uwb: add the UWB stack (radio controller interface)

Add the UWB radio controller interface (URCI) support.

Signed-off-by: David Vrabel <david.vrabel@csr.com>

1 files changed, 362 insertions, 0 deletions

diff --git a/drivers/uwb/reset.c b/drivers/uwb/reset.c
new file mode 100644
index 0000000..8de856f
--- /dev/null
+++ b/drivers/uwb/reset.c
@@ -0,0 +1,362 @@
+/*
+ * Ultra Wide Band
+ * UWB basic command support and radio reset
+ *
+ * Copyright (C) 2005-2006 Intel Corporation
+ * 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.
+ *
+ *
+ * FIXME:
+ *
+ *  - docs
+ *
+ *  - Now we are serializing (using the uwb_dev->mutex) the command
+ *    execution; it should be parallelized as much as possible some
+ *    day.
+ */
+#include <linux/kernel.h>
+#include <linux/err.h>
+
+#include "uwb-internal.h"
+#define D_LOCAL 0
+#include <linux/uwb/debug.h>
+
+/**
+ * Command result codes (WUSB1.0[T8-69])
+ */
+static
+const char *__strerror[] = {
+	"success",
+	"failure",
+	"hardware failure",
+	"no more slots",
+	"beacon is too large",
+	"invalid parameter",
+	"unsupported power level",
+	"time out (wa) or invalid ie data (whci)",
+	"beacon size exceeded",
+	"cancelled",
+	"invalid state",
+	"invalid size",
+	"ack not recieved",
+	"no more asie notification",
+};
+
+
+/** Return a string matching the given error code */
+const char *uwb_rc_strerror(unsigned code)
+{
+	if (code == 255)
+		return "time out";
+	if (code >= ARRAY_SIZE(__strerror))
+		return "unknown error";
+	return __strerror[code];
+}
+
+int uwb_rc_cmd_async(struct uwb_rc *rc, const char *cmd_name,
+		     struct uwb_rccb *cmd, size_t cmd_size,
+		     u8 expected_type, u16 expected_event,
+		     uwb_rc_cmd_cb_f cb, void *arg)
+{
+	struct device *dev = &rc->uwb_dev.dev;
+	struct uwb_rc_neh *neh;
+	int needtofree = 0;
+	int result;
+
+	uwb_dev_lock(&rc->uwb_dev);	/* Protect against rc->priv being removed */
+	if (rc->priv == NULL) {
+		uwb_dev_unlock(&rc->uwb_dev);
+		return -ESHUTDOWN;
+	}
+
+	if (rc->filter_cmd) {
+		needtofree = rc->filter_cmd(rc, &cmd, &cmd_size);
+		if (needtofree < 0 && needtofree != -ENOANO) {
+			dev_err(dev, "%s: filter error: %d\n",
+				cmd_name, needtofree);
+			uwb_dev_unlock(&rc->uwb_dev);
+			return needtofree;
+		}
+	}
+
+	neh = uwb_rc_neh_add(rc, cmd, expected_type, expected_event, cb, arg);
+	if (IS_ERR(neh)) {
+		result = PTR_ERR(neh);
+		goto out;
+	}
+
+	result = rc->cmd(rc, cmd, cmd_size);
+	uwb_dev_unlock(&rc->uwb_dev);
+	if (result < 0)
+		uwb_rc_neh_rm(rc, neh);
+	else
+		uwb_rc_neh_arm(rc, neh);
+	uwb_rc_neh_put(neh);
+out:
+	if (needtofree == 1)
+		kfree(cmd);
+	return result < 0 ? result : 0;
+}
+EXPORT_SYMBOL_GPL(uwb_rc_cmd_async);
+
+struct uwb_rc_cmd_done_params {
+	struct completion completion;
+	struct uwb_rceb *reply;
+	ssize_t reply_size;
+};
+
+static void uwb_rc_cmd_done(struct uwb_rc *rc, void *arg,
+			    struct uwb_rceb *reply, ssize_t reply_size)
+{
+	struct uwb_rc_cmd_done_params *p = (struct uwb_rc_cmd_done_params *)arg;
+
+	if (reply_size > 0) {
+		if (p->reply)
+			reply_size = min(p->reply_size, reply_size);
+		else
+			p->reply = kmalloc(reply_size, GFP_ATOMIC);
+
+		if (p->reply)
+			memcpy(p->reply, reply, reply_size);
+		else
+			reply_size = -ENOMEM;
+	}
+	p->reply_size = reply_size;
+	complete(&p->completion);
+}
+
+
+/**
+ * Generic function for issuing commands to the Radio Control Interface
+ *
+ * @rc:       UWB Radio Control descriptor
+ * @cmd_name: Name of the command being issued (for error messages)
+ * @cmd:      Pointer to rccb structure containing the command;
+ *            normally you embed this structure as the first member of
+ *            the full command structure.
