| /* |
| module/drivers.c |
| functions for manipulating drivers |
| |
| COMEDI - Linux Control and Measurement Device Interface |
| Copyright (C) 1997-2000 David A. Schleef <ds@schleef.org> |
| |
| This program is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2 of the License, or |
| (at your option) any later version. |
| |
| This program is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| GNU General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with this program; if not, write to the Free Software |
| Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| |
| */ |
| |
| #define _GNU_SOURCE |
| |
| #define __NO_VERSION__ |
| #include "comedi_fops.h" |
| #include <linux/device.h> |
| #include <linux/module.h> |
| #include <linux/pci.h> |
| #include <linux/usb.h> |
| #include <linux/errno.h> |
| #include <linux/kernel.h> |
| #include <linux/sched.h> |
| #include <linux/fcntl.h> |
| #include <linux/delay.h> |
| #include <linux/ioport.h> |
| #include <linux/mm.h> |
| #include <linux/slab.h> |
| #include "comedidev.h" |
| #include "wrapper.h" |
| #include <linux/highmem.h> /* for SuSE brokenness */ |
| #include <linux/vmalloc.h> |
| #include <linux/cdev.h> |
| #include <linux/dma-mapping.h> |
| |
| #include <asm/io.h> |
| #include <asm/system.h> |
| |
| static int postconfig(struct comedi_device *dev); |
| static int insn_rw_emulate_bits(struct comedi_device *dev, struct comedi_subdevice *s, |
| struct comedi_insn *insn, unsigned int *data); |
| static void *comedi_recognize(struct comedi_driver * driv, const char *name); |
| static void comedi_report_boards(struct comedi_driver *driv); |
| static int poll_invalid(struct comedi_device *dev, struct comedi_subdevice *s); |
| int comedi_buf_alloc(struct comedi_device *dev, struct comedi_subdevice *s, |
| unsigned long new_size); |
| |
| struct comedi_driver *comedi_drivers; |
| |
| int comedi_modprobe(int minor) |
| { |
| return -EINVAL; |
| } |
| |
| static void cleanup_device(struct comedi_device *dev) |
| { |
| int i; |
| struct comedi_subdevice *s; |
| |
| if (dev->subdevices) { |
| for (i = 0; i < dev->n_subdevices; i++) { |
| s = dev->subdevices + i; |
| comedi_free_subdevice_minor(s); |
| if (s->async) { |
| comedi_buf_alloc(dev, s, 0); |
| kfree(s->async); |
| } |
| } |
| kfree(dev->subdevices); |
| dev->subdevices = NULL; |
| dev->n_subdevices = 0; |
| } |
| kfree(dev->private); |
| dev->private = NULL; |
| dev->driver = 0; |
| dev->board_name = NULL; |
| dev->board_ptr = NULL; |
| dev->iobase = 0; |
| dev->irq = 0; |
| dev->read_subdev = NULL; |
| dev->write_subdev = NULL; |
| dev->open = NULL; |
| dev->close = NULL; |
| comedi_set_hw_dev(dev, NULL); |
| } |
| |
| static void __comedi_device_detach(struct comedi_device *dev) |
| { |
| dev->attached = 0; |
| if (dev->driver) { |
| dev->driver->detach(dev); |
| } else { |
| printk("BUG: dev->driver=NULL in comedi_device_detach()\n"); |
| } |
| cleanup_device(dev); |
| } |
| |
| void comedi_device_detach(struct comedi_device *dev) |
| { |
| if (!dev->attached) |
| return; |
| __comedi_device_detach(dev); |
| } |
| |
| int comedi_device_attach(struct comedi_device *dev, struct comedi_devconfig *it) |
| { |
| struct comedi_driver *driv; |
| int ret; |
| |
| if (dev->attached) |
| return -EBUSY; |
| |
| for (driv = comedi_drivers; driv; driv = driv->next) { |
| if (!try_module_get(driv->module)) { |
| printk("comedi: failed to increment module count, skipping\n"); |
| continue; |
| } |
