[PATCH 17/29] i2400m: various functions for device management

[Inaky Perez-Gonzalez <inaky@linux.intel.com>]

This is a collection of functions used to control the device (plus a
few helpers).

There are utilities for handling TLV buffers, hooks on the device's
reports to act on device changes of state [i2400m_report_hook()], on
acks to commands [i2400m_msg_ack_hook()], a helper for sending
commands to the device and blocking until a reply arrives
[i2400m_msg_to_dev()], a few high level commands for manipulating the
device state, powersaving mode and configuration plus the routines to
setup the device once communication is established with it
[i2400m_dev_initialize()].

Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com>
---
 drivers/net/wimax/i2400m/control.c | 1291 ++++++++++++++++++++++++++++++++++++
 1 files changed, 1291 insertions(+), 0 deletions(-)
 create mode 100644 drivers/net/wimax/i2400m/control.c

diff --git a/drivers/net/wimax/i2400m/control.c b/drivers/net/wimax/i2400m/control.c
new file mode 100644
index 0000000..d3d37fe
--- /dev/null
+++ b/drivers/net/wimax/i2400m/control.c
@@ -0,0 +1,1291 @@
+/*
+ * Intel Wireless WiMAX Connection 2400m
+ * Miscellaneous control functions for managing the device
+ *
+ *
+ * Copyright (C) 2007-2008 Intel Corporation. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ *   * Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in
+ *     the documentation and/or other materials provided with the
+ *     distribution.
+ *   * Neither the name of Intel Corporation nor the names of its
+ *     contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ *
+ * Intel Corporation <linux-wimax@intel.com>
+ * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
+ *  - Initial implementation
+ *
+ * This is a collection of functions used to control the device (plus
+ * a few helpers).
+ *
+ * There are utilities for handling TLV buffers, hooks on the device's
+ * reports to act on device changes of state [i2400m_report_hook()],
+ * on acks to commands [i2400m_msg_ack_hook()], a helper for sending
+ * commands to the device and blocking until a reply arrives
+ * [i2400m_msg_to_dev()], a few high level commands for manipulating
+ * the device state, powersving mode and configuration plus the
+ * routines to setup the device once communication is stablished with
+ * it [i2400m_dev_initialize()].
+ *
+ * ROADMAP
+ *
+ * i2400m_dev_initalize()       Called by i2400m_dev_start()
+ *   i2400m_set_init_config()
+ *   i2400m_firmware_check()
+ *   i2400m_cmd_get_state()
+ * i2400m_dev_shutdown()        Called by i2400m_dev_stop()
+ *   i2400m->bus_reset()
+ *
+ * i2400m_{cmd,get,set}_*()
+ *   i2400m_msg_to_dev()
+ *   i2400m_msg_check_status()
+ *
+ * i2400m_report_hook()         Called on reception of an event
+ *   i2400m_report_state_hook()
+ *     i2400m_tlv_buffer_walk()
+ *     i2400m_tlv_match()
+ *     i2400m_report_tlv_system_state()
+ *     i2400m_report_tlv_rf_switches_status()
+ *     i2400m_report_tlv_media_status()
+ *   i2400m_cmd_enter_powersave()
+ *
+ * i2400m_msg_ack_hook()        Called on reception of a reply to a
+ *                              command, get or set
+ */
+
+#include <stdarg.h>
+#include "i2400m.h"
+#include <linux/kernel.h>
+#include <linux/wimax/i2400m.h>
+
+
+#define D_SUBMODULE control
+#include "debug-levels.h"
+
+
+/*
+ * Return if a TLV is of a give type and size
+ *
+ * @tlv_hdr: pointer to the TLV
+ * @tlv_type: type of the TLV we are looking for
+ * @tlv_size: expected size of the TLV we are looking for (if -1,
+ *            don't check the size). This includes the header
+ * Returns: 0 if the TLV matches
+ *          < 0 if it doesn't match at all
+ *          > 0 total TLV + payload size, if the type matches, but not
+ *              the size
+ */
+static
+ssize_t i2400m_tlv_match(const struct i2400m_tlv_hdr *tlv,
+		     enum i2400m_tlv tlv_type, ssize_t tlv_size)
+{
+	if (le16_to_cpu(tlv->type) != tlv_type)	/* Not our type? skip */
+		return -1;
+	if (tlv_size != -1
+	    && le16_to_cpu(tlv->length) + sizeof(*tlv) != tlv_size) {
+		size_t size = le16_to_cpu(tlv->length) + sizeof(*tlv);
+		printk(KERN_WARNING "W: tlv type 0x%x mismatched because of "
+		       "size (got %zu vs %zu expected)\n",
+		       tlv_type, size, tlv_size);
+		return size;
+	}
+	return 0;
+}
+
+
+/*
+ * Given a buffer of TLVs, iterate over them
+ *
+ * @i2400m: device instance
+ * @tlv_buf: pointer to the beginning of the TLV buffer
+ * @buf_size: buffer size in bytes
+ * @tlv_pos: seek position; this is assumed to be a pointer returned
+ *           by i2400m_tlv_buffer_walk() [and thus, validated]. The
+ *           TLV returned will be the one following this one.
+ *
+ * Usage:
+ *
+ * tlv_itr = NULL;
+ * while (tlv_itr = i2400m_tlv_buffer_walk(i2400m, buf, size, tlv_itr))  {
+ *         ...
+ *         // Do stuff with tlv_itr, DON'T MODIFY IT
+ *         ...
