2022-12-19 21:31:43

by Frank Jungclaus

Subject: [PATCH 1/3] can: esd_usb: Improved behavior on esd CAN_ERROR_EXT event (1)

Moved the supply for cf->data[3] (bit stream position of CAN error)
outside of the "switch (ecc & SJA1000_ECC_MASK){}"-statement, because
this position is independent of the error type.

Fixes: 96d8e90382dc ("can: Add driver for esd CAN-USB/2 device")
Signed-off-by: Frank Jungclaus <[email protected]>
---
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 42323f5e6f3a..5e182fadd875 100644
--- a/drivers/net/can/usb/esd_usb.c
+++ b/drivers/net/can/usb/esd_usb.c
@@ -286,7 +286,6 @@ 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;
}

@@ -294,6 +293,9 @@ static void esd_usb_rx_event(struct esd_usb_net_priv *priv,
if (!(ecc & SJA1000_ECC_DIR))
cf->data[2] |= CAN_ERR_PROT_TX;

+ /* Bit stream position in CAN frame as the error was detected */
+ 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

2022-12-20 05:37:44

by Vincent MAILHOL

Subject: Re: [PATCH 1/3] can: esd_usb: Improved behavior on esd CAN_ERROR_EXT event (1)

On Tue. 20 Dec. 2022 at 06:25, Frank Jungclaus <[email protected]> wrote:
>
> Moved the supply for cf->data[3] (bit stream position of CAN error)
> outside of the "switch (ecc & SJA1000_ECC_MASK){}"-statement, because
> this position is independent of the error type.
>
> Fixes: 96d8e90382dc ("can: Add driver for esd CAN-USB/2 device")
> Signed-off-by: Frank Jungclaus <[email protected]>
> ---
> 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 42323f5e6f3a..5e182fadd875 100644
> --- a/drivers/net/can/usb/esd_usb.c
> +++ b/drivers/net/can/usb/esd_usb.c
> @@ -286,7 +286,6 @@ 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;
> }
>
> @@ -294,6 +293,9 @@ static void esd_usb_rx_event(struct esd_usb_net_priv *priv,
> if (!(ecc & SJA1000_ECC_DIR))
> cf->data[2] |= CAN_ERR_PROT_TX;
>
> + /* Bit stream position in CAN frame as the error was detected */
> + cf->data[3] = ecc & SJA1000_ECC_SEG;

Can you confirm that the value returned by the device matches the
specifications from linux/can/error.h?

https://elixir.bootlin.com/linux/latest/source/include/uapi/linux/can/error.h#L90

> if (priv->can.state == CAN_STATE_ERROR_WARNING ||
> priv->can.state == CAN_STATE_ERROR_PASSIVE) {
> cf->data[1] = (txerr > rxerr) ?
> --
> 2.25.1
>

2022-12-21 17:57:03

by Frank Jungclaus

Subject: Re: [PATCH 1/3] can: esd_usb: Improved behavior on esd CAN_ERROR_EXT event (1)

On Tue, 2022-12-20 at 14:16 +0900, Vincent MAILHOL wrote:
> On Tue. 20 Dec. 2022 at 06:25, Frank Jungclaus <[email protected]> wrote:
> >
> > Moved the supply for cf->data[3] (bit stream position of CAN error)
> > outside of the "switch (ecc & SJA1000_ECC_MASK){}"-statement, because
> > this position is independent of the error type.
> >
> > Fixes: 96d8e90382dc ("can: Add driver for esd CAN-USB/2 device")
> > Signed-off-by: Frank Jungclaus <[email protected]>
> > ---
> > 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 42323f5e6f3a..5e182fadd875 100644
> > --- a/drivers/net/can/usb/esd_usb.c
> > +++ b/drivers/net/can/usb/esd_usb.c
> > @@ -286,7 +286,6 @@ 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;
> > }
> >
> > @@ -294,6 +293,9 @@ static void esd_usb_rx_event(struct esd_usb_net_priv *priv,
> > if (!(ecc & SJA1000_ECC_DIR))
> > cf->data[2] |= CAN_ERR_PROT_TX;
> >
> > + /* Bit stream position in CAN frame as the error was detected */
> > + cf->data[3] = ecc & SJA1000_ECC_SEG;
>
> Can you confirm that the value returned by the device matches the
> specifications from linux/can/error.h?

