| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * core.c - Implementation of core module of MOST Linux driver stack |
| * |
| * Copyright (C) 2013-2015 Microchip Technology Germany II GmbH & Co. KG |
| */ |
| |
| #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| #include <linux/module.h> |
| #include <linux/fs.h> |
| #include <linux/slab.h> |
| #include <linux/init.h> |
| #include <linux/device.h> |
| #include <linux/list.h> |
| #include <linux/poll.h> |
| #include <linux/wait.h> |
| #include <linux/kobject.h> |
| #include <linux/mutex.h> |
| #include <linux/completion.h> |
| #include <linux/sysfs.h> |
| #include <linux/kthread.h> |
| #include <linux/dma-mapping.h> |
| #include <linux/idr.h> |
| #include <most/core.h> |
| |
| #define MAX_CHANNELS 64 |
| #define STRING_SIZE 80 |
| |
| static struct ida mdev_id; |
| static int dummy_num_buffers; |
| |
| static struct mostcore { |
| struct device dev; |
| struct device_driver drv; |
| struct bus_type bus; |
| struct list_head comp_list; |
| } mc; |
| |
| #define to_driver(d) container_of(d, struct mostcore, drv) |
| |
| struct pipe { |
| struct core_component *comp; |
| int refs; |
| int num_buffers; |
| }; |
| |
| struct most_channel { |
| struct device dev; |
| struct completion cleanup; |
| atomic_t mbo_ref; |
| atomic_t mbo_nq_level; |
| u16 channel_id; |
| char name[STRING_SIZE]; |
| bool is_poisoned; |
| struct mutex start_mutex; |
| struct mutex nq_mutex; /* nq thread synchronization */ |
| int is_starving; |
| struct most_interface *iface; |
| struct most_channel_config cfg; |
| bool keep_mbo; |
| bool enqueue_halt; |
| struct list_head fifo; |
| spinlock_t fifo_lock; |
| struct list_head halt_fifo; |
| struct list_head list; |
| struct pipe pipe0; |
| struct pipe pipe1; |
| struct list_head trash_fifo; |
| struct task_struct *hdm_enqueue_task; |
| wait_queue_head_t hdm_fifo_wq; |
| |
| }; |
| |
| #define to_channel(d) container_of(d, struct most_channel, dev) |
| |
| struct interface_private { |
| int dev_id; |
| char name[STRING_SIZE]; |
| struct most_channel *channel[MAX_CHANNELS]; |
| struct list_head channel_list; |
| }; |
| |
| static const struct { |
| int most_ch_data_type; |
| const char *name; |
| } ch_data_type[] = { |
| { MOST_CH_CONTROL, "control\n" }, |
| { MOST_CH_ASYNC, "async\n" }, |
| { MOST_CH_SYNC, "sync\n" }, |
| { MOST_CH_ISOC, "isoc\n"}, |
| { MOST_CH_ISOC, "isoc_avp\n"}, |
| }; |
| |
| /** |
| * list_pop_mbo - retrieves the first MBO of the list and removes it |
| * @ptr: the list head to grab the MBO from. |
| */ |
| #define list_pop_mbo(ptr) \ |
| ({ \ |
| struct mbo *_mbo = list_first_entry(ptr, struct mbo, list); \ |
| list_del(&_mbo->list); \ |
| _mbo; \ |
| }) |
| |
| /** |
| * most_free_mbo_coherent - free an MBO and its coherent buffer |
| * @mbo: most buffer |
| */ |
| static void most_free_mbo_coherent(struct mbo *mbo) |
| { |
| struct most_channel *c = mbo->context; |
| u16 const coherent_buf_size = c->cfg.buffer_size + c->cfg.extra_len; |
| |
| if (c->iface->dma_free) |
| c->iface->dma_free(mbo, coherent_buf_size); |
| else |
| kfree(mbo->virt_address); |
| kfree(mbo); |
| if (atomic_sub_and_test(1, &c->mbo_ref)) |
| complete(&c->cleanup); |
| } |
| |
| /** |
| * flush_channel_fifos - clear the channel fifos |
| * @c: pointer to channel object |
| */ |
| static void flush_channel_fifos(struct most_channel *c) |
| { |
| unsigned long flags, hf_flags; |
| struct mbo *mbo, *tmp; |
| |
| if (list_empty(&c->fifo) && list_empty(&c->halt_fifo)) |
| return; |
| |
| spin_lock_irqsave(&c->fifo_lock, flags); |
| list_for_each_entry_safe(mbo, tmp, &c->fifo, list) { |
| list_del(&mbo->list); |
| spin_unlock_irqrestore(&c->fifo_lock, flags); |
| most_free_mbo_coherent(mbo); |
| spin_lock_irqsave(&c->fifo_lock, flags); |
| } |
| spin_unlock_irqrestore(&c->fifo_lock, flags); |
| |
| spin_lock_irqsave(&c->fifo_lock, hf_flags); |
| list_for_each_entry_safe(mbo, tmp, &c->halt_fifo, list) { |
| list_del(&mbo->list); |
| spin_unlock_irqrestore(&c->fifo_lock, hf_flags); |
| most_free_mbo_coherent(mbo); |
| spin_lock_irqsave(&c->fifo_lock, hf_flags); |
| } |
| spin_unlock_irqrestore(&c->fifo_lock, hf_flags); |
| |
| if (unlikely((!list_empty(&c->fifo) || !list_empty(&c->halt_fifo)))) |
| pr_info("WARN: fifo | trash fifo not empty\n"); |
| } |
| |
| /** |
| * flush_trash_fifo - clear the trash fifo |
| * @c: pointer to channel object |
| */ |
| static int flush_trash_fifo(struct most_channel *c) |
| { |
| struct mbo *mbo, *tmp; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&c->fifo_lock, flags); |
| list_for_each_entry_safe(mbo, tmp, &c->trash_fifo, list) { |
| list_del(&mbo->list); |
| spin_unlock_irqrestore(&c->fifo_lock, flags); |
| most_free_mbo_coherent(mbo); |
| spin_lock_irqsave(&c->fifo_lock, flags); |
| } |
| spin_unlock_irqrestore(&c->fifo_lock, flags); |
| return 0; |
| } |
| |
| static ssize_t available_directions_show(struct device *dev, |
| struct device_attribute *attr, |
| char *buf) |
| { |
| struct most_channel *c = to_channel(dev); |
| unsigned int i = c->channel_id; |
| |
| strcpy(buf, ""); |
| if (c->iface->channel_vector[i].direction & MOST_CH_RX) |
| strcat(buf, "rx "); |
| if (c->iface->channel_vector[i].direction & MOST_CH_TX) |
| strcat(buf, "tx "); |
| strcat(buf, "\n"); |
| return strlen(buf); |
| } |
| |
| static ssize_t available_datatypes_show(struct device *dev, |
| struct device_attribute *attr, |
| char *buf) |
| { |
| struct most_channel *c = to_channel(dev); |
| unsigned int i = c->channel_id; |
| |
| strcpy(buf, ""); |