+ * }
+ */
+static
+const struct i2400m_tlv_hdr *i2400m_tlv_buffer_walk(
+	struct i2400m *i2400m,
+	const void *tlv_buf, size_t buf_size,
+	const struct i2400m_tlv_hdr *tlv_pos)
+{
+	struct device *dev = i2400m_dev(i2400m);
+	const struct i2400m_tlv_hdr *tlv_top = tlv_buf + buf_size;
+	size_t offset, length, avail_size;
+	unsigned type;
+
+	if (tlv_pos == NULL)	/* Take the first one? */
+		tlv_pos = tlv_buf;
+	else			/* Nope, the next one */
+		tlv_pos = (void *) tlv_pos
+			+ le16_to_cpu(tlv_pos->length) + sizeof(*tlv_pos);
+	if (tlv_pos == tlv_top) {	/* buffer done */
+		tlv_pos = NULL;
+		goto error_beyond_end;
+	}
+	if (tlv_pos > tlv_top) {
+		tlv_pos = NULL;
+		WARN_ON(1);
+		goto error_beyond_end;
+	}
+	offset = (void *) tlv_pos - (void *) tlv_buf;
+	avail_size = buf_size - offset;
+	if (avail_size < sizeof(*tlv_pos)) {
+		dev_err(dev, "HW BUG? tlv_buf %p [%zu bytes], tlv @%zu: "
+			"short header\n", tlv_buf, buf_size, offset);
+		goto error_short_header;
+	}
+	type = le16_to_cpu(tlv_pos->type);
+	length = le16_to_cpu(tlv_pos->length);
+	if (avail_size < sizeof(*tlv_pos) + length) {
+		dev_err(dev, "HW BUG? tlv_buf %p [%zu bytes], "
+			"tlv type 0x%04x @%zu: "
+			"short data (%zu bytes vs %zu needed)\n",
+			tlv_buf, buf_size, type, offset, avail_size,
+			sizeof(*tlv_pos) + length);
+		goto error_short_header;
+	}
+error_short_header:
+error_beyond_end:
+	return tlv_pos;
+}
+
+
+/*
+ * Find a TLV in a buffer of sequential TLVs
+ *
+ * @i2400m: device descriptor
+ * @tlv_hdr: pointer to the first TLV in the sequence
+ * @size: size of the buffer in bytes; all TLVs are assumed to fit
+ *        fully in the buffer (otherwise we'll complain).
+ * @tlv_type: type of the TLV we are looking for
+ * @tlv_size: expected size of the TLV we are looking for (if -1,
+ *            don't check the size). This includes the header
+ *
+ * Returns: NULL if the TLV is not found, otherwise a pointer to
+ *          it. If the sizes don't match, an error is printed and NULL
+ *          returned.
+ */
+static
+const struct i2400m_tlv_hdr *i2400m_tlv_find(
+	struct i2400m *i2400m,
+	const struct i2400m_tlv_hdr *tlv_hdr, size_t size,
+	enum i2400m_tlv tlv_type, ssize_t tlv_size)
+{
+	ssize_t match;
+	struct device *dev = i2400m_dev(i2400m);
+	const struct i2400m_tlv_hdr *tlv = NULL;
+	while ((tlv = i2400m_tlv_buffer_walk(i2400m, tlv_hdr, size, tlv))) {
+		match = i2400m_tlv_match(tlv, tlv_type, tlv_size);
+		if (match == 0)		/* found it :) */
+			break;
+		if (match > 0)
+			dev_warn(dev, "TLV type 0x%04x found with size "
+				 "mismatch (%zu vs %zu needed)\n",
+				 tlv_type, match, tlv_size);
+	}
+	return tlv;
+}
+
+
+static const struct
+{
+	char *msg;
+	int errno;
+} ms_to_errno[I2400M_MS_MAX] = {
+	[I2400M_MS_DONE_OK] = { "", 0 },
+	[I2400M_MS_DONE_IN_PROGRESS] = { "", 0 },
+	[I2400M_MS_INVALID_OP] = { "invalid opcode", -ENOSYS },
+	[I2400M_MS_BAD_STATE] = { "invalid state", -EILSEQ },
+	[I2400M_MS_ILLEGAL_VALUE] = { "illegal value", -EINVAL },
+	[I2400M_MS_MISSING_PARAMS] = { "missing parameters", -ENOMSG },
+	[I2400M_MS_VERSION_ERROR] = { "bad version", -EIO },
+	[I2400M_MS_ACCESSIBILITY_ERROR] = { "accesibility error", -EIO },
+	[I2400M_MS_BUSY] = { "busy", -EBUSY },
+	[I2400M_MS_CORRUPTED_TLV] = { "corrupted TLV", -EILSEQ },
+	[I2400M_MS_UNINITIALIZED] = { "not unitialized", -EILSEQ },
+	[I2400M_MS_UNKNOWN_ERROR] = { "unknown error", -EIO },
+	[I2400M_MS_PRODUCTION_ERROR] = { "production error", -EIO },
+	[I2400M_MS_NO_RF] = { "no RF", -EIO },
+	[I2400M_MS_NOT_READY_FOR_POWERSAVE] =
+		{ "not ready for powersave", -EACCES },
+	[I2400M_MS_THERMAL_CRITICAL] = { "thermal critical", -EL3HLT },
+};
+
+
+/*
+ * i2400m_msg_check_status - translate a message's status code
+ *
+ * @i2400m: device descriptor
+ * @l3l4_hdr: message header
+ * @strbuf: buffer to place a formatted error message (unless NULL).
+ * @strbuf_size: max amount of available space; larger messages will
+ * be truncated.
+ *
+ * Returns: errno code corresponding to the status code in @l3l4_hdr
+ *          and a message in @strbuf describing the error.
+ */
+int i2400m_msg_check_status(const struct i2400m_l3l4_hdr *l3l4_hdr,
+			    char *strbuf, size_t strbuf_size)
+{
+	int result;
+	enum i2400m_ms status = le16_to_cpu(l3l4_hdr->status);
+	const char *str;
+
+	if (status == 0)
+		return 0;
+	if (status > ARRAY_SIZE(ms_to_errno)) {
+		str = "unknown status code";
+		result = -EBADR;
+	} else {
+		str = ms_to_errno[status].msg;
+		result = ms_to_errno[status].errno;
+	}
+	if (strbuf)
+		snprintf(strbuf, strbuf_size, "%s (%d)", str, status);
+	return result;
+}
+
+
+/*
+ * Act on a TLV System State reported by the device
+ *
+ * @i2400m: device descriptor
+ * @ss: validated System State TLV
+ */
+static
+void i2400m_report_tlv_system_state(struct i2400m *i2400m,
+				    const struct i2400m_tlv_system_state *ss)
+{
+	struct device *dev = i2400m_dev(i2400m);
+	struct wimax_dev *wimax_dev = &i2400m->wimax_dev;
+	enum i2400m_system_state i2400m_state = le32_to_cpu(ss->state);
+
+	d_fnstart(3, dev, "(i2400m %p ss %p [%u])\n", i2400m, ss, i2400m_state);
+
+	if (unlikely(i2400m->ready == 0))	/* act if up */
+		goto out;
+	if (i2400m->state != i2400m_state) {
+		i2400m->state = i2400m_state;
+		wake_up_all(&i2400m->state_wq);
+	}
+	switch (i2400m_state) {
+	case I2400M_SS_UNINITIALIZED:
+	case I2400M_SS_INIT:
+	case I2400M_SS_CONFIG:
+	case I2400M_SS_PRODUCTION:
+		wimax_state_change(wimax_dev, WIMAX_ST_UNINITIALIZED);
+		break;
+
+	case I2400M_SS_RF_OFF:
+	case I2400M_SS_RF_SHUTDOWN:
+		wimax_state_change(wimax_dev, WIMAX_ST_RADIO_OFF);
+		break;
+
+	case I2400M_SS_READY:
+	case I2400M_SS_STANDBY:
+	case I2400M_SS_SLEEPACTIVE:
+		wimax_state_change(wimax_dev, WIMAX_ST_READY);
+		break;
+
+	case I2400M_SS_CONNECTING:
+	case I2400M_SS_WIMAX_CONNECTED:
+		wimax_state_change(wimax_dev, WIMAX_ST_READY);
+		break;
+
+	case I2400M_SS_SCAN:
+	case I2400M_SS_OUT_OF_ZONE:
+		wimax_state_change(wimax_dev, WIMAX_ST_SCANNING);
+		break;
+
+	case I2400M_SS_IDLE:
+		d_printf(1, dev, "entering BS-negotiated idle mode\n");
+	case I2400M_SS_DISCONNECTING:
+	case I2400M_SS_DATA_PATH_CONNECTED:
+		wimax_state_change(wimax_dev, WIMAX_ST_CONNECTED);
+		break;
+
+	default:
+		/* Huh? just in case, shut it down */
+		dev_err(dev, "HW BUG? unknown state %u: shutting down\n",
+			i2400m_state);
+		i2400m->bus_reset(i2400m, I2400M_RT_WARM);
+		break;
+	};
+out:
+	d_fnend(3, dev, "(i2400m %p ss %p [%u]) = void\n",
+		i2400m, ss, i2400m_state);
+}
+
+
+/*
+ * Parse and act on a TLV Media Status sent by the device
+ *
+ * @i2400m: device descriptor
+ * @ms: validated Media Status TLV
+ *
+ * This will set the carrier up on down based on the device's link
+ * report. This is done asides of what the WiMAX stack does based on
+ * the device's state as sometimes we need to do a link-renew (the BS
+ * wants us to renew a DHCP lease, for example).
