[PATCH 0/6] More preparation for supporting esd CAN-USB/3

[PATCH 0/6] More preparation for supporting esd CAN-USB/3

[Frank Jungclaus]

Hej,

here is a second batch of patches which must also be seen as
preparation for adding support of the newly available esd CAN-USB/3 to
esd_usb.c.

Frank Jungclaus (6):
  can: esd_usb: Allow REC and TEC to return to zero
  can: esd_usb: Improved behavior on esd CAN_ERROR_EXT event (1)
  can: esd_usb: Improved behavior on esd CAN_ERROR_EXT event (2)
  can: esd_usb: Improved behavior on esd CAN_ERROR_EXT event (3)
  can: esd_usb: Improved support for CAN_CTRLMODE_BERR_REPORTING
  can/esd_usb: Improved decoding for ESD_EV_CAN_ERROR_EXT messages

 drivers/net/can/usb/esd_usb.c | 87 +++++++++++++++++++++++++++--------
 1 file changed, 67 insertions(+), 20 deletions(-)


base-commit: 0ebd5529d2ddab76a46681991d350b82c62ef13e
-- 
2.25.1

[PATCH 1/6] can: esd_usb: Allow REC and TEC to return to zero

[Frank Jungclaus]

We don't get any further EVENT from an esd CAN USB device for changes
on REC or TEC while those counters converge to 0 (with ecc == 0).
So when handling the "Back to ACTIVE"-event force txerr =
rxerr = 0, otherwise the berr-counters might stay on values like 95
forever ...

Signed-off-by: Frank Jungclaus <frank.jungclaus@esd.eu>
---
 drivers/net/can/usb/esd_usb.c | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/net/can/usb/esd_usb.c b/drivers/net/can/usb/esd_usb.c
index 8a4bf2961f3d..0b907bc54b70 100644
--- a/drivers/net/can/usb/esd_usb.c
+++ b/drivers/net/can/usb/esd_usb.c
@@ -229,10 +229,14 @@ static void esd_usb_rx_event(struct esd_usb_net_priv *priv,
 
 	if (id == ESD_EV_CAN_ERROR_EXT) {
 		u8 state = msg->msg.rx.data[0];
-		u8 ecc = msg->msg.rx.data[1];
+		u8 ecc   = msg->msg.rx.data[1];
 		u8 rxerr = msg->msg.rx.data[2];
 		u8 txerr = msg->msg.rx.data[3];
 
+		netdev_dbg(priv->netdev,
+			   "CAN_ERR_EV_EXT: dlc=%#02x state=%02x ecc=%02x rec=%02x tec=%02x\n",
+			   msg->msg.rx.dlc, state, ecc, rxerr, txerr);
+
 		skb = alloc_can_err_skb(priv->netdev, &cf);
 		if (skb == NULL) {
 			stats->rx_dropped++;
@@ -259,6 +263,15 @@ static void esd_usb_rx_event(struct esd_usb_net_priv *priv,
 				break;
 			default:
 				priv->can.state = CAN_STATE_ERROR_ACTIVE;
+				/* We don't get any further EVENT for changes on
+				 * REC or TEC while converging to 0, once we are
+				 * back on ACTIVE.
+				 * So force txerr = rxerr = 0, otherwise the
+				 * berr-counters might stay on values like
+				 * 95 forever ...
+				 */
+				txerr = 0;
+				rxerr = 0;
 				break;
 			}
 		} else {
@@ -292,6 +305,7 @@ static void esd_usb_rx_event(struct esd_usb_net_priv *priv,
 					CAN_ERR_CRTL_TX_PASSIVE :
 					CAN_ERR_CRTL_RX_PASSIVE;
 			}
+
 			cf->data[6] = txerr;
 			cf->data[7] = rxerr;
 		}
-- 
2.25.1

[PATCH 2/6] can: esd_usb: Improved behavior on esd CAN_ERROR_EXT event (1)

[Frank Jungclaus]

Always report CAN_ERR_PROT | CAN_ERR_BUSERROR if ESD_EV_CAN_ERROR_EXT
and ecc != 0. Before we missed those EVENTs when state was unequal to
priv->old_state

Signed-off-by: Frank Jungclaus <frank.jungclaus@esd.eu>
---
 drivers/net/can/usb/esd_usb.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/net/can/usb/esd_usb.c b/drivers/net/can/usb/esd_usb.c
index 0b907bc54b70..e14f08d30b0b 100644
--- a/drivers/net/can/usb/esd_usb.c
+++ b/drivers/net/can/usb/esd_usb.c
@@ -274,12 +274,15 @@ static void esd_usb_rx_event(struct esd_usb_net_priv *priv,
 				rxerr = 0;
 				break;
 			}
-		} else {
+		}
+
+		if (ecc) {
 			priv->can.can_stats.bus_error++;
 			stats->rx_errors++;
 
 			cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
 
+			/* Store error in CAN protocol (type) in data[2] */
 			switch (ecc & SJA1000_ECC_MASK) {
 			case SJA1000_ECC_BIT:
 				cf->data[2] |= CAN_ERR_PROT_BIT;
-- 
2.25.1

