diff options
Diffstat (limited to 'kernel/drivers/uwb/reset.c')
| -rw-r--r-- | kernel/drivers/uwb/reset.c | 393 |
1 files changed, 393 insertions, 0 deletions
diff --git a/kernel/drivers/uwb/reset.c b/kernel/drivers/uwb/reset.c new file mode 100644 index 000000000..8b47c9cdd --- /dev/null +++ b/kernel/drivers/uwb/reset.c @@ -0,0 +1,393 @@ +/* + * 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 <linux/slab.h> +#include <linux/delay.h> +#include <linux/export.h> + +#include "uwb-internal.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 received", + "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); + uwb_dev_unlock(&rc->uwb_dev); + 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(¶ms.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, ¶ms); + if (result) + return result; + + wait_for_completion(¶ms.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; + + dev_info(&rc->uwb_dev.dev, "resetting radio controller\n"); + ret = rc->reset(rc); + if (ret < 0) { + dev_err(&rc->uwb_dev.dev, "failed to reset hardware: %d\n", ret); + goto error; + } + return 0; +error: + /* Nothing can be done except try the reset again. Wait a bit + to avoid reset loops during probe() or remove(). */ + msleep(1000); + uwb_rc_reset_all(rc); + 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); + +void uwb_rc_pre_reset(struct uwb_rc *rc) +{ + rc->stop(rc); + uwbd_flush(rc); + + uwb_radio_reset_state(rc); + uwb_rsv_remove_all(rc); +} +EXPORT_SYMBOL_GPL(uwb_rc_pre_reset); + +int uwb_rc_post_reset(struct uwb_rc *rc) +{ + int ret; + + ret = rc->start(rc); + if (ret) + goto out; + ret = uwb_rc_mac_addr_set(rc, &rc->uwb_dev.mac_addr); + if (ret) + goto out; + ret = uwb_rc_dev_addr_set(rc, &rc->uwb_dev.dev_addr); + if (ret) + goto out; +out: + return ret; +} +EXPORT_SYMBOL_GPL(uwb_rc_post_reset); |