diff options
| author | Emmanuel Grumbach <emmanuel.grumbach@intel.com> | 2014-10-27 10:14:32 +0300 |
|---|---|---|
| committer | Emmanuel Grumbach <emmanuel.grumbach@intel.com> | 2014-11-11 18:15:09 +0300 |
| commit | 01e58a281e6f0184e54af19a74de9a4012eeab25 (patch) | |
| tree | bcaf81be55e67d2e2e39dbf48e5faabcdc168ac6 /drivers/net/wireless/iwlwifi/pcie/tx.c | |
| parent | ea9af24d03a905143544ba383e23c731ba3bc5bd (diff) | |
| download | linux-01e58a281e6f0184e54af19a74de9a4012eeab25.tar.xz | |
iwlwifi: pcie: introduce delay when waking up the device
In some rare cases, the firmware can put the device to
sleep after the driver requested the access. This is
because the access request can take a short time to be
propagated to the firmware.
If that happens, the driver may think that it has access
since the firmware hasn't put the device to sleep yet, but
right after the driver's check, the firmware might put the
device to sleep.
Warn when this happens by allowing the firmware to finish
the "put the device sleep" flow so that the driver will
not get access to the device. This will make the issue
visible.
This still doesn't fix the race, but at least it makes
it more visible.
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Diffstat (limited to 'drivers/net/wireless/iwlwifi/pcie/tx.c')
| -rw-r--r-- | drivers/net/wireless/iwlwifi/pcie/tx.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/net/wireless/iwlwifi/pcie/tx.c b/drivers/net/wireless/iwlwifi/pcie/tx.c index eb8e2984c5e9..4a4104eda9b8 100644 --- a/drivers/net/wireless/iwlwifi/pcie/tx.c +++ b/drivers/net/wireless/iwlwifi/pcie/tx.c @@ -1431,6 +1431,9 @@ static int iwl_pcie_enqueue_hcmd(struct iwl_trans *trans, trans_pcie->cmd_in_flight = true; __iwl_trans_pcie_set_bit(trans, CSR_GP_CNTRL, CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ); + if (trans->cfg->device_family == IWL_DEVICE_FAMILY_8000) + udelay(2); + ret = iwl_poll_bit(trans, CSR_GP_CNTRL, CSR_GP_CNTRL_REG_VAL_MAC_ACCESS_EN, (CSR_GP_CNTRL_REG_FLAG_MAC_CLOCK_READY | |