[PATCH 3/6] can: esd_usb: Improved behavior on esd CAN_ERROR_EXT event (2)

[Frank Jungclaus]

Moved mislocated supply for cf->data[3] (location of CAN error)
outside of the "switch (ecc & SJA1000_ECC_MASK){}"-statement

Signed-off-by: Frank Jungclaus <frank.jungclaus@esd.eu>
---
 drivers/net/can/usb/esd_usb.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/net/can/usb/esd_usb.c b/drivers/net/can/usb/esd_usb.c
index e14f08d30b0b..0a402a23d7ac 100644
--- a/drivers/net/can/usb/esd_usb.c
+++ b/drivers/net/can/usb/esd_usb.c
@@ -294,7 +294,6 @@ static void esd_usb_rx_event(struct esd_usb_net_priv *priv,
 				cf->data[2] |= CAN_ERR_PROT_STUFF;
 				break;
 			default:
-				cf->data[3] = ecc & SJA1000_ECC_SEG;
 				break;
 			}
 
@@ -302,6 +301,9 @@ static void esd_usb_rx_event(struct esd_usb_net_priv *priv,
 			if (!(ecc & SJA1000_ECC_DIR))
 				cf->data[2] |= CAN_ERR_PROT_TX;
 
+			/* Store error in CAN protocol (location) in data[3] */
+			cf->data[3] = ecc & SJA1000_ECC_SEG;
+
 			if (priv->can.state == CAN_STATE_ERROR_WARNING ||
 			    priv->can.state == CAN_STATE_ERROR_PASSIVE) {
 				cf->data[1] = (txerr > rxerr) ?
-- 
2.25.1

[PATCH 4/6] can: esd_usb: Improved behavior on esd CAN_ERROR_EXT event (3)

[Frank Jungclaus]

Started a rework initiated by Vincents remark about "You should not
report the greatest of txerr and rxerr but the one which actually
increased." Now setting CAN_ERR_CRTL_[RT]X_WARNING and
CAN_ERR_CRTL_[RT]X_PASSIVE depending on REC and TEC

Signed-off-by: Frank Jungclaus <frank.jungclaus@esd.eu>
---
 drivers/net/can/usb/esd_usb.c | 16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/drivers/net/can/usb/esd_usb.c b/drivers/net/can/usb/esd_usb.c
index 0a402a23d7ac..588caba1453b 100644
--- a/drivers/net/can/usb/esd_usb.c
+++ b/drivers/net/can/usb/esd_usb.c
@@ -304,11 +304,17 @@ static void esd_usb_rx_event(struct esd_usb_net_priv *priv,
 			/* Store error in CAN protocol (location) in data[3] */
 			cf->data[3] = ecc & SJA1000_ECC_SEG;
 
-			if (priv->can.state == CAN_STATE_ERROR_WARNING ||
-			    priv->can.state == CAN_STATE_ERROR_PASSIVE) {
-				cf->data[1] = (txerr > rxerr) ?
-					CAN_ERR_CRTL_TX_PASSIVE :
-					CAN_ERR_CRTL_RX_PASSIVE;
+			/* Store error status of CAN-controller in data[1] */
+			if (priv->can.state == CAN_STATE_ERROR_WARNING) {
+				if (txerr >= 96)
+					cf->data[1] |= CAN_ERR_CRTL_TX_WARNING;
+				if (rxerr >= 96)
+					cf->data[1] |= CAN_ERR_CRTL_RX_WARNING;
+			} else if (priv->can.state == CAN_STATE_ERROR_PASSIVE) {
+				if (txerr >= 128)
+					cf->data[1] |= CAN_ERR_CRTL_TX_PASSIVE;
+				if (rxerr >= 128)
+					cf->data[1] |= CAN_ERR_CRTL_RX_PASSIVE;
 			}
 
 			cf->data[6] = txerr;
-- 
2.25.1

[PATCH 5/6] can: esd_usb: Improved support for CAN_CTRLMODE_BERR_REPORTING

[Frank Jungclaus]

Bus error reporting has already been implemented for a long time, but
before it was always active! Now it's user controllable by means off the
"berr-reporting" parameter given to "ip link set ... ", which sets
CAN_CTRLMODE_BERR_REPORTING within priv->can.ctrlmode.