+ *
+ * In fact, doc says that everytime we get a link-up, we should do a
+ * DHCP negotiation...
+ */
+static
+void i2400m_report_tlv_media_status(struct i2400m *i2400m,
+				    const struct i2400m_tlv_media_status *ms)
+{
+	struct device *dev = i2400m_dev(i2400m);
+	struct wimax_dev *wimax_dev = &i2400m->wimax_dev;
+	struct net_device *net_dev = wimax_dev->net_dev;
+	enum i2400m_media_status status = le32_to_cpu(ms->media_status);
+
+	d_fnstart(3, dev, "(i2400m %p ms %p [%u])\n", i2400m, ms, status);
+
+	if (unlikely(i2400m->ready == 0))	/* act if up */
+		goto out;
+	switch (status) {
+	case I2400M_MEDIA_STATUS_LINK_UP:
+		netif_carrier_on(net_dev);
+		break;
+	case I2400M_MEDIA_STATUS_LINK_DOWN:
+		netif_carrier_off(net_dev);
+		break;
+	/*
+	 * This is the network telling us we need to retrain the DHCP
+	 * lease -- so far, we are trusting the WiMAX Network Service
+	 * in user space to pick this up and poke the DHCP client.
+	 */
+	case I2400M_MEDIA_STATUS_LINK_RENEW:
+		netif_carrier_on(net_dev);
+		break;
+	default:
+		dev_err(dev, "HW BUG? unknown media status %u\n",
+			status);
+	};
+out:
+	d_fnend(3, dev, "(i2400m %p ms %p [%u]) = void\n",
+		i2400m, ms, status);
+}
+
+
+/*
+ * Parse a 'state report' and extract carrier on/off information
+ *
+ * @i2400m: device descriptor
+ * @l3l4_hdr: pointer to message; it has been already validated for
+ *            consistent size.
+ * @size: size of the message (header + payload). The header length
+ *        declaration is assumed to be congruent with @size (as in
+ *        sizeof(*l3l4_hdr) + l3l4_hdr->length == size)
+ *
+ * Extract from the report state the system state TLV and infer from
+ * there if we have a carrier or not. Update our local state and tell
+ * netdev.
+ *
+ * When setting the carrier, it's fine to set OFF twice (for example),
+ * as netif_carrier_off() will not generate two OFF events (just on
+ * the transitions).
+ */
+static
+void i2400m_report_state_hook(struct i2400m *i2400m,
+			      const struct i2400m_l3l4_hdr *l3l4_hdr,
+			      size_t size, const char *tag)
+{
+	struct device *dev = i2400m_dev(i2400m);
+	const struct i2400m_tlv_hdr *tlv;
+	const struct i2400m_tlv_system_state *ss;
+	const struct i2400m_tlv_rf_switches_status *rfss;
+	const struct i2400m_tlv_media_status *ms;
+	size_t tlv_size = le16_to_cpu(l3l4_hdr->length);
+
+	d_fnstart(4, dev, "(i2400m %p, l3l4_hdr %p, size %zu, %s)\n",
+		  i2400m, l3l4_hdr, size, tag);
+	tlv = NULL;
+
+	while ((tlv = i2400m_tlv_buffer_walk(i2400m, &l3l4_hdr->pl,
+					     tlv_size, tlv))) {
+		if (0 == i2400m_tlv_match(tlv, I2400M_TLV_SYSTEM_STATE,
+					  sizeof(*ss))) {
+			ss = container_of(tlv, typeof(*ss), hdr);
+			d_printf(2, dev, "%s: system state TLV "
+				 "found (0x%04x), state 0x%08x\n",
+				 tag, I2400M_TLV_SYSTEM_STATE,
+				 le32_to_cpu(ss->state));
+			i2400m_report_tlv_system_state(i2400m, ss);
+		}
+		if (0 == i2400m_tlv_match(tlv, I2400M_TLV_RF_STATUS,
+					  sizeof(*rfss))) {
+			rfss = container_of(tlv, typeof(*rfss), hdr);
+			d_printf(2, dev, "%s: RF status TLV "
+				 "found (0x%04x), sw 0x%02x hw 0x%02x\n",
+				 tag, I2400M_TLV_RF_STATUS,
+				 le32_to_cpu(rfss->sw_rf_switch),
+				 le32_to_cpu(rfss->hw_rf_switch));
+			i2400m_report_tlv_rf_switches_status(i2400m, rfss);
+		}
+		if (0 == i2400m_tlv_match(tlv, I2400M_TLV_MEDIA_STATUS,
+					  sizeof(*ms))) {
+			ms = container_of(tlv, typeof(*ms), hdr);
+			d_printf(2, dev, "%s: Media Status TLV: %u\n",
+				 tag, le32_to_cpu(ms->media_status));
+			i2400m_report_tlv_media_status(i2400m, ms);
+		}
+	}
+	d_fnend(4, dev, "(i2400m %p, l3l4_hdr %p, size %zu, %s) = void\n",
+		i2400m, l3l4_hdr, size, tag);
+}
+
+
+/*
+ * i2400m_report_hook - (maybe) act on a report
+ *
+ * @i2400m: device descriptor
+ * @l3l4_hdr: pointer to message; it has been already validated for
+ *            consistent size.
