1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * DRM driver for Ilitek ILI9486 panels 4 * 5 * Copyright 2020 Kamlesh Gurudasani <kamlesh.gurudasani@gmail.com> 6 */ 7 8 #include <linux/backlight.h> 9 #include <linux/delay.h> 10 #include <linux/gpio/consumer.h> 11 #include <linux/module.h> 12 #include <linux/property.h> 13 #include <linux/spi/spi.h> 14 15 #include <video/mipi_display.h> 16 17 #include <drm/clients/drm_client_setup.h> 18 #include <drm/drm_atomic_helper.h> 19 #include <drm/drm_drv.h> 20 #include <drm/drm_fbdev_dma.h> 21 #include <drm/drm_gem_atomic_helper.h> 22 #include <drm/drm_gem_dma_helper.h> 23 #include <drm/drm_managed.h> 24 #include <drm/drm_mipi_dbi.h> 25 #include <drm/drm_modeset_helper.h> 26 #include <drm/drm_print.h> 27 28 #define ILI9486_ITFCTR1 0xb0 29 #define ILI9486_PWCTRL1 0xc2 30 #define ILI9486_VMCTRL1 0xc5 31 #define ILI9486_PGAMCTRL 0xe0 32 #define ILI9486_NGAMCTRL 0xe1 33 #define ILI9486_DGAMCTRL 0xe2 34 #define ILI9486_MADCTL_BGR BIT(3) 35 #define ILI9486_MADCTL_MV BIT(5) 36 #define ILI9486_MADCTL_MX BIT(6) 37 #define ILI9486_MADCTL_MY BIT(7) 38 39 struct ili9486_device { 40 struct mipi_dbi_dev dbidev; 41 42 struct drm_plane plane; 43 struct drm_crtc crtc; 44 struct drm_encoder encoder; 45 struct drm_connector connector; 46 }; 47 48 static struct ili9486_device *to_ili9486_device(struct drm_device *dev) 49 { 50 return container_of(drm_to_mipi_dbi_dev(dev), struct ili9486_device, dbidev); 51 } 52 53 /* 54 * The PiScreen/waveshare rpi-lcd-35 has a SPI to 16-bit parallel bus converter 55 * in front of the display controller. This means that 8-bit values have to be 56 * transferred as 16-bit. 57 */ 58 static int waveshare_command(struct mipi_dbi *mipi, u8 *cmd, u8 *par, 59 size_t num) 60 { 61 struct spi_device *spi = mipi->spi; 62 unsigned int bpw = 8; 63 void *data = par; 64 u32 speed_hz; 65 int i, ret; 66 __be16 *buf; 67 68 buf = kmalloc(32 * sizeof(u16), GFP_KERNEL); 69 if (!buf) 70 return -ENOMEM; 71 72 /* 73 * The displays are Raspberry Pi HATs and connected to the 8-bit only 74 * SPI controller, so 16-bit command and parameters need byte swapping 75 * before being transferred as 8-bit on the big endian SPI bus. 76 */ 77 buf[0] = cpu_to_be16(*cmd); 78 spi_bus_lock(spi->controller); 79 gpiod_set_value_cansleep(mipi->dc, 0); 80 speed_hz = mipi_dbi_spi_cmd_max_speed(spi, 2); 81 ret = mipi_dbi_spi_transfer(spi, speed_hz, 8, buf, 2); 82 spi_bus_unlock(spi->controller); 83 if (ret || !num) 84 goto free; 85 86 /* 8-bit configuration data, not 16-bit pixel data */ 87 if (num <= 32) { 88 for (i = 0; i < num; i++) 89 buf[i] = cpu_to_be16(par[i]); 90 num *= 2; 91 data = buf; 92 } 93 94 /* 95 * Check whether pixel data bytes needs to be swapped or not 96 */ 97 if (*cmd == MIPI_DCS_WRITE_MEMORY_START && !mipi->swap_bytes) 98 bpw = 16; 99 100 spi_bus_lock(spi->controller); 