In case of an ESD_EV_CAN_ERROR_EXT now unconditionally supply
priv->bec.rxerr and priv->bec.txerr with REC and TEC.

Signed-off-by: Frank Jungclaus <frank.jungclaus@esd.eu>
---
 drivers/net/can/usb/esd_usb.c | 47 ++++++++++++++++++++---------------
 1 file changed, 27 insertions(+), 20 deletions(-)

diff --git a/drivers/net/can/usb/esd_usb.c b/drivers/net/can/usb/esd_usb.c
index 588caba1453b..09649a45d6ff 100644
--- a/drivers/net/can/usb/esd_usb.c
+++ b/drivers/net/can/usb/esd_usb.c
@@ -230,12 +230,23 @@ static void esd_usb_rx_event(struct esd_usb_net_priv *priv,
 	if (id == ESD_EV_CAN_ERROR_EXT) {
 		u8 state = msg->msg.rx.data[0];
 		u8 ecc   = msg->msg.rx.data[1];
-		u8 rxerr = msg->msg.rx.data[2];
-		u8 txerr = msg->msg.rx.data[3];
+
+		priv->bec.rxerr = msg->msg.rx.data[2];
+		priv->bec.txerr = msg->msg.rx.data[3];
 
 		netdev_dbg(priv->netdev,
 			   "CAN_ERR_EV_EXT: dlc=%#02x state=%02x ecc=%02x rec=%02x tec=%02x\n",
-			   msg->msg.rx.dlc, state, ecc, rxerr, txerr);
+			   msg->msg.rx.dlc, state, ecc, priv->bec.rxerr, priv->bec.txerr);
+
+		if (ecc) {
+			priv->can.can_stats.bus_error++;
+			stats->rx_errors++;
+		}
+
+		if (state == priv->old_state &&
+		    !(priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING))
+			/* Neither a state change nor active bus error reporting */
+			return;
 
 		skb = alloc_can_err_skb(priv->netdev, &cf);
 		if (skb == NULL) {
@@ -270,16 +281,14 @@ static void esd_usb_rx_event(struct esd_usb_net_priv *priv,
 				 * berr-counters might stay on values like
 				 * 95 forever ...
 				 */
-				txerr = 0;
-				rxerr = 0;
+				priv->bec.txerr = 0;
+				priv->bec.rxerr = 0;
 				break;
 			}
 		}
 
-		if (ecc) {
-			priv->can.can_stats.bus_error++;
-			stats->rx_errors++;
-
+		if (ecc && (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)) {
+			/* Only if bus error reporting is active ... */
 			cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
 
 			/* Store error in CAN protocol (type) in data[2] */
@@ -301,29 +310,26 @@ static void esd_usb_rx_event(struct esd_usb_net_priv *priv,
 			if (!(ecc & SJA1000_ECC_DIR))
 				cf->data[2] |= CAN_ERR_PROT_TX;
 
-			/* Store error in CAN protocol (location) in data[3] */
+			/* Store error position in the bit stream of the CAN frame in data[3] */
 			cf->data[3] = ecc & SJA1000_ECC_SEG;
 
 			/* Store error status of CAN-controller in data[1] */
 			if (priv->can.state == CAN_STATE_ERROR_WARNING) {
-				if (txerr >= 96)
+				if (priv->bec.txerr >= 96)
 					cf->data[1] |= CAN_ERR_CRTL_TX_WARNING;
-				if (rxerr >= 96)
+				if (priv->bec.rxerr >= 96)
 					cf->data[1] |= CAN_ERR_CRTL_RX_WARNING;
 			} else if (priv->can.state == CAN_STATE_ERROR_PASSIVE) {
-				if (txerr >= 128)
+				if (priv->bec.txerr >= 128)
 					cf->data[1] |= CAN_ERR_CRTL_TX_PASSIVE;
-				if (rxerr >= 128)
+				if (priv->bec.rxerr >= 128)
 					cf->data[1] |= CAN_ERR_CRTL_RX_PASSIVE;
 			}
 
-			cf->data[6] = txerr;
-			cf->data[7] = rxerr;
+			cf->data[6] = priv->bec.txerr;
+			cf->data[7] = priv->bec.rxerr;
 		}
 
