diff mbox series

[2/2] net: usb: ax88179_178a: avoid two consecutive device resets

Message ID 20231114125111.313229-3-jtornosm@redhat.com (mailing list archive)
State New, archived
Headers show
Series net: usb: ax88179_178a: fix and improve reset procedure | expand

Commit Message

Jose Ignacio Tornos Martinez Nov. 14, 2023, 12:50 p.m. UTC 
The device is always reset two consecutive times (ax88179_reset is called
twice), one from usbnet_probe during the device binding and the other from
usbnet_open.

Let only the reset during the device binding to prepare the device as soon
as possible and not repeat the reset operation (tested with generic ASIX
Electronics Corp. AX88179 Gigabit Ethernet device).

Reported-by: Herb Wei <weihao.bj@ieisystem.com>
Tested-by: Herb Wei <weihao.bj@ieisystem.com>
Signed-off-by: Jose Ignacio Tornos Martinez <jtornosm@redhat.com>
---
 drivers/net/usb/ax88179_178a.c | 13 -------------
 1 file changed, 13 deletions(-)

Comments

Paolo Abeni Nov. 16, 2023, 9:42 a.m. UTC | #1 
On Tue, 2023-11-14 at 13:50 +0100, Jose Ignacio Tornos Martinez wrote:
> The device is always reset two consecutive times (ax88179_reset is called
> twice), one from usbnet_probe during the device binding and the other from
> usbnet_open.
> 
> Let only the reset during the device binding to prepare the device as soon
> as possible and not repeat the reset operation (tested with generic ASIX
> Electronics Corp. AX88179 Gigabit Ethernet device).
> 
> Reported-by: Herb Wei <weihao.bj@ieisystem.com>
> Tested-by: Herb Wei <weihao.bj@ieisystem.com>
> Signed-off-by: Jose Ignacio Tornos Martinez <jtornosm@redhat.com>

We need a suitable Fixes tag even here ;)

> ---
>  drivers/net/usb/ax88179_178a.c | 13 -------------
>  1 file changed, 13 deletions(-)
> 
> diff --git a/drivers/net/usb/ax88179_178a.c b/drivers/net/usb/ax88179_178a.c
> index 4ea0e155bb0d..864c6fc2db33 100644
> --- a/drivers/net/usb/ax88179_178a.c
> +++ b/drivers/net/usb/ax88179_178a.c
> @@ -1678,7 +1678,6 @@ static const struct driver_info ax88179_info = {
>  	.unbind = ax88179_unbind,
>  	.status = ax88179_status,
>  	.link_reset = ax88179_link_reset,
> -	.reset = ax88179_reset,
>  	.stop = ax88179_stop,
>  	.flags = FLAG_ETHER | FLAG_FRAMING_AX,
>  	.rx_fixup = ax88179_rx_fixup,

This looks potentially dangerous, as the device will not get a reset in
down/up cycles; *possibly* dropping the reset call from ax88179_bind()
would be safer.

In both cases touching so many H/W variant with testing available on a
single one sounds dangerous. Is the unneeded 2nd reset causing any
specific issue?

Thanks,

Paolo
Jose Ignacio Tornos Martinez Nov. 16, 2023, 2:18 p.m. UTC | #2 
On Thu, Nov 16, 2023 at 10:42 AM Paolo Abeni <pabeni@redhat.com> wrote:
> We need a suitable Fixes tag even here ;)
Ok, I will add it in my next version.

> > ---
> >  drivers/net/usb/ax88179_178a.c | 13 -------------
> >  1 file changed, 13 deletions(-)
> >
> > diff --git a/drivers/net/usb/ax88179_178a.c b/drivers/net/usb/ax88179_178a.c
> > index 4ea0e155bb0d..864c6fc2db33 100644
> > --- a/drivers/net/usb/ax88179_178a.c
> > +++ b/drivers/net/usb/ax88179_178a.c
> > @@ -1678,7 +1678,6 @@ static const struct driver_info ax88179_info = {
> >       .unbind = ax88179_unbind,
> >       .status = ax88179_status,
> >       .link_reset = ax88179_link_reset,
> > -     .reset = ax88179_reset,
> >       .stop = ax88179_stop,
> >       .flags = FLAG_ETHER | FLAG_FRAMING_AX,
> >       .rx_fixup = ax88179_rx_fixup,
>
> This looks potentially dangerous, as the device will not get a reset in
> down/up cycles; *possibly* dropping the reset call from ax88179_bind()
> would be safer.
Ok, I had the doubt about which reset would be the best, because it seemed 
to me that reset would be better as soon as possible.
I will try what you say to avoid down/up cycles.

> In both cases touching so many H/W variant with testing available on a
> single one sounds dangerous. Is the unneeded 2nd reset causing any
> specific issue?
Actually, this double reboot somewhat masked the first problem, because the
probability of getting a successful initialization, if there is a previous
problem seems to be higher. So, it is not strictly needed but I think it is 
better to avoid a second unnecessary reset.
Ok, if I modify the call from ax88179_bind() I will be respecting the reset
operation of all devices.

