From mboxrd@z Thu Jan  1 00:00:00 1970
From: maxime.coquelin@st.com (Maxime Coquelin)
Date: Fri, 9 Jan 2015 15:44:56 +0100
Subject: [PATCH] reset: sunxi: fix spinlock initialization
In-Reply-To: <54AFC2A8.1010807@st.com>
References: <1420678479-630-1-git-send-email-tyler.baker@linaro.org>
 <54AFC2A8.1010807@st.com>
Message-ID: <54AFE968.4010805@st.com>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

With Maxime in the To: list.


On 01/09/2015 12:59 PM, Maxime Coquelin wrote:
> Hi Tyler, Maxime,
>
> On 01/08/2015 01:54 AM, Tyler Baker wrote:
>> Call spin_lock_init() before the spinlocks are used, preventing a 
>> lockdep
>> splat.
>>
>> I have been observing lockdep complaining [1] during boot on my a80 
>> optimus [2]
>> when CONFIG_PROVE_LOCKING has been enabled. This patch resolves the 
>> splat,
>> and has been tested on a few other sunxi platforms without issue.
>>
>> [1] 
>> http://storage.kernelci.org/next/next-20150107/arm-multi_v7_defconfig+CONFIG_PROVE_LOCKING=y/lab-tbaker/boot-sun9i-a80-optimus.html
>> [2] http://kernelci.org/boot/?a80-optimus
>>
>> Signed-off-by: Tyler Baker <tyler.baker@linaro.org>
>> ---
>> This patch was tested on 3.19.0-rc3
>>
>>   drivers/reset/reset-sunxi.c | 2 ++
>>   1 file changed, 2 insertions(+)
>>
>> diff --git a/drivers/reset/reset-sunxi.c b/drivers/reset/reset-sunxi.c
>> index eebc52c..e37250c 100644
>> --- a/drivers/reset/reset-sunxi.c
>> +++ b/drivers/reset/reset-sunxi.c
>> @@ -157,6 +157,8 @@ static int sunxi_reset_probe(struct 
>> platform_device *pdev)
>>       if (IS_ERR(data->membase))
>>           return PTR_ERR(data->membase);
>>   +    spin_lock_init(&data->lock);
>> +
> Shouldn't the lock be initialized also in early init function 
> (sunxi_reset_init) ?
>
> Regards,
> Maxime
>>       data->rcdev.owner = THIS_MODULE;
>>       data->rcdev.nr_resets = resource_size(res) * 32;
>>       data->rcdev.ops = &sunxi_reset_ops;
>