linux-stable.git/drivers/net/phy/phy_device.c, branch v5.7

net: phy: propagate an error back to the callers of phy_sfp_probe

2020-05-17T19:43:49+00:00

The compilation warning below reveals that the errors returned from
the sfp_bus_add_upstream() call are not propagated to the callers.
Fix it by returning "ret".

14:37:51 drivers/net/phy/phy_device.c: In function 'phy_sfp_probe':
14:37:51 drivers/net/phy/phy_device.c:1236:6: warning: variable 'ret'
   set but not used [-Wunused-but-set-variable]
14:37:51  1236 |  int ret;
14:37:51       |      ^~~

Fixes: 298e54fa810e ("net: phy: add core phylib sfp support")
Signed-off-by: Leon Romanovsky 
Signed-off-by: David S. Miller

net: phy: don't touch suspended flag if there's no suspend/resume callback

2020-03-27T03:29:51+00:00

So far we set phydev->suspended to true in phy_suspend() even if the
PHY driver doesn't implement the suspend callback. This applies
accordingly for the resume path. The current behavior doesn't cause
any issue I'd be aware of, but it's not logical and misleading,
especially considering the description of the flag:
"suspended: Set to true if this phy has been suspended successfully"

Signed-off-by: Heiner Kallweit 
Reviewed-by: Andrew Lunn 
Reviewed-by: Florian Fainelli 
Signed-off-by: David S. Miller

net: phy: probe PHY drivers synchronously

2020-03-27T02:43:26+00:00

If we have scenarios like

mdiobus_register()
	-> loads PHY driver module(s)
	-> registers PHY driver(s)
	-> may schedule async probe
phydev = mdiobus_get_phy()


or

phydev = phy_device_create()
	-> loads PHY driver module
	-> registers PHY driver
	-> may schedule async probe


then we expect the PHY driver to be bound to the phydev when triggering
the action. This may not be the case in case of asynchronous probing.
Therefore ensure that PHY drivers are probed synchronously.

Default still is sync probing, except async probing is explicitly
requested. I saw some comments that the intention is to promote
async probing for more parallelism in boot process and want to be
prepared for the case that the default is changed to async probing.

Signed-off-by: Heiner Kallweit 
Reviewed-by: Florian Fainelli 
Reviewed-by: Andrew Lunn 
Signed-off-by: David S. Miller

net: phy: use phy_read_poll_timeout() to simplify the code

2020-03-24T05:00:02+00:00

use phy_read_poll_timeout() to replace the poll codes for
simplify the code in phy_poll_reset() function.

Reviewed-by: Andrew Lunn 
Signed-off-by: Dejin Zheng 
Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2020-03-13T05:34:48+00:00

Minor overlapping changes, nothing serious.

Signed-off-by: David S. Miller

net: phy: fix MDIO bus PM PHY resuming

2020-03-12T22:36:12+00:00

So far we have the unfortunate situation that mdio_bus_phy_may_suspend()
is called in suspend AND resume path, assuming that function result is
the same. After the original change this is no longer the case,
resulting in broken resume as reported by Geert.

To fix this call mdio_bus_phy_may_suspend() in the suspend path only,
and let the phy_device store the info whether it was suspended by
MDIO bus PM.

Fixes: 503ba7c69610 ("net: phy: Avoid multiple suspends")
Reported-by: Geert Uytterhoeven 
Tested-by: Geert Uytterhoeven 
Signed-off-by: Heiner Kallweit 
Reviewed-by: Florian Fainelli 
Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2020-02-28T02:31:39+00:00

The mptcp conflict was overlapping additions.

The SMC conflict was an additional and removal happening at the same
time.

Signed-off-by: David S. Miller

net: phy: corrected the return value for genphy_check_and_restart_aneg and genphy_c45_check_and_restart_aneg

2020-02-27T04:41:42+00:00

When auto-negotiation is not required, return value should be zero.

Changes v1->v2:
- improved comments and code as Andrew Lunn and Heiner Kallweit suggestion
- fixed issue in genphy_c45_check_and_restart_aneg as Russell King
  suggestion.

Fixes: 2a10ab043ac5 ("net: phy: add genphy_check_and_restart_aneg()")
Fixes: 1af9f16840e9 ("net: phy: add genphy_c45_check_and_restart_aneg()")
Signed-off-by: Sudheesh Mavila 
Reviewed-by: Heiner Kallweit 
Reviewed-by: Andrew Lunn 
Signed-off-by: David S. Miller

net: phy: Avoid multiple suspends

2020-02-24T04:57:50+00:00

It is currently possible for a PHY device to be suspended as part of a
network device driver's suspend call while it is still being attached to
that net_device, either via phy_suspend() or implicitly via phy_stop().

Later on, when the MDIO bus controller get suspended, we would attempt
to suspend again the PHY because it is still attached to a network
device.

This is both a waste of time and creates an opportunity for improper
clock/power management bugs to creep in.

Fixes: 803dd9c77ac3 ("net: phy: avoid suspending twice a PHY")
Signed-off-by: Florian Fainelli 
Signed-off-by: David S. Miller

phy: avoid unnecessary link-up delay in polling mode

2020-02-20T00:17:28+00:00

commit 93c0970493c71f ("net: phy: consider latched link-down status in
polling mode") removed double-read of latched link-state register for
polling mode from genphy_update_link(). This added extra ~1s delay into
sequence link down->up.
Following scenario:
 - After boot link goes up
 - phy_start() is called triggering an aneg restart, hence link goes
   down and link-down info is latched.
 - After aneg has finished link goes up. In phy_state_machine is checked
   link state but it is latched "link is down". The state machine is
   scheduled after one second and there is detected "link is up". This
   extra delay can be avoided when we keep link-state register double read
   in case when link was down previously.

With this solution we don't miss a link-down event in polling mode and
link-up is faster.

Details about this quirky behavior on Realtek phy:
Without patch:
T0:    aneg is started, link goes down, link-down status is latched
T0+3s: state machine runs, up-to-date link-down is read
T0+4s: state machine runs, aneg is finished (BMSR_ANEGCOMPLETE==1),
       here i read link-down (BMSR_LSTATUS==0),
T0+5s: state machine runs, aneg is finished (BMSR_ANEGCOMPLETE==1),
       up-to-date link-up is read (BMSR_LSTATUS==1),
       phydev->link goes up, state change PHY_NOLINK to PHY_RUNNING

With patch:
T0:    aneg is started, link goes down, link-down status is latched
T0+3s: state machine runs, up-to-date link-down is read
T0+4s: state machine runs, aneg is finished (BMSR_ANEGCOMPLETE==1),
       first BMSR read: BMSR_ANEGCOMPLETE==1 and BMSR_LSTATUS==0,
       second BMSR read: BMSR_ANEGCOMPLETE==1 and BMSR_LSTATUS==1,
       phydev->link goes up, state change PHY_NOLINK to PHY_RUNNING

Signed-off-by: Petr Oros 
Reviewed-by: Heiner Kallweit 
Signed-off-by: David S. Miller