Adding upstream version 6.1.76.upstream/6.1.76upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 2307 insertions, 0 deletions

diff --git a/drivers/char/ipmi/ipmi_si_intf.c b/drivers/char/ipmi/ipmi_si_intf.c
new file mode 100644
index 000000000..5cd031f3f
--- /dev/null
+++ b/drivers/char/ipmi/ipmi_si_intf.c
@@ -0,0 +1,2307 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * ipmi_si.c
+ *
+ * The interface to the IPMI driver for the system interfaces (KCS, SMIC,
+ * BT).
+ *
+ * Author: MontaVista Software, Inc.
+ *         Corey Minyard <minyard@mvista.com>
+ *         source@mvista.com
+ *
+ * Copyright 2002 MontaVista Software Inc.
+ * Copyright 2006 IBM Corp., Christian Krafft <krafft@de.ibm.com>
+ */
+
+/*
+ * This file holds the "policy" for the interface to the SMI state
+ * machine.  It does the configuration, handles timers and interrupts,
+ * and drives the real SMI state machine.
+ */
+
+#define pr_fmt(fmt) "ipmi_si: " fmt
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/sched.h>
+#include <linux/seq_file.h>
+#include <linux/timer.h>
+#include <linux/errno.h>
+#include <linux/spinlock.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/list.h>
+#include <linux/notifier.h>
+#include <linux/mutex.h>
+#include <linux/kthread.h>
+#include <asm/irq.h>
+#include <linux/interrupt.h>
+#include <linux/rcupdate.h>
+#include <linux/ipmi.h>
+#include <linux/ipmi_smi.h>
+#include "ipmi_si.h"
+#include "ipmi_si_sm.h"
+#include <linux/string.h>
+#include <linux/ctype.h>
+
+/* Measure times between events in the driver. */
+#undef DEBUG_TIMING
+
+/* Call every 10 ms. */
+#define SI_TIMEOUT_TIME_USEC	10000
+#define SI_USEC_PER_JIFFY	(1000000/HZ)
+#define SI_TIMEOUT_JIFFIES	(SI_TIMEOUT_TIME_USEC/SI_USEC_PER_JIFFY)
+#define SI_SHORT_TIMEOUT_USEC  250 /* .25ms when the SM request a
+				      short timeout */
+
+enum si_intf_state {
+	SI_NORMAL,
+	SI_GETTING_FLAGS,
+	SI_GETTING_EVENTS,
+	SI_CLEARING_FLAGS,
+	SI_GETTING_MESSAGES,
+	SI_CHECKING_ENABLES,
+	SI_SETTING_ENABLES
+	/* FIXME - add watchdog stuff. */
+};
+
+/* Some BT-specific defines we need here. */
+#define IPMI_BT_INTMASK_REG		2
+#define IPMI_BT_INTMASK_CLEAR_IRQ_BIT	2
+#define IPMI_BT_INTMASK_ENABLE_IRQ_BIT	1
+
+/* 'invalid' to allow a firmware-specified interface to be disabled */
+const char *const si_to_str[] = { "invalid", "kcs", "smic", "bt", NULL };
+
+static bool initialized;
+
+/*
+ * Indexes into stats[] in smi_info below.
+ */
+enum si_stat_indexes {
+	/*
+	 * Number of times the driver requested a timer while an operation
+	 * was in progress.
+	 */
+	SI_STAT_short_timeouts = 0,
+
+	/*
+	 * Number of times the driver requested a timer while nothing was in
+	 * progress.
+	 */
+	SI_STAT_long_timeouts,
+
+	/* Number of times the interface was idle while being polled. */
+	SI_STAT_idles,
+
+	/* Number of interrupts the driver handled. */
+	SI_STAT_interrupts,
+
+	/* Number of time the driver got an ATTN from the hardware. */
+	SI_STAT_attentions,
+
+	/* Number of times the driver requested flags from the hardware. */
+	SI_STAT_flag_fetches,
+
+	/* Number of times the hardware didn't follow the state machine. */
+	SI_STAT_hosed_count,
+
+	/* Number of completed messages. */
+	SI_STAT_complete_transactions,
+
+	/* Number of IPMI events received from the hardware. */
+	SI_STAT_events,
+
+	/* Number of watchdog pretimeouts. */
+	SI_STAT_watchdog_pretimeouts,
+
+	/* Number of asynchronous messages received. */
+	SI_STAT_incoming_messages,
+
+
+	/* This *must* remain last, add new values above this. */
+	SI_NUM_STATS
+};
+
+struct smi_info {
+	int                    si_num;
+	struct ipmi_smi        *intf;
+	struct si_sm_data      *si_sm;
+	const struct si_sm_handlers *handlers;
+	spinlock_t             si_lock;
+	struct ipmi_smi_msg    *waiting_msg;
+	struct ipmi_smi_msg    *curr_msg;
+	enum si_intf_state     si_state;
+
+	/*
+	 * Used to handle the various types of I/O that can occur with
+	 * IPMI
+	 */
+	struct si_sm_io io;
+
+	/*
+	 * Per-OEM handler, called from handle_flags().  Returns 1
+	 * when handle_flags() needs to be re-run or 0 indicating it
+	 * set si_state itself.
+	 */
+	int (*oem_data_avail_handler)(struct smi_info *smi_info);
+
+	/*
+	 * Flags from the last GET_MSG_FLAGS command, used when an ATTN
+	 * is set to hold the flags until we are done handling everything
+	 * from the flags.
+	 */
+#define RECEIVE_MSG_AVAIL	0x01
+#define EVENT_MSG_BUFFER_FULL	0x02
+#define WDT_PRE_TIMEOUT_INT	0x08
+#define OEM0_DATA_AVAIL     0x20
+#define OEM1_DATA_AVAIL     0x40
+#define OEM2_DATA_AVAIL     0x80
+#define OEM_DATA_AVAIL      (OEM0_DATA_AVAIL | \
+			     OEM1_DATA_AVAIL | \
+			     OEM2_DATA_AVAIL)
+	unsigned char       msg_flags;
+
+	/* Does the BMC have an event buffer? */
+	bool		    has_event_buffer;
+
+	/*
+	 * If set to true, this will request events the next time the
+	 * state machine is idle.
+	 */
+	atomic_t            req_events;
+
+	/*
+	 * If true, run the state machine to completion on every send
+	 * call.  Generally used after a panic to make sure stuff goes
+	 * out.
+	 */
+	bool                run_to_completion;
+
+	/* The timer for this si. */
+	struct timer_list   si_timer;
+
+	/* This flag is set, if the timer can be set */
+	bool		    timer_can_start;
+
+	/* This flag is set, if the timer is running (timer_pending() isn't enough) */
+	bool		    timer_running;
+
+	/* The time (in jiffies) the last timeout occurred at. */
+	unsigned long       last_timeout_jiffies;
+
+	/* Are we waiting for the events, pretimeouts, received msgs? */
+	atomic_t            need_watch;
+
+	/*
+	 * The driver will disable interrupts when it gets into a
+	 * situation where it cannot handle messages due to lack of
+	 * memory.  Once that situation clears up, it will re-enable
+	 * interrupts.
+	 */
+	bool interrupt_disabled;
+
+	/*
+	 * Does the BMC support events?
+	 */
+	bool supports_event_msg_buff;
+
+	/*
+	 * Can we disable interrupts the global enables receive irq
+	 * bit?  There are currently two forms of brokenness, some
+	 * systems cannot disable the bit (which is technically within
+	 * the spec but a bad idea) and some systems have the bit
+	 * forced to zero even though interrupts work (which is
+	 * clearly outside the spec).  The next bool tells which form
+	 * of brokenness is present.
