Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 36b9010f authored by Tony Truong's avatar Tony Truong Committed by Gerrit - the friendly Code Review server
Browse files

msm: pcie: add mutex for PCIe enumeration 



PCIe bus driver supports a few ways for clients to
trigger enumeration. To prevent race conditions,
add a mutex to secure the enumeration process.

Change-Id: Ifa4f6d2b4edee85e750e6e44626c89ec0de966cf
Signed-off-by: default avatarTony Truong <truong@codeaurora.org>
parent 83f579a0

drivers/pci/host/pci-msm.c

+16 −7
Original line number Diff line number Diff line
@@ -591,6 +591,7 @@ struct msm_pcie_dev_t { 
	bool				 cfg_access;

	spinlock_t			 cfg_lock;

	unsigned long		    irqsave_flags;

	struct mutex			enumerate_lock;

	struct mutex		     setup_lock;



	struct irq_domain		*irq_domain;
@@ -4840,12 +4841,15 @@ int msm_pcie_enumerate(u32 rc_idx) 
	int ret = 0, bus_ret = 0, scan_ret = 0;

	struct msm_pcie_dev_t *dev = &msm_pcie_dev[rc_idx];



	mutex_lock(&dev->enumerate_lock);



	PCIE_DBG(dev, "Enumerate RC%d\n", rc_idx);



	if (!dev->drv_ready) {

		PCIE_DBG(dev, "RC%d has not been successfully probed yet\n",

			rc_idx);

		return -EPROBE_DEFER;

		ret = -EPROBE_DEFER;

		goto out;

	}



	if (!dev->enumerated) {
@@ -4872,8 +4876,7 @@ int msm_pcie_enumerate(u32 rc_idx) 
				PCIE_ERR(dev,

					"PCIe: failed to get host bridge resources for RC%d: %d\n",

					dev->rc_idx, ret);



				return ret;

				goto out;

			}



			if (dev->ep_latency) {
@@ -4892,8 +4895,8 @@ int msm_pcie_enumerate(u32 rc_idx) 
				PCIE_ERR(dev,

					"PCIe: failed to create root bus for RC%d\n",

					dev->rc_idx);



				return -ENOMEM;

				ret = -ENOMEM;

				goto out;

			}



			scan_ret = pci_scan_child_bus(bus);
@@ -4941,7 +4944,8 @@ int msm_pcie_enumerate(u32 rc_idx) 
				PCIE_ERR(dev,

					"PCIe: Did not find PCI device for RC%d.\n",

					dev->rc_idx);

				return -ENODEV;

				ret = -ENODEV;

				goto out;

			}



			bus_ret = bus_for_each_dev(&pci_bus_type, NULL, dev,
@@ -4951,7 +4955,8 @@ int msm_pcie_enumerate(u32 rc_idx) 
				PCIE_ERR(dev,

					"PCIe: Failed to set up device table for RC%d\n",

					dev->rc_idx);

				return -ENODEV;

				ret = -ENODEV;

				goto out;

			}

		} else {

			PCIE_ERR(dev, "PCIe: failed to enable RC%d.\n",
@@ -4962,6 +4967,9 @@ int msm_pcie_enumerate(u32 rc_idx) 
			dev->rc_idx);

	}



out:

	mutex_unlock(&dev->enumerate_lock);



	return ret;

}

EXPORT_SYMBOL(msm_pcie_enumerate);
@@ -6303,6 +6311,7 @@ int __init pcie_init(void) 
				rc_name, i);

		spin_lock_init(&msm_pcie_dev[i].cfg_lock);

		msm_pcie_dev[i].cfg_access = true;

		mutex_init(&msm_pcie_dev[i].enumerate_lock);

		mutex_init(&msm_pcie_dev[i].setup_lock);

		mutex_init(&msm_pcie_dev[i].recovery_lock);

		spin_lock_init(&msm_pcie_dev[i].linkdown_lock);