Re: [PATCH 2/4] soundwire: introduce SDW_DEV_NUM_ALLOC_IDA_WAKE_ONLY

On 31-05-23, 11:37, Bard Liao wrote:

From: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com

This patch adds a new Device Number allocation strategy, with the IDA used only for devices that are wake-capable.

"regular" devices such as amplifiers will use Device Numbers [1..min_ida-1].

"wake-capable" devices such as jack or microphone codecs will use Device Numbers [min_ida..11].

This hybrid strategy extends the number of supported devices in a system by only constraining the allocation if required, e.g. in the case of Intel LunarLake platforms the wake-capable devices are required to have a unique address to use the HDaudio SDI and HDAudio WAKEEN/WAKESTS registers.

This seems to be a consequence of Intel hardware decisions, so I guess best suited place for this is Intel controller, do we really want to have this in core logic?

Signed-off-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com Reviewed-by: Rander Wang rander.wang@intel.com Signed-off-by: Bard Liao yung-chuan.liao@linux.intel.com

---

drivers/soundwire/bus.c | 26 +++++++++++++++++++++----- include/linux/soundwire/sdw.h | 4 ++++ 2 files changed, 25 insertions(+), 5 deletions(-)

diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c index e8c1c55a2a73..6f465cce8369 100644 --- a/drivers/soundwire/bus.c +++ b/drivers/soundwire/bus.c @@ -159,7 +159,9 @@ static int sdw_delete_slave(struct device *dev, void *data)

if (slave->dev_num) { /* clear dev_num if assigned */ clear_bit(slave->dev_num, bus->assigned);

• if (bus->dev_num_alloc == SDW_DEV_NUM_ALLOC_IDA)
  

• if (bus->dev_num_alloc == SDW_DEV_NUM_ALLOC_IDA ||
  

•     (bus->dev_num_alloc == SDW_DEV_NUM_ALLOC_IDA_WAKE_ONLY &&
  

•      slave->prop.wake_capable))
  ida_free(&sdw_peripheral_ida, slave->dev_num);
  

  } list_del_init(&slave->node);

@@ -699,17 +701,31 @@ EXPORT_SYMBOL(sdw_compare_devid); /* called with bus_lock held */ static int sdw_get_device_num(struct sdw_slave *slave) {

• struct sdw_bus *bus = slave->bus; int bit;

• if (slave->bus->dev_num_alloc == SDW_DEV_NUM_ALLOC_IDA) {

• if (bus->dev_num_alloc == SDW_DEV_NUM_ALLOC_IDA ||

•    (bus->dev_num_alloc == SDW_DEV_NUM_ALLOC_IDA_WAKE_ONLY &&
  

•     slave->prop.wake_capable)) {
  

  bit = ida_alloc_range(&sdw_peripheral_ida,

• 		      slave->bus->dev_num_ida_min, SDW_MAX_DEVICES,
  

• 		      bus->dev_num_ida_min, SDW_MAX_DEVICES,
  	      GFP_KERNEL);
  

  if (bit < 0) goto err; } else {

• bit = find_first_zero_bit(slave->bus->assigned, SDW_MAX_DEVICES);
  

• if (bit == SDW_MAX_DEVICES) {
  

• int max_devices = SDW_MAX_DEVICES;
  

• if (bus->dev_num_alloc == SDW_DEV_NUM_ALLOC_IDA_WAKE_ONLY &&
  

•     !slave->prop.wake_capable) {
  

• 	max_devices = bus->dev_num_ida_min - 1;
  

• 	/* range check */
  

• 	if (max_devices < 1 || max_devices > SDW_MAX_DEVICES)
  

• 		return -EINVAL;
  

• }
  

• bit = find_first_zero_bit(bus->assigned, max_devices);
  

• if (bit == max_devices) {
  bit = -ENODEV;
  goto err;
  

  }

diff --git a/include/linux/soundwire/sdw.h b/include/linux/soundwire/sdw.h index 4656d6d0f3bb..8a7541ac735e 100644 --- a/include/linux/soundwire/sdw.h +++ b/include/linux/soundwire/sdw.h @@ -869,10 +869,14 @@ struct sdw_master_ops {

• @SDW_DEV_NUM_ALLOC_DEFAULT: unconstrained first-come-first-serve allocation,
• using range [1, 11]
• @SDW_DEV_NUM_ALLOC_IDA: IDA-based allocation, using range [ida_min, 11]

• • @SDW_DEV_NUM_ALLOC_IDA_WAKE_ONLY: Hybrid allocation where wake-capable devices rely on
• • IDA-based allocation and range [ida_min, 11], while regular devices rely on default
• • allocation in range [1, ida_min - 1]
  */

enum sdw_dev_num_alloc { SDW_DEV_NUM_ALLOC_DEFAULT = 0, SDW_DEV_NUM_ALLOC_IDA,

• SDW_DEV_NUM_ALLOC_IDA_WAKE_ONLY,

};

/**

2.25.1