On Fri, Nov 15, 2024 at 11:23:49PM +0100, Vincent Mailhol wrote:
> On 15/11/2024 at 17:15, Sean Nyekjaer wrote:
> > This is added in preparation for calling standby mode in the tcan4x5x
> > driver or other users of m_can.
> > For the tcan4x5x; If Vsup 12V, standby mode will save 7-8mA, when the
> > interface is down.
> >
> > Signed-off-by: Sean Nyekjaer <sean@xxxxxxxxxx>
> > ---
> > drivers/net/can/m_can/m_can.c | 10 +++++++---
> > drivers/net/can/m_can/m_can.h | 1 +
> > 2 files changed, 8 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c
> > index a7b3bc439ae596527493a73d62b4b7a120ae4e49..667c70f8dc5e7e8b15b667119b63dea1fe667e8a 100644
> > --- a/drivers/net/can/m_can/m_can.c
> > +++ b/drivers/net/can/m_can/m_can.c
> > @@ -1750,12 +1750,16 @@ static void m_can_stop(struct net_device *dev)
> >
> > /* Set init mode to disengage from the network */
> > ret = m_can_cccr_update_bits(cdev, CCCR_INIT, CCCR_INIT);
> > - if (ret)
> > - netdev_err(dev, "failed to enter standby mode: %pe\n",
> > - ERR_PTR(ret));
> >
> > /* set the state as STOPPED */
> > cdev->can.state = CAN_STATE_STOPPED;
> > +
> > + if (!ret && cdev->ops->deinit)
> > + ret = cdev->ops->deinit(cdev);
>
> Question: is there a reason not to try to deinit() even if the
> m_can_cccr_update_bits() failed?
Good question.
If the call the m_can core fails, then there bigger problems than setting
the (in nmy case) tcan4x5x in standby mode.
>
> > + if (ret)
> > + netdev_err(dev, "failed to enter standby mode: %pe\n",
> > + ERR_PTR(ret));> }
> >
> > static int m_can_close(struct net_device *dev)
> > diff --git a/drivers/net/can/m_can/m_can.h b/drivers/net/can/m_can/m_can.h
> > index 92b2bd8628e6b31370f4accbc2e28f3b2257a71d..6206535341a22a68d7c5570f619e6c4d05e6fcf4 100644
> > --- a/drivers/net/can/m_can/m_can.h
> > +++ b/drivers/net/can/m_can/m_can.h
> > @@ -68,6 +68,7 @@ struct m_can_ops {
> > int (*write_fifo)(struct m_can_classdev *cdev, int addr_offset,
> > const void *val, size_t val_count);
> > int (*init)(struct m_can_classdev *cdev);
> > + int (*deinit)(struct m_can_classdev *cdev);
> > };
> >
> > struct m_can_tx_op {
> >
>
> Yours sincerely,
> Vincent Mailhol
>
/Sean