+	 */
+	bool cannot_disable_irq;
+
+	/*
+	 * Some systems are broken and cannot set the irq enable
+	 * bit, even if they support interrupts.
+	 */
+	bool irq_enable_broken;
+
+	/* Is the driver in maintenance mode? */
+	bool in_maintenance_mode;
+
+	/*
+	 * Did we get an attention that we did not handle?
+	 */
+	bool got_attn;
+
+	/* From the get device id response... */
+	struct ipmi_device_id device_id;
+
+	/* Have we added the device group to the device? */
+	bool dev_group_added;
+
+	/* Counters and things for the proc filesystem. */
+	atomic_t stats[SI_NUM_STATS];
+
+	struct task_struct *thread;
+
+	struct list_head link;
+};
+
+#define smi_inc_stat(smi, stat) \
+	atomic_inc(&(smi)->stats[SI_STAT_ ## stat])
+#define smi_get_stat(smi, stat) \
+	((unsigned int) atomic_read(&(smi)->stats[SI_STAT_ ## stat]))
+
+#define IPMI_MAX_INTFS 4
+static int force_kipmid[IPMI_MAX_INTFS];
+static int num_force_kipmid;
+
+static unsigned int kipmid_max_busy_us[IPMI_MAX_INTFS];
+static int num_max_busy_us;
+
+static bool unload_when_empty = true;
+
+static int try_smi_init(struct smi_info *smi);
+static void cleanup_one_si(struct smi_info *smi_info);
+static void cleanup_ipmi_si(void);
+
+#ifdef DEBUG_TIMING
+void debug_timestamp(struct smi_info *smi_info, char *msg)
+{
+	struct timespec64 t;
+
+	ktime_get_ts64(&t);
+	dev_dbg(smi_info->io.dev, "**%s: %lld.%9.9ld\n",
+		msg, t.tv_sec, t.tv_nsec);
+}
+#else
+#define debug_timestamp(smi_info, x)
+#endif
+
+static ATOMIC_NOTIFIER_HEAD(xaction_notifier_list);
+static int register_xaction_notifier(struct notifier_block *nb)
+{
+	return atomic_notifier_chain_register(&xaction_notifier_list, nb);
+}
+
+static void deliver_recv_msg(struct smi_info *smi_info,
+			     struct ipmi_smi_msg *msg)
+{
+	/* Deliver the message to the upper layer. */
+	ipmi_smi_msg_received(smi_info->intf, msg);
+}
+
+static void return_hosed_msg(struct smi_info *smi_info, int cCode)
+{
+	struct ipmi_smi_msg *msg = smi_info->curr_msg;
+
+	if (cCode < 0 || cCode > IPMI_ERR_UNSPECIFIED)
+		cCode = IPMI_ERR_UNSPECIFIED;
+	/* else use it as is */
+
+	/* Make it a response */
+	msg->rsp[0] = msg->data[0] | 4;
+	msg->rsp[1] = msg->data[1];
+	msg->rsp[2] = cCode;
+	msg->rsp_size = 3;
+
+	smi_info->curr_msg = NULL;
+	deliver_recv_msg(smi_info, msg);
+}
+
+static enum si_sm_result start_next_msg(struct smi_info *smi_info)
+{
+	int              rv;
+
+	if (!smi_info->waiting_msg) {
+		smi_info->curr_msg = NULL;
+		rv = SI_SM_IDLE;
+	} else {
+		int err;
+
+		smi_info->curr_msg = smi_info->waiting_msg;
+		smi_info->waiting_msg = NULL;
+		debug_timestamp(smi_info, "Start2");
+		err = atomic_notifier_call_chain(&xaction_notifier_list,
+				0, smi_info);
+		if (err & NOTIFY_STOP_MASK) {
+			rv = SI_SM_CALL_WITHOUT_DELAY;
+			goto out;
+		}
+		err = smi_info->handlers->start_transaction(
+			smi_info->si_sm,
+			smi_info->curr_msg->data,
+			smi_info->curr_msg->data_size);
+		if (err)
+			return_hosed_msg(smi_info, err);
+
+		rv = SI_SM_CALL_WITHOUT_DELAY;
+	}
+out:
+	return rv;
+}
+
+static void smi_mod_timer(struct smi_info *smi_info, unsigned long new_val)
+{
+	if (!smi_info->timer_can_start)
+		return;
+	smi_info->last_timeout_jiffies = jiffies;
+	mod_timer(&smi_info->si_timer, new_val);
+	smi_info->timer_running = true;
+}
+
+/*
+ * Start a new message and (re)start the timer and thread.
+ */
+static void start_new_msg(struct smi_info *smi_info, unsigned char *msg,
+			  unsigned int size)
+{
+	smi_mod_timer(smi_info, jiffies + SI_TIMEOUT_JIFFIES);
+
+	if (smi_info->thread)
+		wake_up_process(smi_info->thread);
+
+	smi_info->handlers->start_transaction(smi_info->si_sm, msg, size);
+}
+
+static void start_check_enables(struct smi_info *smi_info)
+{
+	unsigned char msg[2];
+
+	msg[0] = (IPMI_NETFN_APP_REQUEST << 2);
+	msg[1] = IPMI_GET_BMC_GLOBAL_ENABLES_CMD;
+
+	start_new_msg(smi_info, msg, 2);
+	smi_info->si_state = SI_CHECKING_ENABLES;
+}
+
+static void start_clear_flags(struct smi_info *smi_info)
+{
+	unsigned char msg[3];
+
+	/* Make sure the watchdog pre-timeout flag is not set at startup. */
+	msg[0] = (IPMI_NETFN_APP_REQUEST << 2);
+	msg[1] = IPMI_CLEAR_MSG_FLAGS_CMD;
+	msg[2] = WDT_PRE_TIMEOUT_INT;
+
+	start_new_msg(smi_info, msg, 3);
+	smi_info->si_state = SI_CLEARING_FLAGS;
+}
+
+static void start_getting_msg_queue(struct smi_info *smi_info)
+{
+	smi_info->curr_msg->data[0] = (IPMI_NETFN_APP_REQUEST << 2);
+	smi_info->curr_msg->data[1] = IPMI_GET_MSG_CMD;
+	smi_info->curr_msg->data_size = 2;
+
+	start_new_msg(smi_info, smi_info->curr_msg->data,
+		      smi_info->curr_msg->data_size);
+	smi_info->si_state = SI_GETTING_MESSAGES;
+}
+
+static void start_getting_events(struct smi_info *smi_info)
+{
+	smi_info->curr_msg->data[0] = (IPMI_NETFN_APP_REQUEST << 2);
+	smi_info->curr_msg->data[1] = IPMI_READ_EVENT_MSG_BUFFER_CMD;
+	smi_info->curr_msg->data_size = 2;
+
+	start_new_msg(smi_info, smi_info->curr_msg->data,
+		      smi_info->curr_msg->data_size);
+	smi_info->si_state = SI_GETTING_EVENTS;
+}
+
+/*
+ * When we have a situtaion where we run out of memory and cannot
+ * allocate messages, we just leave them in the BMC and run the system
+ * polled until we can allocate some memory.  Once we have some
+ * memory, we will re-enable the interrupt.
+ *
+ * Note that we cannot just use disable_irq(), since the interrupt may
+ * be shared.
+ */
+static inline bool disable_si_irq(struct smi_info *smi_info)
+{
+	if ((smi_info->io.irq) && (!smi_info->interrupt_disabled)) {
+		smi_info->interrupt_disabled = true;
+		start_check_enables(smi_info);
+		return true;
+	}
+	return false;
+}
+
+static inline bool enable_si_irq(struct smi_info *smi_info)
+{
+	if ((smi_info->io.irq) && (smi_info->interrupt_disabled)) {
+		smi_info->interrupt_disabled = false;
+		start_check_enables(smi_info);
+		return true;
+	}
+	return false;
+}
+
+/*
+ * Allocate a message.  If unable to allocate, start the interrupt
+ * disable process and return NULL.  If able to allocate but
+ * interrupts are disabled, free the message and return NULL after
+ * starting the interrupt enable process.
