drivers: net: usb: pegasus: fix control urb submission
authorPetko Manolov <petkan@nucleusys.com>
Thu, 25 Apr 2013 22:41:50 +0000 (22:41 +0000)
committerDavid S. Miller <davem@davemloft.net>
Mon, 29 Apr 2013 17:57:50 +0000 (13:57 -0400)
Pegasus driver used single callback for sync and async control URBs.
Special flags were employed to distinguish between both, but due to flawed
logic it didn't always work.  As a result of this change
[get|set]_registers() are now much simpler.  Async write is also leaner
and does not use single, statically allocated memory for usb_ctrlrequest,
which is another potential race when asynchronously submitting URBs.

Signed-off-by: Petko Manolov <petkan@nucleusys.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/net/usb/pegasus.c
drivers/net/usb/pegasus.h

index 352b4dc..0969905 100644 (file)
@@ -1,5 +1,5 @@
 /*
- *  Copyright (c) 1999-2005 Petko Manolov (petkan@users.sourceforge.net)
+ *  Copyright (c) 1999-2013 Petko Manolov (petkan@nucleusys.com)
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
@@ -26,6 +26,9 @@
  *             v0.5.1  ethtool support added
  *             v0.5.5  rx socket buffers are in a pool and the their allocation
  *                     is out of the interrupt routine.
+ *             ...
+ *             v0.9.3  simplified [get|set]_register(s), async update registers
+ *                     logic revisited, receive skb_pool removed.
  */
 
 #include <linux/sched.h>
@@ -45,8 +48,8 @@
 /*
  * Version Information
  */
-#define DRIVER_VERSION "v0.6.14 (2006/09/27)"
-#define DRIVER_AUTHOR "Petko Manolov <petkan@users.sourceforge.net>"
+#define DRIVER_VERSION "v0.9.3 (2013/04/25)"
+#define DRIVER_AUTHOR "Petko Manolov <petkan@nucleusys.com>"
 #define DRIVER_DESC "Pegasus/Pegasus II USB Ethernet driver"
 
 static const char driver_name[] = "pegasus";
@@ -108,218 +111,90 @@ MODULE_PARM_DESC(msg_level, "Override default message level");
 MODULE_DEVICE_TABLE(usb, pegasus_ids);
 static const struct net_device_ops pegasus_netdev_ops;
 
-static int update_eth_regs_async(pegasus_t *);
-/* Aargh!!! I _really_ hate such tweaks */
-static void ctrl_callback(struct urb *urb)
+/*****/
+
+static void async_ctrl_callback(struct urb *urb)
 {
-       pegasus_t *pegasus = urb->context;
+       struct usb_ctrlrequest *req = (struct usb_ctrlrequest *)urb->context;
        int status = urb->status;
 
-       if (!pegasus)
-               return;
-
-       switch (status) {
-       case 0:
-               if (pegasus->flags & ETH_REGS_CHANGE) {
-                       pegasus->flags &= ~ETH_REGS_CHANGE;
-                       pegasus->flags |= ETH_REGS_CHANGED;
-                       update_eth_regs_async(pegasus);
-                       return;
-               }
-               break;
-       case -EINPROGRESS:
-               return;
-       case -ENOENT:
-               break;
-       default:
-               if (net_ratelimit())
-                       netif_dbg(pegasus, drv, pegasus->net,
-                                 "%s, status %d\n", __func__, status);
-               break;
-       }
-       pegasus->flags &= ~ETH_REGS_CHANGED;
-       wake_up(&pegasus->ctrl_wait);
+       if (status < 0)
+               dev_dbg(&urb->dev->dev, "%s failed with %d", __func__, status);
+       kfree(req);
+       usb_free_urb(urb);
 }
 
