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Vladimir Oltean 5d14c304bf dpaa_eth: fix usage as DSA master, try 3
The dpaa-eth driver probes on compatible string for the MAC node, and
the fman/mac.c driver allocates a dpaa-ethernet platform device that
triggers the probing of the dpaa-eth net device driver.

All of this is fine, but the problem is that the struct device of the
dpaa_eth net_device is 2 parents away from the MAC which can be
referenced via of_node. So of_find_net_device_by_node can't find it, and
DSA switches won't be able to probe on top of FMan ports.

It would be a bit silly to modify a core function
(of_find_net_device_by_node) to look for dev->parent->parent->of_node
just for one driver. We're just 1 step away from implementing full
recursion.

Actually there have already been at least 2 previous attempts to make
this work:
- Commit a1a50c8e4c ("fsl/man: Inherit parent device and of_node")
- One or more of the patches in "[v3,0/6] adapt DPAA drivers for DSA":
  https://patchwork.ozlabs.org/project/netdev/cover/1508178970-28945-1-git-send-email-madalin.bucur@nxp.com/
  (I couldn't really figure out which one was supposed to solve the
  problem and how).

Point being, it looks like this is still pretty much a problem today.
On T1040, the /sys/class/net/eth0 symlink currently points to

../../devices/platform/ffe000000.soc/ffe400000.fman/ffe4e6000.ethernet/dpaa-ethernet.0/net/eth0

which pretty much illustrates the problem. The closest of_node we've got
is the "fsl,fman-memac" at /soc@ffe000000/fman@400000/ethernet@e6000,
which is what we'd like to be able to reference from DSA as host port.

For of_find_net_device_by_node to find the eth0 port, we would need the
parent of the eth0 net_device to not be the "dpaa-ethernet" platform
device, but to point 1 level higher, aka the "fsl,fman-memac" node
directly. The new sysfs path would look like this:

../../devices/platform/ffe000000.soc/ffe400000.fman/ffe4e6000.ethernet/net/eth0

And this is exactly what SET_NETDEV_DEV does. It sets the parent of the
net_device. The new parent has an of_node associated with it, and
of_dev_node_match already checks for the of_node of the device or of its
parent.

Fixes: a1a50c8e4c ("fsl/man: Inherit parent device and of_node")
Fixes: c6e26ea8c8 ("dpaa_eth: change device used")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-25 17:56:53 -07:00
arch A set of EFI fixes: 2020-05-24 10:24:10 -07:00
block bdi: use bdi_dev_name() to get device name 2020-05-09 16:07:39 -06:00
certs .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
crypto gcc-10: avoid shadowing standard library 'free()' in crypto 2020-05-09 15:58:04 -07:00
Documentation Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-05-23 17:16:18 -07:00
drivers dpaa_eth: fix usage as DSA master, try 3 2020-05-25 17:56:53 -07:00
fs Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-05-23 17:16:18 -07:00
include net/tls: fix race condition causing kernel panic 2020-05-25 17:41:40 -07:00
init A single fix for early boot crashes of kernels built with gcc10 and 2020-05-17 11:08:29 -07:00
ipc ipc/util.c: sysvipc_find_ipc() incorrectly updates position index 2020-05-14 10:00:35 -07:00
kernel A set of fixes for the scheduler: 2020-05-24 10:14:58 -07:00
lib vsprintf: don't obfuscate NULL and error pointers 2020-05-19 11:35:38 -07:00
LICENSES LICENSES: Rename other to deprecated 2019-05-03 06:34:32 -06:00
mm z3fold: fix use-after-free when freeing handles 2020-05-23 10:26:32 -07:00
net net/tls: fix race condition causing kernel panic 2020-05-25 17:41:40 -07:00
samples Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-05-15 13:10:06 -07:00
scripts scripts/gdb: repair rb_first() and rb_last() 2020-05-07 19:27:20 -07:00
security Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-05-23 17:16:18 -07:00
sound sound fixes for 5.7-rc7 2020-05-22 09:22:22 -07:00
tools Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-05-23 17:16:18 -07:00
usr kbuild: fix comment about missing include guard detection 2020-04-11 12:09:48 +09:00
virt KVM: Introduce kvm_make_all_cpus_request_except() 2020-05-08 07:44:32 -04:00
.clang-format clang-format: Update with the latest for_each macro list 2020-04-18 13:49:33 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
.mailmap i2c: use my kernel.org address from now on 2020-05-05 16:29:09 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Hand MIPS over to Thomas 2020-02-24 22:43:18 -08:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig docs: kbuild: convert docs to ReST and rename to *.rst 2019-06-14 14:21:21 -06:00
MAINTAINERS Merge branch 'akpm' (patches from Andrew) 2020-05-23 11:21:47 -07:00
Makefile Linux 5.7-rc6 2020-05-17 16:48:37 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.