1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * DSI interface to the Samsung S6E63M0 panel.
4  * (C) 2019 Linus Walleij
5  */
6 
7 #include <linux/module.h>
8 #include <linux/delay.h>
9 #include <linux/of_device.h>
10 
11 #include <drm/drm_mipi_dsi.h>
12 #include <drm/drm_print.h>
13 
14 #include "panel-samsung-s6e63m0.h"
15 
16 #define MCS_GLOBAL_PARAM	0xb0
17 #define S6E63M0_DSI_MAX_CHUNK	15 /* CMD + 15 bytes max */
18 
s6e63m0_dsi_dcs_read(struct device * dev,void * trsp,const u8 cmd,u8 * data)19 static int s6e63m0_dsi_dcs_read(struct device *dev, void *trsp,
20 				const u8 cmd, u8 *data)
21 {
22 	struct mipi_dsi_device *dsi = to_mipi_dsi_device(dev);
23 	int ret;
24 
25 	ret = mipi_dsi_dcs_read(dsi, cmd, data, 1);
26 	if (ret < 0) {
27 		dev_err(dev, "could not read DCS CMD %02x\n", cmd);
28 		return ret;
29 	}
30 
31 	dev_dbg(dev, "DSI read CMD %02x = %02x\n", cmd, *data);
32 
33 	return 0;
34 }
35 
s6e63m0_dsi_dcs_write(struct device * dev,void * trsp,const u8 * data,size_t len)36 static int s6e63m0_dsi_dcs_write(struct device *dev, void *trsp,
37 				 const u8 *data, size_t len)
38 {
39 	struct mipi_dsi_device *dsi = to_mipi_dsi_device(dev);
40 	const u8 *seqp = data;
41 	u8 cmd;
42 	u8 cmdwritten;
43 	int remain;
44 	int chunk;
45 	int ret;
46 
47 	dev_dbg(dev, "DSI writing dcs seq: %*ph\n", (int)len, data);
48 
49 	/* Pick out and skip past the DCS command */
50 	cmd = *seqp;
51 	seqp++;
52 	cmdwritten = 0;
53 	remain = len - 1;
54 	chunk = remain;
55 
56 	/* Send max S6E63M0_DSI_MAX_CHUNK bytes at a time */
57 	if (chunk > S6E63M0_DSI_MAX_CHUNK)
58 		chunk = S6E63M0_DSI_MAX_CHUNK;
59 	ret = mipi_dsi_dcs_write(dsi, cmd, seqp, chunk);
60 	if (ret < 0) {
61 		dev_err(dev, "error sending DCS command seq cmd %02x\n", cmd);
62 		return ret;
63 	}
64 	cmdwritten += chunk;
65 	seqp += chunk;
66 
67 	while (cmdwritten < remain) {
68 		chunk = remain - cmdwritten;
69 		if (chunk > S6E63M0_DSI_MAX_CHUNK)
70 			chunk = S6E63M0_DSI_MAX_CHUNK;
71 		ret = mipi_dsi_dcs_write(dsi, MCS_GLOBAL_PARAM, &cmdwritten, 1);
72 		if (ret < 0) {
73 			dev_err(dev, "error sending CMD %02x global param %02x\n",
74 				cmd, cmdwritten);
75 			return ret;
76 		}
77 		ret = mipi_dsi_dcs_write(dsi, cmd, seqp, chunk);
78 		if (ret < 0) {
79 			dev_err(dev, "error sending CMD %02x chunk\n", cmd);
80 			return ret;
81 		}
82 		cmdwritten += chunk;
83 		seqp += chunk;
84 	}
85 	dev_dbg(dev, "sent command %02x %02x bytes\n", cmd, cmdwritten);
86 
87 	usleep_range(8000, 9000);
88 
89 	return 0;
90 }
91 
s6e63m0_dsi_probe(struct mipi_dsi_device * dsi)92 static int s6e63m0_dsi_probe(struct mipi_dsi_device *dsi)
93 {
94 	struct device *dev = &dsi->dev;
95 	int ret;
96 
97 	dsi->lanes = 2;
98 	dsi->format = MIPI_DSI_FMT_RGB888;
99 	dsi->hs_rate = 349440000;
100 	dsi->lp_rate = 9600000;
101 	dsi->mode_flags = MIPI_DSI_MODE_VIDEO |
102 		MIPI_DSI_MODE_VIDEO_BURST;
103 
104 	ret = s6e63m0_probe(dev, NULL, s6e63m0_dsi_dcs_read,
105 			    s6e63m0_dsi_dcs_write, true);
106 	if (ret)
107 		return ret;
108 
109 	ret = mipi_dsi_attach(dsi);
110 	if (ret < 0)
111 		s6e63m0_remove(dev);
112 
113 	return ret;
114 }
115 
s6e63m0_dsi_remove(struct mipi_dsi_device * dsi)116 static void s6e63m0_dsi_remove(struct mipi_dsi_device *dsi)
117 {
118 	mipi_dsi_detach(dsi);
119 	s6e63m0_remove(&dsi->dev);
120 }
121 
122 static const struct of_device_id s6e63m0_dsi_of_match[] = {
123 	{ .compatible = "samsung,s6e63m0" },
124 	{ /* sentinel */ }
125 };
126 MODULE_DEVICE_TABLE(of, s6e63m0_dsi_of_match);
127 
128 static struct mipi_dsi_driver s6e63m0_dsi_driver = {
129 	.probe			= s6e63m0_dsi_probe,
130 	.remove			= s6e63m0_dsi_remove,
131 	.driver			= {
132 		.name		= "panel-samsung-s6e63m0",
133 		.of_match_table = s6e63m0_dsi_of_match,
134 	},
135 };
136 module_mipi_dsi_driver(s6e63m0_dsi_driver);
137 
138 MODULE_AUTHOR("Linus Walleij <linusw@kernel.org>");
139 MODULE_DESCRIPTION("s6e63m0 LCD DSI Driver");
140 MODULE_LICENSE("GPL v2");
141