-		priv->bec.txerr = txerr;
-		priv->bec.rxerr = rxerr;
-
 		netif_rx(skb);
 	}
 }
@@ -1021,7 +1027,8 @@ static int esd_usb_probe_one_net(struct usb_interface *intf, int index)
 
 	priv->can.state = CAN_STATE_STOPPED;
 	priv->can.ctrlmode_supported = CAN_CTRLMODE_LISTENONLY |
-		CAN_CTRLMODE_CC_LEN8_DLC;
+				       CAN_CTRLMODE_CC_LEN8_DLC |
+				       CAN_CTRLMODE_BERR_REPORTING;
 
 	if (le16_to_cpu(dev->udev->descriptor.idProduct) ==
 	    USB_CANUSBM_PRODUCT_ID)
-- 
2.25.1

[PATCH 6/6] can: esd_usb: Improved decoding for ESD_EV_CAN_ERROR_EXT messages

[Frank Jungclaus]

As suggested by Vincent I spend a union plus a struct ev_can_err_ext
for easier decoding of an ESD_EV_CAN_ERROR_EXT event message (which
simply is a rx_msg with some dedicated data).

Signed-off-by: Frank Jungclaus <frank.jungclaus@esd.eu>
---
 drivers/net/can/usb/esd_usb.c | 20 ++++++++++++++------
 1 file changed, 14 insertions(+), 6 deletions(-)

diff --git a/drivers/net/can/usb/esd_usb.c b/drivers/net/can/usb/esd_usb.c
index 09649a45d6ff..2b149590720c 100644
--- a/drivers/net/can/usb/esd_usb.c
+++ b/drivers/net/can/usb/esd_usb.c
@@ -126,7 +126,15 @@ struct rx_msg {
 	u8 dlc;
 	__le32 ts;
 	__le32 id; /* upper 3 bits contain flags */
-	u8 data[8];
+	union {
+		u8 data[8];
+		struct {
+			u8 status; /* CAN Controller Status */
+			u8 ecc;    /* Error Capture Register */
+			u8 rec;    /* RX Error Counter */
+			u8 tec;    /* TX Error Counter */
+		} ev_can_err_ext;  /* For ESD_EV_CAN_ERROR_EXT */
+	};
 };
 
 struct tx_msg {
@@ -134,7 +142,7 @@ struct tx_msg {
 	u8 cmd;
 	u8 net;
 	u8 dlc;
-	u32 hnd;	/* opaque handle, not used by device */
+	u32 hnd;   /* opaque handle, not used by device */
 	__le32 id; /* upper 3 bits contain flags */
 	u8 data[8];
 };
@@ -228,11 +236,11 @@ static void esd_usb_rx_event(struct esd_usb_net_priv *priv,
 	u32 id = le32_to_cpu(msg->msg.rx.id) & ESD_IDMASK;
 
 	if (id == ESD_EV_CAN_ERROR_EXT) {
-		u8 state = msg->msg.rx.data[0];
-		u8 ecc   = msg->msg.rx.data[1];
+		u8 state = msg->msg.rx.ev_can_err_ext.status;
+		u8 ecc   = msg->msg.rx.ev_can_err_ext.ecc;
 
-		priv->bec.rxerr = msg->msg.rx.data[2];
-		priv->bec.txerr = msg->msg.rx.data[3];
+		priv->bec.rxerr = msg->msg.rx.ev_can_err_ext.rec;
+		priv->bec.txerr = msg->msg.rx.ev_can_err_ext.tec;
 
 		netdev_dbg(priv->netdev,
 			   "CAN_ERR_EV_EXT: dlc=%#02x state=%02x ecc=%02x rec=%02x tec=%02x\n",
-- 
2.25.1

Re: [PATCH 6/6] can: esd_usb: Improved decoding for ESD_EV_CAN_ERROR_EXT messages

[Vincent MAILHOL]

On Sat. 9 Jul. 2022 at 03:14, Frank Jungclaus <frank.jungclaus@esd.eu> wrote:
> As suggested by Vincent I spend a union plus a struct ev_can_err_ext

The canonical way to declare that something was suggested by someone
else is to use the Suggested-by tag.

Also, this particular change was suggested by Marc, not by me ;)
https://lore.kernel.org/linux-can/20220621071152.ggyhrr5sbzvwpkpx@pengutronix.de/

> for easier decoding of an ESD_EV_CAN_ERROR_EXT event message (which
> simply is a rx_msg with some dedicated data).

