Russell suggested to remove the locking from phy_is_started() because
the read is atomic anyway and actually the locking may be more
misleading.

Fixes: 2b3e88ea ("net: phy: improve phy state checking")
Suggested-by: Russell King - ARM Linux admin <linux@armlinux.org.uk>
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

phylib enables interrupts before phy_start() has been called, and if
we receive an interrupt in a non-started state, the interrupt handler
returns IRQ_NONE. This causes problems with at least one Marvell chip
as reported by Andrew.
Fix this by handling interrupts the same as in phy_mac_interrupt(),
basically always running the phylib state machine. It knows when it
has to do something and when not.
This change allows to handle interrupts gracefully even if they
occur in a non-started state.

Fixes: 2b3e88ea ("net: phy: improve phy state checking")
Reported-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When adding checks to detect wrong usage of the phylib API we added
a check to phy_start_aneg() which is too strict. If the phylib
state machine is in state PHY_HALTED we should allow reconfiguring
and restarting aneg, and just don't touch the state.

Fixes: 2b3e88ea ("net: phy: improve phy state checking")
Reported-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Tested-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

So far phy_error() silently stops the PHY state machine. If the network
driver doesn't inform about a  MDIO error then the user may wonder why
his network is down. Let's print the stack trace to facilitate search
for the root cause of the error.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Add helpers phy_is_started() and __phy_is_started() to avoid open-coded
checks whether PHY has been started. To make the check easier move
PHY_HALTED before PHY_UP in enum phy_state. Further improvements:

phy_start_aneg():
Return -EBUSY and print warning if function is called from a non-started
state (DOWN, READY, HALTED). Better check because function is exported
and drivers may use it incorrectly.

phy_interrupt():
Return IRQ_NONE also if state is DOWN or READY. We should never receive
an interrupt in one of these states, but better play safe.

phy_stop():
Just return and print a warning if PHY is in a non-started state.
This warning should help to identify drivers with unbalanced calls to
phy_start() / phy_stop().

phy_state_machine():
Schedule state machine run only if PHY is in a started state.
E.g. if state is READY we don't need the state machine, it will be
started by phy_start().

v2:
- don't use __func__ within phy_warn_state
v3:
- use WARN() instead of printing error message to facilitate debugging

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When the MII_ADVERTISE register is modified by the IOCTL handler,
phydev->advertising needs recalculating. Use the _mod_ variant of
mii_adv_to_linkmode_adv_t so that bits outside of the advertise
registers are not cleared.

Fixes: c0ec3c27 ("net: phy: Convert u32 phydev->lp_advertising to linkmode")
Reported-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

So far the two functions consider neither member eee_enabled nor
eee_active. Therefore network drivers have to do this in some kind
of glue code. I think this can be avoided.

Getting EEE parameters:
When not advertising any EEE mode, we can't consider EEE to be enabled.
Therefore interpret "EEE enabled" as "we advertise at least one EEE
mode". It's similar with "EEE active": interpret it as "EEE modes
advertised by both link partner have at least one mode in common".

Setting EEE parameters:
If eee_enabled isn't set, don't advertise any EEE mode and restart
aneg if needed to switch off EEE. If eee_enabled is set and
data->advertised is empty (e.g. because EEE was disabled), advertise
everything we support as default. This way EEE can easily switched
on/off by doing ethtool --set-eee <if> eee on/off, w/o any additional
parameters.

The changes to both functions shouldn't break any existing user.
Once the changes have been applied, at least some users can be
simplified.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

A recent change modified variable advertising from a u32 to a link mode
array and left the u32 zero comparison, so essential we now have an array
being compared to null which is not the intention. Fix this by using the
call to linkmode_empty to check if advertising is all zero.

Detected by CoverityScan, CID#1475424 ("Array compared against 0")

Fixes: 3c1bcc86 ("net: ethernet: Convert phydev advertize and supported from u32 to link mode")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

Convert phy drivers to report the link partner advertised modes using
a linkmode bitmap. This allows them to report the higher speeds which
don't fit in a u32.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

There are a few MAC/PHYs combinations which now support > 1Gbps. These
may need to make use of link modes with bits > 31. Thus their
supported PHY features or advertised features cannot be implemented
using the current bitmap in a u32. Convert to using a linkmode bitmap,
which can support all the currently devices link modes, and is future
proof as more modes are added.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

Both states aren't used. Most likely they result from an idea that
never materialized. So remove them.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Now that phy_mac_interrupt() doesn't call phy_change() any longer it's
called from phy_interrupt() only. Therefore phy_interrupt_is_valid()
returns true always and the check can be removed.
In case of PHY_HALTED phy_interrupt() bails out immediately,
therefore the second check for PHY_HALTED including the call to
phy_disable_interrupts() can be removed.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When using phy_mac_interrupt() the irq number is set to
PHY_IGNORE_INTERRUPT, therefore phy_interrupt_is_valid() returns false.
As a result phy_change() effectively just calls phy_trigger_machine()
when called from phy_mac_interrupt() via phy_change_work(). So we can
call phy_trigger_machine() from phy_mac_interrupt() directly and
remove some now unneeded code.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

State PHY_CHANGELINK isn't needed here, we can call the state machine
directly. We just have to remove the check for phy_polling_mode() to
make this work also in interrupt mode. Removing this check doesn't
cause any overhead because when not polling the state machine is
called only if required by some event.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

As a heritage from the very early days of phylib member interrupts is
defined as u32 even though it's just a flag whether interrupts are
enabled. So we can change it to a bitfield member. In addition change
the code dealing with this member in a way that it's clear we're
dealing with a bool value.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Use phy_check_link_status in more places in the state machine.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

After the recent changes in the state machine state PHY_AN isn't used
any longer and can be removed.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

In few places in the state machine the state is set to PHY_RUNNING or
PHY_NOLINK after doing a phy_read_status(). So factor this out to
phy_check_link_status().

