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1/*2 * Copyright © 2016-2017 Broadcom3 *4 * This program is free software; you can redistribute it and/or modify5 * it under the terms of the GNU General Public License version 2 as6 * 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 a13 * copy of this software and associated documentation files (the "Software"),14 * to deal in the Software without restriction, including without limitation15 * 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 the17 * Software is furnished to do so, subject to the following conditions:18 *19 * The above copyright notice and this permission notice (including the20 * next paragraph) shall be included in all copies or substantial portions21 * of the Software.22 *23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR24 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,25 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL26 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER27 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING28 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER29 * 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 Toshiba36 * TC358762XBG DSI-DPI bridge, and an I2C-connected Atmel ATTINY88-MUR37 * controlling power management, the LCD PWM, and initial register38 * setup of the Tohsiba.39 *40 * This driver controls the TC358762 and ATTINY88, presenting a DSI41 * 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. */61enum 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 0x000485#define CLW_DPHYCONTRX 0x002086#define D0W_DPHYCONTRX 0x002487#define D1W_DPHYCONTRX 0x002888#define COM_DPHYCONTRX 0x003889#define CLW_CNTRL 0x004090#define D0W_CNTRL 0x004491#define D1W_CNTRL 0x004892#define DFTMODE_CNTRL 0x005493 94/* DSI PPI Layer Registers */95#define PPI_STARTPPI 0x010496#define PPI_BUSYPPI 0x010897#define PPI_LINEINITCNT 0x011098#define PPI_LPTXTIMECNT 0x011499#define PPI_CLS_ATMR 0x0140100#define PPI_D0S_ATMR 0x0144101#define PPI_D1S_ATMR 0x0148102#define PPI_D0S_CLRSIPOCOUNT 0x0164103#define PPI_D1S_CLRSIPOCOUNT 0x0168104#define CLS_PRE 0x0180105#define D0S_PRE 0x0184106#define D1S_PRE 0x0188107#define CLS_PREP 0x01A0108#define D0S_PREP 0x01A4109#define D1S_PREP 0x01A8110#define CLS_ZERO 0x01C0111#define D0S_ZERO 0x01C4112#define D1S_ZERO 0x01C8113#define PPI_CLRFLG 0x01E0114#define PPI_CLRSIPO 0x01E4115#define HSTIMEOUT 0x01F0116#define HSTIMEOUTENABLE 0x01F4117 118/* DSI Protocol Layer Registers */119#define DSI_STARTDSI 0x0204120#define DSI_BUSYDSI 0x0208121#define DSI_LANEENABLE 0x0210122# 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 0x0214127#define DSI_LANESTATUS1 0x0218128#define DSI_INTSTATUS 0x0220129#define DSI_INTMASK 0x0224130#define DSI_INTCLR 0x0228131#define DSI_LPTXTO 0x0230132#define DSI_MODE 0x0260133#define DSI_PAYLOAD0 0x0268134#define DSI_PAYLOAD1 0x026C135#define DSI_SHORTPKTDAT 0x0270136#define DSI_SHORTPKTREQ 0x0274137#define DSI_BTASTA 0x0278138#define DSI_BTACLR 0x027C139 140/* DSI General Registers */141#define DSIERRCNT 0x0300142#define DSISIGMOD 0x0304143 144/* DSI Application Layer Registers */145#define APLCTRL 0x0400146#define APLSTAT 0x0404147#define APLERR 0x0408148#define PWRMOD 0x040C149#define RDPKTLN 0x0410150#define PXLFMT 0x0414151#define MEMWRCMD 0x0418152 153/* LCDC/DPI Host Registers */154#define LCDCTRL 0x0420155#define HSR 0x0424156#define HDISPR 0x0428157#define VSR 0x042C158#define VDISPR 0x0430159#define VFUEN 0x0434160 161/* DBI-B Host Registers */162#define DBIBCTRL 0x0440163 164/* SPI Master Registers */165#define SPICMR 0x0450166#define SPITCR 0x0454167 168/* System Controller Registers */169#define SYSSTAT 0x0460170#define SYSCTRL 0x0464171#define SYSPLL1 0x0468172#define SYSPLL2 0x046C173#define SYSPLL3 0x0470174#define SYSPMCTRL 0x047C175 176/* GPIO Registers */177#define GPIOC 0x0480178#define GPIOO 0x0484179#define GPIOI 0x0488180 181/* I2C Registers */182#define I2CCLKCTRL 0x0490183 184/* Chip/Rev Registers */185#define IDREG 0x04A0186 187/* Debug Registers */188#define WCMDQUEUE 0x0500189#define RCMDQUEUE 0x0504190 191struct rpi_touchscreen {192 struct drm_panel base;193 struct mipi_dsi_device *dsi;194 struct i2c_client *i2c;195};196 197static const struct drm_display_mode rpi_touchscreen_modes[] = {198 {199 /* Modeline comes from the Raspberry Pi firmware, with HFP=1200 * 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 214static struct rpi_touchscreen *panel_to_ts(struct drm_panel *panel)215{216 return container_of(panel, struct rpi_touchscreen, base);217}218 219static int rpi_touchscreen_i2c_read(struct rpi_touchscreen *ts, u8 reg)220{221 return i2c_smbus_read_byte_data(ts->i2c, reg);222}223 224static 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 234static 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 250static 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 262static int rpi_touchscreen_noop(struct drm_panel *panel)263{264 return 0;265}266 267static 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 300static 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 source308 * firmware used for the panel. Runtime rotation309 * configuration will be supported using VC4's plane310 * orientation bits.311 */312 rpi_touchscreen_i2c_write(ts, REG_PORTA, BIT(2));313 314 return 0;315}316 317static 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 355static 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 363static 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 host435 * driver's component bind function.436 */437 drm_panel_add(&ts->base);438 439 return 0;440 441error:442 of_node_put(endpoint);443 return -ENODEV;444}445 446static 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 457static 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 475static struct mipi_dsi_driver rpi_touchscreen_dsi_driver = {476 .driver.name = RPI_DSI_DRIVER_NAME,477 .probe = rpi_touchscreen_dsi_probe,478};479 480static const struct of_device_id rpi_touchscreen_of_ids[] = {481 { .compatible = "raspberrypi,7inch-touchscreen-panel" },482 { } /* sentinel */483};484MODULE_DEVICE_TABLE(of, rpi_touchscreen_of_ids);485 486static 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 495static 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}500module_init(rpi_touchscreen_init);501 502static void __exit rpi_touchscreen_exit(void)503{504 i2c_del_driver(&rpi_touchscreen_driver);505 mipi_dsi_driver_unregister(&rpi_touchscreen_dsi_driver);506}507module_exit(rpi_touchscreen_exit);508 509MODULE_AUTHOR("Eric Anholt <eric@anholt.net>");510MODULE_DESCRIPTION("Raspberry Pi 7-inch touchscreen driver");511MODULE_LICENSE("GPL v2");512