Suggested-by: Marc Kleine-Budde <mkl@pengutronix.de>

> Signed-off-by: Frank Jungclaus <frank.jungclaus@esd.eu>
> ---
>  drivers/net/can/usb/esd_usb.c | 20 ++++++++++++++------
>  1 file changed, 14 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/net/can/usb/esd_usb.c b/drivers/net/can/usb/esd_usb.c
> index 09649a45d6ff..2b149590720c 100644
> --- a/drivers/net/can/usb/esd_usb.c
> +++ b/drivers/net/can/usb/esd_usb.c
> @@ -126,7 +126,15 @@ struct rx_msg {
>         u8 dlc;
>         __le32 ts;
>         __le32 id; /* upper 3 bits contain flags */
> -       u8 data[8];
> +       union {
> +               u8 data[8];
> +               struct {
> +                       u8 status; /* CAN Controller Status */
> +                       u8 ecc;    /* Error Capture Register */
> +                       u8 rec;    /* RX Error Counter */
> +                       u8 tec;    /* TX Error Counter */
> +               } ev_can_err_ext;  /* For ESD_EV_CAN_ERROR_EXT */
> +       };
>  };
>
>  struct tx_msg {
> @@ -134,7 +142,7 @@ struct tx_msg {
>         u8 cmd;
>         u8 net;
>         u8 dlc;
> -       u32 hnd;        /* opaque handle, not used by device */
> +       u32 hnd;   /* opaque handle, not used by device */
>         __le32 id; /* upper 3 bits contain flags */
>         u8 data[8];
>  };
> @@ -228,11 +236,11 @@ static void esd_usb_rx_event(struct esd_usb_net_priv *priv,
>         u32 id = le32_to_cpu(msg->msg.rx.id) & ESD_IDMASK;
>
>         if (id == ESD_EV_CAN_ERROR_EXT) {
> -               u8 state = msg->msg.rx.data[0];
> -               u8 ecc   = msg->msg.rx.data[1];
> +               u8 state = msg->msg.rx.ev_can_err_ext.status;
> +               u8 ecc   = msg->msg.rx.ev_can_err_ext.ecc;
>
> -               priv->bec.rxerr = msg->msg.rx.data[2];
> -               priv->bec.txerr = msg->msg.rx.data[3];
> +               priv->bec.rxerr = msg->msg.rx.ev_can_err_ext.rec;
> +               priv->bec.txerr = msg->msg.rx.ev_can_err_ext.tec;
>
>                 netdev_dbg(priv->netdev,
>                            "CAN_ERR_EV_EXT: dlc=%#02x state=%02x ecc=%02x rec=%02x tec=%02x\n",

Yours sincerely,
Vincent Mailhol

Re: [PATCH 5/6] can: esd_usb: Improved support for CAN_CTRLMODE_BERR_REPORTING

[Vincent MAILHOL]

Le sam. 9 juil. 2022 à 03:14, Frank Jungclaus <frank.jungclaus@esd.eu> a écrit :
>
> Bus error reporting has already been implemented for a long time, but
> before it was always active! Now it's user controllable by means off the
> "berr-reporting" parameter given to "ip link set ... ", which sets
> CAN_CTRLMODE_BERR_REPORTING within priv->can.ctrlmode.
>
> In case of an ESD_EV_CAN_ERROR_EXT now unconditionally supply
> priv->bec.rxerr and priv->bec.txerr with REC and TEC.
>
> Signed-off-by: Frank Jungclaus <frank.jungclaus@esd.eu>
> ---
>  drivers/net/can/usb/esd_usb.c | 47 ++++++++++++++++++++---------------
>  1 file changed, 27 insertions(+), 20 deletions(-)
>
> diff --git a/drivers/net/can/usb/esd_usb.c b/drivers/net/can/usb/esd_usb.c
> index 588caba1453b..09649a45d6ff 100644
> --- a/drivers/net/can/usb/esd_usb.c
> +++ b/drivers/net/can/usb/esd_usb.c
> @@ -230,12 +230,23 @@ static void esd_usb_rx_event(struct esd_usb_net_priv *priv,
>         if (id == ESD_EV_CAN_ERROR_EXT) {
>                 u8 state = msg->msg.rx.data[0];
>                 u8 ecc   = msg->msg.rx.data[1];
> -               u8 rxerr = msg->msg.rx.data[2];
> -               u8 txerr = msg->msg.rx.data[3];
> +
> +               priv->bec.rxerr = msg->msg.rx.data[2];
> +               priv->bec.txerr = msg->msg.rx.data[3];
>
>                 netdev_dbg(priv->netdev,
>                            "CAN_ERR_EV_EXT: dlc=%#02x state=%02x ecc=%02x rec=%02x tec=%02x\n",
> -                          msg->msg.rx.dlc, state, ecc, rxerr, txerr);
> +                          msg->msg.rx.dlc, state, ecc, priv->bec.rxerr, priv->bec.txerr);
> +
> +               if (ecc) {
> +                       priv->can.can_stats.bus_error++;
> +                       stats->rx_errors++;
> +               }
> +
> +               if (state == priv->old_state &&
> +                   !(priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING))
> +                       /* Neither a state change nor active bus error reporting */
> +                       return;
>
>                 skb = alloc_can_err_skb(priv->netdev, &cf);
>                 if (skb == NULL) {
> @@ -270,16 +281,14 @@ static void esd_usb_rx_event(struct esd_usb_net_priv *priv,
>                                  * berr-counters might stay on values like
>                                  * 95 forever ...
>                                  */
> -                               txerr = 0;
> -                               rxerr = 0;
> +                               priv->bec.txerr = 0;
> +                               priv->bec.rxerr = 0;
>                                 break;
>                         }
>                 }
>
> -               if (ecc) {
> -                       priv->can.can_stats.bus_error++;
> -                       stats->rx_errors++;
> -
> +               if (ecc && (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)) {
> +                       /* Only if bus error reporting is active ... */
>                         cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
>
>                         /* Store error in CAN protocol (type) in data[2] */
> @@ -301,29 +310,26 @@ static void esd_usb_rx_event(struct esd_usb_net_priv *priv,
>                         if (!(ecc & SJA1000_ECC_DIR))
>                                 cf->data[2] |= CAN_ERR_PROT_TX;
>
> -                       /* Store error in CAN protocol (location) in data[3] */
> +                       /* Store error position in the bit stream of the CAN frame in data[3] */
>                         cf->data[3] = ecc & SJA1000_ECC_SEG;
>
>                         /* Store error status of CAN-controller in data[1] */
>                         if (priv->can.state == CAN_STATE_ERROR_WARNING) {
> -                               if (txerr >= 96)
> +                               if (priv->bec.txerr >= 96)