+ */
+static struct ipmi_smi_msg *alloc_msg_handle_irq(struct smi_info *smi_info)
+{
+	struct ipmi_smi_msg *msg;
+
+	msg = ipmi_alloc_smi_msg();
+	if (!msg) {
+		if (!disable_si_irq(smi_info))
+			smi_info->si_state = SI_NORMAL;
+	} else if (enable_si_irq(smi_info)) {
+		ipmi_free_smi_msg(msg);
+		msg = NULL;
+	}
+	return msg;
+}
+
+static void handle_flags(struct smi_info *smi_info)
+{
+retry:
+	if (smi_info->msg_flags & WDT_PRE_TIMEOUT_INT) {
+		/* Watchdog pre-timeout */
+		smi_inc_stat(smi_info, watchdog_pretimeouts);
+
+		start_clear_flags(smi_info);
+		smi_info->msg_flags &= ~WDT_PRE_TIMEOUT_INT;
+		ipmi_smi_watchdog_pretimeout(smi_info->intf);
+	} else if (smi_info->msg_flags & RECEIVE_MSG_AVAIL) {
+		/* Messages available. */
+		smi_info->curr_msg = alloc_msg_handle_irq(smi_info);
+		if (!smi_info->curr_msg)
+			return;
+
+		start_getting_msg_queue(smi_info);
+	} else if (smi_info->msg_flags & EVENT_MSG_BUFFER_FULL) {
+		/* Events available. */
+		smi_info->curr_msg = alloc_msg_handle_irq(smi_info);
+		if (!smi_info->curr_msg)
+			return;
+
+		start_getting_events(smi_info);
+	} else if (smi_info->msg_flags & OEM_DATA_AVAIL &&
+		   smi_info->oem_data_avail_handler) {
+		if (smi_info->oem_data_avail_handler(smi_info))
+			goto retry;
+	} else
+		smi_info->si_state = SI_NORMAL;
+}
+
+/*
+ * Global enables we care about.
+ */
+#define GLOBAL_ENABLES_MASK (IPMI_BMC_EVT_MSG_BUFF | IPMI_BMC_RCV_MSG_INTR | \
+			     IPMI_BMC_EVT_MSG_INTR)
+
+static u8 current_global_enables(struct smi_info *smi_info, u8 base,
+				 bool *irq_on)
+{
+	u8 enables = 0;
+
+	if (smi_info->supports_event_msg_buff)
+		enables |= IPMI_BMC_EVT_MSG_BUFF;
+
+	if (((smi_info->io.irq && !smi_info->interrupt_disabled) ||
+	     smi_info->cannot_disable_irq) &&
+	    !smi_info->irq_enable_broken)
+		enables |= IPMI_BMC_RCV_MSG_INTR;
+
+	if (smi_info->supports_event_msg_buff &&
+	    smi_info->io.irq && !smi_info->interrupt_disabled &&
+	    !smi_info->irq_enable_broken)
+		enables |= IPMI_BMC_EVT_MSG_INTR;
+
+	*irq_on = enables & (IPMI_BMC_EVT_MSG_INTR | IPMI_BMC_RCV_MSG_INTR);
+
+	return enables;
+}
+
+static void check_bt_irq(struct smi_info *smi_info, bool irq_on)
+{
+	u8 irqstate = smi_info->io.inputb(&smi_info->io, IPMI_BT_INTMASK_REG);
+
+	irqstate &= IPMI_BT_INTMASK_ENABLE_IRQ_BIT;
+
+	if ((bool)irqstate == irq_on)
+		return;
+
+	if (irq_on)
+		smi_info->io.outputb(&smi_info->io, IPMI_BT_INTMASK_REG,
+				     IPMI_BT_INTMASK_ENABLE_IRQ_BIT);
+	else
+		smi_info->io.outputb(&smi_info->io, IPMI_BT_INTMASK_REG, 0);
+}
+
+static void handle_transaction_done(struct smi_info *smi_info)
+{
+	struct ipmi_smi_msg *msg;
+
+	debug_timestamp(smi_info, "Done");
+	switch (smi_info->si_state) {
+	case SI_NORMAL:
+		if (!smi_info->curr_msg)
+			break;
+
+		smi_info->curr_msg->rsp_size
+			= smi_info->handlers->get_result(
+				smi_info->si_sm,
+				smi_info->curr_msg->rsp,
+				IPMI_MAX_MSG_LENGTH);
+
+		/*
+		 * Do this here becase deliver_recv_msg() releases the
+		 * lock, and a new message can be put in during the
+		 * time the lock is released.
+		 */
+		msg = smi_info->curr_msg;
+		smi_info->curr_msg = NULL;
+		deliver_recv_msg(smi_info, msg);
+		break;
+
+	case SI_GETTING_FLAGS:
+	{
+		unsigned char msg[4];
+		unsigned int  len;
+
+		/* We got the flags from the SMI, now handle them. */
+		len = smi_info->handlers->get_result(smi_info->si_sm, msg, 4);
+		if (msg[2] != 0) {
+			/* Error fetching flags, just give up for now. */
+			smi_info->si_state = SI_NORMAL;
+		} else if (len < 4) {
+			/*
+			 * Hmm, no flags.  That's technically illegal, but
+			 * don't use uninitialized data.
+			 */
+			smi_info->si_state = SI_NORMAL;
+		} else {
+			smi_info->msg_flags = msg[3];
+			handle_flags(smi_info);
+		}
+		break;
+	}
+
+	case SI_CLEARING_FLAGS:
+	{
+		unsigned char msg[3];
+
+		/* We cleared the flags. */
+		smi_info->handlers->get_result(smi_info->si_sm, msg, 3);
+		if (msg[2] != 0) {
+			/* Error clearing flags */
+			dev_warn_ratelimited(smi_info->io.dev,
+				 "Error clearing flags: %2.2x\n", msg[2]);
+		}
+		smi_info->si_state = SI_NORMAL;
+		break;
+	}
+
+	case SI_GETTING_EVENTS:
+	{
+		smi_info->curr_msg->rsp_size
+			= smi_info->handlers->get_result(
+				smi_info->si_sm,
+				smi_info->curr_msg->rsp,
+				IPMI_MAX_MSG_LENGTH);
+
+		/*
+		 * Do this here becase deliver_recv_msg() releases the
+		 * lock, and a new message can be put in during the
+		 * time the lock is released.
+		 */
+		msg = smi_info->curr_msg;
+		smi_info->curr_msg = NULL;
+		if (msg->rsp[2] != 0) {
+			/* Error getting event, probably done. */
+			msg->done(msg);
+
+			/* Take off the event flag. */
+			smi_info->msg_flags &= ~EVENT_MSG_BUFFER_FULL;
+			handle_flags(smi_info);
+		} else {
+			smi_inc_stat(smi_info, events);
+
+			/*
+			 * Do this before we deliver the message
+			 * because delivering the message releases the
+			 * lock and something else can mess with the
+			 * state.
+			 */
+			handle_flags(smi_info);
+
+			deliver_recv_msg(smi_info, msg);
+		}
+		break;
+	}
+
+	case SI_GETTING_MESSAGES:
+	{
+		smi_info->curr_msg->rsp_size
+			= smi_info->handlers->get_result(
+				smi_info->si_sm,
+				smi_info->curr_msg->rsp,
+				IPMI_MAX_MSG_LENGTH);
+
+		/*
+		 * Do this here becase deliver_recv_msg() releases the
+		 * lock, and a new message can be put in during the
+		 * time the lock is released.
