Message ID | 1238087676-14194-1-git-send-email-steve.glendinning@smsc.com |
---|---|
State | Accepted, archived |
Delegated to: | David Miller |
Headers | show |
From: Steve Glendinning <steve.glendinning@smsc.com> Date: Thu, 26 Mar 2009 17:14:36 +0000 > The LAN911x datasheet specifies a minimum delay of 45ns between a write > of E2P_DATA and any read. This patch adds a single dummy read of > BYTE_TEST to enforce this timing constraint. > > Signed-off-by: Steve Glendinning <steve.glendinning@smsc.com> Applied. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/net/smsc911x.c b/drivers/net/smsc911x.c index ad3cbc9..af8f60c 100644 --- a/drivers/net/smsc911x.c +++ b/drivers/net/smsc911x.c @@ -1680,6 +1680,7 @@ static int smsc911x_eeprom_write_location(struct smsc911x_data *pdata, u8 address, u8 data) { u32 op = E2P_CMD_EPC_CMD_ERASE_ | address; + u32 temp; int ret; SMSC_TRACE(DRV, "address 0x%x, data 0x%x", address, data); @@ -1688,6 +1689,10 @@ static int smsc911x_eeprom_write_location(struct smsc911x_data *pdata, if (!ret) { op = E2P_CMD_EPC_CMD_WRITE_ | address; smsc911x_reg_write(pdata, E2P_DATA, (u32)data); + + /* Workaround for hardware read-after-write restriction */ + temp = smsc911x_reg_read(pdata, BYTE_TEST); + ret = smsc911x_eeprom_send_cmd(pdata, op); }
The LAN911x datasheet specifies a minimum delay of 45ns between a write of E2P_DATA and any read. This patch adds a single dummy read of BYTE_TEST to enforce this timing constraint. Signed-off-by: Steve Glendinning <steve.glendinning@smsc.com> --- drivers/net/smsc911x.c | 5 +++++ 1 files changed, 5 insertions(+), 0 deletions(-)