zd_usb.c

zd1211无线网卡驱动源代码

int zd_usb_enable_rx(struct zd_usb *usb)
{
	int i, r;
	struct zd_usb_rx *rx = &usb->rx;
	struct urb **urbs;

	dev_dbg_f(zd_usb_dev(usb), "\n");

	r = -ENOMEM;
	urbs = kcalloc(URBS_COUNT, sizeof(struct urb *), GFP_NOFS);
	if (!urbs)
		goto error;
	for (i = 0; i < URBS_COUNT; i++) {
		urbs[i] = alloc_urb(usb);
		if (!urbs[i])
			goto error;
	}

	ZD_ASSERT(!irqs_disabled());
	spin_lock_irq(&rx->lock);
	if (rx->urbs) {
		spin_unlock_irq(&rx->lock);
		r = 0;
		goto error;
	}
	rx->urbs = urbs;
	rx->urbs_count = URBS_COUNT;
	spin_unlock_irq(&rx->lock);

	for (i = 0; i < URBS_COUNT; i++) {
		r = usb_submit_urb(urbs[i], GFP_NOFS);
		if (r)
			goto error_submit;
	}

	return 0;
error_submit:
	for (i = 0; i < URBS_COUNT; i++) {
		usb_kill_urb(urbs[i]);
	}
	spin_lock_irq(&rx->lock);
	rx->urbs = NULL;
	rx->urbs_count = 0;
	spin_unlock_irq(&rx->lock);
error:
	if (urbs) {
		for (i = 0; i < URBS_COUNT; i++)
			free_urb(urbs[i]);
	}
	return r;
}

void zd_usb_disable_rx(struct zd_usb *usb)
{
	int i;
	unsigned long flags;
	struct urb **urbs;
	unsigned int count;
	struct zd_usb_rx *rx = &usb->rx;

	spin_lock_irqsave(&rx->lock, flags);
	urbs = rx->urbs;
	count = rx->urbs_count;
	spin_unlock_irqrestore(&rx->lock, flags);
	if (!urbs)
		return;

	for (i = 0; i < count; i++) {
		usb_kill_urb(urbs[i]);
		free_urb(urbs[i]);
	}
	kfree(urbs);

	spin_lock_irqsave(&rx->lock, flags);
	rx->urbs = NULL;
	rx->urbs_count = 0;
	spin_unlock_irqrestore(&rx->lock, flags);
}

static void tx_urb_complete(struct urb *urb, struct pt_regs *pt_regs)
{
	int r;

	switch (urb->status) {
	case 0:
		break;
	case -ESHUTDOWN:
	case -EINVAL:
	case -ENODEV:
	case -ENOENT:
	case -ECONNRESET:
	case -EPIPE:
		dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
		break;
	default:
		dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
		goto resubmit;
	}
free_urb:
	usb_buffer_free(urb->dev, urb->transfer_buffer_length,
		        urb->transfer_buffer, urb->transfer_dma);
	usb_free_urb(urb);
	return;
resubmit:
	r = usb_submit_urb(urb, GFP_ATOMIC);
	if (r) {
		dev_dbg_f(urb_dev(urb), "error resubmit urb %p %d\n", urb, r);
		goto free_urb;
	}
}

/* Puts the frame on the USB endpoint. It doesn't wait for
 * completion. The frame must contain the control set.
 */
int zd_usb_tx(struct zd_usb *usb, const u8 *frame, unsigned int length)
{
	int r;
	struct usb_device *udev = zd_usb_to_usbdev(usb);
	struct urb *urb;
	void *buffer;

	urb = usb_alloc_urb(0, GFP_ATOMIC);
	if (!urb) {
		r = -ENOMEM;
		goto out;
	}

	buffer = usb_buffer_alloc(zd_usb_to_usbdev(usb), length, GFP_ATOMIC,
		                  &urb->transfer_dma);
	if (!buffer) {
		r = -ENOMEM;
		goto error_free_urb;
	}
	memcpy(buffer, frame, length);

	usb_fill_bulk_urb(urb, udev, usb_sndbulkpipe(udev, EP_DATA_OUT),
		          buffer, length, tx_urb_complete, NULL);
	urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;