I checked and was just surprised that we do not have any macro for the
different thresholds.

Does it make sense to add below declarations to include/uapi/linux/can/error.h?

#define CAN_ERROR_WARNING_THRESHOLD 96
#define CAN_ERROR_PASSIVE_THRESHOLD 128

I will try to submit a patch for that by the end of today.

>                                         cf->data[1] |= CAN_ERR_CRTL_TX_WARNING;
> -                               if (rxerr >= 96)
> +                               if (priv->bec.rxerr >= 96)
>                                         cf->data[1] |= CAN_ERR_CRTL_RX_WARNING;
>                         } else if (priv->can.state == CAN_STATE_ERROR_PASSIVE) {
> -                               if (txerr >= 128)
> +                               if (priv->bec.txerr >= 128)
>                                         cf->data[1] |= CAN_ERR_CRTL_TX_PASSIVE;
> -                               if (rxerr >= 128)
> +                               if (priv->bec.rxerr >= 128)
>                                         cf->data[1] |= CAN_ERR_CRTL_RX_PASSIVE;
>                         }
>
> -                       cf->data[6] = txerr;
> -                       cf->data[7] = rxerr;
> +                       cf->data[6] = priv->bec.txerr;
> +                       cf->data[7] = priv->bec.rxerr;
>                 }
>
> -               priv->bec.txerr = txerr;
> -               priv->bec.rxerr = rxerr;
> -
>                 netif_rx(skb);
>         }
>  }
> @@ -1021,7 +1027,8 @@ static int esd_usb_probe_one_net(struct usb_interface *intf, int index)
>
>         priv->can.state = CAN_STATE_STOPPED;
>         priv->can.ctrlmode_supported = CAN_CTRLMODE_LISTENONLY |
> -               CAN_CTRLMODE_CC_LEN8_DLC;
> +                                      CAN_CTRLMODE_CC_LEN8_DLC |
> +                                      CAN_CTRLMODE_BERR_REPORTING;
>
>         if (le16_to_cpu(dev->udev->descriptor.idProduct) ==
>             USB_CANUSBM_PRODUCT_ID)
> --
> 2.25.1
>

Re: [PATCH 4/6] can: esd_usb: Improved behavior on esd CAN_ERROR_EXT event (3)

[Vincent MAILHOL]

