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_graph.h> 51 #include <linux/pm.h> 52 53 #include <drm/drm_crtc.h> 54 #include <drm/drm_device.h> 55 #include <drm/drm_mipi_dsi.h> 56 #include <drm/drm_panel.h> 57 58 #define RPI_DSI_DRIVER_NAME "rpi-ts-dsi" 59 60 /* I2C registers of the Atmel microcontroller. */ 61 enum REG_ADDR { 62 REG_ID = 0x80, 63 REG_PORTA, /* BIT(2) for horizontal flip, BIT(3) for vertical flip */ 64 REG_PORTB, 65 REG_PORTC, 66 REG_PORTD, 67 REG_POWERON, 68 REG_PWM, 69 REG_DDRA, 70 REG_DDRB, 71 REG_DDRC, 72 REG_DDRD, 73 REG_TEST, 74 REG_WR_ADDRL, 75 REG_WR_ADDRH, 76 REG_READH, 77 REG_READL, 78 REG_WRITEH, 79 REG_WRITEL, 80 REG_ID2, 81 }; 82 83 /* DSI D-PHY Layer Registers */ 84 #define D0W_DPHYCONTTX 0x0004 85 #define CLW_DPHYCONTRX 0x0020 86 #define D0W_DPHYCONTRX 0x0024 87 #define D1W_DPHYCONTRX 0x0028 88 #define COM_DPHYCONTRX 0x0038 89 #define CLW_CNTRL 0x0040 90 #define D0W_CNTRL 0x0044 91 #define D1W_CNTRL 0x0048 92 #define DFTMODE_CNTRL 0x0054 93 94 /* DSI PPI Layer Registers */ 95 #define PPI_STARTPPI 0x0104 96 #define PPI_BUSYPPI 0x0108 97 #define PPI_LINEINITCNT 0x0110 98 #define PPI_LPTXTIMECNT 0x0114 99 #define PPI_CLS_ATMR 0x0140 100 #define PPI_D0S_ATMR 0x0144 101 #define PPI_D1S_ATMR 0x0148 102 #define PPI_D0S_CLRSIPOCOUNT 0x0164 103 #define PPI_D1S_CLRSIPOCOUNT 0x0168 104 #define CLS_PRE 0x0180 105 #define D0S_PRE 0x0184 106 #define D1S_PRE 0x0188 107 #define CLS_PREP 0x01A0 108 #define D0S_PREP 0x01A4 109 #define D1S_PREP 0x01A8 110 #define CLS_ZERO 0x01C0 111 #define D0S_ZERO 0x01C4 112 #define D1S_ZERO 0x01C8 113 #define PPI_CLRFLG 0x01E0 114 #define PPI_CLRSIPO 0x01E4 115 #define HSTIMEOUT 0x01F0 116 #define HSTIMEOUTENABLE 0x01F4 117 118 /* DSI Protocol Layer Registers */ 119 #define DSI_STARTDSI 0x0204 120 #define DSI_BUSYDSI 0x0208 121 #define DSI_LANEENABLE 0x0210 122 # define DSI_LANEENABLE_CLOCK BIT(0) 123 # define DSI_LANEENABLE_D0 BIT(1) 124 # define DSI_LANEENABLE_D1 BIT(2) 125 126 #define DSI_LANESTATUS0 0x0214 127 #define DSI_LANESTATUS1 0x0218 128 #define DSI_INTSTATUS 0x0220 129 #define DSI_INTMASK 0x0224 130 #define DSI_INTCLR 0x0228 131 #define DSI_LPTXTO 0x0230 132 #define DSI_MODE 0x0260 133 #define DSI_PAYLOAD0 0x0268 134 #define DSI_PAYLOAD1 0x026C 135 #define DSI_SHORTPKTDAT 0x0270 136 #define DSI_SHORTPKTREQ 0x0274 137 #define DSI_BTASTA 0x0278 138 #define DSI_BTACLR 0x027C 139 140 /* DSI General Registers */ 141 #define DSIERRCNT 0x0300 142 #define DSISIGMOD 0x0304 143 144 /* DSI Application Layer Registers */ 145 #define APLCTRL 0x0400 146 #define APLSTAT 0x0404 147 #define APLERR 0x0408 148 #define PWRMOD 0x040C 149 #define RDPKTLN 0x0410 150 #define PXLFMT 0x0414 151 #define MEMWRCMD 0x0418 152 153 /* LCDC/DPI Host Registers */ 154 #define LCDCTRL 0x0420 155 #define HSR 0x0424 156 #define HDISPR 0x0428 157 #define VSR 0x042C 158 #define VDISPR 0x0430 159 #define VFUEN 0x0434 160 161 /* DBI-B Host Registers */ 162 #define DBIBCTRL 0x0440 163 164 /* SPI Master Registers */ 165 #define SPICMR 0x0450 166 #define SPITCR 0x0454 167 168 /* System Controller Registers */ 169 #define SYSSTAT 0x0460 170 #define SYSCTRL 0x0464 171 #define SYSPLL1 0x0468 172 #define SYSPLL2 0x046C 173 #define SYSPLL3 0x0470 174 #define SYSPMCTRL 0x047C 175 176 /* GPIO Registers */ 177 #define GPIOC 0x0480 178 #define GPIOO 0x0484 179 #define GPIOI 0x0488 180 181 /* I2C Registers */ 182 #define I2CCLKCTRL 0x0490 183 184 /* Chip/Rev Registers */ 185 #define IDREG 0x04A0 186 187 /* Debug Registers */ 188 #define