i2400m: Generic probe/disconnect, reset and message passing

Implements the generic probe and disconnect functions that will be
called by the USB and SDIO driver's probe/disconnect functions.

Implements the backends for the WiMAX stack's basic operations:
message passing, rfkill control and reset.
Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/net/wimax/i2400m/driver.c

+/*
+ * 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_bootrom_init()
+ *   register_netdev()
+ *   i2400m_dev_start()
+ *     __i2400m_dev_start()
+ *       i2400m_dev_bootstrap()
+ *       i2400m_tx_setup()
+ *       i2400m->bus_dev_start()
+ *       i2400m_check_mac_addr()
+ *   wimax_dev_add()
+ *
+ * i2400m_release()
+ *   wimax_dev_rm()
+ *   i2400m_dev_stop()
+ *     __i2400m_dev_stop()
+ *       i2400m_dev_shutdown()
+ *       i2400m->bus_dev_stop()
+ *       i2400m_tx_release()
+ *   unregister_netdev()
+ */
+#include "i2400m.h"
+#include <linux/wimax/i2400m.h>
+#include <linux/module.h>
+#include <linux/moduleparam.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.");
+
+/**
+ * i2400m_queue_work - schedule work on a i2400m's queue
+ *
+ * @i2400m: device descriptor
+ *
+ * @fn: function to run to execute work. It gets passed a 'struct
+ *     work_struct' that is wrapped in a 'struct i2400m_work'. Once
+ *     done, you have to (1) i2400m_put(i2400m_work->i2400m) and then
+ *     (2) kfree(i2400m_work).
+ *
+ * @gfp_flags: GFP flags for memory allocation.
+ *
+ * @pl: pointer to a payload buffer that you want to pass to the _work
+ *     function. Use this to pack (for example) a struct with extra
+ *     arguments.
+ *
+ * @pl_size: size of the payload buffer.
+ *
+ * We do this quite often, so this just saves typing; allocate a
+ * wrapper for a i2400m, get a ref to it, pack arguments and launch
+ * the work.
+ *
+ * A usual workflow is:
+ *
+ * struct my_work_args {
+ *         void *something;
+ *         int whatever;
+ * };
+ * ...
+ *
+ * struct my_work_args my_args = {
+ *         .something = FOO,
+ *         .whaetever = BLAH
+ * };
+ * i2400m_queue_work(i2400m, 1, my_work_function, GFP_KERNEL,
+ *                   &args, sizeof(args))
+ *
+ * And now the work function can unpack the arguments and call the
+ * real function (or do the job itself):
+ *
+ * static
+ * void my_work_fn((struct work_struct *ws)
+ * {
+ *         struct i2400m_work *iw =
+ *	           container_of(ws, struct i2400m_work, ws);
+ *	   struct my_work_args *my_args = (void *) iw->pl;
+ *
+ *	   my_work(iw->i2400m, my_args->something, my_args->whatevert);
+ * }
+ */
+int i2400m_queue_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;
+
+	BUG_ON(i2400m->work_queue == NULL);
+	result = -ENOMEM;
+	iw = kzalloc(sizeof(*iw) + pl_size, gfp_flags);
+	if (iw == NULL)
+		goto error_kzalloc;
+	iw->i2400m = i2400m_get(i2400m);
+	memcpy(iw->pl, pl, pl_size);
+	INIT_WORK(&iw->ws, fn);
+	result = queue_work(i2400m->work_queue, &iw->ws);
+error_kzalloc:
+	return result;
+}
+EXPORT_SYMBOL_GPL(i2400m_queue_work);
+
+
+/*
+ * 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)
+{
+	int result;
+	struct i2400m_work *iw;
+
+	BUG_ON(i2400m->work_queue == NULL);
+	result = -ENOMEM;
+	iw = kzalloc(sizeof(*iw), gfp_flags);
+	if (iw == NULL)
+		goto error_kzalloc;
+	iw->i2400m = i2400m_get(i2400m);
+	INIT_WORK(&iw->ws, fn);
+	result = schedule_work(&iw->ws);
+	if (result == 0)
+		result = -ENXIO;
+error_kzalloc:
+	return result;
+}
+
+
+/*
+ * 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;
+	if (unlikely(i2400m->trace_msg_from_user))
+		wimax_msg(&i2400m->wimax_dev, "trace",
+			  msg_buf, msg_len, GFP_KERNEL);
+	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->bus_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;
+	const unsigned char zeromac[ETH_ALEN] = { 0 };
+
+	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 addresss */
+	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]);
+	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_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.
