Subject: Re: [PATCH net-next v2 1/2] net: stmmac: use readl_poll_timeout() function in init_systime()

From: Andrew Lunn <[email-masked]>
Date: Sun, 15 Mar 2020 19:25:04 +0100

On Sun, Mar 15, 2020 at 11:03:00PM +0800, Dejin Zheng wrote:
> The init_systime() function use an open coded of readl_poll_timeout().
> Replace the open coded handling with the proper function.
> 
> Signed-off-by: Dejin Zheng <[email-masked]>
> ---
> v1 -> v2:
> 	- no changed.
> 
>  .../net/ethernet/stmicro/stmmac/stmmac_hwtstamp.c  | 14 ++++++--------
>  1 file changed, 6 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_hwtstamp.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_hwtstamp.c
> index 020159622559..2a24e2a7db3b 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_hwtstamp.c
> +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_hwtstamp.c
> @@ -10,6 +10,7 @@
>  *******************************************************************************/
>  
>  #include <linux/io.h>
> +#include <linux/iopoll.h>
>  #include <linux/delay.h>
>  #include "common.h"
>  #include "stmmac_ptp.h"
> @@ -53,8 +54,8 @@ static void config_sub_second_increment(void __iomem *ioaddr,
>  
>  static int init_systime(void __iomem *ioaddr, u32 sec, u32 nsec)
>  {
> -	int limit;
>  	u32 value;
> +	int err;
>  
>  	writel(sec, ioaddr + PTP_STSUR);
>  	writel(nsec, ioaddr + PTP_STNSUR);
> @@ -64,13 +65,10 @@ static int init_systime(void __iomem *ioaddr, u32 sec, u32 nsec)
>  	writel(value, ioaddr + PTP_TCR);
>  
>  	/* wait for present system time initialize to complete */
> -	limit = 10;
> -	while (limit--) {
> -		if (!(readl(ioaddr + PTP_TCR) & PTP_TCR_TSINIT))
> -			break;
> -		mdelay(10);
> -	}
> -	if (limit < 0)
> +	err = readl_poll_timeout(ioaddr + PTP_TCR, value,
> +				 !(value & PTP_TCR_TSINIT),
> +				 10000, 100000);
> +	if (err)
>  		return -EBUSY;

Hi Dejin

It is normal to just return whatever error code readl_poll_timeout()
returned.

	Andrew