| if (c->iface->channel_vector[i].data_type & MOST_CH_CONTROL) |
| strcat(buf, "control "); |
| if (c->iface->channel_vector[i].data_type & MOST_CH_ASYNC) |
| strcat(buf, "async "); |
| if (c->iface->channel_vector[i].data_type & MOST_CH_SYNC) |
| strcat(buf, "sync "); |
| if (c->iface->channel_vector[i].data_type & MOST_CH_ISOC) |
| strcat(buf, "isoc "); |
| strcat(buf, "\n"); |
| return strlen(buf); |
| } |
| |
| static ssize_t number_of_packet_buffers_show(struct device *dev, |
| struct device_attribute *attr, |
| char *buf) |
| { |
| struct most_channel *c = to_channel(dev); |
| unsigned int i = c->channel_id; |
| |
| return snprintf(buf, PAGE_SIZE, "%d\n", |
| c->iface->channel_vector[i].num_buffers_packet); |
| } |
| |
| static ssize_t number_of_stream_buffers_show(struct device *dev, |
| struct device_attribute *attr, |
| char *buf) |
| { |
| struct most_channel *c = to_channel(dev); |
| unsigned int i = c->channel_id; |
| |
| return snprintf(buf, PAGE_SIZE, "%d\n", |
| c->iface->channel_vector[i].num_buffers_streaming); |
| } |
| |
| static ssize_t size_of_packet_buffer_show(struct device *dev, |
| struct device_attribute *attr, |
| char *buf) |
| { |
| struct most_channel *c = to_channel(dev); |
| unsigned int i = c->channel_id; |
| |
| return snprintf(buf, PAGE_SIZE, "%d\n", |
| c->iface->channel_vector[i].buffer_size_packet); |
| } |
| |
| static ssize_t size_of_stream_buffer_show(struct device *dev, |
| struct device_attribute *attr, |
| char *buf) |
| { |
| struct most_channel *c = to_channel(dev); |
| unsigned int i = c->channel_id; |
| |
| return snprintf(buf, PAGE_SIZE, "%d\n", |
| c->iface->channel_vector[i].buffer_size_streaming); |
| } |
| |
| static ssize_t channel_starving_show(struct device *dev, |
| struct device_attribute *attr, |
| char *buf) |
| { |
| struct most_channel *c = to_channel(dev); |
| |
| return snprintf(buf, PAGE_SIZE, "%d\n", c->is_starving); |
| } |
| |
| static ssize_t set_number_of_buffers_show(struct device *dev, |
| struct device_attribute *attr, |
| char *buf) |
| { |
| struct most_channel *c = to_channel(dev); |
| |
| return snprintf(buf, PAGE_SIZE, "%d\n", c->cfg.num_buffers); |
| } |
| |
| static ssize_t set_number_of_buffers_store(struct device *dev, |
| struct device_attribute *attr, |
| const char *buf, |
| size_t count) |
| { |
| struct most_channel *c = to_channel(dev); |
| int ret = kstrtou16(buf, 0, &c->cfg.num_buffers); |
| |
| if (ret) |
| return ret; |
| return count; |
| } |
| |
| static ssize_t set_buffer_size_show(struct device *dev, |
| struct device_attribute *attr, |
| char *buf) |
| { |
| struct most_channel *c = to_channel(dev); |
| |
| return snprintf(buf, PAGE_SIZE, "%d\n", c->cfg.buffer_size); |
| } |
| |
| static ssize_t set_buffer_size_store(struct device *dev, |
| struct device_attribute *attr, |
| const char *buf, |
| size_t count) |
| { |
| struct most_channel *c = to_channel(dev); |
| int ret = kstrtou16(buf, 0, &c->cfg.buffer_size); |
| |
| if (ret) |
| return ret; |
| return count; |
| } |
| |
| static ssize_t set_direction_show(struct device *dev, |
| struct device_attribute *attr, |
| char *buf) |
| { |
| struct most_channel *c = to_channel(dev); |
| |
| if (c->cfg.direction & MOST_CH_TX) |
| return snprintf(buf, PAGE_SIZE, "tx\n"); |
| else if (c->cfg.direction & MOST_CH_RX) |
| return snprintf(buf, PAGE_SIZE, "rx\n"); |
| return snprintf(buf, PAGE_SIZE, "unconfigured\n"); |
| } |
| |
| static ssize_t set_direction_store(struct device *dev, |
| struct device_attribute *attr, |
| const char *buf, |
| size_t count) |
| { |
| struct most_channel *c = to_channel(dev); |
| |
| if (!strcmp(buf, "dir_rx\n")) { |
| c->cfg.direction = MOST_CH_RX; |
| } else if (!strcmp(buf, "rx\n")) { |
| c->cfg.direction = MOST_CH_RX; |
| } else if (!strcmp(buf, "dir_tx\n")) { |
| c->cfg.direction = MOST_CH_TX; |
| } else if (!strcmp(buf, "tx\n")) { |
| c->cfg.direction = MOST_CH_TX; |
| } else { |
| pr_info("WARN: invalid attribute settings\n"); |
| return -EINVAL; |
| } |
| return count; |
| } |
| |
| static ssize_t set_datatype_show(struct device *dev, |
| struct device_attribute *attr, |
| char *buf) |
| { |
| int i; |
| struct most_channel *c = to_channel(dev); |
| |
| for (i = 0; i < ARRAY_SIZE(ch_data_type); i++) { |
| if (c->cfg.data_type & ch_data_type[i].most_ch_data_type) |
| return snprintf(buf, PAGE_SIZE, "%s", ch_data_type[i].name); |
| } |
| return snprintf(buf, PAGE_SIZE, "unconfigured\n"); |
| } |
| |
| static ssize_t set_datatype_store(struct device *dev, |
| struct device_attribute *attr, |
| const char *buf, |
| size_t count) |
| { |
| int i; |
| struct most_channel *c = to_channel(dev); |
| |
| for (i = 0; i < ARRAY_SIZE(ch_data_type); i++) { |
| if (!strcmp(buf, ch_data_type[i].name)) { |
| c->cfg.data_type = ch_data_type[i].most_ch_data_type; |
| break; |
| } |
| } |
| |
| if (i == ARRAY_SIZE(ch_data_type)) { |
| pr_info("WARN: invalid attribute settings\n"); |
| return -EINVAL; |
| } |
| return count; |
| } |
| |
| static ssize_t set_subbuffer_size_show(struct device *dev, |
| struct device_attribute *attr, |
| char *buf) |
| { |
| struct most_channel *c = to_channel(dev); |
| |
| return snprintf(buf, PAGE_SIZE, "%d\n", c->cfg.subbuffer_size); |
| } |
| |
| static ssize_t set_subbuffer_size_store(struct device *dev, |
| struct device_attribute *attr, |
| const char *buf, |
| size_t count) |
| { |
| struct most_channel *c = to_channel(dev); |
| int ret = kstrtou16(buf, 0, &c->cfg.subbuffer_size); |
| |
| if (ret) |
| return ret; |
| return count; |
| } |
| |
| static ssize_t set_packets_per_xact_show(struct device *dev, |
