Re: [PATCH 4/7] soundwire: intel: add definitions for shim_mask

Pierre-Louis Bossart
2020-03-20T18:18:00Z

>> diff --git a/drivers/soundwire/intel.h b/drivers/soundwire/intel.h
>> index 568c84a80d79..cfc83120b8f9 100644
>> --- a/drivers/soundwire/intel.h
>> +++ b/drivers/soundwire/intel.h
>> @@ -16,6 +16,7 @@
>> * @ops: Shim callback ops
>> * @dev: device implementing hw_params and free callbacks
>> * @shim_lock: mutex to handle access to shared SHIM registers
>> + * @shim_mask: global pointer to check SHIM register initialization
>> */
>> struct sdw_intel_link_res {
>> struct platform_device *pdev;
>> @@ -27,6 +28,7 @@ struct sdw_intel_link_res {
>> const struct sdw_intel_ops *ops;
>> struct device *dev;
>> struct mutex *shim_lock; /* protect shared registers */
>> + u32 *shim_mask;
>
> You have a pointer, okay where is it initialized

same answer as shim_lock, it's initialized at the higher level

https://github.com/thesofproject/linux/blob/9c7487b33072040ab755d32ca173b75151c0160c/drivers/soundwire/intel_init.c#L252

>> };
>>
>> #endif /* __SDW_INTEL_LOCAL_H */
>> diff --git a/include/linux/soundwire/sdw_intel.h b/include/linux/soundwire/sdw_intel.h
>> index 979b41b5dcb4..120ffddc03d2 100644
>> --- a/include/linux/soundwire/sdw_intel.h
>> +++ b/include/linux/soundwire/sdw_intel.h
>> @@ -115,6 +115,7 @@ struct sdw_intel_slave_id {
>> * links
>> * @link_list: list to handle interrupts across all links
>> * @shim_lock: mutex to handle concurrent rmw access to shared SHIM registers.
>> + * @shim_mask: flags to track initialization of SHIM shared registers
>> */
>> struct sdw_intel_ctx {
>> int count;
>> @@ -126,6 +127,7 @@ struct sdw_intel_ctx {
>> struct sdw_intel_slave_id *ids;
>> struct list_head link_list;
>> struct mutex shim_lock; /* lock for access to shared SHIM registers */
>> + u32 shim_mask;
>
> And a integer, question: why do you need pointer and integer, why not
> use only one..?

You may have missed that the structures are different.

the sdw_intel_ctx is global for all links, so that the shim_mask integer
value.
the sdw_intel_link_res is link-specific and use a pointer to the same
shim_mask value, protected by shim_lock.