-static int get_registers(pegasus_t *pegasus, __u16 indx, __u16 size,
-                        void *data)
+static int get_registers(pegasus_t *pegasus, __u16 indx, __u16 size, void *data)
 {
        int ret;
-       char *buffer;
-       DECLARE_WAITQUEUE(wait, current);
-
-       buffer = kmalloc(size, GFP_KERNEL);
-       if (!buffer)
-               return -ENOMEM;
-
-       add_wait_queue(&pegasus->ctrl_wait, &wait);
-       set_current_state(TASK_UNINTERRUPTIBLE);
-       while (pegasus->flags & ETH_REGS_CHANGED)
-               schedule();
-       remove_wait_queue(&pegasus->ctrl_wait, &wait);
-       set_current_state(TASK_RUNNING);
-
-       pegasus->dr.bRequestType = PEGASUS_REQT_READ;
-       pegasus->dr.bRequest = PEGASUS_REQ_GET_REGS;
-       pegasus->dr.wValue = cpu_to_le16(0);
-       pegasus->dr.wIndex = cpu_to_le16(indx);
-       pegasus->dr.wLength = cpu_to_le16(size);
-       pegasus->ctrl_urb->transfer_buffer_length = size;
-
-       usb_fill_control_urb(pegasus->ctrl_urb, pegasus->usb,
-                            usb_rcvctrlpipe(pegasus->usb, 0),
-                            (char *) &pegasus->dr,
-                            buffer, size, ctrl_callback, pegasus);
-
-       add_wait_queue(&pegasus->ctrl_wait, &wait);
-       set_current_state(TASK_UNINTERRUPTIBLE);
-
-       /* using ATOMIC, we'd never wake up if we slept */
-       if ((ret = usb_submit_urb(pegasus->ctrl_urb, GFP_ATOMIC))) {
-               set_current_state(TASK_RUNNING);
-               if (ret == -ENODEV)
-                       netif_device_detach(pegasus->net);
-               if (net_ratelimit())
-                       netif_err(pegasus, drv, pegasus->net,
-                                 "%s, status %d\n", __func__, ret);
-               goto out;
-       }
-
-       schedule();
-out:
-       remove_wait_queue(&pegasus->ctrl_wait, &wait);
-       memcpy(data, buffer, size);
-       kfree(buffer);
 
+       ret = usb_control_msg(pegasus->usb, usb_rcvctrlpipe(pegasus->usb, 0),
+                             PEGASUS_REQ_GET_REGS, PEGASUS_REQT_READ, 0,
+                             indx, data, size, 1000);
+       if (ret < 0)
+               netif_dbg(pegasus, drv, pegasus->net,
+                         "%s returned %d\n", __func__, ret);
        return ret;
 }
 
-static int set_registers(pegasus_t *pegasus, __u16 indx, __u16 size,
-                        void *data)
+static int set_registers(pegasus_t *pegasus, __u16 indx, __u16 size, void *data)
 {
        int ret;
-       char *buffer;
-       DECLARE_WAITQUEUE(wait, current);
-
-       buffer = kmemdup(data, size, GFP_KERNEL);
-       if (!buffer) {
-               netif_warn(pegasus, drv, pegasus->net,
-                          "out of memory in %s\n", __func__);
-               return -ENOMEM;
-       }
-
-       add_wait_queue(&pegasus->ctrl_wait, &wait);
-       set_current_state(TASK_UNINTERRUPTIBLE);
-       while (pegasus->flags & ETH_REGS_CHANGED)
-               schedule();
-       remove_wait_queue(&pegasus->ctrl_wait, &wait);
-       set_current_state(TASK_RUNNING);
-
-       pegasus->dr.bRequestType = PEGASUS_REQT_WRITE;
-       pegasus->dr.bRequest = PEGASUS_REQ_SET_REGS;
-       pegasus->dr.wValue = cpu_to_le16(0);
-       pegasus->dr.wIndex = cpu_to_le16(indx);
-       pegasus->dr.wLength = cpu_to_le16(size);
-       pegasus->ctrl_urb->transfer_buffer_length = size;
-
-       usb_fill_control_urb(pegasus->ctrl_urb, pegasus->usb,
-                            usb_sndctrlpipe(pegasus->usb, 0),
-                            (char *) &pegasus->dr,
-                            buffer, size, ctrl_callback, pegasus);
-
-       add_wait_queue(&pegasus->ctrl_wait, &wait);
-       set_current_state(TASK_UNINTERRUPTIBLE);
-
-       if ((ret = usb_submit_urb(pegasus->ctrl_urb, GFP_ATOMIC))) {
-               if (ret == -ENODEV)
-                       netif_device_detach(pegasus->net);
-               netif_err(pegasus, drv, pegasus->net,
-                         "%s, status %d\n", __func__, ret);
-               goto out;
-       }
-
-       schedule();
-out:
-       remove_wait_queue(&pegasus->ctrl_wait, &wait);
-       kfree(buffer);
 
