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/gpio.h> 48 #include <linux/gpio/consumer.h> 49 #include <linux/i2c.h> 50 #include <linux/module.h> 51 #include <linux/of.h> 52 #include <linux/of_device.h> 53 #include <linux/of_graph.h> 54 #include <linux/pm.h> 55 56 #include <drm/drm_crtc.h> 57 #include <drm/drm_device.h> 58 #include <drm/drm_mipi_dsi.h> 59 #include <drm/drm_panel.h> 60 61 #define RPI_DSI_DRIVER_NAME "rpi-ts-dsi" 62 63 /* I2C registers of the Atmel microcontroller. */ 64 enum REG_ADDR { 65 REG_ID = 0x80, 66 REG_PORTA, /* BIT(2) for horizontal flip, BIT(3) for vertical flip */ 67 REG_PORTB, 68 REG_PORTC, 69 REG_PORTD, 70 REG_POWERON, 71 REG_PWM, 72 REG_DDRA, 73 REG_DDRB, 74 REG_DDRC, 75 REG_DDRD, 76 REG_TEST, 77 REG_WR_ADDRL, 78 REG_WR_ADDRH, 79 REG_READH, 80 REG_READL, 81 REG_WRITEH, 82 REG_WRITEL, 83 REG_ID2, 84 }; 85 86 /* DSI D-PHY Layer Registers */ 87 #define D0W_DPHYCONTTX 0x0004 88 #define CLW_DPHYCONTRX 0x0020 89 #define D0W_DPHYCONTRX 0x0024 90 #define D1W_DPHYCONTRX 0x0028 91 #define COM_DPHYCONTRX 0x0038 92 #define CLW_CNTRL 0x0040 93 #define D0W_CNTRL 0x0044 94 #define D1W_CNTRL 0x0048 95 #define DFTMODE_CNTRL 0x0054 96 97 /* DSI PPI Layer Registers */ 98 #define PPI_STARTPPI 0x0104 99 #define PPI_BUSYPPI 0x0108 100 #define PPI_LINEINITCNT 0x0110 101 #define PPI_LPTXTIMECNT 0x0114 102 #define PPI_CLS_ATMR 0x0140 103 #define PPI_D0S_ATMR 0x0144 104 #define PPI_D1S_ATMR 0x0148 105 #define PPI_D0S_CLRSIPOCOUNT 0x0164 106 #define PPI_D1S_CLRSIPOCOUNT 0x0168 107 #define CLS_PRE 0x0180 108 #define D0S_PRE 0x0184 109 #define D1S_PRE 0x0188 110 #define CLS_PREP 0x01A0 111 #define D0S_PREP 0x01A4 112 #define D1S_PREP 0x01A8 113 #define CLS_ZERO 0x01C0 114 #define D0S_ZERO 0x01C4 115 #define D1S_ZERO 0x01C8 116 #define PPI_CLRFLG 0x01E0 117 #define PPI_CLRSIPO 0x01E4 118 #define HSTIMEOUT 0x01F0 119 #define HSTIMEOUTENABLE 0x01F4 120 121 /* DSI Protocol Layer Registers */ 122 #define DSI_STARTDSI 0x0204 123 #define DSI_BUSYDSI 0x0208 124 #define DSI_LANEENABLE 0x0210 125 # define DSI_LANEENABLE_CLOCK BIT(0) 126 # define DSI_LANEENABLE_D0 BIT(1) 127 # define DSI_LANEENABLE_D1 BIT(2) 128 129 #define DSI_LANESTATUS0 0x0214 130 #define DSI_LANESTATUS1 0x0218 131 #define DSI_INTSTATUS 0x0220 132 #define DSI_INTMASK 0x0224 133 #define DSI_INTCLR 0x0228 134 #define DSI_LPTXTO 0x0230 135 #define DSI_MODE 0x0260 136 #define DSI_PAYLOAD0 0x0268 137 #define DSI_PAYLOAD1 0x026C 138 #define DSI_SHORTPKTDAT 0x0270 139 #define DSI_SHORTPKTREQ 0x0274 140 #define DSI_BTASTA 0x0278 141 #define DSI_BTACLR 0x027C 142 143 /* DSI General Registers */ 144 #define DSIERRCNT 0x0300 145 #define DSISIGMOD 0x0304 146 147 /* DSI Application Layer Registers */ 148 #define APLCTRL 0x0400 149 #define APLSTAT 0x0404 150 #define APLERR 0x0408 151 #define PWRMOD 0x040C 152 #define RDPKTLN 0x0410 153 #define PXLFMT 0x0414 154 #define MEMWRCMD 0x0418 155 156 /* LCDC/DPI Host Registers */ 157 #define LCDCTRL 0x0420 158 #define HSR 0x0424 159 #define HDISPR 0x0428 160 #define VSR 0x042C 