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>

This condition wasn't adjusted when PHY_IGNORE_INTERRUPT (-2) was added
long ago. In case of PHY_IGNORE_INTERRUPT the MAC interrupt indicates
also PHY state changes and we should do what the symbol says.

Fixes: 84a527a4 ("net: phylib: fix interrupts re-enablement in phy_start")
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>

I see two issues with parameter new_link:

1. It's not needed. See also phy_interrupt(), works w/o this parameter.
   phy_mac_interrupt sets the state to PHY_CHANGELINK and triggers the
   state machine which then calls phy_read_status. And phy_read_status
   updates the link state.

2. phy_mac_interrupt is used in interrupt context and getting the link
   state may sleep (at least when having to access the PHY registers
   via MDIO bus).

So let's remove it.

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

When a PHY has the BMCR_PDOWN bit set, it may decide to ignore writes
to other registers, or reset the registers to power-on defaults.
Micrel PHYs do this for their interrupt registers.

The current structure of phylib tries to enable interrupts before
resuming (and releasing) the BMCR_PDOWN bit.  This fails, causing
Micrel PHYs to stop working after a suspend/resume sequence if they
are using interrupts.

Fix this by ensuring that the PHY driver resume methods do not take
the phydev->lock mutex themselves, but the callers of phy_resume()
take that lock.  This then allows us to move the call to phy_resume()
before we enable interrupts in phy_start().

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

If state is not PHY_HALTED I see no need to temporarily disable
interrupts on the device. As long as the current interrupt isn't acked
on the device no new interrupt can happen anyway.

In addition remove a unneeded enabling of interrupts in the state
machine when handling state PHY_CHANGELINK.

Tested on a Odroid-C2 with RTL8211F phy in interrupt mode.

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

After commits c974bdbc "net: phy: Use threaded IRQ, to allow IRQ from
sleeping devices" and 664fcf12 "net: phy: Threaded interrupts allow
some simplification" all relevant code pieces run in process context
anyway and I don't think we need the disabling of interrupts any longer.

Interestingly enough, latter commit already removed the comment
explaining why interrupts need to be temporarily disabled.

On my system phy interrupt mode works fine with this patch.
However I may miss something, especially in the context of shared phy
interrupts, therefore I'd appreciate if more people could test this.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

read_status and config_aneg are the only mandatory callbacks and most
of the time the generic implementation is used by drivers.
So make the core fall back to the generic version if a driver doesn't
implement the respective callback.

Also currently the core doesn't seem to verify that drivers implement
the mandatory calls. If a driver doesn't do so we'd just get a NPE.
With this patch this potential issue doesn't exit any longer.

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>

With commit 2d55173e ("phy: add generic function to support
ksetting support"), we lost the ability to report the transceiver type
like we used to. Now that we have added back the transceiver type to
ethtool_link_settings, we can report it back like we used to and have no
loss of information.

Fixes: 3f1ac7a7 ("net: ethtool: add new ETHTOOL_xLINKSETTINGS API")
Fixes: 2d55173e ("phy: add generic function to support ksetting support")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This reverts commit 7ad813f2 ("net: phy:
Correctly process PHY_HALTED in phy_stop_machine()") because it is
creating the possibility for a NULL pointer dereference.

David Daney provide the following call trace and diagram of events:

When ndo_stop() is called we call:

 phy_disconnect()
    +---> phy_stop_interrupts() implies: phydev->irq = PHY_POLL;
    +---> phy_stop_machine()
    |      +---> phy_state_machine()
    |              +----> queue_delayed_work(): Work queued.
    +--->phy_detach() implies: phydev->attached_dev = NULL;

Now at a later time the queued work does:

 phy_state_machine()
    +---->netif_carrier_off(phydev->attached_dev): Oh no! It is NULL:

