diff options
Diffstat (limited to 'kernel/drivers/net/wimax/i2400m/driver.c')
| -rw-r--r-- | kernel/drivers/net/wimax/i2400m/driver.c | 1025 |
1 files changed, 1025 insertions, 0 deletions
diff --git a/kernel/drivers/net/wimax/i2400m/driver.c b/kernel/drivers/net/wimax/i2400m/driver.c new file mode 100644 index 000000000..9c78090e7 --- /dev/null +++ b/kernel/drivers/net/wimax/i2400m/driver.c @@ -0,0 +1,1025 @@ +/* + * Intel Wireless WiMAX Connection 2400m + * Generic probe/disconnect, reset and message passing + * + * + * Copyright (C) 2007-2008 Intel Corporation <linux-wimax@intel.com> + * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.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 by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA + * 02110-1301, USA. + * + * + * See i2400m.h for driver documentation. This contains helpers for + * the driver model glue [_setup()/_release()], handling device resets + * [_dev_reset_handle()], and the backends for the WiMAX stack ops + * reset [_op_reset()] and message from user [_op_msg_from_user()]. + * + * ROADMAP: + * + * i2400m_op_msg_from_user() + * i2400m_msg_to_dev() + * wimax_msg_to_user_send() + * + * i2400m_op_reset() + * i240m->bus_reset() + * + * i2400m_dev_reset_handle() + * __i2400m_dev_reset_handle() + * __i2400m_dev_stop() + * __i2400m_dev_start() + * + * i2400m_setup() + * i2400m->bus_setup() + * i2400m_bootrom_init() + * register_netdev() + * wimax_dev_add() + * i2400m_dev_start() + * __i2400m_dev_start() + * i2400m_dev_bootstrap() + * i2400m_tx_setup() + * i2400m->bus_dev_start() + * i2400m_firmware_check() + * i2400m_check_mac_addr() + * + * i2400m_release() + * i2400m_dev_stop() + * __i2400m_dev_stop() + * i2400m_dev_shutdown() + * i2400m->bus_dev_stop() + * i2400m_tx_release() + * i2400m->bus_release() + * wimax_dev_rm() + * unregister_netdev() + */ +#include "i2400m.h" +#include <linux/etherdevice.h> +#include <linux/wimax/i2400m.h> +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/suspend.h> +#include <linux/slab.h> + +#define D_SUBMODULE driver +#include "debug-levels.h" + + +static char i2400m_debug_params[128]; +module_param_string(debug, i2400m_debug_params, sizeof(i2400m_debug_params), + 0644); +MODULE_PARM_DESC(debug, + "String of space-separated NAME:VALUE pairs, where NAMEs " + "are the different debug submodules and VALUE are the " + "initial debug value to set."); + +static char i2400m_barkers_params[128]; +module_param_string(barkers, i2400m_barkers_params, + sizeof(i2400m_barkers_params), 0644); +MODULE_PARM_DESC(barkers, + "String of comma-separated 32-bit values; each is " + "recognized as the value the device sends as a reboot " + "signal; values are appended to a list--setting one value " + "as zero cleans the existing list and starts a new one."); + +/* + * WiMAX stack operation: relay a message from user space + * + * @wimax_dev: device descriptor + * @pipe_name: named pipe the message is for + * @msg_buf: pointer to the message bytes + * @msg_len: length of the buffer + * @genl_info: passed by the generic netlink layer + * + * The WiMAX stack will call this function when a message was received + * from user space. + * + * For the i2400m, this is an L3L4 message, as specified in + * include/linux/wimax/i2400m.h, and thus prefixed with a 'struct + * i2400m_l3l4_hdr'. Driver (and device) expect the messages to be + * coded in Little Endian. + * + * This function just verifies that the header declaration and the + * payload are consistent and then deals with it, either forwarding