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|
/*
* Copyright 2013 Cisco Systems, Inc. and/or its affiliates.
* All rights reserved.
*
* This program is free software; you may redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
/* kernel includes */
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/usb.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/input.h>
#include <linux/mutex.h>
#include <linux/i2c.h>
/* V4l includes */
#include <linux/videodev2.h>
#include <media/v4l2-common.h>
#include <media/v4l2-device.h>
#include <media/v4l2-ioctl.h>
#include <media/v4l2-event.h>
#include <linux/platform_data/media/si4713.h>
#include "si4713.h"
/* driver and module definitions */
MODULE_AUTHOR("Dinesh Ram <dinesh.ram@cern.ch>");
MODULE_DESCRIPTION("Si4713 FM Transmitter USB driver");
MODULE_LICENSE("GPL v2");
/* The Device announces itself as Cygnal Integrated Products, Inc. */
#define USB_SI4713_VENDOR 0x10c4
#define USB_SI4713_PRODUCT 0x8244
#define BUFFER_LENGTH 64
#define USB_TIMEOUT 1000
#define USB_RESP_TIMEOUT 50000
/* USB Device ID List */
static const struct usb_device_id usb_si4713_usb_device_table[] = {
{USB_DEVICE_AND_INTERFACE_INFO(USB_SI4713_VENDOR, USB_SI4713_PRODUCT,
USB_CLASS_HID, 0, 0) },
{ } /* Terminating entry */
};
MODULE_DEVICE_TABLE(usb, usb_si4713_usb_device_table);
struct si4713_usb_device {
struct usb_device *usbdev;
struct usb_interface *intf;
struct video_device vdev;
struct v4l2_device v4l2_dev;
struct v4l2_subdev *v4l2_subdev;
struct mutex lock;
struct i2c_adapter i2c_adapter;
u8 *buffer;
};
static inline struct si4713_usb_device *to_si4713_dev(struct v4l2_device *v4l2_dev)
{
return container_of(v4l2_dev, struct si4713_usb_device, v4l2_dev);
}
static int vidioc_querycap(struct file *file, void *priv,
struct v4l2_capability *v)
{
struct si4713_usb_device *radio = video_drvdata(file);
strlcpy(v->driver, "radio-usb-si4713", sizeof(v->driver));
strlcpy(v->card, "Si4713 FM Transmitter", sizeof(v->card));
usb_make_path(radio->usbdev, v->bus_info, sizeof(v->bus_info));
v->device_caps = V4L2_CAP_MODULATOR | V4L2_CAP_RDS_OUTPUT;
v->capabilities = v->device_caps | V4L2_CAP_DEVICE_CAPS;
return 0;
}
static int vidioc_g_modulator(struct file *file, void *priv,
struct v4l2_modulator *vm)
{
struct si4713_usb_device *radio = video_drvdata(file);
return v4l2_subdev_call(radio->v4l2_subdev, tuner, g_modulator, vm);
}
static int vidioc_s_modulator(struct file *file, void *priv,
const struct v4l2_modulator *vm)
{
struct si4713_usb_device *radio = video_drvdata(file);
return v4l2_subdev_call(radio->v4l2_subdev, tuner, s_modulator, vm);
}
static int vidioc_s_frequency(struct file *file, void *priv,
const struct v4l2_frequency *vf)
{
struct si4713_usb_device *radio = video_drvdata(file);
return v4l2_subdev_call(radio->v4l2_subdev, tuner, s_frequency, vf);
}
static int vidioc_g_frequency(struct file *file, void *priv,
struct v4l2_frequency *vf)
{
struct si4713_usb_device *radio = video_drvdata(file);
return v4l2_subdev_call(radio->v4l2_subdev, tuner, g_frequency, vf);
}
static const struct v4l2_ioctl_ops usb_si4713_ioctl_ops = {
.vidioc_querycap = vidioc_querycap,
.vidioc_g_modulator = vidioc_g_modulator,
.vidioc_s_modulator = vidioc_s_modulator,
.vidioc_g_frequency = vidioc_g_frequency,
.vidioc_s_frequency = vidioc_s_frequency,
.vidioc_log_status = v4l2_ctrl_log_status,
.vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
.vidioc_unsubscribe_event = v4l2_event_unsubscribe,
};
/* File system interface */
static const struct v4l2_file_operations usb_si4713_fops = {
.owner = THIS_MODULE,
.open = v4l2_fh_open,
.release = v4l2_fh_release,
.poll = v4l2_ctrl_poll,
.unlocked_ioctl = video_ioctl2,
};
static void usb_si4713_video_device_release(struct v4l2_device *v4l2_dev)
{
struct si4713_usb_device *radio = to_si4713_dev(v4l2_dev);
struct i2c_adapter *adapter = &radio->i2c_adapter;
i2c_del_adapter(adapter);
v4l2_device_unregister(&radio->v4l2_dev);
kfree(radio->buffer);
kfree(radio);
}
/*
* This command sequence emulates the behaviour of the Windows driver.
