Commit 6bac0d8d authored by Pierre-Louis Bossart's avatar Pierre-Louis Bossart Committed by Vinod Koul
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soundwire: bus: add new manager callback to deal with peripheral enumeration 



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: default avatarPierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: default avatarRander Wang <rander.wang@intel.com>
Reviewed-by: default avatarPéter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: default avatarRanjani Sridharan <ranjani.sridharan@linux.intel.com>
Signed-off-by: default avatarBard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20230515071042.2038-20-yung-chuan.liao@linux.intel.com


Signed-off-by: default avatarVinod Koul <vkoul@kernel.org>
parent 7ba18639

drivers/soundwire/bus.c

+3 −0
Original line number Diff line number Diff line
@@ -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;

}

include/linux/soundwire/sdw.h

+2 −1
Original line number Diff line number Diff line
@@ -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);

};



/**