1 /* 2 * Copyright © 2016-2017 Broadcom 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License version 2 as 6 * published by the Free Software Foundation. 7 * 8 * Portions of this file (derived from panel-simple.c) are: 9 * 10 * Copyright (C) 2013, NVIDIA Corporation. All rights reserved. 11 * 12 * Permission is hereby granted, free of charge, to any person obtaining a 13 * copy of this software and associated documentation files (the "Software"), 14 * to deal in the Software without restriction, including without limitation 15 * the rights to use, copy, modify, merge, publish, distribute, sub license, 16 * and/or sell copies of the Software, and to permit persons to whom the 17 * Software is furnished to do so, subject to the following conditions: 18 * 19 * The above copyright notice and this permission notice (including the 20 * next paragraph) shall be included in all copies or substantial portions 21 * of the Software. 22 * 23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 24 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 25 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL 26 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 27 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 28 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 29 * DEALINGS IN THE SOFTWARE. 30 */ 31 32 /* 33 * Raspberry Pi 7" touchscreen panel driver. 34 * 35 * The 7" touchscreen consists of a DPI LCD panel, a Toshiba 36 * TC358762XBG DSI-DPI bridge, and an I2C-connected Atmel ATTINY88-MUR 37 * controlling power management, the LCD PWM, and initial register 38 * setup of the Tohsiba. 39 * 40 * This driver controls the TC358762 and ATTINY88, presenting a DSI 41 * device with a drm_panel. 42 */ 43 44 #include <linux/delay.h> 45 #include <linux/err.h> 46 #include <linux/i2c.h> 47 #include <linux/media-bus-format.h> 48 #include <linux/module.h> 49 #include <linux/of.h> 50 #include <linux/of_device.h> 51 #include <linux/of_graph.h> 52 #include <linux/pm.h> 53 54 #include <drm/drm_crtc.h> 55 #include <drm/drm_device.h> 56 #include <drm/drm_mipi_dsi.h> 57 #include <drm/drm_panel.h> 58 59 #define RPI_DSI_DRIVER_NAME "rpi-ts-dsi" 60 61 /* I2C registers of the Atmel microcontroller. */ 62 enum REG_ADDR { 63 REG_ID = 0x80, 64 REG_PORTA, /* BIT(2) for horizontal flip, BIT(3) for vertical flip */ 65 REG_PORTB, 66 REG_PORTC, 67 REG_PORTD, 68 REG_POWERON, 69 REG_PWM, 70 REG_DDRA, 71 REG_DDRB, 72 REG_DDRC, 73 REG_DDRD, 74 REG_TEST, 75 REG_WR_ADDRL, 76 REG_WR_ADDRH, 77 REG_READH, 78 REG_READL, 79 REG_WRITEH, 80 REG_WRITEL, 81 REG_ID2, 82 }; 83 84 /* DSI D-PHY Layer Registers */ 85 #define D0W_DPHYCONTTX 0x0004 86 #define CLW_DPHYCONTRX 0x0020 87 #define D0W_DPHYCONTRX 0x0024 88 #define D1W_DPHYCONTRX 0x0028 89 #define COM_DPHYCONTRX 0x0038 90 #define CLW_CNTRL 0x0040 91 #define D0W_CNTRL 0x0044 92 #define D1W_CNTRL 0x0048 93 #define DFTMODE_CNTRL 0x0054 94 95 /* DSI PPI Layer Registers */ 96 #define PPI_STARTPPI 0x0104 97 #define PPI_BUSYPPI 0x0108 98 #define PPI_LINEINITCNT 0x0110 99 #define PPI_LPTXTIMECNT 0x0114 100 #define PPI_CLS_ATMR 0x0140 101 #define PPI_D0S_ATMR 0x0144 102 #define PPI_D1S_ATMR 0x0148 103 #define PPI_D0S_CLRSIPOCOUNT 0x0164 104 #define PPI_D1S_CLRSIPOCOUNT 0x0168 105 #define CLS_PRE 0x0180 106 #define D0S_PRE 0x0184 107 #define D1S_PRE 0x0188 108 #define CLS_PREP 0x01A0 109 #define D0S_PREP 0x01A4 110 #define D1S_PREP 0x01A8 111 #define CLS_ZERO 0x01C0 112 #define D0S_ZERO 0x01C4 113 #define D1S_ZERO 0x01C8 114 #define