS
227{
228 struct ltv350qv *lcd;
229 struct lcd_device *ld;
230 int ret;
231
ab03e047 232 lcd = devm_kzalloc(&spi->dev, sizeof(struct ltv350qv), GFP_KERNEL);
18f65c79
HS
233 if (!lcd)
234 return -ENOMEM;
235
236 lcd->spi = spi;
237 lcd->power = FB_BLANK_POWERDOWN;
ab03e047
JH
238 lcd->buffer = devm_kzalloc(&spi->dev, 8, GFP_KERNEL);
239 if (!lcd->buffer)
240 return -ENOMEM;
18f65c79 241
e8796d9f
JH
242 ld = devm_lcd_device_register(&spi->dev, "ltv350qv", &spi->dev, lcd,
243 &ltv_ops);
ab03e047
JH
244 if (IS_ERR(ld))
245 return PTR_ERR(ld);
246
18f65c79
HS
247 lcd->ld = ld;
248
249 ret = ltv350qv_power(lcd, FB_BLANK_UNBLANK);
250 if (ret)
e8796d9f 251 return ret;
18f65c79 252
91c665b0 253 spi_set_drvdata(spi, lcd);
18f65c79
HS
254
255 return 0;
18f65c79
HS
256}
257
7e4b9d0b 258static int ltv350qv_remove(struct spi_device *spi)
18f65c79 259{
91c665b0 260 struct ltv350qv *lcd = spi_get_drvdata(spi);
18f65c79
HS
261
262 ltv350qv_power(lcd, FB_BLANK_POWERDOWN);
18f65c79
HS
263 return 0;
264}
265
a71ed77b
JH
266#ifdef CONFIG_PM_SLEEP
267static int ltv350qv_suspend(struct device *dev)
18f65c79 268{
a71ed77b 269 struct ltv350qv *lcd = dev_get_drvdata(dev);
18f65c79
HS
270
271 return ltv350qv_power(lcd, FB_BLANK_POWERDOWN);
272}
273
a71ed77b 274static int ltv350qv_resume(struct device *dev)
18f65c79 275{
a71ed77b 276 struct ltv350qv *lcd = dev_get_drvdata(dev);
18f65c79
HS
277
278 return ltv350qv_power(lcd, FB_BLANK_UNBLANK);
279}
18f65c79
HS
280#endif
281
a71ed77b
JH
282static SIMPLE_DEV_PM_OPS(ltv350qv_pm_ops, ltv350qv_suspend, ltv350qv_resume);
283
18f65c79
HS
284/* Power down all displays on reboot, poweroff or halt */
285static void ltv350qv_shutdown(struct spi_device *spi)
286{
91c665b0 287 struct ltv350qv *lcd = spi_get_drvdata(spi);
18f65c79
HS
288
289 ltv350qv_power(lcd, FB_BLANK_POWERDOWN);
290}
291
292static struct spi_driver ltv350qv_driver = {
293 .driver = {
294 .name = "ltv350qv",
a71ed77b 295 .pm = &ltv350qv_pm_ops,
18f65c79
HS
296 },
297
298 .probe = ltv350qv_probe,
d1723fa2 299 .remove = ltv350qv_remove,
18f65c79 300 .shutdown = ltv350qv_shutdown,
18f65c79
HS
301};
302
462dd838 303module_spi_driver(ltv350qv_driver);
18f65c79 304
e05503ef 305MODULE_AUTHOR("Haavard Skinnemoen (Atmel)");
18f65c79
HS
306MODULE_DESCRIPTION("Samsung LTV350QV LCD Driver");
307MODULE_LICENSE("GPL");
e0626e38 308MODULE_ALIAS("spi:ltv350qv");