Re: [PATCH v4 0/6] thunderbolt: CL1 support for USB4 and Titan Ridge

[Mika Westerberg <mika.westerberg@linux.intel.com>]

Hi Gil,

On Thu, May 26, 2022 at 01:59:15PM +0300, Gil Fine wrote:
> v1 can be found here:
>   https://lore.kernel.org/linux-usb/20220501203321.19021-1-gil.fine@intel.com/
> v2 can be found here:
>   https://lore.kernel.org/linux-usb/20220509201656.502-1-gil.fine@intel.com/
> v3 can be found here:
>   https://lore.kernel.org/linux-usb/20220511140549.10571-1-gil.fine@intel.com/
> 
> Changes in v4:
> * Remove unnecessary struct tb_sw_tmu_config and fix some typos.
> * device_for_each_child() move from tb.c to tmu.c
>   inside tb_switch_enable_tmu_1st_child().
> 
> Changes in v3:
> * Fix to support the case of enabling CL1 entry after resume
>   from runtime PM (if CL1 supported in the connected device)
> 
> Changes in v2:
> * Handle CL1 and CL0s together since on the hardware level they are
>   supported and enabled together
> * Use device_for_each_child() to set TMU mode of host router's 1st
>   children
> * Use FIELD_x macros from include/linux/bitfield.h
> * Split single patch into two for clarity
> * Fix commit message
> 
> In this series of patches, first, we address several issues in the CL0s
> implementation.
> Then, we add support for a second low power state of the
> link: CL1. Low power states (called collectively CLx) are used to reduce
> transmitter and receiver power when a high-speed lane is idle.
> We enable it, if both sides of the link support it, and only for the
> first hop router (i.e. the first device that connected to the
> host router). This is needed for better thermal management.
> CL1 improves power management that was intoduced by CL0s.
> Also, we add support of dynamic change of TMU mode to HiFi uni-directional
> once DisplayPort tunnel is created.
> This enables CL0s while DP tunnel exists.
> Due to Intel hardware limitation, once we changed the TMU mode to HiFi
> uni-directional (when DP tunnel exists), we don't change TMU mode back
> to normal uni-directional, even if DP tunnel is torn down later.
> Though, after sleep (or runtime PM) resume, the TMU is changed to normal
> uni-directional (if CLx supported in the connected device) to enable
> CL1 entry.
> 
> Gil Fine (6):
>   thunderbolt: Silently ignore CLx enabling in case CLx is not supported
>   thunderbolt: CLx disable before system suspend only if previously
>     enabled
>   thunderbolt: Fix typos in CLx enabling
>   thunderbolt: Change downstream router's TMU rate in both TMU uni/bidir
>     mode
>   thunderbolt: Add CL1 support for USB4 and Titan Ridge routers
>   thunderbolt: Change TMU mode to HiFi uni-directional once DisplayPort
>     tunneled

All applied to thunderbolt.git/next, thanks!

I changed "Unknown" to "unknown" in tb_switch_clx_name() to be
consistent with the rest of the driver.