xref: /openbmc/linux/drivers/gpu/drm/tiny/st7735r.c (revision 28dce2c4)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * DRM driver for display panels connected to a Sitronix ST7715R or ST7735R
4  * display controller in SPI mode.
5  *
6  * Copyright 2017 David Lechner <david@lechnology.com>
7  * Copyright (C) 2019 Glider bvba
8  */
9 
10 #include <linux/backlight.h>
11 #include <linux/delay.h>
12 #include <linux/dma-buf.h>
13 #include <linux/gpio/consumer.h>
14 #include <linux/module.h>
15 #include <linux/property.h>
16 #include <linux/spi/spi.h>
17 #include <video/mipi_display.h>
18 
19 #include <drm/drm_atomic_helper.h>
20 #include <drm/drm_drv.h>
21 #include <drm/drm_fb_helper.h>
22 #include <drm/drm_gem_atomic_helper.h>
23 #include <drm/drm_gem_cma_helper.h>
24 #include <drm/drm_managed.h>
25 #include <drm/drm_mipi_dbi.h>
26 
27 #define ST7735R_FRMCTR1		0xb1
28 #define ST7735R_FRMCTR2		0xb2
29 #define ST7735R_FRMCTR3		0xb3
30 #define ST7735R_INVCTR		0xb4
31 #define ST7735R_PWCTR1		0xc0
32 #define ST7735R_PWCTR2		0xc1
33 #define ST7735R_PWCTR3		0xc2
34 #define ST7735R_PWCTR4		0xc3
35 #define ST7735R_PWCTR5		0xc4
36 #define ST7735R_VMCTR1		0xc5
37 #define ST7735R_GAMCTRP1	0xe0
38 #define ST7735R_GAMCTRN1	0xe1
39 
40 #define ST7735R_MY	BIT(7)
41 #define ST7735R_MX	BIT(6)
42 #define ST7735R_MV	BIT(5)
43 #define ST7735R_RGB	BIT(3)
44 
45 struct st7735r_cfg {
46 	const struct drm_display_mode mode;
47 	unsigned int left_offset;
48 	unsigned int top_offset;
49 	unsigned int write_only:1;
50 	unsigned int rgb:1;		/* RGB (vs. BGR) */
51 };
52 
53 struct st7735r_priv {
54 	struct mipi_dbi_dev dbidev;	/* Must be first for .release() */
55 	const struct st7735r_cfg *cfg;
56 };
57 
58 static void st7735r_pipe_enable(struct drm_simple_display_pipe *pipe,
59 				struct drm_crtc_state *crtc_state,
60 				struct drm_plane_state *plane_state)
61 {
62 	struct mipi_dbi_dev *dbidev = drm_to_mipi_dbi_dev(pipe->crtc.dev);
63 	struct st7735r_priv *priv = container_of(dbidev, struct st7735r_priv,
64 						 dbidev);
65 	struct mipi_dbi *dbi = &dbidev->dbi;
66 	int ret, idx;
67 	u8 addr_mode;
68 
69 	if (!drm_dev_enter(pipe->crtc.dev, &idx))
70 		return;
71 
72 	DRM_DEBUG_KMS("\n");
73 
74 	ret = mipi_dbi_poweron_reset(dbidev);
75 	if (ret)
76 		goto out_exit;
77 
78 	msleep(150);
79 
80 	mipi_dbi_command(dbi, MIPI_DCS_EXIT_SLEEP_MODE);
81 	msleep(500);
82 
83 	mipi_dbi_command(dbi, ST7735R_FRMCTR1, 0x01, 0x2c, 0x2d);
84 	mipi_dbi_command(dbi, ST7735R_FRMCTR2, 0x01, 0x2c, 0x2d);
85 	mipi_dbi_command(dbi, ST7735R_FRMCTR3, 0x01, 0x2c, 0x2d, 0x01, 0x2c,
86 			 0x2d);
87 	mipi_dbi_command(dbi, ST7735R_INVCTR, 0x07);
88 	mipi_dbi_command(dbi, ST7735R_PWCTR1, 0xa2, 0x02, 0x84);
89 	mipi_dbi_command(dbi, ST7735R_PWCTR2, 0xc5);
