Re: [PATCH v2] net, can, ti_hecc: fix a run time warn_on.

Thank you for review Marc!

On 20.10.2015 17:46, Marc Kleine-Budde wrote:

On 10/20/2015 04:39 PM, Anton Glukhov wrote:

quoted

This patch fixes a warning in clk_enable by calling
clk_prepare_enable instead.

Signed-off-by: Heiko Schocher <redacted>
Signed-off-by: Anton Glukhov <redacted>
---
 drivers/net/can/ti_hecc.c | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/drivers/net/can/ti_hecc.c b/drivers/net/can/ti_hecc.c
index cf345cb..77dd170 100644
--- a/drivers/net/can/ti_hecc.c
+++ b/drivers/net/can/ti_hecc.c

@@ -951,7 +951,7 @@ static int ti_hecc_probe(struct platform_device *pdev)
 	netif_napi_add(ndev, &priv->napi, ti_hecc_rx_poll,
 		HECC_DEF_NAPI_WEIGHT);
 
-	clk_enable(priv->clk);
+	clk_prepare_enable(priv->clk);

please add error checking

quoted

 	err = register_candev(ndev);
 	if (err) {
 		dev_err(&pdev->dev, "register_candev() failed\n");

@@ -966,7 +966,8 @@ static int ti_hecc_probe(struct platform_device *pdev)
 	return 0;
 
 probe_exit_clk:
-	clk_put(priv->clk);

Why do you remove the clk_put()?

My fault. I'll fix it in ver3.

quoted

+	clk_disable_unprepare(priv->clk);
+	priv->clk = NULL;

The NULLing of priv->clk is not needed.

quoted

 probe_exit_candev:
 	free_candev(ndev);
 probe_exit_iounmap:

@@ -984,8 +985,8 @@ static int ti_hecc_remove(struct platform_device *pdev)
 	struct ti_hecc_priv *priv = netdev_priv(ndev);
 
 	unregister_candev(ndev);
-	clk_disable(priv->clk);
-	clk_put(priv->clk);

Why do you remoe the clk_put()?

quoted

+	clk_disable_unprepare(priv->clk);
+	priv->clk = NULL;
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	iounmap(priv->base);
 	release_mem_region(res->start, resource_size(res));

@@ -1009,7 +1010,7 @@ static int ti_hecc_suspend(struct platform_device *pdev, pm_message_t state)
 	hecc_set_bit(priv, HECC_CANMC, HECC_CANMC_PDR);
 	priv->can.state = CAN_STATE_SLEEPING;
 
-	clk_disable(priv->clk);
+	clk_disable_unprepare(priv->clk);
 
 	return 0;
 }

@@ -1019,7 +1020,7 @@ static int ti_hecc_resume(struct platform_device *pdev)
 	struct net_device *dev = platform_get_drvdata(pdev);
 	struct ti_hecc_priv *priv = netdev_priv(dev);
 
-	clk_enable(priv->clk);
+	clk_prepare_enable(priv->clk);

please add error checking.

Why it wasn't added with clk_enable? Is it bug? I'm confused here, because in so many drivers
there is no checking err after clk_enable or clk_prepare_enable. Maybe I missed something...
Could you clarify this part please?

quoted

 
 	hecc_clear_bit(priv, HECC_CANMC, HECC_CANMC_PDR);
 	priv->can.state = CAN_STATE_ERROR_ACTIVE;

Marc

regards,
Anton