2009-05-12 00:03:51

by Christian Lamparter

[permalink] [raw]
Subject: [PATCH 5/6] ar9170usb: introduce tx urb queue

This patch is a back-port of tx-aggregation usb code.

In the past, we didn't limit the amount of active tx_urb.
However, ar9170 only has a limited buffer reserved for
these pending data frames.

As a bonus:

we can now automatically reset the device, after the
firmware died/became stuck again.

Signed-off-by: Christian Lamparter <[email protected]>
---
diff --git a/drivers/net/wireless/ath/ar9170/ar9170.h b/drivers/net/wireless/ath/ar9170/ar9170.h
index 77dc647..cd3d1ed 100644
--- a/drivers/net/wireless/ath/ar9170/ar9170.h
+++ b/drivers/net/wireless/ath/ar9170/ar9170.h
@@ -121,6 +121,8 @@ struct ar9170 {
int (*exec_cmd)(struct ar9170 *, enum ar9170_cmd, u32 ,
void *, u32 , void *);
void (*callback_cmd)(struct ar9170 *, u32 , void *);
+ void (*reset)(struct ar9170 *);
+ int (*flush)(struct ar9170 *);

/* interface mode settings */
struct ieee80211_vif *vif;
@@ -206,6 +208,7 @@ void ar9170_rx(struct ar9170 *ar, struct sk_buff *skb);
void ar9170_unregister(struct ar9170 *ar);
void ar9170_handle_tx_status(struct ar9170 *ar, struct sk_buff *skb,
bool update_statistics, u16 tx_status);
+void ar9170_handle_command_response(struct ar9170 *ar, void *buf, u32 len);

/* MAC */
int ar9170_op_tx(struct ieee80211_hw *hw, struct sk_buff *skb);
diff --git a/drivers/net/wireless/ath/ar9170/main.c b/drivers/net/wireless/ath/ar9170/main.c
index bd50c67..a66aa7d 100644
--- a/drivers/net/wireless/ath/ar9170/main.c
+++ b/drivers/net/wireless/ath/ar9170/main.c
@@ -374,8 +374,8 @@ static void ar9170_tx_status_janitor(struct work_struct *work)
mutex_unlock(&ar->mutex);
}

-static void ar9170_handle_command_response(struct ar9170 *ar,
- void *buf, u32 len)
+void ar9170_handle_command_response(struct ar9170 *ar,
+ void *buf, u32 len)
{
struct ar9170_cmd_response *cmd = (void *) buf;

diff --git a/drivers/net/wireless/ath/ar9170/usb.c b/drivers/net/wireless/ath/ar9170/usb.c
index d7c13c0..9c21e0d 100644
--- a/drivers/net/wireless/ath/ar9170/usb.c
+++ b/drivers/net/wireless/ath/ar9170/usb.c
@@ -87,19 +87,65 @@ static struct usb_device_id ar9170_usb_ids[] = {
};
MODULE_DEVICE_TABLE(usb, ar9170_usb_ids);

+static void ar9170_usb_send_urb(struct ar9170_usb *aru)
+{
+ struct urb *urb;
+ unsigned long flags;
+
+ spin_lock_irqsave(&aru->tx_urb_lock, flags);
+ if (aru->tx_submitted_urbs >= AR9170_NUM_TX_URBS) {
+ spin_unlock_irqrestore(&aru->tx_urb_lock, flags);
+ return ;
+ }
+ aru->tx_submitted_urbs++;
+ spin_unlock_irqrestore(&aru->tx_urb_lock, flags);
+
+ urb = usb_get_from_anchor(&aru->tx_pending);
+ if (!urb)
+ return ;
+
+ aru->tx_pending_urbs--;
+
+ usb_anchor_urb(urb, &aru->tx_submitted);
+
+ if (usb_submit_urb(urb, GFP_ATOMIC)) {
+ spin_lock_irqsave(&aru->tx_urb_lock, flags);
+ aru->tx_submitted_urbs--;
+ spin_unlock_irqrestore(&aru->tx_urb_lock, flags);
+ usb_unanchor_urb(urb);
+
+ aru->common.reset(&aru->common);
+ }
+
+ usb_free_urb(urb);
+}
+
static void ar9170_usb_tx_urb_complete_free(struct urb *urb)
{
struct sk_buff *skb = urb->context;
struct ar9170_usb *aru = (struct ar9170_usb *)
usb_get_intfdata(usb_ifnum_to_if(urb->dev, 0));

