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/fb.h> 47 #include <linux/i2c.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 .vrefresh = 60, 213 }, 214 }; 215 216 static struct rpi_touchscreen *panel_to_ts(struct drm_panel *panel) 217 { 218 return container_of(panel, struct rpi_touchscreen, base); 219 } 220 221 static int rpi_touchscreen_i2c_read(struct rpi_touchscreen *ts, u8 reg) 222 { 223 return i2c_smbus_read_byte_data(ts->i2c, reg); 224 } 225 226 static void rpi_touchscreen_i2c_write(struct rpi_touchscreen *ts, 227 u8 reg, u8 val) 228 { 229 int ret; 230 231 ret = i2c_smbus_write_byte_data(ts->i2c, reg, val); 232 if (ret) 233 dev_err(&ts->dsi->dev, "I2C write failed: %d\n", ret); 234 } 235 236 static int rpi_touchscreen_write(struct rpi_touchscreen *ts, u16 reg, u32 val) 237 { 238 u8 msg[] = { 239 reg, 240 reg >> 8, 241 val, 242 val >> 8, 243 val >> 16, 244 val >> 24, 245 }; 246 247 mipi_dsi_generic_write(ts->dsi, msg, sizeof(msg)); 248 249 return 0; 250 } 251 252 static int rpi_touchscreen_disable(struct drm_panel *panel) 253 { 254 struct rpi_touchscreen *ts = panel_to_ts(panel); 255 256 rpi_touchscreen_i2c_write(ts, REG_PWM, 0); 257 258 rpi_touchscreen_i2c_write(ts, REG_POWERON, 0); 259 udelay(1); 260 261 return 0; 262 } 263 264 static int rpi_touchscreen_noop(struct drm_panel *panel) 265 { 266 return 0; 267 } 268 269 static int rpi_touchscreen_enable(struct drm_panel *panel) 270 { 271 struct rpi_touchscreen *ts = panel_to_ts(panel); 272 int i; 273 274 rpi_touchscreen_i2c_write(ts, REG_POWERON, 1); 275 /* Wait for nPWRDWN to go low to indicate poweron is done. */ 276 for (i = 0; i < 100; i++) { 277 if (rpi_touchscreen_i2c_read(ts, REG_PORTB) & 1) 278 break; 279 } 280 281 rpi_touchscreen_write(ts, DSI_LANEENABLE, 282 DSI_LANEENABLE_CLOCK | 283 DSI_LANEENABLE_D0); 284 rpi_touchscreen_write(ts, PPI_D0S_CLRSIPOCOUNT, 0x05); 285 rpi_touchscreen_write(ts, PPI_D1S_CLRSIPOCOUNT, 0x05); 286 rpi_touchscreen_write(ts, PPI_D0S_ATMR, 0x00); 287 rpi_touchscreen_write(ts, PPI_D1S_ATMR, 0x00); 288 rpi_touchscreen_write(ts, PPI_LPTXTIMECNT, 0x03); 289 290 rpi_touchscreen_write(ts, SPICMR, 0x00); 291 rpi_touchscreen_write(ts, LCDCTRL, 0x00100150); 292 rpi_touchscreen_write(ts, SYSCTRL, 0x040f); 293 msleep(100); 294 295 rpi_touchscreen_write(ts, PPI_STARTPPI, 0x01); 296 rpi_touchscreen_write(ts, DSI_STARTDSI, 0x01); 297 msleep(100); 298 299 /* Turn on the backlight. */ 300 rpi_touchscreen_i2c_write(ts, REG_PWM, 255); 301 302 /* Default to the same orientation as the closed source 303 * firmware used for the panel. Runtime rotation 304 * configuration will be supported using VC4's plane 305 * orientation bits. 306 */ 307 rpi_touchscreen_i2c_write(ts, REG_PORTA, BIT(2)); 308 309 return 0; 310 } 311 312 static int rpi_touchscreen_get_modes(struct drm_panel *panel, 313 struct drm_connector *connector) 314 { 315 unsigned int i, num = 0; 316 static const u32 bus_format = MEDIA_BUS_FMT_RGB888_1X24; 317 318 for (i = 0; i < ARRAY_SIZE(rpi_touchscreen_modes); i++) { 319 const struct drm_display_mode *m = &rpi_touchscreen_modes[i]; 320 struct drm_display_mode *mode; 321 322 mode = drm_mode_duplicate(connector->dev, m); 323 if (!mode) { 324 dev_err(panel->dev, "failed to add mode %ux%u@%u\n", 325 m->hdisplay, m->vdisplay, m->vrefresh); 326 continue; 327 } 328 329 mode->type |= DRM_MODE_TYPE_DRIVER; 330 331 if (i == 0) 332 mode->type |= DRM_MODE_TYPE_PREFERRED; 333 334 drm_mode_set_name(mode); 335 336 drm_mode_probed_add(connector, mode); 337 num++; 338 } 339 340 connector->display_info.bpc = 8; 341 connector->display_info.width_mm = 154; 342 connector->display_info.height_mm = 86; 343 drm_display_info_set_bus_formats(&connector->display_info, 344 &bus_format, 1); 345 346 return num; 347 } 348 349 static const struct drm_panel_funcs rpi_touchscreen_funcs = { 350 .disable = rpi_touchscreen_disable, 351 .unprepare = rpi_touchscreen_noop, 352 .prepare = rpi_touchscreen_noop, 353 .enable = rpi_touchscreen_enable, 354 .get_modes = rpi_touchscreen_get_modes, 355 }; 356 357 