PCIEHP: Add Electro Mechanical Interlock (EMI) support to the PCIE hotplug driver.

Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 55 insertions, 0 deletions

diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c
index eb1862b50bb1..fbc64aa2dd68 100644
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -35,6 +35,7 @@
 #include <linux/timer.h>
 #include <linux/pci.h>
 #include <linux/interrupt.h>
+#include <linux/time.h>
 
 #include "../pci.h"
 #include "pciehp.h"
@@ -192,6 +193,7 @@ static inline int pciehp_writel(struct controller *ctrl, int reg, u32 value)
 #define ATTN_LED_CTRL                   0x00C0
 #define PWR_LED_CTRL                    0x0300
 #define PWR_CTRL                        0x0400
+#define EMI_CTRL                        0x0800
 
 /* Attention indicator and Power indicator states */
 #define LED_ON          0x01
@@ -202,6 +204,10 @@ static inline int pciehp_writel(struct controller *ctrl, int reg, u32 value)
 #define POWER_ON        0
 #define POWER_OFF       0x0400
 
+/* EMI Status defines */
+#define EMI_DISENGAGED  0
+#define EMI_ENGAGED     1
+
 /* Field definitions in Slot Status Register */
 #define ATTN_BUTTN_PRESSED      0x0001
 #define PWR_FAULT_DETECTED      0x0002
@@ -210,6 +216,8 @@ static inline int pciehp_writel(struct controller *ctrl, int reg, u32 value)
 #define CMD_COMPLETED           0x0010
 #define MRL_STATE               0x0020
 #define PRSN_STATE              0x0040
+#define EMI_STATE               0x0080
+#define EMI_STATUS_BIT          7
 
 static spinlock_t hpc_event_lock;
 
@@ -474,6 +482,51 @@ static int hpc_query_power_fault(struct slot *slot)
         return pwr_fault;
 }
 
+static int hpc_get_emi_status(struct slot *slot, u8 *status)
+{
+        struct controller *ctrl = slot->ctrl;
+        u16 slot_status;
+        int retval = 0;
+
+        DBG_ENTER_ROUTINE
+
+        retval = pciehp_readw(ctrl, SLOTSTATUS, &slot_status);
+        if (retval) {
+                err("%s : Cannot check EMI status\n", __FUNCTION__);
+                return retval;
+        }
+        *status = (slot_status & EMI_STATE) >> EMI_STATUS_BIT;
+
+        DBG_LEAVE_ROUTINE
+        return retval;
+}
+
+static int hpc_toggle_emi(struct slot *slot)
+{
+        struct controller *ctrl = slot->ctrl;
+        u16 slot_cmd = 0;
+        u16 slot_ctrl;
+        int rc = 0;
+
+        DBG_ENTER_ROUTINE
+
+        rc = pciehp_readw(ctrl, SLOTCTRL, &slot_ctrl);
+        if (rc) {
+                err("%s : hp_register_read_word SLOT_CTRL failed\n",
+                        __FUNCTION__);
+                return rc;
+        }
+
+        slot_cmd = (slot_ctrl | EMI_CTRL);
+        if (!pciehp_poll_mode)
+                slot_cmd = slot_cmd | HP_INTR_ENABLE;
+
+        pcie_write_cmd(slot, slot_cmd);
+        slot->last_emi_toggle = get_seconds();
+        DBG_LEAVE_ROUTINE
+        return rc;
+}
+
 static int hpc_set_attention_status(struct slot *slot, u8 value)
 {
         struct controller *ctrl = slot->ctrl;
@@ -1009,6 +1062,8 @@ static struct hpc_ops pciehp_hpc_ops = {
         .get_attention_status           = hpc_get_attention_status,
         .get_latch_status               = hpc_get_latch_status,
         .get_adapter_status             = hpc_get_adapter_status,
+        .get_emi_status                 = hpc_get_emi_status,
+        .toggle_emi                     = hpc_toggle_emi,
 
         .get_max_bus_speed              = hpc_get_max_lnk_speed,
         .get_cur_bus_speed              = hpc_get_cur_lnk_speed,