+       ret = usb_control_msg(pegasus->usb, usb_sndctrlpipe(pegasus->usb, 0),
+                             PEGASUS_REQ_SET_REGS, PEGASUS_REQT_WRITE, 0,
+                             indx, data, size, 100);
+       if (ret < 0)
+               netif_dbg(pegasus, drv, pegasus->net,
+                         "%s returned %d\n", __func__, ret);
        return ret;
 }
 
 static int set_register(pegasus_t *pegasus, __u16 indx, __u8 data)
 {
        int ret;
-       char *tmp;
-       DECLARE_WAITQUEUE(wait, current);
-
-       tmp = kmemdup(&data, 1, GFP_KERNEL);
-       if (!tmp) {
-               netif_warn(pegasus, drv, pegasus->net,
-                          "out of memory in %s\n", __func__);
-               return -ENOMEM;
-       }
-       add_wait_queue(&pegasus->ctrl_wait, &wait);
-       set_current_state(TASK_UNINTERRUPTIBLE);
-       while (pegasus->flags & ETH_REGS_CHANGED)
-               schedule();
-       remove_wait_queue(&pegasus->ctrl_wait, &wait);
-       set_current_state(TASK_RUNNING);
-
-       pegasus->dr.bRequestType = PEGASUS_REQT_WRITE;
-       pegasus->dr.bRequest = PEGASUS_REQ_SET_REG;
-       pegasus->dr.wValue = cpu_to_le16(data);
-       pegasus->dr.wIndex = cpu_to_le16(indx);
-       pegasus->dr.wLength = cpu_to_le16(1);
-       pegasus->ctrl_urb->transfer_buffer_length = 1;
-
-       usb_fill_control_urb(pegasus->ctrl_urb, pegasus->usb,
-                            usb_sndctrlpipe(pegasus->usb, 0),
-                            (char *) &pegasus->dr,
-                            tmp, 1, ctrl_callback, pegasus);
-
-       add_wait_queue(&pegasus->ctrl_wait, &wait);
-       set_current_state(TASK_UNINTERRUPTIBLE);
-
-       if ((ret = usb_submit_urb(pegasus->ctrl_urb, GFP_ATOMIC))) {
-               if (ret == -ENODEV)
-                       netif_device_detach(pegasus->net);
-               if (net_ratelimit())
-                       netif_err(pegasus, drv, pegasus->net,
-                                 "%s, status %d\n", __func__, ret);
-               goto out;
-       }
-
-       schedule();
-out:
-       remove_wait_queue(&pegasus->ctrl_wait, &wait);
-       kfree(tmp);
 
+       ret = usb_control_msg(pegasus->usb, usb_sndctrlpipe(pegasus->usb, 0),
+                             PEGASUS_REQ_SET_REG, PEGASUS_REQT_WRITE, data,
+                             indx, &data, 1, 1000);
+       if (ret < 0)
+               netif_dbg(pegasus, drv, pegasus->net,
+                         "%s returned %d\n", __func__, ret);
        return ret;
 }
 
 static int update_eth_regs_async(pegasus_t *pegasus)
 {
-       int ret;
-
-       pegasus->dr.bRequestType = PEGASUS_REQT_WRITE;
-       pegasus->dr.bRequest = PEGASUS_REQ_SET_REGS;
-       pegasus->dr.wValue = cpu_to_le16(0);
-       pegasus->dr.wIndex = cpu_to_le16(EthCtrl0);
-       pegasus->dr.wLength = cpu_to_le16(3);
-       pegasus->ctrl_urb->transfer_buffer_length = 3;
+       int ret = -ENOMEM;
+       struct urb *async_urb;
+       struct usb_ctrlrequest *req;
 