it + * to the device or procesing it locally. + * + * In the i2400m, messages are basically commands that will carry an + * ack, so we use i2400m_msg_to_dev() and then deliver the ack back to + * user space. The rx.c code might intercept the response and use it + * to update the driver's state, but then it will pass it on so it can + * be relayed back to user space. + * + * Note that asynchronous events from the device are processed and + * sent to user space in rx.c. + */ +static +int i2400m_op_msg_from_user(struct wimax_dev *wimax_dev, + const char *pipe_name, + const void *msg_buf, size_t msg_len, + const struct genl_info *genl_info) +{ + int result; + struct i2400m *i2400m = wimax_dev_to_i2400m(wimax_dev); + struct device *dev = i2400m_dev(i2400m); + struct sk_buff *ack_skb; + + d_fnstart(4, dev, "(wimax_dev %p [i2400m %p] msg_buf %p " + "msg_len %zu genl_info %p)\n", wimax_dev, i2400m, + msg_buf, msg_len, genl_info); + ack_skb = i2400m_msg_to_dev(i2400m, msg_buf, msg_len); + result = PTR_ERR(ack_skb); + if (IS_ERR(ack_skb)) + goto error_msg_to_dev; + result = wimax_msg_send(&i2400m->wimax_dev, ack_skb); +error_msg_to_dev: + d_fnend(4, dev, "(wimax_dev %p [i2400m %p] msg_buf %p msg_len %zu " + "genl_info %p) = %d\n", wimax_dev, i2400m, msg_buf, msg_len, + genl_info, result); + return result; +} + + +/* + * Context to wait for a reset to finalize + */ +struct i2400m_reset_ctx { + struct completion completion; + int result; +}; + + +/* + * WiMAX stack operation: reset a device + * + * @wimax_dev: device descriptor + * + * See the documentation for wimax_reset() and wimax_dev->op_reset for + * the requirements of this function. The WiMAX stack guarantees + * serialization on calls to this function. + * + * Do a warm reset on the device; if it fails, resort to a cold reset + * and return -ENODEV. On successful warm reset, we need to block + * until it is complete. + * + * The bus-driver implementation of reset takes care of falling back + * to cold reset if warm fails. + */ +static +int i2400m_op_reset(struct wimax_dev *wimax_dev) +{ + int result; + struct i2400m *i2400m = wimax_dev_to_i2400m(wimax_dev); + struct device *dev = i2400m_dev(i2400m); + struct i2400m_reset_ctx ctx = { + .completion = COMPLETION_INITIALIZER_ONSTACK(ctx.completion), + .result = 0, + }; + + d_fnstart(4, dev, "(wimax_dev %p)\n", wimax_dev); + mutex_lock(&i2400m->init_mutex); + i2400m->reset_ctx = &ctx; + mutex_unlock(&i2400m->init_mutex); + result = i2400m_reset(i2400m, I2400M_RT_WARM); + if (result < 0) + goto out; + result = wait_for_completion_timeout(&ctx.completion, 4*HZ); + if (result == 0) + result = -ETIMEDOUT; + else if (result > 0) + result = ctx.result; + /* if result < 0, pass it on */ + mutex_lock(&i2400m->init_mutex); + i2400m->reset_ctx = NULL; + mutex_unlock(&i2400m->init_mutex); +out: + d_fnend(4, dev, "(wimax_dev %p) = %d\n", wimax_dev, result); + return result; +} + + +/* + * Check the MAC address we got from boot mode is ok + * + * @i2400m: device descriptor + * + * Returns: 0 if ok, < 0 errno code on error. + */ +static +int i2400m_check_mac_addr(struct i2400m *i2400m) +{ + int result; + struct device *dev = i2400m_dev(i2400m); + struct sk_buff *skb; + const struct i2400m_tlv_detailed_device_info *ddi; + struct net_device *net_dev = i2400m->wimax_dev.net_dev; + + d_fnstart(3, dev, "(i2400m %p)\n", i2400m); + skb = i2400m_get_device_info(i2400m); + if (IS_ERR(skb)) { + result = PTR_ERR(skb); + dev_err(dev, "Cannot verify MAC address, error reading: %d\n", + result); + goto