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- // SPDX-License-Identifier: GPL-2.0
- /*
- * Copyright (C) 2015-2017 Pengutronix, Uwe Kleine-König <[email protected]>
- */
- #include <linux/kernel.h>
- #include <linux/device.h>
- #include <linux/module.h>
- #include <linux/slab.h>
- #include <linux/sysfs.h>
- #include "siox.h"
- /*
- * The lowest bit in the SIOX status word signals if the in-device watchdog is
- * ok. If the bit is set, the device is functional.
- *
- * On writing the watchdog timer is reset when this bit toggles.
- */
- #define SIOX_STATUS_WDG 0x01
- /*
- * Bits 1 to 3 of the status word read as the bitwise negation of what was
- * clocked in before. The value clocked in is changed in each cycle and so
- * allows to detect transmit/receive problems.
- */
- #define SIOX_STATUS_COUNTER 0x0e
- /*
- * Each Siox-Device has a 4 bit type number that is neither 0 nor 15. This is
- * available in the upper nibble of the read status.
- *
- * On write these bits are DC.
- */
- #define SIOX_STATUS_TYPE 0xf0
- #define CREATE_TRACE_POINTS
- #include <trace/events/siox.h>
- static bool siox_is_registered;
- static void siox_master_lock(struct siox_master *smaster)
- {
- mutex_lock(&smaster->lock);
- }
- static void siox_master_unlock(struct siox_master *smaster)
- {
- mutex_unlock(&smaster->lock);
- }
- static inline u8 siox_status_clean(u8 status_read, u8 status_written)
- {
- /*
- * bits 3:1 of status sample the respective bit in the status
- * byte written in the previous cycle but inverted. So if you wrote the
- * status word as 0xa before (counter = 0b101), it is expected to get
- * back the counter bits as 0b010.
- *
- * So given the last status written this function toggles the there
- * unset counter bits in the read value such that the counter bits in
- * the return value are all zero iff the bits were read as expected to
- * simplify error detection.
- */
- return status_read ^ (~status_written & 0xe);
- }
- static bool siox_device_counter_error(struct siox_device *sdevice,
- u8 status_clean)
- {
- return (status_clean & SIOX_STATUS_COUNTER) != 0;
- }
- static bool siox_device_type_error(struct siox_device *sdevice, u8 status_clean)
- {
- u8 statustype = (status_clean & SIOX_STATUS_TYPE) >> 4;
- /*
- * If the device knows which value the type bits should have, check
- * against this value otherwise just rule out the invalid values 0b0000
- * and 0b1111.
- */
- if (sdevice->statustype) {
- if (statustype != sdevice->statustype)
- return true;
- } else {
- switch (statustype) {
- case 0:
- case 0xf:
- return true;
- }
- }
- return false;
- }
- static bool siox_device_wdg_error(struct siox_device *sdevice, u8 status_clean)
- {
- return (status_clean & SIOX_STATUS_WDG) == 0;
- }
- /*
- * If there is a type or counter error the device is called "unsynced".
- */
- bool siox_device_synced(struct siox_device *sdevice)
- {
- if (siox_device_type_error(sdevice, sdevice->status_read_clean))
- return false;
- return !siox_device_counter_error(sdevice, sdevice->status_read_clean);
- }
- EXPORT_SYMBOL_GPL(siox_device_synced);
- /*
- * A device is called "connected" if it is synced and the watchdog is not
- * asserted.
- */
- bool siox_device_connected(struct siox_device *sdevice)
- {
- if (!siox_device_synced(sdevice))
- return false;
- return !siox_device_wdg_error(sdevice, sdevice->status_read_clean);
- }
- EXPORT_SYMBOL_GPL(siox_device_connected);
- static void siox_poll(struct siox_master *smaster)
- {
- struct siox_device *sdevice;
- size_t i = smaster->setbuf_len;
- unsigned int devno = 0;
- int unsync_error = 0;
- smaster->last_poll = jiffies;
- /*
- * The counter bits change in each second cycle, the watchdog bit
- * toggles each time.
- * The counter bits hold values from [0, 6]. 7 would be possible
- * theoretically but the protocol designer considered that a bad idea
- * for reasons unknown today. (Maybe that's because then the status read
- * back has only zeros in the counter bits then which might be confused
- * with a stuck-at-0 error. But for the same reason (with s/0/1/) 0
- * could be skipped.)
