[BUG] usb/at91: usb hub does not work

[Boris Brezillon]

Hi Jiri,

On Fri, 12 Jun 2015 11:30:20 +0200
Jiří Prchal <jiri.prchal at aksignal.cz> wrote:

> 
> 
> On 11.6.2015 15:53, Alan Stern wrote:
> > On Thu, 11 Jun 2015, Jiří Prchal wrote:
> >
> >> Hi all,
> >> I discovered some bug when I change kernel from 3.18.13 to 3.18.14. I have board with usb hub CY7C65632 on it.
> >> In .13 it works fine but in .14 it repeats this message:
> >> [   19.170000] usb 2-3: new full-speed USB device number 56 using at91_ohci
> >> and devices connected to usb through hub doesn't appear at all.
> >
> >> Any idea?
> >
> > Try using git bisect to find the commit which caused this problem to
> > start.
> 
> This is result:
> Bisecting: 0 revisions left to test after this (roughly 0 steps)
> [ae74ea64ccdb8b99ee2618b58020263d5b1d9b22] clk: at91: usb: propagate rate modification to the parent clk


Actually when bisecting you found a bug that has been fixed before
3.18.14 was released (see this commit [1]).
This being said, the prototype mismatch fix does not seem to fix all
the mismatches (seems the ->determine_rate() has been changed in 3.19
too, and the prototype mismatch patch was a backport of a 3.19 fix).

Anyway, you'll find below a patch supposed to fix the remaining bug.
Can you try to apply it and let me know if it fixes your problem.

Best Regards,

Boris

[1]https://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/commit/drivers/clk/at91/clk-usb.c?id=76723e7ed589998384a080e29204df4659c67cf2

-- >8 --

From 7392429d074f43ef61d41e33db63f0f5d804bdd4 Mon Sep 17 00:00:00 2001
Subject: [PATCH] clk: at91: fix determine_rate prototype (again)

Commit ae74ea64ccdb8b99ee2618b58020263d5b1d9b22 was a backport of a bug
fix applied in 4.0, but in the meantime the ->determine_rate() prototype
has changed, thus introduction a prototype mismatch bug in pre-4.0
kernels. This prototype mismatch was supposed to be fixed by commit
76723e7ed589998384a080e29204df4659c67cf2, which fix the bug on 3.19
kernels, but the ->determine_rate() has also changed between 3.18 and
3.19. Hopefully this patch will definitely fix the prototype mismatch
for 3.18.

Signed-off-by: Boris Brezillon <boris.brezillon at free-electrons.com>
---
 drivers/clk/at91/clk-usb.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/at91/clk-usb.c b/drivers/clk/at91/clk-usb.c
index 0283a57..d0d335d 100644
--- a/drivers/clk/at91/clk-usb.c
+++ b/drivers/clk/at91/clk-usb.c
@@ -59,7 +59,7 @@ static unsigned long
at91sam9x5_clk_usb_recalc_rate(struct clk_hw *hw, static long
at91sam9x5_clk_usb_determine_rate(struct clk_hw *hw, unsigned long rate,
 					      unsigned long
*best_parent_rate,
-					      struct clk_hw
**best_parent_hw)
+					      struct clk
**best_parent_clk) {
 	struct clk *parent = NULL;
 	long best_rate = -EINVAL;
@@ -91,7 +91,7 @@ static long at91sam9x5_clk_usb_determine_rate(struct
clk_hw *hw, best_rate = tmp_rate;
 				best_diff = tmp_diff;
 				*best_parent_rate = tmp_parent_rate;
-				*best_parent_hw = __clk_get_hw(parent);
+				*best_parent_clk = parent;
 			}
 
 			if (!best_diff || tmp_rate < rate)
-- 
1.9.1