error; + } + /* 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 %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 %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 { + dev_warn(dev, "updating MAC address\n"); + net_dev->addr_len = ETH_ALEN; + memcpy(net_dev->perm_addr, ddi->mac_address, ETH_ALEN); + memcpy(net_dev->dev_addr, ddi->mac_address, ETH_ALEN); + } +ok: + result = 0; + kfree_skb(skb); +error: + d_fnend(3, dev, "(i2400m %p) = %d\n", i2400m, result); + return result; +} + + +/** + * __i2400m_dev_start - Bring up driver communication with the device + * + * @i2400m: device descriptor + * @flags: boot mode flags + * + * Returns: 0 if ok, < 0 errno code on error. + * + * Uploads firmware and brings up all the resources needed to be able + * to communicate with the device. + * + * The workqueue has to be setup early, at least before RX handling + * (it's only real user for now) so it can process reports as they + * arrive. We also want to destroy it if we retry, to make sure it is + * flushed...easier like this. + * + * TX needs to be setup before the bus-specific code (otherwise on + * shutdown, the bus-tx code could try to access it). + */ +static +int __i2400m_dev_start(struct i2400m *i2400m, enum i2400m_bri flags) +{ + int result; + struct wimax_dev *wimax_dev = &i2400m->wimax_dev; + struct net_device *net_dev = wimax_dev->net_dev; + struct device *dev = i2400m_dev(i2400m); + int times = i2400m->bus_bm_retries; + + d_fnstart(3, dev, "(i2400m %p)\n", i2400m); +retry: + result = i2400m_dev_bootstrap(i2400m, flags); + if (result < 0) { + dev_err(dev, "cannot bootstrap device: %d\n", result); + goto error_bootstrap; + } + result = i2400m_tx_setup(i2400m); + if (result < 0) + goto error_tx_setup; + result = i2400m_rx_setup(i2400m); + if (result < 0) + goto error_rx_setup; + i2400m->work_queue = create_singlethread_workqueue(wimax_dev->name); + if (i2400m->work_queue == NULL) { + result = -ENOMEM; + dev_err(dev, "cannot create workqueue\n"); + goto error_create_workqueue; + } + if (i2400m->bus_dev_start) { + result = i2400m->bus_dev_start(i2400m); + if (result < 0) + goto error_bus_dev_start; + } + i2400m->ready = 1; + wmb(); /* see i2400m->ready's documentation */ + /* process pending reports from the device */ + queue_work(i2400m->work_queue, &i2400m->rx_report_ws); + result = i2400m_firmware_check(i2400m); /* fw versions ok? */ + if (result < 0) + goto error_fw_check; + /* At this point is ok to send commands to the device */ + result = i2400m_check_mac_addr(i2400m); + if (result < 0) + goto error_check_mac_addr; + 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", + net_dev, i2400m, result); + return result; + +error_dev_initialize: +error_check_mac_addr: +error_fw_check: + i2400m->ready = 0; + wmb(); /* see i2400m->ready's documentation */ + flush_workqueue(i2400m->work_queue); + if (i2400m->bus_dev_stop) + i2400m->bus_dev_stop(i2400m); +error_bus_dev_start: + destroy_workqueue(i2400m->work_queue); +error_create_workqueue: + i2400m_rx_release(i2400m); +error_rx_setup: + i2400m_tx_release(i2400m); +error_tx_setup: +error_bootstrap: + if (result == -EL3RST && times-- > 0) { + flags = I2400M_BRI_SOFT|I2400M_BRI_MAC_REINIT; + goto retry; + } + d_fnend(3, dev, "(net_dev %p [i2400m %p]) = %d\n", + net_dev, i2400m, result); + return result; +} + + +static +int i2400m_dev_start(struct i2400m *i2400m, enum i2400m_bri bm_flags) +{ + int result = 0; + mutex_lock(&i2400m->init_mutex); /* Well, start the device */ + if (i2400m->updown == 0) { + result = __i2400m_dev_start(i2400m, bm_flags); + if (result >= 0) { + i2400m->updown = 1; + i2400m->alive = 1; + wmb();/* see i2400m->updown and i2400m->alive's doc */ + } + } + mutex_unlock(&i2400m->init_mutex); + return result; +} + + +/** + * i2400m_dev_stop - Tear down driver communication with the device + * + * @i2400m: device descriptor + * + * Returns: 0 if ok, < 0 errno code on error. + * + * Releases all the resources allocated to communicate with the + * device. Note we cannot destroy the workqueue earlier as until RX is + * fully destroyed, it could still try to schedule jobs. + */ +static +void __i2400m_dev_stop(struct i2400m *i2400m) +{ + struct wimax_dev *wimax_dev = &i2400m->wimax_dev; + struct device *dev = i2400m_dev(i2400m); + + d_fnstart(3, dev, "(i2400m %p)\n", i2400m); + wimax_state_change(wimax_dev, __WIMAX_ST_QUIESCING); + i2400m_msg_to_dev_cancel_wait(i2400m, -EL3RST); + complete(&i2400m->msg_completion); + i2400m_net_wake_stop(i2400m); + i2400m_dev_shutdown(i2400m); + /* + * Make sure no report hooks are running *before* we stop the + * communication infrastructure with the device. + */ + i2400m->ready = 0; /* nobody can queue work anymore */ + wmb(); /* see i2400m->ready's documentation */ + flush_workqueue(i2400m->work_queue); + + if (i2400m->bus_dev_stop) + i2400m->bus_dev_stop(i2400m); + destroy_workqueue(i2400m->work_queue); + i2400m_rx_release(i2400m); + i2400m_tx_release(i2400m); + wimax_state_change(wimax_dev, WIMAX_ST_DOWN); + d_fnend(3, dev, "(i2400m %p) = 0\n", i2400m); +} + + +/* + * Watch out -- we only need to stop if there is a need for it. The + * device could have reset itself and failed to come up again (see + * _i2400m_dev_reset_handle()). + */ +static +void i2400m_dev_stop(struct i2400m *i2400m) +{ + mutex_lock(&i2400m->init_mutex); + if (i2400m->updown) { + __i2400m_dev_stop(i2400m); + i2400m->updown = 0; + i2400m->alive = 0; + wmb(); /* see i2400m->updown and i2400m->alive's doc */ + } + mutex_unlock(&i2400m->init_mutex); +} + + +/* + * Listen to PM events to cache the firmware before suspend/hibernation + * + * When the device comes out of suspend, it might go into reset and + * firmware has to be uploaded again. At resume, most of the times, we + * can't load firmware images from disk, so we need to cache it. + * + * i2400m_fw_cache() will allocate a kobject and attach the firmware + * to it; that way we don't have to worry too much about the fw loader + * hitting a race condition. + * + * Note: modus operandi stolen from the Orinoco driver; thx. + */ +static +int i2400m_pm_notifier(struct notifier_block *notifier, + unsigned long pm_event, + void *unused) +{ + struct i2400m *i2400m = + container_of(notifier, struct i2400m, pm_notifier); + struct device *dev = i2400m_dev(i2400m); + + d_fnstart(3, dev, "(i2400m %p pm_event %lx)\n", i2400m, pm_event); + switch (pm_event) { + case PM_HIBERNATION_PREPARE: + case PM_SUSPEND_PREPARE: + i2400m_fw_cache(i2400m); + break; + case PM_POST_RESTORE: + /* Restore from hibernation failed. We need to clean + * up in exactly the same way, so fall through. */ + case PM_POST_HIBERNATION: + case PM_POST_SUSPEND: + i2400m_fw_uncache(i2400m); + break; + + case PM_RESTORE_PREPARE: + default: + break; + } + d_fnend(3, dev, "(i2400m %p pm_event %lx) = void\n", i2400m, pm_event); + return NOTIFY_DONE; +} + + +/* + * pre-reset is called before a device is going on reset + * + * This has to be followed by a call to i2400m_post_reset(), otherwise + * bad things might happen. + */ +int i2400m_pre_reset(struct i2400m *i2400m) +{ + struct device *dev = i2400m_dev(i2400m); + + d_fnstart(3, dev, "(i2400m %p)\n", i2400m); + d_printf(1, dev, "pre-reset shut down\n"); + + mutex_lock(&i2400m->init_mutex); + if (i2400m->updown) { + netif_tx_disable(i2400m->wimax_dev.net_dev); + __i2400m_dev_stop(i2400m); + /* 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) = 0\n", i2400m); + return 0; +} +EXPORT_SYMBOL_GPL(i2400m_pre_reset); + + +/* + * Restore device state after a reset + * + * Do the work needed after a device reset to bring it up to the same + * state as it was before the reset. + * + * NOTE: this requires i2400m->init_mutex taken + */ +int i2400m_post_reset(struct i2400m *i2400m) +{ + int result = 0; + struct device *dev = i2400m_dev(i2400m); + + d_fnstart(3, dev, "(i2400m %p)\n", i2400m); + d_printf(1, dev, "post-reset start\n"); + if (i2400m->bus_setup) { + result = i2400m->bus_setup(i2400m); + if (result < 0) { + dev_err(dev, "bus-specific setup failed: %d\n", + result); + goto error_bus_setup; + } + } + mutex_lock(&i2400m->init_mutex); + if (i2400m->updown) { + result = __i2400m_dev_start( + i2400m, I2400M_BRI_SOFT | I2400M_BRI_MAC_REINIT); + if (result < 0) + goto error_dev_start; + } + mutex_unlock(&i2400m->init_mutex); + d_fnend(3, dev, "(i2400m %p) = %d\n", i2400m, result); + return result; + +error_dev_start: + if (i2400m->bus_release) + i2400m->bus_release(i2400m); + /* 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; +} +EXPORT_SYMBOL_GPL(i2400m_post_reset); + + +/* + * The device has rebooted; fix up the device and the driver + * + * Tear down the driver communication with the device, reload the + * firmware and reinitialize the communication with the device. + * + * If someone calls a reset when the device's firmware is down, in + * theory we won't see it because we are not listening. However, just + * in case, leave the code to handle it. + * + * If there is a reset context, use it; this means someone is waiting + * for us to tell him when the reset operation is complete and the + * device is ready to rock again. + * + * NOTE: if we are in the process of bringing up or down the + * communication with the device [running i2400m_dev_start() or + * _stop()], don't do anything, let it fail and handle it. + * + * This function is ran always in a thread context + * + * This function gets passed, as payload to i2400m_work() a 'const + * char *' ptr with a "reason" why the reset happened (for messages). + */ +static +void __i2400m_dev_reset_handle(struct work_struct *ws) +{ + 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; + 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 + * i2400m_dev_stop() [we are shutting down anyway, so + * ignore it] or we are resetting somewhere else. */ + dev_err(dev, "device rebooted somewhere else?\n"); + i2400m_msg_to_dev_cancel_wait(i2400m, -EL3RST); + complete(&i2400m->msg_completion); + goto out; + } + + dev_err(dev, "%s: reinitializing driver\n", reason); + rmb(); + if (i2400m->updown) { + __i2400m_dev_stop(i2400m); + i2400m->updown = 0; + wmb(); /* see i2400m->updown's documentation */ + } + + 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: + d_fnend(3, dev, "(ws %p i2400m %p reason %s) = void\n", + ws, i2400m, reason); +} + + +/** + * i2400m_dev_reset_handle - Handle a device's reset in a thread context + * + * Schedule a device reset handling out on a thread context, so it + * is safe to call from atomic context. We can't use the i2400m's + * queue as we are going to destroy it and reinitialize it as part of + * the