xref: /openbmc/linux/drivers/gpu/drm/tiny/st7735r.c (revision 20e2fc42)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * DRM driver for Sitronix ST7735R panels
4  *
5  * Copyright 2017 David Lechner <david@lechnology.com>
6  */
7 
8 #include <linux/backlight.h>
9 #include <linux/delay.h>
10 #include <linux/dma-buf.h>
11 #include <linux/gpio/consumer.h>
12 #include <linux/module.h>
13 #include <linux/property.h>
14 #include <linux/spi/spi.h>
15 #include <video/mipi_display.h>
16 
17 #include <drm/drm_atomic_helper.h>
18 #include <drm/drm_drv.h>
19 #include <drm/drm_fb_helper.h>
20 #include <drm/drm_gem_cma_helper.h>
21 #include <drm/drm_gem_framebuffer_helper.h>
22 #include <drm/drm_mipi_dbi.h>
23 
24 #define ST7735R_FRMCTR1		0xb1
25 #define ST7735R_FRMCTR2		0xb2
26 #define ST7735R_FRMCTR3		0xb3
27 #define ST7735R_INVCTR		0xb4
28 #define ST7735R_PWCTR1		0xc0
29 #define ST7735R_PWCTR2		0xc1
30 #define ST7735R_PWCTR3		0xc2
31 #define ST7735R_PWCTR4		0xc3
32 #define ST7735R_PWCTR5		0xc4
33 #define ST7735R_VMCTR1		0xc5
34 #define ST7735R_GAMCTRP1	0xe0
35 #define ST7735R_GAMCTRN1	0xe1
36 
37 #define ST7735R_MY	BIT(7)
38 #define ST7735R_MX	BIT(6)
39 #define ST7735R_MV	BIT(5)
40 
41 static void jd_t18003_t01_pipe_enable(struct drm_simple_display_pipe *pipe,
42 				      struct drm_crtc_state *crtc_state,
43 				      struct drm_plane_state *plane_state)
44 {
45 	struct mipi_dbi_dev *dbidev = drm_to_mipi_dbi_dev(pipe->crtc.dev);
46 	struct mipi_dbi *dbi = &dbidev->dbi;
47 	int ret, idx;
48 	u8 addr_mode;
49 
50 	if (!drm_dev_enter(pipe->crtc.dev, &idx))
51 		return;
52 
53 	DRM_DEBUG_KMS("\n");
54 
55 	ret = mipi_dbi_poweron_reset(dbidev);
56 	if (ret)
57 		goto out_exit;
58 
59 	msleep(150);
60 
61 	mipi_dbi_command(dbi, MIPI_DCS_EXIT_SLEEP_MODE);
62 	msleep(500);
63 
64 	mipi_dbi_command(dbi, ST7735R_FRMCTR1, 0x01, 0x2c, 0x2d);
65 	mipi_dbi_command(dbi, ST7735R_FRMCTR2, 0x01, 0x2c, 0x2d);
66 	mipi_dbi_command(dbi, ST7735R_FRMCTR3, 0x01, 0x2c, 0x2d, 0x01, 0x2c,
67 			 0x2d);
68 	mipi_dbi_command(dbi, ST7735R_INVCTR, 0x07);
69 	mipi_dbi_command(dbi, ST7735R_PWCTR1, 0xa2, 0x02, 0x84);
70 	mipi_dbi_command(dbi, ST7735R_PWCTR2, 0xc5);
71 	mipi_dbi_command(dbi, ST7735R_PWCTR3, 0x0a, 0x00);
72 	mipi_dbi_command(dbi, ST7735R_PWCTR4, 0x8a, 0x2a);
73 	mipi_dbi_command(dbi, ST7735R_PWCTR5, 0x8a, 0xee);
74 	mipi_dbi_command(dbi, ST7735R_VMCTR1, 0x0e);
75 	mipi_dbi_command(dbi, MIPI_DCS_EXIT_INVERT_MODE);
76 	switch (dbidev->rotation) {
77 	default:
78 		addr_mode = ST7735R_MX | ST7735R_MY;
79 		break;
80 	case 90:
81 		addr_mode = ST7735R_MX | ST7735R_MV;
82 		break;
83 	case 180:
84 		addr_mode = 0;
85 		break;
86 	case 270:
87 		addr_mode = ST7735R_MY | ST7735R_MV;
88 		break;
89 	}
90 	mipi_dbi_command(dbi, MIPI_DCS_SET_ADDRESS_MODE, addr_mode);
91 	mipi_dbi_command(dbi, MIPI_DCS_SET_PIXEL_FORMAT,
92 			 MIPI_DCS_PIXEL_FMT_16BIT);
93 	mipi_dbi_command(dbi, ST7735R_GAMCTRP1, 0x02, 0x1c, 0x07, 0x12, 0x37,
94 			 0x32, 0x29, 0x2d, 0x29, 0x25, 0x2b, 0x39, 0x00, 0x01,
95 			 0x03, 0x10);
96 	mipi_dbi_command(dbi, ST7735R_GAMCTRN1, 0x03, 0x1d, 0x07, 0x06, 0x2e,
97 			 0x2c, 0x29, 0x2d, 0x2e, 0x2e, 0x37, 0x3f, 0x00, 0x00,
98 			 0x02, 0x10);
99 	mipi_dbi_command(dbi, MIPI_DCS_SET_DISPLAY_ON);
100 
101 	msleep(100);
102 
103 	mipi_dbi_command(dbi, MIPI_DCS_ENTER_NORMAL_MODE);
104 
105 	msleep(20);
106 
107 	mipi_dbi_enable_flush(dbidev, crtc_state, plane_state);
108 out_exit:
109 	drm_dev_exit(idx);
110 }
111 
112 static const struct drm_simple_display_pipe_funcs jd_t18003_t01_pipe_funcs = {
113 	.enable		= jd_t18003_t01_pipe_enable,