90 	mipi_dbi_command(dbi, ST7735R_PWCTR3, 0x0a, 0x00);
91 	mipi_dbi_command(dbi, ST7735R_PWCTR4, 0x8a, 0x2a);
92 	mipi_dbi_command(dbi, ST7735R_PWCTR5, 0x8a, 0xee);
93 	mipi_dbi_command(dbi, ST7735R_VMCTR1, 0x0e);
94 	mipi_dbi_command(dbi, MIPI_DCS_EXIT_INVERT_MODE);
95 	switch (dbidev->rotation) {
96 	default:
97 		addr_mode = ST7735R_MX | ST7735R_MY;
98 		break;
99 	case 90:
100 		addr_mode = ST7735R_MX | ST7735R_MV;
101 		break;
102 	case 180:
103 		addr_mode = 0;
104 		break;
105 	case 270:
106 		addr_mode = ST7735R_MY | ST7735R_MV;
107 		break;
108 	}
109 
110 	if (priv->cfg->rgb)
111 		addr_mode |= ST7735R_RGB;
112 
113 	mipi_dbi_command(dbi, MIPI_DCS_SET_ADDRESS_MODE, addr_mode);
114 	mipi_dbi_command(dbi, MIPI_DCS_SET_PIXEL_FORMAT,
115 			 MIPI_DCS_PIXEL_FMT_16BIT);
116 	mipi_dbi_command(dbi, ST7735R_GAMCTRP1, 0x02, 0x1c, 0x07, 0x12, 0x37,
117 			 0x32, 0x29, 0x2d, 0x29, 0x25, 0x2b, 0x39, 0x00, 0x01,
118 			 0x03, 0x10);
119 	mipi_dbi_command(dbi, ST7735R_GAMCTRN1, 0x03, 0x1d, 0x07, 0x06, 0x2e,
120 			 0x2c, 0x29, 0x2d, 0x2e, 0x2e, 0x37, 0x3f, 0x00, 0x00,
121 			 0x02, 0x10);
122 	mipi_dbi_command(dbi, MIPI_DCS_SET_DISPLAY_ON);
123 
124 	msleep(100);
125 
126 	mipi_dbi_command(dbi, MIPI_DCS_ENTER_NORMAL_MODE);
127 
128 	msleep(20);
129 
130 	mipi_dbi_enable_flush(dbidev, crtc_state, plane_state);
131 out_exit:
132 	drm_dev_exit(idx);
133 }
134 
135 static const struct drm_simple_display_pipe_funcs st7735r_pipe_funcs = {
136 	.enable		= st7735r_pipe_enable,
137 	.disable	= mipi_dbi_pipe_disable,
138 	.update		= mipi_dbi_pipe_update,
139 	.prepare_fb	= drm_gem_simple_display_pipe_prepare_fb,
140 };
141 
142 static const struct st7735r_cfg jd_t18003_t01_cfg = {
143 	.mode		= { DRM_SIMPLE_MODE(128, 160, 28, 35) },
144 	/* Cannot read from Adafruit 1.8" display via SPI */
145 	.write_only	= true,
146 };
147 
148 static const struct st7735r_cfg rh128128t_cfg = {
149 	.mode		= { DRM_SIMPLE_MODE(128, 128, 25, 26) },
150 	.left_offset	= 2,
151 	.top_offset	= 3,
152 	.rgb		= true,
153 };
154 
155 DEFINE_DRM_GEM_CMA_FOPS(st7735r_fops);
156 
157 static const struct drm_driver st7735r_driver = {
158 	.driver_features	= DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC,
159 	.fops			= &st7735r_fops,
160 	DRM_GEM_CMA_DRIVER_OPS_VMAP,
161 	.debugfs_init		= mipi_dbi_debugfs_init,
162 	.name			= "st7735r",
163 	.desc			= "Sitronix ST7735R",
164 	.date			= "20171128",
165 	.major			= 1,
166 	.minor			= 0,
167 };
168 
169 static const struct of_device_id st7735r_of_match[] = {
170 	{ .compatible = "jianda,jd-t18003-t01", .data = &jd_t18003_t01_cfg },
171 	{ .compatible = "okaya,rh128128t", .data = &rh128128t_cfg },
172 	{ },
173 };
174 MODULE_DEVICE_TABLE(of, st7735r_of_match);
175 
176 static const struct spi_device_id st7735r_id[] = {