	r = usb_submit_urb(urb, GFP_ATOMIC);
	if (r)
		goto error;
	return 0;
error:
	usb_buffer_free(zd_usb_to_usbdev(usb), length, buffer,
		        urb->transfer_dma);
error_free_urb:
	usb_free_urb(urb);
out:
	return r;
}

static inline void init_usb_interrupt(struct zd_usb *usb)
{
	struct zd_usb_interrupt *intr = &usb->intr;

	spin_lock_init(&intr->lock);
	intr->interval = int_urb_interval(zd_usb_to_usbdev(usb));
	init_completion(&intr->read_regs.completion);
	intr->read_regs.cr_int_addr = cpu_to_le16(usb_addr(usb, CR_INTERRUPT));
}

static inline void init_usb_rx(struct zd_usb *usb)
{
	struct zd_usb_rx *rx = &usb->rx;
	spin_lock_init(&rx->lock);
	if (interface_to_usbdev(usb->intf)->speed == USB_SPEED_HIGH) {
		rx->usb_packet_size = 512;
	} else {
		rx->usb_packet_size = 64;
	}
	ZD_ASSERT(rx->fragment_length == 0);
}

static inline void init_usb_tx(struct zd_usb *usb)
{
	/* FIXME: at this point we will allocate a fixed number of urb's for
	 * use in a cyclic scheme */
}

void zd_usb_init(struct zd_usb *usb, struct net_device *netdev,
	         struct usb_interface *intf)
{
	memset(usb, 0, sizeof(*usb));
	usb->intf = usb_get_intf(intf);
	usb_set_intfdata(usb->intf, netdev);
	init_usb_interrupt(usb);
	init_usb_tx(usb);
	init_usb_rx(usb);
}

int zd_usb_init_hw(struct zd_usb *usb)
{
	int r;
	struct zd_chip *chip = zd_usb_to_chip(usb);

	ZD_ASSERT(mutex_is_locked(&chip->mutex));
	r = zd_ioread16_locked(chip, &usb->fw_base_offset,
		        USB_REG((u16)FW_BASE_ADDR_OFFSET));
	if (r)
		return r;
	dev_dbg_f(zd_usb_dev(usb), "fw_base_offset: %#06hx\n",
		 usb->fw_base_offset);

	return 0;
}

void zd_usb_clear(struct zd_usb *usb)
{
	usb_set_intfdata(usb->intf, NULL);
	usb_put_intf(usb->intf);
	memset(usb, 0, sizeof(*usb));
	/* FIXME: usb_interrupt, usb_tx, usb_rx? */
}

static const char *speed(enum usb_device_speed speed)
{
	switch (speed) {
	case USB_SPEED_LOW:
		return "low";
	case USB_SPEED_FULL:
		return "full";
	case USB_SPEED_HIGH:
		return "high";
	default:
		return "unknown speed";
	}
}

static int scnprint_id(struct usb_device *udev, char *buffer, size_t size)
{
	return scnprintf(buffer, size, "%04hx:%04hx v%04hx %s",
		le16_to_cpu(udev->descriptor.idVendor),
		le16_to_cpu(udev->descriptor.idProduct),
		get_bcdDevice(udev),
		speed(udev->speed));
}

int zd_usb_scnprint_id(struct zd_usb *usb, char *buffer, size_t size)
{
	struct usb_device *udev = interface_to_usbdev(usb->intf);
	return scnprint_id(udev, buffer, size);
}

#ifdef DEBUG
static void print_id(struct usb_device *udev)
{
	char buffer[40];

	scnprint_id(udev, buffer, sizeof(buffer));
	buffer[sizeof(buffer)-1] = 0;
	dev_dbg_f(&udev->dev, "%s\n", buffer);
}
#else
#define print_id(udev) do { } while (0)
#endif

static int probe(struct usb_interface *intf, const struct usb_device_id *id)
{
	int r;
	struct usb_device *udev = interface_to_usbdev(intf);
	struct net_device *netdev = NULL;

	print_id(udev);

	switch (udev->speed) {
	case USB_SPEED_LOW:
	case USB_SPEED_FULL:
	case USB_SPEED_HIGH:
		break;
	default:
		dev_dbg_f(&intf->dev, "Unknown USB speed\n");
		r = -ENODEV;
		goto error;
	}

	netdev = zd_netdev_alloc(intf);
	if (netdev == NULL) {
		r = -ENOMEM;
		goto error;
	}

	r = upload_firmware(udev, id->driver_info);
	if (r) {
		dev_err(&intf->dev,
		       "couldn't load firmware. Error number %d\n", r);
		goto error;
	}

	r = usb_reset_configuration(udev);
	if (r) {
		dev_dbg_f(&intf->dev,
			"couldn't reset configuration. Error number %d\n", r);
		goto error;
	}

