| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Christian Gromm | 6985 | 97.84% | 64 | 80.00% |
| Andrey Shvetsov | 73 | 1.02% | 5 | 6.25% |
| Hari Prasath Gujulan Elango | 38 | 0.53% | 1 | 1.25% |
| Sudip Mukherjee | 19 | 0.27% | 1 | 1.25% |
| Gustavo A. R. Silva | 10 | 0.14% | 1 | 1.25% |
| Rikard Falkeborn | 3 | 0.04% | 1 | 1.25% |
| Takashi Iwai | 3 | 0.04% | 1 | 1.25% |
| Colin Ian King | 2 | 0.03% | 1 | 1.25% |
| Adrian Remonda | 2 | 0.03% | 1 | 1.25% |
| Ricardo B. Marliere | 1 | 0.01% | 1 | 1.25% |
| Kees Cook | 1 | 0.01% | 1 | 1.25% |
| Greg Kroah-Hartman | 1 | 0.01% | 1 | 1.25% |
| Suzuki K. Poulose | 1 | 0.01% | 1 | 1.25% |
| Total | 7139 | 80 |
// SPDX-License-Identifier: GPL-2.0 /* * core.c - Implementation of core module of MOST Linux driver stack * * Copyright (C) 2013-2020 Microchip Technology Germany II GmbH & Co. KG */ #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 <linux/most.h> #define MAX_CHANNELS 64 #define STRING_SIZE 80 static struct ida mdev_id; static int dummy_num_buffers; static struct list_head comp_list; struct pipe { struct most_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; /* channel activation synchronization */ 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; /* fifo access synchronization */ 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" }, { MOST_CH_ASYNC, "async" }, { MOST_CH_SYNC, "sync" }, { MOST_CH_ISOC, "isoc"}, { MOST_CH_ISOC, "isoc_avp"}, }; /** * 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)))) dev_warn(&c->dev, "Channel or 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_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_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_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_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_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_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); } #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_RO(set_buffer_size); static DEVICE_ATTR_RO(set_number_of_buffers); static DEVICE_ATTR_RO(set_direction); static DEVICE_ATTR_RO(set_datatype); static DEVICE_ATTR_RO(set_subbuffer_size); static DEVICE_ATTR_RO(set_packets_per_xact); static DEVICE_ATTR_RO(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 const 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 = dev_get_drvdata(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 = dev_get_drvdata(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 const struct attribute_group interface_attr_group = { .attrs = interface_attrs, }; static const struct attribute_group *interface_attr_groups[] = { &interface_attr_group, NULL, }; static struct most_component *match_component(char *name) { struct most_component *comp; list_for_each_entry(comp, &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 = dev_get_drvdata(dev); list_for_each_entry(c, &iface->p->channel_list, list) { if (c->pipe0.comp) { offs += scnprintf(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 += scnprintf(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 int most_match(struct device *dev, struct device_driver *drv) { if (!strcmp(dev_name(dev), "most")) return 0; else return 1; } static const struct bus_type mostbus = { .name = "most", .match = most_match, }; static ssize_t links_show(struct device_driver *drv, char *buf) { struct show_links_data d = { .buf = buf }; bus_for_each_dev(&mostbus, NULL, &d, print_links); return d.offs; } static ssize_t components_show(struct device_driver *drv, char *buf) { struct most_component *comp; int offs = 0; list_for_each_entry(comp, &comp_list, list) { offs += scnprintf(buf + offs, PAGE_SIZE - offs, "%s\n", comp->name); } return offs; } /** * 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_by_name(&mostbus, NULL, mdev); if (!dev) return NULL; put_device(dev); iface = dev_get_drvdata(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 most_component *comp, char *name, char *comp_param) { int ret; struct most_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, name, comp_param); if (ret) { *comp_ptr = NULL; return ret; } return 0; } int most_set_cfg_buffer_size(char *mdev, char *mdev_ch, u16 val) { struct most_channel *c = get_channel(mdev, mdev_ch); if (!c) return -ENODEV; c->cfg.buffer_size = val; return 0; } int most_set_cfg_subbuffer_size(char *mdev, char *mdev_ch, u16 val) { struct most_channel *c = get_channel(mdev, mdev_ch); if (!c) return -ENODEV; c->cfg.subbuffer_size = val; return 0; } int most_set_cfg_dbr_size(char *mdev, char *mdev_ch, u16 val) { struct most_channel *c = get_channel(mdev, mdev_ch); if (!c) return -ENODEV; c->cfg.dbr_size = val; return 0; } int most_set_cfg_num_buffers(char *mdev, char *mdev_ch, u16 val) { struct most_channel *c = get_channel(mdev, mdev_ch); if (!c) return -ENODEV; c->cfg.num_buffers = val; return 0; } int most_set_cfg_datatype(char *mdev, char *mdev_ch, char *buf) { int i; struct most_channel *c = get_channel(mdev, mdev_ch); if (!c) return -ENODEV; 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)) dev_warn(&c->dev, "Invalid attribute settings\n"); return 0; } int most_set_cfg_direction(char *mdev, char *mdev_ch, char *buf) { struct most_channel *c = get_channel(mdev, mdev_ch); if (!c) return -ENODEV; if (!strcmp(buf, "dir_rx")) { c->cfg.direction = MOST_CH_RX; } else if (!strcmp(buf, "rx")) { c->cfg.direction = MOST_CH_RX; } else if (!strcmp(buf, "dir_tx")) { c->cfg.direction = MOST_CH_TX; } else if (!strcmp(buf, "tx")) { c->cfg.direction = MOST_CH_TX; } else { dev_err(&c->dev, "Invalid direction\n"); return -ENODATA; } return 0; } int most_set_cfg_packets_xact(char *mdev, char *mdev_ch, u16 val) { struct most_channel *c = get_channel(mdev, mdev_ch); if (!c) return -ENODEV; c->cfg.packets_per_xact = val; return 0; } int most_cfg_complete(char *comp_name) { struct most_component *comp; comp = match_component(comp_name); if (!comp) return -ENODEV; return comp->cfg_complete(); } int most_add_link(char *mdev, char *mdev_ch, char *comp_name, char *link_name, char *comp_param) { struct most_channel *c = get_channel(mdev, mdev_ch); struct most_component *comp = match_component(comp_name); if (!c || !comp) return -ENODEV; return link_channel_to_component(c, comp, link_name, comp_param); } int most_remove_link(char *mdev, char *mdev_ch, char *comp_name) { struct most_channel *c; struct most_component *comp; 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 0; } #define DRV_ATTR(_name) (&driver_attr_##_name.attr) static DRIVER_ATTR_RO(links); static DRIVER_ATTR_RO(components); static struct attribute *mc_attrs[] = { DRV_ATTR(links), DRV_ATTR(components), NULL, }; static const struct attribute_group mc_attr_group = { .attrs = mc_attrs, }; static const struct attribute_group *mc_attr_groups[] = { &mc_attr_group, NULL, }; static struct device_driver mostbus_driver = { .name = "most_core", .bus = &mostbus, .groups = mc_attr_groups, }; 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)) { dev_err(&c->dev, "Buffer 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 buffer 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 (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 most_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 most_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 most_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)) { dev_err(&c->dev, "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)) { dev_err(&c->dev, "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 most_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)) { dev_err(&c->dev, "Failed to stop channel %d of interface %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)) { dev_err(&c->dev, "Interrupted while cleaning up channel %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 most_component *comp) { if (!comp) { pr_err("Bad component\n"); return -EINVAL; } list_add_tail(&comp->list, &comp_list); 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 most_component *comp = data; iface = dev_get_drvdata(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 most_component *comp) { if (!comp) { pr_err("Bad component\n"); return -EINVAL; } bus_for_each_dev(&mostbus, NULL, comp, disconnect_channels); list_del(&comp->list); return 0; } EXPORT_SYMBOL_GPL(most_deregister_component); static void release_channel(struct device *dev) { struct most_channel *c = to_channel(dev); kfree(c); } /** * 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)) return -EINVAL; id = ida_simple_get(&mdev_id, 0, 0, GFP_KERNEL); if (id < 0) { dev_err(iface->dev, "Failed to allocate device 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; strscpy(iface->p->name, iface->description, sizeof(iface->p->name)); iface->dev->bus = &mostbus; iface->dev->groups = interface_attr_groups; dev_set_drvdata(iface->dev, iface); if (device_register(iface->dev)) { dev_err(iface->dev, "Failed to register interface device\n"); kfree(iface->p); put_device(iface->dev); 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)) { dev_err(&c->dev, "Failed to register channel device\n"); goto err_free_most_channel; } } most_interface_register_notify(iface->description); return 0; err_free_most_channel: put_device(&c->dev); err_free_resources: while (i > 0) { c = iface->p->channel[--i]; device_unregister(&c->dev); } 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; 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); } 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 int __init most_init(void) { int err; INIT_LIST_HEAD(&comp_list); ida_init(&mdev_id); err = bus_register(&mostbus); if (err) { pr_err("Failed to register most bus\n"); return err; } err = driver_register(&mostbus_driver); if (err) { pr_err("Failed to register core driver\n"); goto err_unregister_bus; } configfs_init(); return 0; err_unregister_bus: bus_unregister(&mostbus); return err; } static void __exit most_exit(void) { driver_unregister(&mostbus_driver); bus_unregister(&mostbus); ida_destroy(&mdev_id); } subsys_initcall(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");
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