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authorStefan Richter <stefanr@s5r6.in-berlin.de>2010-10-10 00:12:20 +0200
committerStefan Richter <stefanr@s5r6.in-berlin.de>2010-10-11 14:48:03 +0200
commit66fa12c571d35e3cd62574c65f1785a460105397 (patch)
treeb4f8de3d5ca827d2b134ed628628a7bff46967ca /drivers/ieee1394/dv1394.h
parentieee1394: move init_ohci1394_dma to drivers/firewire/ (diff)
downloadlinux-66fa12c571d35e3cd62574c65f1785a460105397.tar.xz
linux-66fa12c571d35e3cd62574c65f1785a460105397.zip
ieee1394: remove the old IEEE 1394 driver stack
The drivers - ohci1394 (controller driver) - ieee1394 (core) - dv1394, raw1394, video1394 (userspace ABI) - eth1394, sbp2 (protocol drivers) are replaced by - firewire-ohci (controller driver) - firewire-core (core and userspace ABI) - firewire-net, firewire-sbp2 (protocol drivers) which are more featureful, better performing, and more secure than the older drivers; all with a smaller and more modern code base. The driver firedtv in drivers/media/dvb/firewire/ contains backends to both ieee1394 and firewire-core. Its ieee1394 backend code can be removed in an independent commit; firedtv as-is builds and works fine without ieee1394. The driver pcilynx (an incomplete controller driver) is deleted without replacement since PCILynx cards are extremely rare. Owners of these cards use them with the stand-alone bus sniffer driver nosy instead. The drivers nosy and init_ohci1394_dma which do not interact with either of the two IEEE 1394 stacks are not affected by the ieee1394 subsystem removal. There are still some issues with the newer firewire subsystem compared to the older one: - The rare and quirky controllers ALi M52xx, Apple UniNorth v1, NVIDIA NForce2 are even less well supported by firewire-ohci than by ohci1394. I am looking into the M52xx issue. - The experimental firewire-net is reportedly less stable than its experimental cousin eth1394. - Audio playback of a certain group of audio devices (ones based on DICE chipset with EAP; supported by prerelease FFADO code) does not work yet. This issue is still under investigation. - There were some ieee1394 based out-of-the-mainline drivers. Of them, only lisight, an audio driver for iSight webcams, seems still useful. Work is underway to reimplement it on top of firewire-core. All these remainig issues are minor; they should not stand in the way of overall better user experience of IEEE 1394 on Linux, together with a reduction in support efforts and maintenance burden. The coexistence of two IEEE 1394 kernel driver stacks in the mainline since 2.6.22 shall end now, as announced earlier this year. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Diffstat (limited to 'drivers/ieee1394/dv1394.h')
-rw-r--r--drivers/ieee1394/dv1394.h305
1 files changed, 0 insertions, 305 deletions
diff --git a/drivers/ieee1394/dv1394.h b/drivers/ieee1394/dv1394.h
deleted file mode 100644
index 5807f5289810..000000000000
--- a/drivers/ieee1394/dv1394.h
+++ /dev/null
@@ -1,305 +0,0 @@
-/*
- * dv1394.h - DV input/output over IEEE 1394 on OHCI chips
- * Copyright (C)2001 Daniel Maas <dmaas@dcine.com>
- * receive by Dan Dennedy <dan@dennedy.org>
- *
- * based on:
- * video1394.h - driver for OHCI 1394 boards
- * Copyright (C)1999,2000 Sebastien Rougeaux <sebastien.rougeaux@anu.edu.au>
- * Peter Schlaile <udbz@rz.uni-karlsruhe.de>
- *
- * 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
- */
-
-#ifndef _DV_1394_H
-#define _DV_1394_H
-
-/* This is the public user-space interface. Try not to break it. */
-
-#define DV1394_API_VERSION 0x20011127
-
-/* ********************
- ** **
- ** DV1394 API **
- ** **
- ********************
-
- There are two methods of operating the DV1394 DV output device.
-
- 1)
-
- The simplest is an interface based on write(): simply write
- full DV frames of data to the device, and they will be transmitted
- as quickly as possible. The FD may be set for non-blocking I/O,
- in which case you can use select() or poll() to wait for output
- buffer space.
-
- To set the DV output parameters (e.g. whether you want NTSC or PAL
- video), use the DV1394_INIT ioctl, passing in the parameters you
- want in a struct dv1394_init.