* The structure of these commands was determined by sniffing the
* usb traffic of the device during startup.
* Most likely, these commands make some queries to the device.
* Commands are sent to enquire parameters like the bus mode,
* component revision, boot mode, the device serial number etc.
*
* These commands are necessary to be sent in this order during startup.
* The device fails to powerup if these commands are not sent.
*
* The complete list of startup commands is given in the start_seq table below.
*/
static int si4713_send_startup_command(struct si4713_usb_device *radio)
{
unsigned long until_jiffies = jiffies + usecs_to_jiffies(USB_RESP_TIMEOUT) + 1;
u8 *buffer = radio->buffer;
int retval;
/* send the command */
retval = usb_control_msg(radio->usbdev, usb_sndctrlpipe(radio->usbdev, 0),
0x09, 0x21, 0x033f, 0, radio->buffer,
BUFFER_LENGTH, USB_TIMEOUT);
if (retval < 0)
return retval;
for (;;) {
/* receive the response */
retval = usb_control_msg(radio->usbdev, usb_rcvctrlpipe(radio->usbdev, 0),
0x01, 0xa1, 0x033f, 0, radio->buffer,
BUFFER_LENGTH, USB_TIMEOUT);
if (retval < 0)
return retval;
if (!radio->buffer[1]) {
/* USB traffic sniffing showed that some commands require
* additional checks. */
switch (buffer[1]) {
case 0x32:
if (radio->buffer[2] == 0)
return 0;
break;
case 0x14:
case 0x12:
if (radio->buffer[2] & SI4713_CTS)
return 0;
break;
case 0x06:
if ((radio->buffer[2] & SI4713_CTS) && radio->buffer[9] == 0x08)
return 0;
break;
default:
return 0;
}
}
if (time_is_before_jiffies(until_jiffies))
return -EIO;
msleep(3);
}
return retval;
}
struct si4713_start_seq_table {
int len;
u8 payload[8];
};
/*
* Some of the startup commands that could be recognized are :
* (0x03): Get serial number of the board (Response : CB000-00-00)
* (0x06, 0x03, 0x03, 0x08, 0x01, 0x0f) : Get Component revision
*/
static const struct si4713_start_seq_table start_seq[] = {
{ 1, { 0x03 } },
{ 2, { 0x32, 0x7f } },
{ 6, { 0x06, 0x03, 0x03, 0x08, 0x01, 0x0f } },
{ 2, { 0x14, 0x02 } },
{ 2, { 0x09, 0x90 } },
{ 3, { 0x08, 0x90, 0xfa } },
{ 2, { 0x36, 0x01 } },
{ 2, { 0x05, 0x03 } },
{ 7, { 0x06, 0x00, 0x06, 0x0e, 0x01, 0x0f, 0x05 } },
{ 1, { 0x12 } },
/* Commands that are sent after pressing the 'Initialize'
button in the windows application */
{ 1, { 0x03 } },
{ 1, { 0x01 } },
{ 2, { 0x09, 0x90 } },
{ 3, { 0x08, 0x90, 0xfa } },
{ 1, { 0x34 } },
{ 2, { 0x35, 0x01 } },
{ 2, { 0x36, 0x01 } },
{ 2, { 0x30, 0x09 } },
{ 4, { 0x30, 0x06, 0x00, 0xe2 } },
{ 3, { 0x31, 0x01, 0x30 } },
{ 3, { 0x31, 0x04, 0x09 } },
{ 2, { 0x05, 0x02 } },
{ 6, { 0x06, 0x03, 0x03, 0x08, 0x01, 0x0f } },
};
