Remove initialisers that set .aneg_done to genphy_aneg_done - this is
the default for clause 22 PHYs, so the initialiser is redundant.
Signed-off-by: NRussell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/phy/mscc.c:1683:3-4: Unneeded semicolon

 Remove unneeded semicolon.

Generated by: scripts/coccinelle/misc/semicolon.cocci

Fixes: 75a1ccfe ("mscc.c: Add support for additional VSC PHYs")
CC: Bryan Whitehead <Bryan.Whitehead@microchip.com>
Signed-off-by: Nkbuild test robot <lkp@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add support for the following VSC PHYs
	VSC8504, VSC8552, VSC8572
	VSC8562, VSC8564, VSC8575, VSC8582

Updates for v2:
	Checked for NULL on input to container_of
	Changed a large if else series to a switch statement.
	Added a WARN_ON to make sure lowest nibble of mask is 0
Signed-off-by: NBryan Whitehead <Bryan.Whitehead@microchip.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Don't populate const arrays on the stack but instead make them
static. Makes the object code smaller by 1058 bytes.

Before:
   text	   data	    bss	    dec	    hex	filename
  29879	   6144	      0	  36023	   8cb7	drivers/net/phy/mscc.o

After:
   text	   data	    bss	    dec	    hex	filename
  28437	   6528	      0	  34965	   8895	drivers/net/phy/mscc.o

(gcc version 9.2.1, amd64)
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>

Supported PHY features are either auto-detected or explicitly set.
In both cases calling genphy_config_init isn't needed. All that
genphy_config_init does is removing features that are set as
supported but can't be auto-detected. Basically it duplicates the
code in genphy_read_abilities. Therefore remove such calls from
all PHY drivers.

v2:
- remove call also from new adin PHY driver
v3:
- pass NULL as config_init function pointer for dp83848
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The memory allocated for the stats array may contain arbitrary data.

Fixes: e4f9ba64 ("net: phy: mscc: add support for VSC8514 PHY.")
Fixes: 00d70d8e ("net: phy: mscc: add support for VSC8574 PHY")
Fixes: a5afc167 ("net: phy: mscc: add support for VSC8584 PHY")
Fixes: f76178dc ("net: phy: mscc: add ethtool statistics counters")
Signed-off-by: NAndreas Schwab <schwab@suse.de>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The VSC8514 PHY is a 4-ports PHY that is 10/100/1000BASE-T, 100BASE-FX,
1000BASE-X, can communicate with the MAC via QSGMII.
The MAC interface protocol for each port within QSGMII can
be either 1000BASE-X or SGMII, if the QSGMII MAC that the VSC8514 is
connecting to supports this functionality.
VSC8514 also supports SGMII MAC-side autonegotiation on each individual
port, downshifting, can set the blinking pattern of each of its 4 LEDs,
SyncE, 1000BASE-T Ring Resiliency as well as HP Auto-MDIX detection.

This adds support for 10BASE-T, 100BASE-TX, and 1000BASE-T,
QSGMII link with the MAC, downshifting, HP Auto-MDIX detection
and blinking pattern for its 4 LEDs.

The GPIO register bank is a set of registers that are common to all PHYs
in the package. So any modification in any register of this bank affects
all PHYs of the package.

If the PHYs haven't been reset before booting the Linux kernel and were
configured to use interrupts for e.g. link status updates, it is
required to clear the interrupts mask register of all PHYs before being
able to use interrupts with any PHY. The first PHY of the package that
will be init will take care of clearing all PHYs interrupts mask
registers. Thus, we need to keep track of the init sequence in the
package, if it's already been done or if it's to be done.

Most of the init sequence of a PHY of the package is common to all PHYs
in the package, thus we use the SMI broadcast feature which enables us
to propagate a write in one register of one PHY to all PHYs in the same
package.
Signed-off-by: NKavya Sree Kotagiri <kavyasree.kotagiri@microchip.com>
Signed-off-by: NQuentin Schulz <quentin.schulz@bootlin.com>
Co-developed-by: NQuentin Schulz <quentin.schulz@bootlin.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Recently genphy_read_abilities() has been added that dynamically detects
clause 22 PHY abilities. I *think* this detection should work with all
supported PHY's, at least for the ones with basic features sets, i.e.
PHY_BASIC_FEATURES and PHY_GBIT_FEATURES. So let's remove setting these
features explicitly and rely on phylib feature detection.