+ * @cmd_size: Size of the whole command buffer pointed to by @cmd.
+ * @reply:    Pointer to where to store the reply
+ * @reply_size: @reply's size
+ * @expected_type: Expected type in the return event
+ * @expected_event: Expected event code in the return event
+ * @preply:   Here a pointer to where the event data is received will
+ *            be stored. Once done with the data, free with kfree().
+ *
+ * This function is generic; it works for commands that return a fixed
+ * and known size or for commands that return a variable amount of data.
+ *
+ * If a buffer is provided, that is used, although it could be chopped
+ * to the maximum size of the buffer. If the buffer is NULL, then one
+ * be allocated in *preply with the whole contents of the reply.
+ *
+ * @rc needs to be referenced
+ */
+static
+ssize_t __uwb_rc_cmd(struct uwb_rc *rc, const char *cmd_name,
+		     struct uwb_rccb *cmd, size_t cmd_size,
+		     struct uwb_rceb *reply, size_t reply_size,
+		     u8 expected_type, u16 expected_event,
+		     struct uwb_rceb **preply)
+{
+	ssize_t result = 0;
+	struct device *dev = &rc->uwb_dev.dev;
+	struct uwb_rc_cmd_done_params params;
+
+	init_completion(&params.completion);
+	params.reply = reply;
+	params.reply_size = reply_size;
+
+	result = uwb_rc_cmd_async(rc, cmd_name, cmd, cmd_size,
+				  expected_type, expected_event,
+				  uwb_rc_cmd_done, &params);
+	if (result)
+		return result;
+
+	wait_for_completion(&params.completion);
+
+	if (preply)
+		*preply = params.reply;
+
+	if (params.reply_size < 0)
+		dev_err(dev, "%s: confirmation event 0x%02x/%04x/%02x "
+			"reception failed: %d\n", cmd_name,
+			expected_type, expected_event, cmd->bCommandContext,
+			(int)params.reply_size);
+	return params.reply_size;
+}
+
+
+/**
+ * Generic function for issuing commands to the Radio Control Interface
+ *
+ * @rc:       UWB Radio Control descriptor
+ * @cmd_name: Name of the command being issued (for error messages)
+ * @cmd:      Pointer to rccb structure containing the command;
+ *            normally you embed this structure as the first member of
+ *            the full command structure.
+ * @cmd_size: Size of the whole command buffer pointed to by @cmd.
+ * @reply:    Pointer to the beginning of the confirmation event
+ *            buffer. Normally bigger than an 'struct hwarc_rceb'.
+ *            You need to fill out reply->bEventType and reply->wEvent (in
+ *            cpu order) as the function will use them to verify the
+ *            confirmation event.
+ * @reply_size: Size of the reply buffer
+ *
+ * The function checks that the length returned in the reply is at
+ * least as big as @reply_size; if not, it will be deemed an error and
+ * -EIO returned.
+ *
+ * @rc needs to be referenced
+ */
+ssize_t uwb_rc_cmd(struct uwb_rc *rc, const char *cmd_name,
+		   struct uwb_rccb *cmd, size_t cmd_size,
+		   struct uwb_rceb *reply, size_t reply_size)
+{
+	struct device *dev = &rc->uwb_dev.dev;
+	ssize_t result;
+
+	result = __uwb_rc_cmd(rc, cmd_name,
+			      cmd, cmd_size, reply, reply_size,
+			      reply->bEventType, reply->wEvent, NULL);
+
+	if (result > 0 && result < reply_size) {
+		dev_err(dev, "%s: not enough data returned for decoding reply "
+			"(%zu bytes received vs at least %zu needed)\n",
+			cmd_name, result, reply_size);
+		result = -EIO;
+	}
+	return result;
+}
+EXPORT_SYMBOL_GPL(uwb_rc_cmd);
+
+
+/**
+ * Generic function for issuing commands to the Radio Control
+ * Interface that return an unknown amount of data
+ *
+ * @rc:       UWB Radio Control descriptor
+ * @cmd_name: Name of the command being issued (for error messages)
+ * @cmd:      Pointer to rccb structure containing the command;
+ *            normally you embed this structure as the first member of
+ *            the full command structure.