- */
- if (++smaster->status > 0x0d)
- smaster->status = 0;
- memset(smaster->buf, 0, smaster->setbuf_len);
- /* prepare data pushed out to devices in buf[0..setbuf_len) */
- list_for_each_entry(sdevice, &smaster->devices, node) {
- struct siox_driver *sdriver =
- to_siox_driver(sdevice->dev.driver);
- sdevice->status_written = smaster->status;
- i -= sdevice->inbytes;
- /*
- * If the device or a previous one is unsynced, don't pet the
- * watchdog. This is done to ensure that the device is kept in
- * reset when something is wrong.
- */
- if (!siox_device_synced(sdevice))
- unsync_error = 1;
- if (sdriver && !unsync_error)
- sdriver->set_data(sdevice, sdevice->status_written,
- &smaster->buf[i + 1]);
- else
- /*
- * Don't trigger watchdog if there is no driver or a
- * sync problem
- */
- sdevice->status_written &= ~SIOX_STATUS_WDG;
- smaster->buf[i] = sdevice->status_written;
- trace_siox_set_data(smaster, sdevice, devno, i);
- devno++;
- }
- smaster->pushpull(smaster, smaster->setbuf_len, smaster->buf,
- smaster->getbuf_len,
- smaster->buf + smaster->setbuf_len);
- unsync_error = 0;
- /* interpret data pulled in from devices in buf[setbuf_len..] */
- devno = 0;
- i = smaster->setbuf_len;
- list_for_each_entry(sdevice, &smaster->devices, node) {
- struct siox_driver *sdriver =
- to_siox_driver(sdevice->dev.driver);
- u8 status = smaster->buf[i + sdevice->outbytes - 1];
- u8 status_clean;
- u8 prev_status_clean = sdevice->status_read_clean;
- bool synced = true;
- bool connected = true;
- if (!siox_device_synced(sdevice))
- unsync_error = 1;
- /*
- * If the watchdog bit wasn't toggled in this cycle, report the
- * watchdog as active to give a consistent view for drivers and
- * sysfs consumers.
- */
- if (!sdriver || unsync_error)
- status &= ~SIOX_STATUS_WDG;
- status_clean =
- siox_status_clean(status,
- sdevice->status_written_lastcycle);
- /* Check counter and type bits */
- if (siox_device_counter_error(sdevice, status_clean) ||
- siox_device_type_error(sdevice, status_clean)) {
- bool prev_error;
- synced = false;
- /* only report a new error if the last cycle was ok */
- prev_error =
- siox_device_counter_error(sdevice,
- prev_status_clean) ||
- siox_device_type_error(sdevice,
- prev_status_clean);
- if (!prev_error) {
- sdevice->status_errors++;
- sysfs_notify_dirent(sdevice->status_errors_kn);
- }
- }
- /* If the device is unsynced report the watchdog as active */
- if (!synced) {
- status &= ~SIOX_STATUS_WDG;
- status_clean &= ~SIOX_STATUS_WDG;
- }
- if (siox_device_wdg_error(sdevice, status_clean))
- connected = false;
- /* The watchdog state changed just now */
- if ((status_clean ^ prev_status_clean) & SIOX_STATUS_WDG) {
- sysfs_notify_dirent(sdevice->watchdog_kn);
- if (siox_device_wdg_error(sdevice, status_clean)) {
- struct kernfs_node *wd_errs =
- sdevice->watchdog_errors_kn;
- sdevice->watchdog_errors++;
- sysfs_notify_dirent(wd_errs);
- }
- }
- if (connected != sdevice->connected)
- sysfs_notify_dirent(sdevice->connected_kn);
- sdevice->status_read_clean = status_clean;
- sdevice->status_written_lastcycle = sdevice->status_written;
- sdevice->connected = connected;
- trace_siox_get_data(smaster, sdevice, devno, status_clean, i);
- /* only give data read to driver if the device is connected */
- if (sdriver && connected)
- sdriver->get_data(sdevice, &smaster->buf[i]);
- devno++;
- i += sdevice->outbytes;
- }
- }
- static int siox_poll_thread(void *data)
- {
- struct siox_master *smaster = data;
- signed long timeout = 0;
- get_device(&smaster->dev);
- for (;;) {
- if (kthread_should_stop()) {
- put_device(&smaster->dev);
- return 0;
- }
- siox_master_lock(smaster);
- if (smaster->active) {
- unsigned long next_poll =
- smaster->last_poll + smaster->poll_interval;
- if (time_is_before_eq_jiffies(next_poll))
- siox_poll(smaster);
- timeout = smaster->poll_interval -
- (jiffies - smaster->last_poll);
- } else {
- timeout = MAX_SCHEDULE_TIMEOUT;
- }
- /*
- * Set the task to idle while holding the lock. This makes sure
- * that we don't sleep too long when the bus is reenabled before
- * schedule_timeout is reached.
