xref: /OK3568_Linux_fs/kernel/drivers/gpu/drm/panel/panel-samsung-s6e63m0-spi.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun 
3*4882a593Smuzhiyun #include <linux/device.h>
4*4882a593Smuzhiyun #include <linux/module.h>
5*4882a593Smuzhiyun #include <linux/spi/spi.h>
6*4882a593Smuzhiyun #include <linux/delay.h>
7*4882a593Smuzhiyun 
8*4882a593Smuzhiyun #include <drm/drm_print.h>
9*4882a593Smuzhiyun 
10*4882a593Smuzhiyun #include "panel-samsung-s6e63m0.h"
11*4882a593Smuzhiyun 
12*4882a593Smuzhiyun #define DATA_MASK	0x100
13*4882a593Smuzhiyun 
s6e63m0_spi_dcs_read(struct device * dev,const u8 cmd,u8 * data)14*4882a593Smuzhiyun static int s6e63m0_spi_dcs_read(struct device *dev, const u8 cmd, u8 *data)
15*4882a593Smuzhiyun {
16*4882a593Smuzhiyun 	/*
17*4882a593Smuzhiyun 	 * FIXME: implement reading DCS commands over SPI so we can
18*4882a593Smuzhiyun 	 * properly identify which physical panel is connected.
19*4882a593Smuzhiyun 	 */
20*4882a593Smuzhiyun 	*data = 0;
21*4882a593Smuzhiyun 
22*4882a593Smuzhiyun 	return 0;
23*4882a593Smuzhiyun }
24*4882a593Smuzhiyun 
s6e63m0_spi_write_word(struct device * dev,u16 data)25*4882a593Smuzhiyun static int s6e63m0_spi_write_word(struct device *dev, u16 data)
26*4882a593Smuzhiyun {
27*4882a593Smuzhiyun 	struct spi_device *spi = to_spi_device(dev);
28*4882a593Smuzhiyun 	struct spi_transfer xfer = {
29*4882a593Smuzhiyun 		.len	= 2,
30*4882a593Smuzhiyun 		.tx_buf = &data,
31*4882a593Smuzhiyun 	};
32*4882a593Smuzhiyun 	struct spi_message msg;
33*4882a593Smuzhiyun 
34*4882a593Smuzhiyun 	spi_message_init(&msg);
35*4882a593Smuzhiyun 	spi_message_add_tail(&xfer, &msg);
36*4882a593Smuzhiyun 
37*4882a593Smuzhiyun 	return spi_sync(spi, &msg);
38*4882a593Smuzhiyun }
39*4882a593Smuzhiyun 
s6e63m0_spi_dcs_write(struct device * dev,const u8 * data,size_t len)40*4882a593Smuzhiyun static int s6e63m0_spi_dcs_write(struct device *dev, const u8 *data, size_t len)
41*4882a593Smuzhiyun {
42*4882a593Smuzhiyun 	int ret = 0;
43*4882a593Smuzhiyun 
44*4882a593Smuzhiyun 	dev_dbg(dev, "SPI writing dcs seq: %*ph\n", (int)len, data);
45*4882a593Smuzhiyun 	ret = s6e63m0_spi_write_word(dev, *data);
46*4882a593Smuzhiyun 
47*4882a593Smuzhiyun 	while (!ret && --len) {
48*4882a593Smuzhiyun 		++data;
49*4882a593Smuzhiyun 		ret = s6e63m0_spi_write_word(dev, *data | DATA_MASK);
50*4882a593Smuzhiyun 	}
51*4882a593Smuzhiyun 
52*4882a593Smuzhiyun 	if (ret) {
53*4882a593Smuzhiyun 		dev_err(dev, "SPI error %d writing dcs seq: %*ph\n", ret,
54*4882a593Smuzhiyun 			(int)len, data);
55*4882a593Smuzhiyun 	}
56*4882a593Smuzhiyun 
57*4882a593Smuzhiyun 	usleep_range(300, 310);
58*4882a593Smuzhiyun 
59*4882a593Smuzhiyun 	return ret;
60*4882a593Smuzhiyun }
61*4882a593Smuzhiyun 
s6e63m0_spi_probe(struct spi_device * spi)62*4882a593Smuzhiyun static int s6e63m0_spi_probe(struct spi_device *spi)
63*4882a593Smuzhiyun {
64*4882a593Smuzhiyun 	struct device *dev = &spi->dev;
65*4882a593Smuzhiyun 	int ret;
66*4882a593Smuzhiyun 
67*4882a593Smuzhiyun 	spi->bits_per_word = 9;
68*4882a593Smuzhiyun 	spi->mode = SPI_MODE_3;
69*4882a593Smuzhiyun 	ret = spi_setup(spi);
70*4882a593Smuzhiyun 	if (ret < 0) {
71*4882a593Smuzhiyun 		dev_err(dev, "spi setup failed.\n");
72*4882a593Smuzhiyun 		return ret;
73*4882a593Smuzhiyun 	}
74*4882a593Smuzhiyun 	return s6e63m0_probe(dev, s6e63m0_spi_dcs_read, s6e63m0_spi_dcs_write,
75*4882a593Smuzhiyun 			     false);
76*4882a593Smuzhiyun }
77*4882a593Smuzhiyun 
s6e63m0_spi_remove(struct spi_device * spi)78*4882a593Smuzhiyun static int s6e63m0_spi_remove(struct spi_device *spi)
79*4882a593Smuzhiyun {
80*4882a593Smuzhiyun 	return s6e63m0_remove(&spi->dev);
81*4882a593Smuzhiyun }
82*4882a593Smuzhiyun 
83*4882a593Smuzhiyun static const struct of_device_id s6e63m0_spi_of_match[] = {
84*4882a593Smuzhiyun 	{ .compatible = "samsung,s6e63m0" },
85*4882a593Smuzhiyun 	{ /* sentinel */ }
86*4882a593Smuzhiyun };
87*4882a593Smuzhiyun MODULE_DEVICE_TABLE(of, s6e63m0_spi_of_match);
88*4882a593Smuzhiyun 
89*4882a593Smuzhiyun static struct spi_driver s6e63m0_spi_driver = {
90*4882a593Smuzhiyun 	.probe			= s6e63m0_spi_probe,
91*4882a593Smuzhiyun 	.remove			= s6e63m0_spi_remove,
92*4882a593Smuzhiyun 	.driver			= {
93*4882a593Smuzhiyun 		.name		= "panel-samsung-s6e63m0",
94*4882a593Smuzhiyun 		.of_match_table = s6e63m0_spi_of_match,
95*4882a593Smuzhiyun 	},
96*4882a593Smuzhiyun };
97*4882a593Smuzhiyun module_spi_driver(s6e63m0_spi_driver);
98*4882a593Smuzhiyun 
99*4882a593Smuzhiyun MODULE_AUTHOR("Paweł Chmiel <pawel.mikolaj.chmiel@gmail.com>");
100*4882a593Smuzhiyun MODULE_DESCRIPTION("s6e63m0 LCD SPI Driver");
101*4882a593Smuzhiyun MODULE_LICENSE("GPL v2");
102