WCMDQUEUE 0x0500 189 #define RCMDQUEUE 0x0504 190 191 struct rpi_touchscreen { 192 struct drm_panel base; 193 struct mipi_dsi_device *dsi; 194 struct i2c_client *i2c; 195 }; 196 197 static const struct drm_display_mode rpi_touchscreen_modes[] = { 198 { 199 /* Modeline comes from the Raspberry Pi firmware, with HFP=1 200 * plugged in and clock re-computed from that. 201 */ 202 .clock = 25979400 / 1000, 203 .hdisplay = 800, 204 .hsync_start = 800 + 1, 205 .hsync_end = 800 + 1 + 2, 206 .htotal = 800 + 1 + 2 + 46, 207 .vdisplay = 480, 208 .vsync_start = 480 + 7, 209 .vsync_end = 480 + 7 + 2, 210 .vtotal = 480 + 7 + 2 + 21, 211 }, 212 }; 213 214 static struct rpi_touchscreen *panel_to_ts(struct drm_panel *panel) 215 { 216 return container_of(panel, struct rpi_touchscreen, base); 217 } 218 219 static int rpi_touchscreen_i2c_read(struct rpi_touchscreen *ts, u8 reg) 220 { 221 return i2c_smbus_read_byte_data(ts->i2c, reg); 222 } 223 224 static void rpi_touchscreen_i2c_write(struct rpi_touchscreen *ts, 225 u8 reg, u8 val) 226 { 227 int ret; 228 229 ret = i2c_smbus_write_byte_data(ts->i2c, reg, val); 230 if (ret) 231 dev_err(&ts->i2c->dev, "I2C write failed: %d\n", ret); 232 } 233 234 static int rpi_touchscreen_write(struct rpi_touchscreen *ts, u16 reg, u32 val) 235 { 236 u8 msg[] = { 237 reg, 238 reg >> 8, 239 val, 240 val >> 8, 241 val >> 16, 242 val >> 24, 243 }; 244 245 mipi_dsi_generic_write(ts->dsi, msg, sizeof(msg)); 246 247 return 0; 248 } 249 250 static int rpi_touchscreen_disable(struct drm_panel *panel) 251 { 252 struct rpi_touchscreen *ts = panel_to_ts(panel); 253 254 rpi_touchscreen_i2c_write(ts, REG_PWM, 0); 255 256 rpi_touchscreen_i2c_write(ts, REG_POWERON, 0); 257 udelay(1); 258 259 return 0; 260 } 261 262 static int rpi_touchscreen_noop(struct drm_panel *panel) 263 { 264 return 0; 265 } 266 267 static int rpi_touchscreen_prepare(struct drm_panel *panel) 268 { 269 struct rpi_touchscreen *ts = panel_to_ts(panel); 270 int i; 271 272 rpi_touchscreen_i2c_write(ts, REG_POWERON, 1); 273 /* Wait for nPWRDWN to go low to indicate poweron is done. */ 274 for (i = 0; i < 100; i++) { 275 if (rpi_touchscreen_i2c_read(ts, REG_PORTB) & 1) 276 break; 277 } 278 279 rpi_touchscreen_write(ts, DSI_LANEENABLE, 280 DSI_LANEENABLE_CLOCK | 281 DSI_LANEENABLE_D0); 282 rpi_touchscreen_write(ts, PPI_D0S_CLRSIPOCOUNT, 0x05); 283 rpi_touchscreen_write(ts, PPI_D1S_CLRSIPOCOUNT, 0x05); 284 rpi_touchscreen_write(ts, PPI_D0S_ATMR, 0x00); 285 rpi_touchscreen_write(ts, PPI_D1S_ATMR, 0x00); 286 rpi_touchscreen_write(ts, PPI_LPTXTIMECNT, 0x03); 287 288 rpi_touchscreen_write(ts, SPICMR, 0x00); 289 rpi_touchscreen_write(ts, LCDCTRL, 0x00100150); 290 rpi_touchscreen_write(ts, SYSCTRL, 0x040f); 291 msleep(100); 292 293 rpi_touchscreen_write(ts, PPI_STARTPPI, 0x01); 294 rpi_touchscreen_write(ts, DSI_STARTDSI, 0x01); 295 msleep(100); 296 297 return 0; 298 } 299 300 static int rpi_touchscreen_enable(struct drm_panel *panel) 301 { 302 struct rpi_touchscreen *ts = panel_to_ts(panel); 303 304 /* Turn on the backlight. */ 305 rpi_touchscreen_i2c_write(ts, REG_PWM, 255); 306 307 /* Default to the same orientation as the closed source 308 * firmware used for the panel. Runtime rotation 309 * configuration will be supported using VC4's plane 310 * orientation bits. 311 */ 312 rpi_touchscreen_i2c_write(ts, REG_PORTA, BIT(2)); 313 314 return 0; 315 } 316 317 static int rpi_touchscreen_get_modes(struct drm_panel *panel, 318 struct drm_connector *connector) 319 { 320 unsigned int i, num = 0; 321 static