All of lore.kernel.org
 help / color / mirror / Atom feed
From: Stephen Warren <swarren@wwwdotorg.org>
To: u-boot@lists.denx.de
Subject: [U-Boot] [PATCH v3 1/1] tegra: usb: Fix device enumeration problem of USB1
Date: Wed, 20 Jun 2012 10:41:52 -0600	[thread overview]
Message-ID: <4FE1FD50.1020607@wwwdotorg.org> (raw)
In-Reply-To: <4B9C9637D5087840A465BDCB251780E9E2D6EDA3E5@HKMAIL02.nvidia.com>

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.

      reply	other threads:[~2012-06-20 16:41 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-06-20  9:15 [U-Boot] [PATCH v3 1/1] tegra: usb: Fix device enumeration problem of USB1 Jim Lin
2012-06-20 16:41 ` Stephen Warren [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=4FE1FD50.1020607@wwwdotorg.org \
    --to=swarren@wwwdotorg.org \
    --cc=u-boot@lists.denx.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.