161 #define VDISPR 0x0430 162 #define VFUEN 0x0434 163 164 /* DBI-B Host Registers */ 165 #define DBIBCTRL 0x0440 166 167 /* SPI Master Registers */ 168 #define SPICMR 0x0450 169 #define SPITCR 0x0454 170 171 /* System Controller Registers */ 172 #define SYSSTAT 0x0460 173 #define SYSCTRL 0x0464 174 #define SYSPLL1 0x0468 175 #define SYSPLL2 0x046C 176 #define SYSPLL3 0x0470 177 #define SYSPMCTRL 0x047C 178 179 /* GPIO Registers */ 180 #define GPIOC 0x0480 181 #define GPIOO 0x0484 182 #define GPIOI 0x0488 183 184 /* I2C Registers */ 185 #define I2CCLKCTRL 0x0490 186 187 /* Chip/Rev Registers */ 188 #define IDREG 0x04A0 189 190 /* Debug Registers */ 191 #define WCMDQUEUE 0x0500 192 #define RCMDQUEUE 0x0504 193 194 struct rpi_touchscreen { 195 struct drm_panel base; 196 struct mipi_dsi_device *dsi; 197 struct i2c_client *i2c; 198 }; 199 200 static const struct drm_display_mode rpi_touchscreen_modes[] = { 201 { 202 /* Modeline comes from the Raspberry Pi firmware, with HFP=1 203 * plugged in and clock re-computed from that. 204 */ 205 .clock = 25979400 / 1000, 206 .hdisplay = 800, 207 .hsync_start = 800 + 1, 208 .hsync_end = 800 + 1 + 2, 209 .htotal = 800 + 1 + 2 + 46, 210 .vdisplay = 480, 211 .vsync_start = 480 + 7, 212 .vsync_end = 480 + 7 + 2, 213 .vtotal = 480 + 7 + 2 + 21, 214 .vrefresh = 60, 215 }, 216 }; 217 218 static struct rpi_touchscreen *panel_to_ts(struct drm_panel *panel) 219 { 220 return container_of(panel, struct rpi_touchscreen, base); 221 } 222 223 static int rpi_touchscreen_i2c_read(struct rpi_touchscreen *ts, u8 reg) 224 { 225 return i2c_smbus_read_byte_data(ts->i2c, reg); 226 } 227 228 static void rpi_touchscreen_i2c_write(struct rpi_touchscreen *ts, 229 u8 reg, u8 val) 230 { 231 int ret; 232 233 ret = i2c_smbus_write_byte_data(ts->i2c, reg, val); 234 if (ret) 235 dev_err(&ts->dsi->dev, "I2C write failed: %d\n", ret); 236 } 237 238 static int rpi_touchscreen_write(struct rpi_touchscreen *ts, u16 reg, u32 val) 239 { 240 u8 msg[] = { 241 reg, 242 reg >> 8, 243 val, 244 val >> 8, 245 val >> 16, 246 val >> 24, 247 }; 248 249 mipi_dsi_generic_write(ts->dsi, msg, sizeof(msg)); 250 251 return 0; 252 } 253 254 static int rpi_touchscreen_disable(struct drm_panel *panel) 255 { 256 struct rpi_touchscreen *ts = panel_to_ts(panel); 257 258 rpi_touchscreen_i2c_write(ts, REG_PWM, 0); 259 260 rpi_touchscreen_i2c_write(ts, REG_POWERON, 0); 261 udelay(1); 262 263 return 0; 264 } 265 266 static int rpi_touchscreen_noop(struct drm_panel *panel) 267 { 268 return 0; 269 } 270 271 static int rpi_touchscreen_enable(struct drm_panel *panel) 272 { 273 struct rpi_touchscreen *ts = panel_to_ts(panel); 274 int i; 275 276 rpi_touchscreen_i2c_write(ts, REG_POWERON, 1); 277 /* Wait for nPWRDWN to go low to indicate poweron is done. */ 278 for (i = 0; i < 100; i++) { 279 if (rpi_touchscreen_i2c_read(ts, REG_PORTB) & 1) 280 break; 281 } 282 283 rpi_touchscreen_write(ts, DSI_LANEENABLE, 284 DSI_LANEENABLE_CLOCK | 285 DSI_LANEENABLE_D0); 286 rpi_touchscreen_write(ts, PPI_D0S_CLRSIPOCOUNT, 