| if (driv->num_names) { |
| dev->board_ptr = comedi_recognize(driv, it->board_name); |
| if (dev->board_ptr == NULL) { |
| module_put(driv->module); |
| continue; |
| } |
| } else { |
| if (strcmp(driv->driver_name, it->board_name)) { |
| module_put(driv->module); |
| continue; |
| } |
| } |
| /* initialize dev->driver here so comedi_error() can be called from attach */ |
| dev->driver = driv; |
| ret = driv->attach(dev, it); |
| if (ret < 0) { |
| module_put(dev->driver->module); |
| __comedi_device_detach(dev); |
| return ret; |
| } |
| goto attached; |
| } |
| |
| /* recognize has failed if we get here */ |
| /* report valid board names before returning error */ |
| for (driv = comedi_drivers; driv; driv = driv->next) { |
| if (!try_module_get(driv->module)) { |
| printk("comedi: failed to increment module count\n"); |
| continue; |
| } |
| comedi_report_boards(driv); |
| module_put(driv->module); |
| } |
| return -EIO; |
| |
| attached: |
| /* do a little post-config cleanup */ |
| ret = postconfig(dev); |
| module_put(dev->driver->module); |
| if (ret < 0) { |
| __comedi_device_detach(dev); |
| return ret; |
| } |
| |
| if (!dev->board_name) { |
| printk("BUG: dev->board_name=<%p>\n", dev->board_name); |
| dev->board_name = "BUG"; |
| } |
| smp_wmb(); |
| dev->attached = 1; |
| |
| return 0; |
| } |
| |
| int comedi_driver_register(struct comedi_driver *driver) |
| { |
| driver->next = comedi_drivers; |
| comedi_drivers = driver; |
| |
| return 0; |
| } |
| |
| int comedi_driver_unregister(struct comedi_driver *driver) |
| { |
| struct comedi_driver *prev; |
| int i; |
| |
| /* check for devices using this driver */ |
| for (i = 0; i < COMEDI_NUM_BOARD_MINORS; i++) { |
| struct comedi_device_file_info *dev_file_info = comedi_get_device_file_info(i); |
| struct comedi_device *dev; |
| |
| if (dev_file_info == NULL) continue; |
| dev = dev_file_info->device; |
| |
| mutex_lock(&dev->mutex); |
| if (dev->attached && dev->driver == driver) { |
| if (dev->use_count) |
| printk("BUG! detaching device with use_count=%d\n", dev->use_count); |
| comedi_device_detach(dev); |
| } |
| mutex_unlock(&dev->mutex); |
| } |
| |
| if (comedi_drivers == driver) { |
| comedi_drivers = driver->next; |
| return 0; |
| } |
| |
| for (prev = comedi_drivers; prev->next; prev = prev->next) { |
| if (prev->next == driver) { |
| prev->next = driver->next; |
| return 0; |
| } |
| } |
| return -EINVAL; |
| } |
| |
| static int postconfig(struct comedi_device *dev) |
| { |
| int i; |
| struct comedi_subdevice *s; |
| struct comedi_async *async = NULL; |
| int ret; |
| |
| for (i = 0; i < dev->n_subdevices; i++) { |
| s = dev->subdevices + i; |
| |
| if (s->type == COMEDI_SUBD_UNUSED) |
| continue; |
| |
| if (s->len_chanlist == 0) |
| s->len_chanlist = 1; |
| |
| if (s->do_cmd) { |
| BUG_ON((s->subdev_flags & (SDF_CMD_READ | |
| SDF_CMD_WRITE)) == 0); |
| BUG_ON(!s->do_cmdtest); |
| |
| async = kzalloc(sizeof(struct comedi_async), GFP_KERNEL); |
| if (async == NULL) { |
| printk("failed to allocate async struct\n"); |
| return -ENOMEM; |
| } |
| init_waitqueue_head(&async->wait_head); |
| async->subdevice = s; |
| s->async = async; |
| |
| #define DEFAULT_BUF_MAXSIZE (64*1024) |
| #define DEFAULT_BUF_SIZE (64*1024) |
| |
| async->max_bufsize = DEFAULT_BUF_MAXSIZE; |
| |
| async->prealloc_buf = NULL; |
| async->prealloc_bufsz = 0; |
| if (comedi_buf_alloc(dev, s, DEFAULT_BUF_SIZE) < 0) { |
| printk("Buffer allocation failed\n"); |
| return -ENOMEM; |
