1 files changed, 138 insertions, 126 deletions

diff --git a/drivers/net/wimax/i2400m/driver.c b/drivers/net/wimax/i2400m/driver.c
index 96a615fe09d..9c78090e72f 100644
--- a/drivers/net/wimax/i2400m/driver.c
+++ b/drivers/net/wimax/i2400m/driver.c
@@ -69,30 +69,12 @@
 #include <linux/module.h>
 #include <linux/moduleparam.h>
 #include <linux/suspend.h>
+#include <linux/slab.h>
 
 #define D_SUBMODULE driver
 #include "debug-levels.h"
 
 
-int i2400m_idle_mode_disabled;	/* 0 (idle mode enabled) by default */
-module_param_named(idle_mode_disabled, i2400m_idle_mode_disabled, int, 0644);
-MODULE_PARM_DESC(idle_mode_disabled,
-		 "If true, the device will not enable idle mode negotiation "
-		 "with the base station (when connected) to save power.");
-
-int i2400m_rx_reorder_disabled;	/* 0 (rx reorder enabled) by default */
-module_param_named(rx_reorder_disabled, i2400m_rx_reorder_disabled, int, 0644);
-MODULE_PARM_DESC(rx_reorder_disabled,
-		 "If true, RX reordering will be disabled.");
-
-int i2400m_power_save_disabled;	/* 0 (power saving enabled) by default */
-module_param_named(power_save_disabled, i2400m_power_save_disabled, int, 0644);
-MODULE_PARM_DESC(power_save_disabled,
-		 "If true, the driver will not tell the device to enter "
-		 "power saving mode when it reports it is ready for it. "
-		 "False by default (so the device is told to do power "
-		 "saving).");
-
 static char i2400m_debug_params[128];
 module_param_string(debug, i2400m_debug_params, sizeof(i2400m_debug_params),
 		    0644);
@@ -110,54 +92,6 @@ MODULE_PARM_DESC(barkers,
 		 "signal; values are appended to a list--setting one value "
 		 "as zero cleans the existing list and starts a new one.");
 
-static
-struct i2400m_work *__i2400m_work_setup(
-	struct i2400m *i2400m, void (*fn)(struct work_struct *),
-	gfp_t gfp_flags, const void *pl, size_t pl_size)
-{
-	struct i2400m_work *iw;
-
-	iw = kzalloc(sizeof(*iw) + pl_size, gfp_flags);
-	if (iw == NULL)
-		return NULL;
-	iw->i2400m = i2400m_get(i2400m);
-	iw->pl_size = pl_size;
-	memcpy(iw->pl, pl, pl_size);
-	INIT_WORK(&iw->ws, fn);
-	return iw;
-}
-
-
-/*
- * Schedule i2400m's specific work on the system's queue.
- *
- * Used for a few cases where we really need it; otherwise, identical
- * to i2400m_queue_work().
- *
- * Returns < 0 errno code on error, 1 if ok.
- *
- * If it returns zero, something really bad happened, as it means the
- * works struct was already queued, but we have just allocated it, so
- * it should not happen.
- */
-int i2400m_schedule_work(struct i2400m *i2400m,
-			 void (*fn)(struct work_struct *), gfp_t gfp_flags,
-			 const void *pl, size_t pl_size)
-{
-	int result;
-	struct i2400m_work *iw;
-
-	result = -ENOMEM;
-	iw = __i2400m_work_setup(i2400m, fn, gfp_flags, pl, pl_size);
-	if (iw != NULL) {
-		result = schedule_work(&iw->ws);
-		if (WARN_ON(result == 0))
-			result = -ENXIO;
-	}
-	return result;
-}
-
-
 /*
  * WiMAX stack operation: relay a message from user space
  *
@@ -288,7 +222,6 @@ int i2400m_check_mac_addr(struct i2400m *i2400m)
 	struct sk_buff *skb;
 	const struct i2400m_tlv_detailed_device_info *ddi;
 	struct net_device *net_dev = i2400m->wimax_dev.net_dev;
-	const unsigned char zeromac[ETH_ALEN] = { 0 };
 
