kernel/linux.git/drivers/firewire/core.h, branch v6.12.80

Revert "firewire: core: move workqueue handler from 1394 OHCI driver to core function"

2024-09-12T13:30:35+00:00

This reverts commit 767bfb9ef27ebf760290d9f8bc303828b018c312. It appears that the call of ohci_flush_iso_completions() in the work item scheduled by hardIRQ of 1394 OHCI for any isochronous context changes the timing to queue events in the view of user space application. Link: https://lore.kernel.org/r/20240912133038.238786-3-o-takashi@sakamocchi.jp Signed-off-by: Takashi Sakamoto

firewire: core: move workqueue handler from 1394 OHCI driver to core function

2024-09-09T14:00:17+00:00

In current implementation, the work item for isochronous context executes the same procedure of fw_iso_context_flush_completions() internally. There is a space to refactor the implementation. This commit calls fw_iso_context_flush_completions() in the work item. It obsoletes fw_iso_context_init_work(). It also obsoletes a pair of disable_work_sync() and enable_work() since the usage of test_and_set_bit_lock() mediates concurrent call already. Link: https://lore.kernel.org/r/20240909140018.65289-2-o-takashi@sakamocchi.jp Signed-off-by: Takashi Sakamoto

firewire: core: expose kernel API to schedule work item to process isochronous context

2024-09-08T04:05:48+00:00

In packet-per-buffer mode for isochronous context of 1394 OHCI, software can schedule hardIRQ to the buffer in which the content of isochronous packet is processed. The actual behaviour is different between isochronous receive (IR) and transmit (IT) contexts in respect to isochronous cycle in which the hardIRQ occurs. In IR context, the hardIRQ occurs when the buffer is filled actually by the content of received packet. If there are any isochronous cycles in which the packet transmission is skipped, it is postponed to generate the hardIRQ in respect to the isochronous cycle. In IT context, software can schedule the content of packet every isochronous cycle including skipping, therefore the hardIRQ occurs in the isochronous cycle to which the software scheduled. ALSA firewire stack uses the packet-per-buffer mode for both IR/IT contexts. To process time stamp per packet (or per sample in some cases) steadily for media clock recovery against unexpected transmission skips, it uses an IT context to operate all of isochronous contexts by calls of fw_iso_context_flush_completions() in the bottom-half of hardIRQ for the IT context. Although it looks well to handle all of isochronous contexts in a single bottom-half context, it relatively takes longer time. In the future code integration (not yet), it is possible to apply parallelism method to process these context. In the case, it is useful to allow unit drivers to schedule work items to process these isochronous contexts. As a preparation, this commit exposes fw_iso_context_schedule_flush_completions() as a kernel API available by unit drivers. It is renamed from fw_iso_context_queue_work() since it is a counter part of fw_iso_context_flush_completions(). Link: https://lore.kernel.org/r/20240908040549.75304-2-o-takashi@sakamocchi.jp Signed-off-by: Takashi Sakamoto

firewire: core: add local API to queue work item to workqueue specific to isochronous contexts

2024-09-04T12:51:51+00:00

In the previous commit, the workqueue is added per the instance of fw_card structure for isochronous contexts. The workqueue is designed to be used by the implementation of fw_card_driver structure underlying the fw_card. This commit adds some local APIs to be used by the implementation. Tested-by: Edmund Raile Link: https://lore.kernel.org/r/20240904125155.461886-3-o-takashi@sakamocchi.jp Signed-off-by: Takashi Sakamoto

firewire: core: allocate workqueue to handle isochronous contexts in card

2024-09-04T12:51:50+00:00

This commit adds a workqueue dedicated for isochronous context processing. The workqueue is allocated per instance of fw_card structure to satisfy the following characteristics descending from 1394 OHCI specification: In 1394 OHCI specification, memory pages are reserved to each isochronous context dedicated to DMA transmission. It allows to operate these per-context pages concurrently. Software can schedule hardware interrupt for several isochronous context to the same cycle, thus WQ_UNBOUND is specified. Additionally, it is sleepable to operate the content of pages, thus WQ_BH is not used. The isochronous context delivers the packets with time stamp, thus WQ_HIGHPRI is specified for semi real-time data such as IEC 61883-1/6 protocol implemented by ALSA firewire stack. The isochronous context is not used by the implementation of SCSI over IEEE1394 protocol (sbp2), thus WQ_MEM_RECLAIM is not specified. It is useful for users to adjust cpu affinity of the workqueue depending on their work loads, thus WQ_SYS is specified to expose the attributes to user space. Tested-by: Edmund Raile Link: https://lore.kernel.org/r/20240904125155.461886-2-o-takashi@sakamocchi.jp Signed-off-by: Takashi Sakamoto

firewire: core: use xarray instead of idr to maintain client resource

2024-08-12T23:52:10+00:00

In core function, the instances of some client resource structures are maintained by IDR. As of kernel v6.0, IDR has been superseded by XArray and deprecated. This commit replaces the usage of IDR with XArray to maintain the resource instances. The instance of XArray is allocated per client with XA_FLAGS_ALLOC1 so that the index of allocated entry is greater than zero and returns to user space client as handle of the resource. Link: https://lore.kernel.org/r/20240812235210.28458-6-o-takashi@sakamocchi.jp Signed-off-by: Takashi Sakamoto

firewire: core: replace IDR with XArray to maintain fw_device

2024-08-12T01:42:50+00:00

In core function, the instances of fw_device corresponding to firewire device node in system are maintained by IDR. As of kernel v6.0, IDR has been superseded by XArray and deprecated. This commit replaces the usage of IDR with XArray to maintain the device instances. The instance of XArray is allocated statically, and initialized with XA_FLAGS_ALLOC so that the index of allocated entry starts with zero and available as the minor identifier of device node. Link: https://lore.kernel.org/r/20240812014251.165492-2-o-takashi@sakamocchi.jp Signed-off-by: Takashi Sakamoto

firewire: core: utilize kref to maintain fw_node with reference counting

2024-08-01T02:26:29+00:00

Current implementation directly uses refcount_t to maintain the life time of fw_node, while kref is available for the same purpose. This commit replaces the implementation with kref. Link: https://lore.kernel.org/r/20240801022629.31857-1-o-takashi@sakamocchi.jp Signed-off-by: Takashi Sakamoto

Revert "firewire: core: option to log bus reset initiation"

2024-05-06T02:06:06+00:00

This reverts commit 6732491243045f5a7e1995b4be5f3c964b579ebd. The former commit adds some alternative tracepoints events to replace the reverted kernel log messages. Link: https://lore.kernel.org/r/20240501073238.72769-5-o-takashi@sakamocchi.jp Signed-off-by: Takashi Sakamoto

firewire: core: obsolete tcode check macros with inline functions

2024-05-06T02:06:05+00:00

This commit declares the helper functions to check tcode to obsolete the functional macros. Link: https://lore.kernel.org/r/20240428071347.409202-7-o-takashi@sakamocchi.jp Signed-off-by: Takashi Sakamoto