| } |
| if (s->buf_change) { |
| ret = s->buf_change(dev, s, DEFAULT_BUF_SIZE); |
| if (ret < 0) |
| return ret; |
| } |
| comedi_alloc_subdevice_minor(dev, s); |
| } |
| |
| if (!s->range_table && !s->range_table_list) |
| s->range_table = &range_unknown; |
| |
| if (!s->insn_read && s->insn_bits) |
| s->insn_read = insn_rw_emulate_bits; |
| if (!s->insn_write && s->insn_bits) |
| s->insn_write = insn_rw_emulate_bits; |
| |
| if (!s->insn_read) |
| s->insn_read = insn_inval; |
| if (!s->insn_write) |
| s->insn_write = insn_inval; |
| if (!s->insn_bits) |
| s->insn_bits = insn_inval; |
| if (!s->insn_config) |
| s->insn_config = insn_inval; |
| |
| if (!s->poll) |
| s->poll = poll_invalid; |
| } |
| |
| return 0; |
| } |
| |
| /* generic recognize function for drivers that register their supported board names */ |
| void *comedi_recognize(struct comedi_driver * driv, const char *name) |
| { |
| unsigned i; |
| const char *const *name_ptr = driv->board_name; |
| for (i = 0; i < driv->num_names; i++) { |
| if (strcmp(*name_ptr, name) == 0) |
| return (void *)name_ptr; |
| name_ptr = |
| (const char *const *)((const char *)name_ptr + |
| driv->offset); |
| } |
| |
| return NULL; |
| } |
| |
| void comedi_report_boards(struct comedi_driver *driv) |
| { |
| unsigned int i; |
| const char *const *name_ptr; |
| |
| printk("comedi: valid board names for %s driver are:\n", |
| driv->driver_name); |
| |
| name_ptr = driv->board_name; |
| for (i = 0; i < driv->num_names; i++) { |
| printk(" %s\n", *name_ptr); |
| name_ptr = (const char **)((char *)name_ptr + driv->offset); |
| } |
| |
| if (driv->num_names == 0) |
| printk(" %s\n", driv->driver_name); |
| } |
| |
| static int poll_invalid(struct comedi_device *dev, struct comedi_subdevice *s) |
| { |
| return -EINVAL; |
| } |
| |
| int insn_inval(struct comedi_device *dev, struct comedi_subdevice *s, |
| struct comedi_insn *insn, unsigned int *data) |
| { |
| return -EINVAL; |
| } |
| |
| static int insn_rw_emulate_bits(struct comedi_device *dev, struct comedi_subdevice *s, |
| struct comedi_insn *insn, unsigned int *data) |
| { |
| struct comedi_insn new_insn; |
| int ret; |
| static const unsigned channels_per_bitfield = 32; |
| |
| unsigned chan = CR_CHAN(insn->chanspec); |
| const unsigned base_bitfield_channel = |
| (chan < channels_per_bitfield) ? 0 : chan; |
| unsigned int new_data[2]; |
| memset(new_data, 0, sizeof(new_data)); |
| memset(&new_insn, 0, sizeof(new_insn)); |
| new_insn.insn = INSN_BITS; |
| new_insn.chanspec = base_bitfield_channel; |
| new_insn.n = 2; |
| new_insn.data = new_data; |
| new_insn.subdev = insn->subdev; |
| |
| if (insn->insn == INSN_WRITE) { |
| if (!(s->subdev_flags & SDF_WRITABLE)) |
| return -EINVAL; |
| new_data[0] = 1 << (chan - base_bitfield_channel); /* mask */ |
| new_data[1] = data[0] ? (1 << (chan - base_bitfield_channel)) : 0; /* bits */ |
| } |
| |
| ret = s->insn_bits(dev, s, &new_insn, new_data); |
| if (ret < 0) |
| return ret; |
| |
| if (insn->insn == INSN_READ) { |
| data[0] = (new_data[1] >> (chan - base_bitfield_channel)) & 1; |
| } |
| |
| return 1; |
| } |
| |
| static inline unsigned long uvirt_to_kva(pgd_t *pgd, unsigned long adr) |
| { |
| unsigned long ret = 0UL; |
| pmd_t *pmd; |
| pte_t *ptep, pte; |
| pud_t *pud; |
| |
| if (!pgd_none(*pgd)) { |
| pud = pud_offset(pgd, adr); |
| pmd = pmd_offset(pud, adr); |
| if (!pmd_none(*pmd)) { |
| ptep = pte_offset_kernel(pmd, adr); |
| pte = *ptep; |
