[PATCH net-next 0/5] dp83640 driver fixes

[PATCH net-next 0/5] dp83640 driver fixes

[Stefan Sørensen]

This series fixes a number of minor bugs in the dp83640 driver. 

Stefan Sørensen (5):
  dp83640: Include hash in timestamp/packet matching
  dp83640: Delay scheduled work.
  dp83640: Prune rx timestamp list before reading from it
  ptp: Change ptp_class to a proper bitmask
  dp83640: Only wait for timestamps for packets with timestamping enabled.

 drivers/net/phy/dp83640.c    | 60 +++++++++++++++++++++++++++-----------------
 include/linux/ptp_classify.h |  7 +++---
 net/core/ptp_classifier.c    | 16 ++++++------
 3 files changed, 49 insertions(+), 34 deletions(-)

-- 
2.5.0

[PATCH net-next 1/5] dp83640: Include hash in timestamp/packet matching

[Stefan Sørensen]

Only using the message type and sequence id for matching timestamps with
packets is error prone, particularly if packets can be reordered. Fix by
extending the check to include the hash of bytes 20-29 (source id in PTPv2)
that is provided with the timestamps.

Signed-off-by: Stefan Sørensen <stefan.sorensen@spectralink.com>
---
 drivers/net/phy/dp83640.c | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/drivers/net/phy/dp83640.c b/drivers/net/phy/dp83640.c
index 185b03c..9534478 100644
--- a/drivers/net/phy/dp83640.c
+++ b/drivers/net/phy/dp83640.c
@@ -20,6 +20,7 @@
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
+#include <linux/crc32.h>
 #include <linux/ethtool.h>
 #include <linux/kernel.h>
 #include <linux/list.h>
@@ -789,7 +790,7 @@ static int decode_evnt(struct dp83640_private *dp83640,
 
 static int match(struct sk_buff *skb, unsigned int type, struct rxts *rxts)
 {
-	u16 *seqid;
+	u16 *seqid, hash;
 	unsigned int offset = 0;
 	u8 *msgtype, *data = skb_mac_header(skb);
 
@@ -819,11 +820,18 @@ static int match(struct sk_buff *skb, unsigned int type, struct rxts *rxts)
 		msgtype = data + offset + OFF_PTP_CONTROL;
 	else
 		msgtype = data + offset;
+	if (rxts->msgtype != (*msgtype & 0xf))
+		return 0;
 
 	seqid = (u16 *)(data + offset + OFF_PTP_SEQUENCE_ID);
+	if (rxts->seqid != ntohs(*seqid))
+		return 0;
+
+	hash = ether_crc(10, data + offset + 20) >> 20;
+	if (rxts->hash != hash)
+		return 0;
 
-	return rxts->msgtype == (*msgtype & 0xf) &&
-		rxts->seqid   == ntohs(*seqid);
+	return 1;
 }
 
 static void decode_rxts(struct dp83640_private *dp83640,
-- 
2.5.0

[PATCH net-next 2/5] dp83640: Delay scheduled work.

[Stefan Sørensen]

Currently rx_timestamp_work reschedules itself as a regular workqueue item,
effectively causing it run constantly as long as there are packets left in
the queue. Fix by using delayed workqueue items, limiting it to run only
every two jiffies.

Signed-off-by: Stefan Sørensen <stefan.sorensen@spectralink.com>
---
 drivers/net/phy/dp83640.c | 20 ++++++++++++--------
 1 file changed, 12 insertions(+), 8 deletions(-)

diff --git a/drivers/net/phy/dp83640.c b/drivers/net/phy/dp83640.c
index 9534478..f3e812b 100644
--- a/drivers/net/phy/dp83640.c
+++ b/drivers/net/phy/dp83640.c
@@ -69,6 +69,8 @@
 /* phyter seems to miss the mark by 16 ns */
 #define ADJTIME_FIX	16
 
