net: macb: Only call GPIO functions if there is a valid GPIO

GPIOlib will print warning messages if we call GPIO functions without a
valid GPIO. Change the code to avoid doing so.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
---
 drivers/net/ethernet/cadence/macb.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

From: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Date: Mon, 28 Mar 2016 13:47:42 +0100

> GPIOlib will print warning messages if we call GPIO functions without a
> valid GPIO. Change the code to avoid doing so.
> 
> Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>

Applied.

Hello.

On 03/28/2016 03:47 PM, Charles Keepax wrote:

> GPIOlib will print warning messages if we call GPIO functions without a
> valid GPIO. Change the code to avoid doing so.
>
> Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
> ---
>   drivers/net/ethernet/cadence/macb.c | 8 +++++---
>   1 file changed, 5 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/net/ethernet/cadence/macb.c b/drivers/net/ethernet/cadence/macb.c
> index 6619178..71bb42e 100644
> --- a/drivers/net/ethernet/cadence/macb.c
> +++ b/drivers/net/ethernet/cadence/macb.c
> @@ -2957,9 +2957,10 @@ static int macb_probe(struct platform_device *pdev)
>   	phy_node =  of_get_next_available_child(np, NULL);
>   	if (phy_node) {
>   		int gpio = of_get_named_gpio(phy_node, "reset-gpios", 0);
> -		if (gpio_is_valid(gpio))
> +		if (gpio_is_valid(gpio)) {
>   			bp->reset_gpio = gpio_to_desc(gpio);
> -		gpiod_direction_output(bp->reset_gpio, 1);
> +			gpiod_direction_output(bp->reset_gpio, 1);
> +		}

    Oops, sorry for missing this while fixing this code.

>   	}
>   	of_node_put(phy_node);
>
> @@ -3029,7 +3030,8 @@ static int macb_remove(struct platform_device *pdev)
>   		mdiobus_free(bp->mii_bus);
>
>   		/* Shutdown the PHY if there is a GPIO reset */
> -		gpiod_set_value(bp->reset_gpio, 0);
> +		if (bp->reset_gpio)
> +			gpiod_set_value(bp->reset_gpio, 0);

    Hm, this function was previously OK to call with NULL (it didn't curse)...

>
>   		unregister_netdev(dev);
>   		clk_disable_unprepare(bp->tx_clk);

MBR, Sergei

On Mon, Mar 28, 2016 at 08:30:11PM +0300, Sergei Shtylyov wrote:
> >@@ -3029,7 +3030,8 @@ static int macb_remove(struct platform_device *pdev)
> >  		mdiobus_free(bp->mii_bus);
> >
> >  		/* Shutdown the PHY if there is a GPIO reset */
> >-		gpiod_set_value(bp->reset_gpio, 0);
> >+		if (bp->reset_gpio)
> >+			gpiod_set_value(bp->reset_gpio, 0);
> 
>    Hm, this function was previously OK to call with NULL (it didn't curse)...
> 

Looks like it was changed so that it does complain fairly
recently (patch librally snipped down):

commit fdeb8e1547cb9dd39d5d7223b33f3565cf86c28e
Author: Linus Walleij <linus.walleij@linaro.org>

    gpio: reflect base and ngpio into gpio_device


+#define VALIDATE_DESC_VOID(desc) do { \
+ if (!desc || !desc->gdev) { \
+         pr_warn("%s: invalid GPIO\n", __func__); \
+         return; \
+ } \
+

void gpiod_set_value(struct gpio_desc *desc, int value)
{
-   if (!desc)
-           return;
+ VALIDATE_DESC_VOID(desc);

Thanks,
Charles