From 7f822999e12a144e68c915194267108f8051cf9b Mon Sep 17 00:00:00 2001
From: Yinghai Lu <yinghai@kernel.org>
Date: Fri, 27 Jan 2012 10:55:14 -0800
Subject: [PATCH] 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>
---
drivers/pci/hotplug/pciehp_hpc.c | 36 ++++++++++++++++++++++++++++++++
1 file changed, 36 insertions(+)
diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c
index 4ebdc1de2cb4d..db33688af5888 100644
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -352,6 +352,42 @@ int pciehp_check_link_status(struct controller *ctrl)
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;
--
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