path: root/drivers/net/wireless/ralink/rt2x00/rt2x00usb.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
	Copyright (C) 2010 Willow Garage <http://www.willowgarage.com>
	Copyright (C) 2004 - 2010 Ivo van Doorn <IvDoorn@gmail.com>
	<http://rt2x00.serialmonkey.com>

 */

/*
	Module: rt2x00usb
	Abstract: rt2x00 generic usb device routines.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/usb.h>
#include <linux/bug.h>

#include "rt2x00.h"
#include "rt2x00usb.h"

static bool rt2x00usb_check_usb_error(struct rt2x00_dev *rt2x00dev, int status)
{
	if (status == -ENODEV || status == -ENOENT)
		return true;

	if (!test_bit(DEVICE_STATE_STARTED, &rt2x00dev->flags))
		return false;

	if (status == -EPROTO || status == -ETIMEDOUT)
		rt2x00dev->num_proto_errs++;
	else
		rt2x00dev->num_proto_errs = 0;

	if (rt2x00dev->num_proto_errs > 3)
		return true;

	return false;
}

/*
 * Interfacing with the HW.
 */
int rt2x00usb_vendor_request(struct rt2x00_dev *rt2x00dev,
			     const u8 request, const u8 requesttype,
			     const u16 offset, const u16 value,
			     void *buffer, const u16 buffer_length,
			     const int timeout)
{
	struct usb_device *usb_dev = to_usb_device_intf(rt2x00dev->dev);
	int status;
	unsigned int pipe =
	    (requesttype == USB_VENDOR_REQUEST_IN) ?
	    usb_rcvctrlpipe(usb_dev, 0) : usb_sndctrlpipe(usb_dev, 0);
	unsigned long expire = jiffies + msecs_to_jiffies(timeout);

	if (!test_bit(DEVICE_STATE_PRESENT, &rt2x00dev->flags))
		return -ENODEV;

	do {
		status = usb_control_msg(usb_dev, pipe, request, requesttype,
					 value, offset, buffer, buffer_length,
					 timeout / 2);
		if (status >= 0)
			return 0;

		if (rt2x00usb_check_usb_error(rt2x00dev, status)) {
			/* Device has disappeared. */
			clear_bit(DEVICE_STATE_PRESENT, &rt2x00dev->flags);
			break;
		}
	} while (time_before(jiffies, expire));

	rt2x00_err(rt2x00dev,
		   "Vendor Request 0x%02x failed for offset 0x%04x with error %d\n",
		   request, offset, status);

	return status;
}
EXPORT_SYMBOL_GPL(rt2x00usb_vendor_request);

int rt2x00usb_vendor_req_buff_lock(struct rt2x00_dev *rt2x00dev,
				   const u8 request, const u8 requesttype,
				   const u16 offset, void *buffer,
				   const u16 buffer_length, const int timeout)
{
	int status;

	BUG_ON(!mutex_is_locked(&rt2x00dev->csr_mutex));

	/*
	 * Check for Cache availability.
	 */
	if (unlikely(!rt2x00dev->csr.cache || buffer_length > CSR_CACHE_SIZE)) {
		rt2x00_err(rt2x00dev, "CSR cache not available\n");
		return -ENOMEM;
	}

	if (requesttype == USB_VENDOR_REQUEST_OUT)
		memcpy(rt2x00dev->csr.cache, buffer, buffer_length);

	status = rt2x00usb_vendor_request(rt2x00dev, request, requesttype,
					  offset, 0, rt2x00dev->csr.cache,
					  buffer_length, timeout);

	if (!status && requesttype == USB_VENDOR_REQUEST_IN)
		memcpy(buffer, rt2x00dev->csr.cache, buffer_length);

	return status;
}
EXPORT_SYMBOL_GPL(rt2x00usb_vendor_req_buff_lock);

int rt2x00usb_vendor_request_buff(struct rt2x00_dev *rt2x00dev,
				  const u8 request, const u8 requesttype,
				  const u16 offset, void *buffer,
				  const u16 buffer_length)
{
	int status = 0;
	u8 *tb;
	u16 off, len, bsize;

	mutex_lock(&rt2x00dev->csr_mutex);

	tb  = (u8 *)buffer;
	off = offset;
	len = buffer_length;
	while (len && !status) {
		bsize = min_t(u16, CSR_CACHE_SIZE, len);
		status = rt2x00usb_vendor_req_buff_lock(rt2x00dev, request,
							requesttype, off, tb,
							bsize, REGISTER_TIMEOUT);

		tb  += bsize;
		len -= bsize;
		off += bsize;
	}

	mutex_unlock(&rt2x00dev->csr_mutex);

	return status;
}
EXPORT_SYMBOL_GPL(rt2x00usb_vendor_request_buff);

int rt2x00usb_regbusy_read(struct rt2x00_dev *rt2x00dev,
			   const unsigned int offset,
			   const struct rt2x00_field32 field,
			   u32 *reg)
{
	unsigned int i;

	if (!test_bit(DEVICE_STATE_PRESENT, &rt2x00dev->flags))
		return -ENODEV;

	for (i = 0;