On Tue. 9 Jul. 2022 at 03:15, Frank Jungclaus <frank.jungclaus@esd.eu> wrote:
> Started a rework initiated by Vincents remark about "You should not
> report the greatest of txerr and rxerr but the one which actually
> increased." Now setting CAN_ERR_CRTL_[RT]X_WARNING and
> CAN_ERR_CRTL_[RT]X_PASSIVE depending on REC and TEC
>
> Signed-off-by: Frank Jungclaus <frank.jungclaus@esd.eu>
> ---
>  drivers/net/can/usb/esd_usb.c | 16 +++++++++++-----
>  1 file changed, 11 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/net/can/usb/esd_usb.c b/drivers/net/can/usb/esd_usb.c
> index 0a402a23d7ac..588caba1453b 100644
> --- a/drivers/net/can/usb/esd_usb.c
> +++ b/drivers/net/can/usb/esd_usb.c
> @@ -304,11 +304,17 @@ static void esd_usb_rx_event(struct esd_usb_net_priv *priv,
>                         /* Store error in CAN protocol (location) in data[3] */
>                         cf->data[3] = ecc & SJA1000_ECC_SEG;
>
> -                       if (priv->can.state == CAN_STATE_ERROR_WARNING ||
> -                           priv->can.state == CAN_STATE_ERROR_PASSIVE) {
> -                               cf->data[1] = (txerr > rxerr) ?
> -                                       CAN_ERR_CRTL_TX_PASSIVE :
> -                                       CAN_ERR_CRTL_RX_PASSIVE;
> +                       /* Store error status of CAN-controller in data[1] */
> +                       if (priv->can.state == CAN_STATE_ERROR_WARNING) {
> +                               if (txerr >= 96)
> +                                       cf->data[1] |= CAN_ERR_CRTL_TX_WARNING;

As far as I understand, those flags should be set only when the
threshold is *reached*:
https://elixir.bootlin.com/linux/latest/source/include/uapi/linux/can/error.h#L69

I don't think you should set it if the error state does not change.

Here, you probably want to compare the new value  with the previous
one (stored in struct can_berr_counter) to decide whether or not the
flags should be set.


> +                               if (rxerr >= 96)
> +                                       cf->data[1] |= CAN_ERR_CRTL_RX_WARNING;
> +                       } else if (priv->can.state == CAN_STATE_ERROR_PASSIVE) {
> +                               if (txerr >= 128)
> +                                       cf->data[1] |= CAN_ERR_CRTL_TX_PASSIVE;
> +                               if (rxerr >= 128)
> +                                       cf->data[1] |= CAN_ERR_CRTL_RX_PASSIVE;
>                         }
>
>                         cf->data[6] = txerr;
> --
> 2.25.1
>

Re: [PATCH 6/6] can: esd_usb: Improved decoding for ESD_EV_CAN_ERROR_EXT messages

[Frank Jungclaus]

On Tue, 2022-07-12 at 10:33 +0900, Vincent MAILHOL wrote:
> On Sat. 9 Jul. 2022 at 03:14, Frank Jungclaus <frank.jungclaus@esd.eu> wrote:
> > As suggested by Vincent I spend a union plus a struct ev_can_err_ext
> 
> The canonical way to declare that something was suggested by someone
> else is to use the Suggested-by tag.
> 
> Also, this particular change was suggested by Marc, not by me ;)
> https://lore.kernel.org/linux-can/20220621071152.ggyhrr5sbzvwpkpx@pengutronix.de/

Ops, sorry for mixing up your names. So the kudos goes to Marc ;)
I'll spend a Suggested-by tag and resend patch 6/6.

Best regards,
Frank

> 
> > for easier decoding of an ESD_EV_CAN_ERROR_EXT event message (which
> > simply is a rx_msg with some dedicated data).
> 
> Suggested-by: Marc Kleine-Budde <mkl@pengutronix.de>
> 
> > Signed-off-by: Frank Jungclaus <frank.jungclaus@esd.eu>
> > ---
> >  drivers/net/can/usb/esd_usb.c | 20 ++++++++++++++------
> >  1 file changed, 14 insertions(+), 6 deletions(-)
> > 
> > diff --git a/drivers/net/can/usb/esd_usb.c b/drivers/net/can/usb/esd_usb.c
> > index 09649a45d6ff..2b149590720c 100644
> > --- a/drivers/net/can/usb/esd_usb.c
> > +++ b/drivers/net/can/usb/esd_usb.c
> > @@ -126,7 +126,15 @@ struct rx_msg {
> >         u8 dlc;
> >         __le32 ts;
> >         __le32 id; /* upper 3 bits contain flags */
> > -       u8 data[8];
> > +       union {
> > +               u8 data[8];
> > +               struct {
> > +                       u8 status; /* CAN Controller Status */
> > +                       u8 ecc;    /* Error Capture Register */
> > +                       u8 rec;    /* RX Error Counter */
> > +                       u8 tec;    /* TX Error Counter */
> > +               } ev_can_err_ext;  /* For ESD_EV_CAN_ERROR_EXT */
> > +       };
> >  };
> > 
> >  struct tx_msg {
> > @@ -134,7 +142,7 @@ struct tx_msg {
> >         u8 cmd;
> >         u8 net;
> >         u8 dlc;
> > -       u32 hnd;        /* opaque handle, not used by device */
> > +       u32 hnd;   /* opaque handle, not used by device */
> >         __le32 id; /* upper 3 bits contain flags */
> >         u8 data[8];
> >  };
> > @@ -228,11 +236,11 @@ static void esd_usb_rx_event(struct esd_usb_net_priv *priv,
> >         u32 id = le32_to_cpu(msg->msg.rx.id) & ESD_IDMASK;
> > 
> >         if (id == ESD_EV_CAN_ERROR_EXT) {
> > -               u8 state = msg->msg.rx.data[0];
> > -               u8 ecc   = msg->msg.rx.data[1];
> > +               u8 state = msg->msg.rx.ev_can_err_ext.status;
> > +               u8 ecc   = msg->msg.rx.ev_can_err_ext.ecc;
> > 
> > -               priv->bec.rxerr = msg->msg.rx.data[2];
> > -               priv->bec.txerr = msg->msg.rx.data[3];
> > +               priv->bec.rxerr = msg->msg.rx.ev_can_err_ext.rec;
> > +               priv->bec.txerr = msg->msg.rx.ev_can_err_ext.tec;
> > 
> >                 netdev_dbg(priv->netdev,
> >                            "CAN_ERR_EV_EXT: dlc=%#02x state=%02x ecc=%02x rec=%02x tec=%02x\n",
> 
> Yours sincerely,
> Vincent Mailhol