	/* At this point the interrupt endpoint is not generally enabled. We
	 * save the USB bandwidth until the network device is opened. But
	 * notify that the initialization of the MAC will require the
	 * interrupts to be temporary enabled.
	 */
	r = zd_mac_init_hw(zd_netdev_mac(netdev), id->driver_info);
	if (r) {
		dev_dbg_f(&intf->dev,
		         "couldn't initialize mac. Error number %d\n", r);
		goto error;
	}

	r = register_netdev(netdev);
	if (r) {
		dev_dbg_f(&intf->dev,
			 "couldn't register netdev. Error number %d\n", r);
		goto error;
	}

	dev_dbg_f(&intf->dev, "successful\n");
	dev_info(&intf->dev,"%s\n", netdev->name);
	return 0;
error:
	usb_reset_device(interface_to_usbdev(intf));
	zd_netdev_free(netdev);
	return r;
}

static void disconnect(struct usb_interface *intf)
{
	struct net_device *netdev = zd_intf_to_netdev(intf);
	struct zd_mac *mac = zd_netdev_mac(netdev);
	struct zd_usb *usb = &mac->chip.usb;

	dev_dbg_f(zd_usb_dev(usb), "\n");

	zd_netdev_disconnect(netdev);

	/* Just in case something has gone wrong! */
	zd_usb_disable_rx(usb);
	zd_usb_disable_int(usb);

	/* If the disconnect has been caused by a removal of the
	 * driver module, the reset allows reloading of the driver. If the
	 * reset will not be executed here, the upload of the firmware in the
	 * probe function caused by the reloading of the driver will fail.
	 */
	usb_reset_device(interface_to_usbdev(intf));

	/* If somebody still waits on this lock now, this is an error. */
	zd_netdev_free(netdev);
	dev_dbg(&intf->dev, "disconnected\n");
}

static struct usb_driver driver = {
	.name		= "zd1211rw",
	.id_table	= usb_ids,
	.probe		= probe,
	.disconnect	= disconnect,
};

static int __init usb_init(void)
{
	int r;

	pr_debug("usb_init()\n");

	r = usb_register(&driver);
	if (r) {
		printk(KERN_ERR "usb_register() failed. Error number %d\n", r);
		return r;
	}

	pr_debug("zd1211rw initialized\n");
	return 0;
}

static void __exit usb_exit(void)
{
	pr_debug("usb_exit()\n");
	usb_deregister(&driver);
}

module_init(usb_init);
module_exit(usb_exit);

static int usb_int_regs_length(unsigned int count)
{
	return sizeof(struct usb_int_regs) + count * sizeof(struct reg_data);
}

static void prepare_read_regs_int(struct zd_usb *usb)
{
	struct zd_usb_interrupt *intr = &usb->intr;

	spin_lock(&intr->lock);
	intr->read_regs_enabled = 1;
	INIT_COMPLETION(intr->read_regs.completion);
	spin_unlock(&intr->lock);
}

static int get_results(struct zd_usb *usb, u16 *values,
	               struct usb_req_read_regs *req, unsigned int count)
{
	int r;
	int i;
	struct zd_usb_interrupt *intr = &usb->intr;
	struct read_regs_int *rr = &intr->read_regs;
	struct usb_int_regs *regs = (struct usb_int_regs *)rr->buffer;

	spin_lock(&intr->lock);

	r = -EIO;
	/* The created block size seems to be larger than expected.
	 * However results appear to be correct.
	 */
	if (rr->length < usb_int_regs_length(count)) {
		dev_dbg_f(zd_usb_dev(usb),
			 "error: actual length %d less than expected %d\n",
			 rr->length, usb_int_regs_length(count));
		goto error_unlock;
	}
	if (rr->length > sizeof(rr->buffer)) {
		dev_dbg_f(zd_usb_dev(usb),
			 "error: actual length %d exceeds buffer size %zu\n",
			 rr->length, sizeof(rr->buffer));
		goto error_unlock;
	}