+ * @size: size of the message (header + payload). The header length
+ *        declaration is assumed to be congruent with @size (as in
+ *        sizeof(*l3l4_hdr) + l3l4_hdr->length == size)
+ *
+ * Extract information we might need (like carrien on/off) from a
+ * device report.
+ */
+void i2400m_report_hook(struct i2400m *i2400m,
+			const struct i2400m_l3l4_hdr *l3l4_hdr, size_t size)
+{
+	struct device *dev = i2400m_dev(i2400m);
+	unsigned msg_type;
+
+	d_fnstart(3, dev, "(i2400m %p l3l4_hdr %p size %zu)\n",
+		  i2400m, l3l4_hdr, size);
+	/* Chew on the message, we might need some information from
+	 * here */
+	msg_type = le16_to_cpu(l3l4_hdr->type);
+	switch (msg_type) {
+	case I2400M_MT_REPORT_STATE:	/* carrier detection... */
+		i2400m_report_state_hook(i2400m,
+					 l3l4_hdr, size, "REPORT STATE");
+		break;
+	/* If the device is ready for power save, then ask it to do
+	 * it. */
+	case I2400M_MT_REPORT_POWERSAVE_READY:	/* zzzzz */
+		if (l3l4_hdr->status == cpu_to_le16(I2400M_MS_DONE_OK)) {
+			d_printf(1, dev, "ready for powersave, requesting\n");
+			i2400m_cmd_enter_powersave(i2400m);
+		}
+		break;
+	};
+	d_fnend(3, dev, "(i2400m %p l3l4_hdr %p size %zu) = void\n",
+		i2400m, l3l4_hdr, size);
+}
+
+
+/*
+ * i2400m_msg_ack_hook - process cmd/set/get ack for internal status
+ *
+ * @i2400m: device descriptor
+ * @l3l4_hdr: pointer to message; it has been already validated for
+ *            consistent size.
+ * @size: size of the message
+ *
+ * Extract information we might need from acks to commands and act on
+ * it. This is akin to i2400m_report_hook(). Note most of this
+ * processing should be done in the function that calls the
+ * command. This is here for some cases where it can't happen...
+ */
+void i2400m_msg_ack_hook(struct i2400m *i2400m,
+			 const struct i2400m_l3l4_hdr *l3l4_hdr, size_t size)
+{
+	int result;
+	struct device *dev = i2400m_dev(i2400m);
+	unsigned ack_type, ack_status;
+	char strerr[32];
+
+	/* Chew on the message, we might need some information from
+	 * here */
+	ack_type = le16_to_cpu(l3l4_hdr->type);
+	ack_status = le16_to_cpu(l3l4_hdr->status);
+	switch (ack_type) {
+	case I2400M_MT_CMD_ENTER_POWERSAVE:
+		/* This is just left here for the sake of example, as
+		 * the processing is done somewhere else. */
+		if (0) {
+			result = i2400m_msg_check_status(
+				l3l4_hdr, strerr, sizeof(strerr));
+			if (result >= 0)
+				d_printf(1, dev, "ready for power save: %zd\n",
+					 size);
+		}
+		break;
+	};
+	return;
+}
+
+
+/*
+ * i2400m_msg_size_check() - verify message size and header are congruent
+ *
+ * It is ok if the total message size is larger than the expected
+ * size, as there can be padding.
+ */
+int i2400m_msg_size_check(struct i2400m *i2400m,
+			  const struct i2400m_l3l4_hdr *l3l4_hdr,
+			  size_t msg_size)
+{
+	int result;
+	struct device *dev = i2400m_dev(i2400m);
+	size_t expected_size;
+	d_fnstart(4, dev, "(i2400m %p l3l4_hdr %p msg_size %zu)\n",
+		  i2400m, l3l4_hdr, msg_size);
+	if (msg_size < sizeof(*l3l4_hdr)) {
+		dev_err(dev, "bad size for message header "
+			"(expected at least %zu, got %zu)\n",
+			(size_t) sizeof(*l3l4_hdr), msg_size);
+		result = -EIO;
+		goto error_hdr_size;
+	}
+	expected_size = le16_to_cpu(l3l4_hdr->length) + sizeof(*l3l4_hdr);
+	if (msg_size < expected_size) {
+		dev_err(dev, "bad size for message code 0x%04x (expected %zu, "
+			"got %zu)\n", le16_to_cpu(l3l4_hdr->type),
+			expected_size, msg_size);
+		result = -EIO;
+	} else
+		result = 0;
+error_hdr_size:
+	d_fnend(4, dev,
+		"(i2400m %p l3l4_hdr %p msg_size %zu) = %d\n",
+		i2400m, l3l4_hdr, msg_size, result);
+	return result;
+}
+
+
+
+/*
+ * Cancel a wait for a command ACK
+ *
+ * @i2400m: device descriptor
+ * @code: [negative] errno code to cancel with (don't use
+ *     -EINPROGRESS)
+ *
+ * If there is an ack already filled out, free it.
+ */
+void i2400m_msg_to_dev_cancel_wait(struct i2400m *i2400m, int code)
+{
+	struct sk_buff *ack_skb;
+	unsigned long flags;
+
+	spin_lock_irqsave(&i2400m->rx_lock, flags);
+	ack_skb = i2400m->ack_skb;
+	if (ack_skb && !IS_ERR(ack_skb))
+		kfree(ack_skb);
+	i2400m->ack_skb = ERR_PTR(code);
+	spin_unlock_irqrestore(&i2400m->rx_lock, flags);
+}
+
+
+/**
+ * i2400m_msg_to_dev - Send a control message to the device and get a response
+ *
+ * @i2400m: device descriptor
+ *
+ * @msg_skb: an skb  *
+ *
+ * @buf: pointer to the buffer containing the message to be sent; it
+ *           has to start with a &struct i2400M_l3l4_hdr and then
+ *           followed by the payload. Once this function returns, the
+ *           buffer can be reused.
