lkml.org 
[lkml]   [2014]   [Jul]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v3 3/4] can: flexcan: switch on clocks before accessing ecr register
On 07/15/2014 03:54 PM, Lothar Waßmann wrote:
> Hi,
>
> Stefan Agner wrote:
>> Reported-by: Ashutosh Singh <ashuleapyear@gmail.com>
>> Suggested-by: Marc Kleine-Budde <mkl@pengutronix.de>
>> [stefan@agner.ch: added return check for clk_enable_prepare]
>>
>> Signed-off-by: Stefan Agner <stefan@agner.ch>
>> ---
>> drivers/net/can/flexcan.c | 18 ++++++++++++++++--
>> 1 file changed, 16 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c
>> index f425ec2..89745aa 100644
>> --- a/drivers/net/can/flexcan.c
>> +++ b/drivers/net/can/flexcan.c
>> @@ -383,12 +383,26 @@ static int flexcan_get_berr_counter(const struct net_device *dev,
>> {
>> const struct flexcan_priv *priv = netdev_priv(dev);
>> struct flexcan_regs __iomem *regs = priv->base;
>> - u32 reg = flexcan_read(&regs->ecr);
>> + u32 reg, err;
>> +
>> + err = clk_prepare_enable(priv->clk_ipg);
>> + if (err)
>> + return err;
>> +
>> + err = clk_prepare_enable(priv->clk_per);
>> + if (err)
>> + goto out_disable_ipg;
>> +
>> + reg = flexcan_read(&regs->ecr);
>>
> flexcan_get_berr_counter() may be called from interrupt context and
> thus must not call any functions that can sleep.
> Compiling the driver with CONFIG_DEBUG_ATOMIC_SLEEP would catch this!

It's called from the NAPI softirq. I'll prepare a patch.

Marc

--
Pengutronix e.K. | Marc Kleine-Budde |
Industrial Linux Solutions | Phone: +49-231-2826-924 |
Vertretung West/Dortmund | Fax: +49-5121-206917-5555 |
Amtsgericht Hildesheim, HRA 2686 | http://www.pengutronix.de |

[unhandled content-type:application/pgp-signature]
\
 
 \ /
  Last update: 2014-07-15 19:21    [W:0.407 / U:0.812 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site