- */
- if (timeout > 0)
- set_current_state(TASK_IDLE);
- siox_master_unlock(smaster);
- if (timeout > 0)
- schedule_timeout(timeout);
- /*
- * I'm not clear if/why it is important to set the state to
- * RUNNING again, but it fixes a "do not call blocking ops when
- * !TASK_RUNNING;"-warning.
- */
- set_current_state(TASK_RUNNING);
- }
- }
- static int __siox_start(struct siox_master *smaster)
- {
- if (!(smaster->setbuf_len + smaster->getbuf_len))
- return -ENODEV;
- if (!smaster->buf)
- return -ENOMEM;
- if (smaster->active)
- return 0;
- smaster->active = 1;
- wake_up_process(smaster->poll_thread);
- return 1;
- }
- static int siox_start(struct siox_master *smaster)
- {
- int ret;
- siox_master_lock(smaster);
- ret = __siox_start(smaster);
- siox_master_unlock(smaster);
- return ret;
- }
- static int __siox_stop(struct siox_master *smaster)
- {
- if (smaster->active) {
- struct siox_device *sdevice;
- smaster->active = 0;
- list_for_each_entry(sdevice, &smaster->devices, node) {
- if (sdevice->connected)
- sysfs_notify_dirent(sdevice->connected_kn);
- sdevice->connected = false;
- }
- return 1;
- }
- return 0;
- }
- static int siox_stop(struct siox_master *smaster)
- {
- int ret;
- siox_master_lock(smaster);
- ret = __siox_stop(smaster);
- siox_master_unlock(smaster);
- return ret;
- }
- static ssize_t type_show(struct device *dev,
- struct device_attribute *attr, char *buf)
- {
- struct siox_device *sdev = to_siox_device(dev);
- return sprintf(buf, "%s\n", sdev->type);
- }
- static DEVICE_ATTR_RO(type);
- static ssize_t inbytes_show(struct device *dev,
- struct device_attribute *attr, char *buf)
- {
- struct siox_device *sdev = to_siox_device(dev);
- return sprintf(buf, "%zu\n", sdev->inbytes);
- }
- static DEVICE_ATTR_RO(inbytes);
- static ssize_t outbytes_show(struct device *dev,
- struct device_attribute *attr, char *buf)
- {
- struct siox_device *sdev = to_siox_device(dev);
- return sprintf(buf, "%zu\n", sdev->outbytes);
- }
- static DEVICE_ATTR_RO(outbytes);
- static ssize_t status_errors_show(struct device *dev,
- struct device_attribute *attr, char *buf)
- {
- struct siox_device *sdev = to_siox_device(dev);
- unsigned int status_errors;
- siox_master_lock(sdev->smaster);
- status_errors = sdev->status_errors;
- siox_master_unlock(sdev->smaster);
- return sprintf(buf, "%u\n", status_errors);
- }
- static DEVICE_ATTR_RO(status_errors);
- static ssize_t connected_show(struct device *dev,
- struct device_attribute *attr, char *buf)
- {
- struct siox_device *sdev = to_siox_device(dev);
- bool connected;
- siox_master_lock(sdev->smaster);
- connected = sdev->connected;
- siox_master_unlock(sdev->smaster);
- return sprintf(buf, "%u\n", connected);
- }
- static DEVICE_ATTR_RO(connected);
- static ssize_t watchdog_show(struct device *dev,
- struct device_attribute *attr, char *buf)
- {
- struct siox_device *sdev = to_siox_device(dev);
- u8 status;
- siox_master_lock(sdev->smaster);
- status = sdev->status_read_clean;
- siox_master_unlock(sdev->smaster);
- return sprintf(buf, "%d\n", status & SIOX_STATUS_WDG);
- }
- static DEVICE_ATTR_RO(watchdog);
- static ssize_t watchdog_errors_show(struct device *dev,
- struct device_attribute *attr, char *buf)
- {
- struct siox_device *sdev = to_siox_device(dev);
- unsigned int watchdog_errors;
- siox_master_lock(sdev->smaster);
- watchdog_errors = sdev->watchdog_errors;
- siox_master_unlock(sdev->smaster);
- return sprintf(buf, "%u\n", watchdog_errors);