+#define SKB_TIMESTAMP_TIMEOUT	2 /* jiffies */
+
 #if defined(__BIG_ENDIAN)
 #define ENDIAN_FLAG	0
 #elif defined(__LITTLE_ENDIAN)
@@ -111,7 +113,7 @@ struct dp83640_private {
 	struct list_head list;
 	struct dp83640_clock *clock;
 	struct phy_device *phydev;
-	struct work_struct ts_work;
+	struct delayed_work ts_work;
 	int hwts_tx_en;
 	int hwts_rx_en;
 	int layer;
@@ -285,7 +287,7 @@ static void phy2rxts(struct phy_rxts *p, struct rxts *rxts)
 	rxts->seqid = p->seqid;
 	rxts->msgtype = (p->msgtype >> 12) & 0xf;
 	rxts->hash = p->msgtype & 0x0fff;
-	rxts->tmo = jiffies + 2;
+	rxts->tmo = jiffies + SKB_TIMESTAMP_TIMEOUT;
 }
 
 static u64 phy2txts(struct phy_txts *p)
@@ -1111,7 +1113,7 @@ static int dp83640_probe(struct phy_device *phydev)
 		goto no_memory;
 
 	dp83640->phydev = phydev;
-	INIT_WORK(&dp83640->ts_work, rx_timestamp_work);
+	INIT_DELAYED_WORK(&dp83640->ts_work, rx_timestamp_work);
 
 	INIT_LIST_HEAD(&dp83640->rxts);
 	INIT_LIST_HEAD(&dp83640->rxpool);
@@ -1158,7 +1160,7 @@ static void dp83640_remove(struct phy_device *phydev)
 		return;
 
 	enable_status_frames(phydev, false);
-	cancel_work_sync(&dp83640->ts_work);
+	cancel_delayed_work_sync(&dp83640->ts_work);
 
 	skb_queue_purge(&dp83640->rx_queue);
 	skb_queue_purge(&dp83640->tx_queue);
@@ -1352,7 +1354,7 @@ static int dp83640_hwtstamp(struct phy_device *phydev, struct ifreq *ifr)
 static void rx_timestamp_work(struct work_struct *work)
 {
 	struct dp83640_private *dp83640 =
-		container_of(work, struct dp83640_private, ts_work);
+		container_of(work, struct dp83640_private, ts_work.work);
 	struct sk_buff *skb;
 
 	/* Deliver expired packets. */
@@ -1369,7 +1371,7 @@ static void rx_timestamp_work(struct work_struct *work)
 	}
 
 	if (!skb_queue_empty(&dp83640->rx_queue))
-		schedule_work(&dp83640->ts_work);
+		schedule_delayed_work(&dp83640->ts_work, SKB_TIMESTAMP_TIMEOUT);
 }
 
 static bool dp83640_rxtstamp(struct phy_device *phydev,
@@ -1408,9 +1410,11 @@ static bool dp83640_rxtstamp(struct phy_device *phydev,
 
 	if (!shhwtstamps) {
 		skb_info->ptp_type = type;
-		skb_info->tmo = jiffies + 2;
+		skb_info->tmo = jiffies + SKB_TIMESTAMP_TIMEOUT;
 		skb_queue_tail(&dp83640->rx_queue, skb);
-		schedule_work(&dp83640->ts_work);
+		schedule_delayed_work(&dp83640->ts_work, SKB_TIMESTAMP_TIMEOUT);
+	} else {
+		netif_rx_ni(skb);
 	}
 
 	return true;
-- 
2.5.0

[PATCH net-next 3/5] dp83640: Prune rx timestamp list before reading from it

[Stefan Sørensen]

The list of rx timestamps are currently only pruned of old entries when a
new entry is inserted. If no new entries are added, old timestamps may
survive beyond their lifetime, possible causing them to be attached to
packets with the same sequence number after a rollover.

Signed-off-by: Stefan Sørensen <stefan.sorensen@spectralink.com>
---
 drivers/net/phy/dp83640.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/net/phy/dp83640.c b/drivers/net/phy/dp83640.c
index f3e812b..c1f70b7 100644
--- a/drivers/net/phy/dp83640.c
+++ b/drivers/net/phy/dp83640.c
@@ -1394,6 +1394,7 @@ static bool dp83640_rxtstamp(struct phy_device *phydev,
 		return false;
 
 	spin_lock_irqsave(&dp83640->rx_lock, flags);
+	prune_rx_ts(dp83640);
 	list_for_each_safe(this, next, &dp83640->rxts) {
 		rxts = list_entry(this, struct rxts, list);
 		if (match(skb, type, rxts)) {
-- 
2.5.0

[PATCH net-next 4/5] ptp: Change ptp_class to a proper bitmask

[Stefan Sørensen]

Change the definition of PTP_CLASS_L2 to not have any bits overlapping with
the other defined protocol values, allowing the PTP_CLASS_* definitions to
be for simple filtering on packet type.

