[U-Boot] [RFC PATCH v2 2/3] net: ag7xxx: Propagate errors on phy access

[Marek Vasut]

On 06/26/2017 09:40 PM, Joe Hershberger wrote:
> Don't wait forever.
> Pass errors back to the caller.
> 
> Signed-off-by: Joe Hershberger <joe.hershberger at ni.com>

Acked-by: Marek Vasut <marex at denx.de>

> ---
> 
> Changes in v2:
> - Isolate error propagation changes
> 
>  drivers/net/ag7xxx.c | 29 ++++++++++++++++++++++++-----
>  1 file changed, 24 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/net/ag7xxx.c b/drivers/net/ag7xxx.c
> index 30771b9..00e6806 100644
> --- a/drivers/net/ag7xxx.c
> +++ b/drivers/net/ag7xxx.c
> @@ -285,18 +285,33 @@ static int ag7xxx_switch_reg_write(struct mii_dev *bus, int reg, u32 val)
>  	return 0;
>  }
>  
> -static u16 ag7xxx_mdio_rw(struct mii_dev *bus, int addr, int reg, u32 val)
> +static int ag7xxx_mdio_rw(struct mii_dev *bus, int addr, int reg, u32 val)
>  {
>  	u32 data;
> +	unsigned long start;
> +	int ret;
> +	/* No idea if this is long enough or too long */
> +	int timeout_ms = 1000;
>  
>  	/* Dummy read followed by PHY read/write command. */
> -	ag7xxx_switch_reg_read(bus, 0x98, &data);
> +	ret = ag7xxx_switch_reg_read(bus, 0x98, &data);
> +	if (ret < 0)
> +		return ret;
>  	data = val | (reg << 16) | (addr << 21) | BIT(30) | BIT(31);
> -	ag7xxx_switch_reg_write(bus, 0x98, data);
> +	ret = ag7xxx_switch_reg_write(bus, 0x98, data);
> +	if (ret < 0)
> +		return ret;
> +
> +	start = get_timer(0);
>  
>  	/* Wait for operation to finish */
>  	do {
> -		ag7xxx_switch_reg_read(bus, 0x98, &data);
> +		ret = ag7xxx_switch_reg_read(bus, 0x98, &data);
> +		if (ret < 0)
> +			return ret;
> +
> +		if (get_timer(start) > timeout_ms)
> +			return -ETIMEDOUT;
>  	} while (data & BIT(31));
>  
>  	return data & 0xffff;
> @@ -310,7 +325,11 @@ static int ag7xxx_mdio_read(struct mii_dev *bus, int addr, int devad, int reg)
>  static int ag7xxx_mdio_write(struct mii_dev *bus, int addr, int devad, int reg,
>  			     u16 val)
>  {
> -	ag7xxx_mdio_rw(bus, addr, reg, val);
> +	int ret;
> +
> +	ret = ag7xxx_mdio_rw(bus, addr, reg, val);
> +	if (ret < 0)
> +		return ret;
>  	return 0;
>  }
>  
> 


-- 
Best regards,
Marek Vasut