linux/drivers/media/radio/si4713/radio-usb-si4713.c
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   1/*
   2 * Copyright 2013 Cisco Systems, Inc. and/or its affiliates.
   3 * All rights reserved.
   4 *
   5 * This program is free software; you may redistribute it and/or modify
   6 * it under the terms of the GNU General Public License as published by
   7 * the Free Software Foundation; version 2 of the License.
   8 *
   9 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  10 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  11 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  12 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  13 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  14 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  15 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  16 * SOFTWARE.
  17 */
  18
  19/* kernel includes */
  20#include <linux/kernel.h>
  21#include <linux/module.h>
  22#include <linux/usb.h>
  23#include <linux/init.h>
  24#include <linux/slab.h>
  25#include <linux/input.h>
  26#include <linux/mutex.h>
  27#include <linux/i2c.h>
  28/* V4l includes */
  29#include <linux/videodev2.h>
  30#include <media/v4l2-common.h>
  31#include <media/v4l2-device.h>
  32#include <media/v4l2-ioctl.h>
  33#include <media/v4l2-event.h>
  34#include <media/si4713.h>
  35
  36#include "si4713.h"
  37
  38/* driver and module definitions */
  39MODULE_AUTHOR("Dinesh Ram <dinesh.ram@cern.ch>");
  40MODULE_DESCRIPTION("Si4713 FM Transmitter USB driver");
  41MODULE_LICENSE("GPL v2");
  42
  43/* The Device announces itself as Cygnal Integrated Products, Inc. */
  44#define USB_SI4713_VENDOR               0x10c4
  45#define USB_SI4713_PRODUCT              0x8244
  46
  47#define BUFFER_LENGTH                   64
  48#define USB_TIMEOUT                     1000
  49#define USB_RESP_TIMEOUT                50000
  50
  51/* USB Device ID List */
  52static struct usb_device_id usb_si4713_usb_device_table[] = {
  53        {USB_DEVICE_AND_INTERFACE_INFO(USB_SI4713_VENDOR, USB_SI4713_PRODUCT,
  54                                                        USB_CLASS_HID, 0, 0) },
  55        { }                                             /* Terminating entry */
  56};
  57
  58MODULE_DEVICE_TABLE(usb, usb_si4713_usb_device_table);
  59
  60struct si4713_usb_device {
  61        struct usb_device       *usbdev;
  62        struct usb_interface    *intf;
  63        struct video_device     vdev;
  64        struct v4l2_device      v4l2_dev;
  65        struct v4l2_subdev      *v4l2_subdev;
  66        struct mutex            lock;
  67        struct i2c_adapter      i2c_adapter;
  68
  69        u8                      *buffer;
  70};
  71
  72static inline struct si4713_usb_device *to_si4713_dev(struct v4l2_device *v4l2_dev)
  73{
  74        return container_of(v4l2_dev, struct si4713_usb_device, v4l2_dev);
  75}
  76
  77static int vidioc_querycap(struct file *file, void *priv,
  78                                        struct v4l2_capability *v)
  79{
  80        struct si4713_usb_device *radio = video_drvdata(file);
  81
  82        strlcpy(v->driver, "radio-usb-si4713", sizeof(v->driver));
  83        strlcpy(v->card, "Si4713 FM Transmitter", sizeof(v->card));
  84        usb_make_path(radio->usbdev, v->bus_info, sizeof(v->bus_info));