- }
- static DEVICE_ATTR_RO(watchdog_errors);
- static struct attribute *siox_device_attrs[] = {
- &dev_attr_type.attr,
- &dev_attr_inbytes.attr,
- &dev_attr_outbytes.attr,
- &dev_attr_status_errors.attr,
- &dev_attr_connected.attr,
- &dev_attr_watchdog.attr,
- &dev_attr_watchdog_errors.attr,
- NULL
- };
- ATTRIBUTE_GROUPS(siox_device);
- static void siox_device_release(struct device *dev)
- {
- struct siox_device *sdevice = to_siox_device(dev);
- kfree(sdevice);
- }
- static struct device_type siox_device_type = {
- .groups = siox_device_groups,
- .release = siox_device_release,
- };
- static int siox_match(struct device *dev, struct device_driver *drv)
- {
- if (dev->type != &siox_device_type)
- return 0;
- /* up to now there is only a single driver so keeping this simple */
- return 1;
- }
- static int siox_probe(struct device *dev)
- {
- struct siox_driver *sdriver = to_siox_driver(dev->driver);
- struct siox_device *sdevice = to_siox_device(dev);
- return sdriver->probe(sdevice);
- }
- static void siox_remove(struct device *dev)
- {
- struct siox_driver *sdriver =
- container_of(dev->driver, struct siox_driver, driver);
- struct siox_device *sdevice = to_siox_device(dev);
- if (sdriver->remove)
- sdriver->remove(sdevice);
- }
- static void siox_shutdown(struct device *dev)
- {
- struct siox_device *sdevice = to_siox_device(dev);
- struct siox_driver *sdriver;
- if (!dev->driver)
- return;
- sdriver = container_of(dev->driver, struct siox_driver, driver);
- if (sdriver->shutdown)
- sdriver->shutdown(sdevice);
- }
- static struct bus_type siox_bus_type = {
- .name = "siox",
- .match = siox_match,
- .probe = siox_probe,
- .remove = siox_remove,
- .shutdown = siox_shutdown,
- };
- static ssize_t active_show(struct device *dev,
- struct device_attribute *attr, char *buf)
- {
- struct siox_master *smaster = to_siox_master(dev);
- return sprintf(buf, "%d\n", smaster->active);
- }
- static ssize_t active_store(struct device *dev,
- struct device_attribute *attr,
- const char *buf, size_t count)
- {
- struct siox_master *smaster = to_siox_master(dev);
- int ret;
- int active;
- ret = kstrtoint(buf, 0, &active);
- if (ret < 0)
- return ret;
- if (active)
- ret = siox_start(smaster);
- else
- ret = siox_stop(smaster);
- if (ret < 0)
- return ret;
- return count;
- }
- static DEVICE_ATTR_RW(active);
- static struct siox_device *siox_device_add(struct siox_master *smaster,
- const char *type, size_t inbytes,
- size_t outbytes, u8 statustype);
- static ssize_t device_add_store(struct device *dev,
- struct device_attribute *attr,
- const char *buf, size_t count)
- {
- struct siox_master *smaster = to_siox_master(dev);
- int ret;
- char type[20] = "";
- size_t inbytes = 0, outbytes = 0;
- u8 statustype = 0;
- ret = sscanf(buf, "%19s %zu %zu %hhu", type, &inbytes,
- &outbytes, &statustype);
- if (ret != 3 && ret != 4)
- return -EINVAL;
- if (strcmp(type, "siox-12x8") || inbytes != 2 || outbytes != 4)
- return -EINVAL;
- siox_device_add(smaster, "siox-12x8", inbytes, outbytes, statustype);
- return count;
- }
- static DEVICE_ATTR_WO(device_add);
- static void siox_device_remove(struct siox_master *smaster);
- static ssize_t device_remove_store(struct device *dev,
- struct device_attribute *attr,
- const char *buf, size_t count)
- {
- struct siox_master *smaster = to_siox_master(dev);
- /* XXX? require to write <type> <inbytes> <outbytes> */
- siox_device_remove(smaster);
