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1// SPDX-License-Identifier: GPL-2.0+2// handle au0828 IR remotes via linux kernel input layer.3//4// Copyright (c) 2014 Mauro Carvalho Chehab <mchehab@samsung.com>5// Copyright (c) 2014 Samsung Electronics Co., Ltd.6//7// Based on em28xx-input.c.8 9#include "au0828.h"10 11#include <linux/module.h>12#include <linux/init.h>13#include <linux/delay.h>14#include <linux/interrupt.h>15#include <linux/usb.h>16#include <linux/slab.h>17#include <media/rc-core.h>18 19static int disable_ir;20module_param(disable_ir, int, 0444);21MODULE_PARM_DESC(disable_ir, "disable infrared remote support");22 23struct au0828_rc {24 struct au0828_dev *dev;25 struct rc_dev *rc;26 char name[32];27 char phys[32];28 29 /* poll decoder */30 int polling;31 struct delayed_work work;32 33 /* i2c slave address of external device (if used) */34 u16 i2c_dev_addr;35 36 int (*get_key_i2c)(struct au0828_rc *ir);37};38 39/*40 * AU8522 has a builtin IR receiver. Add functions to get IR from it41 */42 43static int au8522_rc_write(struct au0828_rc *ir, u16 reg, u8 data)44{45 int rc;46 char buf[] = { (reg >> 8) | 0x80, reg & 0xff, data };47 struct i2c_msg msg = { .addr = ir->i2c_dev_addr, .flags = 0,48 .buf = buf, .len = sizeof(buf) };49 50 rc = i2c_transfer(ir->dev->i2c_client.adapter, &msg, 1);51 52 if (rc < 0)53 return rc;54 55 return (rc == 1) ? 0 : -EIO;56}57 58static int au8522_rc_read(struct au0828_rc *ir, u16 reg, int val,59 char *buf, int size)60{61 int rc;62 char obuf[3];63 struct i2c_msg msg[2] = { { .addr = ir->i2c_dev_addr, .flags = 0,64 .buf = obuf, .len = 2 },65 { .addr = ir->i2c_dev_addr, .flags = I2C_M_RD,66 .buf = buf, .len = size } };67 68 obuf[0] = 0x40 | reg >> 8;69 obuf[1] = reg & 0xff;70 if (val >= 0) {71 obuf[2] = val;72 msg[0].len++;73 }74 75 rc = i2c_transfer(ir->dev->i2c_client.adapter, msg, 2);76 77 if (rc < 0)78 return rc;79 80 return (rc == 2) ? 0 : -EIO;81}82 83static int au8522_rc_andor(struct au0828_rc *ir, u16 reg, u8 mask, u8 value)84{85 int rc;86 char buf, oldbuf;87 88 rc = au8522_rc_read(ir, reg, -1, &buf, 1);89 if (rc < 0)90 return rc;91 92 oldbuf = buf;93 buf = (buf & ~mask) | (value & mask);94 95 /* Nothing to do, just return */96 if (buf == oldbuf)97 return 0;98 99 return au8522_rc_write(ir, reg, buf);100}101 102#define au8522_rc_set(ir, reg, bit) au8522_rc_andor(ir, (reg), (bit), (bit))103#define au8522_rc_clear(ir, reg, bit) au8522_rc_andor(ir, (reg), (bit), 0)104 105/* Remote Controller time units */106 107#define AU8522_UNIT 200 /* us */108#define NEC_START_SPACE (4500 / AU8522_UNIT)109#define NEC_START_PULSE (563 * 16)110#define RC5_START_SPACE (4 * AU8522_UNIT)111#define RC5_START_PULSE 889112 113static int au0828_get_key_au8522(struct au0828_rc *ir)114{115 unsigned char buf[40];116 struct ir_raw_event rawir = {};117 int i, j, rc;118 int prv_bit, bit, width;119 bool first = true;120 121 /* do nothing if device is disconnected */122 if (test_bit(DEV_DISCONNECTED, &ir->dev->dev_state))123 return 0;124 125 /* Check IR int */126 rc = au8522_rc_read(ir, 0xe1, -1, buf, 1);127 if (rc < 0 || !