Thanks

Best regards
José Ignacio
diff mbox series

Patch

diff --git a/drivers/net/usb/ax88179_178a.c b/drivers/net/usb/ax88179_178a.c
index 4ea0e155bb0d..864c6fc2db33 100644
--- a/drivers/net/usb/ax88179_178a.c
+++ b/drivers/net/usb/ax88179_178a.c
@@ -1678,7 +1678,6 @@  static const struct driver_info ax88179_info = {
 	.unbind = ax88179_unbind,
 	.status = ax88179_status,
 	.link_reset = ax88179_link_reset,
-	.reset = ax88179_reset,
 	.stop = ax88179_stop,
 	.flags = FLAG_ETHER | FLAG_FRAMING_AX,
 	.rx_fixup = ax88179_rx_fixup,
@@ -1691,7 +1690,6 @@  static const struct driver_info ax88178a_info = {
 	.unbind = ax88179_unbind,
 	.status = ax88179_status,
 	.link_reset = ax88179_link_reset,
-	.reset = ax88179_reset,
 	.stop = ax88179_stop,
 	.flags = FLAG_ETHER | FLAG_FRAMING_AX,
 	.rx_fixup = ax88179_rx_fixup,
@@ -1704,7 +1702,6 @@  static const struct driver_info cypress_GX3_info = {
 	.unbind = ax88179_unbind,
 	.status = ax88179_status,
 	.link_reset = ax88179_link_reset,
-	.reset = ax88179_reset,
 	.stop = ax88179_stop,
 	.flags = FLAG_ETHER | FLAG_FRAMING_AX,
 	.rx_fixup = ax88179_rx_fixup,
@@ -1717,7 +1714,6 @@  static const struct driver_info dlink_dub1312_info = {
 	.unbind = ax88179_unbind,
 	.status = ax88179_status,
 	.link_reset = ax88179_link_reset,
-	.reset = ax88179_reset,
 	.stop = ax88179_stop,
 	.flags = FLAG_ETHER | FLAG_FRAMING_AX,
 	.rx_fixup = ax88179_rx_fixup,
@@ -1730,7 +1726,6 @@  static const struct driver_info sitecom_info = {
 	.unbind = ax88179_unbind,
 	.status = ax88179_status,
 	.link_reset = ax88179_link_reset,
-	.reset = ax88179_reset,
 	.stop = ax88179_stop,
 	.flags = FLAG_ETHER | FLAG_FRAMING_AX,
 	.rx_fixup = ax88179_rx_fixup,
@@ -1743,7 +1738,6 @@  static const struct driver_info samsung_info = {
 	.unbind = ax88179_unbind,
 	.status = ax88179_status,
 	.link_reset = ax88179_link_reset,
-	.reset = ax88179_reset,
 	.stop = ax88179_stop,
 	.flags = FLAG_ETHER | FLAG_FRAMING_AX,
 	.rx_fixup = ax88179_rx_fixup,
@@ -1756,7 +1750,6 @@  static const struct driver_info lenovo_info = {
 	.unbind = ax88179_unbind,
 	.status = ax88179_status,
 	.link_reset = ax88179_link_reset,
-	.reset = ax88179_reset,
 	.stop = ax88179_stop,
 	.flags = FLAG_ETHER | FLAG_FRAMING_AX,
 	.rx_fixup = ax88179_rx_fixup,
@@ -1769,7 +1762,6 @@  static const struct driver_info belkin_info = {
 	.unbind = ax88179_unbind,
 	.status = ax88179_status,
 	.link_reset = ax88179_link_reset,
-	.reset	= ax88179_reset,
 	.stop	= ax88179_stop,
 	.flags	= FLAG_ETHER | FLAG_FRAMING_AX,
 	.rx_fixup = ax88179_rx_fixup,
@@ -1782,7 +1774,6 @@  static const struct driver_info toshiba_info = {
 	.unbind = ax88179_unbind,
 	.status = ax88179_status,
 	.link_reset = ax88179_link_reset,
-	.reset	= ax88179_reset,
 	.stop = ax88179_stop,
 	.flags	= FLAG_ETHER | FLAG_FRAMING_AX,
 	.rx_fixup = ax88179_rx_fixup,
@@ -1795,7 +1786,6 @@  static const struct driver_info mct_info = {
 	.unbind	= ax88179_unbind,
 	.status	= ax88179_status,
 	.link_reset = ax88179_link_reset,
-	.reset	= ax88179_reset,
 	.stop	= ax88179_stop,
 	.flags	= FLAG_ETHER | FLAG_FRAMING_AX,
 	.rx_fixup = ax88179_rx_fixup,
@@ -1808,7 +1798,6 @@  static const struct driver_info at_umc2000_info = {
 	.unbind = ax88179_unbind,
 	.status = ax88179_status,
 	.link_reset = ax88179_link_reset,
-	.reset  = ax88179_reset,
 	.stop   = ax88179_stop,
 	.flags  = FLAG_ETHER | FLAG_FRAMING_AX,
 	.rx_fixup = ax88179_rx_fixup,
@@ -1821,7 +1810,6 @@  static const struct driver_info at_umc200_info = {
 	.unbind = ax88179_unbind,
 	.status = ax88179_status,
 	.link_reset = ax88179_link_reset,
-	.reset  = ax88179_reset,
 	.stop   = ax88179_stop,
 	.flags  = FLAG_ETHER | FLAG_FRAMING_AX,
 	.rx_fixup = ax88179_rx_fixup,
@@ -1834,7 +1822,6 @@  static const struct driver_info at_umc2000sp_info = {
 	.unbind = ax88179_unbind,
 	.status = ax88179_status,
 	.link_reset = ax88179_link_reset,
-	.reset  = ax88179_reset,
 	.stop   = ax88179_stop,
 	.flags  = FLAG_ETHER | FLAG_FRAMING_AX,
 	.rx_fixup = ax88179_rx_fixup,