libertas: convert libertas driver to use an event/cmdresp queue
This patch (co-developed by Dan Williams and Holger Schurig) uses a kfifo
object for events and a swapping buffer scheme for the command response to
preserve the zero-copy semantics of the CF driver and keep memory usage low.
The main thread should only ever touch the buffer indexed by priv->resp_idx,
while the interface code is free to write to the second buffer, then swap
priv->resp_idx under the driver spinlock. The firmware specs only permit
one in-flight command, so there will only ever be one command response to
process at a time.
Signed-off-by: Holger Schurig <hs4233@mail.mn-solutions.de>
Signed-off-by: Dan Williams <dcbw@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/libertas/if_usb.c b/drivers/net/wireless/libertas/if_usb.c
index 75aed9d..8032df7 100644
--- a/drivers/net/wireless/libertas/if_usb.c
+++ b/drivers/net/wireless/libertas/if_usb.c
@@ -38,8 +38,6 @@
static int if_usb_prog_firmware(struct if_usb_card *cardp);
static int if_usb_host_to_card(struct lbs_private *priv, uint8_t type,
uint8_t *payload, uint16_t nb);
-static int if_usb_get_int_status(struct lbs_private *priv, uint8_t *);
-static int if_usb_read_event_cause(struct lbs_private *);
static int usb_tx_block(struct if_usb_card *cardp, uint8_t *payload,
uint16_t nb);
static void if_usb_free(struct if_usb_card *cardp);
@@ -233,8 +231,6 @@
cardp->priv->fw_ready = 1;
priv->hw_host_to_card = if_usb_host_to_card;
- priv->hw_get_int_status = if_usb_get_int_status;
- priv->hw_read_event_cause = if_usb_read_event_cause;
cardp->boot2_version = udev->descriptor.bcdDevice;
if_usb_submit_rx_urb(cardp);
@@ -582,7 +578,6 @@
skb_pull(skb, MESSAGE_HEADER_LEN);
lbs_process_rxed_packet(priv, skb);
- priv->upld_len = (recvlength - MESSAGE_HEADER_LEN);
}
static inline void process_cmdrequest(int recvlength, uint8_t *recvbuff,
@@ -590,6 +585,8 @@
struct if_usb_card *cardp,
struct lbs_private *priv)
{
+ u8 i;
+
if (recvlength > LBS_CMD_BUFFER_SIZE) {
lbs_deb_usbd(&cardp->udev->dev,
"The receive buffer is too large\n");
@@ -601,12 +598,15 @@
BUG();
spin_lock(&priv->driver_lock);
- cardp->usb_int_cause |= MRVDRV_CMD_UPLD_RDY;
- priv->upld_len = (recvlength - MESSAGE_HEADER_LEN);
- memcpy(priv->upld_buf, recvbuff + MESSAGE_HEADER_LEN, priv->upld_len);
+ i = (priv->resp_idx == 0) ? 1 : 0;
+ BUG_ON(priv->resp_len[i]);
+ priv->resp_len[i] = (recvlength - MESSAGE_HEADER_LEN);
+ memcpy(priv->resp_buf[i], recvbuff + MESSAGE_HEADER_LEN,
+ priv->resp_len[i]);
kfree_skb(skb);
- lbs_interrupt(priv);
+ lbs_notify_command_response(priv, i);
+
spin_unlock(&priv->driver_lock);
lbs_deb_usbd(&cardp->udev->dev,
@@ -629,6 +629,7 @@
uint8_t *recvbuff = NULL;
uint32_t recvtype = 0;
__le32 *pkt = (__le32 *)(skb->data + IPFIELD_ALIGN_OFFSET);
+ uint32_t event;
lbs_deb_enter(LBS_DEB_USB);
@@ -660,26 +661,20 @@
break;
case CMD_TYPE_INDICATION:
- /* Event cause handling */
- spin_lock(&priv->driver_lock);
-
- cardp->usb_event_cause = le32_to_cpu(pkt[1]);
-
- lbs_deb_usbd(&cardp->udev->dev,"**EVENT** 0x%X\n",
- cardp->usb_event_cause);
+ /* Event handling */
+ event = le32_to_cpu(pkt[1]);
+ lbs_deb_usbd(&cardp->udev->dev, "**EVENT** 0x%X\n", event);
+ kfree_skb(skb);
/* Icky undocumented magic special case */
- if (cardp->usb_event_cause & 0xffff0000) {
- lbs_send_tx_feedback(priv);
- spin_unlock(&priv->driver_lock);
- break;
- }
- cardp->usb_event_cause <<= 3;
- cardp->usb_int_cause |= MRVDRV_CARDEVENT;
- kfree_skb(skb);
- lbs_interrupt(priv);
- spin_unlock(&priv->driver_lock);
- goto rx_exit;
+ if (event & 0xffff0000) {
+ u32 trycount = (event & 0xffff0000) >> 16;
+
+ lbs_send_tx_feedback(priv, trycount);
+ } else
+ lbs_queue_event(priv, event & 0xFF);
+ break;
+
default:
lbs_deb_usbd(&cardp->udev->dev, "Unknown command type 0x%X\n",
recvtype);
@@ -722,30 +717,6 @@
return usb_tx_block(cardp, cardp->ep_out_buf, nb + MESSAGE_HEADER_LEN);
}
-/* called with priv->driver_lock held */
-static int if_usb_get_int_status(struct lbs_private *priv, uint8_t *ireg)
-{
- struct if_usb_card *cardp = priv->card;
-
- *ireg = cardp->usb_int_cause;
- cardp->usb_int_cause = 0;
-
- lbs_deb_usbd(&cardp->udev->dev, "Int cause is 0x%X\n", *ireg);
-
- return 0;
-}
-
-static int if_usb_read_event_cause(struct lbs_private *priv)
-{
- struct if_usb_card *cardp = priv->card;
-
- priv->eventcause = cardp->usb_event_cause;
- /* Re-submit rx urb here to avoid event lost issue */
- if_usb_submit_rx_urb(cardp);
-
- return 0;
-}
-
/**
* @brief This function issues Boot command to the Boot2 code
* @param ivalue 1:Boot from FW by USB-Download