Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1211845

Re: [PATCH 0/7] Exynos4412-based Trats2 USB gadget (DWC2) fixes

Show all headers | View raw

On 21.08.2015 21:38, Marek Szyprowski wrote:
> Dear All,
> 
> Since v3.19 s3c-hsotg (DWC2) USB controller stopped working on
> Exynos4412-based Trats2 platform. However on Odroid-U3 (which is also
> Exynos4412-based) it worked fine all the time. After long investigation
> it turned out that this was caused by 2 independent issues.
> 
> First issue was caused by patch 7eec1266751bd3a25e35ce88686634c768fedc24
> ("ARM: dts: Add Maxim 77693 PMIC to exynos4412-trats2") added support
> for Maxim 77693 regulators, but without defining consumers for them.
> This causes regulator core to disable them. However SAFEOUT1 regulator
> provides power supply to VBUS signal, which also power some USB phy
> related parts of Exynos SoC core. This has been fixed by patches 1-3,
> which adds support for VBUS regulator, defines them in DTS for all
> Exynos platforms and changes probe sequence of the drivers to ensure no
> deferred probe occurs (USB gadget subsystem doesn't support deferred
> probe yet).
> 
> Second issue is related to DWC2 driver rewrite and host/gadget/dual-role
> integration code. DWC2 module on some platforms needs three additional
> hardware resources: phy, clock and power supply. All of them must be
> enabled/activated to properly initialize and operate. This was initially
> handled in s3c-hsotg driver, which has been converted to 'gadget' part
> of dwc2 driver. Unfortunately, not all of this code got moved to common
> platform code, what resulted in accessing DWC2 registers without
> enabling power supply regulators and clock. This caused initialization
> failure on Exynos4412-based Trats2. Odroid U3 board worked fine, because
> power supplies used by DWC2 module are marked there as 'always-on',
> because they are also used by other modules (USB hub) and clock was
> shared with USB2 PHY, so it was already enabled. This initialization
> issue has been fixed by the last patch. While preparing it I've also
> fixed a few minor issues found in nearby code (patches 4-6).
> 
> I would like to get those patches merged separately to respective
> subsystem trees:
> patch 1: phy subsystem tree
> patch 2: Samsung Exynos tree
> patch 3: regulator subsystem tree
> patch 4-7: USB gadget subsystem tree
> 
> Patches have been prepared on top of linux-next from 20150821.

Entire patchset tested on Trats2 board:
Tested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>

Best regards,
Krzysztof

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Back to linux.kernel | Previous | Next — Previous in thread | Find similar | Unroll thread

Thread

[PATCH 0/7] Exynos4412-based Trats2 USB gadget (DWC2) fixes Marek Szyprowski <m.szyprowski@samsung.com> - 2015-08-21 14:50 +0200
  [PATCH 4/7] usb: dwc2: remove double call to s3c_hsotg_of_probe Marek Szyprowski <m.szyprowski@samsung.com> - 2015-08-21 14:50 +0200
  [PATCH 7/7] usb: dwc2: refactor common low-level hw code to platform.c Marek Szyprowski <m.szyprowski@samsung.com> - 2015-08-21 14:50 +0200
    Re: [PATCH 7/7] usb: dwc2: refactor common low-level hw code to  platform.c John Youn <John.Youn@synopsys.com> - 2015-09-03 03:20 +0200
  [PATCH 3/7] regulators: max77693: register driver earlier to avoid  deferred probe Marek Szyprowski <m.szyprowski@samsung.com> - 2015-08-21 14:50 +0200
    Re: [PATCH 3/7] regulators: max77693: register driver earlier to  avoid deferred probe Krzysztof Kozlowski <k.kozlowski@samsung.com> - 2015-08-23 06:00 +0200
  Re: [PATCH 0/7] Exynos4412-based Trats2 USB gadget (DWC2) fixes Krzysztof Kozlowski <k.kozlowski@samsung.com> - 2015-08-24 09:20 +0200

csiph-web