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_fbdev_generic.h>
22 #include <drm/drm_gem_atomic_helper.h>
23 #include <drm/drm_gem_dma_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
st7735r_pipe_enable(struct drm_simple_display_pipe * pipe,struct drm_crtc_state * crtc_state,struct drm_plane_state * plane_state)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 DRM_MIPI_DBI_SIMPLE_DISPLAY_PIPE_FUNCS(st7735r_pipe_enable),
137 };
138
139 static const struct st7735r_cfg jd_t18003_t01_cfg = {
140 .mode = { DRM_SIMPLE_MODE(128, 160, 28, 35) },
141 /* Cannot read from Adafruit 1.8" display via SPI */
142 .write_only = true,
143 };
144
145 static const struct st7735r_cfg rh128128t_cfg = {
146 .mode = { DRM_SIMPLE_MODE(128, 128, 25, 26) },
147 .left_offset = 2,
148 .top_offset = 3,
149 .rgb = true,
150 };
151
152 DEFINE_DRM_GEM_DMA_FOPS(st7735r_fops);
153
154 static const struct drm_driver st7735r_driver = {
155 .driver_features = DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC,
156 .fops = &st7735r_fops,
157 DRM_GEM_DMA_DRIVER_OPS_VMAP,
158 .debugfs_init = mipi_dbi_debugfs_init,
159 .name = "st7735r",
160 .desc = "Sitronix ST7735R",
161 .date = "20171128",
162 .major = 1,
163 .minor = 0,
164 };
165
166 static const struct of_device_id st7735r_of_match[] = {
167 { .compatible = "jianda,jd-t18003-t01", .data = &jd_t18003_t01_cfg },
168 { .compatible = "okaya,rh128128t", .data = &rh128128t_cfg },
169 { },
170 };
171 MODULE_DEVICE_TABLE(of, st7735r_of_match);
172
173 static const struct spi_device_id st7735r_id[] = {
174 { "jd-t18003-t01", (uintptr_t)&jd_t18003_t01_cfg },
175 { "rh128128t", (uintptr_t)&rh128128t_cfg },
176 { },
177 };
178 MODULE_DEVICE_TABLE(spi, st7735r_id);
179
st7735r_probe(struct spi_device * spi)180 static int st7735r_probe(struct spi_device *spi)
181 {
182 struct device *dev = &spi->dev;
183 const struct st7735r_cfg *cfg;
184 struct mipi_dbi_dev *dbidev;
185 struct st7735r_priv *priv;
186 struct drm_device *drm;
187 struct mipi_dbi *dbi;
188 struct gpio_desc *dc;
189 u32 rotation = 0;
190 int ret;
191
192 cfg = device_get_match_data(&spi->dev);
193 if (!cfg)
194 cfg = (void *)spi_get_device_id(spi)->driver_data;
195
196 priv = devm_drm_dev_alloc(dev, &st7735r_driver,
197 struct st7735r_priv, dbidev.drm);
198 if (IS_ERR(priv))
199 return PTR_ERR(priv);
200
201 dbidev = &priv->dbidev;
202 priv->cfg = cfg;
203
204 dbi = &dbidev->dbi;
205 drm = &dbidev->drm;
206
207 dbi->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
208 if (IS_ERR(dbi->reset))
209 return dev_err_probe(dev, PTR_ERR(dbi->reset), "Failed to get GPIO 'reset'\n");
210
211 dc = devm_gpiod_get(dev, "dc", GPIOD_OUT_LOW);
212 if (IS_ERR(dc))
213 return dev_err_probe(dev, PTR_ERR(dc), "Failed to get GPIO 'dc'\n");
214
215 dbidev->backlight = devm_of_find_backlight(dev);
216 if (IS_ERR(dbidev->backlight))
217 return PTR_ERR(dbidev->backlight);
218
219 device_property_read_u32(dev, "rotation", &rotation);
220
221 ret = mipi_dbi_spi_init(spi, dbi, dc);
222 if (ret)
223 return ret;
224
225 if (cfg->write_only)
226 dbi->read_commands = NULL;
227
228 dbidev->left_offset = cfg->left_offset;
229 dbidev->top_offset = cfg->top_offset;
230
231 ret = mipi_dbi_dev_init(dbidev, &st7735r_pipe_funcs, &cfg->mode,
232 rotation);
233 if (ret)
234 return ret;
235
236 drm_mode_config_reset(drm);
237
238 ret = drm_dev_register(drm, 0);
239 if (ret)
240 return ret;
241
242 spi_set_drvdata(spi, drm);
243
244 drm_fbdev_generic_setup(drm, 0);
245
246 return 0;
247 }
248
st7735r_remove(struct spi_device * spi)249 static void st7735r_remove(struct spi_device *spi)
250 {
251 struct drm_device *drm = spi_get_drvdata(spi);
252
253 drm_dev_unplug(drm);
254 drm_atomic_helper_shutdown(drm);
255 }
256
st7735r_shutdown(struct spi_device * spi)257 static void st7735r_shutdown(struct spi_device *spi)
258 {
259 drm_atomic_helper_shutdown(spi_get_drvdata(spi));
260 }
261
262 static struct spi_driver st7735r_spi_driver = {
263 .driver = {
264 .name = "st7735r",
265 .of_match_table = st7735r_of_match,
266 },
267 .id_table = st7735r_id,
268 .probe = st7735r_probe,
269 .remove = st7735r_remove,
270 .shutdown = st7735r_shutdown,
271 };
272 module_spi_driver(st7735r_spi_driver);
273
274 MODULE_DESCRIPTION("Sitronix ST7735R DRM driver");
275 MODULE_AUTHOR("David Lechner <david@lechnology.com>");
276 MODULE_LICENSE("GPL");
277