Commit 44af146a authored May 04, 2013 by Matthew Wilcox

NVMe: Only clear the enable bit when disabling controller



Many of the bits in the Controller Configuration register may only be
modified when the Enable bit is clear.  Clearing them at the same time
as the Enable bit might be OK, but let's play it safe and only touch the
Enable bit.

Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>

parent ba47e386

drivers/block/nvme-core.c

+4 −1

Original line number	Diff line number	Diff line
		@@ -1137,7 +1137,10 @@ static int nvme_wait_ready(struct nvme_dev *dev, u64 cap, bool enabled)
		*/
		static int nvme_disable_ctrl(struct nvme_dev *dev, u64 cap)
		{
		writel(0, &dev->bar->cc);
		u32 cc = readl(&dev->bar->cc);

		if (cc & NVME_CC_ENABLE)
		writel(cc & ~NVME_CC_ENABLE, &dev->bar->cc);
		return nvme_wait_ready(dev, cap, false);
		}