Re: [PATCH 0/4] ARM: DRA7: Fix DCAN1 stuck-in-transition

[Roger Quadros]

On 13/03/17 13:53, Roger Quadros wrote:
> Hi,
> 
> On DRA7 platform, DCAN1 module has an issue when it's clockdomain
> (WKUPAON) is configured in HW_AUTO. After DCAN1 is enabled and disabled
> the module remains stuck in transition.
> 
> Suggested workaround by Silicon team is to disable HW_AUTO for
> WKUPAON clockdomain when DCAN1 module is active.
> 
> These patches provide a new flag for hwmod data to support this
> behaviour and fix up dra7 hwmod data as well to fix this issue
> on dra7x-evms.
> 
> This patch allows DCAN1 to be functional as well as not prevent
> Core Retention as WKUPAON clockdomain is put back into HW_AUTO
> whenever DCAN1 is not active (e.g. runtime suspended).
> 
> Without this series, we can see the following warning messages
> when the CAN interface is brought up and down.
> 
> ~# ifconfig can0 up
> [   36.418299] net can0: c_can_hw_raminit_wait_syscon: time out
> [   36.424642] c_can_platform 4ae3c000.can can0: setting BTR=1c04 BRPE=0000
> ~# ifconfig can0 down
> [   50.488786] omap_hwmod: dcan1: _wait_target_disable failed
> [   50.502855] omap_hwmod: dcan1: _wait_target_disable failed

Forgot to mention that usb_otg_ss modules are also having
similar behaviour and patch 4 addresses that.

> 
> cheers,
> -roger
> 
> Roger Quadros (3):
>   ARM: OMAP2+ hwmod: Allow modules to disable HW_AUTO
>   ARM: DRA7: hwmod: Fix DCAN1 stuck in transition
>   ARM: DRA7: hwmod_data: Prevent wait_target_disable error for
>     usb_otg_ss
> 
> Sekhar Nori (1):
>   ARM: OMAP2+: omap_hwmod: provide space for more hwmod flags
> 
>  arch/arm/mach-omap2/omap_hwmod.c          | 4 ++--
>  arch/arm/mach-omap2/omap_hwmod.h          | 7 ++++++-
>  arch/arm/mach-omap2/omap_hwmod_7xx_data.c | 4 ++++
>  3 files changed, 12 insertions(+), 3 deletions(-)
> 

-- 
cheers,
-roger