0x05); 287 rpi_touchscreen_write(ts, PPI_D1S_CLRSIPOCOUNT, 0x05); 288 rpi_touchscreen_write(ts, PPI_D0S_ATMR, 0x00); 289 rpi_touchscreen_write(ts, PPI_D1S_ATMR, 0x00); 290 rpi_touchscreen_write(ts, PPI_LPTXTIMECNT, 0x03); 291 292 rpi_touchscreen_write(ts, SPICMR, 0x00); 293 rpi_touchscreen_write(ts, LCDCTRL, 0x00100150); 294 rpi_touchscreen_write(ts, SYSCTRL, 0x040f); 295 msleep(100); 296 297 rpi_touchscreen_write(ts, PPI_STARTPPI, 0x01); 298 rpi_touchscreen_write(ts, DSI_STARTDSI, 0x01); 299 msleep(100); 300 301 /* Turn on the backlight. */ 302 rpi_touchscreen_i2c_write(ts, REG_PWM, 255); 303 304 /* Default to the same orientation as the closed source 305 * firmware used for the panel. Runtime rotation 306 * configuration will be supported using VC4's plane 307 * orientation bits. 308 */ 309 rpi_touchscreen_i2c_write(ts, REG_PORTA, BIT(2)); 310 311 return 0; 312 } 313 314 static int rpi_touchscreen_get_modes(struct drm_panel *panel) 315 { 316 struct drm_connector *connector = panel->connector; 317 struct drm_device *drm = panel->drm; 318 unsigned int i, num = 0; 319 static const u32 bus_format = MEDIA_BUS_FMT_RGB888_1X24; 320 321 for (i = 0; i < ARRAY_SIZE(rpi_touchscreen_modes); i++) { 322 const struct drm_display_mode *m = &rpi_touchscreen_modes[i]; 323 struct drm_display_mode *mode; 324 325 mode = drm_mode_duplicate(drm, m); 326 if (!mode) { 327 dev_err(drm->dev, "failed to add mode %ux%u@%u\n", 328 m->hdisplay, m->vdisplay, m->vrefresh); 329 continue; 330 } 331 332 mode->type |= DRM_MODE_TYPE_DRIVER; 333 334 if (i == 0) 335 mode->type |= DRM_MODE_TYPE_PREFERRED; 336 337 drm_mode_set_name(mode); 338 339 drm_mode_probed_add(connector, mode); 340 num++; 341 } 342 343 connector->display_info.bpc = 8; 344 connector->display_info.width_mm = 154; 345 connector->display_info.height_mm = 86; 346 drm_display_info_set_bus_formats(&connector->display_info, 347 &bus_format, 1); 348 349 return num; 350 } 351 352 static const struct drm_panel_funcs rpi_touchscreen_funcs = { 353 .disable = rpi_touchscreen_disable, 354 .unprepare = rpi_touchscreen_noop, 355 .prepare = rpi_touchscreen_noop, 356 .enable = rpi_touchscreen_enable, 357 .get_modes = rpi_touchscreen_get_modes, 358 }; 359 360 static int rpi_touchscreen_probe(struct i2c_client *i2c, 361 const struct i2c_device_id *id) 362 { 363 struct device *dev = &i2c->dev; 364 struct rpi_touchscreen *ts; 365 struct device_node *endpoint, *dsi_host_node; 366 struct mipi_dsi_host *host; 367 int ret, ver; 368 struct mipi_dsi_device_info info = { 369 .type = RPI_DSI_DRIVER_NAME, 370 .channel = 0, 371 .node = NULL, 372 }; 373 374 ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL); 375 if (!ts) 376 return -ENOMEM; 377 378 i2c_set_clientdata(i2c, ts); 379 380 ts->i2c = i2c; 381 382 ver = rpi_touchscreen_i2c_read(ts, REG_ID); 383 if (ver < 0) { 384 dev_err(dev, "Atmel I2C read failed: %d\n", ver); 385 return -ENODEV; 386 } 387 388 switch (ver) { 389 case 0xde: /* ver 1 */ 390 case 0xc3: /* ver 2 */ 391 break; 392 default: 393 dev_err(dev, "Unknown