On 17-12-19, 15:03, Pierre-Louis Bossart wrote:
In the existing SoundWire code, the bus does not have any explicit representation for Master Devices - only SoundWire Slaves are exposed.
In SoundWire, the Master Device provides the clock, synchronization information and command/control channels. When multiple links are supported, a Controller may expose more than one Master Device; they are typically embedded inside a larger audio cluster (be it in an SOC/chipset or an external audio codec), and we need to describe it using the Linux device and driver model. This will allow for configuration functions to account for external dependencies such as power rails, clock sources or wake-up mechanisms. This transition will also allow for better sysfs support without the reference count issues mentioned in the initial reviews.
In this patch, we first convert the existing code to use an explicit sdw_slave_type and add error checks if this type is not set.
In follow-up patches we can add support for the sdw_master_type.
Signed-off-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com
drivers/soundwire/bus_type.c | 23 ++++++++++++++++++----- drivers/soundwire/slave.c | 7 ++++++- include/linux/soundwire/sdw_type.h | 6 ++++++ 3 files changed, 30 insertions(+), 6 deletions(-)
diff --git a/drivers/soundwire/bus_type.c b/drivers/soundwire/bus_type.c index 9a0fd3ee1014..9719680a1e48 100644 --- a/drivers/soundwire/bus_type.c +++ b/drivers/soundwire/bus_type.c @@ -49,13 +49,26 @@ int sdw_slave_modalias(const struct sdw_slave *slave, char *buf, size_t size)
static int sdw_uevent(struct device *dev, struct kobj_uevent_env *env) {
- struct sdw_slave *slave = to_sdw_slave_device(dev);
- struct sdw_slave *slave; char modalias[32];
- sdw_slave_modalias(slave, modalias, sizeof(modalias));
- if (add_uevent_var(env, "MODALIAS=%s", modalias))
return -ENOMEM;
- if (is_sdw_slave(dev)) {
slave = to_sdw_slave_device(dev);sdw_slave_modalias(slave, modalias, sizeof(modalias));if (add_uevent_var(env, "MODALIAS=%s", modalias))return -ENOMEM;- } else {
/** We only need to handle uevents for the Slave device* type. This error cannot happen unless the .uevent* callback is set to use this function for a* different device type (e.g. Master or Monitor)*/dev_err(dev, "uevent for unknown Soundwire type\n");return -EINVAL;
At this point and after next patch, the above code would be a no-op, do we want this here, if so why?