114 	.disable	= mipi_dbi_pipe_disable,
115 	.update		= mipi_dbi_pipe_update,
116 	.prepare_fb	= drm_gem_fb_simple_display_pipe_prepare_fb,
117 };
118 
119 static const struct drm_display_mode jd_t18003_t01_mode = {
120 	DRM_SIMPLE_MODE(128, 160, 28, 35),
121 };
122 
123 DEFINE_DRM_GEM_CMA_FOPS(st7735r_fops);
124 
125 static struct drm_driver st7735r_driver = {
126 	.driver_features	= DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC,
127 	.fops			= &st7735r_fops,
128 	.release		= mipi_dbi_release,
129 	DRM_GEM_CMA_VMAP_DRIVER_OPS,
130 	.debugfs_init		= mipi_dbi_debugfs_init,
131 	.name			= "st7735r",
132 	.desc			= "Sitronix ST7735R",
133 	.date			= "20171128",
134 	.major			= 1,
135 	.minor			= 0,
136 };
137 
138 static const struct of_device_id st7735r_of_match[] = {
139 	{ .compatible = "jianda,jd-t18003-t01" },
140 	{ },
141 };
142 MODULE_DEVICE_TABLE(of, st7735r_of_match);
143 
144 static const struct spi_device_id st7735r_id[] = {
145 	{ "jd-t18003-t01", 0 },
146 	{ },
147 };
148 MODULE_DEVICE_TABLE(spi, st7735r_id);
149 
150 static int st7735r_probe(struct spi_device *spi)
151 {
152 	struct device *dev = &spi->dev;
153 	struct mipi_dbi_dev *dbidev;
154 	struct drm_device *drm;
155 	struct mipi_dbi *dbi;
156 	struct gpio_desc *dc;
157 	u32 rotation = 0;
158 	int ret;
159 
160 	dbidev = kzalloc(sizeof(*dbidev), GFP_KERNEL);
161 	if (!dbidev)
162 		return -ENOMEM;
163 
164 	dbi = &dbidev->dbi;
165 	drm = &dbidev->drm;
166 	ret = devm_drm_dev_init(dev, drm, &st7735r_driver);
167 	if (ret) {
168 		kfree(dbidev);
169 		return ret;
170 	}
171 
172 	drm_mode_config_init(drm);
173 
174 	dbi->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
175 	if (IS_ERR(dbi->reset)) {
176 		DRM_DEV_ERROR(dev, "Failed to get gpio 'reset'\n");
177 		return PTR_ERR(dbi->reset);
178 	}
179 
180 	dc = devm_gpiod_get(dev, "dc", GPIOD_OUT_LOW);
181 	if (IS_ERR(dc)) {
182 		DRM_DEV_ERROR(dev, "Failed to get gpio 'dc'\n");
183 		return PTR_ERR(dc);
184 	}
185 
186 	dbidev->backlight = devm_of_find_backlight(dev);
187 	if (IS_ERR(dbidev->backlight))
188 		return PTR_ERR(dbidev->backlight);
189 
190 	device_property_read_u32(dev, "rotation", &rotation);
191 
192 	ret = mipi_dbi_spi_init(spi, dbi, dc);
193 	if (ret)
194 		return ret;
195 
196 	/* Cannot read from Adafruit 1.8" display via SPI */
197 	dbi->read_commands = NULL;
198 
199 	ret = mipi_dbi_dev_init(dbidev, &jd_t18003_t01_pipe_funcs, &jd_t18003_t01_mode, rotation);
200 	if (ret)
201 		return ret;
202 
203 	drm_mode_config_reset(drm);
204 
205 	ret = drm_dev_register(drm, 0);
206 	if (ret)
207 		return ret;
208 
209 	spi_set_drvdata(spi, drm);
210 
211 	drm_fbdev_generic_setup(drm, 0);
212 
213 	return 0;
214 }
215 
216 static int st7735r_remove(struct spi_device *spi)
217 {
218 	struct drm_device *drm = spi_get_drvdata(spi);
219 
220 	drm_dev_unplug(drm);
221 	drm_atomic_helper_shutdown(drm);
222 
223 	return 0;
224 }
225 
226 static void st7735r_shutdown(struct spi_device *spi)
227 {
228 	drm_atomic_helper_shutdown(spi_get_drvdata(spi));
229 }
230 
231 static struct spi_driver st7735r_spi_driver = {
232 	.driver = {
233 		.name = "st7735r",
234 		.owner = THIS_MODULE,
235 		.of_match_table = st7735r_of_match,
236 	},
237 	.id_table = st7735r_id,
238 	.probe = st7735r_probe,
239 	.remove = st7735r_remove,
240 	.shutdown = st7735r_shutdown,
241 };
242 module_spi_driver(st7735r_spi_driver);
243 
244 MODULE_DESCRIPTION("Sitronix ST7735R DRM driver");
245 MODULE_AUTHOR("David Lechner <david@lechnology.com>");
246 MODULE_LICENSE("GPL");
247