+		 */
+		msg = smi_info->curr_msg;
+		smi_info->curr_msg = NULL;
+		if (msg->rsp[2] != 0) {
+			/* Error getting event, probably done. */
+			msg->done(msg);
+
+			/* Take off the msg flag. */
+			smi_info->msg_flags &= ~RECEIVE_MSG_AVAIL;
+			handle_flags(smi_info);
+		} else {
+			smi_inc_stat(smi_info, incoming_messages);
+
+			/*
+			 * Do this before we deliver the message
+			 * because delivering the message releases the
+			 * lock and something else can mess with the
+			 * state.
+			 */
+			handle_flags(smi_info);
+
+			deliver_recv_msg(smi_info, msg);
+		}
+		break;
+	}
+
+	case SI_CHECKING_ENABLES:
+	{
+		unsigned char msg[4];
+		u8 enables;
+		bool irq_on;
+
+		/* We got the flags from the SMI, now handle them. */
+		smi_info->handlers->get_result(smi_info->si_sm, msg, 4);
+		if (msg[2] != 0) {
+			dev_warn_ratelimited(smi_info->io.dev,
+				"Couldn't get irq info: %x,\n"
+				"Maybe ok, but ipmi might run very slowly.\n",
+				msg[2]);
+			smi_info->si_state = SI_NORMAL;
+			break;
+		}
+		enables = current_global_enables(smi_info, 0, &irq_on);
+		if (smi_info->io.si_type == SI_BT)
+			/* BT has its own interrupt enable bit. */
+			check_bt_irq(smi_info, irq_on);
+		if (enables != (msg[3] & GLOBAL_ENABLES_MASK)) {
+			/* Enables are not correct, fix them. */
+			msg[0] = (IPMI_NETFN_APP_REQUEST << 2);
+			msg[1] = IPMI_SET_BMC_GLOBAL_ENABLES_CMD;
+			msg[2] = enables | (msg[3] & ~GLOBAL_ENABLES_MASK);
+			smi_info->handlers->start_transaction(
+				smi_info->si_sm, msg, 3);
+			smi_info->si_state = SI_SETTING_ENABLES;
+		} else if (smi_info->supports_event_msg_buff) {
+			smi_info->curr_msg = ipmi_alloc_smi_msg();
+			if (!smi_info->curr_msg) {
+				smi_info->si_state = SI_NORMAL;
+				break;
+			}
+			start_getting_events(smi_info);
+		} else {
+			smi_info->si_state = SI_NORMAL;
+		}
+		break;
+	}
+
+	case SI_SETTING_ENABLES:
+	{
+		unsigned char msg[4];
+
+		smi_info->handlers->get_result(smi_info->si_sm, msg, 4);
+		if (msg[2] != 0)
+			dev_warn_ratelimited(smi_info->io.dev,
+				 "Could not set the global enables: 0x%x.\n",
+				 msg[2]);
+
+		if (smi_info->supports_event_msg_buff) {
+			smi_info->curr_msg = ipmi_alloc_smi_msg();
+			if (!smi_info->curr_msg) {
+				smi_info->si_state = SI_NORMAL;
+				break;
+			}
+			start_getting_events(smi_info);
+		} else {
+			smi_info->si_state = SI_NORMAL;
+		}
+		break;
+	}
+	}
+}
+
+/*
+ * Called on timeouts and events.  Timeouts should pass the elapsed
+ * time, interrupts should pass in zero.  Must be called with
+ * si_lock held and interrupts disabled.
+ */
+static enum si_sm_result smi_event_handler(struct smi_info *smi_info,
+					   int time)
+{
+	enum si_sm_result si_sm_result;
+
+restart:
+	/*
+	 * There used to be a loop here that waited a little while
+	 * (around 25us) before giving up.  That turned out to be
+	 * pointless, the minimum delays I was seeing were in the 300us
+	 * range, which is far too long to wait in an interrupt.  So
+	 * we just run until the state machine tells us something
+	 * happened or it needs a delay.
+	 */
+	si_sm_result = smi_info->handlers->event(smi_info->si_sm, time);
+	time = 0;
+	while (si_sm_result == SI_SM_CALL_WITHOUT_DELAY)
+		si_sm_result = smi_info->handlers->event(smi_info->si_sm, 0);
+
+	if (si_sm_result == SI_SM_TRANSACTION_COMPLETE) {
+		smi_inc_stat(smi_info, complete_transactions);
+
+		handle_transaction_done(smi_info);
+		goto restart;
+	} else if (si_sm_result == SI_SM_HOSED) {
+		smi_inc_stat(smi_info, hosed_count);
+
+		/*
+		 * Do the before return_hosed_msg, because that
+		 * releases the lock.
+		 */
+		smi_info->si_state = SI_NORMAL;
+		if (smi_info->curr_msg != NULL) {
+			/*
+			 * If we were handling a user message, format
+			 * a response to send to the upper layer to
+			 * tell it about the error.
+			 */
+			return_hosed_msg(smi_info, IPMI_ERR_UNSPECIFIED);
+		}
+		goto restart;
+	}
+
+	/*
+	 * We prefer handling attn over new messages.  But don't do
+	 * this if there is not yet an upper layer to handle anything.
+	 */
+	if (si_sm_result == SI_SM_ATTN || smi_info->got_attn) {
+		unsigned char msg[2];
+
+		if (smi_info->si_state != SI_NORMAL) {
+			/*
+			 * We got an ATTN, but we are doing something else.
+			 * Handle the ATTN later.
+			 */
+			smi_info->got_attn = true;
+		} else {
+			smi_info->got_attn = false;
+			smi_inc_stat(smi_info, attentions);
+
+			/*
+			 * Got a attn, send down a get message flags to see
+			 * what's causing it.  It would be better to handle
+			 * this in the upper layer, but due to the way
+			 * interrupts work with the SMI, that's not really
+			 * possible.
+			 */
+			msg[0] = (IPMI_NETFN_APP_REQUEST << 2);
+			msg[1] = IPMI_GET_MSG_FLAGS_CMD;
+
+			start_new_msg(smi_info, msg, 2);
+			smi_info->si_state = SI_GETTING_FLAGS;
+			goto restart;
+		}
+	}
+
+	/* If we are currently idle, try to start the next message. */
+	if (si_sm_result == SI_SM_IDLE) {
+		smi_inc_stat(smi_info, idles);
+
+		si_sm_result = start_next_msg(smi_info);
+		if (si_sm_result != SI_SM_IDLE)
+			goto restart;
+	}
+
+	if ((si_sm_result == SI_SM_IDLE)
+	    && (atomic_read(&smi_info->req_events))) {
+		/*
+		 * We are idle and the upper layer requested that I fetch
+		 * events, so do so.
+		 */
+		atomic_set(&smi_info->req_events, 0);
+
+		/*
+		 * Take this opportunity to check the interrupt and
+		 * message enable state for the BMC.  The BMC can be
+		 * asynchronously reset, and may thus get interrupts
+		 * disable and messages disabled.
