From: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com
When a peripheral reports as ATTACHED, the manager may need to follow a programming sequence, e.g. to assign DMA resources and/or assign a command queue for that peripheral.
This patch adds an optional callback, which will be invoked every time the peripheral attaches. This might be overkill in some scenarios, and one could argue that this should be invoked only on the first attachment. The bus does not however track this first attachment with any existing state-mirroring variable, and using dev_num_sticky would not work across suspend-resume cycles.
Signed-off-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com Reviewed-by: Rander Wang rander.wang@intel.com Reviewed-by: Péter Ujfalusi peter.ujfalusi@linux.intel.com Reviewed-by: Ranjani Sridharan ranjani.sridharan@linux.intel.com Signed-off-by: Bard Liao yung-chuan.liao@linux.intel.com --- drivers/soundwire/bus.c | 3 +++ include/linux/soundwire/sdw.h | 3 ++- 2 files changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c index 338f4f0b5d0c..b44f8d0affa6 100644 --- a/drivers/soundwire/bus.c +++ b/drivers/soundwire/bus.c @@ -769,6 +769,9 @@ static int sdw_assign_device_num(struct sdw_slave *slave) /* After xfer of msg, restore dev_num */ slave->dev_num = slave->dev_num_sticky;
+ if (bus->ops && bus->ops->new_peripheral_assigned) + bus->ops->new_peripheral_assigned(bus, dev_num); + return 0; }
diff --git a/include/linux/soundwire/sdw.h b/include/linux/soundwire/sdw.h index ef645de13ae9..c076a3f879b3 100644 --- a/include/linux/soundwire/sdw.h +++ b/include/linux/soundwire/sdw.h @@ -846,6 +846,7 @@ struct sdw_defer { * @post_bank_switch: Callback for post bank switch * @read_ping_status: Read status from PING frames, reported with two bits per Device. * Bits 31:24 are reserved. + * @new_peripheral_assigned: Callback to handle enumeration of new peripheral. */ struct sdw_master_ops { int (*read_prop)(struct sdw_bus *bus); @@ -860,7 +861,7 @@ struct sdw_master_ops { int (*pre_bank_switch)(struct sdw_bus *bus); int (*post_bank_switch)(struct sdw_bus *bus); u32 (*read_ping_status)(struct sdw_bus *bus); - + void (*new_peripheral_assigned)(struct sdw_bus *bus, int dev_num); };
/**