mdio_mux_init() use the parameter dev for two distinct thing:
1) Have a device for all devm_ functions
2) Get device_node from it
Since it is two distinct purpose, this patch add a parameter mdio_mux
that is linked to task 2.
This will also permit to register an of_node mdio-mux that lacks a direct
owning device.
For example a mdio-mux which is a subnode of a real device.
Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
mdio_mux_uninit() call put_device (unconditionally) because of
of_mdio_find_bus() in mdio_mux_init.
But of_mdio_find_bus is only called if mux_bus is empty.
If mux_bus is set, mdio_mux_uninit will print a "refcount_t: underflow"
trace.
This patch add a get_device in the other branch of "if (mux_bus)".
Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove the driver version information because this information
is not useful in an upstream kernel driver.
Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch fix checkpatch warning about unnecessary 'out of memory'
message.
Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch fix checkpatch warning about NULL Comparison style.
Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now that we have a custom printf format specifier, convert users of
full_name to use %pOF instead. This is preparation to remove storing
of the full path string for each node.
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
mdio_mux_init parses the child nodes of the MDIO mux. When using
"mdio-mux-mmioreg" the child nodes are describing the register value
that is written to switch between the MDIO busses.
The change which makes the error messages more verbose changed the
parsing of the "reg" property from a simple of_property_read_u32 call
to of_mdio_parse_addr. On a Khadas VIM (based on the Meson GXL SoC,
which uses mdio-mux-mmioreg) this prevents registering the MDIO mux
(because the "reg" values on the MDIO mux child nodes are 0x2009087f
and 0xe40908ff) and leads to the following errors:
mdio-mux-mmioreg c883455c.eth-phy-mux: /soc/periphs@c8834000/eth-phy-mux/mdio@e40908ff PHY address -469169921 is too large
mdio-mux-mmioreg c883455c.eth-phy-mux: Error: Failed to find reg for child /soc/periphs@c8834000/eth-phy-mux/mdio@e40908ff
mdio-mux-mmioreg c883455c.eth-phy-mux: /soc/periphs@c8834000/eth-phy-mux/mdio@2009087f PHY address 537462911 is too large
mdio-mux-mmioreg c883455c.eth-phy-mux: Error: Failed to find reg for child /soc/periphs@c8834000/eth-phy-mux/mdio@2009087f
mdio-mux-mmioreg c883455c.eth-phy-mux: Error: No acceptable child buses found
mdio-mux-mmioreg c883455c.eth-phy-mux: failed to register mdio-mux bus /soc/periphs@c8834000/eth-phy-mux
(as a result of that ethernet is not working, because the PHY which is
connected through the mux' child MDIO bus, which is not being
registered).
Fix this by reverting the change from of_mdio_parse_addr to
of_mdio_parse_addr.
Fixes: 342fa19644 ("mdio: mux: make child bus walking more permissive and errors more verbose")
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
The u32 variable v is being checked to see if an error return is
less than zero and this check has no effect because it is unsigned.
Fix this by making v and int (this also matches the type of
cb->bus_number which is assigned to the value in v).
Detected by CoverityScan, CID#1440454 ("Unsigned compared against zero")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If any errors are encountered while walking the device tree structure of
the MDIO bus for children, the code may silently continue, silently
exit, or throw an error and exit. This make it difficult for device
tree writers to know there is an error. Also, it makes any error in a
child entry of the MDIO bus be fatal for all entries. Instead, we
should provide verbose errors describing the error and then attempt to
continue if it all possible. Also, use of_mdio_parse_addr()
Signed-off-by: Jon Mason <jon.mason@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Device node iterators put the previous value of the index variable, so an
explicit put causes a double put.
In particular, of_mdiobus_register can fail before doing anything
interesting, so one could view it as a no-op from the reference count
point of view.
Generated by: scripts/coccinelle/iterators/device_node_continue.cocci
CC: Jon Mason <jon.mason@broadcom.com>
Signed-off-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is a potential unnecessary refcount decrement on error path of
put_device(&pb->mii_bus->dev), as it is possible to avoid the
of_mdio_find_bus() call if mux_bus is specified by the calling function.
The same put_device() is not called in the error path if the
devm_kzalloc of pb fails. This caused the variable used in the
put_device() to be changed, as the pb pointer was obviously not set up.
There is an unnecessary of_node_get() on child_bus_node if the
of_mdiobus_register() is successful, as the
for_each_available_child_of_node() automatically increments this.
Thus the refcount on this node will always be +1 more than it should be.
There is no of_node_put() on child_bus_node if the of_mdiobus_register()
call fails.
Finally, it is lacking devm_kfree() of pb in the error path. While this
might not be technically necessary, it was present in other parts of the
function. So, I am adding it where necessary to make it uniform.
Signed-off-by: Jon Mason <jon.mason@broadcom.com>
Fixes: f20e6657a8 ("mdio: mux: Enhanced MDIO mux framework for integrated multiplexers")
Fixes: 0ca2997d14 ("netdev/of/phy: Add MDIO bus multiplexer support.")