| struct device_attribute *attr, |
| char *buf) |
| { |
| struct most_channel *c = to_channel(dev); |
| |
| return snprintf(buf, PAGE_SIZE, "%d\n", c->cfg.packets_per_xact); |
| } |
| |
| static ssize_t set_packets_per_xact_store(struct device *dev, |
| struct device_attribute *attr, |
| const char *buf, |
| size_t count) |
| { |
| struct most_channel *c = to_channel(dev); |
| int ret = kstrtou16(buf, 0, &c->cfg.packets_per_xact); |
| |
| if (ret) |
| return ret; |
| return count; |
| } |
| |
| static ssize_t set_dbr_size_show(struct device *dev, |
| struct device_attribute *attr, char *buf) |
| { |
| struct most_channel *c = to_channel(dev); |
| |
| return snprintf(buf, PAGE_SIZE, "%d\n", c->cfg.dbr_size); |
| } |
| |
| static ssize_t set_dbr_size_store(struct device *dev, |
| struct device_attribute *attr, |
| const char *buf, size_t count) |
| { |
| struct most_channel *c = to_channel(dev); |
| int ret = kstrtou16(buf, 0, &c->cfg.dbr_size); |
| |
| if (ret) |
| return ret; |
| return count; |
| } |
| |
| #define to_dev_attr(a) container_of(a, struct device_attribute, attr) |
| static umode_t channel_attr_is_visible(struct kobject *kobj, |
| struct attribute *attr, int index) |
| { |
| struct device_attribute *dev_attr = to_dev_attr(attr); |
| struct device *dev = kobj_to_dev(kobj); |
| struct most_channel *c = to_channel(dev); |
| |
| if (!strcmp(dev_attr->attr.name, "set_dbr_size") && |
| (c->iface->interface != ITYPE_MEDIALB_DIM2)) |
| return 0; |
| if (!strcmp(dev_attr->attr.name, "set_packets_per_xact") && |
| (c->iface->interface != ITYPE_USB)) |
| return 0; |
| |
| return attr->mode; |
| } |
| |
| #define DEV_ATTR(_name) (&dev_attr_##_name.attr) |
| |
| static DEVICE_ATTR_RO(available_directions); |
| static DEVICE_ATTR_RO(available_datatypes); |
| static DEVICE_ATTR_RO(number_of_packet_buffers); |
| static DEVICE_ATTR_RO(number_of_stream_buffers); |
| static DEVICE_ATTR_RO(size_of_stream_buffer); |
| static DEVICE_ATTR_RO(size_of_packet_buffer); |
| static DEVICE_ATTR_RO(channel_starving); |
| static DEVICE_ATTR_RW(set_buffer_size); |
| static DEVICE_ATTR_RW(set_number_of_buffers); |
| static DEVICE_ATTR_RW(set_direction); |
| static DEVICE_ATTR_RW(set_datatype); |
| static DEVICE_ATTR_RW(set_subbuffer_size); |
| static DEVICE_ATTR_RW(set_packets_per_xact); |
| static DEVICE_ATTR_RW(set_dbr_size); |
| |
| static struct attribute *channel_attrs[] = { |
| DEV_ATTR(available_directions), |
| DEV_ATTR(available_datatypes), |
| DEV_ATTR(number_of_packet_buffers), |
| DEV_ATTR(number_of_stream_buffers), |
| DEV_ATTR(size_of_stream_buffer), |
| DEV_ATTR(size_of_packet_buffer), |
| DEV_ATTR(channel_starving), |
| DEV_ATTR(set_buffer_size), |
| DEV_ATTR(set_number_of_buffers), |
| DEV_ATTR(set_direction), |
| DEV_ATTR(set_datatype), |
| DEV_ATTR(set_subbuffer_size), |
| DEV_ATTR(set_packets_per_xact), |
| DEV_ATTR(set_dbr_size), |
| NULL, |
| }; |
| |
| static struct attribute_group channel_attr_group = { |
| .attrs = channel_attrs, |
| .is_visible = channel_attr_is_visible, |
| }; |
| |
| static const struct attribute_group *channel_attr_groups[] = { |
| &channel_attr_group, |
| NULL, |
| }; |
| |
| static ssize_t description_show(struct device *dev, |
| struct device_attribute *attr, |
| char *buf) |
| { |
| struct most_interface *iface = to_most_interface(dev); |
| |
| return snprintf(buf, PAGE_SIZE, "%s\n", iface->description); |
| } |
| |
| static ssize_t interface_show(struct device *dev, |
| struct device_attribute *attr, |
| char *buf) |
| { |
| struct most_interface *iface = to_most_interface(dev); |
| |
| switch (iface->interface) { |
| case ITYPE_LOOPBACK: |
| return snprintf(buf, PAGE_SIZE, "loopback\n"); |
| case ITYPE_I2C: |
| return snprintf(buf, PAGE_SIZE, "i2c\n"); |
| case ITYPE_I2S: |
| return snprintf(buf, PAGE_SIZE, "i2s\n"); |
| case ITYPE_TSI: |
| return snprintf(buf, PAGE_SIZE, "tsi\n"); |
| case ITYPE_HBI: |
| return snprintf(buf, PAGE_SIZE, "hbi\n"); |
| case ITYPE_MEDIALB_DIM: |
| return snprintf(buf, PAGE_SIZE, "mlb_dim\n"); |
| case ITYPE_MEDIALB_DIM2: |
| return snprintf(buf, PAGE_SIZE, "mlb_dim2\n"); |
| case ITYPE_USB: |
| return snprintf(buf, PAGE_SIZE, "usb\n"); |
| case ITYPE_PCIE: |
| return snprintf(buf, PAGE_SIZE, "pcie\n"); |
| } |
| return snprintf(buf, PAGE_SIZE, "unknown\n"); |
| } |
| |
| static DEVICE_ATTR_RO(description); |
| static DEVICE_ATTR_RO(interface); |
| |
| static struct attribute *interface_attrs[] = { |
| DEV_ATTR(description), |
| DEV_ATTR(interface), |
| NULL, |
| }; |
| |
| static struct attribute_group interface_attr_group = { |
| .attrs = interface_attrs, |
| }; |
| |
| static const struct attribute_group *interface_attr_groups[] = { |
| &interface_attr_group, |
| NULL, |
| }; |
| |
| static struct core_component *match_component(char *name) |
| { |
| struct core_component *comp; |
| |
| list_for_each_entry(comp, &mc.comp_list, list) { |
| if (!strcmp(comp->name, name)) |
| return comp; |
| } |
| return NULL; |
| } |
| |
| struct show_links_data { |
| int offs; |
| char *buf; |
| }; |
| |
| static int print_links(struct device *dev, void *data) |
| { |
| struct show_links_data *d = data; |
| int offs = d->offs; |
| char *buf = d->buf; |
| struct most_channel *c; |
| struct most_interface *iface = to_most_interface(dev); |
| |
| list_for_each_entry(c, &iface->p->channel_list, list) { |
| if (c->pipe0.comp) { |
| offs += snprintf(buf + offs, |
| PAGE_SIZE - offs, |
| "%s:%s:%s\n", |
| c->pipe0.comp->name, |
| dev_name(&iface->dev), |
| dev_name(&c->dev)); |
| } |
| if (c->pipe1.comp) { |