 CPU 12 Unable to handle kernel paging request at virtual address
0000000000000048, epc == ffffffff80de37ec, ra == ffffffff80c7c
Oops[#1]:
CPU: 12 PID: 1502 Comm: kworker/12:1 Not tainted 4.9.43-Cavium-Octeon+ #1
Workqueue: events_power_efficient phy_state_machine
task: 80000004021ed100 task.stack: 8000000409d70000
$ 0   : 0000000000000000 ffffffff84720060 0000000000000048 0000000000000004
$ 4   : 0000000000000000 0000000000000001 0000000000000004 0000000000000000
$ 8   : 0000000000000000 0000000000000000 00000000ffff98f3 0000000000000000
$12   : 8000000409d73fe0 0000000000009c00 ffffffff846547c8 000000000000af3b
$16   : 80000004096bab68 80000004096babd0 0000000000000000 80000004096ba800
$20   : 0000000000000000 0000000000000000 ffffffff81090000 0000000000000008
$24   : 0000000000000061 ffffffff808637b0
$28   : 8000000409d70000 8000000409d73cf0 80000000271bd300 ffffffff80c7804c
Hi    : 000000000000002a
Lo    : 000000000000003f
epc   : ffffffff80de37ec netif_carrier_off+0xc/0x58
ra    : ffffffff80c7804c phy_state_machine+0x48c/0x4f8
Status: 14009ce3        KX SX UX KERNEL EXL IE
Cause : 00800008 (ExcCode 02)
BadVA : 0000000000000048
PrId  : 000d9501 (Cavium Octeon III)
Modules linked in:
Process kworker/12:1 (pid: 1502, threadinfo=8000000409d70000,
task=80000004021ed100, tls=0000000000000000)
Stack : 8000000409a54000 80000004096bab68 80000000271bd300 80000000271c1e00
        0000000000000000 ffffffff808a1708 8000000409a54000 80000000271bd300
        80000000271bd320 8000000409a54030 ffffffff80ff0f00 0000000000000001
        ffffffff81090000 ffffffff808a1ac0 8000000402182080 ffffffff84650000
        8000000402182080 ffffffff84650000 ffffffff80ff0000 8000000409a54000
        ffffffff808a1970 0000000000000000 80000004099e8000 8000000402099240
        0000000000000000 ffffffff808a8598 0000000000000000 8000000408eeeb00
        8000000409a54000 00000000810a1d00 0000000000000000 8000000409d73de8
        8000000409d73de8 0000000000000088 000000000c009c00 8000000409d73e08
        8000000409d73e08 8000000402182080 ffffffff808a84d0 8000000402182080
        ...
Call Trace:
[<ffffffff80de37ec>] netif_carrier_off+0xc/0x58
[<ffffffff80c7804c>] phy_state_machine+0x48c/0x4f8
[<ffffffff808a1708>] process_one_work+0x158/0x368
[<ffffffff808a1ac0>] worker_thread+0x150/0x4c0
[<ffffffff808a8598>] kthread+0xc8/0xe0
[<ffffffff808617f0>] ret_from_kernel_thread+0x14/0x1c

The original motivation for this change originated from Marc Gonzales
indicating that his network driver did not have its adjust_link callback
executing with phydev->link = 0 while he was expecting it.

PHYLIB has never made any such guarantees ever because phy_stop() merely just
tells the workqueue to move into PHY_HALTED state which will happen
asynchronously.

Reported-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reported-by: David Daney <ddaney.cavm@gmail.com>
Fixes: 7ad813f2 ("net: phy: Correctly process PHY_HALTED in phy_stop_machine()")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

phylink will need phy_start_machine exported, so lets export it as a
GPL symbol.  Documentation/networking/phy.txt indicates that this
should be a PHY API function.

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

Sometimes, we need to do additional work between the PHY coming up and
marking the carrier present - for example, we may need to wait for the
PHY to MAC link to finish negotiation.  This changes phylib to provide
a notification function pointer which avoids the built-in
netif_carrier_on() and netif_carrier_off() functions.

Standard ->adjust_link functionality is provided by hooking a helper
into the new ->phy_link_change method.

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>