	for (i = 0; i < count; i++) {
		struct reg_data *rd = &regs->regs[i];
		if (rd->addr != req->addr[i]) {
			dev_dbg_f(zd_usb_dev(usb),
				 "rd[%d] addr %#06hx expected %#06hx\n", i,
				 le16_to_cpu(rd->addr),
				 le16_to_cpu(req->addr[i]));
			goto error_unlock;
		}
		values[i] = le16_to_cpu(rd->value);
	}

	r = 0;
error_unlock:
	spin_unlock(&intr->lock);
	return r;
}

int zd_usb_ioread16v(struct zd_usb *usb, u16 *values,
	             const zd_addr_t *addresses, unsigned int count)
{
	int r;
	int i, req_len, actual_req_len;
	struct usb_device *udev;
	struct usb_req_read_regs *req = NULL;
	unsigned long timeout;

	if (count < 1) {
		dev_dbg_f(zd_usb_dev(usb), "error: count is zero\n");
		return -EINVAL;
	}
	if (count > USB_MAX_IOREAD16_COUNT) {
		dev_dbg_f(zd_usb_dev(usb),
			 "error: count %u exceeds possible max %u\n",
			 count, USB_MAX_IOREAD16_COUNT);
		return -EINVAL;
	}
	if (in_atomic()) {
		dev_dbg_f(zd_usb_dev(usb),
			 "error: io in atomic context not supported\n");
		return -EWOULDBLOCK;
	}
	if (!usb_int_enabled(usb)) {
		 dev_dbg_f(zd_usb_dev(usb),
			  "error: usb interrupt not enabled\n");
		return -EWOULDBLOCK;
	}

	req_len = sizeof(struct usb_req_read_regs) + count * sizeof(__le16);
	req = kmalloc(req_len, GFP_NOFS);
	if (!req)
		return -ENOMEM;
	req->id = cpu_to_le16(USB_REQ_READ_REGS);
	for (i = 0; i < count; i++)
		req->addr[i] = cpu_to_le16(usb_addr(usb, addresses[i]));

	udev = zd_usb_to_usbdev(usb);
	prepare_read_regs_int(usb);
	r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, EP_REGS_OUT),
		         req, req_len, &actual_req_len, 1000 /* ms */);
	if (r) {
		dev_dbg_f(zd_usb_dev(usb),
			"error in usb_bulk_msg(). Error number %d\n", r);
		goto error;
	}
	if (req_len != actual_req_len) {
		dev_dbg_f(zd_usb_dev(usb), "error in usb_bulk_msg()\n"
			" req_len %d != actual_req_len %d\n",
			req_len, actual_req_len);
		r = -EIO;
		goto error;
	}

	timeout = wait_for_completion_timeout(&usb->intr.read_regs.completion,
	                                      msecs_to_jiffies(1000));
	if (!timeout) {
		disable_read_regs_int(usb);
		dev_dbg_f(zd_usb_dev(usb), "read timed out\n");
		r = -ETIMEDOUT;
		goto error;
	}

	r = get_results(usb, values, req, count);
error:
	kfree(req);
	return r;
}

int zd_usb_iowrite16v(struct zd_usb *usb, const struct zd_ioreq16 *ioreqs,
	              unsigned int count)
{
	int r;
	struct usb_device *udev;
	struct usb_req_write_regs *req = NULL;
	int i, req_len, actual_req_len;

	if (count == 0)
		return 0;
	if (count > USB_MAX_IOWRITE16_COUNT) {
		dev_dbg_f(zd_usb_dev(usb),
			"error: count %u exceeds possible max %u\n",
			count, USB_MAX_IOWRITE16_COUNT);
		return -EINVAL;
	}
	if (in_atomic()) {
		dev_dbg_f(zd_usb_dev(usb),
			"error: io in atomic context not supported\n");
		return -EWOULDBLOCK;
	}

	req_len = sizeof(struct usb_req_write_regs) +
		  count * sizeof(struct reg_data);
	req = kmalloc(req_len, GFP_NOFS);
	if (!req)
		return -ENOMEM;

