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