(buf[0] & (1 << 4))) {128 /* Be sure that IR is enabled */129 au8522_rc_set(ir, 0xe0, 1 << 4);130 return 0;131 }132 133 /* Something arrived. Get the data */134 rc = au8522_rc_read(ir, 0xe3, 0x11, buf, sizeof(buf));135 136 137 if (rc < 0)138 return rc;139 140 /* Disable IR */141 au8522_rc_clear(ir, 0xe0, 1 << 4);142 143 /* Enable IR */144 au8522_rc_set(ir, 0xe0, 1 << 4);145 146 dprintk(16, "RC data received: %*ph\n", 40, buf);147 148 prv_bit = (buf[0] >> 7) & 0x01;149 width = 0;150 for (i = 0; i < sizeof(buf); i++) {151 for (j = 7; j >= 0; j--) {152 bit = (buf[i] >> j) & 0x01;153 if (bit == prv_bit) {154 width++;155 continue;156 }157 158 /*159 * Fix an au8522 bug: the first pulse event160 * is lost. So, we need to fake it, based on the161 * protocol. That means that not all raw decoders162 * will work, as we need to add a hack for each163 * protocol, based on the first space.164 * So, we only support RC5 and NEC.165 */166 167 if (first) {168 first = false;169 170 rawir.pulse = true;171 if (width > NEC_START_SPACE - 2 &&172 width < NEC_START_SPACE + 2) {173 /* NEC protocol */174 rawir.duration = NEC_START_PULSE;175 dprintk(16, "Storing NEC start %s with duration %d",176 rawir.pulse ? "pulse" : "space",177 rawir.duration);178 } else {179 /* RC5 protocol */180 rawir.duration = RC5_START_PULSE;181 dprintk(16, "Storing RC5 start %s with duration %d",182 rawir.pulse ? "pulse" : "space",183 rawir.duration);184 }185 ir_raw_event_store(ir->rc, &rawir);186 }187 188 rawir.pulse = prv_bit ? false : true;189 rawir.duration = AU8522_UNIT * width;190 dprintk(16, "Storing %s with duration %d",191 rawir.pulse ? "pulse" : "space",192 rawir.duration);193 ir_raw_event_store(ir->rc, &rawir);194 195 width = 1;196 prv_bit = bit;197 }198 }199 200 rawir.pulse = prv_bit ? false : true;201 rawir.duration = AU8522_UNIT * width;202 dprintk(16, "Storing end %s with duration %d",203 rawir.pulse ? "pulse" : "space",204 rawir.duration);205 ir_raw_event_store(ir->rc, &rawir);206 207 ir_raw_event_handle(ir->rc);208 209 return 1;210}211 212/*213 * Generic IR code214 */215 216static void au0828_rc_work(struct work_struct *work)217{218 struct au0828_rc *ir = container_of(work, struct au0828_rc, work.work);219 int rc;220 221 rc = ir->get_key_i2c(ir);222 if (rc < 0)223 pr_info("Error while getting RC scancode\n");224 225 schedule_delayed_work(&ir->work, msecs_to_jiffies(ir->polling));226}227 228static int au0828_rc_start(struct rc_dev *rc)229{230 struct au0828_rc *ir = rc->priv;231 232 INIT_DELAYED_WORK(&ir->work, au0828_rc_work);233 234 /* Enable IR */235 au8522_rc_set(ir, 0xe0, 1 << 4);236 237 schedule_delayed_work(&ir->work, msecs_to_jiffies(ir->polling));238 239 return 0;240}241 242static void au0828_rc_stop(struct rc_dev *rc)243{244 struct au0828_rc *ir = rc->priv;245 246 cancel_delayed_work_sync(&ir->work);247 248 /* do nothing if device is disconnected */249 if (!test_bit(DEV_DISCONNECTED, &ir->dev->dev_state)) {250 /* Disable IR */251 au8522_rc_clear(ir, 0xe0, 1 << 4);252 }253}254 255static int au0828_probe_i2c_ir(struct au0828_dev *dev)256{257 int