- return count;
- }
- static DEVICE_ATTR_WO(device_remove);
- static ssize_t poll_interval_ns_show(struct device *dev,
- struct device_attribute *attr, char *buf)
- {
- struct siox_master *smaster = to_siox_master(dev);
- return sprintf(buf, "%lld\n", jiffies_to_nsecs(smaster->poll_interval));
- }
- static ssize_t poll_interval_ns_store(struct device *dev,
- struct device_attribute *attr,
- const char *buf, size_t count)
- {
- struct siox_master *smaster = to_siox_master(dev);
- int ret;
- u64 val;
- ret = kstrtou64(buf, 0, &val);
- if (ret < 0)
- return ret;
- siox_master_lock(smaster);
- smaster->poll_interval = nsecs_to_jiffies(val);
- siox_master_unlock(smaster);
- return count;
- }
- static DEVICE_ATTR_RW(poll_interval_ns);
- static struct attribute *siox_master_attrs[] = {
- &dev_attr_active.attr,
- &dev_attr_device_add.attr,
- &dev_attr_device_remove.attr,
- &dev_attr_poll_interval_ns.attr,
- NULL
- };
- ATTRIBUTE_GROUPS(siox_master);
- static void siox_master_release(struct device *dev)
- {
- struct siox_master *smaster = to_siox_master(dev);
- kfree(smaster);
- }
- static struct device_type siox_master_type = {
- .groups = siox_master_groups,
- .release = siox_master_release,
- };
- struct siox_master *siox_master_alloc(struct device *dev,
- size_t size)
- {
- struct siox_master *smaster;
- if (!dev)
- return NULL;
- smaster = kzalloc(sizeof(*smaster) + size, GFP_KERNEL);
- if (!smaster)
- return NULL;
- device_initialize(&smaster->dev);
- smaster->busno = -1;
- smaster->dev.bus = &siox_bus_type;
- smaster->dev.type = &siox_master_type;
- smaster->dev.parent = dev;
- smaster->poll_interval = DIV_ROUND_UP(HZ, 40);
- dev_set_drvdata(&smaster->dev, &smaster[1]);
- return smaster;
- }
- EXPORT_SYMBOL_GPL(siox_master_alloc);
- int siox_master_register(struct siox_master *smaster)
- {
- int ret;
- if (!siox_is_registered)
- return -EPROBE_DEFER;
- if (!smaster->pushpull)
- return -EINVAL;
- dev_set_name(&smaster->dev, "siox-%d", smaster->busno);
- mutex_init(&smaster->lock);
- INIT_LIST_HEAD(&smaster->devices);
- smaster->last_poll = jiffies;
- smaster->poll_thread = kthread_run(siox_poll_thread, smaster,
- "siox-%d", smaster->busno);
- if (IS_ERR(smaster->poll_thread)) {
- smaster->active = 0;
- return PTR_ERR(smaster->poll_thread);
- }
- ret = device_add(&smaster->dev);
- if (ret)
- kthread_stop(smaster->poll_thread);
- return ret;
- }
- EXPORT_SYMBOL_GPL(siox_master_register);
- void siox_master_unregister(struct siox_master *smaster)
- {
- /* remove device */
- device_del(&smaster->dev);
- siox_master_lock(smaster);
- __siox_stop(smaster);
- while (smaster->num_devices) {
- struct siox_device *sdevice;
- sdevice = container_of(smaster->devices.prev,
- struct siox_device, node);
- list_del(&sdevice->node);
- smaster->num_devices--;
- siox_master_unlock(smaster);
- device_unregister(&sdevice->dev);
- siox_master_lock(smaster);
- }
- siox_master_unlock(smaster);
- put_device(&smaster->dev);
- }
- EXPORT_SYMBOL_GPL(siox_master_unregister);
- static struct siox_device *siox_device_add(struct siox_master *smaster,
- const char *type, size_t inbytes,
- size_t outbytes, u8 statustype)
- {
- struct siox_device *sdevice;
- int ret;
- size_t buf_len;
- sdevice = kzalloc(sizeof(*sdevice), GFP_KERNEL);
- if (!sdevice)
- return ERR_PTR(-ENOMEM);
- sdevice->type = type;
- sdevice->inbytes = inbytes;
- sdevice->outbytes = outbytes;
- sdevice->statustype = statustype;
