streamzap.c

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/*
 * Streamzap Remote Control driver
 *
 * Copyright (c) 2005 Christoph Bartelmus <[email protected]>
 * Copyright (c) 2010 Jarod Wilson <[email protected]>
 *
 * This driver was based on the work of Greg Wickham and Adrian
 * Dewhurst. It was substantially rewritten to support correct signal
 * gaps and now maintains a delay buffer, which is used to present
 * consistent timing behaviour to user space applications. Without the
 * delay buffer an ugly hack would be required in lircd, which can
 * cause sluggish signal decoding in certain situations.
 *
 * Ported to in-kernel ir-core interface by Jarod Wilson
 *
 * This driver is based on the USB skeleton driver packaged with the
 * kernel; copyright (C) 2001-2003 Greg Kroah-Hartman ([email protected])
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include <linux/device.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/usb.h>
#include <linux/usb/input.h>
#include <media/rc-core.h>

#define DRIVER_VERSION  "1.61"
#define DRIVER_NAME "streamzap"
#define DRIVER_DESC "Streamzap Remote Control driver"

#ifdef CONFIG_USB_DEBUG
static bool debug = 1;
#else
static bool debug;
#endif

#define USB_STREAMZAP_VENDOR_ID     0x0e9c
#define USB_STREAMZAP_PRODUCT_ID    0x0000

/* table of devices that work with this driver */
static struct usb_device_id streamzap_table[] = {
    /* Streamzap Remote Control */
    { USB_DEVICE(USB_STREAMZAP_VENDOR_ID, USB_STREAMZAP_PRODUCT_ID) },
    /* Terminating entry */
    { }
};

MODULE_DEVICE_TABLE(usb, streamzap_table);

#define SZ_PULSE_MASK 0xf0
#define SZ_SPACE_MASK 0x0f
#define SZ_TIMEOUT    0xff
#define SZ_RESOLUTION 256

/* number of samples buffered */
#define SZ_BUF_LEN 128

/* from ir-rc5-sz-decoder.c */
#ifdef CONFIG_IR_RC5_SZ_DECODER_MODULE
#define load_rc5_sz_decode()    request_module("ir-rc5-sz-decoder")
#else
#define load_rc5_sz_decode()    {}
#endif

enum StreamzapDecoderState {
    PulseSpace,
    FullPulse,
    FullSpace,
    IgnorePulse
};

/* structure to hold our device specific stuff */
struct streamzap_ir {
    /* ir-core */
    struct rc_dev *rdev;

    /* core device info */
    struct device *dev;

    /* usb */
    struct usb_device   *usbdev;
    struct usb_interface    *interface;
    struct usb_endpoint_descriptor *endpoint;
    struct urb      *urb_in;

    /* buffer & dma */
    unsigned char       *buf_in;
    dma_addr_t      dma_in;
    unsigned int        buf_in_len;

    /* track what state we're in */
    enum StreamzapDecoderState decoder_state;
    /* tracks whether we are currently receiving some signal */
    bool            idle;
    /* sum of signal lengths received since signal start */
    unsigned long       sum;
    /* start time of signal; necessary for gap tracking */
    struct timeval      signal_last;
    struct timeval      signal_start;
    bool            timeout_enabled;

    char            name[128];
    char            phys[64];
};


/* local function prototypes */
static int streamzap_probe(struct usb_interface *interface,
               const struct usb_device_id *id);
static void streamzap_disconnect(struct usb_interface *interface);
static void streamzap_callback(struct urb *urb);
static int streamzap_suspend(struct usb_interface *intf, pm_message_t message);
static int streamzap_resume(struct usb_interface *intf);

