linux/drivers/media/rc/streamzap.c
Sean Young 8b3179b721 media: streamzap: remove redundant gap calculations
The lirc core already introduces gaps, so there is no need for this in
the driver.

Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2021-12-14 15:09:13 +01:00

422 lines
10 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Streamzap Remote Control driver
*
* Copyright (c) 2005 Christoph Bartelmus <lirc@bartelmus.de>
* Copyright (c) 2010 Jarod Wilson <jarod@wilsonet.com>
*
* 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 (greg@kroah.com)
*/
#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_NAME "streamzap"
#define DRIVER_DESC "Streamzap Remote Control driver"
#define USB_STREAMZAP_VENDOR_ID 0x0e9c
#define USB_STREAMZAP_PRODUCT_ID 0x0000
/* table of devices that work with this driver */
static const 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
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 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;
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)
{
struct ir_raw_event rawir = {
.pulse = true,
.duration = value * SZ_RESOLUTION + SZ_RESOLUTION / 2,
};
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)
{
struct ir_raw_event rawir = {
.pulse = false,
.duration = value * SZ_RESOLUTION + SZ_RESOLUTION / 2,
};
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);
}
/*
* streamzap_callback - usb IRQ handler callback
*
* This procedure is invoked on reception of data from
* the usb remote.
*/
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) {
struct ir_raw_event rawir = {
.pulse = false,
.duration = sz->rdev->timeout
};
sz_push(sz, rawir);
} 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);
}
static struct rc_dev *streamzap_init_rc_dev(struct streamzap_ir *sz,
struct usb_device *usbdev)
{
struct rc_dev *rdev;
struct device *dev = sz->dev;
int ret;
rdev = rc_allocate_device(RC_DRIVER_IR_RAW);
if (!rdev)
goto out;
usb_make_path(usbdev, sz->phys, sizeof(sz->phys));
strlcat(sz->phys, "/input0", sizeof(sz->phys));
rdev->device_name = "Streamzap PC Remote Infrared Receiver";
rdev->input_phys = sz->phys;
usb_to_input_id(usbdev, &rdev->input_id);
rdev->dev.parent = dev;
rdev->priv = sz;
rdev->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER;
rdev->driver_name = DRIVER_NAME;
rdev->map_name = RC_MAP_STREAMZAP;
rdev->rx_resolution = SZ_RESOLUTION;
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;
}
/*
* streamzap_probe
*
* Called by usb-core to associated with a candidate device
* On any failure the return value is the ERROR
* On success return 0
*/
static int streamzap_probe(struct usb_interface *intf,
const struct usb_device_id *id)
{
struct usb_device *usbdev = interface_to_usbdev(intf);
struct usb_endpoint_descriptor *endpoint;
struct usb_host_interface *iface_host;
struct streamzap_ir *sz = NULL;
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;
/* 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;
}
endpoint = &iface_host->endpoint[0].desc;
if (!usb_endpoint_dir_in(endpoint)) {
dev_err(&intf->dev, "%s: endpoint doesn't match input device 02%02x\n",
__func__, endpoint->bEndpointAddress);
retval = -ENODEV;
goto free_sz;
}
if (!usb_endpoint_xfer_int(endpoint)) {
dev_err(&intf->dev, "%s: endpoint attributes don't match xfer 02%02x\n",
__func__, endpoint->bmAttributes);
retval = -ENODEV;
goto free_sz;
}
pipe = usb_rcvintpipe(usbdev, 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;
sz->rdev = streamzap_init_rc_dev(sz, usbdev);
if (!sz->rdev)
goto rc_dev_fail;
sz->decoder_state = PulseSpace;
/* FIXME: don't yet have a way to set this */
sz->rdev->timeout = SZ_TIMEOUT * SZ_RESOLUTION;
#if 0
/* not yet supported, depends on patches from maxim */
/* see also: LIRC_GET_REC_RESOLUTION and LIRC_SET_REC_TIMEOUT */
sz->min_timeout = SZ_TIMEOUT * SZ_RESOLUTION;
sz->max_timeout = SZ_TIMEOUT * SZ_RESOLUTION;
#endif
/* Complete final initialisations */
usb_fill_int_urb(sz->urb_in, usbdev, pipe, sz->buf_in,
maxp, streamzap_callback, 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");
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;
}
/*
* streamzap_disconnect
*
* Called by the usb core when the device is removed from the system.
*
* This routine guarantees that the driver will not submit any more urbs
* by clearing dev->usbdev. It is also supposed to terminate any currently
* active urbs. Unfortunately, usb_bulk_msg(), used in streamzap_read(),
* does not provide any way to do this.
*/
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;
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 submitting urb\n");
return -EIO;
}
return 0;
}
module_usb_driver(streamzap_driver);
MODULE_AUTHOR("Jarod Wilson <jarod@wilsonet.com>");
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");