+ *
+ * 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 = 3;
+
+	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->bus_dev_start(i2400m);
+	if (result < 0)
+		goto error_bus_dev_start;
+	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;
+	}
+	/* 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;
+	i2400m->ready = 1;
+	wimax_state_change(wimax_dev, WIMAX_ST_UNINITIALIZED);
+	result = i2400m_dev_initialize(i2400m);
+	if (result < 0)
+		goto error_dev_initialize;
+	/* 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:
+	destroy_workqueue(i2400m->work_queue);
+error_create_workqueue:
+	i2400m->bus_dev_stop(i2400m);
+error_bus_dev_start:
+	i2400m_tx_release(i2400m);
+error_tx_setup:
+error_bootstrap:
+	if (result == -ERESTARTSYS && times-- > 0) {
+		flags = I2400M_BRI_SOFT;
+		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;
+	mutex_lock(&i2400m->init_mutex);	/* Well, start the device */
+	result = __i2400m_dev_start(i2400m, bm_flags);
+	if (result >= 0)
+		i2400m->updown = 1;
+	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.
+ */
+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_dev_shutdown(i2400m);
+	i2400m->ready = 0;
+	destroy_workqueue(i2400m->work_queue);
+	i2400m->bus_dev_stop(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;
+	}
+	mutex_unlock(&i2400m->init_mutex);
+}
+
+
+/*
+ * 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
+ */
+static
+void __i2400m_dev_reset_handle(struct work_struct *ws)
+{
+	int result;
+	struct i2400m_work *iw = container_of(ws, struct i2400m_work, ws);
+	struct i2400m *i2400m = iw->i2400m;
+	struct device *dev = i2400m_dev(i2400m);
+	enum wimax_st wimax_state;
+	struct i2400m_reset_ctx *ctx = i2400m->reset_ctx;
+
+	d_fnstart(3, dev, "(ws %p i2400m %p)\n", ws, i2400m);
+	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\n");
+		i2400m_msg_to_dev_cancel_wait(i2400m, -ERESTARTSYS);
+		complete(&i2400m->msg_completion);
+		goto out;
+	}
+	wimax_state = wimax_state_get(&i2400m->wimax_dev);
+	if (wimax_state < WIMAX_ST_UNINITIALIZED) {
+		dev_info(dev, "device rebooted: it is down, ignoring\n");
+		goto out_unlock;	/* ifconfig up/down wasn't called */
+	}
+	dev_err(dev, "device rebooted: reinitializing driver\n");
+	__i2400m_dev_stop(i2400m);
+	i2400m->updown = 0;
+	result = __i2400m_dev_start(i2400m,
+				    I2400M_BRI_SOFT | I2400M_BRI_MAC_REINIT);
+	if (result < 0) {
+		dev_err(dev, "device reboot: cannot start the device: %d\n",
+			result);
+		result = i2400m->bus_reset(i2400m, I2400M_RT_BUS);
+		if (result >= 0)
+			result = -ENODEV;
+	} else
+		i2400m->updown = 1;
+out_unlock:
+	if (i2400m->reset_ctx) {
+		ctx->result = result;
+		complete(&ctx->completion);
+	}
+	mutex_unlock(&i2400m->init_mutex);
+out:
+	i2400m_put(i2400m);
+	kfree(iw);
+	d_fnend(3, dev, "(ws %p i2400m %p) = void\n", ws, i2400m);
+	return;
+}
+
+
+/**
+ * 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)
+{
+	return i2400m_schedule_work(i2400m, __i2400m_dev_reset_handle,
+				    GFP_ATOMIC);
+}
+EXPORT_SYMBOL_GPL(i2400m_dev_reset_handle);
+
+
+/**
+ * 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.
