android_kernel_xiaomi_sm8350/drivers/media/video/uvc/uvc_status.c
Ming Lei a31a405547 V4L/DVB:usbvideo:don't use part of buffer for USB transfer #4
The status[] is part of  uvc_device structure. We can't make sure
the address of status is at a cache-line boundary in all archs,so
status[] might share a cache-line with some fields in uvc_structure.
This can lead to some cache coherence issues(http://lwn.net/Articles/2265/).
Use dynamically allocated buffer instead.

Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Acked-by: Laurent Pinchart <laurent.pinchart@skynet.be>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2008-10-12 09:37:08 -02:00

229 lines
5.3 KiB
C

/*
* uvc_status.c -- USB Video Class driver - Status endpoint
*
* Copyright (C) 2007-2008
* Laurent Pinchart (laurent.pinchart@skynet.be)
*
* 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.
*
*/
#include <linux/kernel.h>
#include <linux/version.h>
#include <linux/input.h>
#include <linux/usb.h>
#include <linux/usb/input.h>
#include "uvcvideo.h"
/* --------------------------------------------------------------------------
* Input device
*/
#ifdef CONFIG_USB_VIDEO_CLASS_INPUT_EVDEV
static int uvc_input_init(struct uvc_device *dev)
{
struct usb_device *udev = dev->udev;
struct input_dev *input;
char *phys = NULL;
int ret;
input = input_allocate_device();
if (input == NULL)
return -ENOMEM;
phys = kmalloc(6 + strlen(udev->bus->bus_name) + strlen(udev->devpath),
GFP_KERNEL);
if (phys == NULL) {
ret = -ENOMEM;
goto error;
}
sprintf(phys, "usb-%s-%s", udev->bus->bus_name, udev->devpath);
input->name = dev->name;
input->phys = phys;
usb_to_input_id(udev, &input->id);
input->dev.parent = &dev->intf->dev;
set_bit(EV_KEY, input->evbit);
set_bit(BTN_0, input->keybit);
if ((ret = input_register_device(input)) < 0)
goto error;
dev->input = input;
return 0;
error:
input_free_device(input);
kfree(phys);
return ret;
}
static void uvc_input_cleanup(struct uvc_device *dev)
{
if (dev->input)
input_unregister_device(dev->input);
}
static void uvc_input_report_key(struct uvc_device *dev, unsigned int code,
int value)
{
if (dev->input)
input_report_key(dev->input, code, value);
}
#else
#define uvc_input_init(dev)
#define uvc_input_cleanup(dev)
#define uvc_input_report_key(dev, code, value)
#endif /* CONFIG_USB_VIDEO_CLASS_INPUT_EVDEV */
/* --------------------------------------------------------------------------
* Status interrupt endpoint
*/
static void uvc_event_streaming(struct uvc_device *dev, __u8 *data, int len)
{
if (len < 3) {
uvc_trace(UVC_TRACE_STATUS, "Invalid streaming status event "
"received.\n");
return;
}
if (data[2] == 0) {
if (len < 4)
return;
uvc_trace(UVC_TRACE_STATUS, "Button (intf %u) %s len %d\n",
data[1], data[3] ? "pressed" : "released", len);
uvc_input_report_key(dev, BTN_0, data[3]);
} else {
uvc_trace(UVC_TRACE_STATUS, "Stream %u error event %02x %02x "
"len %d.\n", data[1], data[2], data[3], len);
}
}
static void uvc_event_control(struct uvc_device *dev, __u8 *data, int len)
{
char *attrs[3] = { "value", "info", "failure" };
if (len < 6 || data[2] != 0 || data[4] > 2) {
uvc_trace(UVC_TRACE_STATUS, "Invalid control status event "
"received.\n");
return;
}
uvc_trace(UVC_TRACE_STATUS, "Control %u/%u %s change len %d.\n",
data[1], data[3], attrs[data[4]], len);
}
static void uvc_status_complete(struct urb *urb)
{
struct uvc_device *dev = urb->context;
int len, ret;
switch (urb->status) {
case 0:
break;
case -ENOENT: /* usb_kill_urb() called. */
case -ECONNRESET: /* usb_unlink_urb() called. */
case -ESHUTDOWN: /* The endpoint is being disabled. */
case -EPROTO: /* Device is disconnected (reported by some
* host controller). */
return;
default:
uvc_printk(KERN_WARNING, "Non-zero status (%d) in status "
"completion handler.\n", urb->status);
return;
}
len = urb->actual_length;
if (len > 0) {
switch (dev->status[0] & 0x0f) {
case UVC_STATUS_TYPE_CONTROL:
uvc_event_control(dev, dev->status, len);
break;
case UVC_STATUS_TYPE_STREAMING:
uvc_event_streaming(dev, dev->status, len);
break;
default:
uvc_printk(KERN_INFO, "unknown event type %u.\n",
dev->status[0]);
break;
}
}
/* Resubmit the URB. */
urb->interval = dev->int_ep->desc.bInterval;
if ((ret = usb_submit_urb(urb, GFP_ATOMIC)) < 0) {
uvc_printk(KERN_ERR, "Failed to resubmit status URB (%d).\n",
ret);
}
}
int uvc_status_init(struct uvc_device *dev)
{
struct usb_host_endpoint *ep = dev->int_ep;
unsigned int pipe;
int interval;
if (ep == NULL)
return 0;
uvc_input_init(dev);
dev->status = kzalloc(UVC_MAX_STATUS_SIZE, GFP_KERNEL);
if (dev->status == NULL)
return -ENOMEM;
dev->int_urb = usb_alloc_urb(0, GFP_KERNEL);
if (dev->int_urb == NULL) {
kfree(dev->status);
return -ENOMEM;
}
pipe = usb_rcvintpipe(dev->udev, ep->desc.bEndpointAddress);
/* For high-speed interrupt endpoints, the bInterval value is used as
* an exponent of two. Some developers forgot about it.
*/
interval = ep->desc.bInterval;
if (interval > 16 && dev->udev->speed == USB_SPEED_HIGH &&
(dev->quirks & UVC_QUIRK_STATUS_INTERVAL))
interval = fls(interval) - 1;
usb_fill_int_urb(dev->int_urb, dev->udev, pipe,
dev->status, UVC_MAX_STATUS_SIZE, uvc_status_complete,
dev, interval);
return usb_submit_urb(dev->int_urb, GFP_KERNEL);
}
void uvc_status_cleanup(struct uvc_device *dev)
{
usb_kill_urb(dev->int_urb);
usb_free_urb(dev->int_urb);
kfree(dev->status);
uvc_input_cleanup(dev);
}
int uvc_status_suspend(struct uvc_device *dev)
{
usb_kill_urb(dev->int_urb);
return 0;
}
int uvc_status_resume(struct uvc_device *dev)
{
if (dev->int_urb == NULL)
return 0;
return usb_submit_urb(dev->int_urb, GFP_NOIO);
}