  85        v->device_caps = V4L2_CAP_MODULATOR | V4L2_CAP_RDS_OUTPUT;
  86        v->capabilities = v->device_caps | V4L2_CAP_DEVICE_CAPS;
  87
  88        return 0;
  89}
  90
  91static int vidioc_g_modulator(struct file *file, void *priv,
  92                                struct v4l2_modulator *vm)
  93{
  94        struct si4713_usb_device *radio = video_drvdata(file);
  95
  96        return v4l2_subdev_call(radio->v4l2_subdev, tuner, g_modulator, vm);
  97}
  98
  99static int vidioc_s_modulator(struct file *file, void *priv,
 100                                const struct v4l2_modulator *vm)
 101{
 102        struct si4713_usb_device *radio = video_drvdata(file);
 103
 104        return v4l2_subdev_call(radio->v4l2_subdev, tuner, s_modulator, vm);
 105}
 106
 107static int vidioc_s_frequency(struct file *file, void *priv,
 108                                const struct v4l2_frequency *vf)
 109{
 110        struct si4713_usb_device *radio = video_drvdata(file);
 111
 112        return v4l2_subdev_call(radio->v4l2_subdev, tuner, s_frequency, vf);
 113}
 114
 115static int vidioc_g_frequency(struct file *file, void *priv,
 116                                struct v4l2_frequency *vf)
 117{
 118        struct si4713_usb_device *radio = video_drvdata(file);
 119
 120        return v4l2_subdev_call(radio->v4l2_subdev, tuner, g_frequency, vf);
 121}
 122
 123static const struct v4l2_ioctl_ops usb_si4713_ioctl_ops = {
 124        .vidioc_querycap          = vidioc_querycap,
 125        .vidioc_g_modulator       = vidioc_g_modulator,
 126        .vidioc_s_modulator       = vidioc_s_modulator,
 127        .vidioc_g_frequency       = vidioc_g_frequency,
 128        .vidioc_s_frequency       = vidioc_s_frequency,
 129        .vidioc_log_status        = v4l2_ctrl_log_status,
 130        .vidioc_subscribe_event   = v4l2_ctrl_subscribe_event,
 131        .vidioc_unsubscribe_event = v4l2_event_unsubscribe,
 132};
 133
 134/* File system interface */
 135static const struct v4l2_file_operations usb_si4713_fops = {
 136        .owner          = THIS_MODULE,
 137        .open           = v4l2_fh_open,
 138        .release        = v4l2_fh_release,
 139        .poll           = v4l2_ctrl_poll,
 140        .unlocked_ioctl = video_ioctl2,
 141};
 142
 143static void usb_si4713_video_device_release(struct v4l2_device *v4l2_dev)
 144{
 145        struct si4713_usb_device *radio = to_si4713_dev(v4l2_dev);
 146        struct i2c_adapter *adapter = &radio->i2c_adapter;
 147
 148        i2c_del_adapter(adapter);
 149        v4l2_device_unregister(&radio->v4l2_dev);
 150        kfree(radio->buffer);
 151        kfree(radio);
 152}
 153
 154/*
 155 * This command sequence emulates the behaviour of the Windows driver.
 156 * The structure of these commands was determined by sniffing the
 157 * usb traffic of the device during startup.
 158 * Most likely, these commands make some queries to the device.
 159 * Commands are sent to enquire parameters like the bus mode,
 160 * component revision, boot mode, the device serial number etc.
 161 *
 162 * These commands are necessary to be sent in this order during startup.
 163 * The device fails to powerup if these commands are not sent.
 164 *
 165 * The complete list of startup commands is given in the start_seq table below.