| if (pte_present(pte)) { |
| ret = (unsigned long) |
| page_address(pte_page(pte)); |
| ret |= (adr & (PAGE_SIZE - 1)); |
| } |
| } |
| } |
| return ret; |
| } |
| |
| static inline unsigned long kvirt_to_kva(unsigned long adr) |
| { |
| unsigned long va, kva; |
| |
| va = adr; |
| kva = uvirt_to_kva(pgd_offset_k(va), va); |
| |
| return kva; |
| } |
| |
| int comedi_buf_alloc(struct comedi_device *dev, struct comedi_subdevice *s, |
| unsigned long new_size) |
| { |
| struct comedi_async *async = s->async; |
| |
| /* Round up new_size to multiple of PAGE_SIZE */ |
| new_size = (new_size + PAGE_SIZE - 1) & PAGE_MASK; |
| |
| /* if no change is required, do nothing */ |
| if (async->prealloc_buf && async->prealloc_bufsz == new_size) { |
| return 0; |
| } |
| /* deallocate old buffer */ |
| if (async->prealloc_buf) { |
| vunmap(async->prealloc_buf); |
| async->prealloc_buf = NULL; |
| async->prealloc_bufsz = 0; |
| } |
| if (async->buf_page_list) { |
| unsigned i; |
| for (i = 0; i < async->n_buf_pages; ++i) { |
| if (async->buf_page_list[i].virt_addr) { |
| mem_map_unreserve(virt_to_page(async-> |
| buf_page_list[i].virt_addr)); |
| if (s->async_dma_dir != DMA_NONE) { |
| dma_free_coherent(dev->hw_dev, |
| PAGE_SIZE, |
| async->buf_page_list[i]. |
| virt_addr, |
| async->buf_page_list[i]. |
| dma_addr); |
| } else { |
| free_page((unsigned long)async-> |
| buf_page_list[i].virt_addr); |
| } |
| } |
| } |
| vfree(async->buf_page_list); |
| async->buf_page_list = NULL; |
| async->n_buf_pages = 0; |
| } |
| /* allocate new buffer */ |
| if (new_size) { |
| unsigned i = 0; |
| unsigned n_pages = new_size >> PAGE_SHIFT; |
| struct page **pages = NULL; |
| |
| async->buf_page_list = |
| vmalloc(sizeof(struct comedi_buf_page) * n_pages); |
| if (async->buf_page_list) { |
| memset(async->buf_page_list, 0, |
| sizeof(struct comedi_buf_page) * n_pages); |
| pages = vmalloc(sizeof(struct page *) * n_pages); |
| } |
| if (pages) { |
| for (i = 0; i < n_pages; i++) { |
| if (s->async_dma_dir != DMA_NONE) { |
| async->buf_page_list[i].virt_addr = |
| dma_alloc_coherent(dev->hw_dev, |
| PAGE_SIZE, |
| &async->buf_page_list[i]. |
| dma_addr, |
| GFP_KERNEL | __GFP_COMP); |
| } else { |
| async->buf_page_list[i].virt_addr = |
| (void *) |
| get_zeroed_page(GFP_KERNEL); |
| } |
| if (async->buf_page_list[i].virt_addr == NULL) { |
| break; |
| } |
| mem_map_reserve(virt_to_page(async-> |
| buf_page_list[i].virt_addr)); |
| pages[i] = |
| virt_to_page(async->buf_page_list[i]. |
| virt_addr); |
| } |
| } |
| if (i == n_pages) { |
| async->prealloc_buf = |
| vmap(pages, n_pages, VM_MAP, |
| PAGE_KERNEL_NOCACHE); |
| } |
| if (pages) { |
| vfree(pages); |
| } |
| if (async->prealloc_buf == NULL) { |
| /* Some allocation failed above. */ |
| if (async->buf_page_list) { |
| for (i = 0; i < n_pages; i++) { |
| if (async->buf_page_list[i].virt_addr == |
| NULL) { |
| break; |
| } |
| mem_map_unreserve(virt_to_page(async-> |
| buf_page_list[i]. |
| virt_addr)); |
| if (s->async_dma_dir != DMA_NONE) { |
| dma_free_coherent(dev->hw_dev, |
| PAGE_SIZE, |
| async->buf_page_list[i]. |
| virt_addr, |
| async->buf_page_list[i]. |
| dma_addr); |
| } else { |
| free_page((unsigned long)async-> |
| buf_page_list[i]. |
| virt_addr); |
| } |
| } |
| vfree(async->buf_page_list); |
| async->buf_page_list = NULL; |
| } |
| return -ENOMEM; |
| } |
| async->n_buf_pages = n_pages; |
| } |
| async->prealloc_bufsz = new_size; |
| |
| return 0; |
| } |
| |
