Re: [PATCH net] net: dsa: microchip: Fix KSZ8863 reset problem
From: Oleksij Rempel <o.rempel@pengutronix.de>
Date: 2025-08-02 18:59:55
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Hi, On Fri, Aug 01, 2025 at 05:22:53PM -0700, Tristram.Ha@microchip.com wrote:
From: Tristram Ha <redacted> ksz8873_valid_regs[] was added for register access for KSZ8863/KSZ8873 switches, but the reset register is not in the list so ksz8_reset_switch() does not take any effect. ksz_cfg() is updated to display an error so that there will be a future check for adding new register access code. A side effect of not resetting the switch is the static MAC table is not cleared. Further additions to the table will show write error as there are only 8 entries in the table.
Thank you for fixing it!
quoted hunk ↗ jump to hunk
Fixes: d0dec3333040 ("net: dsa: microchip: Add register access control for KSZ8873 chip") Signed-off-by: Tristram Ha <redacted> --- drivers/net/dsa/microchip/ksz8.c | 7 ++++++- drivers/net/dsa/microchip/ksz_common.c | 1 + 2 files changed, 7 insertions(+), 1 deletion(-)diff --git a/drivers/net/dsa/microchip/ksz8.c b/drivers/net/dsa/microchip/ksz8.c index 76e490070e9c..6d282a8e3684 100644 --- a/drivers/net/dsa/microchip/ksz8.c +++ b/drivers/net/dsa/microchip/ksz8.c@@ -36,7 +36,12 @@ static void ksz_cfg(struct ksz_device *dev, u32 addr, u8 bits, bool set) { - regmap_update_bits(ksz_regmap_8(dev), addr, bits, set ? bits : 0); + int ret; + + ret = regmap_update_bits(ksz_regmap_8(dev), addr, bits, set ? bits : 0); + if (ret) + dev_err(dev->dev, "can't update reg 0x%x: %pe\n", addr, + ERR_PTR(ret));
Better using ksz_rmw8() instead. It is already providing error message. In this file there is 4 direct accesses to regmap_update_bits() without error handling. It would be great if you have chance to replace it with ksz_rmw8() too.
quoted hunk ↗ jump to hunk
} static void ksz_port_cfg(struct ksz_device *dev, int port, int offset, u8 bits,diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c index 7292bfe2f7ca..4cb14288ff0f 100644 --- a/drivers/net/dsa/microchip/ksz_common.c +++ b/drivers/net/dsa/microchip/ksz_common.c@@ -1447,6 +1447,7 @@ static const struct regmap_range ksz8873_valid_regs[] = { regmap_reg_range(0x3f, 0x3f), /* advanced control registers */ + regmap_reg_range(0x43, 0x43),
This register is no documented in the public documentation. Out of curiosity, are there some where more information about this two "reserved" register ranges: 0x3A-0x3E and 0x40-0x5F? Best regards, Oleksij -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |