[RT2x00]: add driver for Ralink wireless hardware

Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/wireless/rt2x00/rt2x00usb.c b/drivers/net/wireless/rt2x00/rt2x00usb.c
new file mode 100644
index 0000000..a0f05ca
--- /dev/null
+++ b/drivers/net/wireless/rt2x00/rt2x00usb.c
@@ -0,0 +1,595 @@
+/*
+	Copyright (C) 2004 - 2007 rt2x00 SourceForge Project
+	<http://rt2x00.serialmonkey.com>
+
+	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.
+ */
+
+/*
+	Module: rt2x00usb
+	Abstract: rt2x00 generic usb device routines.
+ */
+
+/*
+ * Set enviroment defines for rt2x00.h
+ */
+#define DRV_NAME "rt2x00usb"
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/usb.h>
+
+#include "rt2x00.h"
+#include "rt2x00usb.h"
+
+/*
+ * Interfacing with the HW.
+ */
+int rt2x00usb_vendor_request(const struct rt2x00_dev *rt2x00dev,
+			     const u8 request, const u8 requesttype,
+			     const u16 offset, const u16 value,
+			     void *buffer, const u16 buffer_length,
+			     u16 timeout)
+{
+	struct usb_device *usb_dev =
+	    interface_to_usbdev(rt2x00dev_usb(rt2x00dev));
+	int status;
+	unsigned int i;
+	unsigned int pipe =
+	    (requesttype == USB_VENDOR_REQUEST_IN) ?
+	    usb_rcvctrlpipe(usb_dev, 0) : usb_sndctrlpipe(usb_dev, 0);
+
+	for (i = 0; i < REGISTER_BUSY_COUNT; i++) {
+		status = usb_control_msg(usb_dev, pipe, request, requesttype,
+					 value, offset, buffer, buffer_length,
+					 timeout);
+		if (status >= 0)
+			return 0;
+
+		/*
+		 * Check for errors,
+		 * -ETIMEDOUT: We need a bit more time to complete.
+		 * -ENODEV: Device has disappeared, no point continuing.
+		 */
+		if (status == -ETIMEDOUT)
+			timeout *= 2;
+		else if (status == -ENODEV)
+			break;
+	}
+
+	ERROR(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_request_buff(const struct rt2x00_dev *rt2x00dev,
+				  const u8 request, const u8 requesttype,
+				  const u16 offset, void *buffer,
+				  const u16 buffer_length, u16 timeout)
+{
+	int status;
+
+	/*
+	 * Check for Cache availability.
+	 */
+	if (unlikely(!rt2x00dev->csr_cache || buffer_length > CSR_CACHE_SIZE)) {
+		ERROR(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_request_buff);
+
+/*
+ * TX data handlers.
+ */
+static void rt2x00usb_interrupt_txdone(struct urb *urb)
+{
+	struct data_entry *entry = (struct data_entry *)urb->context;
+	struct data_ring *ring = entry->ring;
+	struct rt2x00_dev *rt2x00dev = ring->rt2x00dev;
+	struct data_desc *txd = (struct data_desc *)entry->skb->data;
+	u32 word;
+	int tx_status;
+
+	if (!test_bit(DEVICE_ENABLED_RADIO, &rt2x00dev->flags) ||
+	    !__test_and_clear_bit(ENTRY_OWNER_NIC, &entry->flags))
+		return;
+
+	rt2x00_desc_read(txd, 0, &word);
+
+	/*
+	 * Remove the descriptor data from the buffer.
+	 */
+	skb_pull(entry->skb, ring->desc_size);
+
+	/*
+	 * Obtain the status about this packet.
+	 */
+	tx_status = !urb->status ? TX_SUCCESS : TX_FAIL_RETRY;
+
+	rt2x00lib_txdone(entry, tx_status, 0);
+
+	/*
+	 * Make this entry available for reuse.
+	 */
+	entry->flags = 0;
+	rt2x00_ring_index_done_inc(entry->ring);
+
+	/*
+	 * If the data ring was full before the txdone handler
+	 * we must make sure the packet queue in the mac80211 stack
+	 * is reenabled when the txdone handler has finished.
+	 */
+	if (!rt2x00_ring_full(ring))
+		ieee80211_wake_queue(rt2x00dev->hw,
+				     entry->tx_status.control.queue);
+}
+
+int rt2x00usb_write_tx_data(struct rt2x00_dev *rt2x00dev,
+			    struct data_ring *ring, struct sk_buff *skb,
+			    struct ieee80211_tx_control *control)
+{
+	struct usb_device *usb_dev =
+	    interface_to_usbdev(rt2x00dev_usb(rt2x00dev));
+	struct ieee80211_hdr *ieee80211hdr = (struct ieee80211_hdr *)skb->data;
+	struct data_entry *entry = rt2x00_get_data_entry(ring);
+	u32 length = skb->len;
+
+	if (rt2x00_ring_full(ring)) {
+		ieee80211_stop_queue(rt2x00dev->hw, control->queue);
+		return -EINVAL;
+	}
+
+	if (test_bit(ENTRY_OWNER_NIC, &entry->flags)) {
+		ERROR(rt2x00dev,
+		      "Arrived at non-free entry in the non-full queue %d.\n"
+		      "Please file bug report to %s.\n",
+		      control->queue, DRV_PROJECT);
+		ieee80211_stop_queue(rt2x00dev->hw, control->queue);
+		return -EINVAL;
+	}
+
+	/*
+	 * Add the descriptor in front of the skb.
+	 */
+	skb_push(skb, rt2x00dev->hw->extra_tx_headroom);
+	memset(skb->data, 0x00, rt2x00dev->hw->extra_tx_headroom);
+
+	rt2x00lib_write_tx_desc(rt2x00dev, (struct data_desc *)skb->data,
+				ieee80211hdr, length, control);
+	memcpy(&entry->tx_status.control, control, sizeof(*control));
+	entry->skb = skb;
+
+	/*
+	 * Length passed to usb_fill_urb cannot be an odd number,
+	 * so add 1 byte to make it even.
+	 */
+	length += rt2x00dev->hw->extra_tx_headroom;
+	if (length % 2)
+		length++;
+
+	__set_bit(ENTRY_OWNER_NIC, &entry->flags);
+	usb_fill_bulk_urb(entry->priv, usb_dev,
+			  usb_sndbulkpipe(usb_dev, 1),
+			  skb->data, length, rt2x00usb_interrupt_txdone, entry);
+	usb_submit_urb(entry->priv, GFP_ATOMIC);
+
+	rt2x00_ring_index_inc(ring);
+
+	if (rt2x00_ring_full(ring))
+		ieee80211_stop_queue(rt2x00dev->hw, control->queue);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(rt2x00usb_write_tx_data);
+
+/*
+ * RX data handlers.
+ */
+static void rt2x00usb_interrupt_rxdone(struct urb *urb)
+{
+	struct data_entry *entry = (struct data_entry *)urb->context;
+	struct data_ring *ring = entry->ring;
+	struct rt2x00_dev *rt2x00dev = ring->rt2x00dev;
+	struct sk_buff *skb;
+	int retval;
+	int signal;
+	int rssi;
+	int ofdm;
+	int size;
+	int frame_size;
+
+	if (!test_bit(DEVICE_ENABLED_RADIO, &rt2x00dev->flags) ||
+	    !test_and_clear_bit(ENTRY_OWNER_NIC, &entry->flags))
+		return;
+
+	/*
+	 * Check if the received data is simply too small
+	 * to be actually valid, or if the urb is signaling
+	 * a problem.
+	 */
+	if (urb->actual_length < entry->ring->desc_size || urb->status)
+		goto skip_entry;
+
+	retval = rt2x00dev->ops->lib->fill_rxdone(entry, &signal, &rssi,
+						  &ofdm, &size);
+	if (retval)
+		goto skip_entry;
+
+	/*
+	 * Allocate a new sk buffer to replace the current one.
+	 * If allocation fails, we should drop the current frame
+	 * so we can recycle the existing sk buffer for the new frame.
+	 */
+	frame_size = entry->ring->data_size + entry->ring->desc_size;
+	skb = dev_alloc_skb(frame_size + NET_IP_ALIGN);
+	if (!skb)
+		goto skip_entry;
+
+	skb_reserve(skb, NET_IP_ALIGN);
+	skb_put(skb, frame_size);
+
+	/*
+	 * Trim the skb_buffer to only contain the valid
+	 * frame data (so ignore the device's descriptor).
+	 */
+	skb_trim(entry->skb, size);
+
+	/*
+	 * Send the frame to rt2x00lib for further processing.
+	 */
+	rt2x00lib_rxdone(entry, entry->skb, signal, rssi, ofdm);
+
+	/*
+	 * Replace current entry's skb with the newly allocated one,
+	 * and reinitialize the urb.
+	 */
+	entry->skb = skb;
+	urb->transfer_buffer = entry->skb->data;
+	urb->transfer_buffer_length = entry->skb->len;
+
+skip_entry:
+	if (test_bit(DEVICE_ENABLED_RADIO, &ring->rt2x00dev->flags)) {
+		__set_bit(ENTRY_OWNER_NIC, &entry->flags);
+		usb_submit_urb(urb, GFP_ATOMIC);
+	}
+
+	rt2x00_ring_index_inc(ring);
+}
+
+/*
+ * Radio handlers
+ */
+void rt2x00usb_enable_radio(struct rt2x00_dev *rt2x00dev)
+{
+	struct usb_device *usb_dev =
+	    interface_to_usbdev(rt2x00dev_usb(rt2x00dev));
+	struct data_ring *ring;
+	struct data_entry *entry;
+	unsigned int i;
+
+	/*
+	 * Initialize the TX rings
+	 */
+	txringall_for_each(rt2x00dev, ring) {
+		for (i = 0; i < ring->stats.limit; i++)
+			ring->entry[i].flags = 0;
+
+		rt2x00_ring_index_clear(ring);
+	}
+
+	/*
+	 * Initialize and start the RX ring.
+	 */
+	rt2x00_ring_index_clear(rt2x00dev->rx);
+
+	for (i = 0; i < rt2x00dev->rx->stats.limit; i++) {
+		entry = &rt2x00dev->rx->entry[i];
+
+		usb_fill_bulk_urb(entry->priv, usb_dev,
+				  usb_rcvbulkpipe(usb_dev, 1),
+				  entry->skb->data, entry->skb->len,
+				  rt2x00usb_interrupt_rxdone, entry);
+
+		__set_bit(ENTRY_OWNER_NIC, &entry->flags);
+		usb_submit_urb(entry->priv, GFP_ATOMIC);
+	}
+}
+EXPORT_SYMBOL_GPL(rt2x00usb_enable_radio);
+
+void rt2x00usb_disable_radio(struct rt2x00_dev *rt2x00dev)
+{
+	struct data_ring *ring;
+	unsigned int i;
+
+	rt2x00usb_vendor_request_sw(rt2x00dev, USB_RX_CONTROL, 0x0000, 0x0000,
+				    REGISTER_TIMEOUT);
+
+	/*
+	 * Cancel all rings.
+	 */
+	ring_for_each(rt2x00dev, ring) {
+		for (i = 0; i < ring->stats.limit; i++)
+			usb_kill_urb(ring->entry[i].priv);
+	}
+}
+EXPORT_SYMBOL_GPL(rt2x00usb_disable_radio);
+
+/*
+ * Device initialization handlers.
+ */
+static int rt2x00usb_alloc_urb(struct rt2x00_dev *rt2x00dev,
+			       struct data_ring *ring)
+{
+	unsigned int i;
+
+	/*
+	 * Allocate the URB's
+	 */
+	for (i = 0; i < ring->stats.limit; i++) {
+		ring->entry[i].priv = usb_alloc_urb(0, GFP_KERNEL);
+		if (!ring->entry[i].priv)
+			return -ENOMEM;
+	}
+
+	return 0;
+}
+
+static void rt2x00usb_free_urb(struct rt2x00_dev *rt2x00dev,
+			       struct data_ring *ring)
+{
+	unsigned int i;
+
+	if (!ring->entry)
+		return;
+
+	for (i = 0; i < ring->stats.limit; i++) {
+		usb_kill_urb(ring->entry[i].priv);
+		usb_free_urb(ring->entry[i].priv);
+		if (ring->entry[i].skb)
+			kfree_skb(ring->entry[i].skb);
+	}
+}
+
+int rt2x00usb_initialize(struct rt2x00_dev *rt2x00dev)
+{
+	struct data_ring *ring;
+	struct sk_buff *skb;
+	unsigned int entry_size;
+	unsigned int i;
+	int status;
+
+	/*
+	 * Allocate DMA
+	 */
+	ring_for_each(rt2x00dev, ring) {
+		status = rt2x00usb_alloc_urb(rt2x00dev, ring);
+		if (status)
+			goto exit;
+	}
+
+	/*
+	 * For the RX ring, skb's should be allocated.
+	 */
+	entry_size = rt2x00dev->rx->data_size + rt2x00dev->rx->desc_size;
+	for (i = 0; i < rt2x00dev->rx->stats.limit; i++) {
+		skb = dev_alloc_skb(NET_IP_ALIGN + entry_size);
+		if (!skb)
+			goto exit;
+
+		skb_reserve(skb, NET_IP_ALIGN);
+		skb_put(skb, entry_size);
+
+		rt2x00dev->rx->entry[i].skb = skb;
+	}
+
+	return 0;
+
+exit:
+	rt2x00usb_uninitialize(rt2x00dev);
+
+	return status;
+}
+EXPORT_SYMBOL_GPL(rt2x00usb_initialize);
+
+void rt2x00usb_uninitialize(struct rt2x00_dev *rt2x00dev)
+{
+	struct data_ring *ring;
+
+	ring_for_each(rt2x00dev, ring)
+		rt2x00usb_free_urb(rt2x00dev, ring);
+}
+EXPORT_SYMBOL_GPL(rt2x00usb_uninitialize);
+
+/*
+ * USB driver handlers.
+ */
+static void rt2x00usb_free_reg(struct rt2x00_dev *rt2x00dev)
+{
+	kfree(rt2x00dev->rf);
+	rt2x00dev->rf = NULL;
+
+	kfree(rt2x00dev->eeprom);
+	rt2x00dev->eeprom = NULL;
+
+	kfree(rt2x00dev->csr_cache);
+	rt2x00dev->csr_cache = NULL;
+}
+
+static int rt2x00usb_alloc_reg(struct rt2x00_dev *rt2x00dev)
+{
+	rt2x00dev->csr_cache = kzalloc(CSR_CACHE_SIZE, GFP_KERNEL);
+	if (!rt2x00dev->csr_cache)
+		goto exit;
+
+	rt2x00dev->eeprom = kzalloc(rt2x00dev->ops->eeprom_size, GFP_KERNEL);
+	if (!rt2x00dev->eeprom)
+		goto exit;
+
+	rt2x00dev->rf = kzalloc(rt2x00dev->ops->rf_size, GFP_KERNEL);
+	if (!rt2x00dev->rf)
+		goto exit;
+
+	return 0;
+
+exit:
+	ERROR_PROBE("Failed to allocate registers.\n");
+
+	rt2x00usb_free_reg(rt2x00dev);
+
+	return -ENOMEM;
+}
+
+int rt2x00usb_probe(struct usb_interface *usb_intf,
+		    const struct usb_device_id *id)
+{