const u32 bus_format = MEDIA_BUS_FMT_RGB888_1X24; 322 323 for (i = 0; i < ARRAY_SIZE(rpi_touchscreen_modes); i++) { 324 const struct drm_display_mode *m = &rpi_touchscreen_modes[i]; 325 struct drm_display_mode *mode; 326 327 mode = drm_mode_duplicate(connector->dev, m); 328 if (!mode) { 329 dev_err(panel->dev, "failed to add mode %ux%u@%u\n", 330 m->hdisplay, m->vdisplay, 331 drm_mode_vrefresh(m)); 332 continue; 333 } 334 335 mode->type |= DRM_MODE_TYPE_DRIVER; 336 337 if (i == 0) 338 mode->type |= DRM_MODE_TYPE_PREFERRED; 339 340 drm_mode_set_name(mode); 341 342 drm_mode_probed_add(connector, mode); 343 num++; 344 } 345 346 connector->display_info.bpc = 8; 347 connector->display_info.width_mm = 154; 348 connector->display_info.height_mm = 86; 349 drm_display_info_set_bus_formats(&connector->display_info, 350 &bus_format, 1); 351 352 return num; 353 } 354 355 static const struct drm_panel_funcs rpi_touchscreen_funcs = { 356 .disable = rpi_touchscreen_disable, 357 .unprepare = rpi_touchscreen_noop, 358 .prepare = rpi_touchscreen_prepare, 359 .enable = rpi_touchscreen_enable, 360 .get_modes = rpi_touchscreen_get_modes, 361 }; 362 363 static int rpi_touchscreen_probe(struct i2c_client *i2c) 364 { 365 struct device *dev = &i2c->dev; 366 struct rpi_touchscreen *ts; 367 struct device_node *endpoint, *dsi_host_node; 368 struct mipi_dsi_host *host; 369 int ver; 370 struct mipi_dsi_device_info info = { 371 .type = RPI_DSI_DRIVER_NAME, 372 .channel = 0, 373 .node = NULL, 374 }; 375 376 ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL); 377 if (!ts) 378 return -ENOMEM; 379 380 i2c_set_clientdata(i2c, ts); 381 382 ts->i2c = i2c; 383 384 ver = rpi_touchscreen_i2c_read(ts, REG_ID); 385 if (ver < 0) { 386 dev_err(dev, "Atmel I2C read failed: %d\n", ver); 387 return -ENODEV; 388 } 389 390 switch (ver) { 391 case 0xde: /* ver 1 */ 392 case 0xc3: /* ver 2 */ 393 break; 394 default: 395 dev_err(dev, "Unknown Atmel firmware revision: 0x%02x\n", ver); 396 return -ENODEV; 397 } 398 399 /* Turn off at boot, so we can cleanly sequence powering on. */ 400 rpi_touchscreen_i2c_write(ts, REG_POWERON, 0); 401 402 /* Look up the DSI host. It needs to probe before we do. */ 403 endpoint = of_graph_get_next_endpoint(dev->of_node, NULL); 404 if (!endpoint) 405 return -ENODEV; 406 407 dsi_host_node = of_graph_get_remote_port_parent(endpoint); 408 if (!dsi_host_node) 409 goto error; 410 411 host = of_find_mipi_dsi_host_by_node(dsi_host_node); 412 of_node_put(dsi_host_node); 413 if (!host) { 414 of_node_put(endpoint); 415 return -EPROBE_DEFER; 416 } 417 418 info.node = of_graph_get_remote_port(endpoint); 419 if (!info.node) 420 goto error; 421 422 of_node_put(endpoint); 423 424 ts->dsi = mipi_dsi_device_register_full(host, &info); 425 if (IS_ERR(ts->dsi)) { 426 dev_err(dev, "DSI device registration failed: %ld\n", 427 PTR_ERR(ts->dsi)); 428 return PTR_ERR(ts->dsi); 429 } 430 431 drm_panel_init(&ts->base, dev, &rpi_touchscreen_funcs, 432 DRM_MODE_CONNECTOR_DSI); 433 434 /* This appears last, as it's what will unblock the DSI host 435 * driver's component bind function. 436 */ 437 drm_panel_add(&ts->base); 438 439 return 0; 440 441 error: 442 of_node_put(endpoint); 443 return -ENODEV; 444 } 445 446 static void rpi_touchscreen_remove(struct i2c_client *i2c) 447 { 448 struct rpi_touchscreen *ts = i2c_get_clientdata(i2c); 449 450 mipi_dsi_detach(ts->dsi); 451 452 drm_panel_remove(&ts->base); 453 454 mipi_dsi_device_unregister(ts->dsi); 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