From dcadfd7f7c74ef9ee415e072a19bdf6c085159eb Mon Sep 17 00:00:00 2001 From: Takashi Sakamoto Date: Tue, 30 May 2023 08:12:40 +0900 Subject: firewire: core: use union for callback of transaction completion In 1394 OHCI, the OUTPUT_LAST descriptor of Asynchronous Transmit (AT) request context has timeStamp field, in which 1394 OHCI controller record the isochronous cycle when the packet was sent for the request subaction. Additionally, for the case of split transaction in IEEE 1394, Asynchronous Receive (AT) request context is used for response subaction to finish the transaction. The trailer quadlet of descriptor in the context has timeStamp field, in which 1394 OHCI controller records the isochronous cycle when the packet arrived. Current implementation of 1394 OHCI controller driver stores values of both fields to internal structure as time stamp, while Linux FireWire subsystem provides no way to access to it. When using asynchronous transaction service provided by the subsystem, callback function is passed to kernel API. The prototype of callback function has the lack of argument for the values. This commit adds a new callback function for the purpose. It has an additional argument to point to the constant array with two elements. For backward compatibility to kernel space, a new union is also adds to wrap two different prototype of callback function. The fw_transaction structure has the union as a member and a boolean flag to express which function callback is available. The core function is changed to handle the two cases; with or without time stamp. For the error path to process transaction, the isochronous cycle is computed by current value of CYCLE_TIMER register in 1394 OHCI controller. Especially for the case of timeout of split transaction, the expected isochronous cycle is computed. Link: https://lore.kernel.org/r/20230529113406.986289-6-o-takashi@sakamocchi.jp Signed-off-by: Takashi Sakamoto --- include/linux/firewire.h | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) (limited to 'include/linux') diff --git a/include/linux/firewire.h b/include/linux/firewire.h index 1716c01c4e54..d61693341da1 100644 --- a/include/linux/firewire.h +++ b/include/linux/firewire.h @@ -261,6 +261,15 @@ typedef void (*fw_packet_callback_t)(struct fw_packet *packet, typedef void (*fw_transaction_callback_t)(struct fw_card *card, int rcode, void *data, size_t length, void *callback_data); +typedef void (*fw_transaction_callback_with_tstamp_t)(struct fw_card *card, int rcode, + u32 request_tstamp, u32 response_tstamp, void *data, + size_t length, void *callback_data); + +union fw_transaction_callback { + fw_transaction_callback_t without_tstamp; + fw_transaction_callback_with_tstamp_t with_tstamp; +}; + /* * This callback handles an inbound request subaction. It is called in * RCU read-side context, therefore must not sleep. @@ -312,6 +321,7 @@ struct fw_transaction { struct fw_card *card; bool is_split_transaction; struct timer_list split_timeout_timer; + u32 split_timeout_cycle; struct fw_packet packet; @@ -319,7 +329,8 @@ struct fw_transaction { * The data passed to the callback is valid only during the * callback. */ - fw_transaction_callback_t callback; + union fw_transaction_callback callback; + bool with_tstamp; void *callback_data; }; -- cgit v1.2.3 From 39ce342c3a4b763d774c531323d6573af389f332 Mon Sep 17 00:00:00 2001 From: Takashi Sakamoto Date: Tue, 30 May 2023 08:12:40 +0900 Subject: firewire: core: implement variations to send request and wait for response with time stamp In the previous commit, the core function of Linux FireWire subsystem was changed for two cases to operate asynchronous transaction with or without time stamp. This commit changes kernel API for the two cases. Current kernel API, fw_send_request(), is changed to be static inline function to call __fw_send_request(), which receives two argument for union and flag of callback function. The new kernel API, fw_send_request_with_tstamp() is also added as static inline function, too. When calling, the two arguments are copied to internal structure, then used in softIRQ context. Link: https://lore.kernel.org/r/20230529113406.986289-7-o-takashi@sakamocchi.jp Signed-off-by: Takashi Sakamoto --- include/linux/firewire.h | 69 +++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 65 insertions(+), 4 deletions(-) (limited to 'include/linux') diff --git a/include/linux/firewire.h b/include/linux/firewire.h index d61693341da1..a7fd23d0010d 100644 --- a/include/linux/firewire.h +++ b/include/linux/firewire.h @@ -356,10 +356,71 @@ void fw_send_response(struct fw_card *card, struct fw_request *request, int rcode); int fw_get_request_speed(struct fw_request *request); u32 fw_request_get_timestamp(const struct fw_request *request); -void fw_send_request(struct fw_card *card, struct fw_transaction *t, - int tcode, int destination_id, int generation, int speed, - unsigned long long offset, void *payload, size_t length, - fw_transaction_callback_t callback, void *callback_data); + +void __fw_send_request(struct fw_card *card, struct fw_transaction *t, int tcode, + int destination_id, int generation, int speed, unsigned long long offset, + void *payload, size_t length, union fw_transaction_callback callback, + bool with_tstamp, void *callback_data); + +/** + * fw_send_request() - submit a request packet for transmission to generate callback for response + * subaction without time stamp. + * @card: interface to send the request at + * @t: transaction instance to which the request belongs + * @tcode: transaction code + * @destination_id: destination node ID, consisting of bus_ID and phy_ID + * @generation: bus generation in which request and response are valid + * @speed: transmission speed + * @offset: 48bit wide offset into destination's address space + * @payload: data payload for the request subaction + * @length: length of the payload, in bytes + * @callback: function to be called when the transaction is completed + * @callback_data: data to be passed to the transaction completion callback + * + * A variation of __fw_send_request() to generate callback for response subaction without time + * stamp. + */ +static inline void fw_send_request(struct fw_card *card, struct fw_transaction *t, int tcode, + int destination_id, int generation, int speed, + unsigned long long offset, void *payload, size_t length, + fw_transaction_callback_t callback, void *callback_data) +{ + union fw_transaction_callback cb = { + .without_tstamp = callback, + }; + __fw_send_request(card, t, tcode, destination_id, generation, speed, offset, payload, + length, cb, false, callback_data); +} + +/** + * fw_send_request_with_tstamp() - submit a request packet for transmission to generate callback for + * response with time stamp. + * @card: interface to send the request at + * @t: transaction instance to which the request belongs + * @tcode: transaction code + * @destination_id: destination node ID, consisting of bus_ID and phy_ID + * @generation: bus generation in which request and response are valid + * @speed: transmission speed + * @offset: 48bit wide offset into destination's address space + * @payload: data payload for the request subaction + * @length: length of the payload, in bytes + * @callback: function to be called when the transaction is completed + * @callback_data: data to be passed to the transaction completion callback + * + * A variation of __fw_send_request() to generate callback for response subaction with time stamp. + */ +static inline void fw_send_request_with_tstamp(struct fw_card *card, struct fw_transaction *t, + int tcode, int destination_id, int generation, int speed, unsigned long long offset, + void *payload, size_t length, fw_transaction_callback_with_tstamp_t callback, + void *callback_data) +{ + union fw_transaction_callback cb = { + .with_tstamp = callback, + }; + __fw_send_request(card, t, tcode, destination_id, generation, speed, offset, payload, + length, cb, true, callback_data); +} + int fw_cancel_transaction(struct fw_card *card, struct fw_transaction *transaction); int fw_run_transaction(struct fw_card *card, int tcode, int destination_id, -- cgit v1.2.3