[PATCH v2] can: Fix bug in suspend/resume

From: Kedareswara rao Appana
Date: Fri Nov 14 2014 - 03:16:40 EST


The drvdata in the suspend/resume is of type struct net_device,
not the platform device.Enable the clocks in the suspend before
accessing the registers of the CAN.

Signed-off-by: Kedareswara rao Appana <appanad@xxxxxxxxxx>
---
Changes for v2:
- Removed the struct platform_device* from suspend/resume
as suggest by Lothar.
- The clocks are getting disabled and un prepared at the end of the probe.
In the suspend the driver is doing a register write.In order
To do that register write we have to again enable and prepare the clocks.


drivers/net/can/xilinx_can.c | 20 ++++++++++++++++----
1 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/drivers/net/can/xilinx_can.c b/drivers/net/can/xilinx_can.c
index 5e8b560..485262f 100644
--- a/drivers/net/can/xilinx_can.c
+++ b/drivers/net/can/xilinx_can.c
@@ -972,15 +972,28 @@ static const struct net_device_ops xcan_netdev_ops = {
*/
static int __maybe_unused xcan_suspend(struct device *dev)
{
- struct platform_device *pdev = dev_get_drvdata(dev);
- struct net_device *ndev = platform_get_drvdata(pdev);
+ struct net_device *ndev = dev_get_drvdata(dev);
struct xcan_priv *priv = netdev_priv(ndev);
+ int ret;

if (netif_running(ndev)) {
netif_stop_queue(ndev);
netif_device_detach(ndev);
}

+ ret = clk_prepare_enable(priv->can_clk);
+ if (ret) {
+ dev_err(dev, "unable to enable device clock\n");
+ return ret;
+ }
+
+ ret = clk_prepare_enable(priv->bus_clk);
+ if (ret) {
+ dev_err(dev, "unable to enable bus clock\n");
+ clk_disable_unprepare(priv->can_clk);
+ return ret;
+ }
+
priv->write_reg(priv, XCAN_MSR_OFFSET, XCAN_MSR_SLEEP_MASK);
priv->can.state = CAN_STATE_SLEEPING;

@@ -999,8 +1012,7 @@ static int __maybe_unused xcan_suspend(struct device *dev)
*/
static int __maybe_unused xcan_resume(struct device *dev)
{
- struct platform_device *pdev = dev_get_drvdata(dev);
- struct net_device *ndev = platform_get_drvdata(pdev);
+ struct net_device *ndev = dev_get_drvdata(dev);
struct xcan_priv *priv = netdev_priv(ndev);
int ret;

--
1.7.4

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