Signed-off-by: Stefan Sørensen <stefan.sorensen@spectralink.com>
---
 include/linux/ptp_classify.h |  7 ++++---
 net/core/ptp_classifier.c    | 16 ++++++++--------
 2 files changed, 12 insertions(+), 11 deletions(-)

diff --git a/include/linux/ptp_classify.h b/include/linux/ptp_classify.h
index 159c987..a079656 100644
--- a/include/linux/ptp_classify.h
+++ b/include/linux/ptp_classify.h
@@ -32,9 +32,9 @@
 #define PTP_CLASS_VMASK 0x0f /* max protocol version is 15 */
 #define PTP_CLASS_IPV4  0x10 /* event in an IPV4 UDP packet */
 #define PTP_CLASS_IPV6  0x20 /* event in an IPV6 UDP packet */
-#define PTP_CLASS_L2    0x30 /* event in a L2 packet */
-#define PTP_CLASS_PMASK 0x30 /* mask for the packet type field */
-#define PTP_CLASS_VLAN  0x40 /* event in a VLAN tagged packet */
+#define PTP_CLASS_L2    0x40 /* event in a L2 packet */
+#define PTP_CLASS_PMASK	0x70 /* mask for the packet type field */
+#define PTP_CLASS_VLAN	0x80 /* event in a VLAN tagged packet */
 
 #define PTP_CLASS_V1_IPV4 (PTP_CLASS_V1 | PTP_CLASS_IPV4)
 #define PTP_CLASS_V1_IPV6 (PTP_CLASS_V1 | PTP_CLASS_IPV6) /* probably DNE */
@@ -42,6 +42,7 @@
 #define PTP_CLASS_V2_IPV6 (PTP_CLASS_V2 | PTP_CLASS_IPV6)
 #define PTP_CLASS_V2_L2   (PTP_CLASS_V2 | PTP_CLASS_L2)
 #define PTP_CLASS_V2_VLAN (PTP_CLASS_V2 | PTP_CLASS_VLAN)
+#define PTP_CLASS_L4      (PTP_CLASS_IPV4 | PTP_CLASS_IPV6)
 