- if (!aru) {
+ if (unlikely(!aru)) {
dev_kfree_skb_irq(skb);
return ;
}

- ar9170_handle_tx_status(&aru->common, skb, false,
- AR9170_TX_STATUS_COMPLETE);
+ aru->tx_submitted_urbs--;
+
+ if (!usb_anchor_empty(&aru->tx_pending))
+ ar9170_usb_send_urb(aru);
+}
+
+static void ar9170_usb_tx_urb_complete_cnt(struct urb *urb)
+{
+ struct ar9170_usb *aru = (struct ar9170_usb *)
+ usb_get_intfdata(usb_ifnum_to_if(urb->dev, 0));
+
+ aru->tx_submitted_urbs--;
+
+ if (!usb_anchor_empty(&aru->tx_pending))
+ ar9170_usb_send_urb(aru);
}

static void ar9170_usb_tx_urb_complete(struct urb *urb)
@@ -109,6 +155,7 @@ static void ar9170_usb_tx_urb_complete(struct urb *urb)
static void ar9170_usb_irq_completed(struct urb *urb)
{
struct ar9170_usb *aru = urb->context;
+ bool reset = false;

switch (urb->status) {
/* everything is fine */
@@ -123,23 +170,29 @@ static void ar9170_usb_irq_completed(struct urb *urb)
goto free;

default:
+ reset = true;
goto resubmit;
}

- print_hex_dump_bytes("ar9170 irq: ", DUMP_PREFIX_OFFSET,
- urb->transfer_buffer, urb->actual_length);
+ ar9170_handle_command_response(&aru->common,
+ urb->transfer_buffer,
+ urb->actual_length);

resubmit:
usb_anchor_urb(urb, &aru->rx_submitted);
if (usb_submit_urb(urb, GFP_ATOMIC)) {
usb_unanchor_urb(urb);
+ reset = true;
goto free;
}

- return;
+ return ;

free:
usb_buffer_free(aru->udev, 64, urb->transfer_buffer, urb->transfer_dma);
+
+ if (reset)
+ aru->common.reset(&aru->common);
}

static void ar9170_usb_rx_completed(struct urb *urb)
@@ -148,6 +201,7 @@ static void ar9170_usb_rx_completed(struct urb *urb)
struct ar9170_usb *aru = (struct ar9170_usb *)
usb_get_intfdata(usb_ifnum_to_if(urb->dev, 0));
int err;
+ bool reset = false;

if (!aru)
goto free;
@@ -165,6 +219,7 @@ static void ar9170_usb_rx_completed(struct urb *urb)
goto free;

default:
+ reset = true;
goto resubmit;
}

@@ -179,14 +234,17 @@ resubmit:
err = usb_submit_urb(urb, GFP_ATOMIC);
if (err) {
usb_unanchor_urb(urb);
- dev_kfree_skb_irq(skb);
+ reset = true;
+ goto free;
}

return ;

free:
dev_kfree_skb_irq(skb);
- return;
+
+ if (reset)
+ aru->common.reset(&aru->common);
}

static int ar9170_usb_prep_rx_urb(struct ar9170_usb *aru,
@@ -282,21 +340,39 @@ err_out:
return err;
}

-static void ar9170_usb_cancel_urbs(struct ar9170_usb *aru)
+static int ar9170_usb_flush(struct ar9170 *ar)
{
- int ret;
+ struct ar9170_usb *aru = (void *) ar;
+ int ret, err = 0;

- aru->common.state = AR9170_UNKNOWN_STATE;
+ ret = usb_wait_anchor_empty_timeout(&aru->tx_pending,
+ msecs_to_jiffies(1000));
+ if (ret == 0)
+ err = -EBUSY;

- usb_unlink_anchored_urbs(&aru->tx_submitted);
+ usb_scuttle_anchored_urbs(&aru->tx_pending);