I don't have access to most of these PHY's, therefore I'd appreciate
regression testing.

v2:
- make the feature constant a comment so that readers know which
  features are supported by the respective PHY
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Tested-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Where the license text and the MODULE_LICENSE() value agree, convert
to using an SPDX header, removing the license text.
Signed-off-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

- Turn on Broadcast writes
- UNH 1.8.1 clear bias for UNH 1000BT distortion
- UNH 1.8.7 optimize pre-emphasis for 100BasTx UNH 100W fix
- Enable Token-ring during 'Coma Mode'
Signed-off-by: NRaju Lakkaraju <Raju.Lakkaraju@microchip.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The vsc85xx_default_config function called in the vsc85xx_config_init
function which is used by VSC8530, VSC8531, VSC8540 and VSC8541 PHYs
mistakenly calls phy_read and phy_write in-between phy_select_page and
phy_restore_page.

phy_select_page and phy_restore_page actually take and release the MDIO
bus lock and phy_write and phy_read take and release the lock to write
or read to a PHY register.

Let's fix this deadlock by using phy_modify_paged which handles
correctly a read followed by a write in a non-standard page.

Fixes: 6a0bfbbe ("net: phy: mscc: migrate to phy_select/restore_page functions")
Signed-off-by: NQuentin Schulz <quentin.schulz@bootlin.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now that flag PHY_HAS_INTERRUPT has been replaced with a check for
callbacks config_intr and ack_interrupt, we can remove setting this
flag from all driver configs.
Last but not least remove flag PHY_HAS_INTERRUPT completely.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In case memory resources for *fw* were successfully allocated,
release them before return.

Addresses-Coverity-ID: 1473968 ("Resource leak")
Fixes: 00d70d8e ("net: phy: mscc: add support for VSC8574 PHY")
Reviewed-by: NQuentin Schulz <quentin.schulz@bootlin.com>
Signed-off-by: NGustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently, the error handling for the call to function
phy_read_paged() doesn't work because *reg_val* is of
type u16 (16 bits, unsigned), which makes it impossible
for it to hold a value less than 0.

Fix this by changing the type of variable *reg_val* to int.

Addresses-Coverity-ID: 1473970 ("Unsigned compared against 0")
Fixes: 6a0bfbbe ("net: phy: mscc: migrate to phy_select/restore_page functions")
Reviewed-by: NQuentin Schulz <quentin.schulz@bootlin.com>
Signed-off-by: NGustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The VSC8574 PHY is a 4-ports PHY that is 10/100/1000BASE-T, 100BASE-FX,
1000BASE-X and triple-speed copper SFP capable, can communicate with
the MAC via SGMII, QSGMII or 1000BASE-X, supports WOL, downshifting and
can set the blinking pattern of each of its 4 LEDs, supports SyncE as
well as HP Auto-MDIX detection.

This adds support for 10/100/1000BASE-T, SGMII/QSGMII link with the MAC,
WOL, downshifting, HP Auto-MDIX detection and blinking pattern for its 4
LEDs.

The VSC8574 has also an internal Intel 8051 microcontroller whose
firmware needs to be patched when the PHY is reset. If the 8051's
firmware has the expected CRC, its patching can be skipped. The
microcontroller can be accessed from any port of the PHY, though the CRC
function can only be done through the PHY that is the base PHY of the
package (internal address 0) due to a limitation of the firmware.

The GPIO register bank is a set of registers that are common to all PHYs
in the package. So any modification in any register of this bank affects
all PHYs of the package.

If the PHYs haven't been reset before booting the Linux kernel and were
configured to use interrupts for e.g. link status updates, it is
required to clear the interrupts mask register of all PHYs before being
able to use interrupts with any PHY. The first PHY of the package that
will be init will take care of clearing all PHYs interrupts mask
registers. Thus, we need to keep track of the init sequence in the
package, if it's already been done or if it's to be done.