+ *
+ * @buf_len: buffer size
+ *
+ * Returns:
+ *
+ * Pointer to skb containing the ack message. You need to check the
+ * pointer with IS_ERR(), as it might be an error code. Error codes
+ * could happen because:
+ *
+ *  - the message wasn't formatted correctly
+ *  - couldn't send the message
+ *  - failed waiting for a response
+ *  - the ack message wasn't formatted correctly
+ *
+ * The returned skb has been allocated with wimax_msg_to_user_alloc(),
+ * it contains the reponse in a netlink attribute and is ready to be
+ * passed up to user space with wimax_msg_to_user_send(). To access
+ * the payload and its length, use wimax_msg_{data,len}() on the skb.
+ *
+ * The skb has to be freed with kfree_skb() once done.
+ *
+ * Description:
+ *
+ * This function delivers a message/command to the device and waits
+ * for an ack to be received. The format is described in
+ * linux/wimax/i2400m.h. In summary, a command/get/set is followed by an
+ * ack.
+ *
+ * This function will not check the ack status, that's left up to the
+ * caller.  Once done with the ack skb, it has to be kfree_skb()ed.
+ *
+ * The i2400m handles only one message at the same time, thus we need
+ * the mutex to exclude other players.
+ *
+ * We write the message and then wait for an answer to come back. The
+ * RX path intercepts control messages and handles them in
+ * i2400m_rx_ctl(). Reports (notifications) are (maybe) processed
+ * locally and then forwarded (as needed) to user space on the WiMAX
+ * stack message pipe. Acks are saved and passed back to us through an
+ * skb in i2400m->ack_skb which is ready to be given to generic
+ * netlink if need be.
+ */
+struct sk_buff *i2400m_msg_to_dev(struct i2400m *i2400m,
+				  const void *buf, size_t buf_len)
+{
+	int result;
+	struct device *dev = i2400m_dev(i2400m);
+	const struct i2400m_l3l4_hdr *msg_l3l4_hdr;
+	struct sk_buff *ack_skb;
+	const struct i2400m_l3l4_hdr *ack_l3l4_hdr;
+	size_t ack_len;
+	int ack_timeout;
+	unsigned msg_type;
+	unsigned long flags;
+
+	d_fnstart(3, dev, "(i2400m %p buf %p len %zu)\n",
+		  i2400m, buf, buf_len);
+
+	if (i2400m->boot_mode)
+		return ERR_PTR(-ENODEV);
+
+	msg_l3l4_hdr = buf;
+	/* Check msg & payload consistency */
+	result = i2400m_msg_size_check(i2400m, msg_l3l4_hdr, buf_len);
+	if (result < 0)
+		goto error_bad_msg;
+	msg_type = le16_to_cpu(msg_l3l4_hdr->type);
+	d_printf(1, dev, "CMD/GET/SET 0x%04x %zu bytes\n",
+		 msg_type, buf_len);
+	d_dump(2, dev, buf, buf_len);
+
+	/* Setup the completion, ack_skb ("we are waiting") and send
+	 * the message to the device */
+	mutex_lock(&i2400m->msg_mutex);
+	spin_lock_irqsave(&i2400m->rx_lock, flags);
+	i2400m->ack_skb = ERR_PTR(-EINPROGRESS);
+	spin_unlock_irqrestore(&i2400m->rx_lock, flags);
+	init_completion(&i2400m->msg_completion);
+	result = i2400m_tx(i2400m, buf, buf_len, I2400M_PT_CTRL);
+	if (result < 0) {
+		dev_err(dev, "can't send message 0x%04x: %d\n",
+			le16_to_cpu(msg_l3l4_hdr->type), result);
+		goto error_tx;
+	}
+
+	/* Some commands take longer to execute because of crypto ops,
+	 * so we give them some more leeway on timeout */
+	switch (msg_type) {
+	case I2400M_MT_GET_TLS_OPERATION_RESULT:
+	case I2400M_MT_CMD_SEND_EAP_RESPONSE:
+		ack_timeout = 5 * HZ;
+		break;
+	default:
+		ack_timeout = HZ;
+	};
+
+	/* The RX path in rx.c will put any response for this message
+	 * in i2400m->ack_skb and wake us up. If we cancel the wait,
+	 * we need to change the value of i2400m->ack_skb to something
+	 * not -EINPROGRESS so RX knows there is no one waiting. */
+	result = wait_for_completion_interruptible_timeout(
+		&i2400m->msg_completion, ack_timeout);
+	if (result == 0) {
+		dev_err(dev, "timeout waiting for reply to message 0x%04x\n",
+			msg_type);
+		result = -ETIMEDOUT;
+		i2400m_msg_to_dev_cancel_wait(i2400m, result);
+		goto error_wait_for_completion;
+	} else if (result < 0) {
+		dev_err(dev, "error waiting for reply to message 0x%04x: %d\n",
+			msg_type, result);
+		i2400m_msg_to_dev_cancel_wait(i2400m, result);
+		goto error_wait_for_completion;
+	}
+
+	/* Pull out the ack data from i2400m->ack_skb -- see if it is
+	 * an error and act accordingly */
+	spin_lock_irqsave(&i2400m->rx_lock, flags);
+	ack_skb = i2400m->ack_skb;
+	if (IS_ERR(ack_skb))
+		result = PTR_ERR(ack_skb);
+	else
+		result = 0;
+	i2400m->ack_skb = NULL;
+	spin_unlock_irqrestore(&i2400m->rx_lock, flags);
+	if (result < 0)
+		goto error_ack_status;
+	ack_l3l4_hdr = wimax_msg_data_len(ack_skb, &ack_len);
+
+	/* Check the ack and deliver it if it is ok */
+	result = i2400m_msg_size_check(i2400m, ack_l3l4_hdr, ack_len);
+	if (result < 0) {
+		dev_err(dev, "HW BUG? reply to message 0x%04x: %d\n",
+			msg_type, result);
+		goto error_bad_ack_len;
+	}
+	if (msg_type != le16_to_cpu(ack_l3l4_hdr->type)) {
+		dev_err(dev, "HW BUG? bad reply 0x%04x to message 0x%04x\n",
+			le16_to_cpu(ack_l3l4_hdr->type), msg_type);
+		result = -EIO;
+		goto error_bad_ack_type;
+	}
+	i2400m_msg_ack_hook(i2400m, ack_l3l4_hdr, ack_len);
+	mutex_unlock(&i2400m->msg_mutex);
+	d_fnend(3, dev, "(i2400m %p buf %p len %zu) = %p\n",
+		i2400m, buf, buf_len, ack_skb);
+	return ack_skb;
+
+error_bad_ack_type:
+error_bad_ack_len:
+	kfree_skb(ack_skb);
+error_ack_status:
+error_wait_for_completion:
+error_tx:
+	mutex_unlock(&i2400m->msg_mutex);
+error_bad_msg:
+	d_fnend(3, dev, "(i2400m %p buf %p len %zu) = %d\n",
+		i2400m, buf, buf_len, result);
+	return ERR_PTR(result);
+}
+
+
+/*
+ * Definitions for the Enter Power Save command
+ *
+ * The Enter Power Save command requests the device to go into power
+ * saving mode. The device will ack or nak the command depending on it
+ * being ready for it. If it acks, we tell the USB subsystem to
+ *
+ * As well, the device might request to go into power saving mode by
+ * sending a report (REPORT_POWERSAVE_READY), in which case, we issue
+ * this command. The hookups in the RX coder allow
+ */
+enum {
+	I2400M_WAKEUP_ENABLED  = 0x01,
+	I2400M_WAKEUP_DISABLED = 0x02,
+	I2400M_TLV_TYPE_WAKEUP_MODE = 144,
+};
+
+struct i2400m_cmd_enter_power_save {
+	struct i2400m_l3l4_hdr hdr;
+	struct i2400m_tlv_hdr tlv;
+	__le32 val;
+} __attribute__((packed));
+
+
+/*
+ * Request entering power save
+ *
+ * This command is (mainly) executed when the device indicates that it
+ * is ready to go into powersave mode via a REPORT_POWERSAVE_READY.