Signed-off-by: David S. Miller <davem@davemloft.net>
The latest changes to the MDIO code introduced a false-positive
warning with gcc-6 (possibly others):
drivers/net/phy/mdio-mux.c: In function 'mdio_mux_init':
drivers/net/phy/mdio-mux.c:188:3: error: 'parent_bus_node' may be used uninitialized in this function [-Werror=maybe-uninitialized]
It's easy to avoid the warning by making sure the parent_bus_node
is initialized in both cases at the start of the function, since
the later 'of_node_put()' call is also valid for a NULL pointer
argument.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: f20e6657a8 ("mdio: mux: Enhanced MDIO mux framework for integrated multiplexers")
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
An integrated multiplexer uses same address space for
"muxed bus selection" and "generation of mdio transaction"
hence its good to register parent bus from mux driver.
Hence added a mechanism where mux driver could register a
parent bus and pass it down to framework via mdio_mux_init api.
Signed-off-by: Pramod Kumar <pramod.kumar@broadcom.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>
MDIO devices can be stacked upon each other. The current code supports
two levels, which until recently has been enough for a DSA mdio bus on
top of another bus. Now we have hardware which has an MDIO mux in the
middle.
Define an MDIO MUTEX class with three levels.
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Have mdio_alloc() create the array of interrupt numbers, and
initialize it to POLLING. This is what most MDIO drivers want, so
allowing code to be removed from the drivers.
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>
mdiobus_alloc() might return NULL, but its return value is not
checked in mdio_mux_init(). This could potentially lead to a NULL
pointer dereference. Fix it by checking the return value
Fixes: 0ca2997d14 ("netdev/of/phy: Add MDIO bus multiplexer support.")
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
for_each_available_child_of_node performs an of_node_get on each iteration, so
a break out of the loop requires an of_node_put.
A simplified version of the semantic patch that fixes this problem is as
follows (http://coccinelle.lip6.fr):
// <smpl>
@@
local idexpression r.n;
expression r,e;
@@
for_each_available_child_of_node(r,n) {
...
(
of_node_put(n);
|
e = n
|
+ of_node_put(n);
? break;
)
...
}
... when != n
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
of_mdio_find_bus() leaks a struct device refcount, caused by using
class_find_device() and not realising that the device reference has
its refcount incremented:
* Note, you will need to drop the reference with put_device() after use.
...
while ((dev = class_dev_iter_next(&iter))) {
if (match(dev, data)) {
get_device(dev);
break;
}
Update the comment, and arrange for the phy code to drop this refcount
when disposing of a reference to it.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
The mdio-mux driver scans all child mdio nodes, without regard to whether
the node is actually used. Some device trees include all possible
mdio-mux nodes and rely on the boot loader to disable those that are not
present, based on some run-time configuration. Those nodes need to be
skipped.
Signed-off-by: Timur Tabi <timur@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
With lockdep enabled we get:
=============================================
[ INFO: possible recursive locking detected ]
3.4.4-Cavium-Octeon+ #313 Not tainted
---------------------------------------------
kworker/u:1/36 is trying to acquire lock:
(&bus->mdio_lock){+.+...}, at: [<ffffffff813da7e8>] mdio_mux_read+0x38/0xa0
but task is already holding lock:
(&bus->mdio_lock){+.+...}, at: [<ffffffff813d79e4>] mdiobus_read+0x44/0x88
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&bus->mdio_lock);
lock(&bus->mdio_lock);
*** DEADLOCK ***
May be due to missing lock nesting notation
.
.
.
This is a false positive, since we are indeed using 'nested' locking,
we need to use mutex_lock_nested().
Now in theory we can stack multiple MDIO multiplexers, but that would
require passing the nesting level (which is difficult to know) to
mutex_lock_nested(). Instead we assume the simple case of a single
level of nesting. Since these are only warning messages, it isn't so
important to solve the general case.
Signed-off-by: David Daney <david.daney@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds a somewhat generic framework for MDIO bus
multiplexers. It is modeled on the I2C multiplexer.
The multiplexer is needed if there are multiple PHYs with the same
address connected to the same MDIO bus adepter, or if there is
insufficient electrical drive capability for all the connected PHY
devices.
Conceptually it could look something like this:
------------------
| Control Signal |
--------+---------
|
--------------- --------+------
| MDIO MASTER |---| Multiplexer |
--------------- --+-------+----
| |
C C
h h
i i
l l
d d
| |
--------- A B ---------
| | | | | |
| PHY@1 +-------+ +---+ PHY@1 |
| | | | | |
--------- | | ---------
--------- | | ---------
| | | | | |
| PHY@2 +-------+ +---+ PHY@2 |
| | | |
--------- ---------
This framework configures the bus topology from device tree data. The
mechanics of switching the multiplexer is left to device specific
drivers.
The follow-on patch contains a multiplexer driven by GPIO lines.
Signed-off-by: David Daney <david.daney@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