101 gpiod_set_value_cansleep(mipi->dc, 1); 102 speed_hz = mipi_dbi_spi_cmd_max_speed(spi, num); 103 ret = mipi_dbi_spi_transfer(spi, speed_hz, bpw, data, num); 104 spi_bus_unlock(spi->controller); 105 free: 106 kfree(buf); 107 108 return ret; 109 } 110 111 static const u32 ili9486_plane_formats[] = { 112 DRM_MIPI_DBI_PLANE_FORMATS, 113 }; 114 115 static const u64 ili9486_plane_format_modifiers[] = { 116 DRM_MIPI_DBI_PLANE_FORMAT_MODIFIERS, 117 }; 118 119 static const struct drm_plane_helper_funcs ili9486_plane_helper_funcs = { 120 DRM_MIPI_DBI_PLANE_HELPER_FUNCS, 121 }; 122 123 static const struct drm_plane_funcs ili9486_plane_funcs = { 124 DRM_MIPI_DBI_PLANE_FUNCS, 125 .destroy = drm_plane_cleanup, 126 }; 127 128 static void ili9486_crtc_helper_atomic_enable(struct drm_crtc *crtc, 129 struct drm_atomic_state *state) 130 { 131 struct drm_device *drm = crtc->dev; 132 struct ili9486_device *ili9486 = to_ili9486_device(drm); 133 struct mipi_dbi_dev *dbidev = &ili9486->dbidev; 134 struct mipi_dbi *dbi = &dbidev->dbi; 135 u8 addr_mode; 136 int ret, idx; 137 138 if (!drm_dev_enter(drm, &idx)) 139 return; 140 141 DRM_DEBUG_KMS("\n"); 142 143 ret = mipi_dbi_poweron_conditional_reset(dbidev); 144 if (ret < 0) 145 goto out_exit; 146 if (ret == 1) 147 goto out_enable; 148 149 mipi_dbi_command(dbi, ILI9486_ITFCTR1); 150 mipi_dbi_command(dbi, MIPI_DCS_EXIT_SLEEP_MODE); 151 msleep(250); 152 153 mipi_dbi_command(dbi, MIPI_DCS_SET_PIXEL_FORMAT, 0x55); 154 155 mipi_dbi_command(dbi, ILI9486_PWCTRL1, 0x44); 156 157 mipi_dbi_command(dbi, ILI9486_VMCTRL1, 0x00, 0x00, 0x00, 0x00); 158 159 mipi_dbi_command(dbi, ILI9486_PGAMCTRL, 160 0x0F, 0x1F, 0x1C, 0x0C, 0x0F, 0x08, 0x48, 0x98, 161 0x37, 0x0A, 0x13, 0x04, 0x11, 0x0D, 0x0); 162 mipi_dbi_command(dbi, ILI9486_NGAMCTRL, 163 0x0F, 0x32, 0x2E, 0x0B, 0x0D, 0x05, 0x47, 0x75, 164 0x37, 0x06, 0x10, 0x03, 0x24, 0x20, 0x00); 165 mipi_dbi_command(dbi, ILI9486_DGAMCTRL, 166 0x0F, 0x32, 0x2E, 0x0B, 0x0D, 0x05, 0x47, 0x75, 167 0x37, 0x06, 0x10, 0x03, 0x24, 0x20, 0x00); 168 169 mipi_dbi_command(dbi, MIPI_DCS_SET_DISPLAY_ON); 170 msleep(100); 171 172 out_enable: 173 switch (dbidev->rotation) { 174 case 90: 175 addr_mode = ILI9486_MADCTL_MY; 176 break; 177 case 180: 178 addr_mode = ILI9486_MADCTL_MV; 179 break; 180 case 270: 181 addr_mode = ILI9486_MADCTL_MX; 182 break; 183 default: 184 addr_mode = ILI9486_MADCTL_MV | ILI9486_MADCTL_MY | 185 ILI9486_MADCTL_MX; 186 break; 187 } 188 addr_mode |= ILI9486_MADCTL_BGR; 189 mipi_dbi_command(dbi, MIPI_DCS_SET_ADDRESS_MODE, addr_mode); 190 191 backlight_enable(dbidev->backlight); 192 out_exit: 193 drm_dev_exit(idx); 194 } 195 196 static const struct drm_crtc_helper_funcs ili9486_crtc_helper_funcs = { 197 DRM_MIPI_DBI_CRTC_HELPER_FUNCS, 198 .atomic_enable = ili9486_crtc_helper_atomic_enable, 199 }; 200 201 static const struct drm_crtc_funcs ili9486_crtc_funcs = { 202 DRM_MIPI_DBI_CRTC_FUNCS, 203 .destroy = drm_crtc_cleanup, 204 }; 205 206 static const struct drm_encoder_funcs ili9486_encoder_funcs = { 207 .destroy = drm_encoder_cleanup, 208 }; 209 210 static const struct drm_connector_helper_funcs ili9486_connector_helper_funcs = { 211 DRM_MIPI_DBI_CONNECTOR_HELPER_FUNCS, 212 }; 213 214 static const struct drm_connector_funcs ili9486_connector_funcs = { 215 DRM_MIPI_DBI_CONNECTOR_FUNCS, 216 .destroy = drm_connector_cleanup, 217 }; 218 219 static const struct drm_mode_config_helper_funcs ili9486_mode_config_helper_funcs = { 220 DRM_MIPI_DBI_MODE_CONFIG_HELPER_FUNCS, 221 }; 222 223 static const struct drm_mode_config_funcs ili9486_mode_config_funcs = { 224 DRM_MIPI_DBI_MODE_CONFIG_FUNCS, 225 }; 226 227 static const struct drm_display_mode waveshare_mode = { 228 DRM_SIMPLE_MODE(480, 320, 73, 49), 229 }; 230 231 DEFINE_DRM_GEM_DMA_FOPS(ili9486_fops); 232 233 static const struct drm_driver ili9486_driver = { 234 .driver_features = DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC, 235 .fops = &ili9486_fops, 236 DRM_GEM_DMA_DRIVER_OPS_VMAP, 237 DRM_FBDEV_DMA_DRIVER_OPS, 238 .debugfs_init = mipi_dbi_debugfs_init, 239 .name = "ili9486", 240 .desc = "Ilitek ILI9486", 241 .major = 1, 242 .minor = 0, 243 }; 244 245 static const struct of_device_id ili9486_of_match[] = { 246 { .compatible = "waveshare,rpi-lcd-35" }, 247 { .compatible = "ozzmaker,piscreen" }, 248 {}, 249 }; 250 MODULE_DEVICE_TABLE(of, ili9486_of_match); 251 252 static const struct spi_device_id ili9486_id[] = { 253 { "ili9486", 0 }, 254 { "rpi-lcd-35", 0 }, 255 { "piscreen", 0 }, 256 { } 257 }; 258 MODULE_DEVICE_TABLE(spi, ili9486_id); 259 260 static int ili9486_probe(struct spi_device *spi) 261 { 262 struct device *dev = &spi->dev; 263 struct ili9486_device *ili9486; 264 struct mipi_dbi_dev *dbidev; 265 struct drm_device *drm; 266 struct mipi_dbi *dbi; 267 struct gpio_desc *dc; 268 struct drm_plane *plane; 269 struct drm_crtc *crtc; 270 struct drm_encoder *encoder; 271 struct drm_connector *connector; 272 u32 rotation = 0; 273 int ret; 274 275 ili9486 = devm_drm_dev_alloc(dev, &ili9486_driver, struct ili9486_device, dbidev.drm); 276 if (IS_ERR(ili9486)) 277 return PTR_ERR(ili9486); 278 dbidev = &ili9486->dbidev; 279 dbi = &dbidev->dbi; 280 drm = &dbidev->drm; 281 282 dbi->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH); 283 if (IS_ERR(dbi->reset)) 284 return dev_err_probe(dev, PTR_ERR(dbi->reset), "Failed to get GPIO 'reset'\n"); 285 286 dc = devm_gpiod_get(dev, "dc", GPIOD_OUT_LOW); 287 if (IS_ERR(dc)) 288 return dev_err_probe(dev, PTR_ERR(dc), "Failed to get GPIO 'dc'\n"); 289 290 dbidev->backlight = devm_of_find_backlight(dev); 291 if (IS_ERR(dbidev->backlight)) 292 return PTR_ERR(dbidev->backlight); 293 294 device_property_read_u32(dev, "rotation", &rotation); 295 296 ret = mipi_dbi_spi_init(spi, dbi, dc); 297 if (ret) 298 return ret; 299 300 dbi->command = waveshare_command; 301 dbi->read_commands = NULL; 302 303 ret = drm_mipi_dbi_dev_init(dbidev, &waveshare_mode, ili9486_plane_formats[0], 304 rotation, 0); 305 if (ret) 306 return ret; 307 308 ret = drmm_mode_config_init(drm); 309 if (ret) 310 return ret; 311 312 drm->mode_config.min_width = dbidev->mode.hdisplay; 313 drm->mode_config.max_width = dbidev->mode.hdisplay; 314 drm->mode_config.min_height = dbidev->mode.vdisplay; 315 drm->mode_config.max_height = dbidev->mode.vdisplay; 316 drm->mode_config.funcs = &ili9486_mode_config_funcs; 317 drm->mode_config.preferred_depth = 16; 318 drm->mode_config.helper_private = &ili9486_mode_config_helper_funcs; 319 320 plane = &ili9486->plane; 321 ret = drm_universal_plane_init(drm, plane, 0, &ili9486_plane_funcs, 322 ili9486_plane_formats, ARRAY_SIZE(ili9486_plane_formats), 323 ili9486_plane_format_modifiers, 324 DRM_PLANE_TYPE_PRIMARY, NULL); 325 if (ret) 326 return ret; 327 drm_plane_helper_add(plane, &ili9486_plane_helper_funcs); 328 drm_plane_enable_fb_damage_clips(plane); 329 330 crtc = &ili9486->crtc; 331 ret = drm_crtc_init_with_planes(drm, crtc, plane, NULL, &ili9486_crtc_funcs, NULL); 332 if (ret) 333 return ret; 334 drm_crtc_helper_add(crtc, &ili9486_crtc_helper_funcs); 335 336 encoder = &ili9486->encoder; 337 ret = drm_encoder_init(drm, encoder, &ili9486_encoder_funcs, DRM_MODE_ENCODER_NONE, NULL); 338 if (ret) 339 return ret; 340 encoder->possible_crtcs = drm_crtc_mask(crtc); 341 342 connector = &ili9486->connector; 343 ret = drm_connector_init(drm, connector, &ili9486_connector_funcs, 344 DRM_MODE_CONNECTOR_SPI); 345 if (ret) 346 return ret; 347 drm_connector_helper_add(connector, &ili9486_connector_helper_funcs); 348 349 ret = drm_connector_attach_encoder(connector, encoder); 350 if (ret) 351 return ret; 352 353 drm_mode_config_reset(drm); 354 355 ret = drm_dev_register(drm, 0); 356 if (ret) 357 return ret; 358 359 spi_set_drvdata(spi, drm); 360 361 drm_client_setup(drm, NULL); 362 363 return 0; 364 } 365 366 static void ili9486_remove(struct spi_device *spi) 367 { 368 struct drm_device *drm = spi_get_drvdata(spi); 369 370 drm_dev_unplug(drm); 371 drm_atomic_helper_shutdown(drm); 372 } 373 374 static void ili9486_shutdown(struct spi_device *spi) 375 { 376 drm_atomic_helper_shutdown(spi_get_drvdata(spi)); 377 } 378 379 static struct spi_driver ili9486_spi_driver = { 380 .driver = { 381 .name = "ili9486", 382 .of_match_table = ili9486_of_match, 383 }, 384 .id_table = ili9486_id, 385 .probe = ili9486_probe, 386 .remove = ili9486_remove, 387 .shutdown = ili9486_shutdown, 388 }; 389 module_spi_driver(ili9486_spi_driver); 390 391 MODULE_DESCRIPTION("Ilitek ILI9486 DRM driver"); 392 MODULE_AUTHOR("Kamlesh Gurudasani <kamlesh.gurudasani@gmail.com>"); 393 MODULE_LICENSE("GPL"); 394