+		 */
+		if (smi_info->supports_event_msg_buff || smi_info->io.irq) {
+			start_check_enables(smi_info);
+		} else {
+			smi_info->curr_msg = alloc_msg_handle_irq(smi_info);
+			if (!smi_info->curr_msg)
+				goto out;
+
+			start_getting_events(smi_info);
+		}
+		goto restart;
+	}
+
+	if (si_sm_result == SI_SM_IDLE && smi_info->timer_running) {
+		/* Ok it if fails, the timer will just go off. */
+		if (del_timer(&smi_info->si_timer))
+			smi_info->timer_running = false;
+	}
+
+out:
+	return si_sm_result;
+}
+
+static void check_start_timer_thread(struct smi_info *smi_info)
+{
+	if (smi_info->si_state == SI_NORMAL && smi_info->curr_msg == NULL) {
+		smi_mod_timer(smi_info, jiffies + SI_TIMEOUT_JIFFIES);
+
+		if (smi_info->thread)
+			wake_up_process(smi_info->thread);
+
+		start_next_msg(smi_info);
+		smi_event_handler(smi_info, 0);
+	}
+}
+
+static void flush_messages(void *send_info)
+{
+	struct smi_info *smi_info = send_info;
+	enum si_sm_result result;
+
+	/*
+	 * Currently, this function is called only in run-to-completion
+	 * mode.  This means we are single-threaded, no need for locks.
+	 */
+	result = smi_event_handler(smi_info, 0);
+	while (result != SI_SM_IDLE) {
+		udelay(SI_SHORT_TIMEOUT_USEC);
+		result = smi_event_handler(smi_info, SI_SHORT_TIMEOUT_USEC);
+	}
+}
+
+static void sender(void                *send_info,
+		   struct ipmi_smi_msg *msg)
+{
+	struct smi_info   *smi_info = send_info;
+	unsigned long     flags;
+
+	debug_timestamp(smi_info, "Enqueue");
+
+	if (smi_info->run_to_completion) {
+		/*
+		 * If we are running to completion, start it.  Upper
+		 * layer will call flush_messages to clear it out.
+		 */
+		smi_info->waiting_msg = msg;
+		return;
+	}
+
+	spin_lock_irqsave(&smi_info->si_lock, flags);
+	/*
+	 * The following two lines don't need to be under the lock for
+	 * the lock's sake, but they do need SMP memory barriers to
+	 * avoid getting things out of order.  We are already claiming
+	 * the lock, anyway, so just do it under the lock to avoid the
+	 * ordering problem.
+	 */
+	BUG_ON(smi_info->waiting_msg);
+	smi_info->waiting_msg = msg;
+	check_start_timer_thread(smi_info);
+	spin_unlock_irqrestore(&smi_info->si_lock, flags);
+}
+
+static void set_run_to_completion(void *send_info, bool i_run_to_completion)
+{
+	struct smi_info   *smi_info = send_info;
+
+	smi_info->run_to_completion = i_run_to_completion;
+	if (i_run_to_completion)
+		flush_messages(smi_info);
+}
+
+/*
+ * Use -1 as a special constant to tell that we are spinning in kipmid
+ * looking for something and not delaying between checks
+ */
+#define IPMI_TIME_NOT_BUSY ns_to_ktime(-1ull)
+static inline bool ipmi_thread_busy_wait(enum si_sm_result smi_result,
+					 const struct smi_info *smi_info,
+					 ktime_t *busy_until)
+{
+	unsigned int max_busy_us = 0;
+
+	if (smi_info->si_num < num_max_busy_us)
+		max_busy_us = kipmid_max_busy_us[smi_info->si_num];
+	if (max_busy_us == 0 || smi_result != SI_SM_CALL_WITH_DELAY)
+		*busy_until = IPMI_TIME_NOT_BUSY;
+	else if (*busy_until == IPMI_TIME_NOT_BUSY) {
+		*busy_until = ktime_get() + max_busy_us * NSEC_PER_USEC;
+	} else {
+		if (unlikely(ktime_get() > *busy_until)) {
+			*busy_until = IPMI_TIME_NOT_BUSY;
+			return false;
+		}
+	}
+	return true;
+}
+
+
+/*
+ * A busy-waiting loop for speeding up IPMI operation.
+ *
+ * Lousy hardware makes this hard.  This is only enabled for systems
+ * that are not BT and do not have interrupts.  It starts spinning
+ * when an operation is complete or until max_busy tells it to stop
+ * (if that is enabled).  See the paragraph on kimid_max_busy_us in
+ * Documentation/driver-api/ipmi.rst for details.
+ */
+static int ipmi_thread(void *data)
+{
+	struct smi_info *smi_info = data;
+	unsigned long flags;
+	enum si_sm_result smi_result;
+	ktime_t busy_until = IPMI_TIME_NOT_BUSY;
+
+	set_user_nice(current, MAX_NICE);
+	while (!kthread_should_stop()) {
+		int busy_wait;
+
+		spin_lock_irqsave(&(smi_info->si_lock), flags);
+		smi_result = smi_event_handler(smi_info, 0);
+
+		/*
+		 * If the driver is doing something, there is a possible
+		 * race with the timer.  If the timer handler see idle,
+		 * and the thread here sees something else, the timer
+		 * handler won't restart the timer even though it is
+		 * required.  So start it here if necessary.
+		 */
+		if (smi_result != SI_SM_IDLE && !smi_info->timer_running)
+			smi_mod_timer(smi_info, jiffies + SI_TIMEOUT_JIFFIES);
+
+		spin_unlock_irqrestore(&(smi_info->si_lock), flags);
+		busy_wait = ipmi_thread_busy_wait(smi_result, smi_info,
+						  &busy_until);
+		if (smi_result == SI_SM_CALL_WITHOUT_DELAY) {
+			; /* do nothing */
+		} else if (smi_result == SI_SM_CALL_WITH_DELAY && busy_wait) {
+			/*
+			 * In maintenance mode we run as fast as
+			 * possible to allow firmware updates to
+			 * complete as fast as possible, but normally
+			 * don't bang on the scheduler.
+			 */
+			if (smi_info->in_maintenance_mode)
+				schedule();
+			else
+				usleep_range(100, 200);
+		} else if (smi_result == SI_SM_IDLE) {
+			if (atomic_read(&smi_info->need_watch)) {
+				schedule_timeout_interruptible(100);
+			} else {
+				/* Wait to be woken up when we are needed. */
+				__set_current_state(TASK_INTERRUPTIBLE);
+				schedule();
+			}
+		} else {
+			schedule_timeout_interruptible(1);
+		}
+	}
+	return 0;
+}
+
+
+static void poll(void *send_info)
+{
+	struct smi_info *smi_info = send_info;
+	unsigned long flags = 0;
+	bool run_to_completion = smi_info->run_to_completion;
+
+	/*
+	 * Make sure there is some delay in the poll loop so we can
+	 * drive time forward and timeout things.
+	 */
+	udelay(10);
+	if (!run_to_completion)
+		spin_lock_irqsave(&smi_info->si_lock, flags);
+	smi_event_handler(smi_info, 10);
+	if (!run_to_completion)
+		spin_unlock_irqrestore(&smi_info->si_lock, flags);
+}
+
+static void request_events(void *send_info)
+{
+	struct smi_info *smi_info = send_info;
+
+	if (!smi_info->has_event_buffer)
+		return;
+
+	atomic_set(&smi_info->req_events, 1);
+}
+
+static void set_need_watch(void *send_info, unsigned int watch_mask)
+{
+	struct smi_info *smi_info = send_info;
+	unsigned long flags;
+	int enable;
+
+	enable = !!watch_mask;
+
+	atomic_set(&smi_info->need_watch, enable);
+	spin_lock_irqsave(&smi_info->si_lock, flags);
+	check_start_timer_thread(smi_info);
+	spin_unlock_irqrestore(&smi_info->si_lock, flags);
+}
+
+static void smi_timeout(struct timer_list *t)
+{
+	struct smi_info   *smi_info = from_timer(smi_info, t, si_timer);
+	enum si_sm_result smi_result;
+	unsigned long     flags;
+	unsigned long     jiffies_now;
+	long              time_diff;
+	long		  timeout;
+
+	spin_lock_irqsave(&(smi_info->si_lock), flags);
+	debug_timestamp(smi_info, "Timer");
+
+	jiffies_now = jiffies;
+	time_diff = (((long)jiffies_now - (long)smi_info->last_timeout_jiffies)
+		     * SI_USEC_PER_JIFFY);
+	smi_result = smi_event_handler(smi_info, time_diff);
+
+	if ((smi_info->io.irq) && (!smi_info->interrupt_disabled)) {
+		/* Running with interrupts, only do long timeouts. */
+		timeout = jiffies + SI_TIMEOUT_JIFFIES;
+		smi_inc_stat(smi_info, long_timeouts);
+		goto do_mod_timer;
+	}
+
+	/*
+	 * If the state machine asks for a short delay, then shorten
+	 * the timer timeout.