-       usb_fill_control_urb(pegasus->ctrl_urb, pegasus->usb,
-                            usb_sndctrlpipe(pegasus->usb, 0),
-                            (char *) &pegasus->dr,
-                            pegasus->eth_regs, 3, ctrl_callback, pegasus);
+       req = kmalloc(sizeof(struct usb_ctrlrequest), GFP_ATOMIC);
+       if (req == NULL)
+               return ret;
 
-       if ((ret = usb_submit_urb(pegasus->ctrl_urb, GFP_ATOMIC))) {
+       async_urb = usb_alloc_urb(0, GFP_ATOMIC);
+       if (async_urb == NULL) {
+               kfree(req);
+               return ret;
+       }
+       req->bRequestType = PEGASUS_REQT_WRITE;
+       req->bRequest = PEGASUS_REQ_SET_REGS;
+       req->wValue = cpu_to_le16(0);
+       req->wIndex = cpu_to_le16(EthCtrl0);
+       req->wLength = cpu_to_le16(3);
+
+       usb_fill_control_urb(async_urb, pegasus->usb,
+                            usb_sndctrlpipe(pegasus->usb, 0), (void *)req,
+                            pegasus->eth_regs, 3, async_ctrl_callback, req);
+
+       ret = usb_submit_urb(async_urb, GFP_ATOMIC);
+       if (ret) {
                if (ret == -ENODEV)
                        netif_device_detach(pegasus->net);
                netif_err(pegasus, drv, pegasus->net,
-                         "%s, status %d\n", __func__, ret);
+                         "%s returned %d\n", __func__, ret);
        }
-
        return ret;
 }
 
@@ -899,7 +774,6 @@ static void free_all_urbs(pegasus_t *pegasus)
        usb_free_urb(pegasus->intr_urb);
        usb_free_urb(pegasus->tx_urb);
        usb_free_urb(pegasus->rx_urb);
-       usb_free_urb(pegasus->ctrl_urb);
 }
 
 static void unlink_all_urbs(pegasus_t *pegasus)
@@ -907,47 +781,42 @@ static void unlink_all_urbs(pegasus_t *pegasus)
        usb_kill_urb(pegasus->intr_urb);
        usb_kill_urb(pegasus->tx_urb);
        usb_kill_urb(pegasus->rx_urb);
-       usb_kill_urb(pegasus->ctrl_urb);
 }
 
 static int alloc_urbs(pegasus_t *pegasus)
 {
-       pegasus->ctrl_urb = usb_alloc_urb(0, GFP_KERNEL);
-       if (!pegasus->ctrl_urb)
-               return 0;
+       int res = -ENOMEM;
+
        pegasus->rx_urb = usb_alloc_urb(0, GFP_KERNEL);
        if (!pegasus->rx_urb) {
-               usb_free_urb(pegasus->ctrl_urb);
-               return 0;
+               return res;
        }
        pegasus->tx_urb = usb_alloc_urb(0, GFP_KERNEL);
        if (!pegasus->tx_urb) {
                usb_free_urb(pegasus->rx_urb);
-               usb_free_urb(pegasus->ctrl_urb);
-               return 0;
+               return res;
        }
        pegasus->intr_urb = usb_alloc_urb(0, GFP_KERNEL);
        if (!pegasus->intr_urb) {
                usb_free_urb(pegasus->tx_urb);
                usb_free_urb(pegasus->rx_urb);
-               usb_free_urb(pegasus->ctrl_urb);
-               return 0;
+               return res;
        }
 