driver bringup/bringup process. + * + * See __i2400m_dev_reset_handle() for details; that takes care of + * reinitializing the driver to handle the reset, calling into the + * bus-specific functions ops as needed. + */ +int i2400m_dev_reset_handle(struct i2400m *i2400m, const char *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. + */ +static +int i2400m_bm_buf_alloc(struct i2400m *i2400m) +{ + int result; + + result = -ENOMEM; + i2400m->bm_cmd_buf = kzalloc(I2400M_BM_CMD_BUF_SIZE, GFP_KERNEL); + if (i2400m->bm_cmd_buf == NULL) + goto error_bm_cmd_kzalloc; + i2400m->bm_ack_buf = kzalloc(I2400M_BM_ACK_BUF_SIZE, GFP_KERNEL); + if (i2400m->bm_ack_buf == NULL) + goto error_bm_ack_buf_kzalloc; + return 0; + +error_bm_ack_buf_kzalloc: + kfree(i2400m->bm_cmd_buf); +error_bm_cmd_kzalloc: + return result; +} + + +/* + * Free boot mode command and ack buffers. + */ +static +void i2400m_bm_buf_free(struct i2400m *i2400m) +{ + kfree(i2400m->bm_ack_buf); + kfree(i2400m->bm_cmd_buf); +} + + +/** + * i2400m_init - Initialize a 'struct i2400m' from all zeroes + * + * This is a bus-generic API call. + */ +void i2400m_init(struct i2400m *i2400m) +{ + wimax_dev_init(&i2400m->wimax_dev); + + i2400m->boot_mode = 1; + i2400m->rx_reorder = 1; + init_waitqueue_head(&i2400m->state_wq); + + spin_lock_init(&i2400m->tx_lock); + i2400m->tx_pl_min = UINT_MAX; + i2400m->tx_size_min = UINT_MAX; + + spin_lock_init(&i2400m->rx_lock); + i2400m->rx_pl_min = UINT_MAX; + i2400m->rx_size_min = UINT_MAX; + INIT_LIST_HEAD(&i2400m->rx_reports); + INIT_WORK(&i2400m->rx_report_ws, i2400m_report_hook_work); + + mutex_init(&i2400m->msg_mutex); + init_completion(&i2400m->msg_completion); + + 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); + + +int i2400m_reset(struct i2400m *i2400m, enum i2400m_reset_type rt) +{ + struct net_device *net_dev = i2400m->wimax_dev.net_dev; + + /* + * Make sure we stop TXs and down the carrier before + * resetting; this is needed to avoid things like + * i2400m_wake_tx() scheduling stuff in parallel. + */ + if (net_dev->reg_state == NETREG_REGISTERED) { + netif_tx_disable(net_dev); + netif_carrier_off(net_dev); + } + return i2400m->bus_reset(i2400m, rt); +} +EXPORT_SYMBOL_GPL(i2400m_reset); + + +/** + * i2400m_setup - bus-generic setup function for the i2400m device + * + * @i2400m: device descriptor (bus-specific parts have been initialized) + * + * Returns: 0 if ok, < 0 errno code on error. + * + * Sets up basic device comunication infrastructure, boots the ROM to + * read the MAC address, registers with the WiMAX and network stacks + * and then brings up the device. + */ +int i2400m_setup(struct i2400m *i2400m, enum i2400m_bri bm_flags) +{ + int result = -ENODEV; + struct device *dev = i2400m_dev(i2400m); + struct wimax_dev *wimax_dev = &i2400m->wimax_dev; + struct net_device *net_dev = i2400m->wimax_dev.net_dev; + + d_fnstart(3, dev, "(i2400m %p)\n", i2400m); + + snprintf(wimax_dev->name, sizeof(wimax_dev->name), + "i2400m-%s:%s", dev->bus->name, dev_name(dev)); + + result = i2400m_bm_buf_alloc(i2400m); + if (result < 0) { + dev_err(dev, "cannot allocate bootmode scratch buffers\n"); + goto error_bm_buf_alloc; + } + + if (i2400m->bus_setup) { + result = i2400m->bus_setup(i2400m); + if (result < 0) { + dev_err(dev, "bus-specific setup failed: %d\n", + result); + goto error_bus_setup; + } + } + + result = i2400m_bootrom_init(i2400m, bm_flags); + if (result < 0) { + dev_err(dev, "read mac addr: bootrom init " + "failed: %d\n", result); + goto error_bootrom_init; + } + result = i2400m_read_mac_addr(i2400m); + if (result < 0) + goto error_read_mac_addr; + eth_random_addr(i2400m->src_mac_addr); + + i2400m->pm_notifier.notifier_call = i2400m_pm_notifier; + register_pm_notifier(&i2400m->pm_notifier); + + result = register_netdev(net_dev); /* Okey dokey, bring it up */ + if (result < 0) { + dev_err(dev, "cannot register i2400m network device: %d\n", + result); + goto error_register_netdev; + } + netif_carrier_off(net_dev); + + i2400m->wimax_dev.op_msg_from_user = i2400m_op_msg_from_user; + i2400m->wimax_dev.op_rfkill_sw_toggle = i2400m_op_rfkill_sw_toggle; + i2400m->wimax_dev.op_reset = i2400m_op_reset; + + result = wimax_dev_add(&i2400m->wimax_dev, net_dev); + if (result < 0) + goto error_wimax_dev_add; + + /* Now setup all that requires a registered net and wimax device. */ + result = sysfs_create_group(&net_dev->dev.kobj, &i2400m_dev_attr_group); + if (result < 0) { + dev_err(dev, "cannot setup i2400m's sysfs: %d\n", result); + goto error_sysfs_setup; + } + + result = i2400m_debugfs_add(i2400m); + if (result < 0) { + dev_err(dev, "cannot setup i2400m's debugfs: %d\n", result); + goto error_debugfs_setup; + } + + result = i2400m_dev_start(i2400m, bm_flags); + if (result < 0) + goto error_dev_start; + d_fnend(3, dev, "(i2400m %p) = %d\n", i2400m, result); + return result; + +error_dev_start: + i2400m_debugfs_rm(i2400m); +error_debugfs_setup: + sysfs_remove_group(&i2400m->wimax_dev.net_dev->dev.kobj, + &i2400m_dev_attr_group); +error_sysfs_setup: + wimax_dev_rm(&i2400m->wimax_dev); +error_wimax_dev_add: + unregister_netdev(net_dev); +error_register_netdev: + unregister_pm_notifier(&i2400m->pm_notifier); +error_read_mac_addr: +error_bootrom_init: + if (i2400m->bus_release) + i2400m->bus_release(i2400m); +error_bus_setup: + i2400m_bm_buf_free(i2400m); +error_bm_buf_alloc: + d_fnend(3, dev, "(i2400m %p) = %d\n", i2400m, result); + return result; +} +EXPORT_SYMBOL_GPL(i2400m_setup); + + +/** + * i2400m_release - release the bus-generic driver resources + * + * Sends a disconnect message and undoes any setup done by i2400m_setup() + */ +void i2400m_release(struct i2400m *i2400m) +{ + struct device *dev = i2400m_dev(i2400m); + + d_fnstart(3, dev, "(i2400m %p)\n", i2400m); + netif_stop_queue(i2400m->wimax_dev.net_dev); + + 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); + wimax_dev_rm(&i2400m->wimax_dev); + unregister_netdev(i2400m->wimax_dev.net_dev); + unregister_pm_notifier(&i2400m->pm_notifier); + if (i2400m->bus_release) + i2400m->bus_release(i2400m); + i2400m_bm_buf_free(i2400m); + d_fnend(3, dev, "(i2400m %p) = void\n", i2400m); +} +EXPORT_SYMBOL_GPL(i2400m_release); + + +/* + * Debug levels control; see debug.h + */ +struct d_level D_LEVEL[] = { + D_SUBMODULE_DEFINE(control), + D_SUBMODULE_DEFINE(driver), + D_SUBMODULE_DEFINE(debugfs), + D_SUBMODULE_DEFINE(fw), + D_SUBMODULE_DEFINE(netdev), + D_SUBMODULE_DEFINE(rfkill), + D_SUBMODULE_DEFINE(rx), + D_SUBMODULE_DEFINE(sysfs), + D_SUBMODULE_DEFINE(tx), +}; +size_t D_LEVEL_SIZE = ARRAY_SIZE(D_LEVEL); + + +static +int __init i2400m_driver_init(void) +{ + d_parse_params(D_LEVEL, D_LEVEL_SIZE, i2400m_debug_params, + "i2400m.debug"); + return i2400m_barker_db_init(i2400m_barkers_params); +} +module_init(i2400m_driver_init); + +static +void __exit i2400m_driver_exit(void) +{ + i2400m_barker_db_exit(); +} +module_exit(i2400m_driver_exit); + +MODULE_AUTHOR("Intel Corporation <linux-wimax@intel.com>"); +MODULE_DESCRIPTION("Intel 2400M WiMAX networking bus-generic driver"); +MODULE_LICENSE("GPL"); |