mbox series

[net-next,0/3] Add Possiblity to Reset PHY After Power-up

Message ID 20211214121638.138784-1-philippe.schenker@toradex.com (mailing list archive)
Headers show
Series Add Possiblity to Reset PHY After Power-up | expand

Message

Philippe Schenker Dec. 14, 2021, 12:16 p.m. UTC 
We do have a hardware design in which the ethernet phy regulator and
reset are controlled by software. The ethernet PHY is a Microchip
KSZ9131 [1] and the power sequencing requires a reset after the power
goes up.

In our case the ethernet PHY is connected to a Freescale FEC and the
driver is shutting down the regulator on suspend, however on the resume
path the reset signal is never asserted and because of that the
ethernet is not working anymore.

To solve this adds a new phy_reset_after_power_on() function, similar
to the existing phy_reset_after_clk_enable(), and call it in the fec
resume path after the regulator is switched on as suggested by
Joakim Zhang <qiangqing.zhang@nxp.com>.

[1] https://ww1.microchip.com/downloads/en/DeviceDoc/00002841C.pdf


Philippe Schenker (3):
  net: phy: add phy_reset_after_power_on() function
  net: phy: micrel: add reset-after-power-on flag to ksz9x31 phys
  net: fec: reset phy on resume after power-up

 drivers/net/ethernet/freescale/fec_main.c |  1 +
 drivers/net/phy/micrel.c                  |  2 ++
 drivers/net/phy/phy_device.c              | 24 +++++++++++++++++++++++
 include/linux/phy.h                       |  2 ++
 4 files changed, 29 insertions(+)

Comments

Francesco Dolcini Dec. 14, 2021, 12:23 p.m. UTC | #1 
On Tue, Dec 14, 2021 at 01:16:35PM +0100, Philippe Schenker wrote:
> We do have a hardware design in which the ethernet phy regulator and
> reset are controlled by software. The ethernet PHY is a Microchip
> KSZ9131 [1] and the power sequencing requires a reset after the power
> goes up.
> 
> In our case the ethernet PHY is connected to a Freescale FEC and the
> driver is shutting down the regulator on suspend, however on the resume
> path the reset signal is never asserted and because of that the
> ethernet is not working anymore.
> 
> To solve this adds a new phy_reset_after_power_on() function, similar
> to the existing phy_reset_after_clk_enable(), and call it in the fec
> resume path after the regulator is switched on as suggested by
> Joakim Zhang <qiangqing.zhang@nxp.com>.
> 
> [1] https://ww1.microchip.com/downloads/en/DeviceDoc/00002841C.pdf

For the whole series.

Reviewed-by: Francesco Dolcini <francesco.dolcini@toradex.com>