PPI_CLRFLG 0x01E0 115 #define PPI_CLRSIPO 0x01E4 116 #define HSTIMEOUT 0x01F0 117 #define HSTIMEOUTENABLE 0x01F4 118 119 /* DSI Protocol Layer Registers */ 120 #define DSI_STARTDSI 0x0204 121 #define DSI_BUSYDSI 0x0208 122 #define DSI_LANEENABLE 0x0210 123 # define DSI_LANEENABLE_CLOCK BIT(0) 124 # define DSI_LANEENABLE_D0 BIT(1) 125 # define DSI_LANEENABLE_D1 BIT(2) 126 127 #define DSI_LANESTATUS0 0x0214 128 #define DSI_LANESTATUS1 0x0218 129 #define DSI_INTSTATUS 0x0220 130 #define DSI_INTMASK 0x0224 131 #define DSI_INTCLR 0x0228 132 #define DSI_LPTXTO 0x0230 133 #define DSI_MODE 0x0260 134 #define DSI_PAYLOAD0 0x0268 135 #define DSI_PAYLOAD1 0x026C 136 #define DSI_SHORTPKTDAT 0x0270 137 #define DSI_SHORTPKTREQ 0x0274 138 #define DSI_BTASTA 0x0278 139 #define DSI_BTACLR 0x027C 140 141 /* DSI General Registers */ 142 #define DSIERRCNT 0x0300 143 #define DSISIGMOD 0x0304 144 145 /* DSI Application Layer Registers */ 146 #define APLCTRL 0x0400 147 #define APLSTAT 0x0404 148 #define APLERR 0x0408 149 #define PWRMOD 0x040C 150 #define RDPKTLN 0x0410 151 #define PXLFMT 0x0414 152 #define MEMWRCMD 0x0418 153 154 /* LCDC/DPI Host Registers */ 155 #define LCDCTRL 0x0420 156 #define HSR 0x0424 157 #define HDISPR 0x0428 158 #define VSR 0x042C 159 #define VDISPR 0x0430 160 #define VFUEN 0x0434 161 162 /* DBI-B Host Registers */ 163 #define DBIBCTRL 0x0440 164 165 /* SPI Master Registers */ 166 #define SPICMR 0x0450 167 #define SPITCR 0x0454 168 169 /* System Controller Registers */ 170 #define SYSSTAT 0x0460 171 #define SYSCTRL 0x0464 172 #define SYSPLL1 0x0468 173 #define SYSPLL2 0x046C 174 #define SYSPLL3 0x0470 175 #define SYSPMCTRL 0x047C 176 177 /* GPIO Registers */ 178 #define GPIOC 0x0480 179 #define GPIOO 0x0484 180 #define GPIOI 0x0488 181 182 /* I2C Registers */ 183 #define I2CCLKCTRL 0x0490 184 185 /* Chip/Rev Registers */ 186 #define IDREG 0x04A0 187 188 /* Debug Registers */ 189 #define WCMDQUEUE 0x0500 190 #define RCMDQUEUE 0x0504 191 192 struct rpi_touchscreen { 193 struct drm_panel base; 194 struct mipi_dsi_device *dsi; 195 struct i2c_client *i2c; 196 }; 197 198 static const struct drm_display_mode rpi_touchscreen_modes[] = { 199 { 200 /* Modeline comes from the Raspberry Pi firmware, with HFP=1 201 * plugged in and clock re-computed from that. 202 */ 203 .clock = 25979400 / 1000, 204 .hdisplay = 800, 205 .hsync_start = 800 + 1, 206 .hsync_end = 800 + 1 + 2, 207 .htotal = 800 + 1 + 2 + 46, 208 .vdisplay = 480, 209 .vsync_start = 480 + 7, 210 .vsync_end = 480 + 7 + 2, 211 .vtotal = 480 + 7 + 2 + 21, 212 }, 213 }; 214 215 static struct rpi_touchscreen *panel_to_ts(struct drm_panel *panel) 216 { 217 return container_of(panel, struct rpi_touchscreen, base); 218 } 219 220 static int rpi_touchscreen_i2c_read(struct rpi_touchscreen *ts, u8 reg) 221 { 222 return i2c_smbus_read_byte_data(ts->i2c, reg); 223 } 224 225 static void rpi_touchscreen_i2c_write(struct rpi_touchscreen *ts, 226 u8 reg, u8 val) 227 { 228 int ret; 229 230 ret = i2c_smbus_write_byte_data(ts->i2c, reg, val); 231 if (ret) 232 dev_err(&ts->i2c->dev, "I2C write failed: %d\n", ret); 233 } 234 235 static int rpi_touchscreen_write(struct rpi_touchscreen *ts, u16 reg, u32 val) 236 { 237 u8 msg[] = { 238 reg, 239 reg >> 8, 240 val, 241 val >> 8, 242 val >> 16, 243 val >> 24, 244 }; 245 246 mipi_dsi_generic_write(ts->dsi, msg, sizeof(msg)); 247 248 return 0; 249 } 250 251 static int rpi_touchscreen_disable(struct drm_panel *panel) 252 { 253 struct rpi_touchscreen *ts = panel_to_ts(panel); 