static int si4713_start_seq(struct si4713_usb_device *radio)
{
int retval = 0;
int i;
radio->buffer[0] = 0x3f;
for (i = 0; i < ARRAY_SIZE(start_seq); i++) {
int len = start_seq[i].len;
const u8 *payload = start_seq[i].payload;
memcpy(radio->buffer + 1, payload, len);
memset(radio->buffer + len + 1, 0, BUFFER_LENGTH - 1 - len);
retval = si4713_send_startup_command(radio);
}
return retval;
}
static struct i2c_board_info si4713_board_info = {
I2C_BOARD_INFO("si4713", SI4713_I2C_ADDR_BUSEN_HIGH),
};
struct si4713_command_table {
int command_id;
u8 payload[8];
};
/*
* Structure of a command :
* Byte 1 : 0x3f (always)
* Byte 2 : 0x06 (send a command)
* Byte 3 : Unknown
* Byte 4 : Number of arguments + 1 (for the command byte)
* Byte 5 : Number of response bytes
*/
static struct si4713_command_table command_table[] = {
{ SI4713_CMD_POWER_UP, { 0x00, SI4713_PWUP_NARGS + 1, SI4713_PWUP_NRESP} },
{ SI4713_CMD_GET_REV, { 0x03, 0x01, SI4713_GETREV_NRESP } },
{ SI4713_CMD_POWER_DOWN, { 0x00, 0x01, SI4713_PWDN_NRESP} },
{ SI4713_CMD_SET_PROPERTY, { 0x00, SI4713_SET_PROP_NARGS + 1, SI4713_SET_PROP_NRESP } },
{ SI4713_CMD_GET_PROPERTY, { 0x00, SI4713_GET_PROP_NARGS + 1, SI4713_GET_PROP_NRESP } },
{ SI4713_CMD_TX_TUNE_FREQ, { 0x03, SI4713_TXFREQ_NARGS + 1, SI4713_TXFREQ_NRESP } },
{ SI4713_CMD_TX_TUNE_POWER, { 0x03, SI4713_TXPWR_NARGS + 1, SI4713_TXPWR_NRESP } },
{ SI4713_CMD_TX_TUNE_MEASURE, { 0x03, SI4713_TXMEA_NARGS + 1, SI4713_TXMEA_NRESP } },
{ SI4713_CMD_TX_TUNE_STATUS, { 0x00, SI4713_TXSTATUS_NARGS + 1, SI4713_TXSTATUS_NRESP } },
{ SI4713_CMD_TX_ASQ_STATUS, { 0x03, SI4713_ASQSTATUS_NARGS + 1, SI4713_ASQSTATUS_NRESP } },
{ SI4713_CMD_GET_INT_STATUS, { 0x03, 0x01, SI4713_GET_STATUS_NRESP } },
{ SI4713_CMD_TX_RDS_BUFF, { 0x03, SI4713_RDSBUFF_NARGS + 1, SI4713_RDSBUFF_NRESP } },
{ SI4713_CMD_TX_RDS_PS, { 0x00, SI4713_RDSPS_NARGS + 1, SI4713_RDSPS_NRESP } },
};
static int send_command(struct si4713_usb_device *radio, u8 *payload, char *data, int len)
{
int retval;
radio->buffer[0] = 0x3f;
radio->buffer[1] = 0x06;
memcpy(radio->buffer + 2, payload, 3);
memcpy(radio->buffer + 5, data, len);
memset(radio->buffer + 5 + len, 0, BUFFER_LENGTH - 5 - len);
/* send the command */
retval = usb_control_msg(radio->usbdev, usb_sndctrlpipe(radio->usbdev, 0),
0x09, 0x21, 0x033f, 0, radio->buffer,
BUFFER_LENGTH, USB_TIMEOUT);
return retval < 0 ? retval : 0;
}
static int si4713_i2c_read(struct si4713_usb_device *radio, char *data, int len)
{
unsigned long until_jiffies = jiffies + usecs_to_jiffies(USB_RESP_TIMEOUT) + 1;
int retval;
/* receive the response */
for (;;) {
