RE: [PATCH v5 08/10] net: eth: altera: add support for ptp and timestamping

[Ooi, Joyce]

> -----Original Message-----
> From: Richard Cochran <richardcochran@xxxxxxxxx>
> Sent: Monday, July 27, 2020 10:29 PM
> To: Ooi, Joyce <joyce.ooi@xxxxxxxxx>
> Cc: Thor Thayer <thor.thayer@xxxxxxxxxxxxxxx>; David S . Miller
> <davem@xxxxxxxxxxxxx>; Jakub Kicinski <kuba@xxxxxxxxxx>;
> netdev@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Dalon Westergreen
> <dalon.westergreen@xxxxxxxxxxxxxxx>; Tan, Ley Foon
> <ley.foon.tan@xxxxxxxxx>; See, Chin Liang <chin.liang.see@xxxxxxxxx>;
> Nguyen, Dinh <dinh.nguyen@xxxxxxxxx>; Westergreen, Dalon
> <dalon.westergreen@xxxxxxxxx>
> Subject: Re: [PATCH v5 08/10] net: eth: altera: add support for ptp and
> timestamping
> 
> On Mon, Jul 27, 2020 at 05:21:55PM +0800, Ooi, Joyce wrote:
> 
> > +/* ioctl to configure timestamping */ static int tse_do_ioctl(struct
> > +net_device *dev, struct ifreq *ifr, int cmd) {
> > +	struct altera_tse_private *priv = netdev_priv(dev);
> > +	struct hwtstamp_config config;
> > +
> > +	if (!netif_running(dev))
> > +		return -EINVAL;
> > +
> > +	if (!priv->has_ptp) {
> > +		netdev_alert(priv->dev, "Timestamping not supported");
> > +		return -EOPNOTSUPP;
> > +	}
> 
> The user might well have a PHY that supports time stamping.  The code must
> pass the ioctl through to the PHY even when !priv->has_ptp.
Ok, I'll remove 'return -EOPNOTSUPP;' to allow those that have PHY with timestamping support to go pass through ioctl.

>
> > +
> > +	if (!dev->phydev)
> > +		return -EINVAL;
> > +
> > +	if (!phy_has_hwtstamp(dev->phydev)) {
> > +		if (cmd == SIOCSHWTSTAMP) {
> > +			if (copy_from_user(&config, ifr->ifr_data,
> > +					   sizeof(struct hwtstamp_config)))
> > +				return -EFAULT;
> > +
> > +			if (config.flags)
> > +				return -EINVAL;
> > +
> > +			switch (config.tx_type) {
> > +			case HWTSTAMP_TX_OFF:
> > +				priv->hwts_tx_en = 0;
> > +				break;
> > +			case HWTSTAMP_TX_ON:
> > +				priv->hwts_tx_en = 1;
> > +				break;
> > +			default:
> > +				return -ERANGE;
> > +			}
> > +
> > +			switch (config.rx_filter) {
> > +			case HWTSTAMP_FILTER_NONE:
> > +				priv->hwts_rx_en = 0;
> > +				config.rx_filter = HWTSTAMP_FILTER_NONE;
> > +				break;
> > +			default:
> > +				priv->hwts_rx_en = 1;
> > +				config.rx_filter = HWTSTAMP_FILTER_ALL;
> > +				break;
> > +			}
> > +
> > +			if (copy_to_user(ifr->ifr_data, &config,
> > +					 sizeof(struct hwtstamp_config)))
> > +				return -EFAULT;
> > +			else
> > +				return 0;
> > +		}
> > +
> > +		if (cmd == SIOCGHWTSTAMP) {
> > +			config.flags = 0;
> > +
> > +			if (priv->hwts_tx_en)
> > +				config.tx_type = HWTSTAMP_TX_ON;
> > +			else
> > +				config.tx_type = HWTSTAMP_TX_OFF;
> > +
> > +			if (priv->hwts_rx_en)
> > +				config.rx_filter = HWTSTAMP_FILTER_ALL;
> > +			else
> > +				config.rx_filter = HWTSTAMP_FILTER_NONE;
> > +
> > +			if (copy_to_user(ifr->ifr_data, &config,
> > +					 sizeof(struct hwtstamp_config)))
> > +				return -EFAULT;
> > +			else
> > +				return 0;
> > +		}
> > +	}
> > +
> > +	return phy_mii_ioctl(dev->phydev, ifr, cmd); }
> 
> Thanks,
> Richard