- sdevice->smaster = smaster;
- sdevice->dev.parent = &smaster->dev;
- sdevice->dev.bus = &siox_bus_type;
- sdevice->dev.type = &siox_device_type;
- siox_master_lock(smaster);
- dev_set_name(&sdevice->dev, "siox-%d-%d",
- smaster->busno, smaster->num_devices);
- buf_len = smaster->setbuf_len + inbytes +
- smaster->getbuf_len + outbytes;
- if (smaster->buf_len < buf_len) {
- u8 *buf = krealloc(smaster->buf, buf_len, GFP_KERNEL);
- if (!buf) {
- dev_err(&smaster->dev,
- "failed to realloc buffer to %zu\n", buf_len);
- ret = -ENOMEM;
- goto err_buf_alloc;
- }
- smaster->buf_len = buf_len;
- smaster->buf = buf;
- }
- ret = device_register(&sdevice->dev);
- if (ret) {
- dev_err(&smaster->dev, "failed to register device: %d\n", ret);
- goto err_device_register;
- }
- smaster->num_devices++;
- list_add_tail(&sdevice->node, &smaster->devices);
- smaster->setbuf_len += sdevice->inbytes;
- smaster->getbuf_len += sdevice->outbytes;
- sdevice->status_errors_kn = sysfs_get_dirent(sdevice->dev.kobj.sd,
- "status_errors");
- sdevice->watchdog_kn = sysfs_get_dirent(sdevice->dev.kobj.sd,
- "watchdog");
- sdevice->watchdog_errors_kn = sysfs_get_dirent(sdevice->dev.kobj.sd,
- "watchdog_errors");
- sdevice->connected_kn = sysfs_get_dirent(sdevice->dev.kobj.sd,
- "connected");
- siox_master_unlock(smaster);
- return sdevice;
- err_device_register:
- /* don't care to make the buffer smaller again */
- put_device(&sdevice->dev);
- sdevice = NULL;
- err_buf_alloc:
- siox_master_unlock(smaster);
- kfree(sdevice);
- return ERR_PTR(ret);
- }
- static void siox_device_remove(struct siox_master *smaster)
- {
- struct siox_device *sdevice;
- siox_master_lock(smaster);
- if (!smaster->num_devices) {
- siox_master_unlock(smaster);
- return;
- }
- sdevice = container_of(smaster->devices.prev, struct siox_device, node);
- list_del(&sdevice->node);
- smaster->num_devices--;
- smaster->setbuf_len -= sdevice->inbytes;
- smaster->getbuf_len -= sdevice->outbytes;
- if (!smaster->num_devices)
- __siox_stop(smaster);
- siox_master_unlock(smaster);
- /*
- * This must be done without holding the master lock because we're
- * called from device_remove_store which also holds a sysfs mutex.
- * device_unregister tries to aquire the same lock.
- */
- device_unregister(&sdevice->dev);
- }
- int __siox_driver_register(struct siox_driver *sdriver, struct module *owner)
- {
- int ret;
- if (unlikely(!siox_is_registered))
- return -EPROBE_DEFER;
- if (!sdriver->probe ||
- (!sdriver->set_data && !sdriver->get_data)) {
- pr_err("Driver %s doesn't provide needed callbacks\n",
- sdriver->driver.name);
- return -EINVAL;
- }
- sdriver->driver.owner = owner;
- sdriver->driver.bus = &siox_bus_type;
- ret = driver_register(&sdriver->driver);
- if (ret)
- pr_err("Failed to register siox driver %s (%d)\n",
- sdriver->driver.name, ret);
- return ret;
- }
- EXPORT_SYMBOL_GPL(__siox_driver_register);
- static int __init siox_init(void)
- {
- int ret;
- ret = bus_register(&siox_bus_type);
- if (ret) {
- pr_err("Registration of SIOX bus type failed: %d\n", ret);
- return ret;
- }
- siox_is_registered = true;
- return 0;
- }
- subsys_initcall(siox_init);
- static void __exit siox_exit(void)
- {
- bus_unregister(&siox_bus_type);
- }
- module_exit(siox_exit);
- MODULE_AUTHOR("Uwe Kleine-Koenig <[email protected]>");
- MODULE_DESCRIPTION("Eckelmann SIOX driver core");
- MODULE_LICENSE("GPL v2");
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