 166 */
 167static int si4713_send_startup_command(struct si4713_usb_device *radio)
 168{
 169        unsigned long until_jiffies = jiffies + usecs_to_jiffies(USB_RESP_TIMEOUT) + 1;
 170        u8 *buffer = radio->buffer;
 171        int retval;
 172
 173        /* send the command */
 174        retval = usb_control_msg(radio->usbdev, usb_sndctrlpipe(radio->usbdev, 0),
 175                                        0x09, 0x21, 0x033f, 0, radio->buffer,
 176                                        BUFFER_LENGTH, USB_TIMEOUT);
 177        if (retval < 0)
 178                return retval;
 179
 180        for (;;) {
 181                /* receive the response */
 182                retval = usb_control_msg(radio->usbdev, usb_rcvctrlpipe(radio->usbdev, 0),
 183                                0x01, 0xa1, 0x033f, 0, radio->buffer,
 184                                BUFFER_LENGTH, USB_TIMEOUT);
 185                if (retval < 0)
 186                        return retval;
 187                if (!radio->buffer[1]) {
 188                        /* USB traffic sniffing showed that some commands require
 189                         * additional checks. */
 190                        switch (buffer[1]) {
 191                        case 0x32:
 192                                if (radio->buffer[2] == 0)
 193                                        return 0;
 194                                break;
 195                        case 0x14:
 196                        case 0x12:
 197                                if (radio->buffer[2] & SI4713_CTS)
 198                                        return 0;
 199                                break;
 200                        case 0x06:
 201                                if ((radio->buffer[2] & SI4713_CTS) && radio->buffer[9] == 0x08)
 202                                        return 0;
 203                                break;
 204                        default:
 205                                return 0;
 206                        }
 207                }
 208                if (time_is_before_jiffies(until_jiffies))
 209                        return -EIO;
 210                msleep(3);
 211        }
 212
 213        return retval;
 214}
 215
 216struct si4713_start_seq_table {
 217        int len;
 218        u8 payload[8];
 219};
 220
 221/*
 222 * Some of the startup commands that could be recognized are :
 223 * (0x03): Get serial number of the board (Response : CB000-00-00)
 224 * (0x06, 0x03, 0x03, 0x08, 0x01, 0x0f) : Get Component revision
 225 */
 226static const struct si4713_start_seq_table start_seq[] = {
 227
 228        { 1, { 0x03 } },
 229        { 2, { 0x32, 0x7f } },
 230        { 6, { 0x06, 0x03, 0x03, 0x08, 0x01, 0x0f } },
 231        { 2, { 0x14, 0x02 } },
 232        { 2, { 0x09, 0x90 } },
 233        { 3, { 0x08, 0x90, 0xfa } },
 234        { 2, { 0x36, 0x01 } },
 235        { 2, { 0x05, 0x03 } },
 236        { 7, { 0x06, 0x00, 0x06, 0x0e, 0x01, 0x0f, 0x05 } },
 237        { 1, { 0x12 } },
 238        /* Commands that are sent after pressing the 'Initialize'
 239                button in the windows application */
 240        { 1, { 0x03 } },
 241        { 1, { 0x01 } },
 242        { 2, { 0x09, 0x90 } },
 243        { 3, { 0x08, 0x90, 0xfa } },
 244        { 1, { 0x34 } },
 245        { 2, { 0x35, 0x01 } },
 246        { 2, { 0x36, 0x01 } },
 247        { 2, { 0x30, 0x09 } },
 248        { 4, { 0x30, 0x06, 0x00, 0xe2 } },
 249        { 3, { 0x31, 0x01, 0x30 } },
 250        { 3, { 0x31, 0x04, 0x09 } },
 251        { 2, { 0x05, 0x02 } },
 252        { 6, { 0x06, 0x03, 0x03, 0x08, 0x01, 0x0f } },
 253};
 254
 255static int si4713_start_seq(struct si4713_usb_device *radio)
 256{
 257        int retval = 0;
 258        int i;
 259
 260        radio->buffer[0] = 0x3f;
 261
 262        for (i = 0; i < ARRAY_SIZE(start_seq); i++) {
 263                int len = start_seq[i].len;
