linux-toradex.git/drivers/net/phy/mdio_bus.c, branch v3.0.91

phylib: fix PAL state machine restart on resume

2010-09-14T21:31:03+00:00

On resume, before starting the PAL state machine, check if the
adjust_link() method is well supplied. If not, this would lead to a
NULL pointer dereference in the phy_state_machine() function.

This scenario can happen if the Ethernet driver call manually the PHY
functions instead of using the PAL state machine. The mv643xx_eth driver
is a such example.

Signed-off-by: Simon Guinot 
Signed-off-by: David S. Miller

NET: Support clause 45 MDIO commands at the MDIO bus level

2010-03-17T04:23:42+00:00

IEEE 802.3ae clause 45 specifies a somewhat modified MDIO protocol
for use by 10GIGE phys. The main change is a 21 bit address split into
a 5 bit device ID and a 16 bit register offset. The definition is designed
so that normal and extended devices can run on the same MDIO bus.

Extend mdio-bitbang to do the new protocol. At the MDIO bus level the
protocol is requested by or'ing MII_ADDR_C45 into the register offset.

Make phy_read/phy_write/etc pass a full 32 bit register offset.

This does not attempt to make the phy layer support C45 style PHYs, just
to provide the MDIO bus support.

Tested against a Broadcom 10GE phy with ID 0x206034, and several
Broadcom 10/100/1000 Phys in normal mode.

Signed-off-by: Jason Gunthorpe 
Signed-off-by: David S. Miller

phylib: Properly reinitialize PHYs after hibernation

2009-12-31T06:03:42+00:00

Since hibernation assumes power loss, we should fully reinitialize
PHYs (including platform fixups), as if PHYs were just attached.

This patch factors phy_init_hw() out of phy_attach_direct(), then
converts mdio_bus to dev_pm_ops and adds an appropriate restore()
callback.

Signed-off-by: Anton Vorontsov 
Signed-off-by: David S. Miller

phylib: Fix deadlock on resume

2009-12-31T06:03:41+00:00

Sometimes kernel hangs on resume with the following trace:

 ucc_geth e0102000.ucc: resume
 INFO: task bash:1764 blocked for more than 120 seconds.
 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
 bash          D 0fecf43c     0  1764   1763 0x00000000
 Call Trace:
 [cf9a7c10] [c0012868] ret_from_except+0x0/0x14 (unreliable)
 --- Exception: cf9a7ce0 at __switch_to+0x4c/0x6c
     LR = 0xcf9a7cc0
 [cf9a7cd0] [c0008c14] __switch_to+0x4c/0x6c (unreliable)
 [cf9a7ce0] [c028bcfc] schedule+0x158/0x260
 [cf9a7d10] [c028c720] __mutex_lock_slowpath+0x80/0xd8
 [cf9a7d40] [c01cf388] phy_stop+0x20/0x70
 [cf9a7d50] [c01d514c] ugeth_resume+0x6c/0x13c
 [...]

Here is why.

On suspend:

- PM core starts suspending devices, ucc_geth_suspend gets called;

- ucc_geth calls phy_stop() on suspend. Note that phy_stop() is
  mostly asynchronous so it doesn't block ucc_geth's suspend routine,
  it just sets PHY_HALTED state and disables PHY's interrupts;

- Suddenly the state machine gets scheduled, it grabs the phydev->lock
  mutex and tries to process the PHY_HALTED state, so it calls
  phydev->adjust_link(phydev->attached_dev). In ucc_geth case
  adjust_link() calls msleep(), which reschedules the code flow back to
  PM core, which now finishes suspend and so we end up sleeping with
  phydev->lock mutex held.

On resume:

- PM core starts resuming devices (notice that nobody rescheduled
  the state machine yet, so the mutex is still held), the core calls
  ucc_geth's resume routine;

- ucc_geth_resume restarts the PHY with phy_stop()/phy_start()
  sequence, and the phy_*() calls are trying to grab the phydev->lock
  mutex. Here comes the deadlock.

This patch fixes the issue by stopping the state machine on suspend
and starting it again on resume.