- /* give the LED OFF command and the deauth frame a chance to air. */
+ /* lets wait a while until the tx - queues are dried out */
ret = usb_wait_anchor_empty_timeout(&aru->tx_submitted,
msecs_to_jiffies(1000));
if (ret == 0)
- dev_err(&aru->udev->dev, "kill pending tx urbs.\n");
- usb_poison_anchored_urbs(&aru->tx_submitted);
+ err = -ETIMEDOUT;
+
+ usb_kill_anchored_urbs(&aru->tx_submitted);
+ return err;
+}
+
+static void ar9170_usb_cancel_urbs(struct ar9170_usb *aru)
+{
+ int err;

+ aru->common.state = AR9170_UNKNOWN_STATE;
+
+ err = ar9170_usb_flush(&aru->common);
+ if (err)
+ dev_err(&aru->udev->dev, "stuck tx urbs!\n");
+
+ usb_poison_anchored_urbs(&aru->tx_submitted);
usb_poison_anchored_urbs(&aru->rx_submitted);
}

@@ -337,7 +413,7 @@ static int ar9170_usb_exec_cmd(struct ar9170 *ar, enum ar9170_cmd cmd,

usb_anchor_urb(urb, &aru->tx_submitted);
err = usb_submit_urb(urb, GFP_ATOMIC);
- if (err) {
+ if (unlikely(err)) {
usb_unanchor_urb(urb);
usb_free_urb(urb);
goto err_unbuf;
@@ -385,7 +461,6 @@ static int ar9170_usb_tx(struct ar9170 *ar, struct sk_buff *skb,
{
struct ar9170_usb *aru = (struct ar9170_usb *) ar;
struct urb *urb;
- int err;

if (unlikely(!IS_STARTED(ar))) {
/* Seriously, what were you drink... err... thinking!? */
@@ -399,17 +474,18 @@ static int ar9170_usb_tx(struct ar9170 *ar, struct sk_buff *skb,
usb_fill_bulk_urb(urb, aru->udev,
usb_sndbulkpipe(aru->udev, AR9170_EP_TX),
skb->data, skb->len + extra_len, (txstatus_needed ?
- ar9170_usb_tx_urb_complete :
+ ar9170_usb_tx_urb_complete_cnt :
ar9170_usb_tx_urb_complete_free), skb);
urb->transfer_flags |= URB_ZERO_PACKET;

- usb_anchor_urb(urb, &aru->tx_submitted);
- err = usb_submit_urb(urb, GFP_ATOMIC);
- if (unlikely(err))
- usb_unanchor_urb(urb);
+ usb_anchor_urb(urb, &aru->tx_pending);
+ aru->tx_pending_urbs++;

usb_free_urb(urb);
- return err;
+
+ ar9170_usb_send_urb(aru);
+
+ return 0;
}

static void ar9170_usb_callback_cmd(struct ar9170 *ar, u32 len , void *buffer)
@@ -592,10 +668,8 @@ static void ar9170_usb_stop(struct ar9170 *ar)
if (IS_ACCEPTING_CMD(ar))
aru->common.state = AR9170_STOPPED;

- /* lets wait a while until the tx - queues are dried out */
- ret = usb_wait_anchor_empty_timeout(&aru->tx_submitted,
- msecs_to_jiffies(1000));
- if (ret == 0)
+ ret = ar9170_usb_flush(ar);
+ if (ret)
dev_err(&aru->udev->dev, "kill pending tx urbs.\n");

usb_poison_anchored_urbs(&aru->tx_submitted);
@@ -656,6 +730,43 @@ err_out:
return err;
}