static int rpi_touchscreen_probe(struct i2c_client *i2c, 358 const struct i2c_device_id *id) 359 { 360 struct device *dev = &i2c->dev; 361 struct rpi_touchscreen *ts; 362 struct device_node *endpoint, *dsi_host_node; 363 struct mipi_dsi_host *host; 364 int ret, ver; 365 struct mipi_dsi_device_info info = { 366 .type = RPI_DSI_DRIVER_NAME, 367 .channel = 0, 368 .node = NULL, 369 }; 370 371 ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL); 372 if (!ts) 373 return -ENOMEM; 374 375 i2c_set_clientdata(i2c, ts); 376 377 ts->i2c = i2c; 378 379 ver = rpi_touchscreen_i2c_read(ts, REG_ID); 380 if (ver < 0) { 381 dev_err(dev, "Atmel I2C read failed: %d\n", ver); 382 return -ENODEV; 383 } 384 385 switch (ver) { 386 case 0xde: /* ver 1 */ 387 case 0xc3: /* ver 2 */ 388 break; 389 default: 390 dev_err(dev, "Unknown Atmel firmware revision: 0x%02x\n", ver); 391 return -ENODEV; 392 } 393 394 /* Turn off at boot, so we can cleanly sequence powering on. */ 395 rpi_touchscreen_i2c_write(ts, REG_POWERON, 0); 396 397 /* Look up the DSI host. It needs to probe before we do. */ 398 endpoint = of_graph_get_next_endpoint(dev->of_node, NULL); 399 if (!endpoint) 400 return -ENODEV; 401 402 dsi_host_node = of_graph_get_remote_port_parent(endpoint); 403 if (!dsi_host_node) 404 goto error; 405 406 host = of_find_mipi_dsi_host_by_node(dsi_host_node); 407 of_node_put(dsi_host_node); 408 if (!host) { 409 of_node_put(endpoint); 410 return -EPROBE_DEFER; 411 } 412 413 info.node = of_graph_get_remote_port(endpoint); 414 if (!info.node) 415 goto error; 416 417 of_node_put(endpoint); 418 419 ts->dsi = mipi_dsi_device_register_full(host, &info); 420 if (IS_ERR(ts->dsi)) { 421 dev_err(dev, "DSI device registration failed: %ld\n", 422 PTR_ERR(ts->dsi)); 423 return PTR_ERR(ts->dsi); 424 } 425 426 drm_panel_init(&ts->base, dev, &rpi_touchscreen_funcs, 427 DRM_MODE_CONNECTOR_DSI); 428 429 /* This appears last, as it's what will unblock the DSI host 430 * driver's component bind function. 431 */ 432 ret = drm_panel_add(&ts->base); 433 if (ret) 434 return ret; 435 436 return 0; 437 438 error: 439 of_node_put(endpoint); 440 return -ENODEV; 441 } 442 443 static int rpi_touchscreen_remove(struct i2c_client *i2c) 444 { 445 struct rpi_touchscreen *ts = i2c_get_clientdata(i2c); 446 447 mipi_dsi_detach(ts->dsi); 448 449 drm_panel_remove(&ts->base); 450 451 mipi_dsi_device_unregister(ts->dsi); 452 kfree(ts->dsi); 453 454 return 0; 455 } 456 457 static int rpi_touchscreen_dsi_probe(struct mipi_dsi_device *dsi) 458 { 459 int ret; 460 461 dsi->mode_flags = (MIPI_DSI_MODE_VIDEO | 462 MIPI_DSI_MODE_VIDEO_SYNC_PULSE | 463 MIPI_DSI_MODE_LPM); 464 dsi->format = MIPI_DSI_FMT_RGB888; 465 dsi->lanes = 1; 466 467 ret = mipi_dsi_attach(dsi); 468 469 if (ret) 470 dev_err(&dsi->dev, "failed to attach dsi to host: %d\n", ret); 471 472 return ret; 473 } 474 475 static struct mipi_dsi_driver rpi_touchscreen_dsi_driver = { 476 .driver.name = RPI_DSI_DRIVER_NAME, 477 .probe = rpi_touchscreen_dsi_probe, 478 }; 479 480 static const struct of_device_id rpi_touchscreen_of_ids[] = { 481 { .compatible = "raspberrypi,7inch-touchscreen-panel" }, 482 { } /* sentinel */ 483 }; 484 MODULE_DEVICE_TABLE(of, rpi_touchscreen_of_ids); 485 486 static struct i2c_driver rpi_touchscreen_driver = { 487 .driver = { 488 .name = "rpi_touchscreen", 489 .of_match_table = rpi_touchscreen_of_ids, 490 }, 491 .probe = rpi_touchscreen_probe, 492 .remove = rpi_touchscreen_remove, 493 }; 494 495 static int __init rpi_touchscreen_init(void) 496 { 497 mipi_dsi_driver_register(&rpi_touchscreen_dsi_driver); 498 return i2c_add_driver(&rpi_touchscreen_driver); 499 } 500 module_init(rpi_touchscreen_init); 501 502 static void __exit rpi_touchscreen_exit(void) 503 { 504 i2c_del_driver(&rpi_touchscreen_driver); 505 mipi_dsi_driver_unregister(&rpi_touchscreen_dsi_driver); 506 } 507 module_exit(rpi_touchscreen_exit); 508 509 MODULE_AUTHOR("Eric Anholt <eric@anholt.net>"); 510 MODULE_DESCRIPTION("Raspberry Pi 7-inch touchscreen driver"); 511 MODULE_LICENSE("GPL v2"); 512