/* usb specific object needed to register this driver with the usb subsystem */
static struct usb_driver streamzap_driver = {
    .name =     DRIVER_NAME,
    .probe =    streamzap_probe,
    .disconnect =   streamzap_disconnect,
    .suspend =  streamzap_suspend,
    .resume =   streamzap_resume,
    .id_table = streamzap_table,
};

static void sz_push(struct streamzap_ir *sz, struct ir_raw_event rawir)
{
    dev_dbg(sz->dev, "Storing %s with duration %u us\n",
        (rawir.pulse ? "pulse" : "space"), rawir.duration);
    ir_raw_event_store_with_filter(sz->rdev, &rawir);
}

static void sz_push_full_pulse(struct streamzap_ir *sz,
                   unsigned char value)
{
    DEFINE_IR_RAW_EVENT(rawir);

    if (sz->idle) {
        long deltv;

        sz->signal_last = sz->signal_start;
        do_gettimeofday(&sz->signal_start);

        deltv = sz->signal_start.tv_sec - sz->signal_last.tv_sec;
        rawir.pulse = false;
        if (deltv > 15) {
            /* really long time */
            rawir.duration = IR_MAX_DURATION;
        } else {
            rawir.duration = (int)(deltv * 1000000 +
                sz->signal_start.tv_usec -
                sz->signal_last.tv_usec);
            rawir.duration -= sz->sum;
            rawir.duration = US_TO_NS(rawir.duration);
            rawir.duration &= IR_MAX_DURATION;
        }
        sz_push(sz, rawir);

        sz->idle = false;
        sz->sum = 0;
    }

    rawir.pulse = true;
    rawir.duration = ((int) value) * SZ_RESOLUTION;
    rawir.duration += SZ_RESOLUTION / 2;
    sz->sum += rawir.duration;
    rawir.duration = US_TO_NS(rawir.duration);
    rawir.duration &= IR_MAX_DURATION;
    sz_push(sz, rawir);
}

static void sz_push_half_pulse(struct streamzap_ir *sz,
                   unsigned char value)
{
    sz_push_full_pulse(sz, (value & SZ_PULSE_MASK) >> 4);
}

static void sz_push_full_space(struct streamzap_ir *sz,
                   unsigned char value)
{
    DEFINE_IR_RAW_EVENT(rawir);

    rawir.pulse = false;
    rawir.duration = ((int) value) * SZ_RESOLUTION;
    rawir.duration += SZ_RESOLUTION / 2;
    sz->sum += rawir.duration;
    rawir.duration = US_TO_NS(rawir.duration);
    sz_push(sz, rawir);
}

static void sz_push_half_space(struct streamzap_ir *sz,
                   unsigned long value)
{
    sz_push_full_space(sz, value & SZ_SPACE_MASK);
}

static void streamzap_callback(struct urb *urb)
{
    struct streamzap_ir *sz;
    unsigned int i;
    int len;

    if (!urb)
        return;

    sz = urb->context;
    len = urb->actual_length;

    switch (urb->status) {
    case -ECONNRESET:
    case -ENOENT:
    case -ESHUTDOWN:
        /*
         * this urb is terminated, clean up.
         * sz might already be invalid at this point
         */
        dev_err(sz->dev, "urb terminated, status: %d\n", urb->status);
        return;
    default:
        break;
    }

    dev_dbg(sz->dev, "%s: received urb, len %d\n", __func__, len);
    for (i = 0; i < len; i++) {
        dev_dbg(sz->dev, "sz->buf_in[%d]: %x\n",
            i, (unsigned char)sz->buf_in[i]);
        switch (sz->decoder_state) {
        case PulseSpace:
            if ((sz->buf_in[i] & SZ_PULSE_MASK) ==
                SZ_PULSE_MASK) {
                sz->decoder_state = FullPulse;
                continue;
            } else if ((sz->buf_in[i] & SZ_SPACE_MASK)
                    == SZ_SPACE_MASK) {
                sz_push_half_pulse(sz, sz->buf_in[i]);
                sz->decoder_state = FullSpace;
                continue;
            } else {
                sz_push_half_pulse(sz, sz->buf_in[i]);
                sz_push_half_space(sz, sz->buf_in[i]);
            }
            break;
        case FullPulse:
            sz_push_full_pulse(sz, sz->buf_in[i]);
            sz->decoder_state = IgnorePulse;
            break;
        case FullSpace:
            if (sz->buf_in[i] == SZ_TIMEOUT) {
                DEFINE_IR_RAW_EVENT(rawir);