+ */
+int i2400m_cmd_enter_powersave(struct i2400m *i2400m)
+{
+	int result;
+	struct device *dev = i2400m_dev(i2400m);
+	struct sk_buff *ack_skb;
+	struct i2400m_cmd_enter_power_save *cmd;
+	char strerr[32];
+
+	result = -ENOMEM;
+	cmd = kzalloc(sizeof(*cmd), GFP_KERNEL);
+	if (cmd == NULL)
+		goto error_alloc;
+	cmd->hdr.type = cpu_to_le16(I2400M_MT_CMD_ENTER_POWERSAVE);
+	cmd->hdr.length = cpu_to_le16(sizeof(*cmd) - sizeof(cmd->hdr));
+	cmd->hdr.version = cpu_to_le16(I2400M_L3L4_VERSION);
+	cmd->tlv.type = cpu_to_le16(I2400M_TLV_TYPE_WAKEUP_MODE);
+	cmd->tlv.length = cpu_to_le16(sizeof(cmd->val));
+	cmd->val = cpu_to_le32(I2400M_WAKEUP_ENABLED);
+
+	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 'Enter power save' command: %d\n",
+			result);
+		goto error_msg_to_dev;
+	}
+	result = i2400m_msg_check_status(wimax_msg_data(ack_skb),
+					 strerr, sizeof(strerr));
+	if (result == -EACCES)
+		d_printf(1, dev, "Cannot enter power save mode\n");
+	else if (result < 0)
+		dev_err(dev, "'Enter power save' (0x%04x) command failed: "
+			"%d - %s\n", I2400M_MT_CMD_ENTER_POWERSAVE,
+			result, strerr);
+	else
+		d_printf(1, dev, "device ready to power save\n");
+	kfree_skb(ack_skb);
+error_msg_to_dev:
+	kfree(cmd);
+error_alloc:
+	return result;
+}
+EXPORT_SYMBOL_GPL(i2400m_cmd_enter_powersave);
+
+
+/*
+ * Definitions for getting device information
+ */
+enum {
+	I2400M_TLV_DETAILED_DEVICE_INFO = 140
+};
+
+/**
+ * i2400m_get_device_info - Query the device for detailed device information
+ *
+ * @i2400m: device descriptor
+ *
+ * Returns: an skb whose skb->data points to a 'struct
+ *    i2400m_tlv_detailed_device_info'. When done, kfree_skb() it. The
+ *    skb is *guaranteed* to contain the whole TLV data structure.
+ *
+ *    On error, IS_ERR(skb) is true and ERR_PTR(skb) is the error
+ *    code.
+ */
+struct sk_buff *i2400m_get_device_info(struct i2400m *i2400m)
+{
+	int result;
+	struct device *dev = i2400m_dev(i2400m);
+	struct sk_buff *ack_skb;
+	struct i2400m_l3l4_hdr *cmd;
+	const struct i2400m_l3l4_hdr *ack;
+	size_t ack_len;
+	const struct i2400m_tlv_hdr *tlv;
+	const struct i2400m_tlv_detailed_device_info *ddi;
+	char strerr[32];
+
+	ack_skb = ERR_PTR(-ENOMEM);
+	cmd = kzalloc(sizeof(*cmd), GFP_KERNEL);
+	if (cmd == NULL)
+		goto error_alloc;
+	cmd->type = cpu_to_le16(I2400M_MT_GET_DEVICE_INFO);
+	cmd->length = 0;
+	cmd->version = cpu_to_le16(I2400M_L3L4_VERSION);
+
+	ack_skb = i2400m_msg_to_dev(i2400m, cmd, sizeof(*cmd));
+	if (IS_ERR(ack_skb)) {
+		dev_err(dev, "Failed to issue 'get device info' command: %ld\n",
+			PTR_ERR(ack_skb));
+		goto error_msg_to_dev;
+	}
+	ack = wimax_msg_data_len(ack_skb, &ack_len);
+	result = i2400m_msg_check_status(ack, strerr, sizeof(strerr));
+	if (result < 0) {
+		dev_err(dev, "'get device info' (0x%04x) command failed: "
+			"%d - %s\n", I2400M_MT_GET_DEVICE_INFO, result,
+			strerr);
+		goto error_cmd_failed;
+	}
+	tlv = i2400m_tlv_find(i2400m, ack->pl, ack_len - sizeof(*ack),
+			      I2400M_TLV_DETAILED_DEVICE_INFO, sizeof(*ddi));
+	if (tlv == NULL) {
+		dev_err(dev, "GET DEVICE INFO: "
+			"detailed device info TLV not found (0x%04x)\n",
+			I2400M_TLV_DETAILED_DEVICE_INFO);
+		result = -EIO;
+		goto error_no_tlv;
+	}
+	skb_pull(ack_skb, (void *) tlv - (void *) ack_skb->data);
+error_msg_to_dev:
+	kfree(cmd);
+error_alloc:
+	return ack_skb;
+
+error_no_tlv:
+error_cmd_failed:
+	kfree_skb(ack_skb);
+	kfree(cmd);
+	return ERR_PTR(result);
+}
+
+
+/* Firmware interface versions we support */
+enum {
+	I2400M_HDIv_MAJOR = 9,
+	I2400M_HDIv_MAJOR_2 = 8,
+	I2400M_HDIv_MINOR = 1,
+};
+
+
+/**
+ * i2400m_firmware_check - check firmware versions are compatible with
+ * the driver
+ *
+ * @i2400m: device descriptor
+ *
+ * Returns: 0 if ok, < 0 errno code an error and a message in the
+ *    kernel log.