 #define PTP_EV_PORT 319
 #define PTP_GEN_BIT 0x08 /* indicates general message, if set in message type */
diff --git a/net/core/ptp_classifier.c b/net/core/ptp_classifier.c
index 4eab4a9..703cf76 100644
--- a/net/core/ptp_classifier.c
+++ b/net/core/ptp_classifier.c
@@ -58,7 +58,7 @@
  *   jneq #0x0, drop_ieee1588      ; for PTP_GEN_BIT and drop these
  *   ldh [18]                      ; reload payload
  *   and #0xf                      ; mask PTP_CLASS_VMASK
- *   or #0x70                      ; PTP_CLASS_VLAN|PTP_CLASS_L2
+ *   or #0xc0                      ; PTP_CLASS_VLAN|PTP_CLASS_L2
  *   ret a                         ; return PTP class
  *
  * ; PTP over UDP over IPv4 over 802.1Q over Ethernet
@@ -73,7 +73,7 @@
  *   jneq #319, drop_8021q_ipv4    ; is port PTP_EV_PORT ?
  *   ldh [x + 26]                  ; load payload
  *   and #0xf                      ; mask PTP_CLASS_VMASK
- *   or #0x50                      ; PTP_CLASS_VLAN|PTP_CLASS_IPV4
+ *   or #0x90                      ; PTP_CLASS_VLAN|PTP_CLASS_IPV4
  *   ret a                         ; return PTP class
  *   drop_8021q_ipv4: ret #0x0     ; PTP_CLASS_NONE
  *
@@ -86,7 +86,7 @@
  *   jneq #319, drop_8021q_ipv6          ; is port PTP_EV_PORT ?
  *   ldh [66]                      ; load payload
  *   and #0xf                      ; mask PTP_CLASS_VMASK
- *   or #0x60                      ; PTP_CLASS_VLAN|PTP_CLASS_IPV6
+ *   or #0xa0                      ; PTP_CLASS_VLAN|PTP_CLASS_IPV6
  *   ret a                         ; return PTP class
  *   drop_8021q_ipv6: ret #0x0     ; PTP_CLASS_NONE
  *
@@ -98,7 +98,7 @@
  *   jneq #0x0, drop_ieee1588      ; for PTP_GEN_BIT and drop these
  *   ldh [14]                      ; reload payload
  *   and #0xf                      ; mask PTP_CLASS_VMASK
- *   or #0x30                      ; PTP_CLASS_L2
+ *   or #0x40                      ; PTP_CLASS_L2
  *   ret a                         ; return PTP class
  *   drop_ieee1588: ret #0x0       ; PTP_CLASS_NONE
  */
@@ -150,7 +150,7 @@ void __init ptp_classifier_init(void)
 		{ 0x15,  0, 35, 0x00000000 },
 		{ 0x28,  0,  0, 0x00000012 },
 		{ 0x54,  0,  0, 0x0000000f },
-		{ 0x44,  0,  0, 0x00000070 },
+		{ 0x44,  0,  0, 0x000000c0 },
 		{ 0x16,  0,  0, 0x00000000 },
 		{ 0x15,  0, 12, 0x00000800 },
 		{ 0x30,  0,  0, 0x0000001b },
@@ -162,7 +162,7 @@ void __init ptp_classifier_init(void)
 		{ 0x15,  0,  4, 0x0000013f },
 		{ 0x48,  0,  0, 0x0000001a },
 		{ 0x54,  0,  0, 0x0000000f },
-		{ 0x44,  0,  0, 0x00000050 },
+		{ 0x44,  0,  0, 0x00000090 },
 		{ 0x16,  0,  0, 0x00000000 },
 		{ 0x06,  0,  0, 0x00000000 },
 		{ 0x15,  0,  8, 0x000086dd },
@@ -172,7 +172,7 @@ void __init ptp_classifier_init(void)
 		{ 0x15,  0,  4, 0x0000013f },
 		{ 0x28,  0,  0, 0x00000042 },
 		{ 0x54,  0,  0, 0x0000000f },
-		{ 0x44,  0,  0, 0x00000060 },
+		{ 0x44,  0,  0, 0x000000a0 },
 		{ 0x16,  0,  0, 0x00000000 },
 		{ 0x06,  0,  0, 0x00000000 },
 		{ 0x15,  0,  7, 0x000088f7 },
@@ -181,7 +181,7 @@ void __init ptp_classifier_init(void)
 		{ 0x15,  0,  4, 0x00000000 },
 		{ 0x28,  0,  0, 0x0000000e },
 		{ 0x54,  0,  0, 0x0000000f },
-		{ 0x44,  0,  0, 0x00000030 },
+		{ 0x44,  0,  0, 0x00000040 },
 		{ 0x16,  0,  0, 0x00000000 },
 		{ 0x06,  0,  0, 0x00000000 },
 	};
-- 
2.5.0

[PATCH net-next 5/5] dp83640: Only wait for timestamps for packets with timestamping enabled.

[Stefan Sørensen]

In the packet timestamping function, check that the ptp version and
protocol of the packet matches what we have configured the hardware to
actually generate timestamps for, before looking/waiting for a timestamp.

Signed-off-by: Stefan Sørensen <stefan.sorensen@spectralink.com>
---
 drivers/net/phy/dp83640.c | 25 +++++++++++++------------
 1 file changed, 13 insertions(+), 12 deletions(-)

diff --git a/drivers/net/phy/dp83640.c b/drivers/net/phy/dp83640.c
index c1f70b7..30bfeb1 100644
--- a/drivers/net/phy/dp83640.c
+++ b/drivers/net/phy/dp83640.c
@@ -37,8 +37,6 @@
 