-
- Example 1:
- To play a raw .DV file: cat foo.DV > /dev/dv1394
- (cat will use write() internally)
-
- Example 2:
- static struct dv1394_init init = {
- 0x63, (broadcast channel)
- 4, (four-frame ringbuffer)
- DV1394_NTSC, (send NTSC video)
- 0, 0 (default empty packet rate)
- }
-
- ioctl(fd, DV1394_INIT, &init);
-
- while (1) {
- read( <a raw DV file>, buf, DV1394_NTSC_FRAME_SIZE );
- write( <the dv1394 FD>, buf, DV1394_NTSC_FRAME_SIZE );
- }
-
- 2)
-
- For more control over buffering, and to avoid unnecessary copies
- of the DV data, you can use the more sophisticated the mmap() interface.
- First, call the DV1394_INIT ioctl to specify your parameters,
- including the number of frames in the ringbuffer. Then, calling mmap()
- on the dv1394 device will give you direct access to the ringbuffer
- from which the DV card reads your frame data.
-
- The ringbuffer is simply one large, contiguous region of memory
- containing two or more frames of packed DV data. Each frame of DV data
- is 120000 bytes (NTSC) or 144000 bytes (PAL).
-
- Fill one or more frames in the ringbuffer, then use the DV1394_SUBMIT_FRAMES
- ioctl to begin I/O. You can use either the DV1394_WAIT_FRAMES ioctl
- or select()/poll() to wait until the frames are transmitted. Next, you'll
- need to call the DV1394_GET_STATUS ioctl to determine which ringbuffer
- frames are clear (ready to be filled with new DV data). Finally, use
- DV1394_SUBMIT_FRAMES again to send the new data to the DV output.
-
-
- Example: here is what a four-frame ringbuffer might look like
- during DV transmission:
-
-
- frame 0 frame 1 frame 2 frame 3
-
- *--------------------------------------*
- | CLEAR | DV data | DV data | CLEAR |
- *--------------------------------------*
- <ACTIVE>
-
- transmission goes in this direction --->>>
-
-
- The DV hardware is currently transmitting the data in frame 1.
- Once frame 1 is finished, it will automatically transmit frame 2.
- (if frame 2 finishes before frame 3 is submitted, the device
- will continue to transmit frame 2, and will increase the dropped_frames
- counter each time it repeats the transmission).
-
-
- If you called DV1394_GET_STATUS at this instant, you would
- receive the following values:
-
- n_frames = 4
- active_frame = 1
- first_clear_frame = 3
- n_clear_frames = 2
-
- At this point, you should write new DV data into frame 3 and optionally
- frame 0. Then call DV1394_SUBMIT_FRAMES to inform the device that
- it may transmit the new frames.
-
- ERROR HANDLING
-
- An error (buffer underflow/overflow or a break in the DV stream due
- to a 1394 bus reset) can be detected by checking the dropped_frames
- field of struct dv1394_status (obtained through the
- DV1394_GET_STATUS ioctl).
-
- The best way to recover from such an error is to re-initialize
- dv1394, either by using the DV1394_INIT ioctl call, or closing the
- file descriptor and opening it again. (note that you must unmap all
- ringbuffer mappings when closing the file descriptor, or else
- dv1394 will still be considered 'in use').
-
- MAIN LOOP
-
- For maximum efficiency and robustness against bus errors, you are
- advised to model the main loop of your application after the
- following pseudo-code example:
-
- (checks of system call return values omitted for brevity; always
- check return values in your code!)
-
- while ( frames left ) {
-
- struct pollfd *pfd = ...;
-
- pfd->fd = dv1394_fd;
- pfd->revents = 0;
- pfd->events = POLLOUT | POLLIN; (OUT for transmit, IN for receive)
-
- (add other sources of I/O here)
-
- poll(pfd, 1, -1); (or select(); add a timeout if you want)
-
- if (pfd->revents) {
- struct dv1394_status status;
-
- ioctl(dv1394_fd, DV1394_GET_STATUS, &status);
-
- if (status.dropped_frames > 0) {
- reset_dv1394();
- } else {
- for (int i = 0; i < status.n_clear_frames; i++) {
- copy_DV_frame();
- }
- }
- }
- }
-
- where copy_DV_frame() reads or writes on the dv1394 file descriptor
- (read/write mode) or copies data to/from the mmap ringbuffer and
- then calls ioctl(DV1394_SUBMIT_FRAMES) to notify dv1394 that new
- frames are availble (mmap mode).