The value returned is supposed to be compatible to the SJA1000 ECC
register.

See
https://esd.eu/fileadmin/esd/docs/manuals/NTCAN_Part1_Function_API_Manual_en_56.pdf

Chapter "6.2.10 EV_CAN_ERROR_EXT" (page 185)
and
"Annex B: Bus Error Code" table 37 and 38 (page 272 and following).

So this should be compliant with the values given in linux/can/error.h.


>
> https://elixir.bootlin.com/linux/latest/source/include/uapi/linux/can/error.h#L90
>
> > if (priv->can.state == CAN_STATE_ERROR_WARNING ||
> > priv->can.state == CAN_STATE_ERROR_PASSIVE) {
> > cf->data[1] = (txerr > rxerr) ?
> > --
> > 2.25.1
> >

2022-12-22 01:23:27

by Vincent MAILHOL

Subject: Re: [PATCH 1/3] can: esd_usb: Improved behavior on esd CAN_ERROR_EXT event (1)

On Tue. 22 Dec. 2022 at 02:55, Frank Jungclaus <[email protected]> wrote:
> On Tue, 2022-12-20 at 14:16 +0900, Vincent MAILHOL wrote:
> > On Tue. 20 Dec. 2022 at 06:25, Frank Jungclaus <[email protected]> wrote:
> > >
> > > Moved the supply for cf->data[3] (bit stream position of CAN error)
> > > outside of the "switch (ecc & SJA1000_ECC_MASK){}"-statement, because
> > > this position is independent of the error type.
> > >
> > > Fixes: 96d8e90382dc ("can: Add driver for esd CAN-USB/2 device")
> > > Signed-off-by: Frank Jungclaus <[email protected]>
> > > ---
> > > 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 42323f5e6f3a..5e182fadd875 100644
> > > --- a/drivers/net/can/usb/esd_usb.c
> > > +++ b/drivers/net/can/usb/esd_usb.c
> > > @@ -286,7 +286,6 @@ 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;
> > > }
> > >
> > > @@ -294,6 +293,9 @@ static void esd_usb_rx_event(struct esd_usb_net_priv *priv,
> > > if (!(ecc & SJA1000_ECC_DIR))
> > > cf->data[2] |= CAN_ERR_PROT_TX;
> > >
> > > + /* Bit stream position in CAN frame as the error was detected */
> > > + cf->data[3] = ecc & SJA1000_ECC_SEG;
> >
> > Can you confirm that the value returned by the device matches the
> > specifications from linux/can/error.h?
>
> The value returned is supposed to be compatible to the SJA1000 ECC
> register.
>
> See
> https://esd.eu/fileadmin/esd/docs/manuals/NTCAN_Part1_Function_API_Manual_en_56.pdf
>
> Chapter "6.2.10 EV_CAN_ERROR_EXT" (page 185)
> and
> "Annex B: Bus Error Code" table 37 and 38 (page 272 and following).
>
> So this should be compliant with the values given in linux/can/error.h.

Thanks for the link. It is indeed compliant.

Reviewed-by: Vincent Mailhol <[email protected]>

> > https://elixir.bootlin.com/linux/latest/source/include/uapi/linux/can/error.h#L90
> >
> > > if (priv->can.state == CAN_STATE_ERROR_WARNING ||
> > > priv->can.state == CAN_STATE_ERROR_PASSIVE) {
> > > cf->data[1] = (txerr > rxerr) ?
> > > --
> > > 2.25.1
> > >
>