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 }; 140 141 static const struct st7735r_cfg jd_t18003_t01_cfg = { 142 .mode = { DRM_SIMPLE_MODE(128, 160, 28, 35) }, 143 /* Cannot read from Adafruit 1.8" display via SPI */ 144 .write_only = true, 145 }; 146 147 static const struct st7735r_cfg rh128128t_cfg = { 148 .mode = { DRM_SIMPLE_MODE(128, 128, 25, 26) }, 149 .left_offset = 2, 150 .top_offset = 3, 151 .rgb = true, 152 }; 153 154 DEFINE_DRM_GEM_CMA_FOPS(st7735r_fops); 155 156 static const struct drm_driver st7735r_driver = { 157 .driver_features = DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC, 158 .fops = &st7735r_fops, 159 DRM_GEM_CMA_DRIVER_OPS_VMAP, 160 .debugfs_init = mipi_dbi_debugfs_init, 161 .name = "st7735r", 162 .desc = "Sitronix ST7735R", 163 .date = "20171128", 164 .major = 1, 165 .minor = 0, 166 }; 167 168 static const struct of_device_id st7735r_of_match[] = { 169 { .compatible = "jianda,jd-t18003-t01", .data = &jd_t18003_t01_cfg }, 170 { .compatible = "okaya,rh128128t", .data = &rh128128t_cfg }, 171 { }, 172 }; 173 MODULE_DEVICE_TABLE(of, st7735r_of_match); 174 175 static const struct spi_device_id st7735r_id[] = { 176 { "jd-t18003-t01", (uintptr_t)&jd_t18003_t01_cfg }, 177 { }, 178 }; 179 MODULE_DEVICE_TABLE(spi, st7735r_id); 180 181 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_fbdev_generic_setup(drm, 0); 246 247 return 0; 248 } 249 250 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 } 257 258 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