First use it in phy_start_aneg(): By setting the state to PHY_RUNNING
or PHY_NOLINK directly we can remove the code to handle the case that
we're using interrupts and aneg was finished already.

Definition of phy_link_up and phy_link_down needs to be moved because
they are called in the new function.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

If aneg isn't finished yet then the PHY reports the link as down.
There's no benefit in setting the state to PHY_AN because the next
state machine run would set the status to PHY_NOLINK anyway (except
in the meantime aneg has been finished and link is up). Therefore
we can set the state to PHY_RUNNING or PHY_NOLINK directly.

In addition change the do_carrier parameter in phy_link_down() to true.
If carrier was marked as up before (what should never be the case because
PHY was in state PHY_HALTED before) then we should mark it as down now.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

If aneg is enabled and the PHY reports the link as up then definitely
aneg finished successfully. Therefore this check is useless and
can be removed.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

phy_trigger_machine() is used in phy.c only, so we can make it static.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

After commit 9f2959b6 ("net: phy: improve handling delayed work")
the sync parameter isn't needed any longer in phy_start_aneg_priv().
This allows to merge phy_start_aneg() and phy_start_aneg_priv().

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Simplify code for handling state PHY_RESUMING, no functional change
intended.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Handling of state PHY_RUNNING seems to be more complex than it needs
to be. If not polling, then we don't have to do anything, we'll
receive an interrupt and go to state PHY_CHANGELINK once the link
goes down. If polling and link is down, we don't have to go the
extra mile over PHY_CHANGELINK and call phy_read_status() again
but can set status PHY_NOLINK directly.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When starting the state machine there may be work to be done
immediately, e.g. if the initial state is PHY_UP then the state
machine may trigger an autonegotiation. Having said that I see no need
to wait a second until the state machine is run first time.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Using mod_delayed_work() allows to simplify handling delayed work and
removes the need for the sync parameter in phy_trigger_machine().
Also introduce a helper phy_queue_state_machine() to encapsulate the
low-level delayed work calls. No functional change intended.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When being in state PHY_HALTED we don't have to reschedule the
state machine, phy_start() will start it again.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

phy_stop() may be called e.g. when suspending, therefore all needed
actions should be performed synchronously. Therefore add a synchronous
call to the state machine.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Add a helper for checking whether polling is used to detect PHY status
changes.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

genphy_config_aneg() should be called only by PHYs that implement
the Clause 22 register set. Prevent Clause 45 PHYs that don't implement
the register set from calling the genphy function.

Signed-off-by: Camelia Groza <camelia.groza@nxp.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

The situation described in the comment can occur also with
PHY_IGNORE_INTERRUPT, therefore change the condition to include it.

Fixes: f555f34f ("net: phy: fix auto-negotiation stall due to unavailable interrupt")
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

Some network drivers include functionality to speed down the PHY when
suspending and just waiting for a WoL packet because this saves energy.
This functionality is quite generic, therefore let's factor it out to
phylib.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This functionality will also be needed in subsequent patches of this
series, therefore factor it out to a helper.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

We can bail out immediately also in case of PHY_IGNORE_INTERRUPT because
phy_mac_interupt() informs us once the link is up.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

After commit c59530d0 ("net: Move PHY statistics code into PHY
library helpers") we made net/core/ethtool.c reference symbols which are
part of the library which can be modular. David introduced a temporary
fix with 1ecd6e8a ("phy: Temporary build fix after phylib changes.")
which would prevent such modularity.

This is not desireable of course, so instead, just inline the functions
into include/linux/phy.h to keep both options available.

Fixes: c59530d0 ("net: Move PHY statistics code into PHY library helpers")
Fixes: 1ecd6e8a ("phy: Temporary build fix after phylib changes.")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

In order to make it possible for network device drivers that do not
necessarily have a phy_device attached, but still report PHY statistics,
have a preliminary refactoring consisting in creating helper functions
that encapsulate the PHY device driver knowledge within PHYLIB.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

In 664fcf12 (net: phy: Threaded interrupts allow some simplification)
the phy_interrupt system was changed to use a traditional threaded
interrupt scheme instead of a workqueue approach.

With this change, the phy status check moved into phy_change, which
did not report back to the caller whether or not the interrupt was
handled. This means that, in the case of a shared phy interrupt,
only the first phydev's interrupt registers are checked (since
phy_interrupt() would always return IRQ_HANDLED). This leads to
interrupt storms when it is a secondary device that's actually the
interrupt source.

Signed-off-by: Brad Mouring <brad.mouring@ni.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Now that phy_disable_interrupts() can't take lock phydev->lock any longer,
we can use it to simplify phy_stop().

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

All callers of phy_disable_interrupts() call phy_error() in the error
case. Therefore we don't need to do this within the function too.
This change also allows us to use phy_disable_interrupts() in code
holding phydev->lock (because phy_error() can take this lock).

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

commit f5e64032 ("net: phy: fix resume handling") changes the
locking semantics for phy_resume() such that the caller now needs to
hold the phy mutex. Not all call sites were adopted to this new
semantic, resulting in warnings from the added
WARN_ON(!mutex_is_locked(&phydev->lock)).  Rather than change the
semantics, add a __phy_resume() and restore the old behavior of
phy_resume().

Reported-by: Heiner Kallweit <hkallweit1@gmail.com>
Fixes: f5e64032 ("net: phy: fix resume handling")
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>