lkml.org 
[lkml]   [2017]   [Nov]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] usb: ulpi: Add missing of_node_get() in ulpi_of_register()
On Fri, Nov 10, 2017 at 05:43:00PM -0800, Stephen Boyd wrote:
> In ulpi_of_register() we call of_find_node_by_name() which
> unconditionally calls of_node_put() on the 'from' argument. We
> haven't called of_node_get() though, so we've put the node once
> without getting it first. Add the of_node_get() call so that
> things are properly balanced.
>
> Fixes: ef6a7bcfb01c ("usb: ulpi: Support device discovery via DT")
> Reported-by: Peter Robinson <pbrobinson@gmail.com>
> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
> ---
> drivers/usb/common/ulpi.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/usb/common/ulpi.c b/drivers/usb/common/ulpi.c
> index 4aa5195db8ea..59e05eff76f9 100644
> --- a/drivers/usb/common/ulpi.c
> +++ b/drivers/usb/common/ulpi.c
> @@ -182,9 +182,9 @@ static int ulpi_of_register(struct ulpi *ulpi)
>
> /* Find a ulpi bus underneath the parent or the grandparent */
> parent = ulpi->dev.parent;
> - if (parent->of_node)
> + if (of_node_get(parent->of_node))
> np = of_find_node_by_name(parent->of_node, "ulpi");
> - else if (parent->parent && parent->parent->of_node)
> + else if (parent->parent && of_node_get(parent->parent->of_node))
> np = of_find_node_by_name(parent->parent->of_node, "ulpi");

I'm afraid this isn't the right fix; the code shouldn't have been using
of_find_node_by_name() in the first place as that function searches the
whole device tree depth-first starting at the parent (or grand parent),
which could end up matching an unrelated node.

of_get_child_by_name() is the helper to use for such lookups instead.

Turns out we have a few other driver with similar bugs. I've started
fixing a few of them that'll be sending out per subsystem.

I'll post a fix for this one as follow up to this mail meanwhile.

Thanks,
Johan

\
 
 \ /
  Last update: 2017-11-11 16:25    [W:0.084 / U:0.308 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site