                rawir.pulse = false;
                rawir.duration = sz->rdev->timeout;
                sz->idle = true;
                if (sz->timeout_enabled)
                    sz_push(sz, rawir);
                ir_raw_event_handle(sz->rdev);
                ir_raw_event_reset(sz->rdev);
            } else {
                sz_push_full_space(sz, sz->buf_in[i]);
            }
            sz->decoder_state = PulseSpace;
            break;
        case IgnorePulse:
            if ((sz->buf_in[i] & SZ_SPACE_MASK) ==
                SZ_SPACE_MASK) {
                sz->decoder_state = FullSpace;
                continue;
            }
            sz_push_half_space(sz, sz->buf_in[i]);
            sz->decoder_state = PulseSpace;
            break;
        }
    }

    ir_raw_event_handle(sz->rdev);
    usb_submit_urb(urb, GFP_ATOMIC);

    return;
}

static struct rc_dev *streamzap_init_rc_dev(struct streamzap_ir *sz)
{
    struct rc_dev *rdev;
    struct device *dev = sz->dev;
    int ret;

    rdev = rc_allocate_device();
    if (!rdev) {
        dev_err(dev, "remote dev allocation failed\n");
        goto out;
    }

    snprintf(sz->name, sizeof(sz->name), "Streamzap PC Remote Infrared "
         "Receiver (%04x:%04x)",
         le16_to_cpu(sz->usbdev->descriptor.idVendor),
         le16_to_cpu(sz->usbdev->descriptor.idProduct));
    usb_make_path(sz->usbdev, sz->phys, sizeof(sz->phys));
    strlcat(sz->phys, "/input0", sizeof(sz->phys));

    rdev->input_name = sz->name;
    rdev->input_phys = sz->phys;
    usb_to_input_id(sz->usbdev, &rdev->input_id);
    rdev->dev.parent = dev;
    rdev->priv = sz;
    rdev->driver_type = RC_DRIVER_IR_RAW;
    rdev->allowed_protos = RC_TYPE_ALL;
    rdev->driver_name = DRIVER_NAME;
    rdev->map_name = RC_MAP_STREAMZAP;

    ret = rc_register_device(rdev);
    if (ret < 0) {
        dev_err(dev, "remote input device register failed\n");
        goto out;
    }

    return rdev;

out:
    rc_free_device(rdev);
    return NULL;
}

static int __devinit streamzap_probe(struct usb_interface *intf,
                     const struct usb_device_id *id)
{
    struct usb_device *usbdev = interface_to_usbdev(intf);
    struct usb_host_interface *iface_host;
    struct streamzap_ir *sz = NULL;
    char buf[63], name[128] = "";
    int retval = -ENOMEM;
    int pipe, maxp;

    /* Allocate space for device driver specific data */
    sz = kzalloc(sizeof(struct streamzap_ir), GFP_KERNEL);
    if (!sz)
        return -ENOMEM;

    sz->usbdev = usbdev;
    sz->interface = intf;

    /* Check to ensure endpoint information matches requirements */
    iface_host = intf->cur_altsetting;

    if (iface_host->desc.bNumEndpoints != 1) {
        dev_err(&intf->dev, "%s: Unexpected desc.bNumEndpoints (%d)\n",
            __func__, iface_host->desc.bNumEndpoints);
        retval = -ENODEV;
        goto free_sz;
    }

    sz->endpoint = &(iface_host->endpoint[0].desc);
    if ((sz->endpoint->bEndpointAddress & USB_ENDPOINT_DIR_MASK)
        != USB_DIR_IN) {
        dev_err(&intf->dev, "%s: endpoint doesn't match input device "
            "02%02x\n", __func__, sz->endpoint->bEndpointAddress);
        retval = -ENODEV;
        goto free_sz;
    }

    if ((sz->endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
        != USB_ENDPOINT_XFER_INT) {
        dev_err(&intf->dev, "%s: endpoint attributes don't match xfer "
            "02%02x\n", __func__, sz->endpoint->bmAttributes);
        retval = -ENODEV;
        goto free_sz;
    }

    pipe = usb_rcvintpipe(usbdev, sz->endpoint->bEndpointAddress);
    maxp = usb_maxpacket(usbdev, pipe, usb_pipeout(pipe));

    if (maxp == 0) {
        dev_err(&intf->dev, "%s: endpoint Max Packet Size is 0!?!\n",
            __func__);
        retval = -ENODEV;
        goto free_sz;
    }

