Hi Vincent,
On Wed, Mar 8, 2023 at 4:55 PM Vincent Mailhol
<vincent.mailhol@xxxxxxxxx> wrote:
> On Wed. 8 Mar. 2023 at 22:20, Geert Uytterhoeven
> <geert+renesas@xxxxxxxxx> wrote:
> > Add support for CAN transceivers described as PHYs.
> >
> > While simple CAN transceivers can do without, this is needed for CAN
> > transceivers like NXP TJR1443 that need a configuration step (like
> > pulling standby or enable lines), and/or impose a bitrate limit.
> >
> > Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
> > Reviewed-by: Simon Horman <simon.horman@xxxxxxxxxxxx>
>
> I have one nitpick (see below). Aside from that:
> Reviewed-by: Vincent Mailhol <mailhol.vincent@xxxxxxxxxx>
Thanks!
>
> > ---
> > v2:
> > - Add Reviewed-by.
> > ---
> > drivers/net/can/rcar/rcar_canfd.c | 30 +++++++++++++++++++++++++-----
> > 1 file changed, 25 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/net/can/rcar/rcar_canfd.c b/drivers/net/can/rcar/rcar_canfd.c
> > index ef4e1b9a9e1ee280..6df9a259e5e4f92c 100644
> > --- a/drivers/net/can/rcar/rcar_canfd.c
> > +++ b/drivers/net/can/rcar/rcar_canfd.c
> > @@ -35,6 +35,7 @@
> > #include <linux/netdevice.h>
> > #include <linux/of.h>
> > #include <linux/of_device.h>
> > +#include <linux/phy/phy.h>
> > #include <linux/platform_device.h>
> > #include <linux/reset.h>
> > #include <linux/types.h>
> > @@ -530,6 +531,7 @@ struct rcar_canfd_channel {
> > struct net_device *ndev;
> > struct rcar_canfd_global *gpriv; /* Controller reference */
> > void __iomem *base; /* Register base address */
> > + struct phy *transceiver; /* Optional transceiver */
> > struct napi_struct napi;
> > u32 tx_head; /* Incremented on xmit */
> > u32 tx_tail; /* Incremented on xmit done */
> > @@ -1413,11 +1415,17 @@ static int rcar_canfd_open(struct net_device *ndev)
> > struct rcar_canfd_global *gpriv = priv->gpriv;
> > int err;
> >
> > + err = phy_power_on(priv->transceiver);
> > + if (err) {
> > + netdev_err(ndev, "failed to power on PHY, error %d\n", err);
> > + return err;
> > + }
> > +
> > /* Peripheral clock is already enabled in probe */
> > err = clk_prepare_enable(gpriv->can_clk);
> > if (err) {
> > netdev_err(ndev, "failed to enable CAN clock, error %d\n", err);
> ^^
>
> Nitpick: can you print the mnemotechnic instead of the error value?
>
> netdev_err(ndev, "failed to enable CAN clock, error
> %pe\n", ERR_PTR(err));
Thanks for the suggestion!
As you're pointing to pre-existing code, and there are several cases
like that, I sent a follow-up patch to fix all of them at once:
https://lore.kernel.org/r/8a39f99fc28967134826dff141b51a5df824b034.1678349267.git.geert+renesas@xxxxxxxxx
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