| offs += snprintf(buf + offs, |
| PAGE_SIZE - offs, |
| "%s:%s:%s\n", |
| c->pipe1.comp->name, |
| dev_name(&iface->dev), |
| dev_name(&c->dev)); |
| } |
| } |
| d->offs = offs; |
| return 0; |
| } |
| |
| static ssize_t links_show(struct device_driver *drv, char *buf) |
| { |
| struct show_links_data d = { .buf = buf }; |
| |
| bus_for_each_dev(&mc.bus, NULL, &d, print_links); |
| return d.offs; |
| } |
| |
| static ssize_t components_show(struct device_driver *drv, char *buf) |
| { |
| struct core_component *comp; |
| int offs = 0; |
| |
| list_for_each_entry(comp, &mc.comp_list, list) { |
| offs += snprintf(buf + offs, PAGE_SIZE - offs, "%s\n", |
| comp->name); |
| } |
| return offs; |
| } |
| |
| /** |
| * split_string - parses buf and extracts ':' separated substrings. |
| * |
| * @buf: complete string from attribute 'add_channel' |
| * @a: storage for 1st substring (=interface name) |
| * @b: storage for 2nd substring (=channel name) |
| * @c: storage for 3rd substring (=component name) |
| * @d: storage optional 4th substring (=user defined name) |
| * |
| * Examples: |
| * |
| * Input: "mdev0:ch6:cdev:my_channel\n" or |
| * "mdev0:ch6:cdev:my_channel" |
| * |
| * Output: *a -> "mdev0", *b -> "ch6", *c -> "cdev" *d -> "my_channel" |
| * |
| * Input: "mdev1:ep81:cdev\n" |
| * Output: *a -> "mdev1", *b -> "ep81", *c -> "cdev" *d -> "" |
| * |
| * Input: "mdev1:ep81" |
| * Output: *a -> "mdev1", *b -> "ep81", *c -> "cdev" *d == NULL |
| */ |
| static int split_string(char *buf, char **a, char **b, char **c, char **d) |
| { |
| *a = strsep(&buf, ":"); |
| if (!*a) |
| return -EIO; |
| |
| *b = strsep(&buf, ":\n"); |
| if (!*b) |
| return -EIO; |
| |
| *c = strsep(&buf, ":\n"); |
| if (!*c) |
| return -EIO; |
| |
| if (d) |
| *d = strsep(&buf, ":\n"); |
| |
| return 0; |
| } |
| |
| static int match_bus_dev(struct device *dev, void *data) |
| { |
| char *mdev_name = data; |
| |
| return !strcmp(dev_name(dev), mdev_name); |
| } |
| |
| /** |
| * get_channel - get pointer to channel |
| * @mdev: name of the device interface |
| * @mdev_ch: name of channel |
| */ |
| static struct most_channel *get_channel(char *mdev, char *mdev_ch) |
| { |
| struct device *dev = NULL; |
| struct most_interface *iface; |
| struct most_channel *c, *tmp; |
| |
| dev = bus_find_device(&mc.bus, NULL, mdev, match_bus_dev); |
| if (!dev) |
| return NULL; |
| iface = to_most_interface(dev); |
| list_for_each_entry_safe(c, tmp, &iface->p->channel_list, list) { |
| if (!strcmp(dev_name(&c->dev), mdev_ch)) |
| return c; |
| } |
| return NULL; |
| } |
| |
| static |
| inline int link_channel_to_component(struct most_channel *c, |
| struct core_component *comp, |
| char *comp_param) |
| { |
| int ret; |
| struct core_component **comp_ptr; |
| |
| if (!c->pipe0.comp) |
| comp_ptr = &c->pipe0.comp; |
| else if (!c->pipe1.comp) |
| comp_ptr = &c->pipe1.comp; |
| else |
| return -ENOSPC; |
| |
| *comp_ptr = comp; |
| ret = comp->probe_channel(c->iface, c->channel_id, &c->cfg, comp_param); |
| if (ret) { |
| *comp_ptr = NULL; |
| return ret; |
| } |
| return 0; |
| } |
| |
| /** |
| * add_link_store - store function for add_link attribute |
| * @drv: device driver |
| * @buf: buffer |
| * @len: buffer length |
| * |
| * This parses the string given by buf and splits it into |
| * four substrings. Note: last substring is optional. In case a cdev |
| * component is loaded the optional 4th substring will make up the name of |
| * device node in the /dev directory. If omitted, the device node will |
| * inherit the channel's name within sysfs. |
| * |
| * Searches for (device, channel) pair and probes the component |
| * |
| * Example: |
| * (1) echo "mdev0:ch6:cdev:my_rxchannel" >add_link |
| * (2) echo "mdev1:ep81:cdev" >add_link |
| * |
| * (1) would create the device node /dev/my_rxchannel |
| * (2) would create the device node /dev/mdev1-ep81 |
| */ |
| static ssize_t add_link_store(struct device_driver *drv, |
| const char *buf, |
| size_t len) |
| { |
| struct most_channel *c; |
| struct core_component *comp; |
| char buffer[STRING_SIZE]; |
| char *mdev; |
| char *mdev_ch; |
| char *comp_name; |
| char *comp_param; |
| char devnod_buf[STRING_SIZE]; |
| int ret; |
| size_t max_len = min_t(size_t, len + 1, STRING_SIZE); |
| |
| strlcpy(buffer, buf, max_len); |
| ret = split_string(buffer, &mdev, &mdev_ch, &comp_name, &comp_param); |
| if (ret) |
| return ret; |
| comp = match_component(comp_name); |
| if (!comp) |
| return -ENODEV; |
| if (!comp_param || *comp_param == 0) { |
| snprintf(devnod_buf, sizeof(devnod_buf), "%s-%s", mdev, |
| mdev_ch); |
| comp_param = devnod_buf; |
| } |
| |
| c = get_channel(mdev, mdev_ch); |
| if (!c) |
| return -ENODEV; |
| |
| ret = link_channel_to_component(c, comp, comp_param); |
| if (ret) |
| return ret; |
| return len; |
| } |
| |
| /** |
| * remove_link_store - store function for remove_link attribute |
| * @drv: device driver |
| * @buf: buffer |
| * @len: buffer length |
| * |
| * Example: |
| * echo "mdev0:ep81" >remove_link |
| */ |
| static ssize_t remove_link_store(struct device_driver *drv, |
| const char *buf, |
| size_t len) |
| { |
| struct most_channel *c; |
| struct core_component *comp; |
| char buffer[STRING_SIZE]; |
| char *mdev; |
| char *mdev_ch; |
| char *comp_name; |
| int ret; |
| size_t max_len = min_t(size_t, len + 1, STRING_SIZE); |
| |
| strlcpy(buffer, buf, max_len); |
| ret = split_string(buffer, &mdev, &mdev_ch, &comp_name, NULL); |
| if (ret) |
| return ret; |
| comp = match_component(comp_name); |
| if (!comp) |
| return -ENODEV; |