+	 */
+	if (smi_result == SI_SM_CALL_WITH_DELAY) {
+		smi_inc_stat(smi_info, short_timeouts);
+		timeout = jiffies + 1;
+	} else {
+		smi_inc_stat(smi_info, long_timeouts);
+		timeout = jiffies + SI_TIMEOUT_JIFFIES;
+	}
+
+do_mod_timer:
+	if (smi_result != SI_SM_IDLE)
+		smi_mod_timer(smi_info, timeout);
+	else
+		smi_info->timer_running = false;
+	spin_unlock_irqrestore(&(smi_info->si_lock), flags);
+}
+
+irqreturn_t ipmi_si_irq_handler(int irq, void *data)
+{
+	struct smi_info *smi_info = data;
+	unsigned long   flags;
+
+	if (smi_info->io.si_type == SI_BT)
+		/* We need to clear the IRQ flag for the BT interface. */
+		smi_info->io.outputb(&smi_info->io, IPMI_BT_INTMASK_REG,
+				     IPMI_BT_INTMASK_CLEAR_IRQ_BIT
+				     | IPMI_BT_INTMASK_ENABLE_IRQ_BIT);
+
+	spin_lock_irqsave(&(smi_info->si_lock), flags);
+
+	smi_inc_stat(smi_info, interrupts);
+
+	debug_timestamp(smi_info, "Interrupt");
+
+	smi_event_handler(smi_info, 0);
+	spin_unlock_irqrestore(&(smi_info->si_lock), flags);
+	return IRQ_HANDLED;
+}
+
+static int smi_start_processing(void            *send_info,
+				struct ipmi_smi *intf)
+{
+	struct smi_info *new_smi = send_info;
+	int             enable = 0;
+
+	new_smi->intf = intf;
+
+	/* Set up the timer that drives the interface. */
+	timer_setup(&new_smi->si_timer, smi_timeout, 0);
+	new_smi->timer_can_start = true;
+	smi_mod_timer(new_smi, jiffies + SI_TIMEOUT_JIFFIES);
+
+	/* Try to claim any interrupts. */
+	if (new_smi->io.irq_setup) {
+		new_smi->io.irq_handler_data = new_smi;
+		new_smi->io.irq_setup(&new_smi->io);
+	}
+
+	/*
+	 * Check if the user forcefully enabled the daemon.
+	 */
+	if (new_smi->si_num < num_force_kipmid)
+		enable = force_kipmid[new_smi->si_num];
+	/*
+	 * The BT interface is efficient enough to not need a thread,
+	 * and there is no need for a thread if we have interrupts.
+	 */
+	else if ((new_smi->io.si_type != SI_BT) && (!new_smi->io.irq))
+		enable = 1;
+
+	if (enable) {
+		new_smi->thread = kthread_run(ipmi_thread, new_smi,
+					      "kipmi%d", new_smi->si_num);
+		if (IS_ERR(new_smi->thread)) {
+			dev_notice(new_smi->io.dev,
+				   "Could not start kernel thread due to error %ld, only using timers to drive the interface\n",
+				   PTR_ERR(new_smi->thread));
+			new_smi->thread = NULL;
+		}
+	}
+
+	return 0;
+}
+
+static int get_smi_info(void *send_info, struct ipmi_smi_info *data)
+{
+	struct smi_info *smi = send_info;
+
+	data->addr_src = smi->io.addr_source;
+	data->dev = smi->io.dev;
+	data->addr_info = smi->io.addr_info;
+	get_device(smi->io.dev);
+
+	return 0;
+}
+
+static void set_maintenance_mode(void *send_info, bool enable)
+{
+	struct smi_info   *smi_info = send_info;
+
+	if (!enable)
+		atomic_set(&smi_info->req_events, 0);
+	smi_info->in_maintenance_mode = enable;
+}
+
+static void shutdown_smi(void *send_info);
+static const struct ipmi_smi_handlers handlers = {
+	.owner                  = THIS_MODULE,
+	.start_processing       = smi_start_processing,
+	.shutdown               = shutdown_smi,
+	.get_smi_info		= get_smi_info,
+	.sender			= sender,
+	.request_events		= request_events,
+	.set_need_watch		= set_need_watch,
+	.set_maintenance_mode   = set_maintenance_mode,
+	.set_run_to_completion  = set_run_to_completion,
+	.flush_messages		= flush_messages,
+	.poll			= poll,
+};
+
+static LIST_HEAD(smi_infos);
+static DEFINE_MUTEX(smi_infos_lock);
+static int smi_num; /* Used to sequence the SMIs */
+
+static const char * const addr_space_to_str[] = { "i/o", "mem" };
+
+module_param_array(force_kipmid, int, &num_force_kipmid, 0);
+MODULE_PARM_DESC(force_kipmid,
+		 "Force the kipmi daemon to be enabled (1) or disabled(0).  Normally the IPMI driver auto-detects this, but the value may be overridden by this parm.");
+module_param(unload_when_empty, bool, 0);
+MODULE_PARM_DESC(unload_when_empty,
+		 "Unload the module if no interfaces are specified or found, default is 1.  Setting to 0 is useful for hot add of devices using hotmod.");
+module_param_array(kipmid_max_busy_us, uint, &num_max_busy_us, 0644);
+MODULE_PARM_DESC(kipmid_max_busy_us,
+		 "Max time (in microseconds) to busy-wait for IPMI data before sleeping. 0 (default) means to wait forever. Set to 100-500 if kipmid is using up a lot of CPU time.");
+
+void ipmi_irq_finish_setup(struct si_sm_io *io)
+{
+	if (io->si_type == SI_BT)
+		/* Enable the interrupt in the BT interface. */
+		io->outputb(io, IPMI_BT_INTMASK_REG,
+			    IPMI_BT_INTMASK_ENABLE_IRQ_BIT);
+}
+
+void ipmi_irq_start_cleanup(struct si_sm_io *io)
+{
+	if (io->si_type == SI_BT)
+		/* Disable the interrupt in the BT interface. */
+		io->outputb(io, IPMI_BT_INTMASK_REG, 0);
+}
+
+static void std_irq_cleanup(struct si_sm_io *io)
+{
+	ipmi_irq_start_cleanup(io);
+	free_irq(io->irq, io->irq_handler_data);
+}
+
+int ipmi_std_irq_setup(struct si_sm_io *io)
+{
+	int rv;
+
+	if (!io->irq)
+		return 0;
+
+	rv = request_irq(io->irq,
+			 ipmi_si_irq_handler,
+			 IRQF_SHARED,
+			 SI_DEVICE_NAME,
+			 io->irq_handler_data);
+	if (rv) {
+		dev_warn(io->dev, "%s unable to claim interrupt %d, running polled\n",
+			 SI_DEVICE_NAME, io->irq);
+		io->irq = 0;
+	} else {
+		io->irq_cleanup = std_irq_cleanup;
+		ipmi_irq_finish_setup(io);
+		dev_info(io->dev, "Using irq %d\n", io->irq);
+	}
+
+	return rv;
+}
+
+static int wait_for_msg_done(struct smi_info *smi_info)
+{
+	enum si_sm_result     smi_result;
+
+	smi_result = smi_info->handlers->event(smi_info->si_sm, 0);
+	for (;;) {
+		if (smi_result == SI_SM_CALL_WITH_DELAY ||
+		    smi_result == SI_SM_CALL_WITH_TICK_DELAY) {
+			schedule_timeout_uninterruptible(1);
+			smi_result = smi_info->handlers->event(
+				smi_info->si_sm, jiffies_to_usecs(1));
+		} else if (smi_result == SI_SM_CALL_WITHOUT_DELAY) {
+			smi_result = smi_info->handlers->event(
+				smi_info->si_sm, 0);
+		} else
+			break;
+	}
+	if (smi_result == SI_SM_HOSED)
+		/*
+		 * We couldn't get the state machine to run, so whatever's at
+		 * the port is probably not an IPMI SMI interface.