	req->id = cpu_to_le16(USB_REQ_WRITE_REGS);
	for (i = 0; i < count; i++) {
		struct reg_data *rw  = &req->reg_writes[i];
		rw->addr = cpu_to_le16(usb_addr(usb, ioreqs[i].addr));
		rw->value = cpu_to_le16(ioreqs[i].value);
	}

	udev = zd_usb_to_usbdev(usb);
	r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, EP_REGS_OUT),
		         req, req_len, &actual_req_len, 1000 /* ms */);
	if (r) {
		dev_dbg_f(zd_usb_dev(usb),
			"error in usb_bulk_msg(). Error number %d\n", r);
		goto error;
	}
	if (req_len != actual_req_len) {
		dev_dbg_f(zd_usb_dev(usb),
			"error in usb_bulk_msg()"
			" req_len %d != actual_req_len %d\n",
			req_len, actual_req_len);
		r = -EIO;
		goto error;
	}

	/* FALL-THROUGH with r == 0 */
error:
	kfree(req);
	return r;
}

int zd_usb_rfwrite(struct zd_usb *usb, u32 value, u8 bits)
{
	int r;
	struct usb_device *udev;
	struct usb_req_rfwrite *req = NULL;
	int i, req_len, actual_req_len;
	u16 bit_value_template;

	if (in_atomic()) {
		dev_dbg_f(zd_usb_dev(usb),
			"error: io in atomic context not supported\n");
		return -EWOULDBLOCK;
	}
	if (bits < USB_MIN_RFWRITE_BIT_COUNT) {
		dev_dbg_f(zd_usb_dev(usb),
			"error: bits %d are smaller than"
			" USB_MIN_RFWRITE_BIT_COUNT %d\n",
			bits, USB_MIN_RFWRITE_BIT_COUNT);
		return -EINVAL;
	}
	if (bits > USB_MAX_RFWRITE_BIT_COUNT) {
		dev_dbg_f(zd_usb_dev(usb),
			"error: bits %d exceed USB_MAX_RFWRITE_BIT_COUNT %d\n",
			bits, USB_MAX_RFWRITE_BIT_COUNT);
		return -EINVAL;
	}
#ifdef DEBUG
	if (value & (~0UL << bits)) {
		dev_dbg_f(zd_usb_dev(usb),
			"error: value %#09x has bits >= %d set\n",
			value, bits);
		return -EINVAL;
	}
#endif /* DEBUG */

	dev_dbg_f(zd_usb_dev(usb), "value %#09x bits %d\n", value, bits);

	r = zd_usb_ioread16(usb, &bit_value_template, CR203);
	if (r) {
		dev_dbg_f(zd_usb_dev(usb),
			"error %d: Couldn't read CR203\n", r);
		goto out;
	}
	bit_value_template &= ~(RF_IF_LE|RF_CLK|RF_DATA);

	req_len = sizeof(struct usb_req_rfwrite) + bits * sizeof(__le16);
	req = kmalloc(req_len, GFP_NOFS);
	if (!req)
		return -ENOMEM;

	req->id = cpu_to_le16(USB_REQ_WRITE_RF);
	/* 1: 3683a, but not used in ZYDAS driver */
	req->value = cpu_to_le16(2);
	req->bits = cpu_to_le16(bits);

	for (i = 0; i < bits; i++) {
		u16 bv = bit_value_template;
		if (value & (1 << (bits-1-i)))
			bv |= RF_DATA;
		req->bit_values[i] = cpu_to_le16(bv);
	}

	udev = zd_usb_to_usbdev(usb);
	r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, EP_REGS_OUT),
		         req, req_len, &actual_req_len, 1000 /* ms */);
	if (r) {
		dev_dbg_f(zd_usb_dev(usb),
			"error in usb_bulk_msg(). Error number %d\n", r);
		goto out;
	}
	if (req_len != actual_req_len) {
		dev_dbg_f(zd_usb_dev(usb), "error in usb_bulk_msg()"
			" req_len %d != actual_req_len %d\n",
			req_len, actual_req_len);
		r = -EIO;
		goto out;
	}

	/* FALL-THROUGH with r == 0 */
out:
	kfree(req);
	return r;
}