The RTL8153-AD supports a persistent system specific MAC address. This means a device plugged into two different systems with host side support will show different (but persistent) MAC addresses.
This information for the system's persistent MAC address is burned in when the system HW is built and available under _SB\AMAC in the DSDT at runtime. This technology is currently implemented in the Dell TB15 and WD15 Type-C docks. More information is available here: http://www.dell.com/support/article/us/en/04/SLN301147 Signed-off-by: Mario Limonciello <mario_limoncie...@dell.com> --- Changes from v3: * Add additional comments about functions and what they're doing * Adjust warning calls to use netif instead * Rename function drivers/net/usb/r8152.c | 70 +++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 68 insertions(+), 2 deletions(-) diff --git a/drivers/net/usb/r8152.c b/drivers/net/usb/r8152.c index 3f9f6ed..b2339d3 100644 --- a/drivers/net/usb/r8152.c +++ b/drivers/net/usb/r8152.c @@ -26,6 +26,7 @@ #include <linux/mdio.h> #include <linux/usb/cdc.h> #include <linux/suspend.h> +#include <linux/acpi.h> /* Information for net-next */ #define NETNEXT_VERSION "08" @@ -455,6 +456,11 @@ /* SRAM_IMPEDANCE */ #define RX_DRIVING_MASK 0x6000 +/* MAC PASSTHRU */ +#define AD_MASK 0xfee0 +#define EFUSE 0xcfdb +#define PASS_THRU_MASK 0x1 + enum rtl_register_content { _1000bps = 0x10, _100bps = 0x08, @@ -1030,6 +1036,59 @@ out1: return ret; } +/* Devices containing RTL8153-AD can support a persistent + * host system provided MAC address. + * Examples of this are Dell TB15 and Dell WD15 docks + */ +static int get_vendor_mac_passthru_addr(struct r8152 *tp, struct sockaddr *sa) +{ + acpi_status status; + struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; + union acpi_object *obj; + int ret = -EINVAL; + u32 ocp_data; + unsigned char buf[6]; + + /* test for -AD variant of RTL8153 */ + ocp_data = ocp_read_word(tp, MCU_TYPE_USB, USB_MISC_0); + if ((ocp_data & AD_MASK) != 0x1000) + return -ENODEV; + + /* test for MAC address pass-through bit */ + ocp_data = ocp_read_byte(tp, MCU_TYPE_USB, EFUSE); + if ((ocp_data & PASS_THRU_MASK) != 1) + return -ENODEV; + + /* returns _AUXMAC_#AABBCCDDEEFF# */ + status = acpi_evaluate_object(NULL, "\\_SB.AMAC", NULL, &buffer); + obj = (union acpi_object *)buffer.pointer; + if (ACPI_SUCCESS(status)) { + if (obj->type != ACPI_TYPE_BUFFER || + obj->string.length != 0x17) { + netif_warn(tp, probe, tp->netdev, "Invalid buffer\n"); + goto amacout; + } + if (strncmp(obj->string.pointer, "_AUXMAC_#", 9) != 0) { + netif_warn(tp, probe, tp->netdev, "Invalid header\n"); + goto amacout; + } + ret = hex2bin(buf, obj->string.pointer + 9, 6); + if (ret < 0 || !is_valid_ether_addr(buf)) { + netif_warn(tp, probe, tp->netdev, "Invalid MAC\n"); + goto amacout; + } + memcpy(sa->sa_data, buf, 6); + ether_addr_copy(tp->netdev->dev_addr, sa->sa_data); + netif_info(tp, probe, tp->netdev, + "Using pass-through MAC addr %pM\n", sa->sa_data); + ret = 0; + } + +amacout: + kfree(obj); + return ret; +} + static int set_ethernet_addr(struct r8152 *tp) { struct net_device *dev = tp->netdev; @@ -1038,8 +1097,15 @@ static int set_ethernet_addr(struct r8152 *tp) if (tp->version == RTL_VER_01) ret = pla_ocp_read(tp, PLA_IDR, 8, sa.sa_data); - else - ret = pla_ocp_read(tp, PLA_BACKUP, 8, sa.sa_data); + else { + /* if this is not an RTL8153-AD, no eFuse mac pass thru set, + * or system doesn't provide valid _SB.AMAC this will be + * be expected to non-zero + */ + ret = get_vendor_mac_passthru_addr(tp, &sa); + if (ret < 0) + ret = pla_ocp_read(tp, PLA_BACKUP, 8, sa.sa_data); + } if (ret < 0) { netif_err(tp, probe, dev, "Get ether addr fail\n"); -- 2.7.4
