[RESEND PATCH v5 3/9] PCI: endpoint: Warn and return if EPC is started/stopped multiple times

[Manivannan Sadhasivam]

When the EPC is started or stopped multiple times from configfs, just emit
a once time warning and return. There is no need to call the EPC start/stop
functions in those cases.

Reviewed-by: Kishon Vijay Abraham I <kishon@xxxxxxxxxx>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
---
 drivers/pci/endpoint/pci-ep-cfs.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/pci/endpoint/pci-ep-cfs.c b/drivers/pci/endpoint/pci-ep-cfs.c
index 4b8ac0ac84d5..62c8e09c59f4 100644
--- a/drivers/pci/endpoint/pci-ep-cfs.c
+++ b/drivers/pci/endpoint/pci-ep-cfs.c
@@ -178,6 +178,9 @@ static ssize_t pci_epc_start_store(struct config_item *item, const char *page,
 	if (kstrtobool(page, &start) < 0)
 		return -EINVAL;
 
+	if (WARN_ON_ONCE(start == epc_group->start))
+		return 0;
+
 	if (!start) {
 		pci_epc_stop(epc);
 		epc_group->start = 0;
-- 
2.25.1