Re: [PATCH 4/6] can: esd_usb: Improved behavior on esd CAN_ERROR_EXT event (3)

[Frank Jungclaus]

On Tue, 2022-07-12 at 23:39 +0900, Vincent MAILHOL wrote:
> On Tue. 9 Jul. 2022 at 03:15, Frank Jungclaus <frank.jungclaus@esd.eu> wrote:
> > Started a rework initiated by Vincents remark about "You should not
> > report the greatest of txerr and rxerr but the one which actually
> > increased." Now setting CAN_ERR_CRTL_[RT]X_WARNING and
> > CAN_ERR_CRTL_[RT]X_PASSIVE depending on REC and TEC
> > 
> > Signed-off-by: Frank Jungclaus <frank.jungclaus@esd.eu>
> > ---
> >  drivers/net/can/usb/esd_usb.c | 16 +++++++++++-----
> >  1 file changed, 11 insertions(+), 5 deletions(-)
> > 
> > diff --git a/drivers/net/can/usb/esd_usb.c b/drivers/net/can/usb/esd_usb.c
> > index 0a402a23d7ac..588caba1453b 100644
> > --- a/drivers/net/can/usb/esd_usb.c
> > +++ b/drivers/net/can/usb/esd_usb.c
> > @@ -304,11 +304,17 @@ static void esd_usb_rx_event(struct esd_usb_net_priv *priv,
> >                         /* Store error in CAN protocol (location) in data[3] */
> >                         cf->data[3] = ecc & SJA1000_ECC_SEG;
> > 
> > -                       if (priv->can.state == CAN_STATE_ERROR_WARNING ||
> > -                           priv->can.state == CAN_STATE_ERROR_PASSIVE) {
> > -                               cf->data[1] = (txerr > rxerr) ?
> > -                                       CAN_ERR_CRTL_TX_PASSIVE :
> > -                                       CAN_ERR_CRTL_RX_PASSIVE;
> > +                       /* Store error status of CAN-controller in data[1] */
> > +                       if (priv->can.state == CAN_STATE_ERROR_WARNING) {
> > +                               if (txerr >= 96)
> > +                                       cf->data[1] |= CAN_ERR_CRTL_TX_WARNING;
> 
> As far as I understand, those flags should be set only when the
> threshold is *reached*:
> https://elixir.bootlin.com/linux/latest/source/include/uapi/linux/can/error.h#L69
> 
> I don't think you should set it if the error state does not change.
> 
> Here, you probably want to compare the new value  with the previous
> one (stored in struct can_berr_counter) to decide whether or not the
> flags should be set.

Hi Vincent, I didn't interpret the comments given to data[1] in error.h
in that way (obviously). But after checking some other drivers, I see
they all seem to handle it the way you proposed it ...
So, I'll try to rework and resend patch 4/6, too.

Best regards, 
Frank

> 
> 
> > +                               if (rxerr >= 96)
> > +                                       cf->data[1] |= CAN_ERR_CRTL_RX_WARNING;
> > +                       } else if (priv->can.state == CAN_STATE_ERROR_PASSIVE) {
> > +                               if (txerr >= 128)
> > +                                       cf->data[1] |= CAN_ERR_CRTL_TX_PASSIVE;
> > +                               if (rxerr >= 128)
> > +                                       cf->data[1] |= CAN_ERR_CRTL_RX_PASSIVE;
> >                         }
> > 
> >                         cf->data[6] = txerr;
> > --
> > 2.25.1
> >