| c = get_channel(mdev, mdev_ch); |
| if (!c) |
| return -ENODEV; |
| |
| if (comp->disconnect_channel(c->iface, c->channel_id)) |
| return -EIO; |
| if (c->pipe0.comp == comp) |
| c->pipe0.comp = NULL; |
| if (c->pipe1.comp == comp) |
| c->pipe1.comp = NULL; |
| return len; |
| } |
| |
| #define DRV_ATTR(_name) (&driver_attr_##_name.attr) |
| |
| static DRIVER_ATTR_RO(links); |
| static DRIVER_ATTR_RO(components); |
| static DRIVER_ATTR_WO(add_link); |
| static DRIVER_ATTR_WO(remove_link); |
| |
| static struct attribute *mc_attrs[] = { |
| DRV_ATTR(links), |
| DRV_ATTR(components), |
| DRV_ATTR(add_link), |
| DRV_ATTR(remove_link), |
| NULL, |
| }; |
| |
| static struct attribute_group mc_attr_group = { |
| .attrs = mc_attrs, |
| }; |
| |
| static const struct attribute_group *mc_attr_groups[] = { |
| &mc_attr_group, |
| NULL, |
| }; |
| |
| static int most_match(struct device *dev, struct device_driver *drv) |
| { |
| if (!strcmp(dev_name(dev), "most")) |
| return 0; |
| else |
| return 1; |
| } |
| |
| static inline void trash_mbo(struct mbo *mbo) |
| { |
| unsigned long flags; |
| struct most_channel *c = mbo->context; |
| |
| spin_lock_irqsave(&c->fifo_lock, flags); |
| list_add(&mbo->list, &c->trash_fifo); |
| spin_unlock_irqrestore(&c->fifo_lock, flags); |
| } |
| |
| static bool hdm_mbo_ready(struct most_channel *c) |
| { |
| bool empty; |
| |
| if (c->enqueue_halt) |
| return false; |
| |
| spin_lock_irq(&c->fifo_lock); |
| empty = list_empty(&c->halt_fifo); |
| spin_unlock_irq(&c->fifo_lock); |
| |
| return !empty; |
| } |
| |
| static void nq_hdm_mbo(struct mbo *mbo) |
| { |
| unsigned long flags; |
| struct most_channel *c = mbo->context; |
| |
| spin_lock_irqsave(&c->fifo_lock, flags); |
| list_add_tail(&mbo->list, &c->halt_fifo); |
| spin_unlock_irqrestore(&c->fifo_lock, flags); |
| wake_up_interruptible(&c->hdm_fifo_wq); |
| } |
| |
| static int hdm_enqueue_thread(void *data) |
| { |
| struct most_channel *c = data; |
| struct mbo *mbo; |
| int ret; |
| typeof(c->iface->enqueue) enqueue = c->iface->enqueue; |
| |
| while (likely(!kthread_should_stop())) { |
| wait_event_interruptible(c->hdm_fifo_wq, |
| hdm_mbo_ready(c) || |
| kthread_should_stop()); |
| |
| mutex_lock(&c->nq_mutex); |
| spin_lock_irq(&c->fifo_lock); |
| if (unlikely(c->enqueue_halt || list_empty(&c->halt_fifo))) { |
| spin_unlock_irq(&c->fifo_lock); |
| mutex_unlock(&c->nq_mutex); |
| continue; |
| } |
| |
| mbo = list_pop_mbo(&c->halt_fifo); |
| spin_unlock_irq(&c->fifo_lock); |
| |
| if (c->cfg.direction == MOST_CH_RX) |
| mbo->buffer_length = c->cfg.buffer_size; |
| |
| ret = enqueue(mbo->ifp, mbo->hdm_channel_id, mbo); |
| mutex_unlock(&c->nq_mutex); |
| |
| if (unlikely(ret)) { |
| pr_err("hdm enqueue failed\n"); |
| nq_hdm_mbo(mbo); |
| c->hdm_enqueue_task = NULL; |
| return 0; |
| } |
| } |
| |
| return 0; |
| } |
| |
| static int run_enqueue_thread(struct most_channel *c, int channel_id) |
| { |
| struct task_struct *task = |
| kthread_run(hdm_enqueue_thread, c, "hdm_fifo_%d", |
| channel_id); |
| |
| if (IS_ERR(task)) |
| return PTR_ERR(task); |
| |
| c->hdm_enqueue_task = task; |
| return 0; |
| } |
| |
| /** |
| * arm_mbo - recycle MBO for further usage |
| * @mbo: most buffer |
| * |
| * This puts an MBO back to the list to have it ready for up coming |
| * tx transactions. |
| * |
| * In case the MBO belongs to a channel that recently has been |
| * poisoned, the MBO is scheduled to be trashed. |
| * Calls the completion handler of an attached component. |
| */ |
| static void arm_mbo(struct mbo *mbo) |
| { |
| unsigned long flags; |
| struct most_channel *c; |
| |
| c = mbo->context; |
| |
| if (c->is_poisoned) { |
| trash_mbo(mbo); |
| return; |
| } |
| |
| spin_lock_irqsave(&c->fifo_lock, flags); |
| ++*mbo->num_buffers_ptr; |
| list_add_tail(&mbo->list, &c->fifo); |
| spin_unlock_irqrestore(&c->fifo_lock, flags); |
| |
| if (c->pipe0.refs && c->pipe0.comp->tx_completion) |
| c->pipe0.comp->tx_completion(c->iface, c->channel_id); |
| |
| if (c->pipe1.refs && c->pipe1.comp->tx_completion) |
| c->pipe1.comp->tx_completion(c->iface, c->channel_id); |
| } |
| |
| /** |
| * arm_mbo_chain - helper function that arms an MBO chain for the HDM |
| * @c: pointer to interface channel |
| * @dir: direction of the channel |
| * @compl: pointer to completion function |
| * |
| * This allocates buffer objects including the containing DMA coherent |
| * buffer and puts them in the fifo. |
| * Buffers of Rx channels are put in the kthread fifo, hence immediately |
| * submitted to the HDM. |
| * |
| * Returns the number of allocated and enqueued MBOs. |
| */ |
| static int arm_mbo_chain(struct most_channel *c, int dir, |
| void (*compl)(struct mbo *)) |
| { |
| unsigned int i; |
| struct mbo *mbo; |
| unsigned long flags; |
| u32 coherent_buf_size = c->cfg.buffer_size + c->cfg.extra_len; |
| |
| atomic_set(&c->mbo_nq_level, 0); |
| |
| for (i = 0; i < c->cfg.num_buffers; i++) { |
| mbo = kzalloc(sizeof(*mbo), GFP_KERNEL); |
| if (!mbo) |
| goto flush_fifos; |
| |
| mbo->context = c; |
| mbo->ifp = c->iface; |
| mbo->hdm_channel_id = c->channel_id; |
| if (c->iface->dma_alloc) { |
| mbo->virt_address = |
| c->iface->dma_alloc(mbo, coherent_buf_size); |
| } else { |
| mbo->virt_address = |
| kzalloc(coherent_buf_size, GFP_KERNEL); |
| } |
| if (!mbo->virt_address) |
| goto release_mbo; |
| |
| mbo->complete = compl; |
| mbo->num_buffers_ptr = &dummy_num_buffers; |
| if (dir == MOST_CH_RX) { |
| nq_hdm_mbo(mbo); |
| atomic_inc(&c->mbo_nq_level); |
| } else { |
