On Wed, 2011-05-11 at 11:54 +0300, Eliad Peller wrote:
> When WoW is enabled, the interface will stay up and the chip will
> be powered on, so we have to flush/cancel any remaining work, and
> prevent the irq handler from scheduling a new work until the system
> is resumed.
>
> Add 2 new flags:
> * WL1271_FLAG_SUSPENDED - the system is (about to be) suspended.
> * WL1271_FLAG_PENDING_WORK - there is a pending irq work which
> should be scheduled when the system is being resumed.
>
> In order to wake-up the system while getting an irq, we initialize
> the device as wakeup device, and calling pm_wakeup_event() upon
> getting the interrupt (while the system is about to be suspended)
>
> Signed-off-by: Eliad Peller <eliad@xxxxxxxxxx>
> ---
[...]
> diff --git a/drivers/net/wireless/wl12xx/main.c b/drivers/net/wireless/wl12xx/main.c
> index 9ca71ce..308855a 100644
> --- a/drivers/net/wireless/wl12xx/main.c
> +++ b/drivers/net/wireless/wl12xx/main.c
> @@ -1338,6 +1338,28 @@ static int wl1271_op_suspend(struct ieee80211_hw *hw,
> struct wl1271 *wl = hw->priv;
> wl1271_debug(DEBUG_MAC80211, "mac80211 suspend wow=%d", !!wow);
> wl->wow_enabled = !!wow;
> + if (wl->wow_enabled) {
> + /* flush any remaining work */
> + wl1271_debug(DEBUG_MAC80211, "flushing remaining works");
> + flush_delayed_work(&wl->scan_complete_work);
> +
> + /*
> + * disable and re-enable interrupts in order to flush
> + * the threaded_irq
> + */
> + wl1271_disable_interrupts(wl);
> +
> + /*
> + * set suspended flag to avoid triggering a new threaded_irq
> + * work. no need for spinlock as interrupts are disabled.
> + */
> + set_bit(WL1271_FLAG_SUSPENDED, &wl->flags);
The set_bit() function is atomic, so you wouldn't need the spinlock here
anyway. Couldn't you use __set_bit() instead, to avoid the expense of
using an atomic function when it's not necessary?
> +
> + wl1271_enable_interrupts(wl);
> + flush_work(&wl->tx_work);
> + flush_delayed_work(&wl->pspoll_work);
> + flush_delayed_work(&wl->elp_work);
> + }
> return 0;
> }
>
> @@ -1346,6 +1368,30 @@ static int wl1271_op_resume(struct ieee80211_hw *hw)
> struct wl1271 *wl = hw->priv;
> wl1271_debug(DEBUG_MAC80211, "mac80211 resume wow=%d",
> wl->wow_enabled);
> +
> + /*
> + * re-enable irq_work enqueuing, and call irq_work directly if
> + * there is a pending work.
> + */
> + if (wl->wow_enabled) {
> + struct wl1271 *wl = hw->priv;
> + unsigned long flags;
> + bool run_irq_work = false;
> +
> + spin_lock_irqsave(&wl->wl_lock, flags);
> + clear_bit(WL1271_FLAG_SUSPENDED, &wl->flags);
> + if (test_and_clear_bit(WL1271_FLAG_PENDING_WORK, &wl->flags))
> + run_irq_work = true;
> + spin_unlock_irqrestore(&wl->wl_lock, flags);
You could use __clear_bit() and __test_and_clear_bit() here too, since
you're spinning.
> + if (run_irq_work) {
> + wl1271_debug(DEBUG_MAC80211,
> + "run postponed irq_work directly");
> + wl1271_irq(0, wl);
> + wl1271_enable_interrupts(wl);
Shouldn't this wl1271_enable_interrupts() be outside the if? Don't you
want to enable interrupts again when there was no pending work?
> diff --git a/drivers/net/wireless/wl12xx/sdio.c b/drivers/net/wireless/wl12xx/sdio.c
> index 5b03fd5..bf2a6ad 100644
> --- a/drivers/net/wireless/wl12xx/sdio.c
> +++ b/drivers/net/wireless/wl12xx/sdio.c
> @@ -72,6 +72,7 @@ static irqreturn_t wl1271_hardirq(int irq, void *cookie)
> {
> struct wl1271 *wl = cookie;
> unsigned long flags;
> + bool skip = false;
>
> wl1271_debug(DEBUG_IRQ, "IRQ");
>
> @@ -82,8 +83,20 @@ static irqreturn_t wl1271_hardirq(int irq, void *cookie)
> complete(wl->elp_compl);
> wl->elp_compl = NULL;
> }
> +
> + if (test_bit(WL1271_FLAG_SUSPENDED, &wl->flags)) {
> + /* don't enqueue a work right now. mark it as pending */
> + set_bit(WL1271_FLAG_PENDING_WORK, &wl->flags);
> + wl1271_debug(DEBUG_IRQ, "should not enqueue work");
> + disable_irq_nosync(wl->irq);
> + pm_wakeup_event(wl1271_sdio_wl_to_dev(wl), 0);
> + skip = true;
> + }
> spin_unlock_irqrestore(&wl->wl_lock, flags);
>
> + if (skip)
> + return IRQ_HANDLED;
> +
> return IRQ_WAKE_THREAD;
> }
Could be nicer to just skip the skip variable (unintended pun
intended ;). You can do it like this:
if (test_bit...) {
...
spin_unlock_irqrestore();
return IRQ_HANDLED;
}
spin_unlock_irqrestore();
return IRQ_WAKE_THREAD;
Looks a bit nicer to me, but I don't mind if you prefer not skipping the
skip. :)
--
Cheers,
Luca.
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