Most of the init sequence of a PHY of the package is common to all PHYs
in the package, thus we use the SMI broadcast feature which enables us
to propagate a write in one register of one PHY to all PHYs in the same
package.
Signed-off-by: NQuentin Schulz <quentin.schulz@bootlin.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The VSC8584 PHY is a 4-ports PHY that is 10/100/1000BASE-T, 100BASE-FX,
1000BASE-X and triple-speed copper SFP capable, can communicate with the
MAC via SGMII, QSGMII or 1000BASE-X, supports downshifting and can set
the blinking pattern of each of its 4 LEDs, supports hardware offloading
of MACsec and supports SyncE as well as HP Auto-MDIX detection.

This adds support for 10/100/1000BASE-T, SGMII/QSGMII link with the MAC,
downshifting, HP Auto-MDIX detection and blinking pattern for its 4
LEDs.

The VSC8584 has also an internal Intel 8051 microcontroller whose
firmware needs to be patched when the PHY is reset. If the 8051's
firmware has the expected CRC, its patching can be skipped. The
microcontroller can be accessed from any port of the PHY, though the CRC
function can only be done through the PHY that is the base PHY of the
package (internal address 0) due to a limitation of the firmware.

The GPIO register bank is a set of registers that are common to all PHYs
in the package. So any modification in any register of this bank affects
all PHYs of the package.

If the PHYs haven't been reset before booting the Linux kernel and were
configured to use interrupts for e.g. link status updates, it is
required to clear the interrupts mask register of all PHYs before being
able to use interrupts with any PHY. The first PHY of the package that
will be init will take care of clearing all PHYs interrupts mask
registers. Thus, we need to keep track of the init sequence in the
package, if it's already been done or if it's to be done.

Most of the init sequence of a PHY of the package is common to all PHYs
in the package, thus we use the SMI broadcast feature which enables us
to propagate a write in one register of one PHY to all PHYs in the same
package.

The revA of the VSC8584 PHY (which is not and will not be publicly
released) should NOT patch the firmware of the microcontroller or it'll
make things worse, the easiest way is just to not support it.
Signed-off-by: NQuentin Schulz <quentin.schulz@bootlin.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Here, the rc variable is either used only for the condition right after
the assignment or right before being used as the return value of the
function it's being used in.

So let's remove this unneeded temporary variable whenever possible.
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NQuentin Schulz <quentin.schulz@bootlin.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

`if (x != 0)` is basically a more verbose version of `if (x)` so let's
use the latter so it's consistent throughout the whole driver.
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NQuentin Schulz <quentin.schulz@bootlin.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The == operator precedes the || operator, so we can remove the
parenthesis around (a == b) || (c == d).

The condition is rather explicit and short so removing the parenthesis
definitely does not make it harder to read.
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NQuentin Schulz <quentin.schulz@bootlin.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Microsemi PHYs (VSC 8530/31/40/41) need to update the Energy Efficient
Ethernet initialization sequence.
In order to avoid certain link state errors that could result in link
drops and packet loss, the physical coding sublayer (PCS) must be
updated with settings related to EEE in order to improve performance.
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NRaju Lakkaraju <Raju.Lakkaraju@microchip.com>
Signed-off-by: NQuentin Schulz <quentin.schulz@bootlin.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There are a few counters available in the PHY: receive errors, false
carriers, link disconnects, media CRC errors and valids counters.

So let's expose those in the PHY driver.

Use the priv structure as the next PHY to be supported has a few
additional counters.
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NRaju Lakkaraju <Raju.Lakkaraju@microsemi.com>
Signed-off-by: NQuentin Schulz <quentin.schulz@bootlin.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The Microsemi PHYs have multiple banks of registers (called pages).
Registers can only be accessed from one page, if we need a register from
another page, we need to switch the page and the registers of all other
pages are not accessible anymore.