| spin_lock_irqsave(&c->fifo_lock, flags); |
| list_add_tail(&mbo->list, &c->fifo); |
| spin_unlock_irqrestore(&c->fifo_lock, flags); |
| } |
| } |
| return c->cfg.num_buffers; |
| |
| release_mbo: |
| kfree(mbo); |
| |
| flush_fifos: |
| flush_channel_fifos(c); |
| return 0; |
| } |
| |
| /** |
| * most_submit_mbo - submits an MBO to fifo |
| * @mbo: most buffer |
| */ |
| void most_submit_mbo(struct mbo *mbo) |
| { |
| if (WARN_ONCE(!mbo || !mbo->context, |
| "bad mbo or missing channel reference\n")) |
| return; |
| |
| nq_hdm_mbo(mbo); |
| } |
| EXPORT_SYMBOL_GPL(most_submit_mbo); |
| |
| /** |
| * most_write_completion - write completion handler |
| * @mbo: most buffer |
| * |
| * This recycles the MBO for further usage. In case the channel has been |
| * poisoned, the MBO is scheduled to be trashed. |
| */ |
| static void most_write_completion(struct mbo *mbo) |
| { |
| struct most_channel *c; |
| |
| c = mbo->context; |
| if (mbo->status == MBO_E_INVAL) |
| pr_info("WARN: Tx MBO status: invalid\n"); |
| if (unlikely(c->is_poisoned || (mbo->status == MBO_E_CLOSE))) |
| trash_mbo(mbo); |
| else |
| arm_mbo(mbo); |
| } |
| |
| int channel_has_mbo(struct most_interface *iface, int id, |
| struct core_component *comp) |
| { |
| struct most_channel *c = iface->p->channel[id]; |
| unsigned long flags; |
| int empty; |
| |
| if (unlikely(!c)) |
| return -EINVAL; |
| |
| if (c->pipe0.refs && c->pipe1.refs && |
| ((comp == c->pipe0.comp && c->pipe0.num_buffers <= 0) || |
| (comp == c->pipe1.comp && c->pipe1.num_buffers <= 0))) |
| return 0; |
| |
| spin_lock_irqsave(&c->fifo_lock, flags); |
| empty = list_empty(&c->fifo); |
| spin_unlock_irqrestore(&c->fifo_lock, flags); |
| return !empty; |
| } |
| EXPORT_SYMBOL_GPL(channel_has_mbo); |
| |
| /** |
| * most_get_mbo - get pointer to an MBO of pool |
| * @iface: pointer to interface instance |
| * @id: channel ID |
| * @comp: driver component |
| * |
| * This attempts to get a free buffer out of the channel fifo. |
| * Returns a pointer to MBO on success or NULL otherwise. |
| */ |
| struct mbo *most_get_mbo(struct most_interface *iface, int id, |
| struct core_component *comp) |
| { |
| struct mbo *mbo; |
| struct most_channel *c; |
| unsigned long flags; |
| int *num_buffers_ptr; |
| |
| c = iface->p->channel[id]; |
| if (unlikely(!c)) |
| return NULL; |
| |
| if (c->pipe0.refs && c->pipe1.refs && |
| ((comp == c->pipe0.comp && c->pipe0.num_buffers <= 0) || |
| (comp == c->pipe1.comp && c->pipe1.num_buffers <= 0))) |
| return NULL; |
| |
| if (comp == c->pipe0.comp) |
| num_buffers_ptr = &c->pipe0.num_buffers; |
| else if (comp == c->pipe1.comp) |
| num_buffers_ptr = &c->pipe1.num_buffers; |
| else |
| num_buffers_ptr = &dummy_num_buffers; |
| |
| spin_lock_irqsave(&c->fifo_lock, flags); |
| if (list_empty(&c->fifo)) { |
| spin_unlock_irqrestore(&c->fifo_lock, flags); |
| return NULL; |
| } |
| mbo = list_pop_mbo(&c->fifo); |
| --*num_buffers_ptr; |
| spin_unlock_irqrestore(&c->fifo_lock, flags); |
| |
| mbo->num_buffers_ptr = num_buffers_ptr; |
| mbo->buffer_length = c->cfg.buffer_size; |
| return mbo; |
| } |
| EXPORT_SYMBOL_GPL(most_get_mbo); |
| |
| /** |
| * most_put_mbo - return buffer to pool |
| * @mbo: most buffer |
| */ |
| void most_put_mbo(struct mbo *mbo) |
| { |
| struct most_channel *c = mbo->context; |
| |
| if (c->cfg.direction == MOST_CH_TX) { |
| arm_mbo(mbo); |
| return; |
| } |
| nq_hdm_mbo(mbo); |
| atomic_inc(&c->mbo_nq_level); |
| } |
| EXPORT_SYMBOL_GPL(most_put_mbo); |
| |
| /** |
| * most_read_completion - read completion handler |
| * @mbo: most buffer |
| * |
| * This function is called by the HDM when data has been received from the |
| * hardware and copied to the buffer of the MBO. |
| * |
| * In case the channel has been poisoned it puts the buffer in the trash queue. |
| * Otherwise, it passes the buffer to an component for further processing. |
| */ |
| static void most_read_completion(struct mbo *mbo) |
| { |
| struct most_channel *c = mbo->context; |
| |
| if (unlikely(c->is_poisoned || (mbo->status == MBO_E_CLOSE))) { |
| trash_mbo(mbo); |
| return; |
| } |
| |
| if (mbo->status == MBO_E_INVAL) { |
| nq_hdm_mbo(mbo); |
| atomic_inc(&c->mbo_nq_level); |
| return; |
| } |
| |
| if (atomic_sub_and_test(1, &c->mbo_nq_level)) |
| c->is_starving = 1; |
| |
| if (c->pipe0.refs && c->pipe0.comp->rx_completion && |
| c->pipe0.comp->rx_completion(mbo) == 0) |
| return; |
| |
| if (c->pipe1.refs && c->pipe1.comp->rx_completion && |
| c->pipe1.comp->rx_completion(mbo) == 0) |
| return; |
| |
| most_put_mbo(mbo); |
| } |
| |
| /** |
| * most_start_channel - prepares a channel for communication |
| * @iface: pointer to interface instance |
| * @id: channel ID |
| * @comp: driver component |
| * |
| * This prepares the channel for usage. Cross-checks whether the |
| * channel's been properly configured. |
| * |
| * Returns 0 on success or error code otherwise. |
| */ |
| int most_start_channel(struct most_interface *iface, int id, |
| struct core_component *comp) |
| { |
| int num_buffer; |
| int ret; |
| struct most_channel *c = iface->p->channel[id]; |
| |
| if (unlikely(!c)) |
| return -EINVAL; |
| |
| mutex_lock(&c->start_mutex); |
| if (c->pipe0.refs + c->pipe1.refs > 0) |
| goto out; /* already started by another component */ |
| |
| if (!try_module_get(iface->mod)) { |
| pr_info("failed to acquire HDM lock\n"); |
| mutex_unlock(&c->start_mutex); |
| return -ENOLCK; |
| } |
| |
| c->cfg.extra_len = 0; |
| if (c->iface->configure(c->iface, c->channel_id, &c->cfg)) { |
| pr_info("channel configuration failed. Go check settings...\n"); |
