net: mdio: fill in missing MODULE_DESCRIPTION()s

W=1 builds now warn if a module is built without a
MODULE_DESCRIPTION(). Fill them in based on the Kconfig text, or
similar.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Acked-by: Andrew Jeffery <andrew@codeconstruct.com.au>
Link: https://lore.kernel.org/r/20231028184458.99448-3-andrew@lunn.ch
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: mdio: aspeed: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.
To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new() which already returns void. Eventually after all drivers
are converted, .remove_new() is renamed to .remove().

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: phy: Remove probe_capabilities

Deciding if to probe of PHYs using C45 is now determine by if the bus
provides the C45 read method. This makes probe_capabilities redundant
so remove it.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Michael Walle <michael@walle.cc>
Reviewed-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Acked-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

net: mdio: aspeed: Separate C22 and C45 transactions

The aspeed MDIO bus driver can perform both C22 and C45 transfers.
Modify the existing C45 functions to take the devad as a parameter,
and remove the wrappers so there are individual C22 and C45 functions. Add
the C45 functions to the new API calls.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: mdio: add reset control for Aspeed MDIO

Add reset assertion/deassertion for Aspeed MDIO. There are 4 MDIO
controllers embedded in Aspeed AST2600 SOC and share one reset control
register SCU50[3]. To work with old DT blobs which don't have the reset
property, devm_reset_control_get_optional_shared is used in this change.

Signed-off-by: Dylan Hung <dylan_hung@aspeedtech.com>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

net: mdio: aspeed: Add c45 support

Add Clause 45 support for Aspeed mdio driver.

Signed-off-by: Potin Lai <potin.lai@quantatw.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: mdio: aspeed: Introduce read write function for c22 and c45

Add following additional functions to move out the implementation from
aspeed_mdio_read() and aspeed_mdio_write().

c22:
- aspeed_mdio_read_c22()
- aspeed_mdio_write_c22()

c45:
- aspeed_mdio_read_c45()
- aspeed_mdio_write_c45()

Signed-off-by: Potin Lai <potin.lai@quantatw.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: mdio: aspeed: move reg accessing part into separate functions

Add aspeed_mdio_op() and aseed_mdio_get_data() for register accessing.

aspeed_mdio_op() handles operations, write command to control register,
then check and wait operations is finished (bit 31 is cleared).

aseed_mdio_get_data() fetchs the result value of operation from data
register.

Signed-off-by: Potin Lai <potin.lai@quantatw.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: mdio: aspeed: Add missing MODULE_DEVICE_TABLE

Fix loading of the driver when built as a module.

Fixes: f160e99462c6 ("net: phy: Add mdio-aspeed")
Signed-off-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Acked-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

mdio: aspeed: Fix "Link is Down" issue

The issue happened randomly in runtime. The message "Link is Down" is
popped but soon it recovered to "Link is Up".

The "Link is Down" results from the incorrect read data for reading the
PHY register via MDIO bus. The correct sequence for reading the data
shall be:
1. fire the command
2. wait for command done (this step was missing)
3. wait for data idle
4. read data from data register

Cc: stable@vger.kernel.org
Fixes: f160e99462c6 ("net: phy: Add mdio-aspeed")
Reviewed-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Dylan Hung <dylan_hung@aspeedtech.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Link: https://lore.kernel.org/r/20211125024432.15809-1-dylan_hung@aspeedtech.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: mdio: Move MDIO drivers into a new subdirectory

Move all the MDIO drivers and multiplexers into drivers/net/mdio. The
mdio core is however left in the phy directory, due to mutual
dependencies between the MDIO core and the PHY core.

Take this opportunity to sort the Kconfig based on the menuconfig
strings, and move the multiplexers to the end with a separating
comment.

v2:
Fix typo in commit message

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