 	d_fnstart(3, dev, "(i2400m %p)\n", i2400m);
 	skb = i2400m_get_device_info(i2400m);
@@ -298,28 +231,19 @@ int i2400m_check_mac_addr(struct i2400m *i2400m)
 			result);
 		goto error;
 	}
-	/* Extract MAC addresss */
+	/* Extract MAC address */
 	ddi = (void *) skb->data;
 	BUILD_BUG_ON(ETH_ALEN != sizeof(ddi->mac_address));
-	d_printf(2, dev, "GET DEVICE INFO: mac addr "
-		 "%02x:%02x:%02x:%02x:%02x:%02x\n",
-		 ddi->mac_address[0], ddi->mac_address[1],
-		 ddi->mac_address[2], ddi->mac_address[3],
-		 ddi->mac_address[4], ddi->mac_address[5]);
+	d_printf(2, dev, "GET DEVICE INFO: mac addr %pM\n",
+		 ddi->mac_address);
 	if (!memcmp(net_dev->perm_addr, ddi->mac_address,
 		   sizeof(ddi->mac_address)))
 		goto ok;
 	dev_warn(dev, "warning: device reports a different MAC address "
 		 "to that of boot mode's\n");
-	dev_warn(dev, "device reports     %02x:%02x:%02x:%02x:%02x:%02x\n",
-		 ddi->mac_address[0], ddi->mac_address[1],
-		 ddi->mac_address[2], ddi->mac_address[3],
-		 ddi->mac_address[4], ddi->mac_address[5]);
-	dev_warn(dev, "boot mode reported %02x:%02x:%02x:%02x:%02x:%02x\n",
-		 net_dev->perm_addr[0], net_dev->perm_addr[1],
-		 net_dev->perm_addr[2], net_dev->perm_addr[3],
-		 net_dev->perm_addr[4], net_dev->perm_addr[5]);
-	if (!memcmp(zeromac, ddi->mac_address, sizeof(zeromac)))
+	dev_warn(dev, "device reports     %pM\n", ddi->mac_address);
+	dev_warn(dev, "boot mode reported %pM\n", net_dev->perm_addr);
+	if (is_zero_ether_addr(ddi->mac_address))
 		dev_err(dev, "device reports an invalid MAC address, "
 			"not updating\n");
 	else {
@@ -403,6 +327,16 @@ retry:
 	result = i2400m_dev_initialize(i2400m);
 	if (result < 0)
 		goto error_dev_initialize;
+
+	/* We don't want any additional unwanted error recovery triggered
+	 * from any other context so if anything went wrong before we come
+	 * here, let's keep i2400m->error_recovery untouched and leave it to
+	 * dev_reset_handle(). See dev_reset_handle(). */
+
+	atomic_dec(&i2400m->error_recovery);
+	/* Every thing works so far, ok, now we are ready to
+	 * take error recovery if it's required. */
+
 	/* At this point, reports will come for the device and set it
 	 * to the right state if it is different than UNINITIALIZED */
 	d_fnend(3, dev, "(net_dev %p [i2400m %p]) = %d\n",
@@ -411,10 +345,10 @@ retry:
 