| ret = -EINVAL; |
| goto err_put_module; |
| } |
| |
| init_waitqueue_head(&c->hdm_fifo_wq); |
| |
| if (c->cfg.direction == MOST_CH_RX) |
| num_buffer = arm_mbo_chain(c, c->cfg.direction, |
| most_read_completion); |
| else |
| num_buffer = arm_mbo_chain(c, c->cfg.direction, |
| most_write_completion); |
| if (unlikely(!num_buffer)) { |
| ret = -ENOMEM; |
| goto err_put_module; |
| } |
| |
| ret = run_enqueue_thread(c, id); |
| if (ret) |
| goto err_put_module; |
| |
| c->is_starving = 0; |
| c->pipe0.num_buffers = c->cfg.num_buffers / 2; |
| c->pipe1.num_buffers = c->cfg.num_buffers - c->pipe0.num_buffers; |
| atomic_set(&c->mbo_ref, num_buffer); |
| |
| out: |
| if (comp == c->pipe0.comp) |
| c->pipe0.refs++; |
| if (comp == c->pipe1.comp) |
| c->pipe1.refs++; |
| mutex_unlock(&c->start_mutex); |
| return 0; |
| |
| err_put_module: |
| module_put(iface->mod); |
| mutex_unlock(&c->start_mutex); |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(most_start_channel); |
| |
| /** |
| * most_stop_channel - stops a running channel |
| * @iface: pointer to interface instance |
| * @id: channel ID |
| * @comp: driver component |
| */ |
| int most_stop_channel(struct most_interface *iface, int id, |
| struct core_component *comp) |
| { |
| struct most_channel *c; |
| |
| if (unlikely((!iface) || (id >= iface->num_channels) || (id < 0))) { |
| pr_err("Bad interface or index out of range\n"); |
| return -EINVAL; |
| } |
| c = iface->p->channel[id]; |
| if (unlikely(!c)) |
| return -EINVAL; |
| |
| mutex_lock(&c->start_mutex); |
| if (c->pipe0.refs + c->pipe1.refs >= 2) |
| goto out; |
| |
| if (c->hdm_enqueue_task) |
| kthread_stop(c->hdm_enqueue_task); |
| c->hdm_enqueue_task = NULL; |
| |
| if (iface->mod) |
| module_put(iface->mod); |
| |
| c->is_poisoned = true; |
| if (c->iface->poison_channel(c->iface, c->channel_id)) { |
| pr_err("Cannot stop channel %d of mdev %s\n", c->channel_id, |
| c->iface->description); |
| mutex_unlock(&c->start_mutex); |
| return -EAGAIN; |
| } |
| flush_trash_fifo(c); |
| flush_channel_fifos(c); |
| |
| #ifdef CMPL_INTERRUPTIBLE |
| if (wait_for_completion_interruptible(&c->cleanup)) { |
| pr_info("Interrupted while clean up ch %d\n", c->channel_id); |
| mutex_unlock(&c->start_mutex); |
| return -EINTR; |
| } |
| #else |
| wait_for_completion(&c->cleanup); |
| #endif |
| c->is_poisoned = false; |
| |
| out: |
| if (comp == c->pipe0.comp) |
| c->pipe0.refs--; |
| if (comp == c->pipe1.comp) |
| c->pipe1.refs--; |
| mutex_unlock(&c->start_mutex); |
| return 0; |
| } |
| EXPORT_SYMBOL_GPL(most_stop_channel); |
| |
| /** |
| * most_register_component - registers a driver component with the core |
| * @comp: driver component |
| */ |
| int most_register_component(struct core_component *comp) |
| { |
| if (!comp) { |
| pr_err("Bad component\n"); |
| return -EINVAL; |
| } |
| list_add_tail(&comp->list, &mc.comp_list); |
| pr_info("registered new core component %s\n", comp->name); |
| return 0; |
| } |
| EXPORT_SYMBOL_GPL(most_register_component); |
| |
| static int disconnect_channels(struct device *dev, void *data) |
| { |
| struct most_interface *iface; |
| struct most_channel *c, *tmp; |
| struct core_component *comp = data; |
| |
| iface = to_most_interface(dev); |
| list_for_each_entry_safe(c, tmp, &iface->p->channel_list, list) { |
| if (c->pipe0.comp == comp || c->pipe1.comp == comp) |
| comp->disconnect_channel(c->iface, c->channel_id); |
| if (c->pipe0.comp == comp) |
| c->pipe0.comp = NULL; |
| if (c->pipe1.comp == comp) |
| c->pipe1.comp = NULL; |
| } |
| return 0; |
| } |
| |
| /** |
| * most_deregister_component - deregisters a driver component with the core |
| * @comp: driver component |
| */ |
| int most_deregister_component(struct core_component *comp) |
| { |
| if (!comp) { |
| pr_err("Bad component\n"); |
| return -EINVAL; |
| } |
| |
| bus_for_each_dev(&mc.bus, NULL, comp, disconnect_channels); |
| list_del(&comp->list); |
| pr_info("deregistering component %s\n", comp->name); |
| return 0; |
| } |
| EXPORT_SYMBOL_GPL(most_deregister_component); |
| |
| static void release_interface(struct device *dev) |
| { |
| pr_info("releasing interface dev %s...\n", dev_name(dev)); |
| } |
| |
| static void release_channel(struct device *dev) |
| { |
| pr_info("releasing channel dev %s...\n", dev_name(dev)); |
| } |
| |
| /** |
| * most_register_interface - registers an interface with core |
| * @iface: device interface |
| * |
| * Allocates and initializes a new interface instance and all of its channels. |
| * Returns a pointer to kobject or an error pointer. |
| */ |
| int most_register_interface(struct most_interface *iface) |
| { |
| unsigned int i; |
| int id; |
| struct most_channel *c; |
| |
| if (!iface || !iface->enqueue || !iface->configure || |
| !iface->poison_channel || (iface->num_channels > MAX_CHANNELS)) { |
| pr_err("Bad interface or channel overflow\n"); |
| return -EINVAL; |
| } |
| |
| id = ida_simple_get(&mdev_id, 0, 0, GFP_KERNEL); |
| if (id < 0) { |
| pr_info("Failed to alloc mdev ID\n"); |
| return id; |
| } |
| |
| iface->p = kzalloc(sizeof(*iface->p), GFP_KERNEL); |
| if (!iface->p) { |
| ida_simple_remove(&mdev_id, id); |
| return -ENOMEM; |
| } |
| |
| INIT_LIST_HEAD(&iface->p->channel_list); |
| iface->p->dev_id = id; |
| strcpy(iface->p->name, iface->description); |
| iface->dev.init_name = iface->p->name; |
| iface->dev.bus = &mc.bus; |
| iface->dev.parent = &mc.dev; |
| iface->dev.groups = interface_attr_groups; |
| iface->dev.release = release_interface; |