+ *
+ * Initializes the bus-generic parts of the i2400m driver; the
+ * bus-specific parts have been initialized, function pointers filled
+ * out by the bus-specific probe function.
+ *
+ * As well, this registers the WiMAX and net device nodes. Once this
+ * function returns, the device is operative and has to be ready to
+ * receive and send network traffic and WiMAX control operations.
+ */
+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->bus_id);
+
+	i2400m->bm_cmd_buf = kzalloc(I2400M_BM_CMD_BUF_SIZE, GFP_KERNEL);
+	if (i2400m->bm_cmd_buf == NULL) {
+		dev_err(dev, "cannot allocate USB command buffer\n");
+		goto error_bm_cmd_kzalloc;
+	}
+	i2400m->bm_ack_buf = kzalloc(I2400M_BM_ACK_BUF_SIZE, GFP_KERNEL);
+	if (i2400m->bm_ack_buf == NULL) {
+		dev_err(dev, "cannot allocate USB ack buffer\n");
+		goto error_bm_ack_buf_kzalloc;
+	}
+	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;
+
+	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);
+
+	result = i2400m_dev_start(i2400m, bm_flags);
+	if (result < 0)
+		goto error_dev_start;
+
+	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;
+	/* User space needs to do some init stuff */
+	wimax_state_change(wimax_dev, WIMAX_ST_UNINITIALIZED);
+
+	/* Now setup all that requires a registered net and wimax device. */
+	result = i2400m_debugfs_add(i2400m);
+	if (result < 0) {
+		dev_err(dev, "cannot setup i2400m's debugfs: %d\n", result);
+		goto error_debugfs_setup;
+	}
+	d_fnend(3, dev, "(i2400m %p) = %d\n", i2400m, result);
+	return result;
+
+error_debugfs_setup:
+	wimax_dev_rm(&i2400m->wimax_dev);
+error_wimax_dev_add:
+	i2400m_dev_stop(i2400m);
+error_dev_start:
+	unregister_netdev(net_dev);
+error_register_netdev:
+error_read_mac_addr:
+error_bootrom_init:
+	kfree(i2400m->bm_ack_buf);
+error_bm_ack_buf_kzalloc:
+	kfree(i2400m->bm_cmd_buf);
+error_bm_cmd_kzalloc:
+	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_debugfs_rm(i2400m);
+	wimax_dev_rm(&i2400m->wimax_dev);
+	i2400m_dev_stop(i2400m);
+	unregister_netdev(i2400m->wimax_dev.net_dev);
+	kfree(i2400m->bm_ack_buf);
+	kfree(i2400m->bm_cmd_buf);
+	d_fnend(3, dev, "(i2400m %p) = void\n", i2400m);
+}
+EXPORT_SYMBOL_GPL(i2400m_release);
+
+
+static
+int __init i2400m_driver_init(void)
+{
+	return 0;
+}
+module_init(i2400m_driver_init);
+
+static
+void __exit i2400m_driver_exit(void)
+{
+	/* for scheds i2400m_dev_reset_handle() */
+	flush_scheduled_work();
+	return;
+}
+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");

drivers/net/wimax/i2400m/op-rfkill.c

+/*
+ * Intel Wireless WiMAX Connection 2400m
+ * Implement backend for the WiMAX stack rfkill support
+ *
+ *
+ * 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.