 264                const u8 *payload = start_seq[i].payload;
 265
 266                memcpy(radio->buffer + 1, payload, len);
 267                memset(radio->buffer + len + 1, 0, BUFFER_LENGTH - 1 - len);
 268                retval = si4713_send_startup_command(radio);
 269        }
 270
 271        return retval;
 272}
 273
 274static struct i2c_board_info si4713_board_info = {
 275        I2C_BOARD_INFO("si4713", SI4713_I2C_ADDR_BUSEN_HIGH),
 276};
 277
 278struct si4713_command_table {
 279        int command_id;
 280        u8 payload[8];
 281};
 282
 283/*
 284 * Structure of a command :
 285 *      Byte 1 : 0x3f (always)
 286 *      Byte 2 : 0x06 (send a command)
 287 *      Byte 3 : Unknown
 288 *      Byte 4 : Number of arguments + 1 (for the command byte)
 289 *      Byte 5 : Number of response bytes
 290 */
 291static struct si4713_command_table command_table[] = {
 292
 293        { SI4713_CMD_POWER_UP,          { 0x00, SI4713_PWUP_NARGS + 1, SI4713_PWUP_NRESP} },
 294        { SI4713_CMD_GET_REV,           { 0x03, 0x01, SI4713_GETREV_NRESP } },
 295        { SI4713_CMD_POWER_DOWN,        { 0x00, 0x01, SI4713_PWDN_NRESP} },
 296        { SI4713_CMD_SET_PROPERTY,      { 0x00, SI4713_SET_PROP_NARGS + 1, SI4713_SET_PROP_NRESP } },
 297        { SI4713_CMD_GET_PROPERTY,      { 0x00, SI4713_GET_PROP_NARGS + 1, SI4713_GET_PROP_NRESP } },
 298        { SI4713_CMD_TX_TUNE_FREQ,      { 0x03, SI4713_TXFREQ_NARGS + 1, SI4713_TXFREQ_NRESP } },
 299        { SI4713_CMD_TX_TUNE_POWER,     { 0x03, SI4713_TXPWR_NARGS + 1, SI4713_TXPWR_NRESP } },
 300        { SI4713_CMD_TX_TUNE_MEASURE,   { 0x03, SI4713_TXMEA_NARGS + 1, SI4713_TXMEA_NRESP } },
 301        { SI4713_CMD_TX_TUNE_STATUS,    { 0x00, SI4713_TXSTATUS_NARGS + 1, SI4713_TXSTATUS_NRESP } },
 302        { SI4713_CMD_TX_ASQ_STATUS,     { 0x03, SI4713_ASQSTATUS_NARGS + 1, SI4713_ASQSTATUS_NRESP } },
 303        { SI4713_CMD_GET_INT_STATUS,    { 0x03, 0x01, SI4713_GET_STATUS_NRESP } },
 304        { SI4713_CMD_TX_RDS_BUFF,       { 0x03, SI4713_RDSBUFF_NARGS + 1, SI4713_RDSBUFF_NRESP } },
 305        { SI4713_CMD_TX_RDS_PS,         { 0x00, SI4713_RDSPS_NARGS + 1, SI4713_RDSPS_NRESP } },
 306};
 307
 308static int send_command(struct si4713_usb_device *radio, u8 *payload, char *data, int len)
 309{
 310        int retval;
 311
 312        radio->buffer[0] = 0x3f;
 313        radio->buffer[1] = 0x06;
 314
 315        memcpy(radio->buffer + 2, payload, 3);
 316        memcpy(radio->buffer + 5, data, len);
 317        memset(radio->buffer + 5 + len, 0, BUFFER_LENGTH - 5 - len);
 318
 319        /* send the command */
 320        retval = usb_control_msg(radio->usbdev, usb_sndctrlpipe(radio->usbdev, 0),
 321                                        0x09, 0x21, 0x033f, 0, radio->buffer,
 322                                        BUFFER_LENGTH, USB_TIMEOUT);
 323
 324        return retval < 0 ? retval : 0;
 325}
 326
 327static int si4713_i2c_read(struct si4713_usb_device *radio, char *data, int len)
 328{
 329        unsigned long until_jiffies = jiffies + usecs_to_jiffies(USB_RESP_TIMEOUT) + 1;
 330        int retval;
 331
 332        /* receive the response */
 333        for (;;) {
 334                retval = usb_control_msg(radio->usbdev,
 335                                        usb_rcvctrlpipe(radio->usbdev, 0),
 336                                        0x01, 0xa1, 0x033f, 0, radio->buffer,
 337                                        BUFFER_LENGTH, USB_TIMEOUT);
 338                if (retval < 0)
 339                        return retval;
 340
 341                /*
 342                 * Check that we get a valid reply back (buffer[1] == 0) and
 343                 * that CTS is set before returning, otherwise we wait and try
 344                 * again. The i2c driver also does the CTS check, but the timeouts
 345                 * used there are much too small for this USB driver, so we wait
 346                 * for it here.
