linux-toradex.git/drivers/net/usb/r8152.c, branch v6.7-rc8

r8152: add vendor/device ID pair for ASUS USB-C2500

2023-12-06T09:38:38+00:00

The ASUS USB-C2500 is an RTL8156 based 2.5G Ethernet controller.

Add the vendor and product ID values to the driver. This makes Ethernet
work with the adapter.

Signed-off-by: Kelly Kane 
Link: https://lore.kernel.org/r/20231203011712.6314-1-kelly@hawknetworks.com
Signed-off-by: Paolo Abeni

r8152: Add RTL8152_INACCESSIBLE to r8153_aldps_en()

2023-12-04T12:22:01+00:00

Delay loops in r8152 should break out if RTL8152_INACCESSIBLE is set
so that they don't delay too long if the device becomes
inaccessible. Add the break to the loop in r8153_aldps_en().

Fixes: 4214cc550bf9 ("r8152: check if disabling ALDPS is finished")
Reviewed-by: Grant Grundler 
Signed-off-by: Douglas Anderson 
Acked-by: Hayes Wang 
Signed-off-by: David S. Miller

r8152: Add RTL8152_INACCESSIBLE to r8153_pre_firmware_1()

2023-12-04T12:22:01+00:00

Delay loops in r8152 should break out if RTL8152_INACCESSIBLE is set
so that they don't delay too long if the device becomes
inaccessible. Add the break to the loop in r8153_pre_firmware_1().

Fixes: 9370f2d05a2a ("r8152: support request_firmware for RTL8153")
Reviewed-by: Grant Grundler 
Signed-off-by: Douglas Anderson 
Acked-by: Hayes Wang 
Signed-off-by: David S. Miller

r8152: Add RTL8152_INACCESSIBLE to r8156b_wait_loading_flash()

2023-12-04T12:22:01+00:00

Delay loops in r8152 should break out if RTL8152_INACCESSIBLE is set
so that they don't delay too long if the device becomes
inaccessible. Add the break to the loop in
r8156b_wait_loading_flash().

Fixes: 195aae321c82 ("r8152: support new chips")
Reviewed-by: Grant Grundler 
Signed-off-by: Douglas Anderson 
Acked-by: Hayes Wang 
Signed-off-by: David S. Miller

r8152: Add RTL8152_INACCESSIBLE checks to more loops

2023-12-04T12:22:01+00:00

Previous commits added checks for RTL8152_INACCESSIBLE in the loops in
the driver. There are still a few more that keep tripping the driver
up in error cases and make things take longer than they should. Add
those in.

All the loops that are part of this commit existed in some form or
another since the r8152 driver was first introduced, though
RTL8152_INACCESSIBLE was known as RTL8152_UNPLUG before commit
715f67f33af4 ("r8152: Rename RTL8152_UNPLUG to RTL8152_INACCESSIBLE")

Fixes: ac718b69301c ("net/usb: new driver for RTL8152")
Reviewed-by: Grant Grundler 
Signed-off-by: Douglas Anderson 
Acked-by: Hayes Wang 
Signed-off-by: David S. Miller

r8152: Hold the rtnl_lock for all of reset

2023-12-04T12:22:01+00:00

As of commit d9962b0d4202 ("r8152: Block future register access if
register access fails") there is a race condition that can happen
between the USB device reset thread and napi_enable() (not) getting
called during rtl8152_open(). Specifically:
* While rtl8152_open() is running we get a register access error
  that's _not_ -ENODEV and queue up a USB reset.
* rtl8152_open() exits before calling napi_enable() due to any reason
  (including usb_submit_urb() returning an error).

In that case:
* Since the USB reset is perform in a separate thread asynchronously,
  it can run at anytime USB device lock is not held - even before
  rtl8152_open() has exited with an error and caused __dev_open() to
  clear the __LINK_STATE_START bit.
* The rtl8152_pre_reset() will notice that the netif_running() returns
  true (since __LINK_STATE_START wasn't cleared) so it won't exit
  early.
* rtl8152_pre_reset() will then hang in napi_disable() because
  napi_enable() was never called.

We can fix the race by making sure that the r8152 reset routines don't
run at the same time as we're opening the device. Specifically we need
the reset routines in their entirety rely on the return value of
netif_running(). The only way to reliably depend on that is for them
to hold the rntl_lock() mutex for the duration of reset.

Grabbing the rntl_lock() mutex for the duration of reset seems like a
long time, but reset is not expected to be common and the rtnl_lock()
mutex is already held for long durations since the core grabs it
around the open/close calls.

Fixes: d9962b0d4202 ("r8152: Block future register access if register access fails")
Reviewed-by: Grant Grundler 
Signed-off-by: Douglas Anderson 
Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2023-10-26T20:46:28+00:00

Cross-merge networking fixes after downstream PR.