+ *
+ * Long function, but quite simple; first chunk launches the command
+ * and double checks the reply for the right TLV. Then we process the
+ * TLV (where the meat is).
+ */
+int i2400m_firmware_check(struct i2400m *i2400m)
+{
+	int result;
+	struct device *dev = i2400m_dev(i2400m);
+	struct sk_buff *ack_skb;
+	struct i2400m_l3l4_hdr *cmd;
+	const struct i2400m_l3l4_hdr *ack;
+	size_t ack_len;
+	const struct i2400m_tlv_hdr *tlv;
+	const struct i2400m_tlv_l4_message_versions *l4mv;
+	char strerr[32];
+	unsigned major, minor, branch;
+
+	result = -ENOMEM;
+	cmd = kzalloc(sizeof(*cmd), GFP_KERNEL);
+	if (cmd == NULL)
+		goto error_alloc;
+	cmd->type = cpu_to_le16(I2400M_MT_GET_LM_VERSION);
+	cmd->length = 0;
+	cmd->version = cpu_to_le16(I2400M_L3L4_VERSION);
+
+	ack_skb = i2400m_msg_to_dev(i2400m, cmd, sizeof(*cmd));
+	if (IS_ERR(ack_skb)) {
+		result = PTR_ERR(ack_skb);
+		dev_err(dev, "Failed to issue 'get lm version' command: %-d\n",
+			result);
+		goto error_msg_to_dev;
+	}
+	ack = wimax_msg_data_len(ack_skb, &ack_len);
+	result = i2400m_msg_check_status(ack, strerr, sizeof(strerr));
+	if (result < 0) {
+		dev_err(dev, "'get lm version' (0x%04x) command failed: "
+			"%d - %s\n", I2400M_MT_GET_LM_VERSION, result,
+			strerr);
+		goto error_cmd_failed;
+	}
+	tlv = i2400m_tlv_find(i2400m, ack->pl, ack_len - sizeof(*ack),
+			      I2400M_TLV_L4_MESSAGE_VERSIONS, sizeof(*l4mv));
+	if (tlv == NULL) {
+		dev_err(dev, "get lm version: TLV not found (0x%04x)\n",
+			I2400M_TLV_L4_MESSAGE_VERSIONS);
+		result = -EIO;
+		goto error_no_tlv;
+	}
+	l4mv = container_of(tlv, typeof(*l4mv), hdr);
+	major = le16_to_cpu(l4mv->major);
+	minor = le16_to_cpu(l4mv->minor);
+	branch = le16_to_cpu(l4mv->branch);
+	result = -EINVAL;
+	if (major != I2400M_HDIv_MAJOR
+	    && major != I2400M_HDIv_MAJOR_2) {
+		dev_err(dev, "unsupported major fw interface version "
+			"%u.%u.%u\n", major, minor, branch);
+		goto error_bad_major;
+	}
+	if (major == I2400M_HDIv_MAJOR_2)
+		dev_err(dev, "deprecated major fw interface version "
+			"%u.%u.%u\n", major, minor, branch);
+	result = 0;
+	if (minor != I2400M_HDIv_MINOR)
+		dev_warn(dev, "untested minor fw firmware version %u.%u.%u\n",
+			 major, minor, branch);
+error_bad_major:
+	dev_info(dev, "firmware interface version %u.%u.%u\n",
+		 major, minor, branch);
+error_no_tlv:
+error_cmd_failed:
+	kfree_skb(ack_skb);
+error_msg_to_dev:
+	kfree(cmd);
+error_alloc:
+	return result;
+}
+
+
+/*
+ * Send an DoExitIdle command to the device to ask it to go out of
+ * basestation-idle mode.
+ *
+ * @i2400m: device descriptor
+ *
+ * This starts a renegotiation with the basestation that might involve
+ * another crypto handshake with user space.
+ *
+ * Returns: 0 if ok, < 0 errno code on error.
+ */
+int i2400m_cmd_exit_idle(struct i2400m *i2400m)
+{
+	int result;
+	struct device *dev = i2400m_dev(i2400m);
+	struct sk_buff *ack_skb;
+	struct i2400m_l3l4_hdr *cmd;
+	char strerr[32];
+
+	result = -ENOMEM;
+	cmd = kzalloc(sizeof(*cmd), GFP_KERNEL);
+	if (cmd == NULL)
+		goto error_alloc;
+	cmd->type = cpu_to_le16(I2400M_MT_CMD_EXIT_IDLE);
+	cmd->length = 0;
+	cmd->version = cpu_to_le16(I2400M_L3L4_VERSION);
+
+	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 'exit idle' command: %d\n",
+			result);
+		goto error_msg_to_dev;
+	}
+	result = i2400m_msg_check_status(wimax_msg_data(ack_skb),
+					 strerr, sizeof(strerr));
+	kfree_skb(ack_skb);
+error_msg_to_dev:
+	kfree(cmd);
+error_alloc:
+	return result;
+
+}
+
+
+/*
+ * Query the device for its state, update the WiMAX stack's idea of it
+ *
+ * @i2400m: device descriptor
+ *
+ * Returns: 0 if ok, < 0 errno code on error.
+ *
+ * Executes a 'Get State' command and parses the returned
+ * TLVs.
+ *
+ * Because this is almost identical to a 'Report State', we use
+ * i2400m_report_state_hook() to parse the answer. This will set the
+ * carrier state, as well as the RF Kill switches state.
