mfd: dln2: Use irqsave() in USB's complete callback (50d44f82) · Commits · 戴 / test

The USB completion callback does not disable interrupts while acquiring the lock. We want to remove the local_irq_disable() invocation from __usb_hcd_giveback_urb() and therefore it is required for the callback handler to disable the interrupts while acquiring the lock. The callback may be invoked either in IRQ or BH context depending on the USB host controller. Use the _irqsave() variant of the locking primitives. Reviewed-by:

Johan Hovold <johan@kernel.org> Signed-off-by:

Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by:

Lee Jones <lee.jones@linaro.org>

drivers/mfd/dln2.c

+3 −7

Original line number	Diff line number	Diff line
		@@ -194,6 +194,7 @@ static bool dln2_transfer_complete(struct dln2_dev dln2, struct urb urb,
		struct device *dev = &dln2->interface->dev;
		struct dln2_mod_rx_slots *rxs = &dln2->mod_rx_slots[handle];
		struct dln2_rx_context *rxc;
		unsigned long flags;
		bool valid_slot = false;

		if (rx_slot >= DLN2_MAX_RX_SLOTS)
		@@ -201,18 +202,13 @@ static bool dln2_transfer_complete(struct dln2_dev dln2, struct urb urb,

		rxc = &rxs->slots[rx_slot];

		/*
		* No need to disable interrupts as this lock is not taken in interrupt
		* context elsewhere in this driver. This function (or its callers) are
		* also not exported to other modules.
		*/
		spin_lock(&rxs->lock);
		spin_lock_irqsave(&rxs->lock, flags);
		if (rxc->in_use && !rxc->urb) {
		rxc->urb = urb;
		complete(&rxc->done);
		valid_slot = true;
		}
		spin_unlock(&rxs->lock);
		spin_unlock_irqrestore(&rxs->lock, flags);

		out:
		if (!valid_slot)

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