/**************************************************************************** * wireless/ieee802154/mac802154_device.c * * Copyright (C) 2017 Verge Inc. All rights reserved. * Author: Anthony Merlino * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. 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. * 3. Neither the name NuttX 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. * ****************************************************************************/ /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include #include #include #include #include #include #include #include #include #include "mac802154.h" /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ /* Device naming ************************************************************/ #define DEVNAME_FMT "/dev/ieee%d" #define DEVNAME_FMTLEN (9 + 3 + 1) /**************************************************************************** * Private Types ****************************************************************************/ struct mac802154dev_notify_s { uint8_t mn_signo; /* Signal number to use in the notification */ }; /* This structure describes the state of one open mac driver instance */ struct mac802154dev_open_s { /* Supports a singly linked list */ FAR struct mac802154dev_open_s *md_flink; /* The following will be true if we are closing */ volatile bool md_closing; }; struct mac802154dev_dwait_s { uint8_t mw_handle; /* The msdu handle identifying the frame */ sem_t mw_sem; /* The semaphore used to signal the completion */ int mw_status; /* The success/error of the transaction */ /* Supports a singly linked list */ FAR struct mac802154dev_dwait_s *mw_flink; }; struct mac802154dev_callback_s { /* This holds the information visible to the MAC layer */ struct ieee802154_maccb_s mc_cb; /* Interface understood by the MAC layer */ FAR struct mac802154_chardevice_s *mc_priv; /* Our priv data */ }; struct mac802154_chardevice_s { MACHANDLE md_mac; /* Saved binding to the mac layer */ struct mac802154dev_callback_s md_cb; /* Callback information */ sem_t md_exclsem; /* Exclusive device access */ /* The following is a singly linked list of open references to the * MAC device. */ FAR struct mac802154dev_open_s *md_open; FAR struct mac802154dev_dwait_s *md_dwait; #ifndef CONFIG_DISABLE_SIGNALS /* MCPS Service notification information */ struct mac802154dev_notify_s md_mcps_notify; pid_t md_mcps_pid; /* MLME Service notification information */ struct mac802154dev_notify_s md_mlme_notify; pid_t md_mlme_pid; #endif }; /**************************************************************************** * Private Function Prototypes ****************************************************************************/ /* Semaphore helpers */ static inline int mac802154dev_takesem(sem_t *sem); #define mac802154dev_givesem(s) sem_post(s); static void mac802154dev_mlme_notify(FAR const struct ieee802154_maccb_s *maccb, enum ieee802154_macnotify_e notif, FAR const union ieee802154_mlme_notify_u *arg); static void mac802154dev_mcps_notify(FAR const struct ieee802154_maccb_s *maccb, enum ieee802154_macnotify_e notif, FAR const union ieee802154_mcps_notify_u *arg); static int mac802154dev_open(FAR struct file *filep); static int mac802154dev_close(FAR struct file *filep); static ssize_t mac802154dev_read(FAR struct file *filep, FAR char *buffer, size_t len); static ssize_t mac802154dev_write(FAR struct file *filep, FAR const char *buffer, size_t len); static int mac802154dev_ioctl(FAR struct file *filep, int cmd, unsigned long arg); /* MAC callback helpers */ static void mac802154dev_conf_data(FAR struct mac802154_chardevice_s *dev, FAR const struct ieee802154_data_conf_s *conf); /**************************************************************************** * Private Data ****************************************************************************/ static const struct file_operations mac802154dev_fops = { mac802154dev_open , /* open */ mac802154dev_close, /* close */ mac802154dev_read , /* read */ mac802154dev_write, /* write */ NULL, /* seek */ mac802154dev_ioctl /* ioctl */ #ifndef CONFIG_DISABLE_POLL , NULL /* poll */ #endif #ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS , NULL /* unlink */ #endif }; /**************************************************************************** * Private Functions ****************************************************************************/ /**************************************************************************** * Name: mac802154dev_semtake * * Description: * Acquire