| /* munging is applied to data by core as it passes between user |
| * and kernel space */ |
| unsigned int comedi_buf_munge(struct comedi_async *async, unsigned int num_bytes) |
| { |
| struct comedi_subdevice *s = async->subdevice; |
| unsigned int count = 0; |
| const unsigned num_sample_bytes = bytes_per_sample(s); |
| |
| if (s->munge == NULL || (async->cmd.flags & CMDF_RAWDATA)) { |
| async->munge_count += num_bytes; |
| BUG_ON((int)(async->munge_count - async->buf_write_count) > 0); |
| return num_bytes; |
| } |
| /* don't munge partial samples */ |
| num_bytes -= num_bytes % num_sample_bytes; |
| while (count < num_bytes) { |
| int block_size; |
| |
| block_size = num_bytes - count; |
| if (block_size < 0) { |
| printk("%s: %s: bug! block_size is negative\n", |
| __FILE__, __func__); |
| break; |
| } |
| if ((int)(async->munge_ptr + block_size - |
| async->prealloc_bufsz) > 0) |
| block_size = async->prealloc_bufsz - async->munge_ptr; |
| |
| s->munge(s->device, s, async->prealloc_buf + async->munge_ptr, |
| block_size, async->munge_chan); |
| |
| smp_wmb(); /* barrier insures data is munged in buffer before munge_count is incremented */ |
| |
| async->munge_chan += block_size / num_sample_bytes; |
| async->munge_chan %= async->cmd.chanlist_len; |
| async->munge_count += block_size; |
| async->munge_ptr += block_size; |
| async->munge_ptr %= async->prealloc_bufsz; |
| count += block_size; |
| } |
| BUG_ON((int)(async->munge_count - async->buf_write_count) > 0); |
| return count; |
| } |
| |
| unsigned int comedi_buf_write_n_available(struct comedi_async *async) |
| { |
| unsigned int free_end; |
| unsigned int nbytes; |
| |
| if (async == NULL) |
| return 0; |
| |
| free_end = async->buf_read_count + async->prealloc_bufsz; |
| nbytes = free_end - async->buf_write_alloc_count; |
| nbytes -= nbytes % bytes_per_sample(async->subdevice); |
| /* barrier insures the read of buf_read_count in this |
| query occurs before any following writes to the buffer which |
| might be based on the return value from this query. |
| */ |
| smp_mb(); |
| return nbytes; |
| } |
| |
| /* allocates chunk for the writer from free buffer space */ |
| unsigned int comedi_buf_write_alloc(struct comedi_async *async, unsigned int nbytes) |
| { |
| unsigned int free_end = async->buf_read_count + async->prealloc_bufsz; |
| |
| if ((int)(async->buf_write_alloc_count + nbytes - free_end) > 0) { |
| nbytes = free_end - async->buf_write_alloc_count; |
| } |
| async->buf_write_alloc_count += nbytes; |
| /* barrier insures the read of buf_read_count above occurs before |
| we write data to the write-alloc'ed buffer space */ |
| smp_mb(); |
| return nbytes; |
| } |
| |
| /* allocates nothing unless it can completely fulfill the request */ |
| unsigned int comedi_buf_write_alloc_strict(struct comedi_async *async, |
| unsigned int nbytes) |
| { |
| unsigned int free_end = async->buf_read_count + async->prealloc_bufsz; |
| |
| if ((int)(async->buf_write_alloc_count + nbytes - free_end) > 0) { |
| nbytes = 0; |
| } |
| async->buf_write_alloc_count += nbytes; |
| /* barrier insures the read of buf_read_count above occurs before |
| we write data to the write-alloc'ed buffer space */ |
| smp_mb(); |
| return nbytes; |
| } |
| |
| /* transfers a chunk from writer to filled buffer space */ |
| unsigned comedi_buf_write_free(struct comedi_async *async, unsigned int nbytes) |
| { |
| if ((int)(async->buf_write_count + nbytes - |
| async->buf_write_alloc_count) > 0) { |
