tg3: Implement the SIOCGHWTSTAMP ioctl

While we're doing this, fix the error code for SIOCSHWTSTAMP ioctl on
non-timestamping hardware.

Compile-tested only.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

drivers/net/ethernet/broadcom/tg3.c

@@ -13603,14 +13603,13 @@ static void tg3_self_test(struct net_device *dev, struct ethtool_test *etest,
 
 }
 
-static int tg3_hwtstamp_ioctl(struct net_device *dev,
-			      struct ifreq *ifr, int cmd)
+static int tg3_hwtstamp_set(struct net_device *dev, struct ifreq *ifr)
 {
 	struct tg3 *tp = netdev_priv(dev);
 	struct hwtstamp_config stmpconf;
 
 	if (!tg3_flag(tp, PTP_CAPABLE))
-		return -EINVAL;
+		return -EOPNOTSUPP;
 
 	if (copy_from_user(&stmpconf, ifr->ifr_data, sizeof(stmpconf)))
 		return -EFAULT;
@@ -13691,6 +13690,67 @@ static int tg3_hwtstamp_ioctl(struct net_device *dev,
 		-EFAULT : 0;
 }
 
+static int tg3_hwtstamp_get(struct net_device *dev, struct ifreq *ifr)
+{
+	struct tg3 *tp = netdev_priv(dev);
+	struct hwtstamp_config stmpconf;
+
+	if (!tg3_flag(tp, PTP_CAPABLE))
+		return -EOPNOTSUPP;
+
+	stmpconf.flags = 0;
+	stmpconf.tx_type = (tg3_flag(tp, TX_TSTAMP_EN) ?
+			    HWTSTAMP_TX_ON : HWTSTAMP_TX_OFF);
+
+	switch (tp->rxptpctl) {
+	case 0:
+		stmpconf.rx_filter = HWTSTAMP_FILTER_NONE;
+		break;
+	case TG3_RX_PTP_CTL_RX_PTP_V1_EN | TG3_RX_PTP_CTL_ALL_V1_EVENTS:
+		stmpconf.rx_filter = HWTSTAMP_FILTER_PTP_V1_L4_EVENT;
+		break;
+	case TG3_RX_PTP_CTL_RX_PTP_V1_EN | TG3_RX_PTP_CTL_SYNC_EVNT:
+		stmpconf.rx_filter = HWTSTAMP_FILTER_PTP_V1_L4_SYNC;
+		break;
+	case TG3_RX_PTP_CTL_RX_PTP_V1_EN | TG3_RX_PTP_CTL_DELAY_REQ:
+		stmpconf.rx_filter = HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ;
+		break;
+	case TG3_RX_PTP_CTL_RX_PTP_V2_EN | TG3_RX_PTP_CTL_ALL_V2_EVENTS:
+		stmpconf.rx_filter = HWTSTAMP_FILTER_PTP_V2_EVENT;
+		break;
+	case TG3_RX_PTP_CTL_RX_PTP_V2_L2_EN | TG3_RX_PTP_CTL_ALL_V2_EVENTS:
+		stmpconf.rx_filter = HWTSTAMP_FILTER_PTP_V2_L2_EVENT;
+		break;
+	case TG3_RX_PTP_CTL_RX_PTP_V2_L4_EN | TG3_RX_PTP_CTL_ALL_V2_EVENTS:
+		stmpconf.rx_filter = HWTSTAMP_FILTER_PTP_V2_L4_EVENT;
+		break;
+	case TG3_RX_PTP_CTL_RX_PTP_V2_EN | TG3_RX_PTP_CTL_SYNC_EVNT:
+		stmpconf.rx_filter = HWTSTAMP_FILTER_PTP_V2_SYNC;
+		break;
+	case TG3_RX_PTP_CTL_RX_PTP_V2_L2_EN | TG3_RX_PTP_CTL_SYNC_EVNT:
+		stmpconf.rx_filter = HWTSTAMP_FILTER_PTP_V2_L2_SYNC;
+		break;
+	case TG3_RX_PTP_CTL_RX_PTP_V2_L4_EN | TG3_RX_PTP_CTL_SYNC_EVNT:
+		stmpconf.rx_filter = HWTSTAMP_FILTER_PTP_V2_L4_SYNC;
+		break;
+	case TG3_RX_PTP_CTL_RX_PTP_V2_EN | TG3_RX_PTP_CTL_DELAY_REQ:
+		stmpconf.rx_filter = HWTSTAMP_FILTER_PTP_V2_DELAY_REQ;
+		break;
+	case TG3_RX_PTP_CTL_RX_PTP_V2_L2_EN | TG3_RX_PTP_CTL_DELAY_REQ:
+		stmpconf.rx_filter = HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ;
+		break;
+	case TG3_RX_PTP_CTL_RX_PTP_V2_L4_EN | TG3_RX_PTP_CTL_DELAY_REQ:
+		stmpconf.rx_filter = HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ;
+		break;
+	default:
+		WARN_ON_ONCE(1);
+		return -ERANGE;
+	}
+
+	return copy_to_user(ifr->ifr_data, &stmpconf, sizeof(stmpconf)) ?
+		-EFAULT : 0;
+}
+
 static int tg3_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 {
 	struct mii_ioctl_data *data = if_mii(ifr);
@@ -13744,7 +13804,10 @@ static int tg3_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 		return err;
 
 	case SIOCSHWTSTAMP:
-		return tg3_hwtstamp_ioctl(dev, ifr, cmd);
+		return tg3_hwtstamp_set(dev, ifr);
+
+	case SIOCGHWTSTAMP:
+		return tg3_hwtstamp_get(dev, ifr);
 
 	default:
 		/* do nothing */