| if (device_register(&iface->dev)) { |
| pr_err("registering iface->dev failed\n"); |
| kfree(iface->p); |
| ida_simple_remove(&mdev_id, id); |
| return -ENOMEM; |
| } |
| |
| for (i = 0; i < iface->num_channels; i++) { |
| const char *name_suffix = iface->channel_vector[i].name_suffix; |
| |
| c = kzalloc(sizeof(*c), GFP_KERNEL); |
| if (!c) |
| goto err_free_resources; |
| if (!name_suffix) |
| snprintf(c->name, STRING_SIZE, "ch%d", i); |
| else |
| snprintf(c->name, STRING_SIZE, "%s", name_suffix); |
| c->dev.init_name = c->name; |
| c->dev.parent = &iface->dev; |
| c->dev.groups = channel_attr_groups; |
| c->dev.release = release_channel; |
| iface->p->channel[i] = c; |
| c->is_starving = 0; |
| c->iface = iface; |
| c->channel_id = i; |
| c->keep_mbo = false; |
| c->enqueue_halt = false; |
| c->is_poisoned = false; |
| c->cfg.direction = 0; |
| c->cfg.data_type = 0; |
| c->cfg.num_buffers = 0; |
| c->cfg.buffer_size = 0; |
| c->cfg.subbuffer_size = 0; |
| c->cfg.packets_per_xact = 0; |
| spin_lock_init(&c->fifo_lock); |
| INIT_LIST_HEAD(&c->fifo); |
| INIT_LIST_HEAD(&c->trash_fifo); |
| INIT_LIST_HEAD(&c->halt_fifo); |
| init_completion(&c->cleanup); |
| atomic_set(&c->mbo_ref, 0); |
| mutex_init(&c->start_mutex); |
| mutex_init(&c->nq_mutex); |
| list_add_tail(&c->list, &iface->p->channel_list); |
| if (device_register(&c->dev)) { |
| pr_err("registering c->dev failed\n"); |
| goto err_free_most_channel; |
| } |
| } |
| pr_info("registered new device mdev%d (%s)\n", |
| id, iface->description); |
| return 0; |
| |
| err_free_most_channel: |
| kfree(c); |
| |
| err_free_resources: |
| while (i > 0) { |
| c = iface->p->channel[--i]; |
| device_unregister(&c->dev); |
| kfree(c); |
| } |
| kfree(iface->p); |
| device_unregister(&iface->dev); |
| ida_simple_remove(&mdev_id, id); |
| return -ENOMEM; |
| } |
| EXPORT_SYMBOL_GPL(most_register_interface); |
| |
| /** |
| * most_deregister_interface - deregisters an interface with core |
| * @iface: device interface |
| * |
| * Before removing an interface instance from the list, all running |
| * channels are stopped and poisoned. |
| */ |
| void most_deregister_interface(struct most_interface *iface) |
| { |
| int i; |
| struct most_channel *c; |
| |
| pr_info("deregistering device %s (%s)\n", dev_name(&iface->dev), |
| iface->description); |
| for (i = 0; i < iface->num_channels; i++) { |
| c = iface->p->channel[i]; |
| if (c->pipe0.comp) |
| c->pipe0.comp->disconnect_channel(c->iface, |
| c->channel_id); |
| if (c->pipe1.comp) |
| c->pipe1.comp->disconnect_channel(c->iface, |
| c->channel_id); |
| c->pipe0.comp = NULL; |
| c->pipe1.comp = NULL; |
| list_del(&c->list); |
| device_unregister(&c->dev); |
| kfree(c); |
| } |
| |
| ida_simple_remove(&mdev_id, iface->p->dev_id); |
| kfree(iface->p); |
| device_unregister(&iface->dev); |
| } |
| EXPORT_SYMBOL_GPL(most_deregister_interface); |
| |
| /** |
| * most_stop_enqueue - prevents core from enqueueing MBOs |
| * @iface: pointer to interface |
| * @id: channel id |
| * |
| * This is called by an HDM that _cannot_ attend to its duties and |
| * is imminent to get run over by the core. The core is not going to |
| * enqueue any further packets unless the flagging HDM calls |
| * most_resume enqueue(). |
| */ |
| void most_stop_enqueue(struct most_interface *iface, int id) |
| { |
| struct most_channel *c = iface->p->channel[id]; |
| |
| if (!c) |
| return; |
| |
| mutex_lock(&c->nq_mutex); |
| c->enqueue_halt = true; |
| mutex_unlock(&c->nq_mutex); |
| } |
| EXPORT_SYMBOL_GPL(most_stop_enqueue); |
| |
| /** |
| * most_resume_enqueue - allow core to enqueue MBOs again |
| * @iface: pointer to interface |
| * @id: channel id |
| * |
| * This clears the enqueue halt flag and enqueues all MBOs currently |
| * sitting in the wait fifo. |
| */ |
| void most_resume_enqueue(struct most_interface *iface, int id) |
| { |
| struct most_channel *c = iface->p->channel[id]; |
| |
| if (!c) |
| return; |
| |
| mutex_lock(&c->nq_mutex); |
| c->enqueue_halt = false; |
| mutex_unlock(&c->nq_mutex); |
| |
| wake_up_interruptible(&c->hdm_fifo_wq); |
| } |
| EXPORT_SYMBOL_GPL(most_resume_enqueue); |
| |
| static void release_most_sub(struct device *dev) |
| { |
| pr_info("releasing most_subsystem\n"); |
| } |
| |
| static int __init most_init(void) |
| { |
| int err; |
| |
| pr_info("init()\n"); |
| INIT_LIST_HEAD(&mc.comp_list); |
| ida_init(&mdev_id); |
| |
| mc.bus.name = "most", |
| mc.bus.match = most_match, |
| mc.drv.name = "most_core", |
| mc.drv.bus = &mc.bus, |
| mc.drv.groups = mc_attr_groups; |
| |
| err = bus_register(&mc.bus); |
| if (err) { |
| pr_info("Cannot register most bus\n"); |
| return err; |
| } |
| err = driver_register(&mc.drv); |
| if (err) { |
| pr_info("Cannot register core driver\n"); |
| goto err_unregister_bus; |
| } |
| mc.dev.init_name = "most_bus"; |
| mc.dev.release = release_most_sub; |
| if (device_register(&mc.dev)) { |
| err = -ENOMEM; |
| goto err_unregister_driver; |
| } |
| |
| return 0; |
| |
| err_unregister_driver: |
| driver_unregister(&mc.drv); |
| err_unregister_bus: |
| bus_unregister(&mc.bus); |
| return err; |
| } |
| |
| static void __exit most_exit(void) |
| { |
| pr_info("exit core module\n"); |
| device_unregister(&mc.dev); |
| driver_unregister(&mc.drv); |
| bus_unregister(&mc.bus); |
| ida_destroy(&mdev_id); |
| } |
| |
| module_init(most_init); |
| module_exit(most_exit); |
| MODULE_LICENSE("GPL"); |
| MODULE_AUTHOR("Christian Gromm <christian.gromm@microchip.com>"); |
| MODULE_DESCRIPTION("Core module of stacked MOST Linux driver"); |