 error_dev_initialize:
 error_check_mac_addr:
+error_fw_check:
 	i2400m->ready = 0;
 	wmb();		/* see i2400m->ready's documentation  */
 	flush_workqueue(i2400m->work_queue);
-error_fw_check:
 	if (i2400m->bus_dev_stop)
 		i2400m->bus_dev_stop(i2400m);
 error_bus_dev_start:
@@ -444,7 +378,8 @@ int i2400m_dev_start(struct i2400m *i2400m, enum i2400m_bri bm_flags)
 		result = __i2400m_dev_start(i2400m, bm_flags);
 		if (result >= 0) {
 			i2400m->updown = 1;
-			wmb();	/* see i2400m->updown's documentation */
+			i2400m->alive = 1;
+			wmb();/* see i2400m->updown and i2400m->alive's doc */
 		}
 	}
 	mutex_unlock(&i2400m->init_mutex);
@@ -505,7 +440,8 @@ void i2400m_dev_stop(struct i2400m *i2400m)
 	if (i2400m->updown) {
 		__i2400m_dev_stop(i2400m);
 		i2400m->updown = 0;
-		wmb();	/* see i2400m->updown's documentation  */
+		i2400m->alive = 0;
+		wmb();	/* see i2400m->updown and i2400m->alive's doc */
 	}
 	mutex_unlock(&i2400m->init_mutex);
 }
@@ -564,26 +500,23 @@ int i2400m_pm_notifier(struct notifier_block *notifier,
  */
 int i2400m_pre_reset(struct i2400m *i2400m)
 {
-	int result;
 	struct device *dev = i2400m_dev(i2400m);
 
 	d_fnstart(3, dev, "(i2400m %p)\n", i2400m);
 	d_printf(1, dev, "pre-reset shut down\n");
 
-	result = 0;
 	mutex_lock(&i2400m->init_mutex);
 	if (i2400m->updown) {
 		netif_tx_disable(i2400m->wimax_dev.net_dev);
 		__i2400m_dev_stop(i2400m);
-		result = 0;
 		/* down't set updown to zero -- this way
 		 * post_reset can restore properly */
 	}
 	mutex_unlock(&i2400m->init_mutex);
 	if (i2400m->bus_release)
 		i2400m->bus_release(i2400m);
-	d_fnend(3, dev, "(i2400m %p) = %d\n", i2400m, result);
-	return result;
+	d_fnend(3, dev, "(i2400m %p) = 0\n", i2400m);
+	return 0;
 }
 EXPORT_SYMBOL_GPL(i2400m_pre_reset);
 
@@ -625,12 +558,12 @@ int i2400m_post_reset(struct i2400m *i2400m)
 error_dev_start:
 	if (i2400m->bus_release)
 		i2400m->bus_release(i2400m);
-error_bus_setup:
 	/* even if the device was up, it could not be recovered, so we
 	 * mark it as down. */
 	i2400m->updown = 0;
 	wmb();		/* see i2400m->updown's documentation  */
 	mutex_unlock(&i2400m->init_mutex);
+error_bus_setup:
 	d_fnend(3, dev, "(i2400m %p) = %d\n", i2400m, result);
 	return result;
 }
@@ -663,20 +596,17 @@ EXPORT_SYMBOL_GPL(i2400m_post_reset);
 static
 void __i2400m_dev_reset_handle(struct work_struct *ws)
 {
-	int result;
-	struct i2400m_work *iw = container_of(ws, struct i2400m_work, ws);
-	const char *reason;
-	struct i2400m *i2400m = iw->i2400m;
+	struct i2400m *i2400m = container_of(ws, struct i2400m, reset_ws);
+	const char *reason = i2400m->reset_reason;
 	struct device *dev = i2400m_dev(i2400m);
 	struct i2400m_reset_ctx *ctx = i2400m->reset_ctx;
-
-	if (WARN_ON(iw->pl_size != sizeof(reason)))
-		reason = "SW BUG: reason n/a";
-	else
-		memcpy(&reason, iw->pl, sizeof(reason));
+	int result;
 
 	d_fnstart(3, dev, "(ws %p i2400m %p reason %s)\n", ws, i2400m, reason);
 