Atmel firmware revision: 0x%02x\n", ver); 394 return -ENODEV; 395 } 396 397 /* Turn off at boot, so we can cleanly sequence powering on. */ 398 rpi_touchscreen_i2c_write(ts, REG_POWERON, 0); 399 400 /* Look up the DSI host. It needs to probe before we do. */ 401 endpoint = of_graph_get_next_endpoint(dev->of_node, NULL); 402 if (!endpoint) 403 return -ENODEV; 404 405 dsi_host_node = of_graph_get_remote_port_parent(endpoint); 406 if (!dsi_host_node) 407 goto error; 408 409 host = of_find_mipi_dsi_host_by_node(dsi_host_node); 410 of_node_put(dsi_host_node); 411 if (!host) { 412 of_node_put(endpoint); 413 return -EPROBE_DEFER; 414 } 415 416 info.node = of_graph_get_remote_port(endpoint); 417 if (!info.node) 418 goto error; 419 420 of_node_put(endpoint); 421 422 ts->dsi = mipi_dsi_device_register_full(host, &info); 423 if (IS_ERR(ts->dsi)) { 424 dev_err(dev, "DSI device registration failed: %ld\n", 425 PTR_ERR(ts->dsi)); 426 return PTR_ERR(ts->dsi); 427 } 428 429 ts->base.dev = dev; 430 ts->base.funcs = &rpi_touchscreen_funcs; 431 432 /* This appears last, as it's what will unblock the DSI host 433 * driver's component bind function. 434 */ 435 ret = drm_panel_add(&ts->base); 436 if (ret) 437 return ret; 438 439 return 0; 440 441 error: 442 of_node_put(endpoint); 443 return -ENODEV; 444 } 445 446 static int 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 kfree(ts->dsi); 456 457 return 0; 458 } 459 460 static int rpi_touchscreen_dsi_probe(struct mipi_dsi_device *dsi) 461 { 462 int ret; 463 464 dsi->mode_flags = (MIPI_DSI_MODE_VIDEO | 465 MIPI_DSI_MODE_VIDEO_SYNC_PULSE | 466 MIPI_DSI_MODE_LPM); 467 dsi->format = MIPI_DSI_FMT_RGB888; 468 dsi->lanes = 1; 469 470 ret = mipi_dsi_attach(dsi); 471 472 if (ret) 473 dev_err(&dsi->dev, "failed to attach dsi to host: %d\n", ret); 474 475 return ret; 476 } 477 478 static struct mipi_dsi_driver rpi_touchscreen_dsi_driver = { 479 .driver.name = RPI_DSI_DRIVER_NAME, 480 .probe = rpi_touchscreen_dsi_probe, 481 }; 482 483 static const struct of_device_id rpi_touchscreen_of_ids[] = { 484 { .compatible = "raspberrypi,7inch-touchscreen-panel" }, 485 { } /* sentinel */ 486 }; 487 MODULE_DEVICE_TABLE(of, rpi_touchscreen_of_ids); 488 489 static struct i2c_driver rpi_touchscreen_driver = { 490 .driver = { 491 .name = "rpi_touchscreen", 492 .of_match_table = rpi_touchscreen_of_ids, 493 }, 494 .probe = rpi_touchscreen_probe, 495 .remove = rpi_touchscreen_remove, 496 }; 497 498 static int __init rpi_touchscreen_init(void) 499 { 500 mipi_dsi_driver_register(&rpi_touchscreen_dsi_driver); 501 return i2c_add_driver(&rpi_touchscreen_driver); 502 } 503 module_init(rpi_touchscreen_init); 504 505 static void __exit rpi_touchscreen_exit(void) 506 { 507 i2c_del_driver(&rpi_touchscreen_driver); 508 mipi_dsi_driver_unregister(&rpi_touchscreen_dsi_driver); 509 } 510 module_exit(rpi_touchscreen_exit); 511 512 MODULE_AUTHOR("Eric Anholt <eric@anholt.net>"); 513 MODULE_DESCRIPTION("Raspberry Pi 7-inch touchscreen driver"); 514 MODULE_LICENSE("GPL v2"); 515