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path: root/include/linux/firewire.h
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2011-01-04firewire: use split transaction timeout only for split transactionsClemens Ladisch
Instead of starting the split transaction timeout timer when any request is submitted, start it only when the destination's ACK_PENDING has been received. This prevents us from using a timeout that is too short, and, if the controller's AT queue is emptying very slowly, from cancelling a packet that has not yet been sent. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-29firewire: add isochronous multichannel receptionStefan Richter
This adds the DMA context programming and userspace ABI for multichannel reception, i.e. for listening on multiple channel numbers by means of a single DMA context. The use case is reception of more streams than there are IR DMA units offered by the link layer. This is already implemented by the older ohci1394 + ieee1394 + raw1394 stack. And as discussed recently on linux1394-devel, this feature is occasionally used in practice. The big drawbacks of this mode are that buffer layout and interrupt generation necessarily differ from single-channel reception: Headers and trailers are not stripped from packets, packets are not aligned with buffer chunks, interrupts are per buffer chunk, not per packet. These drawbacks also cause a rather hefty code footprint to support this rarely used OHCI-1394 feature. (367 lines added, among them 94 lines of added userspace ABI documentation.) This implementation enforces that a multichannel reception context may only listen to channels to which no single-channel context on the same link layer is presently listening to. OHCI-1394 would allow to overlay single-channel contexts by the multi-channel context, but this would be a departure from the present first-come-first-served policy of IR context creation. The implementation is heavily based on an earlier one by Jay Fenlason. Thanks Jay. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-23firewire: cdev: add PHY packet receptionStefan Richter
Add an FW_CDEV_IOC_RECEIVE_PHY_PACKETS ioctl() and FW_CDEV_EVENT_PHY_PACKET_RECEIVED poll()/read() event for /dev/fw*. This can be used to get information from remote PHYs by remote access PHY packets. This is also the 2nd half of the functionality (the receive part) to support a userspace implementation of a VersaPHY transaction layer. Safety considerations: - PHY packets are generally broadcasts, hence some kind of elevated privileges should be required of a process to be able to listen in on PHY packets. This implementation assumes that a process that is allowed to open the /dev/fw* of a local node does have this privilege. There was an inconclusive discussion about introducing POSIX capabilities as a means to check for user privileges for these kinds of operations. Other limitations: - PHY packet reception may be switched on by ioctl() but cannot be switched off again. It would be trivial to provide an off switch, but this is not worth the code. The client should simply close() the fd then, or just ignore further events. - For sake of simplicity of API and kernel-side implementation, no filter per packet content is provided. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-23firewire: normalize status values in packet callbacksStefan Richter
core-transaction.c transmit_complete_callback() and close_transaction() expect packet callback status to be an ACK or RCODE, and ACKs get translated to RCODEs for transaction callbacks. An old comment on the packet callback API (been there from the initial submission of the stack) and the dummy_driver implementation of send_request/send_response deviated from this as they also included -ERRNO in the range of status values. Let's narrow status values down to ACK and RCODE to prevent surprises. RCODE_CANCELLED is chosen as the dummy_driver's RCODE as its meaning of "transaction timed out" comes closest to what happens when a transaction coincides with card removal. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-13firewire: core: integrate software-forced bus resets with bus managementStefan Richter
Bus resets which are triggered - by the kernel drivers after updates of the local nodes' config ROM, - by userspace software via ioctl shall be deferred until after >=2 seconds after the last bus reset. If multiple modifications of the local nodes' config ROM happen in a row, only a single bus reset should happen after them. When the local node's link goes from inactive to active or vice versa, and at the two occasions of bus resets mentioned above --- and if the current gap count differs from 63 --- the bus reset should be preceded by a PHY configuration packet that reaffirms the gap count. Otherwise a bus manager would have to reset the bus again right after that. This is necessary to promote bus stability, e.g. leave grace periods for allocations and reallocations of isochronous channels and bandwidth, SBP-2 reconnections etc.; see IEEE 1394 clause 8.2.1. This change implements all of the above by moving bus reset initiation into a delayed work (except for bus resets which are triggered by the bus manager workqueue job and are performed there immediately). It comes with a necessary addition to the card driver methods that allows to get the current gap count from PHY registers. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-08firewire: cdev: fix fw_cdev_event_bus_reset.bm_node_idStefan Richter
Fix an obscure ABI feature that is a bit of a hassle to implement. However, somebody put it into the ABI, so let's fill in a sensible value there. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-20firewire: remove an unused function argumentStefan Richter
void (*fw_address_callback_t)(..., int speed, ...) is the speed that a remote node chose to transmit a request to us. In case of split transactions, firewire-core will transmit the response at that speed. Upper layer drivers on the other hand (firewire-net, -sbp2, firedtv, and userspace drivers) cannot do anything useful with that speed datum, except log it for debug purposes. But data that is merely potentially (not even actually) used for debug purposes does not belong into the API. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-19firewire: normalize STATE_CLEAR/SET CSR access interfaceStefan Richter
