mirror_ubuntu-kernels/drivers/net/dsa
Tobias Jakobi (Compleo) b7fb7729c9 net: dsa: microchip: fix register write order in ksz8_ind_write8()
This bug was noticed while re-implementing parts of the kernel
driver in userspace using spidev. The goal was to enable some
of the errata workarounds that Microchip describes in their
errata sheet [1].

Both the errata sheet and the regular datasheet of e.g. the KSZ8795
imply that you need to do this for indirect register accesses:
- write a 16-bit value to a control register pair (this value
  consists of the indirect register table, and the offset inside
  the table)
- either read or write an 8-bit value from the data storage
  register (indicated by REG_IND_BYTE in the kernel)

The current implementation has the order swapped. It can be
proven, by reading back some indirect register with known content
(the EEE register modified in ksz8_handle_global_errata() is one of
these), that this implementation does not work.

Private discussion with Oleksij Rempel of Pengutronix has revealed
that the workaround was apparantly never tested on actual hardware.

[1] https://ww1.microchip.com/downloads/aemDocuments/documents/OTH/ProductDocuments/Errata/KSZ87xx-Errata-DS80000687C.pdf

Signed-off-by: Tobias Jakobi (Compleo) <tobias.jakobi.compleo@gmail.com>
Reviewed-by: Oleksij Rempel <o.rempel@pengutronix.de>
Fixes: 7b6e6235b6 ("net: dsa: microchip: ksz8795: handle eee specif erratum")
Link: https://lore.kernel.org/r/20240304154135.161332-1-tobias.jakobi.compleo@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-03-05 19:10:49 -08:00
..
b53 net: dsa: Use conduit and user terms 2023-10-24 13:08:14 -07:00
hirschmann net: dsa: hirschmann: Convert to platform remove callback returning void 2023-09-20 10:25:57 +01:00
microchip net: dsa: microchip: fix register write order in ksz8_ind_write8() 2024-03-05 19:10:49 -08:00
mv88e6xxx net: dsa: mv88e6xxx: Fix failed probe due to unsupported C45 reads 2024-01-31 15:57:07 -08:00
ocelot net: dsa: Use conduit and user terms 2023-10-24 13:08:14 -07:00
qca net: dsa: qca8k: fix illegal usage of GPIO 2024-01-29 18:14:07 -08:00
realtek net: dsa: realtek: Rewrite RTL8366RB MTU handling 2023-12-12 14:17:06 +01:00
sja1105 net: dsa: sja1105: Use units.h instead of the copy of a definition 2023-11-29 20:12:17 -08:00
xrs700x net: dsa: Use conduit and user terms 2023-10-24 13:08:14 -07:00
bcm_sf2_cfp.c net: dsa: Use conduit and user terms 2023-10-24 13:08:14 -07:00
bcm_sf2_regs.h net: dsa: bcm_sf2: refactor LED regs access 2021-12-30 17:28:32 -08:00
bcm_sf2.c net: dsa: bcm_sf2: drop priv->master_mii_dn 2024-01-05 11:56:36 +00:00
bcm_sf2.h net: dsa: bcm_sf2: drop priv->master_mii_dn 2024-01-05 11:56:36 +00:00
dsa_loop_bdinfo.c net: fill in MODULE_DESCRIPTION()s for dsa_loop_bdinfo 2024-02-09 14:12:02 -08:00
dsa_loop.c net: dsa: dsa_loop: add phylink capabilities 2023-10-11 10:06:05 +01:00
dsa_loop.h
Kconfig net: dsa: mt7530: improve and relax PHY driver dependency 2023-08-09 11:22:55 +01:00
lan9303_i2c.c net: dsa: Switch i2c drivers back to use .probe() 2023-05-31 09:52:55 +01:00
lan9303_mdio.c net: dsa: lan9303: consequently nested-lock physical MDIO 2023-11-02 10:48:09 +01:00
lan9303-core.c net: dsa: Use conduit and user terms 2023-10-24 13:08:14 -07:00
lan9303.h
lantiq_gswip.c net: dsa: lantiq_gswip: ignore MDIO buses disabled in OF 2024-01-05 11:56:35 +00:00
lantiq_pce.h
Makefile net: dsa: mt7530: introduce driver for MT7988 built-in switch 2023-04-03 10:13:01 +01:00
mt7530-mdio.c net: dsa: mt7530: fix support for MT7531BE 2023-04-19 17:37:45 -07:00
mt7530-mmio.c net: dsa: mt7530: Convert to platform remove callback returning void 2023-09-20 10:25:57 +01:00
mt7530.c net: dsa: mt7530: fix 10M/100M speed on MT7988 switch 2024-01-26 14:18:39 -08:00
mt7530.h net: dsa: mt7530: fix handling of 802.1X PAE frames 2023-08-19 12:29:33 +01:00
mv88e6060.c net: dsa: mv88e6060: add phylink_get_caps implementation 2023-08-14 18:57:17 -07:00
mv88e6060.h
rzn1_a5psw.c net: dsa: rzn1_a5psw: Convert to platform remove callback returning void 2023-09-20 10:25:58 +01:00
rzn1_a5psw.h net: dsa: rzn1-a5psw: add vlan support 2023-08-11 11:58:36 +01:00
vitesse-vsc73xx-core.c net: dsa: vsc73xx: Add null pointer check to vsc73xx_gpio_probe 2024-01-16 17:48:27 -08:00
vitesse-vsc73xx-platform.c net: dsa: vitesse-vsc73xx: Convert to platform remove callback returning void 2023-09-20 10:25:58 +01:00
vitesse-vsc73xx-spi.c net: dsa: vitesse-vsc73xx: remove unnecessary set_drvdata() 2022-09-22 19:30:39 -07:00
vitesse-vsc73xx.h net: dsa: vsc73xxx: Make vsc73xx_remove() return void 2021-11-15 13:15:07 +00:00