 347                 */
 348                if (radio->buffer[1] == 0 && (radio->buffer[2] & SI4713_CTS)) {
 349                        memcpy(data, radio->buffer + 2, len);
 350                        return 0;
 351                }
 352                if (time_is_before_jiffies(until_jiffies)) {
 353                        /* Zero the status value, ensuring CTS isn't set */
 354                        data[0] = 0;
 355                        return 0;
 356                }
 357                msleep(3);
 358        }
 359}
 360
 361static int si4713_i2c_write(struct si4713_usb_device *radio, char *data, int len)
 362{
 363        int retval = -EINVAL;
 364        int i;
 365
 366        if (len > BUFFER_LENGTH - 5)
 367                return -EINVAL;
 368
 369        for (i = 0; i < ARRAY_SIZE(command_table); i++) {
 370                if (data[0] == command_table[i].command_id)
 371                        retval = send_command(radio, command_table[i].payload,
 372                                                data, len);
 373        }
 374
 375        return retval < 0 ? retval : 0;
 376}
 377
 378static int si4713_transfer(struct i2c_adapter *i2c_adapter,
 379                                struct i2c_msg *msgs, int num)
 380{
 381        struct si4713_usb_device *radio = i2c_get_adapdata(i2c_adapter);
 382        int retval = -EINVAL;
 383        int i;
 384
 385        if (num <= 0)
 386                return 0;
 387
 388        for (i = 0; i < num; i++) {
 389                if (msgs[i].flags & I2C_M_RD)
 390                        retval = si4713_i2c_read(radio, msgs[i].buf, msgs[i].len);
 391                else
 392                        retval = si4713_i2c_write(radio, msgs[i].buf, msgs[i].len);
 393                if (retval)
 394                        break;
 395        }
 396
 397        return retval ? retval : num;
 398}
 399
 400static u32 si4713_functionality(struct i2c_adapter *adapter)
 401{
 402        return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
 403}
 404
 405static struct i2c_algorithm si4713_algo = {
 406        .master_xfer   = si4713_transfer,
 407        .functionality = si4713_functionality,
 408};
 409
 410/* This name value shows up in the sysfs filename associated
 411                with this I2C adapter */
 412static struct i2c_adapter si4713_i2c_adapter_template = {
 413        .name   = "si4713-i2c",
 414        .owner  = THIS_MODULE,
 415        .algo   = &si4713_algo,
 416};
 417
 418static int si4713_register_i2c_adapter(struct si4713_usb_device *radio)
 419{
 420        radio->i2c_adapter = si4713_i2c_adapter_template;
 421        /* set up sysfs linkage to our parent device */
 422        radio->i2c_adapter.dev.parent = &radio->usbdev->dev;
 423        i2c_set_adapdata(&radio->i2c_adapter, radio);
 424
 425        return i2c_add_adapter(&radio->i2c_adapter);
 426}
 427
 428/* check if the device is present and register with v4l and usb if it is */
 429static int usb_si4713_probe(struct usb_interface *intf,
 430                                const struct usb_device_id *id)
 431{
 432        struct si4713_usb_device *radio;
 433        struct i2c_adapter *adapter;
 434        struct v4l2_subdev *sd;
 435        int retval = -ENOMEM;
 436
 437        dev_info(&intf->dev, "Si4713 development board discovered: (%04X:%04X)\n",
 438                        id->idVendor, id->idProduct);
 439
 440        /* Initialize local device structure */
 441        radio = kzalloc(sizeof(struct si4713_usb_device), GFP_KERNEL);
 442        if (radio)
 443                radio->buffer = kmalloc(BUFFER_LENGTH, GFP_KERNEL);