| printk("comedi: attempted to write-free more bytes than have been write-allocated.\n"); |
| nbytes = async->buf_write_alloc_count - async->buf_write_count; |
| } |
| async->buf_write_count += nbytes; |
| async->buf_write_ptr += nbytes; |
| comedi_buf_munge(async, async->buf_write_count - async->munge_count); |
| if (async->buf_write_ptr >= async->prealloc_bufsz) { |
| async->buf_write_ptr %= async->prealloc_bufsz; |
| } |
| return nbytes; |
| } |
| |
| /* allocates a chunk for the reader from filled (and munged) buffer space */ |
| unsigned comedi_buf_read_alloc(struct comedi_async *async, unsigned nbytes) |
| { |
| if ((int)(async->buf_read_alloc_count + nbytes - async->munge_count) > |
| 0) { |
| nbytes = async->munge_count - async->buf_read_alloc_count; |
| } |
| async->buf_read_alloc_count += nbytes; |
| /* barrier insures read of munge_count occurs before we actually read |
| data out of buffer */ |
| smp_rmb(); |
| return nbytes; |
| } |
| |
| /* transfers control of a chunk from reader to free buffer space */ |
| unsigned comedi_buf_read_free(struct comedi_async *async, unsigned int nbytes) |
| { |
| /* barrier insures data has been read out of buffer before read count is incremented */ |
| smp_mb(); |
| if ((int)(async->buf_read_count + nbytes - |
| async->buf_read_alloc_count) > 0) { |
| printk("comedi: attempted to read-free more bytes than have been read-allocated.\n"); |
| nbytes = async->buf_read_alloc_count - async->buf_read_count; |
| } |
| async->buf_read_count += nbytes; |
| async->buf_read_ptr += nbytes; |
| async->buf_read_ptr %= async->prealloc_bufsz; |
| return nbytes; |
| } |
| |
| void comedi_buf_memcpy_to(struct comedi_async *async, unsigned int offset, |
| const void *data, unsigned int num_bytes) |
| { |
| unsigned int write_ptr = async->buf_write_ptr + offset; |
| |
| if (write_ptr >= async->prealloc_bufsz) |
| write_ptr %= async->prealloc_bufsz; |
| |
| while (num_bytes) { |
| unsigned int block_size; |
| |
| if (write_ptr + num_bytes > async->prealloc_bufsz) |
| block_size = async->prealloc_bufsz - write_ptr; |
| else |
| block_size = num_bytes; |
| |
| memcpy(async->prealloc_buf + write_ptr, data, block_size); |
| |
| data += block_size; |
| num_bytes -= block_size; |
| |
| write_ptr = 0; |
| } |
| } |
| |
| void comedi_buf_memcpy_from(struct comedi_async *async, unsigned int offset, |
| void *dest, unsigned int nbytes) |
| { |
| void *src; |
| unsigned int read_ptr = async->buf_read_ptr + offset; |
| |
| if (read_ptr >= async->prealloc_bufsz) |
| read_ptr %= async->prealloc_bufsz; |
| |
| while (nbytes) { |
| unsigned int block_size; |
| |
| src = async->prealloc_buf + read_ptr; |
| |
| if (nbytes >= async->prealloc_bufsz - read_ptr) |
| block_size = async->prealloc_bufsz - read_ptr; |
| else |
| block_size = nbytes; |
| |
| memcpy(dest, src, block_size); |
| nbytes -= block_size; |
| dest += block_size; |
| read_ptr = 0; |
| } |
| } |
| |
| unsigned int comedi_buf_read_n_available(struct comedi_async *async) |
| { |
| unsigned num_bytes; |
| |
| if (async == NULL) |
| return 0; |
| num_bytes = async->munge_count - async->buf_read_count; |
| /* barrier insures the read of munge_count in this |
| query occurs before any following reads of the buffer which |
| might be based on the return value from this query. |
| */ |
| smp_rmb(); |
| return num_bytes; |
| } |
| |
| int comedi_buf_get(struct comedi_async *async, short *x) |
| { |
| unsigned int n = comedi_buf_read_n_available(async); |