-       return 1;
+       return 0;
 }
 
 static int pegasus_open(struct net_device *net)
 {
        pegasus_t *pegasus = netdev_priv(net);
-       int res;
+       int res=-ENOMEM;
 
        if (pegasus->rx_skb == NULL)
                pegasus->rx_skb = __netdev_alloc_skb_ip_align(pegasus->net,
                                                              PEGASUS_MTU,
                                                              GFP_KERNEL);
        if (!pegasus->rx_skb)
-               return -ENOMEM;
+               goto exit;
 
        res = set_registers(pegasus, EthID, 6, net->dev_addr);
 
@@ -973,7 +842,8 @@ static int pegasus_open(struct net_device *net)
                usb_kill_urb(pegasus->rx_urb);
                goto exit;
        }
-       if ((res = enable_net_traffic(net, pegasus->usb))) {
+       res = enable_net_traffic(net, pegasus->usb);
+       if (res < 0) {
                netif_dbg(pegasus, ifup, net,
                          "can't enable_net_traffic() - %d\n", res);
                res = -EIO;
@@ -1153,11 +1023,7 @@ static void pegasus_set_multicast(struct net_device *net)
                pegasus->eth_regs[EthCtrl0] &= ~RX_MULTICAST;
                pegasus->eth_regs[EthCtrl2] &= ~RX_PROMISCUOUS;
        }
-
-       pegasus->ctrl_urb->status = 0;
-
-       pegasus->flags |= ETH_REGS_CHANGE;
-       ctrl_callback(pegasus->ctrl_urb);
+       update_eth_regs_async(pegasus);
 }
 
 static __u8 mii_phy_probe(pegasus_t *pegasus)
@@ -1274,9 +1140,9 @@ static int pegasus_probe(struct usb_interface *intf,
 
        pegasus = netdev_priv(net);
        pegasus->dev_index = dev_index;
-       init_waitqueue_head(&pegasus->ctrl_wait);
 
-       if (!alloc_urbs(pegasus)) {
+       res = alloc_urbs(pegasus);
+       if (res < 0) {
                dev_err(&intf->dev, "can't allocate %s\n", "urbs");
                goto out1;
        }
@@ -1326,12 +1192,9 @@ static int pegasus_probe(struct usb_interface *intf,
        if (res)
                goto out3;
        queue_delayed_work(pegasus_workqueue, &pegasus->carrier_check,
-                               CARRIER_CHECK_DELAY);
-
-       dev_info(&intf->dev, "%s, %s, %pM\n",
-                net->name,
-                usb_dev_id[dev_index].name,
-                net->dev_addr);
+                          CARRIER_CHECK_DELAY);
+       dev_info(&intf->dev, "%s, %s, %pM\n", net->name,
+                usb_dev_id[dev_index].name, net->dev_addr);
        return 0;
 
 out3:
index 00d44e3..d156462 100644 (file)
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999-2003 Petko Manolov - Petkan (petkan@users.sourceforge.net)
+ * Copyright (c) 1999-2013 Petko Manolov (petkan@nucleusys.com)
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as published
@@ -33,8 +33,6 @@
 #define        CTRL_URB_SLEEP          0x00000020
 #define        PEGASUS_UNPLUG          0x00000040
 #define        PEGASUS_RX_URB_FAIL     0x00000080
-#define        ETH_REGS_CHANGE         0x40000000
-#define        ETH_REGS_CHANGED        0x80000000
 
 #define        RX_MULTICAST            2
 #define        RX_PROMISCUOUS          4
@@ -95,10 +93,8 @@ typedef struct pegasus {
        int                     intr_interval;
        struct tasklet_struct   rx_tl;
        struct delayed_work     carrier_check;
-       struct urb              *ctrl_urb, *rx_urb, *tx_urb, *intr_urb;
+       struct urb              *rx_urb, *tx_urb, *intr_urb;
        struct sk_buff          *rx_skb;
-       struct usb_ctrlrequest  dr;
-       wait_queue_head_t       ctrl_wait;
        int                     chip;
        unsigned char           intr_buff[8];
        __u8                    tx_buff[PEGASUS_MTU];