[PATCH v2 0/4] USB3503: correct GPIOs polarity and update the driver

From: Marek Szyprowski <m.szyprowski@samsung.com>
To: linux-usb@vger.kernel.org, linux-samsung-soc@vger.kernel.org,
	linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org
Cc: Marek Szyprowski <m.szyprowski@samsung.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Krzysztof Kozlowski <krzk@kernel.org>,
	Matthias Brugger <matthias.bgg@gmail.com>,
	Maxime Ripard <mripard@kernel.org>, Chen-Yu Tsai <wens@csie.org>,
	Andy Gross <agross@kernel.org>,
	Bjorn Andersson <bjorn.andersson@linaro.org>,
	Stefan Agner <stefan@agner.ch>,
	Chunfeng Yun <chunfeng.yun@mediatek.com>,
	Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Subject: [PATCH v2 0/4] USB3503: correct GPIOs polarity and update the driver
Date: Wed, 11 Dec 2019 15:46:34 +0100	[thread overview]
Message-ID: <20191211144638.24676-1-m.szyprowski@samsung.com> (raw)
In-Reply-To: CGME20191211144647eucas1p23d85dee21029f864076eece98aadd525@eucas1p2.samsung.com

Dear All,

A few days ago a patch for USB3503 driver has been posted (see v1 in the
changelog below), which changes the GPIO API used by the driver to the
new one (descriptor based). It turned out that this conversion broke USB
HUB operation on some boards (observed on Arndale5250).

Further analysis revealed that the existing code ignored the GPIO
polarity flags in the device tree. On the other hand the current GPIO
polarity flags used by various boards were simply incorrect, as it was
not possible to test them properly.

This patchset provides some standardisation for the GPIO polarity flags
for USB3503 chips in various DTS files and adds matching logic to USB3503
driver. For more information and rationale behind this approach, see the
thread linked as v1 below.

This patchset has been tested on the following boards:
Odroid X2, U3, XU and Arndale5250.

The patch for USB3503 driver should be merged one release later than the
DTS changes to keep the affected boards working in meantime.

Best regards
Marek Szyprowski
Samsung R&D Institute Poland

Changelog:
v2:
- added DTS fixes, assumed that RESET GPIO should be ACTIVE_LOW and all
  other GPIOs ACTIVE_HIGH
- integrated a fixup for USB3503 driver inverting the logic behind the
  RESET GPIO to match the standardised GPIOs polarity

v1: https://lore.kernel.org/linux-usb/20191205145633.187511-1-linus.walleij@linaro.org/T/
- initial version, contains only USB3503 driver patch

Patch summary:

Linus Walleij (1):
  usb: usb3503: Convert to use GPIO descriptors

Marek Szyprowski (3):
  ARM: dts: exynos: Correct USB3503 GPIOs polarity
  ARM: dts: qcom: Correct USB3503 GPIOs polarity
  ARM: dts: sun8i: a83t: Correct USB3503 GPIOs polarity

 .../boot/dts/exynos4412-odroid-common.dtsi    |  2 +-
 arch/arm/boot/dts/exynos5250-arndale.dts      |  2 +-
 arch/arm/boot/dts/exynos5410-odroidxu.dts     |  2 +-
 .../dts/qcom-mdm9615-wp8548-mangoh-green.dts  |  2 +-
 .../boot/dts/sun8i-a83t-cubietruck-plus.dts   |  2 +-
 drivers/usb/misc/usb3503.c                    | 94 +++++++------------
 include/linux/platform_data/usb3503.h         |  3 -
 7 files changed, 40 insertions(+), 67 deletions(-)

-- 
2.17.1