 #define DP83640_PHY_ID	0x20005ce1
 #define PAGESEL		0x13
-#define LAYER4		0x02
-#define LAYER2		0x01
 #define MAX_RXTS	64
 #define N_EXT_TS	6
 #define N_PER_OUT	7
@@ -1292,29 +1290,29 @@ static int dp83640_hwtstamp(struct phy_device *phydev, struct ifreq *ifr)
 	case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
 	case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
 		dp83640->hwts_rx_en = 1;
-		dp83640->layer = LAYER4;
-		dp83640->version = 1;
+		dp83640->layer = PTP_CLASS_L4;
+		dp83640->version = PTP_CLASS_V1;
 		break;
 	case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
 	case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
 	case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ:
 		dp83640->hwts_rx_en = 1;
-		dp83640->layer = LAYER4;
-		dp83640->version = 2;
+		dp83640->layer = PTP_CLASS_L4;
+		dp83640->version = PTP_CLASS_V2;
 		break;
 	case HWTSTAMP_FILTER_PTP_V2_L2_EVENT:
 	case HWTSTAMP_FILTER_PTP_V2_L2_SYNC:
 	case HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ:
 		dp83640->hwts_rx_en = 1;
-		dp83640->layer = LAYER2;
-		dp83640->version = 2;
+		dp83640->layer = PTP_CLASS_L2;
+		dp83640->version = PTP_CLASS_V2;
 		break;
 	case HWTSTAMP_FILTER_PTP_V2_EVENT:
 	case HWTSTAMP_FILTER_PTP_V2_SYNC:
 	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
 		dp83640->hwts_rx_en = 1;
-		dp83640->layer = LAYER4|LAYER2;
-		dp83640->version = 2;
+		dp83640->layer = PTP_CLASS_L4 | PTP_CLASS_L2;
+		dp83640->version = PTP_CLASS_V2;
 		break;
 	default:
 		return -ERANGE;
@@ -1323,11 +1321,11 @@ static int dp83640_hwtstamp(struct phy_device *phydev, struct ifreq *ifr)
 	txcfg0 = (dp83640->version & TX_PTP_VER_MASK) << TX_PTP_VER_SHIFT;
 	rxcfg0 = (dp83640->version & TX_PTP_VER_MASK) << TX_PTP_VER_SHIFT;
 
-	if (dp83640->layer & LAYER2) {
+	if (dp83640->layer & PTP_CLASS_L2) {
 		txcfg0 |= TX_L2_EN;
 		rxcfg0 |= RX_L2_EN;
 	}
-	if (dp83640->layer & LAYER4) {
+	if (dp83640->layer & PTP_CLASS_L4) {
 		txcfg0 |= TX_IPV6_EN | TX_IPV4_EN;
 		rxcfg0 |= RX_IPV6_EN | RX_IPV4_EN;
 	}
@@ -1393,6 +1391,9 @@ static bool dp83640_rxtstamp(struct phy_device *phydev,
 	if (!dp83640->hwts_rx_en)
 		return false;
 
+	if ((type & dp83640->version) == 0 || (type & dp83640->layer) == 0)
+		return false;
+
 	spin_lock_irqsave(&dp83640->rx_lock, flags);
 	prune_rx_ts(dp83640);
 	list_for_each_safe(this, next, &dp83640->rxts) {
-- 
2.5.0

Re: [PATCH net-next 1/5] dp83640: Include hash in timestamp/packet matching

[Richard Cochran]

On Fri, Oct 30, 2015 at 01:14:00PM +0100, Stefan Sørensen wrote:
> Only using the message type and sequence id for matching timestamps with
> packets is error prone, particularly if packets can be reordered. Fix by
> extending the check to include the hash of bytes 20-29 (source id in PTPv2)
> that is provided with the timestamps.

The example of reordered packets is bogus, since the sequence numbers
are not affected.  The one case that benefits from the hash check is
when the port is in the master role and multiple clients send
Delay_Req messages all with the same sequence number by chance.
 
> @@ -819,11 +820,18 @@ static int match(struct sk_buff *skb, unsigned int type, struct rxts *rxts)
>  		msgtype = data + offset + OFF_PTP_CONTROL;
>  	else
>  		msgtype = data + offset;
> +	if (rxts->msgtype != (*msgtype & 0xf))
> +		return 0;
>  
>  	seqid = (u16 *)(data + offset + OFF_PTP_SEQUENCE_ID);
> +	if (rxts->seqid != ntohs(*seqid))
> +		return 0;
> +
> +	hash = ether_crc(10, data + offset + 20) >> 20;

This could use a macro instead of magic 20.

Thanks,
Richard

> +	if (rxts->hash != hash)
> +		return 0;
>  
> -	return rxts->msgtype == (*msgtype & 0xf) &&
> -		rxts->seqid   == ntohs(*seqid);
> +	return 1;
>  }
>  
>  static void decode_rxts(struct dp83640_private *dp83640,
> -- 
> 2.5.0
> 

Re: [PATCH net-next 2/5] dp83640: Delay scheduled work.