+ */
+int i2400m_cmd_get_state(struct i2400m *i2400m)
+{
+	int result;
+	struct device *dev = i2400m_dev(i2400m);
+	struct sk_buff *ack_skb;
+	struct i2400m_l3l4_hdr *cmd;
+	const struct i2400m_l3l4_hdr *ack;
+	size_t ack_len;
+	char strerr[32];
+
+	result = -ENOMEM;
+	cmd = kzalloc(sizeof(*cmd), GFP_KERNEL);
+	if (cmd == NULL)
+		goto error_alloc;
+	cmd->type = cpu_to_le16(I2400M_MT_GET_STATE);
+	cmd->length = 0;
+	cmd->version = cpu_to_le16(I2400M_L3L4_VERSION);
+
+	ack_skb = i2400m_msg_to_dev(i2400m, cmd, sizeof(*cmd));
+	if (IS_ERR(ack_skb)) {
+		dev_err(dev, "Failed to issue 'get state' command: %ld\n",
+			PTR_ERR(ack_skb));
+		result = PTR_ERR(ack_skb);
+		goto error_msg_to_dev;
+	}
+	ack = wimax_msg_data_len(ack_skb, &ack_len);
+	result = i2400m_msg_check_status(ack, strerr, sizeof(strerr));
+	if (result < 0) {
+		dev_err(dev, "'get state' (0x%04x) command failed: "
+			"%d - %s\n", I2400M_MT_GET_STATE, result, strerr);
+		goto error_cmd_failed;
+	}
+	i2400m_report_state_hook(i2400m, ack, ack_len - sizeof(*ack),
+				 "GET STATE");
+	result = 0;
+	kfree_skb(ack_skb);
+error_cmd_failed:
+error_msg_to_dev:
+	kfree(cmd);
+error_alloc:
+	return result;
+}
+EXPORT_SYMBOL_GPL(i2400m_cmd_get_state);
+
+
+/**
+ * Set basic configuration settings
+ *
+ * @i2400m: device descriptor
+ * @args: array of pointers to the TLV headers to send for
+ *     configuration (each followed by its payload).
+ *     TLV headers and payloads must be properly initialized, with the
+ *     right endianess (LE).
+ * @arg_size: number of pointers in the @args array
+ */
+int i2400m_set_init_config(struct i2400m *i2400m,
+			   const struct i2400m_tlv_hdr **arg, size_t args)
+{
+	int result;
+	struct device *dev = i2400m_dev(i2400m);
+	struct sk_buff *ack_skb;
+	struct i2400m_l3l4_hdr *cmd;
+	char strerr[32];
+	unsigned argc, argsize, tlv_size;
+	const struct i2400m_tlv_hdr *tlv_hdr;
+	void *buf, *itr;
+
+	d_fnstart(3, dev, "(i2400m %p arg %p args %zu)\n", i2400m, arg, args);
+	result = 0;
+	if (args == 0)
+		goto none;
+	/* Compute the size of all the TLVs, so we can alloc a
+	 * contiguous command block to copy them. */
+	argsize = 0;
+	for (argc = 0; argc < args; argc++) {
+		tlv_hdr = arg[argc];
+		argsize += sizeof(*tlv_hdr) + le16_to_cpu(tlv_hdr->length);
+	}
+	WARN_ON(argc >= 9);	/* As per hw spec */
+
+	/* Alloc the space for the command and TLVs*/
+	result = -ENOMEM;
+	buf = kzalloc(sizeof(*cmd) + argsize, GFP_KERNEL);
+	if (buf == NULL)
+		goto error_alloc;
+	cmd = buf;
+	cmd->type = cpu_to_le16(I2400M_MT_SET_INIT_CONFIG);
+	cmd->length = cpu_to_le16(argsize);
+	cmd->version = cpu_to_le16(I2400M_L3L4_VERSION);
+
+	/* Copy the TLVs */
+	itr = buf + sizeof(*cmd);
+	for (argc = 0; argc < args; argc++) {
+		tlv_hdr = arg[argc];
+		tlv_size = sizeof(*tlv_hdr) + le16_to_cpu(tlv_hdr->length);
+		memcpy(itr, tlv_hdr, tlv_size);
+		itr += tlv_size;
+	}
+
+	/* Send the message! */
+	ack_skb = i2400m_msg_to_dev(i2400m, buf, sizeof(*cmd) + argsize);
+	result = PTR_ERR(ack_skb);
+	if (IS_ERR(ack_skb)) {
+		dev_err(dev, "Failed to issue 'init config' 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, "'init config' (0x%04x) command failed: %d - %s\n",
+			I2400M_MT_SET_INIT_CONFIG, result, strerr);
+	kfree_skb(ack_skb);
+error_msg_to_dev:
+	kfree(buf);
+error_alloc:
+none:
+	d_fnend(3, dev, "(i2400m %p arg %p args %zu) = %d\n",
+		i2400m, arg, args, result);
+	return result;
+
+}
+EXPORT_SYMBOL_GPL(i2400m_set_init_config);
+
+
+/**
+ * i2400m_dev_initialize - Initialize the device once communications are ready
+ *
+ * @i2400m: device descriptor
+ *
+ * Returns: 0 if ok, < 0 errno code on error.
+ *
+ * Configures the device to work the way we like it.
+ *
+ * At the point of this call, the device is registered with the WiMAX
+ * and netdev stacks, firmware is uploaded and we can talk to the
+ * device normally.
+ */
+int i2400m_dev_initialize(struct i2400m *i2400m)
+{
+	int result;
+	struct device *dev = i2400m_dev(i2400m);
+	struct i2400m_tlv_config_idle_parameters idle_params;
+	const struct i2400m_tlv_hdr *args[9];
+	unsigned argc = 0;
+
+	d_fnstart(3, dev, "(i2400m %p)\n", i2400m);
+	/* Useless for now...might change */
+	if (i2400m_idle_mode_disabled) {
+		idle_params.hdr.type =
+			cpu_to_le16(I2400M_TLV_CONFIG_IDLE_PARAMETERS);
+		idle_params.hdr.length = cpu_to_le16(
+			sizeof(idle_params) - sizeof(idle_params.hdr));
+		idle_params.idle_timeout = 0;
+		idle_params.idle_paging_interval = 0;
+		args[argc++] = &idle_params.hdr;
+	}
+	result = i2400m_set_init_config(i2400m, args, argc);
+	if (result < 0)
+		goto error;
+	result = i2400m_firmware_check(i2400m);	/* fw versions ok? */
+	if (result < 0)
+		goto error;
+	/*
+	 * Update state: Here it just calls a get state; parsing the
+	 * result (System State TLV and RF Status TLV [done in the rx
+	 * path hooks]) will set the hardware and software RF-Kill
+	 * status.
+	 */
+	result = i2400m_cmd_get_state(i2400m);
+error:
+	d_fnend(3, dev, "(i2400m %p) = %d\n", i2400m, result);
+	return result;
+}
+
+
+/**
+ * i2400m_dev_shutdown - Shutdown a running device
+ *
+ * @i2400m: device descriptor
+ *
+ * Gracefully stops the device, moving it to the lowest power
+ * consumption state possible.
+ */
+void i2400m_dev_shutdown(struct i2400m *i2400m)
+{
+	int result = -ENODEV;
+	struct device *dev = i2400m_dev(i2400m);
+
+	d_fnstart(3, dev, "(i2400m %p)\n", i2400m);
+	result = i2400m->bus_reset(i2400m, I2400M_RT_WARM);
+	d_fnend(3, dev, "(i2400m %p) = void [%d]\n", i2400m, result);
+	return;
+}
-- 
1.5.6.5