Basically, to read register 5 from page 0, 1, 2, etc., you do the same
phy_read(phydev, 5); but you need to set the desired page beforehand.

In order to guarantee that two concurrent functions do not change the
page, we need to do some locking per page. This can be achieved with the
use of phy_select_page and phy_restore_page functions but phy_write/read
calls in-between those two functions shall be replaced by their
lock-free alternative __phy_write/read.

Let's migrate this driver to those functions.
Suggested-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NQuentin Schulz <quentin.schulz@bootlin.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

gcc points out that the length of the temporary buffer may not be sufficient for
large numbers of leds:

drivers/net/phy/mscc.c: In function 'vsc85xx_probe':
drivers/net/phy/mscc.c:460:45: error: '-mode' directive writing 5 bytes into a region of size between 0 and 9 [-Werror=format-overflow=]
   ret = sprintf(led_dt_prop, "vsc8531,led-%d-mode", i);
                                             ^~~~~
drivers/net/phy/mscc.c:460:9: note: 'sprintf' output between 19 and 28 bytes into a destination of size 22
   ret = sprintf(led_dt_prop, "vsc8531,led-%d-mode", i);
         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

While we can make a reasonable assumption that the number of LEDs is small,
the cost of making the buffer a little bigger is insignificant as well.

Fixes: 11bfdabb ("net: phy: mscc: factorize code for LEDs mode")
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Reviewed-by: NAlexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In the DT binding, it is specified nowhere that 'vsc8531,led-%d-mode' is
an u8, even though it's read as an u8 in the driver.

Let's update the driver to take into consideration that the
'vsc8531,led-%d-mode' property is of the default type u32.
Signed-off-by: NQuentin Schulz <quentin.schulz@bootlin.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In the DT binding, it is specified nowhere that 'vsc8531,edge-slowdown'
is an u8, even though it's read as an u8 in the driver.

Let's update the driver to take into consideration that the
'vsc8531,edge-slowdown' property is of the default type u32.
Signed-off-by: NQuentin Schulz <quentin.schulz@bootlin.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In the DT binding, it is specified nowhere that 'vsc8531,vddmac' is an
u16, even though it's read as an u16 in the driver.

Let's update the driver to take into consideration that the
'vsc8531,vddmac' property is of the default type u32.
Signed-off-by: NQuentin Schulz <quentin.schulz@bootlin.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Microsemi PHYs support different LED modes depending on the variant, so
let's factorize the code so we just have to give the supported modes
while the logic behind getting the mode remains identical.
Signed-off-by: NQuentin Schulz <quentin.schulz@bootlin.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

LEDs modes are set the same way, except they are offset by 4 times the
index of the LED.

Let's factorize all the code so that it's easier to add support for the
4 LEDs of the VSC8584 PHY.
Signed-off-by: NQuentin Schulz <quentin.schulz@bootlin.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The Extended Page Access is a 16-bit register, so change the page
parameter of vsc85xx_phy_page_set to a u16.
Signed-off-by: NQuentin Schulz <quentin.schulz@bootlin.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Reviewed-by: NAlexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

LED Mode:
Microsemi PHY support 2 LEDs (LED[0] and LED[1]) to display different
status information that can be selected by setting LED mode.

LED Mode parameter (vsc8531, led-0-mode) and (vsc8531, led-1-mode) get
from Device Tree.
Signed-off-by: NRaju Lakkaraju <Raju.Lakkaraju@microsemi.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

To connect two ports of the same configuration (MDI to MDI or
MDI-X to MDI-X) with a 10/100/1000 Mbit/s connection, an
Ethernet crossover cable is needed to cross over the transmit
and receive signals in the cable, so that they are matched at
the connector level.
When connecting an MDI port to an MDI-X port a straight through
cable is used while to connect two MDI ports or two MDI-X ports
a crossover cable must be used. Conventionally MDI is used on end
devices while MDI-X is used on hubs and switches

Auto MDI-X automatically detects the required cable connection
type and configures the connection appropriately, removing the
need for crossover cables to interconnect switches or connecting
PCs peer-to-peer.
Signed-off-by: NRaju Lakkaraju <Raju.Lakkaraju@microsemi.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

PHY drivers should be able to rely on the caller of {get,set}_tunable to
have acquired the PHY device mutex, in order to both serialize against
concurrent calls of these functions, but also against PHY state machine
changes. All ethtool PHY-level functions do this, except
{get,set}_tunable, so we make them consistent here as well.

