2016-01-12 13:45:47

by Amitkumar Karwar

Subject: [PATCH] mwifiex: fix power state out of sync problem

From: Shengzhen Li <[email protected]>

It's been observed that driver's power state goes out
of sync with firmware in some corner cases. When this
happens, driver tries to download the data to firmware
assuming it's awake which causes Tx data timeout.

Main thread will process interrupt as soon as interrupt
handler fills 'int_status' variable.

This patch fixes the race issue by updating 'int_status'
at the end of mwifiex_interrupt_status().

Signed-off-by: Shengzhen Li <[email protected]>
Signed-off-by: Amitkumar Karwar <[email protected]>
---
drivers/net/wireless/marvell/mwifiex/pcie.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/net/wireless/marvell/mwifiex/pcie.c b/drivers/net/wireless/marvell/mwifiex/pcie.c
index 5e15464..918e049 100644
--- a/drivers/net/wireless/marvell/mwifiex/pcie.c
+++ b/drivers/net/wireless/marvell/mwifiex/pcie.c
@@ -2116,11 +2116,6 @@ static void mwifiex_interrupt_status(struct mwifiex_adapter *adapter,
}
}

- spin_lock_irqsave(&adapter->int_lock, flags);
- adapter->int_status |= pcie_ireg;
- spin_unlock_irqrestore(&adapter->int_lock, flags);
- mwifiex_dbg(adapter, INTR, "ireg: 0x%08x\n", pcie_ireg);
-
if (!adapter->pps_uapsd_mode &&
adapter->ps_state == PS_STATE_SLEEP &&
mwifiex_pcie_ok_to_access_hw(adapter)) {
@@ -2132,6 +2127,11 @@ static void mwifiex_interrupt_status(struct mwifiex_adapter *adapter,
adapter->pm_wakeup_fw_try = false;
del_timer(&adapter->wakeup_timer);
}
+
+ spin_lock_irqsave(&adapter->int_lock, flags);
+ adapter->int_status |= pcie_ireg;
+ spin_unlock_irqrestore(&adapter->int_lock, flags);
+ mwifiex_dbg(adapter, INTR, "ireg: 0x%08x\n", pcie_ireg);
}

/*
--
1.8.1.4

2016-01-29 09:18:47

by Kalle Valo

Subject: Re: mwifiex: fix power state out of sync problem

> From: Shengzhen Li <[email protected]>
>
> It's been observed that driver's power state goes out
> of sync with firmware in some corner cases. When this
> happens, driver tries to download the data to firmware
> assuming it's awake which causes Tx data timeout.
>
> Main thread will process interrupt as soon as interrupt
> handler fills 'int_status' variable.
>
> This patch fixes the race issue by updating 'int_status'
> at the end of mwifiex_interrupt_status().
>
> Signed-off-by: Shengzhen Li <[email protected]>
> Signed-off-by: Amitkumar Karwar <[email protected]>

Thanks, applied to wireless-drivers-next.git.

Kalle Valo