+static void ar9170_usb_reset_work(struct work_struct *work)
+{
+ struct ar9170_usb *aru = container_of(work, struct ar9170_usb,
+ reset_work);
+ int err;
+
+ ar9170_usb_cancel_urbs(aru);
+
+ /* let it cool down */
+ msleep(200);
+
+ usb_unpoison_anchored_urbs(&aru->rx_submitted);
+ usb_unpoison_anchored_urbs(&aru->tx_submitted);
+
+ err = ar9170_usb_init_device(aru);
+ if (err)
+ goto err_unrx;
+
+ err = ar9170_usb_open(&aru->common);
+ if (err)
+ goto err_unrx;
+
+ ieee80211_restart_hw(aru->common.hw);
+ return ;
+
+err_unrx:
+ dev_err(&aru->udev->dev, "reinitialization failed (%d)!\n", err);
+ ar9170_usb_cancel_urbs(aru);
+}
+
+static void ar9170_usb_schedule_reset(struct ar9170 *ar)
+{
+ struct ar9170_usb *aru = (void *) ar;
+
+ queue_work(ar->hw->workqueue, &aru->reset_work);
+}
+
static int ar9170_usb_probe(struct usb_interface *intf,
const struct usb_device_id *id)
{
@@ -678,12 +789,20 @@ static int ar9170_usb_probe(struct usb_interface *intf,

usb_set_intfdata(intf, aru);
SET_IEEE80211_DEV(ar->hw, &udev->dev);
+ INIT_WORK(&aru->reset_work, ar9170_usb_reset_work);

init_usb_anchor(&aru->rx_submitted);
+ init_usb_anchor(&aru->tx_pending);
init_usb_anchor(&aru->tx_submitted);
init_completion(&aru->cmd_wait);
+ spin_lock_init(&aru->tx_urb_lock);
+
+ aru->tx_pending_urbs = 0;
+ aru->tx_submitted_urbs = 0;

aru->common.stop = ar9170_usb_stop;
+ aru->common.flush = ar9170_usb_flush;
+ aru->common.reset = ar9170_usb_schedule_reset;
aru->common.open = ar9170_usb_open;
aru->common.tx = ar9170_usb_tx;
aru->common.exec_cmd = ar9170_usb_exec_cmd;
@@ -691,7 +810,7 @@ static int ar9170_usb_probe(struct usb_interface *intf,

#ifdef CONFIG_PM
udev->reset_resume = 1;
-#endif
+#endif /* CONFIG_PM */
err = ar9170_usb_reset(aru);
if (err)
goto err_freehw;
@@ -738,6 +857,8 @@ static void ar9170_usb_disconnect(struct usb_interface *intf)
if (!aru)
return;

+ cancel_work_sync(&aru->reset_work);
+
aru->common.state = AR9170_IDLE;
ar9170_unregister(&aru->common);
ar9170_usb_cancel_urbs(aru);
@@ -759,6 +880,7 @@ static int ar9170_suspend(struct usb_interface *intf,
if (!aru)
return -ENODEV;

+ cancel_work_sync(&aru->reset_work);
aru->common.state = AR9170_IDLE;
ar9170_usb_cancel_urbs(aru);

@@ -776,11 +898,6 @@ static int ar9170_resume(struct usb_interface *intf)
usb_unpoison_anchored_urbs(&aru->rx_submitted);
usb_unpoison_anchored_urbs(&aru->tx_submitted);

- /*
- * FIXME: firmware upload will fail on resume.
- * but this is better than a hang!
- */
-
err = ar9170_usb_init_device(aru);
if (err)
goto err_unrx;
diff --git a/drivers/net/wireless/ath/ar9170/usb.h b/drivers/net/wireless/ath/ar9170/usb.h
index ac42586..d75e6ee 100644
--- a/drivers/net/wireless/ath/ar9170/usb.h
+++ b/drivers/net/wireless/ath/ar9170/usb.h
@@ -51,6 +51,7 @@
#include "ar9170.h"

#define AR9170_NUM_RX_URBS 16
+#define AR9170_NUM_TX_URBS 8

struct firmware;

@@ -60,15 +61,21 @@ struct ar9170_usb {
struct usb_interface *intf;

struct usb_anchor rx_submitted;
+ struct usb_anchor tx_pending;
struct usb_anchor tx_submitted;

- spinlock_t cmdlock;
+ spinlock_t tx_urb_lock;
+ unsigned int tx_submitted_urbs;
+ unsigned int tx_pending_urbs;
+
struct completion cmd_wait;
int readlen;
u8 *readbuf;

const struct firmware *init_values;
const struct firmware *firmware;
+
+ struct work_struct reset_work;
};

#endif /* __USB_H */