diff options
author | Ben Hutchings <bhutchings@solarflare.com> | 2009-01-29 17:49:29 +0000 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2009-01-30 14:06:29 -0800 |
commit | 2f08575389ac37ece5922094777442d8fdd8c00a (patch) | |
tree | bb2be0550b3b6f669257295f4ba1ad754c4f39d0 | |
parent | 8b9dc8dd447cfe27c0214761ced22a8e4aa58f5e (diff) | |
download | talos-obmc-linux-2f08575389ac37ece5922094777442d8fdd8c00a.tar.gz talos-obmc-linux-2f08575389ac37ece5922094777442d8fdd8c00a.zip |
sfc: SFN4111T: Fix GPIO sharing between I2C and FLASH_CFG_1
Change sfn4111t_reset() to change only GPIO output enables so that it
doesn't break subsequent I2C operations.
Update comments to explain exactly what we're doing.
Add a short sleep to make sure the FLASH_CFG_1 value is latched before
any subsequent I2C operations.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r-- | drivers/net/sfc/sfe4001.c | 15 |
1 files changed, 9 insertions, 6 deletions
diff --git a/drivers/net/sfc/sfe4001.c b/drivers/net/sfc/sfe4001.c index 16b80acb9992..c7c95db2af6d 100644 --- a/drivers/net/sfc/sfe4001.c +++ b/drivers/net/sfc/sfe4001.c @@ -186,19 +186,22 @@ static int sfn4111t_reset(struct efx_nic *efx) { efx_oword_t reg; - /* GPIO pins are also used for I2C, so block that temporarily */ + /* GPIO 3 and the GPIO register are shared with I2C, so block that */ mutex_lock(&efx->i2c_adap.bus_lock); + /* Pull RST_N (GPIO 2) low then let it up again, setting the + * FLASH_CFG_1 strap (GPIO 3) appropriately. Only change the + * output enables; the output levels should always be 0 (low) + * and we rely on external pull-ups. */ falcon_read(efx, ®, GPIO_CTL_REG_KER); EFX_SET_OWORD_FIELD(reg, GPIO2_OEN, true); - EFX_SET_OWORD_FIELD(reg, GPIO2_OUT, false); falcon_write(efx, ®, GPIO_CTL_REG_KER); msleep(1000); - EFX_SET_OWORD_FIELD(reg, GPIO2_OUT, true); - EFX_SET_OWORD_FIELD(reg, GPIO3_OEN, true); - EFX_SET_OWORD_FIELD(reg, GPIO3_OUT, - !(efx->phy_mode & PHY_MODE_SPECIAL)); + EFX_SET_OWORD_FIELD(reg, GPIO2_OEN, false); + EFX_SET_OWORD_FIELD(reg, GPIO3_OEN, + !!(efx->phy_mode & PHY_MODE_SPECIAL)); falcon_write(efx, ®, GPIO_CTL_REG_KER); + msleep(1); mutex_unlock(&efx->i2c_adap.bus_lock); |