Re: [RFC PATCH] Soundwire: Initialize multi_link with fwnode props

On 8/14/22 15:45, Greg KH wrote:

On Sun, Aug 14, 2022 at 02:04:15PM +0600, Khalid Masum wrote:

...

According to the TODO, In sw_bus_master_add, bus->multi_link is to be populated with properties from FW node props. Make this happen by creating a new fwnode_handle flag FWNODE_FLAG_MULTI_LINKED and use the flag to store the multi_link value from intel_link_startup. Use this flag to initialize bus->multi_link.

Signed-off-by: Khalid Masum khalid.masum.92@gmail.com

I do not think adding a new flag for fwnode_handle is a good idea. So, what would be the best way to initialize bus->multilink with fwnode props?

-- Khalid Masum

drivers/soundwire/bus.c | 4 ++-- drivers/soundwire/intel.c | 1 + include/linux/fwnode.h | 1 + 3 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c index a2bfb0434a67..80df1672c60b 100644 --- a/drivers/soundwire/bus.c +++ b/drivers/soundwire/bus.c @@ -74,9 +74,9 @@ int sdw_bus_master_add(struct sdw_bus *bus, struct device *parent,

/* * Initialize multi_link flag

• * TODO: populate this flag by reading property from FW node
  

  */
• bus->multi_link = false;

• bus->multi_link = (fwnode->flags & FWNODE_FLAG_MULTI_LINKED)

• == FWNODE_FLAG_MULTI_LINKED;
  

  if (bus->ops->read_prop) { ret = bus->ops->read_prop(bus); if (ret < 0) {

diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c index 505c5ef061e3..034d1c523ddf 100644 --- a/drivers/soundwire/intel.c +++ b/drivers/soundwire/intel.c @@ -1347,6 +1347,7 @@ int intel_link_startup(struct auxiliary_device *auxdev) */ bus->multi_link = true; bus->hw_sync_min_links = 1;

• dev->fwnode->flags |= FWNODE_FLAG_MULTI_LINKED;
  

  }

  /* Initialize shim, controller */

diff --git a/include/linux/fwnode.h b/include/linux/fwnode.h index 9a81c4410b9f..446a52744953 100644 --- a/include/linux/fwnode.h +++ b/include/linux/fwnode.h @@ -32,6 +32,7 @@ struct device; #define FWNODE_FLAG_NOT_DEVICE BIT(1) #define FWNODE_FLAG_INITIALIZED BIT(2) #define FWNODE_FLAG_NEEDS_CHILD_BOUND_ON_ADD BIT(3) +#define FWNODE_FLAG_MULTI_LINKED BIT(4)

What does this commit actually change?

The new flag will lets us save if the device has multilink in fwnode_handle whenever needed. Then for soundwire/intel, save the multi_link flag into fwnode during startup. Later at master_add, as written in todo, initialize the multilink flag with fwnode's flag property.

Did you test this on real hardware?

I did not test this on real hardware.

thanks,

greg k-h

thanks, -- Khalid Masum