-
- reset_dv1394() is called in the event of a buffer
- underflow/overflow or a halt in the DV stream (e.g. due to a 1394
- bus reset). To guarantee recovery from the error, this function
- should close the dv1394 file descriptor (and munmap() all
- ringbuffer mappings, if you are using them), then re-open the
- dv1394 device (and re-map the ringbuffer).
-
-*/
-
-
-/* maximum number of frames in the ringbuffer */
-#define DV1394_MAX_FRAMES 32
-
-/* number of *full* isochronous packets per DV frame */
-#define DV1394_NTSC_PACKETS_PER_FRAME 250
-#define DV1394_PAL_PACKETS_PER_FRAME 300
-
-/* size of one frame's worth of DV data, in bytes */
-#define DV1394_NTSC_FRAME_SIZE (480 * DV1394_NTSC_PACKETS_PER_FRAME)
-#define DV1394_PAL_FRAME_SIZE (480 * DV1394_PAL_PACKETS_PER_FRAME)
-
-
-/* ioctl() commands */
-#include "ieee1394-ioctl.h"
-
-
-enum pal_or_ntsc {
- DV1394_NTSC = 0,
- DV1394_PAL
-};
-
-
-
-
-/* this is the argument to DV1394_INIT */
-struct dv1394_init {
- /* DV1394_API_VERSION */
- unsigned int api_version;
-
- /* isochronous transmission channel to use */
- unsigned int channel;
-
- /* number of frames in the ringbuffer. Must be at least 2
- and at most DV1394_MAX_FRAMES. */
- unsigned int n_frames;
-
- /* send/receive PAL or NTSC video format */
- enum pal_or_ntsc format;
-
- /* the following are used only for transmission */
-
- /* set these to zero unless you want a
- non-default empty packet rate (see below) */
- unsigned long cip_n;
- unsigned long cip_d;
-
- /* set this to zero unless you want a
- non-default SYT cycle offset (default = 3 cycles) */
- unsigned int syt_offset;
-};
-
-/* NOTE: you may only allocate the DV frame ringbuffer once each time
- you open the dv1394 device. DV1394_INIT will fail if you call it a
- second time with different 'n_frames' or 'format' arguments (which
- would imply a different size for the ringbuffer). If you need a
- different buffer size, simply close and re-open the device, then
- initialize it with your new settings. */
-
-/* Q: What are cip_n and cip_d? */
-
-/*
- A: DV video streams do not utilize 100% of the potential bandwidth offered
- by IEEE 1394 (FireWire). To achieve the correct rate of data transmission,
- DV devices must periodically insert empty packets into the 1394 data stream.
- Typically there is one empty packet per 14-16 data-carrying packets.
-
- Some DV devices will accept a wide range of empty packet rates, while others
- require a precise rate. If the dv1394 driver produces empty packets at
- a rate that your device does not accept, you may see ugly patterns on the
- DV output, or even no output at all.
-
- The default empty packet insertion rate seems to work for many people; if
- your DV output is stable, you can simply ignore this discussion. However,
- we have exposed the empty packet rate as a parameter to support devices that
- do not work with the default rate.
-
- The decision to insert an empty packet is made with a numerator/denominator
- algorithm. Empty packets are produced at an average rate of CIP_N / CIP_D.
- You can alter the empty packet rate by passing non-zero values for cip_n
- and cip_d to the INIT ioctl.
-
- */
-
-
-
-struct dv1394_status {
- /* this embedded init struct returns the current dv1394
- parameters in use */
- struct dv1394_init init;
-
- /* the ringbuffer frame that is currently being
- displayed. (-1 if the device is not transmitting anything) */
- int active_frame;
-
- /* index of the first buffer (ahead of active_frame) that
- is ready to be filled with data */
- unsigned int first_clear_frame;
-
- /* how many buffers, including first_clear_buffer, are
- ready to be filled with data */
- unsigned int n_clear_frames;
-
- /* how many times the DV stream has underflowed, overflowed,
- or otherwise encountered an error, since the previous call
- to DV1394_GET_STATUS */
- unsigned int dropped_frames;
-
- /* N.B. The dropped_frames counter is only a lower bound on the actual
- number of dropped frames, with the special case that if dropped_frames
- is zero, then it is guaranteed that NO frames have been dropped
- since the last call to DV1394_GET_STATUS.
- */
-};
-
-
-#endif /* _DV_1394_H */