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

Commit 34d03419 authored by Kristen Carlson Accardi's avatar Kristen Carlson Accardi Committed by Greg Kroah-Hartman
Browse files

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

parent 262303fe
Loading
Loading
Loading
Loading
+5 −0
Original line number Diff line number Diff line
@@ -69,6 +69,7 @@ struct slot {
	struct hotplug_slot *hotplug_slot;
	struct list_head	slot_list;
	char name[SLOT_NAME_SIZE];
	unsigned long last_emi_toggle;
};

struct event_info {
@@ -138,6 +139,7 @@ struct controller {
#define ATTN_LED_PRSN	0x00000008
#define PWR_LED_PRSN	0x00000010
#define HP_SUPR_RM_SUP	0x00000020
#define EMI_PRSN	0x00020000

#define ATTN_BUTTN(cap)		(cap & ATTN_BUTTN_PRSN)
#define POWER_CTRL(cap)		(cap & PWR_CTRL_PRSN)
@@ -145,6 +147,7 @@ struct controller {
#define ATTN_LED(cap)		(cap & ATTN_LED_PRSN)
#define PWR_LED(cap)		(cap & PWR_LED_PRSN) 
#define HP_SUPR_RM(cap)		(cap & HP_SUPR_RM_SUP)
#define EMI(cap)		(cap & EMI_PRSN)

extern int pciehp_event_start_thread(void);
extern void pciehp_event_stop_thread(void);
@@ -182,6 +185,8 @@ struct hpc_ops {
	int (*set_attention_status)(struct slot *slot, u8 status);
	int (*get_latch_status)(struct slot *slot, u8 *status);
	int (*get_adapter_status)(struct slot *slot, u8 *status);
	int (*get_emi_status)(struct slot *slot, u8 *status);
	int (*toggle_emi)(struct slot *slot);
	int (*get_max_bus_speed)(struct slot *slot, enum pci_bus_speed *speed);
	int (*get_cur_bus_speed)(struct slot *slot, enum pci_bus_speed *speed);
	int (*get_max_lnk_width)(struct slot *slot, enum pcie_link_width *val);
+103 −0
Original line number Diff line number Diff line
@@ -34,6 +34,7 @@
#include <linux/pci.h>
#include "pciehp.h"
#include <linux/interrupt.h>
#include <linux/time.h>

/* Global variables */
int pciehp_debug;
@@ -87,6 +88,95 @@ static struct hotplug_slot_ops pciehp_hotplug_slot_ops = {
  	.get_cur_bus_speed =	get_cur_bus_speed,
};

/*
 * Check the status of the Electro Mechanical Interlock (EMI)
 */
static int get_lock_status(struct hotplug_slot *hotplug_slot, u8 *value)
{
	struct slot *slot = hotplug_slot->private;
	return (slot->hpc_ops->get_emi_status(slot, value));
}

/*
 * sysfs interface for the Electro Mechanical Interlock (EMI)
 * 1 == locked, 0 == unlocked
 */
static ssize_t lock_read_file(struct hotplug_slot *slot, char *buf)
{
	int retval;
	u8 value;

	retval = get_lock_status(slot, &value);
	if (retval)
		goto lock_read_exit;
	retval = sprintf (buf, "%d\n", value);

lock_read_exit:
	return retval;
}

/*
 * Change the status of the Electro Mechanical Interlock (EMI)
 * This is a toggle - in addition there must be at least 1 second
 * in between toggles.
 */
static int set_lock_status(struct hotplug_slot *hotplug_slot, u8 status)
{
	struct slot *slot = hotplug_slot->private;
	int retval;
	u8 value;

	mutex_lock(&slot->ctrl->crit_sect);

	/* has it been >1 sec since our last toggle? */
	if ((get_seconds() - slot->last_emi_toggle) < 1)
		return -EINVAL;

	/* see what our current state is */
	retval = get_lock_status(hotplug_slot, &value);
	if (retval || (value == status))
		goto set_lock_exit;

	slot->hpc_ops->toggle_emi(slot);
set_lock_exit:
	mutex_unlock(&slot->ctrl->crit_sect);
	return 0;
}

/*
 * sysfs interface which allows the user to toggle the Electro Mechanical
 * Interlock.  Valid values are either 0 or 1.  0 == unlock, 1 == lock
 */
static ssize_t lock_write_file(struct hotplug_slot *slot, const char *buf,
		size_t count)
{
	unsigned long llock;
	u8 lock;
	int retval = 0;

	llock = simple_strtoul(buf, NULL, 10);
	lock = (u8)(llock & 0xff);

	switch (lock) {
		case 0:
		case 1:
			retval = set_lock_status(slot, lock);
			break;
		default:
			err ("%d is an invalid lock value\n", lock);
			retval = -EINVAL;
	}
	if (retval)
		return retval;
	return count;
}

static struct hotplug_slot_attribute hotplug_slot_attr_lock = {
	.attr = {.name = "lock", .mode = S_IFREG | S_IRUGO | S_IWUSR},
	.show = lock_read_file,
	.store = lock_write_file
};

/**
 * release_slot - free up the memory used by a slot
 * @hotplug_slot: slot to free
@@ -159,6 +249,16 @@ static int init_slots(struct controller *ctrl)
			err ("pci_hp_register failed with error %d\n", retval);
			goto error_info;
		}
		/* create additional sysfs entries */
		if (EMI(ctrl->ctrlcap)) {
			retval = sysfs_create_file(&hotplug_slot->kobj,
				&hotplug_slot_attr_lock.attr);
			if (retval) {
				pci_hp_deregister(hotplug_slot);
				err("cannot create additional sysfs entries\n");
				goto error_info;
			}
		}

		list_add(&slot->slot_list, &ctrl->slot_list);
	}
@@ -183,6 +283,9 @@ static void cleanup_slots(struct controller *ctrl)
	list_for_each_safe(tmp, next, &ctrl->slot_list) {
		slot = list_entry(tmp, struct slot, slot_list);
		list_del(&slot->slot_list);
		if (EMI(ctrl->ctrlcap))
			sysfs_remove_file(&slot->hotplug_slot->kobj,
				&hotplug_slot_attr_lock.attr);
		pci_hp_deregister(slot->hotplug_slot);
	}
}
+55 −0
Original line number Diff line number Diff line
@@ -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,