+		 */
+		return -ENODEV;
+
+	return 0;
+}
+
+static int try_get_dev_id(struct smi_info *smi_info)
+{
+	unsigned char         msg[2];
+	unsigned char         *resp;
+	unsigned long         resp_len;
+	int                   rv = 0;
+	unsigned int          retry_count = 0;
+
+	resp = kmalloc(IPMI_MAX_MSG_LENGTH, GFP_KERNEL);
+	if (!resp)
+		return -ENOMEM;
+
+	/*
+	 * Do a Get Device ID command, since it comes back with some
+	 * useful info.
+	 */
+	msg[0] = IPMI_NETFN_APP_REQUEST << 2;
+	msg[1] = IPMI_GET_DEVICE_ID_CMD;
+
+retry:
+	smi_info->handlers->start_transaction(smi_info->si_sm, msg, 2);
+
+	rv = wait_for_msg_done(smi_info);
+	if (rv)
+		goto out;
+
+	resp_len = smi_info->handlers->get_result(smi_info->si_sm,
+						  resp, IPMI_MAX_MSG_LENGTH);
+
+	/* Check and record info from the get device id, in case we need it. */
+	rv = ipmi_demangle_device_id(resp[0] >> 2, resp[1],
+			resp + 2, resp_len - 2, &smi_info->device_id);
+	if (rv) {
+		/* record completion code */
+		unsigned char cc = *(resp + 2);
+
+		if (cc != IPMI_CC_NO_ERROR &&
+		    ++retry_count <= GET_DEVICE_ID_MAX_RETRY) {
+			dev_warn_ratelimited(smi_info->io.dev,
+			    "BMC returned 0x%2.2x, retry get bmc device id\n",
+			    cc);
+			goto retry;
+		}
+	}
+
+out:
+	kfree(resp);
+	return rv;
+}
+
+static int get_global_enables(struct smi_info *smi_info, u8 *enables)
+{
+	unsigned char         msg[3];
+	unsigned char         *resp;
+	unsigned long         resp_len;
+	int                   rv;
+
+	resp = kmalloc(IPMI_MAX_MSG_LENGTH, GFP_KERNEL);
+	if (!resp)
+		return -ENOMEM;
+
+	msg[0] = IPMI_NETFN_APP_REQUEST << 2;
+	msg[1] = IPMI_GET_BMC_GLOBAL_ENABLES_CMD;
+	smi_info->handlers->start_transaction(smi_info->si_sm, msg, 2);
+
+	rv = wait_for_msg_done(smi_info);
+	if (rv) {
+		dev_warn(smi_info->io.dev,
+			 "Error getting response from get global enables command: %d\n",
+			 rv);
+		goto out;
+	}
+
+	resp_len = smi_info->handlers->get_result(smi_info->si_sm,
+						  resp, IPMI_MAX_MSG_LENGTH);
+
+	if (resp_len < 4 ||
+			resp[0] != (IPMI_NETFN_APP_REQUEST | 1) << 2 ||
+			resp[1] != IPMI_GET_BMC_GLOBAL_ENABLES_CMD   ||
+			resp[2] != 0) {
+		dev_warn(smi_info->io.dev,
+			 "Invalid return from get global enables command: %ld %x %x %x\n",
+			 resp_len, resp[0], resp[1], resp[2]);
+		rv = -EINVAL;
+		goto out;
+	} else {
+		*enables = resp[3];
+	}
+
+out:
+	kfree(resp);
+	return rv;
+}
+
+/*
+ * Returns 1 if it gets an error from the command.
+ */
+static int set_global_enables(struct smi_info *smi_info, u8 enables)
+{
+	unsigned char         msg[3];
+	unsigned char         *resp;
+	unsigned long         resp_len;
+	int                   rv;
+
+	resp = kmalloc(IPMI_MAX_MSG_LENGTH, GFP_KERNEL);
+	if (!resp)
+		return -ENOMEM;
+
+	msg[0] = IPMI_NETFN_APP_REQUEST << 2;
+	msg[1] = IPMI_SET_BMC_GLOBAL_ENABLES_CMD;
+	msg[2] = enables;
+	smi_info->handlers->start_transaction(smi_info->si_sm, msg, 3);
+
+	rv = wait_for_msg_done(smi_info);
+	if (rv) {
+		dev_warn(smi_info->io.dev,
+			 "Error getting response from set global enables command: %d\n",
+			 rv);
+		goto out;
+	}
+
+	resp_len = smi_info->handlers->get_result(smi_info->si_sm,
+						  resp, IPMI_MAX_MSG_LENGTH);
+
+	if (resp_len < 3 ||
+			resp[0] != (IPMI_NETFN_APP_REQUEST | 1) << 2 ||
+			resp[1] != IPMI_SET_BMC_GLOBAL_ENABLES_CMD) {
+		dev_warn(smi_info->io.dev,
+			 "Invalid return from set global enables command: %ld %x %x\n",
+			 resp_len, resp[0], resp[1]);
+		rv = -EINVAL;
+		goto out;
+	}
+
+	if (resp[2] != 0)
+		rv = 1;
+
+out:
+	kfree(resp);
+	return rv;
+}
+
+/*
+ * Some BMCs do not support clearing the receive irq bit in the global
+ * enables (even if they don't support interrupts on the BMC).  Check
+ * for this and handle it properly.
+ */
+static void check_clr_rcv_irq(struct smi_info *smi_info)
+{
+	u8 enables = 0;
+	int rv;
+
+	rv = get_global_enables(smi_info, &enables);
+	if (!rv) {
+		if ((enables & IPMI_BMC_RCV_MSG_INTR) == 0)
+			/* Already clear, should work ok. */
+			return;
+
+		enables &= ~IPMI_BMC_RCV_MSG_INTR;
+		rv = set_global_enables(smi_info, enables);
+	}
+
+	if (rv < 0) {
+		dev_err(smi_info->io.dev,
+			"Cannot check clearing the rcv irq: %d\n", rv);
+		return;
+	}
+
+	if (rv) {
+		/*
+		 * An error when setting the event buffer bit means
+		 * clearing the bit is not supported.
+		 */
+		dev_warn(smi_info->io.dev,
+			 "The BMC does not support clearing the recv irq bit, compensating, but the BMC needs to be fixed.\n");
+		smi_info->cannot_disable_irq = true;
+	}
+}
+
+/*
+ * Some BMCs do not support setting the interrupt bits in the global
+ * enables even if they support interrupts.  Clearly bad, but we can
+ * compensate.