Signed-off-by: Anton Vorontsov 
Signed-off-by: David S. Miller

phylib: rework to prepare for OF registration of PHYs

2009-04-27T09:53:45+00:00

This patch makes changes in preparation for supporting open firmware
device tree descriptions of MDIO busses.  Changes include:
- Cleanup handling of phy_map[] entries; they are already NULLed when
  registering and so don't need to be re-cleared, and it is good practice
  to clear them out when unregistering.
- Split phy_device registration out into a new function so that the
  OF helpers can do two stage registration (separate allocation and
  registration steps).

Signed-off-by: Grant Likely 
Acked-by: Andy Fleming 
Signed-off-by: David S. Miller

mdio: fix non-constant printk warnings

2009-02-27T06:22:03+00:00

Signed-off-by: Stephen Hemminger 
Signed-off-by: David S. Miller

phylib: Rework suspend/resume code to check netdev wakeup capability

2009-02-01T08:53:34+00:00

In most cases (e.g. PCI drivers) MDIO and MAC controllers are
represented by the same device. But for SOC ethernets we have
separate devices. So, in SOC case, checking whether MDIO
controller may wakeup is not only makes little sense, but also
prevents us from doing per-netdevice wakeup management.

This patch reworks suspend/resume code so that now it checks
for net device's wakeup flags, not MDIO controller's ones.

Each netdevice should manage its wakeup flags, and phylib will
decide whether suspend an attached PHY or not.

Signed-off-by: Anton Vorontsov 
Signed-off-by: David S. Miller

phylib: Fix oops in suspend/resume paths

2009-01-22T21:51:24+00:00

Suspend/resume routines check for phydrv != NULL, but that is
wrong because "phydrv" comes from container_of(drv). If drv is NULL,
then container_of(drv) will return non-NULL result, and the checks
won't work.

The Freescale TBI PHYs are driver-less, so "drv" is NULL, and that
leads to the following oops:

Unable to handle kernel paging request for data at address 0xffffffe4
Faulting instruction address: 0xc0215554
Oops: Kernel access of bad area, sig: 11 [#1]
[...]
NIP [c0215554] mdio_bus_suspend+0x34/0x70
LR [c01cc508] suspend_device+0x258/0x2bc
Call Trace:
[cfad3da0] [cfad3db8] 0xcfad3db8 (unreliable)
[cfad3db0] [c01cc508] suspend_device+0x258/0x2bc
[cfad3dd0] [c01cc62c] dpm_suspend+0xc0/0x140
[cfad3e20] [c01cc6f4] device_suspend+0x48/0x5c
[cfad3e40] [c0068dd8] suspend_devices_and_enter+0x8c/0x148
[cfad3e60] [c00690f8] enter_state+0x100/0x118
[cfad3e80] [c00691c0] state_store+0xb0/0xe4
[cfad3ea0] [c018c938] kobj_attr_store+0x24/0x3c
[cfad3eb0] [c00ea9a8] flush_write_buffer+0x58/0x7c
[cfad3ed0] [c00eadf0] sysfs_write_file+0x58/0xa0
[cfad3ef0] [c009e810] vfs_write+0xb4/0x16c
[cfad3f10] [c009ed40] sys_write+0x4c/0x90
[cfad3f40] [c0014954] ret_from_syscall+0x0/0x38
[...]

This patch fixes the issue, plus removes unneeded parentheses
and fixes indentation level in mdio_bus_suspend().

Signed-off-by: Anton Vorontsov 
Signed-off-by: David S. Miller

net: PHYLIB mdio fixes #2

2008-12-26T00:50:41+00:00

The PHYLIB mdio code has more problems in error paths:
- mdiobus_release can be called before bus->state is set to
  MDIOBUS_REGISTERED
- mdiobus_scan allocates resources which need to be freed
- the comment is wrong, the resistors used are actually pull-ups.

Signed-off-by: Krzysztof Halasa 
Signed-off-by: David S. Miller

Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6

2008-12-24T01:56:23+00:00

Conflicts:

	drivers/net/ppp_generic.c