+ *
+ *
+ * The WiMAX kernel stack integrates into RF-Kill and keeps the
+ * switches's status. We just need to:
+ *
+ * - report changes in the HW RF Kill switch [with
+ *   wimax_rfkill_{sw,hw}_report(), which happens when we detect those
+ *   indications coming through hardware reports]. We also do it on
+ *   initialization to let the stack know the intial HW state.
+ *
+ * - implement indications from the stack to change the SW RF Kill
+ *   switch (coming from sysfs, the wimax stack or user space).
+ */
+#include "i2400m.h"
+#include <linux/wimax/i2400m.h>
+
+
+
+#define D_SUBMODULE rfkill
+#include "debug-levels.h"
+
+/*
+ * Return true if the i2400m radio is in the requested wimax_rf_state state
+ *
+ */
+static
+int i2400m_radio_is(struct i2400m *i2400m, enum wimax_rf_state state)
+{
+	if (state == WIMAX_RF_OFF)
+		return i2400m->state == I2400M_SS_RF_OFF
+			|| i2400m->state == I2400M_SS_RF_SHUTDOWN;
+	else if (state == WIMAX_RF_ON)
+		/* state == WIMAX_RF_ON */
+		return i2400m->state != I2400M_SS_RF_OFF
+			&& i2400m->state != I2400M_SS_RF_SHUTDOWN;
+	else
+		BUG();
+}
+
+
+/*
+ * WiMAX stack operation: implement SW RFKill toggling
+ *
+ * @wimax_dev: device descriptor
+ * @skb: skb where the message has been received; skb->data is
+ *       expected to point to the message payload.
+ * @genl_info: passed by the generic netlink layer
+ *
+ * Generic Netlink will call this function when a message is sent from
+ * userspace to change the software RF-Kill switch status.
+ *
+ * This function will set the device's sofware RF-Kill switch state to
+ * match what is requested.
+ *
+ * NOTE: the i2400m has a strict state machine; we can only set the
+ *       RF-Kill switch when it is on, the HW RF-Kill is on and the
+ *       device is initialized. So we ignore errors steaming from not
+ *       being in the right state (-EILSEQ).
+ */
+int i2400m_op_rfkill_sw_toggle(struct wimax_dev *wimax_dev,
+			       enum wimax_rf_state state)
+{
+	int result;
+	struct i2400m *i2400m = wimax_dev_to_i2400m(wimax_dev);
+	struct device *dev = i2400m_dev(i2400m);
+	struct sk_buff *ack_skb;
+	struct {
+		struct i2400m_l3l4_hdr hdr;
+		struct i2400m_tlv_rf_operation sw_rf;
+	} __attribute__((packed)) *cmd;
+	char strerr[32];
+
+	d_fnstart(4, dev, "(wimax_dev %p state %d)\n", wimax_dev, state);
+
+	result = -ENOMEM;
+	cmd = kzalloc(sizeof(*cmd), GFP_KERNEL);
+	if (cmd == NULL)
+		goto error_alloc;
+	cmd->hdr.type = cpu_to_le16(I2400M_MT_CMD_RF_CONTROL);
+	cmd->hdr.length = sizeof(cmd->sw_rf);
+	cmd->hdr.version = cpu_to_le16(I2400M_L3L4_VERSION);
+	cmd->sw_rf.hdr.type = cpu_to_le16(I2400M_TLV_RF_OPERATION);
+	cmd->sw_rf.hdr.length = cpu_to_le16(sizeof(cmd->sw_rf.status));
+	switch (state) {
+	case WIMAX_RF_OFF:	/* RFKILL ON, radio OFF */
+		cmd->sw_rf.status = cpu_to_le32(2);
+		break;
+	case WIMAX_RF_ON:	/* RFKILL OFF, radio ON */
