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path: root/drivers/net/wimax/i2400m/driver.c
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Diffstat (limited to 'drivers/net/wimax/i2400m/driver.c')
-rw-r--r--drivers/net/wimax/i2400m/driver.c167
1 files changed, 128 insertions, 39 deletions
diff --git a/drivers/net/wimax/i2400m/driver.c b/drivers/net/wimax/i2400m/driver.c
index 94dc83c..9c8b78d 100644
--- a/drivers/net/wimax/i2400m/driver.c
+++ b/drivers/net/wimax/i2400m/driver.c
@@ -75,25 +75,6 @@
#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);
@@ -395,6 +376,16 @@ 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",
@@ -403,10 +394,10 @@ 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:
@@ -436,7 +427,8 @@ 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);
@@ -497,7 +489,8 @@ 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);
}
@@ -617,12 +610,12 @@ 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;
}
@@ -669,6 +662,9 @@ void __i2400m_dev_reset_handle(struct work_struct *ws)
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
@@ -679,39 +675,68 @@ 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 successully 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;
}
@@ -729,14 +754,72 @@ 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));
}
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_work *iw = container_of(ws, struct i2400m_work, ws);
+ struct i2400m *i2400m = iw->i2400m;
+
+ i2400m_reset(i2400m, I2400M_RT_BUS);
+
+ i2400m_put(i2400m);
+ kfree(iw);
+ return;
+}
+
+/*
+ * 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)
+{
+ struct device *dev = i2400m_dev(i2400m);
+
+ if (atomic_add_return(1, &i2400m->error_recovery) == 1) {
+ if (i2400m_schedule_work(i2400m, __i2400m_error_recovery,
+ GFP_ATOMIC, NULL, 0) < 0) {
+ dev_err(dev, "run out of memory for "
+ "scheduling an error recovery ?\n");
+ atomic_dec(&i2400m->error_recovery);
+ }
+ } else
+ atomic_dec(&i2400m->error_recovery);
+ return;
+}
+EXPORT_SYMBOL_GPL(i2400m_error_recovery);
+
/*
* Alloc the command and ack buffers for boot mode
*
@@ -803,6 +886,13 @@ void i2400m_init(struct i2400m *i2400m)
mutex_init(&i2400m->init_mutex);
/* wake_tx_ws is initialized in i2400m_tx_setup() */
+ 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);
@@ -996,7 +1086,6 @@ 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);