From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Warren <swarren@wwwdotorg.org>
Date: Wed, 20 Jun 2012 10:41:52 -0600
Subject: [U-Boot] [PATCH v3 1/1] tegra: usb: Fix device enumeration
 problem of USB1
In-Reply-To: <4B9C9637D5087840A465BDCB251780E9E2D6EDA3E5@HKMAIL02.nvidia.com>
References: <4B9C9637D5087840A465BDCB251780E9E2D6EDA3E5@HKMAIL02.nvidia.com>
Message-ID: <4FE1FD50.1020607@wwwdotorg.org>
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To: u-boot@lists.denx.de

On 06/20/2012 03:15 AM, Jim Lin wrote:
> A known hardware issue of USB1 port where bit 1 (connect status
> change) of PORTSC register will be set after issuing Port Reset
> (like "usb reset" in u-boot command line).
> This will be treated as an error and stops later device enumeration.
> 
> Therefore we clear that bit after Port Reset in order to proceed
> later device enumeration.
> 
> Signed-off-by: Jim Lin <jilin@nvidia.com>

Acked-by: Stephen Warren <swarren@wwwdotorg.org>

But a couple of nits below,

> diff --git a/drivers/usb/host/ehci-tegra.c b/drivers/usb/host/ehci-tegra.c

> +/*
> + * A known hardware issue where Connect Status Change bit of PORTSC register
> + * of USB1 controller will be set after Port Reset.
> + * We have to clear it in order for later device enumeration to proceed.
> + */

It might be worth adding a note in that comment saying that this
overrides a weak symbol in ehci-hcd.c so that people know where it's called.

> +void ehci_powerup_fixup(uint32_t *status_reg, uint32_t *reg)
> +{
> +	uint32_t my_reg;

I would rename this variable just "reg"; the variable doesn't belong to
a person, and names with "my" in just make me cringe.