| |
| if (n < sizeof(short)) |
| return 0; |
| comedi_buf_read_alloc(async, sizeof(short)); |
| *x = *(short *) (async->prealloc_buf + async->buf_read_ptr); |
| comedi_buf_read_free(async, sizeof(short)); |
| return 1; |
| } |
| |
| int comedi_buf_put(struct comedi_async *async, short x) |
| { |
| unsigned int n = comedi_buf_write_alloc_strict(async, sizeof(short)); |
| |
| if (n < sizeof(short)) { |
| async->events |= COMEDI_CB_ERROR; |
| return 0; |
| } |
| *(short *) (async->prealloc_buf + async->buf_write_ptr) = x; |
| comedi_buf_write_free(async, sizeof(short)); |
| return 1; |
| } |
| |
| void comedi_reset_async_buf(struct comedi_async *async) |
| { |
| async->buf_write_alloc_count = 0; |
| async->buf_write_count = 0; |
| async->buf_read_alloc_count = 0; |
| async->buf_read_count = 0; |
| |
| async->buf_write_ptr = 0; |
| async->buf_read_ptr = 0; |
| |
| async->cur_chan = 0; |
| async->scan_progress = 0; |
| async->munge_chan = 0; |
| async->munge_count = 0; |
| async->munge_ptr = 0; |
| |
| async->events = 0; |
| } |
| |
| int comedi_auto_config(struct device *hardware_device, const char *board_name, const int *options, unsigned num_options) |
| { |
| struct comedi_devconfig it; |
| int minor; |
| struct comedi_device_file_info *dev_file_info; |
| int retval; |
| unsigned *private_data = NULL; |
| |
| if (!comedi_autoconfig) { |
| dev_set_drvdata(hardware_device, NULL); |
| return 0; |
| } |
| |
| minor = comedi_alloc_board_minor(hardware_device); |
| if (minor < 0) return minor; |
| |
| private_data = kmalloc(sizeof(unsigned), GFP_KERNEL); |
| if (private_data == NULL) { |
| retval = -ENOMEM; |
| goto cleanup; |
| } |
| *private_data = minor; |
| dev_set_drvdata(hardware_device, private_data); |
| |
| dev_file_info = comedi_get_device_file_info(minor); |
| |
| memset(&it, 0, sizeof(it)); |
| strncpy(it.board_name, board_name, COMEDI_NAMELEN); |
| it.board_name[COMEDI_NAMELEN - 1] = '\0'; |
| BUG_ON(num_options > COMEDI_NDEVCONFOPTS); |
| memcpy(it.options, options, num_options * sizeof(int)); |
| |
| mutex_lock(&dev_file_info->device->mutex); |
| retval = comedi_device_attach(dev_file_info->device, &it); |
| mutex_unlock(&dev_file_info->device->mutex); |
| |
| cleanup: |
| if (retval < 0) |
| { |
| kfree(private_data); |
| comedi_free_board_minor(minor); |
| } |
| return retval; |
| } |
| |
| void comedi_auto_unconfig(struct device *hardware_device) |
| { |
| unsigned *minor = (unsigned *)dev_get_drvdata(hardware_device); |
| if (minor == NULL) return; |
| |
| BUG_ON(*minor >= COMEDI_NUM_BOARD_MINORS); |
| |
| comedi_free_board_minor(*minor); |
| dev_set_drvdata(hardware_device, NULL); |
| kfree(minor); |
| } |
| |
| int comedi_pci_auto_config(struct pci_dev *pcidev, const char *board_name) |
| { |
| int options[2]; |
| |
| /* pci bus */ |
| options[0] = pcidev->bus->number; |
| /* pci slot */ |
| options[1] = PCI_SLOT(pcidev->devfn); |
| |
| return comedi_auto_config(&pcidev->dev, board_name, |
| options, ARRAY_SIZE(options)); |
| } |
| |
| void comedi_pci_auto_unconfig(struct pci_dev *pcidev) |
| { |
| comedi_auto_unconfig(&pcidev->dev); |
| } |
| |
| int comedi_usb_auto_config(struct usb_device *usbdev, |
| const char *board_name) |
| { |
| BUG_ON(usbdev == NULL); |
| return comedi_auto_config(&usbdev->dev, board_name, NULL, 0); |
| } |
| |
| void comedi_usb_auto_unconfig(struct usb_device *usbdev) |
| { |
| BUG_ON(usbdev == NULL); |
| comedi_auto_unconfig(&usbdev->dev); |
| } |