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

From: Marc Kleine-Budde <[email-masked]>
Date: Tue, 20 Oct 2015 16:46:37 +0200

On 10/20/2015 04:39 PM, Anton Glukhov wrote:
> This patch fixes a warning in clk_enable by calling
> clk_prepare_enable instead.
> 
> Signed-off-by: Heiko Schocher <[email-masked]>
> Signed-off-by: Anton Glukhov <[email-masked]>
> ---
>  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

>  	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()?

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

The NULLing of priv->clk is not needed.

>  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()?

> +	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.

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

Marc
-- 
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