From 5a43dc9f4ee0a3624d0598ee14e8ef8468914525 Mon Sep 17 00:00:00 2001 From: Takashi Sakamoto Date: Mon, 13 Oct 2025 23:03:10 +0900 Subject: firewire: core: detect device quirk when reading configuration ROM Every time the bus manager runs, the cached configuration ROM content of the IRM device is investigated to detect device-specific quirks. This detection can be performed in advance when reading the configuration ROM. This commit adds device quirk flags to the fw_device structure, and initializes them after reading the bus information block of the configuration ROM. The quirk flags are immutable once the configuration ROM has been read. Although they are likely accessed concurrently only by the bus manager, this commit ensures safe access by preventing torn writes and reads using the WRITE_ONCE()/READ_ONCE() macros. Link: https://lore.kernel.org/r/20251013140311.97159-2-o-takashi@sakamocchi.jp Signed-off-by: Takashi Sakamoto --- include/linux/firewire.h | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'include/linux') diff --git a/include/linux/firewire.h b/include/linux/firewire.h index 6d208769d456..161829cfcc00 100644 --- a/include/linux/firewire.h +++ b/include/linux/firewire.h @@ -170,6 +170,14 @@ struct fw_attribute_group { struct attribute *attrs[13]; }; +enum fw_device_quirk { + // See afa1282a35d3 ("firewire: core: check for 1394a compliant IRM, fix inaccessibility of Sony camcorder"). + FW_DEVICE_QUIRK_IRM_IS_1394_1995_ONLY = BIT(0), + + // See a509e43ff338 ("firewire: core: fix unstable I/O with Canon camcorder"). + FW_DEVICE_QUIRK_IRM_IGNORES_BUS_MANAGER = BIT(1), +}; + enum fw_device_state { FW_DEVICE_INITIALIZING, FW_DEVICE_RUNNING, @@ -203,6 +211,9 @@ struct fw_device { struct fw_card *card; struct device device; + // A set of enum fw_device_quirk. + int quirks; + struct mutex client_list_mutex; struct list_head client_list; -- cgit v1.2.3