We need to update the Microsemi PHY driver in the same commit to avoid
introducing either deadlocks, or lack of proper locking.

Fixes: 968ad9da ("ethtool: Implements ETHTOOL_PHY_GTUNABLE/ETHTOOL_PHY_STUNABLE")
Fixes: 310d9ad5 ("net: phy: Add downshift get/set support in Microsemi PHYs driver")
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Reviewed-by: NAllan W. Nielsen <allan.nielsen@microsemi.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Implements the phy tunable function pointers and implement downshift
functionality for MSCC PHYs.
Signed-off-by: NRaju Lakkaraju <Raju.Lakkaraju@microsemi.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NAllan W. Nielsen <allan.nielsen@microsemi.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NRaju Lakkaraju <Raju.Lakkaraju@microsemi.com>
Signed-off-by: NAllan W. Nielsen <allan.nielsen@microsemi.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Edge-Rate cleanup include the following:
- Updated device tree bindings documentation for edge-rate
- The edge-rate is now specified as a "slowdown", meaning that it is now
  being specified as positive values instead of negative (both
  documentation and implementation wise).
- Only explicitly documented values for "vsc8531,vddmac" and
  "vsc8531,edge-slowdown" are accepted by the device driver.
- Deleted include/dt-bindings/net/mscc-phy-vsc8531.h as it was not needed.
- Read/validate devicetree settings in probe instead of init
Signed-off-by: NAllan W. Nielsen <allan.nielsen@microsemi.com>
Signed-off-by: NRaju Lakkaraju <raju.lakkaraju@microsemi.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Wake-on-LAN (WoL) is an Ethernet networking standard that allows
a computer/device to be turned on or awakened by a network message.

VSC8531 PHY can support this feature configure by driver set function.
WoL status get by driver get function.

Tested on Beaglebone Black with VSC 8531 PHY.
Signed-off-by: NRaju Lakkaraju <Raju.Lakkaraju@microsemi.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Edge-rate:
As system and networking speeds increase, a signal's output transition,
also know as the edge rate or slew rate (V/ns), takes on greater importance
because high-speed signals come with a price. That price is an assortment of
interference problems like ringing on the line, signal overshoot and
undershoot, extended signal settling times, crosstalk noise, transmission
line reflections, false signal detection by the receiving device and
electromagnetic interference (EMI) -- all of which can negate the potential
gains designers are seeking when they try to increase system speeds through
the use of higher performance logic devices. The fact is, faster signaling
edge rates can cause a higher level of electrical noise or other type of
interference that can actually lead to slower line speeds and lower maximum
system frequencies. This parameter allow the board designers to change the
driving strange, and thereby change the EMI behavioral.

Edge-rate parameters (vddmac, edge-slowdown) get from Device Tree.

Tested on Beaglebone Black with VSC 8531 PHY.
Signed-off-by: NRaju Lakkaraju <Raju.Lakkaraju@microsemi.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

All the review comments updated and resending for review.

This is MAC interface feature.
Microsemi PHY can support RGMII, RMII or GMII/MII interface between MAC and PHY.
MAC-IF function program the right value based on Device tree configuration.

Tested on Beaglebone Black with VSC 8531 PHY.
Signed-off-by: NRaju Lakkaraju <Raju.Lakkaraju@microsemi.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The existing VSC85xx PHY driver did not follow the coding style and caused "checkpatch" to complain. This commit fixes this.
Signed-off-by: NRaju Lakkaraju <Raju.Lakkaraju@microsemi.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In the case where phydev->interrupts is not PHY_INTERRUPT_ENABLED
function vsc85xx_ack_interrupt is returning an uninitialized
garbage value.  Fix this by initializing rc to zero.
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>