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author | Linus Torvalds <torvalds@linux-foundation.org> | 2011-03-18 10:46:37 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-03-18 10:46:37 -0700 |
commit | d3e458d78167102cc961237cfceef6fffc80c0b3 (patch) | |
tree | e9195c1294daf053614e63ac52b0b44a28479017 /sound/firewire/packets-buffer.c | |
parent | f2e1fbb5f2177227f71c4fc0491e531dd7acd385 (diff) | |
parent | d351cf4603edb2a5bfa9a48d06c425511c63f2a3 (diff) |
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6: (308 commits)
ALSA: sound/pci/asihpi: check adapter index in hpi_ioctl
ALSA: aloop - Fix possible IRQ lock inversion
ALSA: sound/core: merge list_del()/list_add_tail() to list_move_tail()
ALSA: ctxfi - use list_move() instead of list_del()/list_add() combination
ALSA: firewire - msleep needs delay.h
ALSA: firewire-lib, firewire-speakers: handle packet queueing errors
ALSA: firewire-lib: allocate DMA buffer separately
ALSA: firewire-lib: use no-info SYT for packets without SYT sample
ALSA: add LaCie FireWire Speakers/Griffin FireWave Surround driver
ALSA: hda - Remove an unused variable in patch_realtek.c
ALSA: hda - pin-adc-mux-dmic auto-configuration of 92HD8X codecs
ALSA: hda - fix digital mic selection in mixer on 92HD8X codecs
ALSA: hda - Move default input-src selection to init part
ALSA: hda - Initialize special cases for input src in init phase
ALSA: ctxfi - Clear input settings before initialization
ALSA: ctxfi - Fix SPDIF status retrieval
ALSA: ctxfi - Fix incorrect SPDIF status bit mask
ALSA: ctxfi - Fix microphone boost codes/comments
ALSA: atiixp - Fix wrong time-out checks during ac-link reset
ALSA: intel8x0m: append 'm' to "r_intel8x0"
...
Diffstat (limited to 'sound/firewire/packets-buffer.c')
-rw-r--r-- | sound/firewire/packets-buffer.c | 74 |
1 files changed, 74 insertions, 0 deletions
diff --git a/sound/firewire/packets-buffer.c b/sound/firewire/packets-buffer.c new file mode 100644 index 00000000000..1e20e60ba6a --- /dev/null +++ b/sound/firewire/packets-buffer.c @@ -0,0 +1,74 @@ +/* + * helpers for managing a buffer for many packets + * + * Copyright (c) Clemens Ladisch <clemens@ladisch.de> + * Licensed under the terms of the GNU General Public License, version 2. + */ + +#include <linux/firewire.h> +#include <linux/slab.h> +#include "packets-buffer.h" + +/** + * iso_packets_buffer_init - allocates the memory for packets + * @b: the buffer structure to initialize + * @unit: the device at the other end of the stream + * @count: the number of packets + * @packet_size: the (maximum) size of a packet, in bytes + * @direction: %DMA_TO_DEVICE or %DMA_FROM_DEVICE + */ +int iso_packets_buffer_init(struct iso_packets_buffer *b, struct fw_unit *unit, + unsigned int count, unsigned int packet_size, + enum dma_data_direction direction) +{ + unsigned int packets_per_page, pages; + unsigned int i, page_index, offset_in_page; + void *p; + int err; + + b->packets = kmalloc(count * sizeof(*b->packets), GFP_KERNEL); + if (!b->packets) { + err = -ENOMEM; + goto error; + } + + packet_size = L1_CACHE_ALIGN(packet_size); + packets_per_page = PAGE_SIZE / packet_size; + if (WARN_ON(!packets_per_page)) { + err = -EINVAL; + goto error; + } + pages = DIV_ROUND_UP(count, packets_per_page); + + err = fw_iso_buffer_init(&b->iso_buffer, fw_parent_device(unit)->card, + pages, direction); + if (err < 0) + goto err_packets; + + for (i = 0; i < count; ++i) { + page_index = i / packets_per_page; + p = page_address(b->iso_buffer.pages[page_index]); + offset_in_page = (i % packets_per_page) * packet_size; + b->packets[i].buffer = p + offset_in_page; + b->packets[i].offset = page_index * PAGE_SIZE + offset_in_page; + } + + return 0; + +err_packets: + kfree(b->packets); +error: + return err; +} + +/** + * iso_packets_buffer_destroy - frees packet buffer resources + * @b: the buffer structure to free + * @unit: the device at the other end of the stream + */ +void iso_packets_buffer_destroy(struct iso_packets_buffer *b, + struct fw_unit *unit) +{ + fw_iso_buffer_destroy(&b->iso_buffer, fw_parent_device(unit)->card); + kfree(b->packets); +} |