+ * @cmd_size: Size of the whole command buffer pointed to by @cmd.
+ * @expected_type: Expected type in the return event
+ * @expected_event: Expected event code in the return event
+ * @preply:   Here a pointer to where the event data is received will
+ *            be stored. Once done with the data, free with kfree().
+ *
+ * The function checks that the length returned in the reply is at
+ * least as big as a 'struct uwb_rceb *'; if not, it will be deemed an
+ * error and -EIO returned.
+ *
+ * @rc needs to be referenced
+ */
+ssize_t uwb_rc_vcmd(struct uwb_rc *rc, const char *cmd_name,
+		    struct uwb_rccb *cmd, size_t cmd_size,
+		    u8 expected_type, u16 expected_event,
+		    struct uwb_rceb **preply)
+{
+	return __uwb_rc_cmd(rc, cmd_name, cmd, cmd_size, NULL, 0,
+			    expected_type, expected_event, preply);
+}
+EXPORT_SYMBOL_GPL(uwb_rc_vcmd);
+
+
+/**
+ * Reset a UWB Host Controller (and all radio settings)
+ *
+ * @rc:      Host Controller descriptor
+ * @returns: 0 if ok, < 0 errno code on error
+ *
+ * We put the command on kmalloc'ed memory as some arches cannot do
+ * USB from the stack. The reply event is copied from an stage buffer,
+ * so it can be in the stack. See WUSB1.0[8.6.2.4] for more details.
+ */
+int uwb_rc_reset(struct uwb_rc *rc)
+{
+	int result = -ENOMEM;
+	struct uwb_rc_evt_confirm reply;
+	struct uwb_rccb *cmd;
+	size_t cmd_size = sizeof(*cmd);
+
+	mutex_lock(&rc->uwb_dev.mutex);
+	cmd = kzalloc(sizeof(*cmd), GFP_KERNEL);
+	if (cmd == NULL)
+		goto error_kzalloc;
+	cmd->bCommandType = UWB_RC_CET_GENERAL;
+	cmd->wCommand = cpu_to_le16(UWB_RC_CMD_RESET);
+	reply.rceb.bEventType = UWB_RC_CET_GENERAL;
+	reply.rceb.wEvent = UWB_RC_CMD_RESET;
+	result = uwb_rc_cmd(rc, "RESET", cmd, cmd_size,
+			    &reply.rceb, sizeof(reply));
+	if (result < 0)
+		goto error_cmd;
+	if (reply.bResultCode != UWB_RC_RES_SUCCESS) {
+		dev_err(&rc->uwb_dev.dev,
+			"RESET: command execution failed: %s (%d)\n",
+			uwb_rc_strerror(reply.bResultCode), reply.bResultCode);
+		result = -EIO;
+	}
+error_cmd:
+	kfree(cmd);
+error_kzalloc:
+	mutex_unlock(&rc->uwb_dev.mutex);
+	return result;
+}
+
+int uwbd_msg_handle_reset(struct uwb_event *evt)
+{
+	struct uwb_rc *rc = evt->rc;
+	int ret;
+
+	/* Need to prevent the RC hardware module going away while in
+	   the rc->reset() call. */
+	if (!try_module_get(rc->owner))
+		return 0;
+
+	dev_info(&rc->uwb_dev.dev, "resetting radio controller\n");
+	ret = rc->reset(rc);
+	if (ret)
+		dev_err(&rc->uwb_dev.dev, "failed to reset hardware: %d\n", ret);
+
+	module_put(rc->owner);
+	return ret;
+}
+
+/**
+ * uwb_rc_reset_all - request a reset of the radio controller and PALs
+ * @rc: the radio controller of the hardware device to be reset.
+ *
+ * The full hardware reset of the radio controller and all the PALs
+ * will be scheduled.
+ */
+void uwb_rc_reset_all(struct uwb_rc *rc)
+{
+	struct uwb_event *evt;
+
+	evt = kzalloc(sizeof(struct uwb_event), GFP_ATOMIC);
+	if (unlikely(evt == NULL))
+		return;
+
+	evt->rc = __uwb_rc_get(rc);	/* will be put by uwbd's uwbd_event_handle() */
+	evt->ts_jiffies = jiffies;
+	evt->type = UWB_EVT_TYPE_MSG;
+	evt->message = UWB_EVT_MSG_RESET;
+
+	uwbd_event_queue(evt);
+}
+EXPORT_SYMBOL_GPL(uwb_rc_reset_all);