 444
 445        if (!radio || !radio->buffer) {
 446                dev_err(&intf->dev, "kmalloc for si4713_usb_device failed\n");
 447                kfree(radio);
 448                return -ENOMEM;
 449        }
 450
 451        mutex_init(&radio->lock);
 452
 453        radio->usbdev = interface_to_usbdev(intf);
 454        radio->intf = intf;
 455        usb_set_intfdata(intf, &radio->v4l2_dev);
 456
 457        retval = si4713_start_seq(radio);
 458        if (retval < 0)
 459                goto err_v4l2;
 460
 461        retval = v4l2_device_register(&intf->dev, &radio->v4l2_dev);
 462        if (retval < 0) {
 463                dev_err(&intf->dev, "couldn't register v4l2_device\n");
 464                goto err_v4l2;
 465        }
 466
 467        retval = si4713_register_i2c_adapter(radio);
 468        if (retval < 0) {
 469                dev_err(&intf->dev, "could not register i2c device\n");
 470                goto err_i2cdev;
 471        }
 472
 473        adapter = &radio->i2c_adapter;
 474        sd = v4l2_i2c_new_subdev_board(&radio->v4l2_dev, adapter,
 475                                          &si4713_board_info, NULL);
 476        radio->v4l2_subdev = sd;
 477        if (!sd) {
 478                dev_err(&intf->dev, "cannot get v4l2 subdevice\n");
 479                retval = -ENODEV;
 480                goto del_adapter;
 481        }
 482
 483        radio->vdev.ctrl_handler = sd->ctrl_handler;
 484        radio->v4l2_dev.release = usb_si4713_video_device_release;
 485        strlcpy(radio->vdev.name, radio->v4l2_dev.name,
 486                sizeof(radio->vdev.name));
 487        radio->vdev.v4l2_dev = &radio->v4l2_dev;
 488        radio->vdev.fops = &usb_si4713_fops;
 489        radio->vdev.ioctl_ops = &usb_si4713_ioctl_ops;
 490        radio->vdev.lock = &radio->lock;
 491        radio->vdev.release = video_device_release_empty;
 492        radio->vdev.vfl_dir = VFL_DIR_TX;
 493
 494        video_set_drvdata(&radio->vdev, radio);
 495
 496        retval = video_register_device(&radio->vdev, VFL_TYPE_RADIO, -1);
 497        if (retval < 0) {
 498                dev_err(&intf->dev, "could not register video device\n");
 499                goto del_adapter;
 500        }
 501
 502        dev_info(&intf->dev, "V4L2 device registered as %s\n",
 503                        video_device_node_name(&radio->vdev));
 504
 505        return 0;
 506
 507del_adapter:
 508        i2c_del_adapter(adapter);
 509err_i2cdev:
 510        v4l2_device_unregister(&radio->v4l2_dev);
 511err_v4l2:
 512        kfree(radio->buffer);
 513        kfree(radio);
 514        return retval;
 515}
 516
 517static void usb_si4713_disconnect(struct usb_interface *intf)
 518{
 519        struct si4713_usb_device *radio = to_si4713_dev(usb_get_intfdata(intf));
 520
 521        dev_info(&intf->dev, "Si4713 development board now disconnected\n");
 522
 523        mutex_lock(&radio->lock);
 524        usb_set_intfdata(intf, NULL);
 525        video_unregister_device(&radio->vdev);
 526        v4l2_device_disconnect(&radio->v4l2_dev);
 527        mutex_unlock(&radio->lock);
 528        v4l2_device_put(&radio->v4l2_dev);
 529}
 530
 531/* USB subsystem interface */
 532static struct usb_driver usb_si4713_driver = {
 533        .name                   = "radio-usb-si4713",
 534        .probe                  = usb_si4713_probe,
 535        .disconnect             = usb_si4713_disconnect,
 536        .id_table               = usb_si4713_usb_device_table,
 537};
 538
 539module_usb_driver(usb_si4713_driver);
 540
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