177 	{ "jd-t18003-t01", (uintptr_t)&jd_t18003_t01_cfg },
178 	{ },
179 };
180 MODULE_DEVICE_TABLE(spi, st7735r_id);
181 
182 static int st7735r_probe(struct spi_device *spi)
183 {
184 	struct device *dev = &spi->dev;
185 	const struct st7735r_cfg *cfg;
186 	struct mipi_dbi_dev *dbidev;
187 	struct st7735r_priv *priv;
188 	struct drm_device *drm;
189 	struct mipi_dbi *dbi;
190 	struct gpio_desc *dc;
191 	u32 rotation = 0;
192 	int ret;
193 
194 	cfg = device_get_match_data(&spi->dev);
195 	if (!cfg)
196 		cfg = (void *)spi_get_device_id(spi)->driver_data;
197 
198 	priv = devm_drm_dev_alloc(dev, &st7735r_driver,
199 				  struct st7735r_priv, dbidev.drm);
200 	if (IS_ERR(priv))
201 		return PTR_ERR(priv);
202 
203 	dbidev = &priv->dbidev;
204 	priv->cfg = cfg;
205 
206 	dbi = &dbidev->dbi;
207 	drm = &dbidev->drm;
208 
209 	dbi->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
210 	if (IS_ERR(dbi->reset)) {
211 		DRM_DEV_ERROR(dev, "Failed to get gpio 'reset'\n");
212 		return PTR_ERR(dbi->reset);
213 	}
214 
215 	dc = devm_gpiod_get(dev, "dc", GPIOD_OUT_LOW);
216 	if (IS_ERR(dc)) {
217 		DRM_DEV_ERROR(dev, "Failed to get gpio 'dc'\n");
218 		return PTR_ERR(dc);
219 	}
220 
221 	dbidev->backlight = devm_of_find_backlight(dev);
222 	if (IS_ERR(dbidev->backlight))
223 		return PTR_ERR(dbidev->backlight);
224 
225 	device_property_read_u32(dev, "rotation", &rotation);
226 
227 	ret = mipi_dbi_spi_init(spi, dbi, dc);
228 	if (ret)
229 		return ret;
230 
231 	if (cfg->write_only)
232 		dbi->read_commands = NULL;
233 
234 	dbidev->left_offset = cfg->left_offset;
235 	dbidev->top_offset = cfg->top_offset;
236 
237 	ret = mipi_dbi_dev_init(dbidev, &st7735r_pipe_funcs, &cfg->mode,
238 				rotation);
239 	if (ret)
240 		return ret;
241 
242 	drm_mode_config_reset(drm);
243 
244 	ret = drm_dev_register(drm, 0);
245 	if (ret)
246 		return ret;
247 
248 	spi_set_drvdata(spi, drm);
249 
250 	drm_fbdev_generic_setup(drm, 0);
251 
252 	return 0;
253 }
254 
255 static int st7735r_remove(struct spi_device *spi)
256 {
257 	struct drm_device *drm = spi_get_drvdata(spi);
258 
259 	drm_dev_unplug(drm);
260 	drm_atomic_helper_shutdown(drm);
261 
262 	return 0;
263 }
264 
265 static void st7735r_shutdown(struct spi_device *spi)
266 {
267 	drm_atomic_helper_shutdown(spi_get_drvdata(spi));
268 }
269 
270 static struct spi_driver st7735r_spi_driver = {
271 	.driver = {
272 		.name = "st7735r",
273 		.of_match_table = st7735r_of_match,
274 	},
275 	.id_table = st7735r_id,
276 	.probe = st7735r_probe,
277 	.remove = st7735r_remove,
278 	.shutdown = st7735r_shutdown,
279 };
280 module_spi_driver(st7735r_spi_driver);
281 
282 MODULE_DESCRIPTION("Sitronix ST7735R DRM driver");
283 MODULE_AUTHOR("David Lechner <david@lechnology.com>");
284 MODULE_LICENSE("GPL");
285