+	i2400m->boot_mode = 1;
+	wmb();		/* Make sure i2400m_msg_to_dev() sees boot_mode */
+
 	result = 0;
 	if (mutex_trylock(&i2400m->init_mutex) == 0) {
 		/* We are still in i2400m_dev_start() [let it fail] or
@@ -687,39 +617,66 @@ void __i2400m_dev_reset_handle(struct work_struct *ws)
 		complete(&i2400m->msg_completion);
 		goto out;
 	}
-	if (i2400m->updown == 0)  {
-		dev_info(dev, "%s: device is down, doing nothing\n", reason);
-		goto out_unlock;
-	}
+
 	dev_err(dev, "%s: reinitializing driver\n", reason);
-	__i2400m_dev_stop(i2400m);
-	result = __i2400m_dev_start(i2400m,
-				    I2400M_BRI_SOFT | I2400M_BRI_MAC_REINIT);
-	if (result < 0) {
+	rmb();
+	if (i2400m->updown) {
+		__i2400m_dev_stop(i2400m);
 		i2400m->updown = 0;
 		wmb();		/* see i2400m->updown's documentation  */
-		dev_err(dev, "%s: cannot start the device: %d\n",
-			reason, result);
-		result = -EUCLEAN;
 	}
-out_unlock:
+
+	if (i2400m->alive) {
+		result = __i2400m_dev_start(i2400m,
+				    I2400M_BRI_SOFT | I2400M_BRI_MAC_REINIT);
+		if (result < 0) {
+			dev_err(dev, "%s: cannot start the device: %d\n",
+				reason, result);
+			result = -EUCLEAN;
+			if (atomic_read(&i2400m->bus_reset_retries)
+					>= I2400M_BUS_RESET_RETRIES) {
+				result = -ENODEV;
+				dev_err(dev, "tried too many times to "
+					"reset the device, giving up\n");
+			}
+		}
+	}
+
 	if (i2400m->reset_ctx) {
 		ctx->result = result;
 		complete(&ctx->completion);
 	}
 	mutex_unlock(&i2400m->init_mutex);
 	if (result == -EUCLEAN) {
+		/*
+		 * We come here because the reset during operational mode
+		 * wasn't successfully done and need to proceed to a bus
+		 * reset. For the dev_reset_handle() to be able to handle
+		 * the reset event later properly, we restore boot_mode back
+		 * to the state before previous reset. ie: just like we are
+		 * issuing the bus reset for the first time
+		 */
+		i2400m->boot_mode = 0;
+		wmb();
+
+		atomic_inc(&i2400m->bus_reset_retries);
 		/* ops, need to clean up [w/ init_mutex not held] */
 		result = i2400m_reset(i2400m, I2400M_RT_BUS);
 		if (result >= 0)
 			result = -ENODEV;
+	} else {
+		rmb();
+		if (i2400m->alive) {
+			/* great, we expect the device state up and
+			 * dev_start() actually brings the device state up */
+			i2400m->updown = 1;
+			wmb();
+			atomic_set(&i2400m->bus_reset_retries, 0);
+		}
 	}
 out:
-	i2400m_put(i2400m);
-	kfree(iw);
 	d_fnend(3, dev, "(ws %p i2400m %p reason %s) = void\n",
 		ws, i2400m, reason);
-	return;
 }
 
 
@@ -737,19 +694,63 @@ out:
  */
 int i2400m_dev_reset_handle(struct i2400m *i2400m, const char *reason)
 {
-	i2400m->boot_mode = 1;
-	wmb();		/* Make sure i2400m_msg_to_dev() sees boot_mode */
-	return i2400m_schedule_work(i2400m, __i2400m_dev_reset_handle,
-				    GFP_ATOMIC, &reason, sizeof(reason));
+	i2400m->reset_reason = reason;
+	return schedule_work(&i2400m->reset_ws);
 }
 EXPORT_SYMBOL_GPL(i2400m_dev_reset_handle);
 