+		cmd->sw_rf.status = cpu_to_le32(1);
+		break;
+	default:
+		BUG();
+	}
+
+	ack_skb = i2400m_msg_to_dev(i2400m, cmd, sizeof(*cmd));
+	result = PTR_ERR(ack_skb);
+	if (IS_ERR(ack_skb)) {
+		dev_err(dev, "Failed to issue 'RF Control' command: %d\n",
+			result);
+		goto error_msg_to_dev;
+	}
+	result = i2400m_msg_check_status(wimax_msg_data(ack_skb),
+					 strerr, sizeof(strerr));
+	if (result < 0) {
+		dev_err(dev, "'RF Control' (0x%04x) command failed: %d - %s\n",
+			I2400M_MT_CMD_RF_CONTROL, result, strerr);
+		goto error_cmd;
+	}
+
+	/* Now we wait for the state to change to RADIO_OFF or RADIO_ON */
+	result = wait_event_timeout(
+		i2400m->state_wq, i2400m_radio_is(i2400m, state),
+		5 * HZ);
+	if (result == 0)
+		result = -ETIMEDOUT;
+	if (result < 0)
+		dev_err(dev, "Error waiting for device to toggle RF state: "
+			"%d\n", result);
+	result = 0;
+error_cmd:
+	kfree_skb(ack_skb);
+error_msg_to_dev:
+error_alloc:
+	d_fnend(4, dev, "(wimax_dev %p state %d) = %d\n",
+		wimax_dev, state, result);
+	return result;
+}
+
+
+/*
+ * Inform the WiMAX stack of changes in the RF Kill switches reported
+ * by the device
+ *
+ * @i2400m: device descriptor
+ * @rfss: TLV for RF Switches status; already validated
+ *
+ * NOTE: the reports on RF switch status cannot be trusted
+ *       or used until the device is in a state of RADIO_OFF
+ *       or greater.
+ */
+void i2400m_report_tlv_rf_switches_status(
+	struct i2400m *i2400m,
+	const struct i2400m_tlv_rf_switches_status *rfss)
+{
+	struct device *dev = i2400m_dev(i2400m);
+	enum i2400m_rf_switch_status hw, sw;
+	enum wimax_st wimax_state;
+
+	sw = le32_to_cpu(rfss->sw_rf_switch);
+	hw = le32_to_cpu(rfss->hw_rf_switch);
+
+	d_fnstart(3, dev, "(i2400m %p rfss %p [hw %u sw %u])\n",
+		  i2400m, rfss, hw, sw);
+	/* We only process rw switch evens when the device has been
+	 * fully initialized */
+	wimax_state = wimax_state_get(&i2400m->wimax_dev);
+	if (wimax_state < WIMAX_ST_RADIO_OFF) {
+		d_printf(3, dev, "ignoring RF switches report, state %u\n",
+			 wimax_state);
+		goto out;
+	}
+	switch (sw) {
+	case I2400M_RF_SWITCH_ON:	/* RF Kill disabled (radio on) */
+		wimax_report_rfkill_sw(&i2400m->wimax_dev, WIMAX_RF_ON);
+		break;
+	case I2400M_RF_SWITCH_OFF:	/* RF Kill enabled (radio off) */
+		wimax_report_rfkill_sw(&i2400m->wimax_dev, WIMAX_RF_OFF);
+		break;
+	default:
+		dev_err(dev, "HW BUG? Unknown RF SW state 0x%x\n", sw);
+	}
+
+	switch (hw) {
+	case I2400M_RF_SWITCH_ON:	/* RF Kill disabled (radio on) */
+		wimax_report_rfkill_hw(&i2400m->wimax_dev, WIMAX_RF_ON);
+		break;
+	case I2400M_RF_SWITCH_OFF:	/* RF Kill enabled (radio off) */
+		wimax_report_rfkill_hw(&i2400m->wimax_dev, WIMAX_RF_OFF);
+		break;
+	default:
+		dev_err(dev, "HW BUG? Unknown RF HW state 0x%x\n", hw);
+	}
+out:
+	d_fnend(3, dev, "(i2400m %p rfss %p [hw %u sw %u]) = void\n",
+		i2400m, rfss, hw, sw);
+}