On 07/28/2014 06:20 PM, Stefan Agner wrote: [...] > However, I got once this Kernel panic after I reconfigured to normal > mode. But I could not reproduce this. > > [ 461.954394] flexcan_irq, esr=00059d82 > [ 461.958093] flexcan_irq, ctrl=17092051 > [ 461.961873] ------------[ cut here ]------------ > [ 461.966536] WARNING: CPU: 0 PID: 0 at kernel/locking/mutex.c:826 > mutex_trylock+0x1b0/0x208() > [ 461.974982] DEBUG_LOCKS_WARN_ON(in_interrupt())
Please use this updated version of your patch:
Marc
---
From b6b8ae7cdb04f1a3b9d3a6dd83f8146bfaf48553 Mon Sep 17 00:00:00 2001
From: Stefan Agner <ste...@agner.ch>
Date: Tue, 15 Jul 2014 14:56:20 +0200
Subject: [PATCH] can: flexcan: flexcan_get_berr_counter(): switch on clocks
before accessing ecr register
The funcion flexcan_get_berr_counter() may be called from userspace even if the
interface is down, this the clocks are disabled. This patch switches on the
clocks before accessing the ecr register.
Reported-by: Ashutosh Singh <ashuleapy...@gmail.com>
Signed-off-by: Stefan Agner <ste...@agner.ch>
Signed-off-by: Marc Kleine-Budde <m...@pengutronix.de>
---
drivers/net/can/flexcan.c | 30 +++++++++++++++++++++++++++---
1 file changed, 27 insertions(+), 3 deletions(-)
diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c
index f425ec2..6bfe24a 100644
--- a/drivers/net/can/flexcan.c
+++ b/drivers/net/can/flexcan.c
@@ -378,8 +378,9 @@ static int flexcan_chip_softreset(struct flexcan_priv *priv)
return 0;
}
-static int flexcan_get_berr_counter(const struct net_device *dev,
- struct can_berr_counter *bec)
+
+static int __flexcan_get_berr_counter(const struct net_device *dev,
+ struct can_berr_counter *bec)
{
const struct flexcan_priv *priv = netdev_priv(dev);
struct flexcan_regs __iomem *regs = priv->base;
@@ -391,6 +392,29 @@ static int flexcan_get_berr_counter(const struct
net_device *dev,
return 0;
}
+static int flexcan_get_berr_counter(const struct net_device *dev,
+ struct can_berr_counter *bec)
+{
+ const struct flexcan_priv *priv = netdev_priv(dev);
+ int 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;
+
+ err = __flexcan_get_berr_counter(dev, bec);
+
+ clk_disable_unprepare(priv->clk_per);
+ out_disable_ipg:
+ clk_disable_unprepare(priv->clk_ipg);
+
+ return err;
+}
+
static int flexcan_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
const struct flexcan_priv *priv = netdev_priv(dev);
@@ -503,7 +527,7 @@ static void do_state(struct net_device *dev,
struct flexcan_priv *priv = netdev_priv(dev);
struct can_berr_counter bec;
- flexcan_get_berr_counter(dev, &bec);
+ __flexcan_get_berr_counter(dev, &bec);
switch (priv->can.state) {
case CAN_STATE_ERROR_ACTIVE:
--
2.0.1
--
Pengutronix e.K. | Marc Kleine-Budde |
Industrial Linux Solutions | Phone: +49-231-2826-924 |
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