retval = usb_control_msg(radio->usbdev,
usb_rcvctrlpipe(radio->usbdev, 0),
0x01, 0xa1, 0x033f, 0, radio->buffer,
BUFFER_LENGTH, USB_TIMEOUT);
if (retval < 0)
return retval;
/*
* Check that we get a valid reply back (buffer[1] == 0) and
* that CTS is set before returning, otherwise we wait and try
* again. The i2c driver also does the CTS check, but the timeouts
* used there are much too small for this USB driver, so we wait
* for it here.
*/
if (radio->buffer[1] == 0 && (radio->buffer[2] & SI4713_CTS)) {
memcpy(data, radio->buffer + 2, len);
return 0;
}
if (time_is_before_jiffies(until_jiffies)) {
/* Zero the status value, ensuring CTS isn't set */
data[0] = 0;
return 0;
}
msleep(3);
}
}
static int si4713_i2c_write(struct si4713_usb_device *radio, char *data, int len)
{
int retval = -EINVAL;
int i;
if (len > BUFFER_LENGTH - 5)
return -EINVAL;
for (i = 0; i < ARRAY_SIZE(command_table); i++) {
if (data[0] == command_table[i].command_id)
retval = send_command(radio, command_table[i].payload,
data, len);
}
return retval < 0 ? retval : 0;
}
static int si4713_transfer(struct i2c_adapter *i2c_adapter,
struct i2c_msg *msgs, int num)
{
struct si4713_usb_device *radio = i2c_get_adapdata(i2c_adapter);
int retval = -EINVAL;
int i;
if (num <= 0)
return 0;
for (i = 0; i < num; i++) {
if (msgs[i].flags & I2C_M_RD)
retval = si4713_i2c_read(radio, msgs[i].buf, msgs[i].len);
else
retval = si4713_i2c_write(radio, msgs[i].buf, msgs[i].len);
if (retval)
break;
}
return retval ? retval : num;
}
static u32 si4713_functionality(struct i2c_adapter *adapter)
{
return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
}
static const struct i2c_algorithm si4713_algo = {
.master_xfer = si4713_transfer,
.functionality = si4713_functionality,
};
/* This name value shows up in the sysfs filename associated
with this I2C adapter */
static struct i2c_adapter si4713_i2c_adapter_template = {
.name = "si4713-i2c",
.owner = THIS_MODULE,
.algo = &si4713_algo,
};
static int si4713_register_i2c_adapter(struct si4713_usb_device *radio)
{
radio->i2c_adapter = si4713_i2c_adapter_template;
/* set up sysfs linkage to our parent device */
radio->i2c_adapter.dev.parent = &radio->usbdev->dev;
i2c_set_adapdata(&radio->i2c_adapter, radio);
return i2c_add_adapter(&radio->i2c_adapter);
}
/* check if the device is present and register with v4l and usb if it is */
static int usb_si4713_probe(struct usb_interface *intf,
const struct usb_device_id *id)
{
struct si4713_usb_device *radio;
struct i2c_adapter *adapter;
struct v4l2_subdev *sd;
int retval = -ENOMEM;
dev_info(&intf->dev, "Si4713 development board discovered: (%04X:%04X)\n",
