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_panel.h> 57 #include <drm/drmP.h> 58 #include <drm/drm_crtc.h> 59 #include <drm/drm_mipi_dsi.h> 60 #include <drm/drm_panel.h> 61 62 #define RPI_DSI_DRIVER_NAME "rpi-ts-dsi" 63 64 /* I2C registers of the Atmel microcontroller. */ 65 enum REG_ADDR { 66 REG_ID = 0x80, 67 REG_PORTA, /* BIT(2) for horizontal flip, BIT(3) for vertical flip */ 68 REG_PORTB, 69 REG_PORTC, 70 REG_PORTD, 71 REG_POWERON, 72 REG_PWM, 73 REG_DDRA, 74 REG_DDRB, 75 REG_DDRC, 76 REG_DDRD, 77 REG_TEST, 78 REG_WR_ADDRL, 79 REG_WR_ADDRH, 80 REG_READH, 81 REG_READL, 82 REG_WRITEH, 83 REG_WRITEL, 84 REG_ID2, 85 }; 86 87 /* DSI D-PHY Layer Registers */ 88 #define D0W_DPHYCONTTX 0x0004 89 #define CLW_DPHYCONTRX 0x0020 90 #define D0W_DPHYCONTRX 0x0024 91 #define D1W_DPHYCONTRX 0x0028 92 #define COM_DPHYCONTRX 0x0038 93 #define CLW_CNTRL 0x0040 94 #define D0W_CNTRL 0x0044 95 #define D1W_CNTRL 0x0048 96 #define DFTMODE_CNTRL 0x0054 97 98 /* DSI PPI Layer Registers */ 99 #define PPI_STARTPPI 0x0104 100 #define PPI_BUSYPPI 0x0108 101 #define PPI_LINEINITCNT 0x0110 102 #define PPI_LPTXTIMECNT 0x0114 103 #define PPI_CLS_ATMR 0x0140 104 #define PPI_D0S_ATMR 0x0144 105 #define PPI_D1S_ATMR 0x0148 106 #define PPI_D0S_CLRSIPOCOUNT 0x0164 107 #define PPI_D1S_CLRSIPOCOUNT 0x0168 108 #define CLS_PRE 0x0180 109 #define D0S_PRE 0x0184 110 #define D1S_PRE 0x0188 111 #define CLS_PREP 0x01A0 112 #define D0S_PREP 0x01A4 113 #define D1S_PREP 0x01A8 114 #define CLS_ZERO 0x01C0 115 #define D0S_ZERO 0x01C4 116 #define D1S_ZERO 0x01C8 117 #define PPI_CLRFLG 0x01E0 118 #define PPI_CLRSIPO 0x01E4 119 #define HSTIMEOUT 0x01F0 120 #define HSTIMEOUTENABLE 0x01F4 121 122 /* DSI Protocol Layer Registers */ 123 #define DSI_STARTDSI 0x0204 124 #define DSI_BUSYDSI 0x0208 125 #define DSI_LANEENABLE 0x0210 126 # define DSI_LANEENABLE_CLOCK BIT(0) 127 # define DSI_LANEENABLE_D0 BIT(1) 128 # define DSI_LANEENABLE_D1 BIT(2) 129 130 #define DSI_LANESTATUS0 0x0214 131 #define DSI_LANESTATUS1 0x0218 132 #define DSI_INTSTATUS 0x0220 133 #define DSI_INTMASK 0x0224 134 #define DSI_INTCLR 0x0228 135 #define DSI_LPTXTO 0x0230 136 #define DSI_MODE 0x0260 137 #define DSI_PAYLOAD0 0x0268 138 #define DSI_PAYLOAD1 0x026C 139 #define DSI_SHORTPKTDAT 0x0270 140 #define DSI_SHORTPKTREQ 0x0274 141 #define DSI_BTASTA 0x0278 142 #define DSI_BTACLR 0x027C 143 144 /* DSI General Registers */ 145 #define DSIERRCNT 0x0300 146 #define DSISIGMOD 0x0304 147 148 /* DSI Application Layer Registers */ 149 #define APLCTRL 0x0400 150 #define APLSTAT 0x0404 151 #define APLERR 0x0408 152 #define PWRMOD 0x040C 153 #define RDPKTLN 0x0410 154 #define PXLFMT 0x0414 155 #define MEMWRCMD 0x0418 156 157 /* LCDC/DPI Host Registers */ 158 #define LCDCTRL 0x0420 159 #define HSR 0x0424 160 #define HDISPR 0x0428 161 #define VSR 0x042C 162 #define VDISPR 0x0430 163 #define VFUEN 0x0434 164 165 /* DBI-B Host Registers */ 166 #define DBIBCTRL 0x0440 167 168 /* SPI Master Registers */ 169 #define SPICMR 0x0450 170 #define SPITCR 0x0454 171 172 /* System Controller Registers */ 173 #define SYSSTAT 0x0460 174 #define SYSCTRL 0x0464 175 #define SYSPLL1 0x0468 176 #define SYSPLL2 0x046C 177 #define SYSPLL3 0x0470 178 #define SYSPMCTRL 0x047C 179 180 /* GPIO Registers */ 181 #define GPIOC 0x0480 182 #define GPIOO 0x0484 183 #define GPIOI 0x0488 184 185 /* I2C Registers */ 186 #define I2CCLKCTRL 0x0490 187 188 /* Chip/Rev Registers */ 189 #define IDREG 0x04A0 190 191 /* Debug Registers */ 192 #define WCMDQUEUE 0x0500 193 #define RCMDQUEUE 0x0504 194 195 struct rpi_touchscreen { 196 struct drm_panel base; 197 struct mipi_dsi_device *dsi; 198 struct i2c_client *i2c; 199 }; 200 201 static const struct drm_display_mode rpi_touchscreen_modes[] = { 202 { 203 /* Modeline comes from the Raspberry Pi firmware, with HFP=1 204 * plugged in and clock re-computed from that. 205 */ 206 .clock = 25979400 / 1000, 207 .hdisplay = 800, 208 .hsync_start = 800 + 1, 209 .hsync_end = 800 + 1 + 2, 210 .htotal = 800 + 1 + 2 + 46, 211 .vdisplay = 480, 212 .vsync_start = 480 + 7, 213 .vsync_end = 480 + 7 + 2, 214 .vtotal = 480 + 7 + 2 + 21, 215 .vrefresh = 60, 216 }, 217 }; 218 219 static struct rpi_touchscreen *panel_to_ts(struct drm_panel *panel) 220 { 221 return container_of(panel, struct rpi_touchscreen, base); 222 } 223 224 static int rpi_touchscreen_i2c_read(struct rpi_touchscreen *ts, u8 reg) 225 { 226 return i2c_smbus_read_byte_data(ts->i2c, reg); 227 } 228 229 static void rpi_touchscreen_i2c_write(struct rpi_touchscreen *ts, 230 u8 reg, u8 val) 231 { 232 int ret; 233 234 ret = i2c_smbus_write_byte_data(ts->i2c, reg, val); 235 if (ret) 236 dev_err(&ts->dsi->dev, "I2C write failed: %d\n", ret); 237 } 238 239 static int rpi_touchscreen_write(struct rpi_touchscreen *ts, u16 reg, u32 val) 240 { 241 u8 msg[] = { 242 reg, 243 reg >> 8, 244 val, 245 val >> 8, 246 val >> 16, 247 val >> 24, 248 }; 249 250 mipi_dsi_generic_write(ts->dsi, msg, sizeof(msg)); 251 252 return 0; 253 } 254 255 static int rpi_touchscreen_disable(struct drm_panel *panel) 256 { 257 struct rpi_touchscreen *ts = panel_to_ts(panel); 258 259 rpi_touchscreen_i2c_write(ts, REG_PWM, 0); 260 261 rpi_touchscreen_i2c_write(ts, REG_POWERON, 0); 262 udelay(1); 263 264 return 0; 265 } 266 267 static int rpi_touchscreen_noop(struct drm_panel *panel) 268 { 269 return 0; 270 } 271 272 static int rpi_touchscreen_enable(struct drm_panel *panel) 273 { 274 struct rpi_touchscreen *ts = panel_to_ts(panel); 275 int i; 276 277 rpi_touchscreen_i2c_write(ts, REG_POWERON, 1); 278 /* Wait for nPWRDWN to go low to indicate poweron is done. */ 279 for (i = 0; i < 100; i++) { 280 if (rpi_touchscreen_i2c_read(ts, REG_PORTB) & 1) 281 break; 282 } 283 284 rpi_touchscreen_write(ts, DSI_LANEENABLE, 285 DSI_LANEENABLE_CLOCK | 286 DSI_LANEENABLE_D0); 287 rpi_touchscreen_write(ts, PPI_D0S_CLRSIPOCOUNT, 0x05); 288 rpi_touchscreen_write(ts, PPI_D1S_CLRSIPOCOUNT, 0x05); 289 rpi_touchscreen_write(ts, PPI_D0S_ATMR, 