i = 0;258 static const unsigned short addr_list[] = {259 0x47, I2C_CLIENT_END260 };261 262 while (addr_list[i] != I2C_CLIENT_END) {263 if (i2c_probe_func_quick_read(dev->i2c_client.adapter,264 addr_list[i]) == 1)265 return addr_list[i];266 i++;267 }268 269 return -ENODEV;270}271 272int au0828_rc_register(struct au0828_dev *dev)273{274 struct au0828_rc *ir;275 struct rc_dev *rc;276 int err = -ENOMEM;277 u16 i2c_rc_dev_addr = 0;278 279 if (!dev->board.has_ir_i2c || disable_ir)280 return 0;281 282 i2c_rc_dev_addr = au0828_probe_i2c_ir(dev);283 if (!i2c_rc_dev_addr)284 return -ENODEV;285 286 ir = kzalloc(sizeof(*ir), GFP_KERNEL);287 rc = rc_allocate_device(RC_DRIVER_IR_RAW);288 if (!ir || !rc)289 goto error;290 291 /* record handles to ourself */292 ir->dev = dev;293 dev->ir = ir;294 ir->rc = rc;295 296 rc->priv = ir;297 rc->open = au0828_rc_start;298 rc->close = au0828_rc_stop;299 300 if (dev->board.has_ir_i2c) { /* external i2c device */301 switch (dev->boardnr) {302 case AU0828_BOARD_HAUPPAUGE_HVR950Q:303 rc->map_name = RC_MAP_HAUPPAUGE;304 ir->get_key_i2c = au0828_get_key_au8522;305 break;306 default:307 err = -ENODEV;308 goto error;309 }310 311 ir->i2c_dev_addr = i2c_rc_dev_addr;312 }313 314 /* This is how often we ask the chip for IR information */315 ir->polling = 100; /* ms */316 317 /* init input device */318 snprintf(ir->name, sizeof(ir->name), "au0828 IR (%s)",319 dev->board.name);320 321 usb_make_path(dev->usbdev, ir->phys, sizeof(ir->phys));322 strlcat(ir->phys, "/input0", sizeof(ir->phys));323 324 rc->device_name = ir->name;325 rc->input_phys = ir->phys;326 rc->input_id.bustype = BUS_USB;327 rc->input_id.version = 1;328 rc->input_id.vendor = le16_to_cpu(dev->usbdev->descriptor.idVendor);329 rc->input_id.product = le16_to_cpu(dev->usbdev->descriptor.idProduct);330 rc->dev.parent = &dev->usbdev->dev;331 rc->driver_name = "au0828-input";332 rc->allowed_protocols = RC_PROTO_BIT_NEC | RC_PROTO_BIT_NECX |333 RC_PROTO_BIT_NEC32 | RC_PROTO_BIT_RC5;334 335 /* all done */336 err = rc_register_device(rc);337 if (err)338 goto error;339 340 pr_info("Remote controller %s initialized\n", ir->name);341 342 return 0;343 344error:345 dev->ir = NULL;346 rc_free_device(rc);347 kfree(ir);348 return err;349}350 351void au0828_rc_unregister(struct au0828_dev *dev)352{353 struct au0828_rc *ir = dev->ir;354 355 /* skip detach on non attached boards */356 if (!ir)357 return;358 359 rc_unregister_device(ir->rc);360 361 /* done */362 kfree(ir);363 dev->ir = NULL;364}365 366int au0828_rc_suspend(struct au0828_dev *dev)367{368 struct au0828_rc *ir = dev->ir;369 370 if (!ir)371 return 0;372 373 pr_info("Stopping RC\n");374 375 cancel_delayed_work_sync(&ir->work);376 377 /* Disable IR */378 au8522_rc_clear(ir, 0xe0, 1 << 4);379 380 return 0;381}382 383int au0828_rc_resume(struct au0828_dev *dev)384{385 struct au0828_rc *ir = dev->ir;386 387 if (!ir)388 return 0;389 390 pr_info("Restarting RC\n");391 392 /* Enable IR */393 au8522_rc_set(ir, 0xe0, 1 << 4);394 395 schedule_delayed_work(&ir->work, msecs_to_jiffies(ir->polling));396 397 return 0;398}399