id->idVendor, id->idProduct);
/* Initialize local device structure */
radio = kzalloc(sizeof(struct si4713_usb_device), GFP_KERNEL);
if (radio)
radio->buffer = kmalloc(BUFFER_LENGTH, GFP_KERNEL);
if (!radio || !radio->buffer) {
dev_err(&intf->dev, "kmalloc for si4713_usb_device failed\n");
kfree(radio);
return -ENOMEM;
}
mutex_init(&radio->lock);
radio->usbdev = interface_to_usbdev(intf);
radio->intf = intf;
usb_set_intfdata(intf, &radio->v4l2_dev);
retval = si4713_start_seq(radio);
if (retval < 0)
goto err_v4l2;
retval = v4l2_device_register(&intf->dev, &radio->v4l2_dev);
if (retval < 0) {
dev_err(&intf->dev, "couldn't register v4l2_device\n");
goto err_v4l2;
}
retval = si4713_register_i2c_adapter(radio);
if (retval < 0) {
dev_err(&intf->dev, "could not register i2c device\n");
goto err_i2cdev;
}
adapter = &radio->i2c_adapter;
sd = v4l2_i2c_new_subdev_board(&radio->v4l2_dev, adapter,
&si4713_board_info, NULL);
radio->v4l2_subdev = sd;
if (!sd) {
dev_err(&intf->dev, "cannot get v4l2 subdevice\n");
retval = -ENODEV;
goto del_adapter;
}
radio->vdev.ctrl_handler = sd->ctrl_handler;
radio->v4l2_dev.release = usb_si4713_video_device_release;
strlcpy(radio->vdev.name, radio->v4l2_dev.name,
sizeof(radio->vdev.name));
radio->vdev.v4l2_dev = &radio->v4l2_dev;
radio->vdev.fops = &usb_si4713_fops;
radio->vdev.ioctl_ops = &usb_si4713_ioctl_ops;
radio->vdev.lock = &radio->lock;
radio->vdev.release = video_device_release_empty;
radio->vdev.vfl_dir = VFL_DIR_TX;
video_set_drvdata(&radio->vdev, radio);
retval = video_register_device(&radio->vdev, VFL_TYPE_RADIO, -1);
if (retval < 0) {
dev_err(&intf->dev, "could not register video device\n");
goto del_adapter;
}
dev_info(&intf->dev, "V4L2 device registered as %s\n",
video_device_node_name(&radio->vdev));
return 0;
del_adapter:
i2c_del_adapter(adapter);
err_i2cdev:
v4l2_device_unregister(&radio->v4l2_dev);
err_v4l2:
kfree(radio->buffer);
kfree(radio);
return retval;
}
static void usb_si4713_disconnect(struct usb_interface *intf)
{
struct si4713_usb_device *radio = to_si4713_dev(usb_get_intfdata(intf));
dev_info(&intf->dev, "Si4713 development board now disconnected\n");
mutex_lock(&radio->lock);
usb_set_intfdata(intf, NULL);
video_unregister_device(&radio->vdev);
v4l2_device_disconnect(&radio->v4l2_dev);
mutex_unlock(&radio->lock);
v4l2_device_put(&radio->v4l2_dev);
}
/* USB subsystem interface */
static struct usb_driver usb_si4713_driver = {
.name = "radio-usb-si4713",
.probe = usb_si4713_probe,
.disconnect = usb_si4713_disconnect,
.id_table = usb_si4713_usb_device_table,
};
module_usb_driver(usb_si4713_driver);
|