Conflicts:

net/mac80211/rx.c
  91535613b609 ("wifi: mac80211: don't drop all unprotected public action frames")
  6c02fab72429 ("wifi: mac80211: split ieee80211_drop_unencrypted_mgmt() return value")

Adjacent changes:

drivers/net/ethernet/apm/xgene/xgene_enet_main.c
  61471264c018 ("net: ethernet: apm: Convert to platform remove callback returning void")
  d2ca43f30611 ("net: xgene: Fix unused xgene_enet_of_match warning for !CONFIG_OF")

net/vmw_vsock/virtio_transport.c
  64c99d2d6ada ("vsock/virtio: support to send non-linear skb")
  53b08c498515 ("vsock/virtio: initialize the_virtio_vsock before using VQs")

Signed-off-by: Jakub Kicinski

r8152: Block future register access if register access fails

2023-10-22T10:46:18+00:00

Even though the functions to read/write registers can fail, most of
the places in the r8152 driver that read/write register values don't
check error codes. The lack of error code checking is problematic in
at least two ways.

The first problem is that the r8152 driver often uses code patterns
similar to this:
  x = read_register()
  x = x | SOME_BIT;
  write_register(x);

...with the above pattern, if the read_register() fails and returns
garbage then we'll end up trying to write modified garbage back to the
Realtek adapter. If the write_register() succeeds that's bad. Note
that as of commit f53a7ad18959 ("r8152: Set memory to all 0xFFs on
failed reg reads") the "garbage" returned by read_register() will at
least be consistent garbage, but it is still garbage.

It turns out that this problem is very serious. Writing garbage to
some of the hardware registers on the Ethernet adapter can put the
adapter in such a bad state that it needs to be power cycled (fully
unplugged and plugged in again) before it can enumerate again.

The second problem is that the r8152 driver generally has functions
that are long sequences of register writes. Assuming everything will
be OK if a random register write fails in the middle isn't a great
assumption.

One might wonder if the above two problems are real. You could ask if
we would really have a successful write after a failed read. It turns
out that the answer appears to be "yes, this can happen". In fact,
we've seen at least two distinct failure modes where this happens.

On a sc7180-trogdor Chromebook if you drop into kdb for a while and
then resume, you can see:
1. We get a "Tx timeout"
2. The "Tx timeout" queues up a USB reset.
3. In rtl8152_pre_reset() we try to reinit the hardware.
4. The first several (2-9) register accesses fail with a timeout, then
   things recover.

The above test case was actually fixed by the patch ("r8152: Increase
USB control msg timeout to 5000ms as per spec") but at least shows
that we really can see successful calls after failed ones.

On a different (AMD) based Chromebook with a particular adapter, we
found that during reboot tests we'd also sometimes get a transitory
failure. In this case we saw -EPIPE being returned sometimes. Retrying
worked, but retrying is not always safe for all register accesses
since reading/writing some registers might have side effects (like
registers that clear on read).

Let's fully lock out all register access if a register access fails.
When we do this, we'll try to queue up a USB reset and try to unlock
register access after the reset. This is slightly tricker than it
sounds since the r8152 driver has an optimized reset sequence that
only works reliably after probe happens. In order to handle this, we
avoid the optimized reset if probe didn't finish. Instead, we simply
retry the probe routine in this case.

When locking out access, we'll use the existing infrastructure that
the driver was using when it detected we were unplugged. This keeps us
from getting stuck in delay loops in some parts of the driver.

Signed-off-by: Douglas Anderson 
Reviewed-by: Grant Grundler 
Signed-off-by: David S. Miller

r8152: Rename RTL8152_UNPLUG to RTL8152_INACCESSIBLE

2023-10-22T10:46:18+00:00

Whenever the RTL8152_UNPLUG is set that just tells the driver that all
accesses will fail and we should just immediately bail. A future patch
will use this same concept at a time when the driver hasn't actually
been unplugged but is about to be reset. Rename the flag in
preparation for the future patch.

This is a no-op change and just a search and replace.

Signed-off-by: Douglas Anderson 
Reviewed-by: Grant Grundler 
Signed-off-by: David S. Miller

r8152: Check for unplug in r8153b_ups_en() / r8153c_ups_en()

2023-10-22T10:46:18+00:00

If the adapter is unplugged while we're looping in r8153b_ups_en() /
r8153c_ups_en() we could end up looping for 10 seconds (20 ms * 500
loops). Add code similar to what's done in other places in the driver
to check for unplug and bail.

Signed-off-by: Douglas Anderson 
Reviewed-by: Grant Grundler 
Signed-off-by: David S. Miller