Push the maintenance of STATE_CLEAR/SET.abdicate down into the card driver. This way, the read/write_csr_reg driver method works uniformly across all CSR offsets. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-19firewire: replace get_features card driver hookStefan Richter
by feature variables in the fw_card struct. The hook appeared to be an unnecessary abstraction in the card driver interface. Cleaner would be to pass those feature flags as arguments to fw_card_initialize() or fw_card_add(), but the FairnessControl register is in the SCLK domain and may therefore not be accessible while Link Power Status is off, i.e. before the card->driver->enable call from fw_card_add(). Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-10firewire: core: add CSR abdicate supportClemens Ladisch
Implement the abdicate bit, which is required for bus manager capable nodes and tested by the Base 1394 Test Suite. Finally, something to do at a command reset! :-) Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10firewire: core: add CSR MAINT_UTILITY supportClemens Ladisch
Implement the MAIN_UTILITY register, which is utterly optional but useful as a safe target for diagnostic read/write/broadcast transactions. Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10firewire: add CSR PRIORITY_BUDGET supportClemens Ladisch
If supported by the OHCI controller, implement the PRIORITY_BUDGET register, which is required for nodes that can use asynchronous priority arbitration. To allow the core to determine what features the lowlevel device supports, add a new card driver callback. Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10firewire: core: add CSR SPLIT_TIMEOUT supportClemens Ladisch
Implement the SPLIT_TIMEOUT registers. Besides being required by the spec, this is desirable for some IIDC devices and necessary for many audio devices to be able to increase the timeout from userspace. Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-05-19firewire: core: use separate timeout for each transactionClemens Ladisch
Using a single timeout for all transaction that need to be flushed does not work if the submission of new transactions can defer the timeout indefinitely into the future. We need to have timeouts that do not change due to other transactions; the simplest way to do this is with a separate timer for each transaction. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (+ one lockdep annotation)
2010-04-19firewire: core: clean up config ROM related defined constantsStefan Richter
Clemens Ladisch pointed out that - BIB_IMC is not named like the field is called in the standard, - readers of the code may get worried about the magic 0x0c0083c0, - a CSR_NODE_CAPABILITIES key is there in the header but not put to good use. So let's rename BIB_IMC, add a defined constant for Node_Capabilities and a comment which reassures people that somebody thought about it and they don't have to (or if they still do, tell them where they have to look for confirmation), and prune our incomplete and arbitrary set of defined constants of CSR key IDs. And there is a nother magic number, that of Bus_Information_Block.Bus_Name, to be defined and commented. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-12-29firewire: qualify config ROM cache pointers as const pointersStefan Richter
Several config ROM related functions only peek at the ROM cache; mark their arguments as const pointers. Ditto fw_device.config_rom and fw_unit.directory, as the memory behind them is meant to be write-once. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-12-29firewire: core: fw_csr_string addendumStefan Richter
Witespace and comment changes, and a different way to say i + 1 < end. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-12-29firewire: add fw_csr_string() helper functionClemens Ladisch
The core (sysfs attributes), the firedtv driver, and possible future drivers all read strings from some configuration ROM directory. Factor out the generic code from show_text_leaf() into a new helper function, modified slightly to handle arbitrary buffer sizes. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-12-29firewire: fix use of multiple AV/C devices, allow multiple FCP listenersClemens Ladisch
Control of more than one AV/C device at once --- e.g. camcorders, tape decks, audio devices, TV tuners --- failed or worked only unreliably, depending on driver implementation. This affected kernelspace and userspace drivers alike and was caused by firewire-core's inability to accept multiple registrations of FCP listeners. The fix allows multiple address handlers to be registered for the FCP command and response registers. When a request for these registers is received, all handlers are invoked, and the Firewire response is generated by the core and not by any handler. The cdev API does not change, i.e., userspace is still expected to send a response for FCP requests; this response is silently ignored. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (changelog, rebased, whitespace)
2009-10-31firewire: ohci: 0 may be a valid DMA addressStefan Richter
I was told that there are obscure architectures with non-coherent DMA which may DMA-map to bus address 0. We shall not use 0 as a magic number of uninitialized bus address variables. The packet->payload_length > 0 test cannot be used either (except in at_context_queue_packet) because local requests are not DMA-mapped regardless of payload_length. Hence add a state flag to struct fw_packet. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-10-14firewire: core: optimize Topology Map creationStefan Richter
The Topology Map of the local node was created in CPU byte order, then a temporary big endian copy was created to compute the CRC, and when a read request to the Topology Map arrived it had to be converted to big endian byte order again. We now generate it in big endian byte order in the first place. This also rids us of 1000 bytes stack usage in tasklet context. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-10-14firewire: optimize config ROM creationStefan Richter
