From: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>
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.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>
Reviewed-by: Rander Wang <rander.wang@xxxxxxxxx>
Signed-off-by: Bard Liao <yung-chuan.liao@xxxxxxxxxxxxxxx>
---
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