 
+ /*
+ * The actual work of error recovery.
+ *
+ * The current implementation of error recovery is to trigger a bus reset.
+ */
+static
+void __i2400m_error_recovery(struct work_struct *ws)
+{
+	struct i2400m *i2400m = container_of(ws, struct i2400m, recovery_ws);
+
+	i2400m_reset(i2400m, I2400M_RT_BUS);
+}
+
+/*
+ * Schedule a work struct for error recovery.
+ *
+ * The intention of error recovery is to bring back the device to some
+ * known state whenever TX sees -110 (-ETIMEOUT) on copying the data to
+ * the device. The TX failure could mean a device bus stuck, so the current
+ * error recovery implementation is to trigger a bus reset to the device
+ * and hopefully it can bring back the device.
+ *
+ * The actual work of error recovery has to be in a thread context because
+ * it is kicked off in the TX thread (i2400ms->tx_workqueue) which is to be
+ * destroyed by the error recovery mechanism (currently a bus reset).
+ *
+ * Also, there may be already a queue of TX works that all hit
+ * the -ETIMEOUT error condition because the device is stuck already.
+ * Since bus reset is used as the error recovery mechanism and we don't
+ * want consecutive bus resets simply because the multiple TX works
+ * in the queue all hit the same device erratum, the flag "error_recovery"
+ * is introduced for preventing unwanted consecutive bus resets.
+ *
+ * Error recovery shall only be invoked again if previous one was completed.
+ * The flag error_recovery is set when error recovery mechanism is scheduled,
+ * and is checked when we need to schedule another error recovery. If it is
+ * in place already, then we shouldn't schedule another one.
+ */
+void i2400m_error_recovery(struct i2400m *i2400m)
+{
+	if (atomic_add_return(1, &i2400m->error_recovery) == 1)
+		schedule_work(&i2400m->recovery_ws);
+	else
+		atomic_dec(&i2400m->error_recovery);
+}
+EXPORT_SYMBOL_GPL(i2400m_error_recovery);
+
 /*
  * Alloc the command and ack buffers for boot mode
  *
- * Get the buffers needed to deal with boot mode messages.  These
- * buffers need to be allocated before the sdio recieve irq is setup.
+ * Get the buffers needed to deal with boot mode messages.
  */
 static
 int i2400m_bm_buf_alloc(struct i2400m *i2400m)
@@ -811,6 +812,17 @@ void i2400m_init(struct i2400m *i2400m)
 
 	mutex_init(&i2400m->init_mutex);
 	/* wake_tx_ws is initialized in i2400m_tx_setup() */
+
+	INIT_WORK(&i2400m->reset_ws, __i2400m_dev_reset_handle);
+	INIT_WORK(&i2400m->recovery_ws, __i2400m_error_recovery);
+
+	atomic_set(&i2400m->bus_reset_retries, 0);
+
+	i2400m->alive = 0;
+
+	/* initialize error_recovery to 1 for denoting we
+	 * are not yet ready to take any error recovery */
+	atomic_set(&i2400m->error_recovery, 1);
 }
 EXPORT_SYMBOL_GPL(i2400m_init);
 
@@ -880,7 +892,7 @@ int i2400m_setup(struct i2400m *i2400m, enum i2400m_bri bm_flags)
 	result = i2400m_read_mac_addr(i2400m);
 	if (result < 0)
 		goto error_read_mac_addr;
-	random_ether_addr(i2400m->src_mac_addr);
+	eth_random_addr(i2400m->src_mac_addr);
 
 	i2400m->pm_notifier.notifier_call = i2400m_pm_notifier;
 	register_pm_notifier(&i2400m->pm_notifier);
@@ -958,6 +970,9 @@ void i2400m_release(struct i2400m *i2400m)
 
 	i2400m_dev_stop(i2400m);
 
+	cancel_work_sync(&i2400m->reset_ws);
+	cancel_work_sync(&i2400m->recovery_ws);
+
 	i2400m_debugfs_rm(i2400m);
 	sysfs_remove_group(&i2400m->wimax_dev.net_dev->dev.kobj,
 			   &i2400m_dev_attr_group);
@@ -1001,10 +1016,7 @@ module_init(i2400m_driver_init);
 static
 void __exit i2400m_driver_exit(void)
 {
-	/* for scheds i2400m_dev_reset_handle() */
-	flush_scheduled_work();
 	i2400m_barker_db_exit();
-	return;
 }
 module_exit(i2400m_driver_exit);