+	struct usb_device *usb_dev = interface_to_usbdev(usb_intf);
+	struct rt2x00_ops *ops = (struct rt2x00_ops *)id->driver_info;
+	struct ieee80211_hw *hw;
+	struct rt2x00_dev *rt2x00dev;
+	int retval;
+
+	usb_dev = usb_get_dev(usb_dev);
+
+	hw = ieee80211_alloc_hw(sizeof(struct rt2x00_dev), ops->hw);
+	if (!hw) {
+		ERROR_PROBE("Failed to allocate hardware.\n");
+		retval = -ENOMEM;
+		goto exit_put_device;
+	}
+
+	usb_set_intfdata(usb_intf, hw);
+
+	rt2x00dev = hw->priv;
+	rt2x00dev->dev = usb_intf;
+	rt2x00dev->ops = ops;
+	rt2x00dev->hw = hw;
+
+	retval = rt2x00usb_alloc_reg(rt2x00dev);
+	if (retval)
+		goto exit_free_device;
+
+	retval = rt2x00lib_probe_dev(rt2x00dev);
+	if (retval)
+		goto exit_free_reg;
+
+	return 0;
+
+exit_free_reg:
+	rt2x00usb_free_reg(rt2x00dev);
+
+exit_free_device:
+	ieee80211_free_hw(hw);
+
+exit_put_device:
+	usb_put_dev(usb_dev);
+
+	usb_set_intfdata(usb_intf, NULL);
+
+	return retval;
+}
+EXPORT_SYMBOL_GPL(rt2x00usb_probe);
+
+void rt2x00usb_disconnect(struct usb_interface *usb_intf)
+{
+	struct ieee80211_hw *hw = usb_get_intfdata(usb_intf);
+	struct rt2x00_dev *rt2x00dev = hw->priv;
+
+	/*
+	 * Free all allocated data.
+	 */
+	rt2x00lib_remove_dev(rt2x00dev);
+	rt2x00usb_free_reg(rt2x00dev);
+	ieee80211_free_hw(hw);
+
+	/*
+	 * Free the USB device data.
+	 */
+	usb_set_intfdata(usb_intf, NULL);
+	usb_put_dev(interface_to_usbdev(usb_intf));
+}
+EXPORT_SYMBOL_GPL(rt2x00usb_disconnect);
+
+#ifdef CONFIG_PM
+int rt2x00usb_suspend(struct usb_interface *usb_intf, pm_message_t state)
+{
+	struct ieee80211_hw *hw = usb_get_intfdata(usb_intf);
+	struct rt2x00_dev *rt2x00dev = hw->priv;
+	int retval;
+
+	retval = rt2x00lib_suspend(rt2x00dev, state);
+	if (retval)
+		return retval;
+
+	rt2x00usb_free_reg(rt2x00dev);
+
+	/*
+	 * Decrease usbdev refcount.
+	 */
+	usb_put_dev(interface_to_usbdev(usb_intf));
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(rt2x00usb_suspend);
+
+int rt2x00usb_resume(struct usb_interface *usb_intf)
+{
+	struct ieee80211_hw *hw = usb_get_intfdata(usb_intf);
+	struct rt2x00_dev *rt2x00dev = hw->priv;
+	int retval;
+
+	usb_get_dev(interface_to_usbdev(usb_intf));
+
+	retval = rt2x00usb_alloc_reg(rt2x00dev);
+	if (retval)
+		return retval;
+
+	retval = rt2x00lib_resume(rt2x00dev);
+	if (retval)
+		goto exit_free_reg;
+
+	return 0;
+
+exit_free_reg:
+	rt2x00usb_free_reg(rt2x00dev);
+
+	return retval;
+}
+EXPORT_SYMBOL_GPL(rt2x00usb_resume);
+#endif /* CONFIG_PM */
+
+/*
+ * rt2x00pci module information.
+ */
+MODULE_AUTHOR(DRV_PROJECT);
+MODULE_VERSION(DRV_VERSION);
+MODULE_DESCRIPTION("rt2x00 library");
+MODULE_LICENSE("GPL");