0x00); 290 rpi_touchscreen_write(ts, PPI_D1S_ATMR, 0x00); 291 rpi_touchscreen_write(ts, PPI_LPTXTIMECNT, 0x03); 292 293 rpi_touchscreen_write(ts, SPICMR, 0x00); 294 rpi_touchscreen_write(ts, LCDCTRL, 0x00100150); 295 rpi_touchscreen_write(ts, SYSCTRL, 0x040f); 296 msleep(100); 297 298 rpi_touchscreen_write(ts, PPI_STARTPPI, 0x01); 299 rpi_touchscreen_write(ts, DSI_STARTDSI, 0x01); 300 msleep(100); 301 302 /* Turn on the backlight. */ 303 rpi_touchscreen_i2c_write(ts, REG_PWM, 255); 304 305 /* Default to the same orientation as the closed source 306 * firmware used for the panel. Runtime rotation 307 * configuration will be supported using VC4's plane 308 * orientation bits. 309 */ 310 rpi_touchscreen_i2c_write(ts, REG_PORTA, BIT(2)); 311 312 return 0; 313 } 314 315 static int rpi_touchscreen_get_modes(struct drm_panel *panel) 316 { 317 struct drm_connector *connector = panel->connector; 318 struct drm_device *drm = panel->drm; 319 unsigned int i, num = 0; 320 static const u32 bus_format = MEDIA_BUS_FMT_RGB888_1X24; 321 322 for (i = 0; i < ARRAY_SIZE(rpi_touchscreen_modes); i++) { 323 const struct drm_display_mode *m = &rpi_touchscreen_modes[i]; 324 struct drm_display_mode *mode; 325 326 mode = drm_mode_duplicate(drm, m); 327 if (!mode) { 328 dev_err(drm->dev, "failed to add mode %ux%u@%u\n", 329 m->hdisplay, m->vdisplay, m->vrefresh); 330 continue; 331 } 332 333 mode->type |= DRM_MODE_TYPE_DRIVER; 334 335 if (i == 0) 336 mode->type |= DRM_MODE_TYPE_PREFERRED; 337 338 drm_mode_set_name(mode); 339 340 drm_mode_probed_add(connector, mode); 341 num++; 342 } 343 344 connector->display_info.bpc = 8; 345 connector->display_info.width_mm = 154; 346 connector->display_info.height_mm = 86; 347 drm_display_info_set_bus_formats(&connector->display_info, 348 &bus_format, 1); 349 350 return num; 351 } 352 353 static const struct drm_panel_funcs rpi_touchscreen_funcs = { 354 .disable = rpi_touchscreen_disable, 355 .unprepare = rpi_touchscreen_noop, 356 .prepare = rpi_touchscreen_noop, 357 .enable = rpi_touchscreen_enable, 358 .get_modes = rpi_touchscreen_get_modes, 359 }; 360 361 static int rpi_touchscreen_probe(struct i2c_client *i2c, 362 const struct i2c_device_id *id) 363 { 364 struct device *dev = &i2c->dev; 365 struct rpi_touchscreen *ts; 366 struct device_node *endpoint, *dsi_host_node; 367 struct mipi_dsi_host *host; 368 int ret, ver; 369 struct mipi_dsi_device_info info = { 370 .type = RPI_DSI_DRIVER_NAME, 371 .channel = 0, 372 .node = NULL, 373 }; 374 375 ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL); 376 if (!ts) 377 return -ENOMEM; 378 379 i2c_set_clientdata(i2c, ts); 380 381 ts->i2c = i2c; 382 383 ver = rpi_touchscreen_i2c_read(ts, REG_ID); 384 if (ver < 0) { 385 dev_err(dev, "Atmel I2C read failed: %d\n", ver); 386 return -ENODEV; 387 } 388 389 switch (ver) { 390 case 0xde: /* ver 1 */ 391 case 0xc3: /* ver 2 */ 392 break; 393 default: 394 dev_err(dev, "Unknown Atmel firmware revision: 0x%02x\n", ver); 