254 255 rpi_touchscreen_i2c_write(ts, REG_PWM, 0); 256 257 rpi_touchscreen_i2c_write(ts, REG_POWERON, 0); 258 udelay(1); 259 260 return 0; 261 } 262 263 static int rpi_touchscreen_noop(struct drm_panel *panel) 264 { 265 return 0; 266 } 267 268 static int rpi_touchscreen_prepare(struct drm_panel *panel) 269 { 270 struct rpi_touchscreen *ts = panel_to_ts(panel); 271 int i; 272 273 rpi_touchscreen_i2c_write(ts, REG_POWERON, 1); 274 /* Wait for nPWRDWN to go low to indicate poweron is done. */ 275 for (i = 0; i < 100; i++) { 276 if (rpi_touchscreen_i2c_read(ts, REG_PORTB) & 1) 277 break; 278 } 279 280 rpi_touchscreen_write(ts, DSI_LANEENABLE, 281 DSI_LANEENABLE_CLOCK | 282 DSI_LANEENABLE_D0); 283 rpi_touchscreen_write(ts, PPI_D0S_CLRSIPOCOUNT, 0x05); 284 rpi_touchscreen_write(ts, PPI_D1S_CLRSIPOCOUNT, 0x05); 285 rpi_touchscreen_write(ts, PPI_D0S_ATMR, 0x00); 286 rpi_touchscreen_write(ts, PPI_D1S_ATMR, 0x00); 287 rpi_touchscreen_write(ts, PPI_LPTXTIMECNT, 0x03); 288 289 rpi_touchscreen_write(ts, SPICMR, 0x00); 290 rpi_touchscreen_write(ts, LCDCTRL, 0x00100150); 291 rpi_touchscreen_write(ts, SYSCTRL, 0x040f); 292 msleep(100); 293 294 rpi_touchscreen_write(ts, PPI_STARTPPI, 0x01); 295 rpi_touchscreen_write(ts, DSI_STARTDSI, 0x01); 296 msleep(100); 297 298 return 0; 299 } 300 301 static int rpi_touchscreen_enable(struct drm_panel *panel) 302 { 303 struct rpi_touchscreen *ts = panel_to_ts(panel); 304 305 /* Turn on the backlight. */ 306 rpi_touchscreen_i2c_write(ts, REG_PWM, 255); 307 308 /* Default to the same orientation as the closed source 309 * firmware used for the panel. Runtime rotation 310 * configuration will be supported using VC4's plane 311 * orientation bits. 312 */ 313 rpi_touchscreen_i2c_write(ts, REG_PORTA, BIT(2)); 314 315 return 0; 316 } 317 318 static int rpi_touchscreen_get_modes(struct drm_panel *panel, 319 struct drm_connector *connector) 320 { 321 unsigned int i, num = 0; 322 static const u32 bus_format = MEDIA_BUS_FMT_RGB888_1X24; 323 324 for (i = 0; i < ARRAY_SIZE(rpi_touchscreen_modes); i++) { 325 const struct drm_display_mode *m = &rpi_touchscreen_modes[i]; 326 struct drm_display_mode *mode; 327 328 mode = drm_mode_duplicate(connector->dev, m); 329 if (!mode) { 330 dev_err(panel->dev, "failed to add mode %ux%u@%u\n", 331 m->hdisplay, m->vdisplay, 332 drm_mode_vrefresh(m)); 333 continue; 334 } 335 336 mode->type |= DRM_MODE_TYPE_DRIVER; 337 338 if (i == 0) 339 mode->type |= DRM_MODE_TYPE_PREFERRED; 340 341 drm_mode_set_name(mode); 342 343 drm_mode_probed_add(connector, mode); 344 num++; 345 } 346 347 connector->display_info.bpc = 8; 348 connector->display_info.width_mm = 154; 349 connector->display_info.height_mm = 86; 350 drm_display_info_set_bus_formats(&connector->display_info, 351 &bus_format, 1); 352 353 return num; 354 } 355 356 static const struct drm_panel_funcs rpi_touchscreen_funcs = { 357 .disable = rpi_touchscreen_disable, 358 .unprepare = rpi_touchscreen_noop, 359 .prepare = rpi_touchscreen_prepare, 360 .enable = rpi_touchscreen_enable, 361 .get_modes = rpi_touchscreen_get_modes, 362 }; 363 364 static int rpi_touchscreen_probe(struct i2c_client *i2c) 365 { 366 struct device *dev = &i2c->dev; 367 struct rpi_touchscreen *ts; 368 struct device_node *endpoint, *dsi_host_node; 369 struct mipi_dsi_host *host; 370 int ver; 371 struct mipi_dsi_device_info info = { 372 .type = RPI_DSI_DRIVER_NAME, 373 .channel = 0, 374 .node = NULL, 375 }; 376 377 ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL); 378 if (!ts) 379 return -ENOMEM; 380 381 i2c_set_clientdata(i2c, ts); 382 383 ts->i2c = i2c; 384 385 ver = rpi_touchscreen_i2c_read(ts, REG_ID); 386 if (ver < 0) { 387 dev_err(dev, "Atmel I2C read failed: %d\n", ver); 388 return -ENODEV; 389 } 390 391 switch (ver) { 392 case 0xde: /* ver 1 */ 393 case 0xc3: /* ver 2 */ 394 break; 395 default: 396 dev_err(dev, "Unknown Atmel firmware revision: 0x%02x\n", ver); 397 return -ENODEV; 398 } 399 400 /* Turn off at boot, so we can cleanly sequence powering on. */ 401 rpi_touchscreen_i2c_write(ts, REG_POWERON, 0); 402 403 /* Look up the DSI host. It needs to probe before we do. */ 404 endpoint = of_graph_get_next_endpoint(dev->of_node, NULL); 405 if (!endpoint) 406 return -ENODEV; 407 408 dsi_host_node = of_graph_get_remote_port_parent(endpoint); 409 if (!dsi_host_node) 410 goto error; 411 412 host = of_find_mipi_dsi_host_by_node(dsi_host_node); 413 of_node_put(dsi_host_node); 414 if (!host) { 415 of_node_put(endpoint); 416 return -EPROBE_DEFER; 417 } 418 419 info.node = of_graph_get_remote_port(endpoint); 420 if (!info.node) 421 goto error; 422 423 of_node_put(endpoint); 424 425 ts->dsi = mipi_dsi_device_register_full(host, &info); 426 if (IS_ERR(ts->dsi)) { 427 dev_err(dev, "DSI device registration failed: %ld\n", 428 PTR_ERR(ts->dsi)); 429 return PTR_ERR(ts->dsi); 430 } 431 432 drm_panel_init(&ts->base, dev, &rpi_touchscreen_funcs, 433 DRM_MODE_CONNECTOR_DSI); 434 435 /* This appears last, as it's what will unblock the DSI host 436 * driver's component bind function. 437 */ 438 drm_panel_add(&ts->base); 439 440 return 0; 441 442 error: 443 of_node_put(endpoint); 444 return -ENODEV; 445 } 446 447 static void rpi_touchscreen_remove(struct i2c_client *i2c) 448 { 449 struct rpi_touchscreen *ts = i2c_get_clientdata(i2c); 450 451 mipi_dsi_detach(ts->dsi); 452 453 drm_panel_remove(&ts->base); 454 455 mipi_dsi_device_unregister(ts->dsi); 456 } 457 458 static int rpi_touchscreen_dsi_probe(struct mipi_dsi_device *dsi) 459 { 460 int ret; 461 462 dsi->mode_flags = (MIPI_DSI_MODE_VIDEO | 463 MIPI_DSI_MODE_VIDEO_SYNC_PULSE | 464 MIPI_DSI_MODE_LPM); 465 dsi->format = MIPI_DSI_FMT_RGB888; 466 dsi->lanes = 1; 467 468 ret = mipi_dsi_attach(dsi); 469 470 if (ret) 471 dev_err(&dsi->dev, "failed to attach dsi to host: %d\n", ret); 472 473 return ret; 474 } 475 476 static struct mipi_dsi_driver rpi_touchscreen_dsi_driver = { 477 .driver.name = RPI_DSI_DRIVER_NAME, 478 .probe = rpi_touchscreen_dsi_probe, 479 }; 480 481 static const struct of_device_id rpi_touchscreen_of_ids[] = { 482 { .compatible = "raspberrypi,7inch-touchscreen-panel" }, 483 { } /* sentinel */ 484 }; 485 MODULE_DEVICE_TABLE(of, rpi_touchscreen_of_ids); 486 487 static struct i2c_driver rpi_touchscreen_driver = { 488 .driver = { 489 .name = "rpi_touchscreen", 490 .of_match_table = rpi_touchscreen_of_ids, 491 }, 492 .probe = rpi_touchscreen_probe, 493 .remove = rpi_touchscreen_remove, 494 }; 495 496 static int __init rpi_touchscreen_init(void) 497 { 498 mipi_dsi_driver_register(&rpi_touchscreen_dsi_driver); 499 return i2c_add_driver(&rpi_touchscreen_driver); 500 } 501 module_init(rpi_touchscreen_init); 502 503 static void __exit rpi_touchscreen_exit(void) 504 { 505 i2c_del_driver(&rpi_touchscreen_driver); 506 mipi_dsi_driver_unregister(&rpi_touchscreen_dsi_driver); 507 } 508 module_exit(rpi_touchscreen_exit); 509 510 MODULE_AUTHOR("Eric Anholt <eric@anholt.net>"); 511 MODULE_DESCRIPTION("Raspberry Pi 7-inch touchscreen driver"); 512 MODULE_LICENSE("GPL v2"); 513