The config ROM image of the local node was created in CPU byte order, then a temporary big endian copy was created to compute the CRC, and finally the card driver created its own big endian copy. We now generate it in big endian byte order in the first place to avoid one byte order conversion and the temporary on-stack copy of the ROM image (1000 bytes stack usage in process context). Furthermore, two 1000 bytes memset()s are replaced by one 1000 bytes - ROM length sized memset. The trivial fw_memcpy_{from,to}_be32() helpers are now superfluous and removed. The newly added __compute_block_crc() function will be folded into fw_compute_block_crc() in a subsequent change. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-09-12firewire: core: header file cleanupStefan Richter
fw_card_get, fw_card_put, fw_card_release are currently not exported for use outside the firewire-core. Move their definitions/ declarations from the subsystem header file to the core header file. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-06-25firewire: core: do not DMA-map stack addressesStefan Richter
The DMA mapping API cannot map on-stack addresses, as explained in Documentation/DMA-mapping.txt. Convert the two cases of on-stack packet payload buffers in firewire-core (payload of lock requests in the bus manager work and in iso resource management) to slab-allocated memory. There are a number on-stack buffers for quadlet write or quadlet read requests in firewire-core and firewire-sbp2. These are harmless; they are copied to/ from card driver internal DMA buffers since quadlet payloads are inlined with packet headers. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-06-14firewire: net: allow for unordered unit discoveryStefan Richter
Decouple the creation and destruction of the net_device from the order of discovery and removal of nodes with RFC 2734 unit directories since there is no reliable order. The net_device is now created when the first RFC 2734 unit on a card is discovered, and destroyed when the last RFC 2734 unit on a card went away. This includes all remote units as well as the local unit, which is therefore tracked as a peer now too. Also, locking around the list of peers is slightly extended to guard against peer removal. As a side effect, fwnet_peer.pdg_lock has become superfluous and is deleted. Peer data (max_rec, speed, node ID, generation) are updated more carefully. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-06-14firewire: net: style changesStefan Richter
Change names of types, variables, functions. Omit debug code. Use get_unaligned*, put_unaligned*. Annotate big endian data. Handle errors in __init. Change whitespace. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-06-14firewire: add IPv4 supportJay Fenlason
Implement IPv4 over IEEE 1394 as per RFC 2734 for the newer firewire stack. This feature has only been present in the older ieee1394 stack via the eth1394 driver. Still to do: - fix ipv4_priv and ipv4_node lifetime logic - fix determination of speeds and max payloads - fix bus reset handling - fix unaligned memory accesses - fix coding style - further testing/ improvement of fragment reassembly - perhaps multicast support Signed-off-by: Jay Fenlason <fenlason@redhat.com> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (rebased, copyright note, changelog)
2009-06-14firewire: core: use more outbound tlabelsStefan Richter
Tlabel is a 6 bits wide datum. Wrap it after 63 rather than 31 for more safety against transaction label exhaustion and potential responders' transaction layer bugs. (As noted by Guus Sliepen, this change requires an expansion of tlabel_mask to 64 bits.) Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-06-14firewire: core: don't update Broadcast_Channel if RFC 2734 conditions aren't metStefan Richter
This extra check will avoid Broadcast_Channel register related traffic to many IIDC, SBP-2, and AV/C devices which aren't IRMC or have a max_rec < 8 (i.e. support < 512 bytes async payload). This avoids a little bit of traffic after bus reset and is even more careful with devices which don't implement this CSR. The assumption is that no other protocol than IP over 1394 uses the broadcast channel for streams. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-06-06firewire: add parent-of-unit accessorStefan Richter
Retrieval of an fw_unit's parent is a common pattern in high-level code. Wrap it up as device = fw_parent_device(unit). Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-06-05firewire: reorganize header filesStefan Richter
The three header files of firewire-core, i.e. "drivers/firewire/fw-device.h", "drivers/firewire/fw-topology.h", "drivers/firewire/fw-transaction.h", are replaced by "drivers/firewire/core.h", "include/linux/firewire.h". The latter includes everything which a firewire high-level driver (like firewire-sbp2) needs besides linux/firewire-constants.h, while core.h contains the rest which is needed by firewire-core itself and by low- level drivers (card drivers) like firewire-ohci. High-level drivers can now also reside outside of drivers/firewire without having to add drivers/firewire to the header file search path in makefiles. At least the firedtv driver will be such a driver. I also considered to spread the contents of core.h over several files, one for each .c file where the respective implementation resides. But it turned out that most core .c files will end up including most of the core .h files. Also, the combined core.h isn't unreasonably big, and it will lose more of its contents to linux/firewire.h anyway soon when more firewire drivers are added. (IP-over-1394, firedtv, and there are plans for one or two more.) Furthermore, fw-ohci.h is renamed to ohci.h. The name of core.h and ohci.h is chosen with regard to name changes of the .c files in a follow-up change. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>