395 return -ENODEV; 396 } 397 398 /* Turn off at boot, so we can cleanly sequence powering on. */ 399 rpi_touchscreen_i2c_write(ts, REG_POWERON, 0); 400 401 /* Look up the DSI host. It needs to probe before we do. */ 402 endpoint = of_graph_get_next_endpoint(dev->of_node, NULL); 403 dsi_host_node = of_graph_get_remote_port_parent(endpoint); 404 host = of_find_mipi_dsi_host_by_node(dsi_host_node); 405 of_node_put(dsi_host_node); 406 if (!host) { 407 of_node_put(endpoint); 408 return -EPROBE_DEFER; 409 } 410 411 info.node = of_graph_get_remote_port(endpoint); 412 of_node_put(endpoint); 413 414 ts->dsi = mipi_dsi_device_register_full(host, &info); 415 if (IS_ERR(ts->dsi)) { 416 dev_err(dev, "DSI device registration failed: %ld\n", 417 PTR_ERR(ts->dsi)); 418 return PTR_ERR(ts->dsi); 419 } 420 421 ts->base.dev = dev; 422 ts->base.funcs = &rpi_touchscreen_funcs; 423 424 /* This appears last, as it's what will unblock the DSI host 425 * driver's component bind function. 426 */ 427 ret = drm_panel_add(&ts->base); 428 if (ret) 429 return ret; 430 431 return 0; 432 } 433 434 static int rpi_touchscreen_remove(struct i2c_client *i2c) 435 { 436 struct rpi_touchscreen *ts = i2c_get_clientdata(i2c); 437 438 mipi_dsi_detach(ts->dsi); 439 440 drm_panel_remove(&ts->base); 441 442 mipi_dsi_device_unregister(ts->dsi); 443 kfree(ts->dsi); 444 445 return 0; 446 } 447 448 static int rpi_touchscreen_dsi_probe(struct mipi_dsi_device *dsi) 449 { 450 int ret; 451 452 dsi->mode_flags = (MIPI_DSI_MODE_VIDEO | 453 MIPI_DSI_MODE_VIDEO_SYNC_PULSE | 454 MIPI_DSI_MODE_LPM); 455 dsi->format = MIPI_DSI_FMT_RGB888; 456 dsi->lanes = 1; 457 458 ret = mipi_dsi_attach(dsi); 459 460 if (ret) 461 dev_err(&dsi->dev, "failed to attach dsi to host: %d\n", ret); 462 463 return ret; 464 } 465 466 static struct mipi_dsi_driver rpi_touchscreen_dsi_driver = { 467 .driver.name = RPI_DSI_DRIVER_NAME, 468 .probe = rpi_touchscreen_dsi_probe, 469 }; 470 471 static const struct of_device_id rpi_touchscreen_of_ids[] = { 472 { .compatible = "raspberrypi,7inch-touchscreen-panel" }, 473 { } /* sentinel */ 474 }; 475 MODULE_DEVICE_TABLE(of, rpi_touchscreen_of_ids); 476 477 static struct i2c_driver rpi_touchscreen_driver = { 478 .driver = { 479 .name = "rpi_touchscreen", 480 .of_match_table = rpi_touchscreen_of_ids, 481 }, 482 .probe = rpi_touchscreen_probe, 483 .remove = rpi_touchscreen_remove, 484 }; 485 486 static int __init rpi_touchscreen_init(void) 487 { 488 mipi_dsi_driver_register(&rpi_touchscreen_dsi_driver); 489 return i2c_add_driver(&rpi_touchscreen_driver); 490 } 491 module_init(rpi_touchscreen_init); 492 493 static void __exit rpi_touchscreen_exit(void) 494 { 495 i2c_del_driver(&rpi_touchscreen_driver); 496 mipi_dsi_driver_unregister(&rpi_touchscreen_dsi_driver); 497 } 498 module_exit(rpi_touchscreen_exit); 499 500 MODULE_AUTHOR("Eric Anholt <eric@anholt.net>"); 501 MODULE_DESCRIPTION("Raspberry Pi 7-inch touchscreen driver"); 502 MODULE_LICENSE("GPL v2"); 503