Merge branch 'dsa-microchip-ptp'

Arun Ramadoss says:

====================
net: dsa: microchip: add PTP support for KSZ9563/KSZ8563 and LAN937x

KSZ9563/KSZ8563 and  LAN937x switch are capable for supporting IEEE 1588 PTP
protocol.  LAN937x has the same PTP register set similar to KSZ9563, hence the
implementation has been made common for the KSZ switches.  KSZ9563 does not
support two step timestamping but LAN937x supports both.  Tested the 1step &
2step p2p timestamping in LAN937x and p2p1step timestamping in KSZ9563.

This patch series is based on the Christian Eggers PTP support for KSZ9563.
Applied the Christian patch and updated as per the latest refactoring of KSZ
series code. The features added on top are PTP packet Interrupt
implementation based on nested handler, LAN937x two step timestamping and
programmable per_out pins.

Link: https://www.spinics.net/lists/netdev/msg705531.html



Patch v7 -> v8
- set skb->ip_summed = CHECKSUM_NONE after updating the checksum

Patch v6 -> v7
- Corrected the misplaced spaces and tabs
- Added mutex lock in do_aux_work
- Replaced 0/1 with false/true for ts_en
- SKB_TX_INPROGRESS flag is set before dsa_enqueue_skb
- Removed the fallthrough keyword
- pdelay_resp header correction is performed based on
  KSZ_SKB_CB(skb)->update_correction instead of clone

Patch v5 -> v6
- Rebased to latest net-next and renamed from RFC to patch net-next.

Patch v4 -> v5
- Replaced irq_domain_add_simple with irq_doamin_add_linear
- Used the helper diff_by_scaled_ppm() for adjfine.

Patch v3 -> v4
- removed IRQF_TRIGGER_FALLING from the request_threaded_irq of ptp msg
- addressed review comments on patch 10 periodic output
- added sign off in patch 6 & 9
- reverted to set PTP_1STEP bit for lan937x which is missed during v3 regression

Patch v2-> v3
- used port_rxtstamp for reconstructing the absolute timestamp instead of
tagger function pointer.
- Reverted to setting of 802.1As bit.

Patch v1 -> v2
- GPIO perout enable bit is different for LAN937x and KSZ9x. Added new patch
for configuring LAN937x programmable pins.
- PTP enabled in hardware based on both tx and rx timestamping of all the user
ports.
- Replaced setting of 802.1AS bit with P2P bit in PTP_MSG_CONF1 register.

RFC v2 -> Patch v1
- Changed the patch author based on past patch submission
- Changed the commit message prefix as net: dsa: microchip: ptp
Individual patch changes are listed in correspondig commits.

RFC v1 -> v2
- Added the p2p1step timestamping and conditional execution of 2 step for
  LAN937x only.
- Added the periodic output support
====================

Signed-off-by: David S. Miller <davem@davemloft.net>