PCI: pciehp: Add Disable/enable link functions
Will use it during power off/on of slots
Signed-off-by: Yinghai Lu <yinghai.lu@oracle.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c
index 4ebdc1d..db33688 100644
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -352,6 +352,42 @@
return retval;
}
+static int __pciehp_link_set(struct controller *ctrl, bool enable)
+{
+ u16 lnk_ctrl;
+ int retval = 0;
+
+ retval = pciehp_readw(ctrl, PCI_EXP_LNKCTL, &lnk_ctrl);
+ if (retval) {
+ ctrl_err(ctrl, "Cannot read LNKCTRL register\n");
+ return retval;
+ }
+
+ if (enable)
+ lnk_ctrl &= ~PCI_EXP_LNKCTL_LD;
+ else
+ lnk_ctrl |= PCI_EXP_LNKCTL_LD;
+
+ retval = pciehp_writew(ctrl, PCI_EXP_LNKCTL, lnk_ctrl);
+ if (retval) {
+ ctrl_err(ctrl, "Cannot write LNKCTRL register\n");
+ return retval;
+ }
+ ctrl_dbg(ctrl, "%s: lnk_ctrl = %x\n", __func__, lnk_ctrl);
+
+ return retval;
+}
+
+static int pciehp_link_enable(struct controller *ctrl)
+{
+ return __pciehp_link_set(ctrl, true);
+}
+
+static int pciehp_link_disable(struct controller *ctrl)
+{
+ return __pciehp_link_set(ctrl, false);
+}
+
int pciehp_get_attention_status(struct slot *slot, u8 *status)
{
struct controller *ctrl = slot->ctrl;