    /* Allocate the USB buffer and IRQ URB */
    sz->buf_in = usb_alloc_coherent(usbdev, maxp, GFP_ATOMIC, &sz->dma_in);
    if (!sz->buf_in)
        goto free_sz;

    sz->urb_in = usb_alloc_urb(0, GFP_KERNEL);
    if (!sz->urb_in)
        goto free_buf_in;

    sz->dev = &intf->dev;
    sz->buf_in_len = maxp;

    if (usbdev->descriptor.iManufacturer
        && usb_string(usbdev, usbdev->descriptor.iManufacturer,
              buf, sizeof(buf)) > 0)
        strlcpy(name, buf, sizeof(name));

    if (usbdev->descriptor.iProduct
        && usb_string(usbdev, usbdev->descriptor.iProduct,
              buf, sizeof(buf)) > 0)
        snprintf(name + strlen(name), sizeof(name) - strlen(name),
             " %s", buf);

    sz->rdev = streamzap_init_rc_dev(sz);
    if (!sz->rdev)
        goto rc_dev_fail;

    sz->idle = true;
    sz->decoder_state = PulseSpace;
    /* FIXME: don't yet have a way to set this */
    sz->timeout_enabled = true;
    sz->rdev->timeout = ((US_TO_NS(SZ_TIMEOUT * SZ_RESOLUTION) &
                IR_MAX_DURATION) | 0x03000000);
    #if 0
    /* not yet supported, depends on patches from maxim */
    /* see also: LIRC_GET_REC_RESOLUTION and LIRC_SET_REC_TIMEOUT */
    sz->min_timeout = US_TO_NS(SZ_TIMEOUT * SZ_RESOLUTION);
    sz->max_timeout = US_TO_NS(SZ_TIMEOUT * SZ_RESOLUTION);
    #endif

    do_gettimeofday(&sz->signal_start);

    /* Complete final initialisations */
    usb_fill_int_urb(sz->urb_in, usbdev, pipe, sz->buf_in,
             maxp, (usb_complete_t)streamzap_callback,
             sz, sz->endpoint->bInterval);
    sz->urb_in->transfer_dma = sz->dma_in;
    sz->urb_in->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;

    usb_set_intfdata(intf, sz);

    if (usb_submit_urb(sz->urb_in, GFP_ATOMIC))
        dev_err(sz->dev, "urb submit failed\n");

    dev_info(sz->dev, "Registered %s on usb%d:%d\n", name,
         usbdev->bus->busnum, usbdev->devnum);

    /* Load the streamzap not-quite-rc5 decoder too */
    load_rc5_sz_decode();

    return 0;

rc_dev_fail:
    usb_free_urb(sz->urb_in);
free_buf_in:
    usb_free_coherent(usbdev, maxp, sz->buf_in, sz->dma_in);
free_sz:
    kfree(sz);

    return retval;
}

static void streamzap_disconnect(struct usb_interface *interface)
{
    struct streamzap_ir *sz = usb_get_intfdata(interface);
    struct usb_device *usbdev = interface_to_usbdev(interface);

    usb_set_intfdata(interface, NULL);

    if (!sz)
        return;

    sz->usbdev = NULL;
    rc_unregister_device(sz->rdev);
    usb_kill_urb(sz->urb_in);
    usb_free_urb(sz->urb_in);
    usb_free_coherent(usbdev, sz->buf_in_len, sz->buf_in, sz->dma_in);

    kfree(sz);
}

static int streamzap_suspend(struct usb_interface *intf, pm_message_t message)
{
    struct streamzap_ir *sz = usb_get_intfdata(intf);

    usb_kill_urb(sz->urb_in);

    return 0;
}

static int streamzap_resume(struct usb_interface *intf)
{
    struct streamzap_ir *sz = usb_get_intfdata(intf);

    if (usb_submit_urb(sz->urb_in, GFP_ATOMIC)) {
        dev_err(sz->dev, "Error sumbiting urb\n");
        return -EIO;
    }

    return 0;
}

module_usb_driver(streamzap_driver);

MODULE_AUTHOR("Jarod Wilson <[email protected]>");
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");

module_param(debug, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug, "Enable debugging messages");