From 73a92ae5a99047632c31f0fd592da79eb8d05144 Mon Sep 17 00:00:00 2001 From: Ethan Nelson-Moore Date: Mon, 2 Feb 2026 17:39:09 -0800 Subject: [PATCH] net: usb: sr9700: remove code to drive nonexistent multicast filter [ Upstream commit 9a9424c756feee9ee6e717405a9d6fa7bacdef08 ] Several registers referenced in this driver's source code do not actually exist (they are not writable and read as zero in my testing). They exist in this driver because it originated as a copy of the dm9601 driver. Notably, these include the multicast filter registers - this causes the driver to not support multicast packets correctly. Remove the multicast filter code and register definitions. Instead, set the chip to receive all multicast filter packets when any multicast addresses are in the list. Reviewed-by: Simon Horman (from v1) Signed-off-by: Ethan Nelson-Moore Link: https://patch.msgid.link/20260203013924.28582-1-enelsonmoore@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/usb/Kconfig | 1 - drivers/net/usb/sr9700.c | 25 ++++--------------------- drivers/net/usb/sr9700.h | 7 +------ 3 files changed, 5 insertions(+), 28 deletions(-) diff --git a/drivers/net/usb/Kconfig b/drivers/net/usb/Kconfig index 3c360d4f0635..73498a3ea44c 100644 --- a/drivers/net/usb/Kconfig +++ b/drivers/net/usb/Kconfig @@ -321,7 +321,6 @@ config USB_NET_DM9601 config USB_NET_SR9700 tristate "CoreChip-sz SR9700 based USB 1.1 10/100 ethernet devices" depends on USB_USBNET - select CRC32 help This option adds support for CoreChip-sz SR9700 based USB 1.1 10/100 Ethernet adapters. diff --git a/drivers/net/usb/sr9700.c b/drivers/net/usb/sr9700.c index 213b4817cfdf..e4d7bcd0d99c 100644 --- a/drivers/net/usb/sr9700.c +++ b/drivers/net/usb/sr9700.c @@ -18,7 +18,6 @@ #include #include #include -#include #include #include "sr9700.h" @@ -265,31 +264,15 @@ static const struct ethtool_ops sr9700_ethtool_ops = { static void sr9700_set_multicast(struct net_device *netdev) { struct usbnet *dev = netdev_priv(netdev); - /* We use the 20 byte dev->data for our 8 byte filter buffer - * to avoid allocating memory that is tricky to free later - */ - u8 *hashes = (u8 *)&dev->data; /* rx_ctl setting : enable, disable_long, disable_crc */ u8 rx_ctl = RCR_RXEN | RCR_DIS_CRC | RCR_DIS_LONG; - memset(hashes, 0x00, SR_MCAST_SIZE); - /* broadcast address */ - hashes[SR_MCAST_SIZE - 1] |= SR_MCAST_ADDR_FLAG; - if (netdev->flags & IFF_PROMISC) { + if (netdev->flags & IFF_PROMISC) rx_ctl |= RCR_PRMSC; - } else if (netdev->flags & IFF_ALLMULTI || - netdev_mc_count(netdev) > SR_MCAST_MAX) { - rx_ctl |= RCR_RUNT; - } else if (!netdev_mc_empty(netdev)) { - struct netdev_hw_addr *ha; + else if (netdev->flags & IFF_ALLMULTI || !netdev_mc_empty(netdev)) + /* The chip has no multicast filter */ + rx_ctl |= RCR_ALL; - netdev_for_each_mc_addr(ha, netdev) { - u32 crc = ether_crc(ETH_ALEN, ha->addr) >> 26; - hashes[crc >> 3] |= 1 << (crc & 0x7); - } - } - - sr_write_async(dev, SR_MAR, SR_MCAST_SIZE, hashes); sr_write_reg_async(dev, SR_RCR, rx_ctl); } diff --git a/drivers/net/usb/sr9700.h b/drivers/net/usb/sr9700.h index ea2b4de621c8..c479908f7d82 100644 --- a/drivers/net/usb/sr9700.h +++ b/drivers/net/usb/sr9700.h @@ -104,9 +104,7 @@ #define WCR_LINKEN (1 << 5) /* Physical Address Reg */ #define SR_PAR 0x10 /* 0x10 ~ 0x15 6 bytes for PAR */ -/* Multicast Address Reg */ -#define SR_MAR 0x16 /* 0x16 ~ 0x1D 8 bytes for MAR */ -/* 0x1e unused */ +/* 0x16 --> 0x1E unused */ /* Phy Reset Reg */ #define SR_PRR 0x1F #define PRR_PHY_RST (1 << 0) @@ -161,9 +159,6 @@ /* parameters */ #define SR_SHARE_TIMEOUT 1000 #define SR_EEPROM_LEN 256 -#define SR_MCAST_SIZE 8 -#define SR_MCAST_ADDR_FLAG 0x80 -#define SR_MCAST_MAX 64 #define SR_TX_OVERHEAD 2 /* 2bytes header */ #define SR_RX_OVERHEAD 7 /* 3bytes header + 4crc tail */