the semaphore used for access serialization. * ****************************************************************************/ static inline int mac802154dev_takesem(sem_t *sem) { /* Take a count from the semaphore, possibly waiting */ if (sem_wait(sem) < 0) { /* EINTR is the only error that we expect */ int errcode = get_errno(); DEBUGASSERT(errcode == EINTR); return -errcode; } return OK; } /**************************************************************************** * Name: mac802154dev_open * * Description: * Open the 802.15.4 MAC character device. * ****************************************************************************/ static int mac802154dev_open(FAR struct file *filep) { FAR struct inode *inode; FAR struct mac802154_chardevice_s *dev; FAR struct mac802154dev_open_s *opriv; int ret; DEBUGASSERT(filep != NULL && filep->f_inode != NULL); inode = filep->f_inode; dev = inode->i_private; DEBUGASSERT(dev != NULL); /* Get exclusive access to the MAC driver data structure */ ret = mac802154dev_takesem(&dev->md_exclsem); if (ret < 0) { wlerr("ERROR: mac802154dev_takesem failed: %d\n", ret); return ret; } /* Allocate a new open struct */ opriv = (FAR struct mac802154dev_open_s *) kmm_zalloc(sizeof(struct mac802154dev_open_s)); if (!opriv) { wlerr("ERROR: Failed to allocate new open struct\n"); ret = -ENOMEM; goto errout_with_sem; } /* Attach the open struct to the device */ opriv->md_flink = dev->md_open; dev->md_open = opriv; /* Attach the open struct to the file structure */ filep->f_priv = (FAR void *)opriv; ret = OK; errout_with_sem: mac802154dev_givesem(&dev->md_exclsem); return ret; } /**************************************************************************** * Name: mac802154dev_close * * Description: * Close the 802.15.4 MAC character device. * ****************************************************************************/ static int mac802154dev_close(FAR struct file *filep) { FAR struct inode *inode; FAR struct mac802154_chardevice_s *dev; FAR struct mac802154dev_open_s *opriv; FAR struct mac802154dev_open_s *curr; FAR struct mac802154dev_open_s *prev; irqstate_t flags; bool closing; int ret; DEBUGASSERT(filep && filep->f_priv && filep->f_inode); opriv = filep->f_priv; inode = filep->f_inode; DEBUGASSERT(inode->i_private); dev = (FAR struct mac802154_chardevice_s *)inode->i_private; /* Handle an improbable race conditions with the following atomic test * and set. * * This is actually a pretty feeble attempt to handle this. The * improbable race condition occurs if two different threads try to * close the joystick driver at the same time. The rule: don't do * that! It is feeble because we do not really enforce stale pointer * detection anyway. */ flags = enter_critical_section(); closing = opriv->md_closing; opriv->md_closing = true; leave_critical_section(flags); if (closing) { /* Another thread is doing the close */ return OK; } /* Get exclusive access to the driver structure */ ret = mac802154dev_takesem(&dev->md_exclsem); if (ret < 0) { wlerr("ERROR: mac802154_takesem failed: %d\n", ret); return ret; } /* Find the open structure in the list of open structures for the device */ for (prev = NULL, curr = dev->md_open; curr && curr != opriv; prev = curr, curr = curr->md_flink); DEBUGASSERT(curr); if (!curr) { wlerr("ERROR: Failed to find open entry\n"); ret = -ENOENT; goto errout_with_exclsem; } /* Remove the structure from the device */ if (prev) { prev->md_flink = opriv->md_flink; } else { dev->md_open = opriv->md_flink; } /* And free the open structure */ kmm_free(opriv); ret = OK; errout_with_exclsem: mac802154dev_givesem(&dev->md_exclsem); return ret; } /**************************************************************************** * Name: mac802154dev_read * * Description: * Return the last received packet. * ****************************************************************************/ static ssize_t mac802154dev_read(FAR struct file *filep, FAR char *buffer, size_t len) { FAR struct inode *inode; FAR struct mac802154_chardevice_s *dev; int ret; DEBUGASSERT(filep && filep->f_inode); inode = filep->f_inode; DEBUGASSERT(inode->i_private); dev = (FAR struct mac802154_chardevice_s *)inode->i_private; /* Check to make sure that the buffer is big enough to hold at least one * packet. */ if ((len >= SIZEOF_IEEE802154_DATA_REQ_S(1)) && (len <= SIZEOF_IEEE802154_DATA_REQ_S(IEEE802154_MAX_MAC_PAYLOAD_SIZE))) { wlerr("ERROR: buffer too small: %lu\n", (unsigned long)len); return -EINVAL; } /* Get exclusive access to the driver structure */ ret = mac802154dev_takesem(&dev->md_exclsem); if (ret < 0) { wlerr("ERROR: mac802154dev_takesem failed: %d\n", ret); return ret; } /* TODO: Add code to read a packet and return it */ ret = -ENOTSUP; mac802154dev_givesem(&dev->md_exclsem); return ret; } /**************************************************************************** * Name: mac802154dev_write * * Description: * Send a packet over the IEEE802.15.4 network. * ****************************************************************************/ static ssize_t mac802154dev_write(FAR struct file *filep, FAR const char *buffer, size_t len) { FAR struct inode *inode; FAR struct mac802154_chardevice_s *dev; FAR struct ieee802154_data_req_s *req; struct mac802154dev_dwait_s dwait; int ret; DEBUGASSERT(filep && filep->f_inode); inode = filep->f_inode; DEBUGASSERT(inode->i_private); dev = (FAR struct mac802154_chardevice_s *)inode->i_private; /* Check to make sure that the buffer is big enough to hold at least one * packet. */ if ((len >= SIZEOF_IEEE802154_DATA_REQ_S(1)) && (len <= SIZEOF_IEEE802154_DATA_REQ_S(IEEE802154_MAX_MAC_PAYLOAD_SIZE))) { wlerr("ERROR: buffer isn't an ieee802154_data_req_s: %lu\n", (unsigned long)len); return -EINVAL; } DEBUGASSERT(buffer != NULL); req = (FAR struct ieee802154_data_req_s *)buffer; /* If this is a blocking operation, we need to setup a wait struct so we * can unblock when the packet transmission has finished. If this is a * non-blocking write, we pass off the data and then move along. Technically * we stil have to wait for the transaction to get put into the buffer, but we * won't wait for the transaction to actually finish. */ if (!(filep->f_oflags & O_NONBLOCK)) { /* Get exclusive access to the driver structure */ ret = mac802154dev_takesem(&dev->md_exclsem); if (ret < 0) { wlerr("ERROR: mac802154dev_takesem failed: %d\n", ret); return ret; } /* Setup the wait struct */ dwait.mw_handle = req->msdu_handle; /* Link the wait struct */ dwait.mw_flink = dev->md_dwait; dev->md_dwait = &dwait; mac802154dev_givesem(&dev->md_exclsem); } /* Pass the request to the MAC layer */ ret = mac802154_req_data(dev->md_mac, req); if (ret < 0) { wlerr("ERROR: req_data failed %d\n", ret); return ret; } if (!(filep->f_oflags & O_NONBLOCK)) { /* Wait for the DATA.confirm callback to be called for our handle */ if (sem_wait(&dwait.mw_sem) < 0) { /* This should only happen if the wait was canceled by an signal */ DEBUGASSERT(errno == EINTR); return -EINTR; } /* The unlinking of the wait struct happens inside the callback. This * is more efficient since it will already have to find the struct in * the list in order to perform the sem_post. */ return dwait.mw_status; } return OK; } /**************************************************************************** * Name: mac802154dev_ioctl * * Description: * Control the MAC layer via MLME IOCTL commands. * ****************************************************************************/ static int mac802154dev_ioctl(FAR struct file *filep, int cmd, unsigned long arg) { FAR struct inode *inode; FAR struct mac802154_chardevice_s *dev; int ret; DEBUGASSERT(filep != NULL && filep->f_priv != NULL && filep->f_inode != NULL); inode = filep->f_inode; DEBUGASSERT(inode->i_private); dev = (FAR struct mac802154_chardevice_s *)inode->i_private; /* Get exclusive access to the driver structure */ ret = mac802154dev_takesem(&dev->md_exclsem); if (ret < 0) { wlerr("ERROR: mac802154dev_takesem failed: %d\n", ret); return ret; } /* Handle the ioctl command */ switch (cmd) { #ifndef CONFIG_DISABLE_SIGNALS /* Command: MAC802154IOC_MLME_REGISTER, MAC802154IOC_MCPS_REGISTER * Description: Register to receive a signal whenever there is a * event primitive sent from the MAC layer. * Argument: A read-only pointer to an instance of struct * mac802154dev_notify_s * Return: Zero (OK) on success. Minus one will be returned on * failure with the errno value set appropriately. */ case MAC802154IOC_MLME_REGISTER: { FAR struct mac802154dev_notify_s *notify = (FAR struct mac802154dev_notify_s *)((uintptr_t)arg); if (notify) { /* Save the notification events */ dev->md_mlme_notify.mn_signo = notify->mn_signo; dev->md_mlme_pid = getpid(); return OK; } } break; case MAC802154IOC_MCPS_REGISTER: { FAR struct mac802154dev_notify_s *notify = (FAR struct mac802154dev_notify_s *)((uintptr_t)arg); if (notify) { /* Save the notification events */ dev->md_mcps_notify.mn_signo = notify->mn_signo; dev->md_mcps_pid = getpid(); return OK; } } break; #endif case MAC802154IOC_MLME_ASSOC_REQUEST: { FAR struct ieee802154_assoc_req_s *req = (FAR struct ieee802154_assoc_req_s *)((uintptr_t)arg); } break; default: wlerr("ERROR: Unrecognized command %ld\n", cmd); ret = -EINVAL; break; } mac802154dev_givesem(&dev->md_exclsem); return ret; } static void mac802154dev_mlme_notify(FAR const struct ieee802154_maccb_s *maccb, enum ieee802154_macnotify_e notif, FAR const union ieee802154_mlme_notify_u *arg) { FAR struct mac802154dev_callback_s *cb = (FAR struct mac802154dev_callback_s *)maccb; FAR struct mac802154_chardevice_s *dev; DEBUGASSERT(cb != NULL && cb->mc_priv != NULL); dev = cb->mc_priv; switch (notif) { #warning Handle MLME notifications default: break; } } static void mac802154dev_mcps_notify(FAR const struct ieee802154_maccb_s *maccb, enum ieee802154_macnotify_e notif, FAR const union ieee802154_mcps_notify_u *arg) { FAR struct mac802154dev_callback_s *cb = (FAR struct mac802154dev_callback_s *)maccb; FAR struct mac802154_chardevice_s *dev; DEBUGASSERT(cb != NULL && cb->mc_priv != NULL); dev = cb->mc_priv; switch (notif) { case IEEE802154_NOTIFY_CONF_DATA: { mac802154dev_conf_data(dev, &arg->dataconf); } break; default: break; } } static void mac802154dev_conf_data(FAR struct mac802154_chardevice_s *dev, FAR const struct ieee802154_data_conf_s *conf) { FAR struct mac802154dev_dwait_s *curr; FAR struct mac802154dev_dwait_s *prev; /* Get exclusive access to the driver structure. We don't care about any * signals so if we see one, just go back to trying to get access again */ while (mac802154dev_takesem(&dev->md_exclsem) != 0); /* Search to see if there is a dwait pending for this transaction */ for (prev = NULL, curr = dev->md_dwait; curr && curr->mw_handle != conf->handle; prev = curr, curr = curr->mw_flink); /* If a dwait is found */ if (curr) { /* Unlink the structure from the list. The struct should be allocated on * the calling write's stack, so we don't need to worry about deallocating * here */ if (prev) { prev->mw_flink = curr->mw_flink; } else { dev->md_dwait = curr->mw_flink; } /* Copy the transmission status into the dwait struct */ curr->mw_status = conf->status; /* Wake the thread waiting for the data transmission */ sem_post(&curr->mw_sem); /* Release the driver */ mac802154dev_givesem(&dev->md_exclsem); } #ifndef CONFIG_DISABLE_SIGNALS /* Send a signal to the registered application */ #ifdef CONFIG_CAN_PASS_STRUCTS /* Copy the status as the signal data to be optionally used by app */ union sigval value; value.sival_int = (int)conf->status; (void)sigqueue(dev->md_mcps_pid, dev->md_mcps_notify.mn_signo, value); #else (void)sigqueue(dev->md_mcps_pid, dev->md_mcps_notify.mn_signo, value.sival_ptr); #endif #endif } /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: mac802154dev_register * * Description: * Register a character driver to access the IEEE 802.15.4 MAC layer from * user-space * * Input Parameters: * mac - Pointer to the mac layer struct to be registerd. * minor - The device minor number. The IEEE802.15.4 MAC character device * will be registered as /dev/ieeeN where N is the minor number * * Returned Values: * Zero (OK) is returned on success. Otherwise a negated errno value is * returned to indicate the nature of the failure. * ****************************************************************************/ int mac802154dev_register(MACHANDLE mac, int minor) { FAR struct mac802154_chardevice_s *dev; FAR struct ieee802154_maccb_s *maccb; char devname[DEVNAME_FMTLEN]; int ret; dev = kmm_zalloc(sizeof(struct mac802154_chardevice_s)); if (!dev) { wlerr("ERROR: Failed to allocate device structure\n"); return -ENOMEM; } /* Initialize the new mac driver instance */ dev->md_mac = mac; sem_init(&dev->md_exclsem, 0, 1); /* Allow the device to be opened once * before blocking */ /* Initialize the MAC callbacks */ dev->md_cb.mc_priv = dev; maccb = &dev->md_cb.mc_cb; maccb->mlme_notify = mac802154dev_mlme_notify; maccb->mcps_notify = mac802154dev_mcps_notify; /* Bind the callback structure */ ret = mac802154_bind(mac, maccb); if (ret < 0) { nerr("ERROR: Failed to bind the MAC callbacks: %d\n", ret); /* Free memory and return the error */ kmm_free(dev); return ret; } /* Create the character device name */ snprintf(devname, DEVNAME_FMTLEN, DEVNAME_FMT, minor); /* Register the mac character driver */ ret = register_driver(devname, &mac802154dev_fops, 0666, dev); if (ret < 0) { wlerr("ERROR: register_driver failed: %d\n", ret); goto errout_with_priv; } return OK; errout_with_priv: sem_destroy(&dev->md_exclsem); kmm_free(dev); return ret; }