[Richard Cochran]

On Fri, Oct 30, 2015 at 01:14:01PM +0100, Stefan Sørensen wrote:
> Currently rx_timestamp_work reschedules itself as a regular workqueue item,
> effectively causing it run constantly as long as there are packets left in
> the queue. Fix by using delayed workqueue items, limiting it to run only
> every two jiffies.

NAK.  We want to have the time stamp ASAP, because the delay between
the transmission of the Sync and its application in the servo degrades
or even spoils synchronization.  Think of an ARM SoC with HZ=100.  Two
jiffies are 20 milliseconds.

Thanks,
Richard

Re: [PATCH net-next 3/5] dp83640: Prune rx timestamp list before reading from it

[Richard Cochran]

On Fri, Oct 30, 2015 at 01:14:02PM +0100, Stefan Sørensen wrote:
> The list of rx timestamps are currently only pruned of old entries when a
> new entry is inserted. If no new entries are added, old timestamps may
> survive beyond their lifetime, possible causing them to be attached to
> packets with the same sequence number after a rollover.
> 
> Signed-off-by: Stefan Sørensen <stefan.sorensen@spectralink.com>

Acked-by: Richard Cochran <richardcochran@gmail.com>

Re: [PATCH net-next 4/5] ptp: Change ptp_class to a proper bitmask

[Richard Cochran]

On Fri, Oct 30, 2015 at 01:14:03PM +0100, Stefan Sørensen wrote:
> Change the definition of PTP_CLASS_L2 to not have any bits overlapping with
> the other defined protocol values, allowing the PTP_CLASS_* definitions to
> be for simple filtering on packet type.
> 
> Signed-off-by: Stefan Sørensen <stefan.sorensen@spectralink.com>

Acked-by: Richard Cochran <richardcochran@gmail.com>

Re: [PATCH net-next 5/5] dp83640: Only wait for timestamps for packets with timestamping enabled.

[Richard Cochran]

On Fri, Oct 30, 2015 at 01:14:04PM +0100, Stefan Sørensen wrote:
> In the packet timestamping function, check that the ptp version and
> protocol of the packet matches what we have configured the hardware to
> actually generate timestamps for, before looking/waiting for a timestamp.
> 
> Signed-off-by: Stefan Sørensen <stefan.sorensen@spectralink.com>

Acked-by: Richard Cochran <richardcochran@gmail.com>

Re: [PATCH net-next 2/5] dp83640: Delay scheduled work.

[Sørensen, Stefan]

On Fri, 2015-10-30 at 21:37 +0100, Richard Cochran wrote:
> 
> NAK.  We want to have the time stamp ASAP, because the delay between
> the transmission of the Sync and its application in the servo
> degrades or even spoils synchronization.  Think of an ARM SoC with
> HZ=100.  Two jiffies are 20 milliseconds.

The workqueue is only used for delivering packets where the timestamp
was lost - if a timestamp is received, the packet is delivered
immediately. This patch may introduce a slight delay of the packets
where the timestamp never arrives, by these packets are properly not
very useful to the application anyway.

Stefan

Re: [PATCH net-next 2/5] dp83640: Delay scheduled work.

[Richard Cochran]

On Mon, Nov 02, 2015 at 07:23:12AM +0000, Sørensen, Stefan wrote:
> The workqueue is only used for delivering packets where the timestamp
> was lost - if a timestamp is received, the packet is delivered
> immediately. This patch may introduce a slight delay of the packets
> where the timestamp never arrives, by these packets are properly not
> very useful to the application anyway.

Ok, thanks for the explanation.  I mixed this up with another out of
tree driver that I was hacking recently.

Acked-by: Richard Cochran <richardcochran@gmail.com>

Re: [PATCH net-next 0/5] dp83640 driver fixes

[David Miller]

From: Stefan Sørensen <stefan.sorensen@spectralink.com>
Date: Fri, 30 Oct 2015 13:13:59 +0100

> This series fixes a number of minor bugs in the dp83640 driver. 

Looks like Richard wants changes to patch #1.

Re: [PATCH net-next 0/5] dp83640 driver fixes

[Richard Cochran]

On Mon, Nov 02, 2015 at 03:13:16PM -0500, David Miller wrote:
> Looks like Richard wants changes to patch #1.

Yes, please update the description and use a macro for the offset.
Other than that, the series looks ok to me.

Thanks,
Richard