+ */
+static void check_set_rcv_irq(struct smi_info *smi_info)
+{
+	u8 enables = 0;
+	int rv;
+
+	if (!smi_info->io.irq)
+		return;
+
+	rv = get_global_enables(smi_info, &enables);
+	if (!rv) {
+		enables |= IPMI_BMC_RCV_MSG_INTR;
+		rv = set_global_enables(smi_info, enables);
+	}
+
+	if (rv < 0) {
+		dev_err(smi_info->io.dev,
+			"Cannot check setting the rcv irq: %d\n", rv);
+		return;
+	}
+
+	if (rv) {
+		/*
+		 * An error when setting the event buffer bit means
+		 * setting the bit is not supported.
+		 */
+		dev_warn(smi_info->io.dev,
+			 "The BMC does not support setting the recv irq bit, compensating, but the BMC needs to be fixed.\n");
+		smi_info->cannot_disable_irq = true;
+		smi_info->irq_enable_broken = true;
+	}
+}
+
+static int try_enable_event_buffer(struct smi_info *smi_info)
+{
+	unsigned char         msg[3];
+	unsigned char         *resp;
+	unsigned long         resp_len;
+	int                   rv = 0;
+
+	resp = kmalloc(IPMI_MAX_MSG_LENGTH, GFP_KERNEL);
+	if (!resp)
+		return -ENOMEM;
+
+	msg[0] = IPMI_NETFN_APP_REQUEST << 2;
+	msg[1] = IPMI_GET_BMC_GLOBAL_ENABLES_CMD;
+	smi_info->handlers->start_transaction(smi_info->si_sm, msg, 2);
+
+	rv = wait_for_msg_done(smi_info);
+	if (rv) {
+		pr_warn("Error getting response from get global enables command, the event buffer is not enabled\n");
+		goto out;
+	}
+
+	resp_len = smi_info->handlers->get_result(smi_info->si_sm,
+						  resp, IPMI_MAX_MSG_LENGTH);
+
+	if (resp_len < 4 ||
+			resp[0] != (IPMI_NETFN_APP_REQUEST | 1) << 2 ||
+			resp[1] != IPMI_GET_BMC_GLOBAL_ENABLES_CMD   ||
+			resp[2] != 0) {
+		pr_warn("Invalid return from get global enables command, cannot enable the event buffer\n");
+		rv = -EINVAL;
+		goto out;
+	}
+
+	if (resp[3] & IPMI_BMC_EVT_MSG_BUFF) {
+		/* buffer is already enabled, nothing to do. */
+		smi_info->supports_event_msg_buff = true;
+		goto out;
+	}
+
+	msg[0] = IPMI_NETFN_APP_REQUEST << 2;
+	msg[1] = IPMI_SET_BMC_GLOBAL_ENABLES_CMD;
+	msg[2] = resp[3] | IPMI_BMC_EVT_MSG_BUFF;
+	smi_info->handlers->start_transaction(smi_info->si_sm, msg, 3);
+
+	rv = wait_for_msg_done(smi_info);
+	if (rv) {
+		pr_warn("Error getting response from set global, enables command, the event buffer is not enabled\n");
+		goto out;
+	}
+
+	resp_len = smi_info->handlers->get_result(smi_info->si_sm,
+						  resp, IPMI_MAX_MSG_LENGTH);
+
+	if (resp_len < 3 ||
+			resp[0] != (IPMI_NETFN_APP_REQUEST | 1) << 2 ||
+			resp[1] != IPMI_SET_BMC_GLOBAL_ENABLES_CMD) {
+		pr_warn("Invalid return from get global, enables command, not enable the event buffer\n");
+		rv = -EINVAL;
+		goto out;
+	}
+
+	if (resp[2] != 0)
+		/*
+		 * An error when setting the event buffer bit means
+		 * that the event buffer is not supported.
+		 */
+		rv = -ENOENT;
+	else
+		smi_info->supports_event_msg_buff = true;
+
+out:
+	kfree(resp);
+	return rv;
+}
+
+#define IPMI_SI_ATTR(name) \
+static ssize_t name##_show(struct device *dev,			\
+			   struct device_attribute *attr,		\
+			   char *buf)					\
+{									\
+	struct smi_info *smi_info = dev_get_drvdata(dev);		\
+									\
+	return sysfs_emit(buf, "%u\n", smi_get_stat(smi_info, name));	\
+}									\
+static DEVICE_ATTR_RO(name)
+
+static ssize_t type_show(struct device *dev,
+			 struct device_attribute *attr,
+			 char *buf)
+{
+	struct smi_info *smi_info = dev_get_drvdata(dev);
+
+	return sysfs_emit(buf, "%s\n", si_to_str[smi_info->io.si_type]);
+}
+static DEVICE_ATTR_RO(type);
+
+static ssize_t interrupts_enabled_show(struct device *dev,
+				       struct device_attribute *attr,
+				       char *buf)
+{
+	struct smi_info *smi_info = dev_get_drvdata(dev);
+	int enabled = smi_info->io.irq && !smi_info->interrupt_disabled;
+
+	return sysfs_emit(buf, "%d\n", enabled);
+}
+static DEVICE_ATTR_RO(interrupts_enabled);
+
+IPMI_SI_ATTR(short_timeouts);
+IPMI_SI_ATTR(long_timeouts);
+IPMI_SI_ATTR(idles);
+IPMI_SI_ATTR(interrupts);
+IPMI_SI_ATTR(attentions);
+IPMI_SI_ATTR(flag_fetches);
+IPMI_SI_ATTR(hosed_count);
+IPMI_SI_ATTR(complete_transactions);
+IPMI_SI_ATTR(events);
+IPMI_SI_ATTR(watchdog_pretimeouts);
+IPMI_SI_ATTR(incoming_messages);
+
+static ssize_t params_show(struct device *dev,
+			   struct device_attribute *attr,
+			   char *buf)
+{
+	struct smi_info *smi_info = dev_get_drvdata(dev);
+
+	return sysfs_emit(buf,
+			"%s,%s,0x%lx,rsp=%d,rsi=%d,rsh=%d,irq=%d,ipmb=%d\n",
+			si_to_str[smi_info->io.si_type],
+			addr_space_to_str[smi_info->io.addr_space],
+			smi_info->io.addr_data,
+			smi_info->io.regspacing,
+			smi_info->io.regsize,
+			smi_info->io.regshift,
+			smi_info->io.irq,
+			smi_info->io.slave_addr);
+}
+static DEVICE_ATTR_RO(params);
+
+static struct attribute *ipmi_si_dev_attrs[] = {
+	&dev_attr_type.attr,
+	&dev_attr_interrupts_enabled.attr,
+	&dev_attr_short_timeouts.attr,
+	&dev_attr_long_timeouts.attr,
+	&dev_attr_idles.attr,
+	&dev_attr_interrupts.attr,
+	&dev_attr_attentions.attr,
+	&dev_attr_flag_fetches.attr,
+	&dev_attr_hosed_count.attr,
+	&dev_attr_complete_transactions.attr,
+	&dev_attr_events.attr,
+	&dev_attr_watchdog_pretimeouts.attr,
+	&dev_attr_incoming_messages.attr,
+	&dev_attr_params.attr,
+	NULL
+};
+
+static const struct attribute_group ipmi_si_dev_attr_group = {
+	.attrs		= ipmi_si_dev_attrs,
+};
+
+/*
+ * oem_data_avail_to_receive_msg_avail
+ * @info - smi_info structure with msg_flags set
+ *
+ * Converts flags from OEM_DATA_AVAIL to RECEIVE_MSG_AVAIL
+ * Returns 1 indicating need to re-run handle_flags().
+ */
+static int oem_data_avail_to_receive_msg_avail(struct smi_info *smi_info)
+{
+	smi_info->msg_flags = ((smi_info->msg_flags & ~OEM_DATA_AVAIL) |
+			       RECEIVE_MSG_AVAIL);
+	return 1;
+}
+
+/*
+ * setup_dell_poweredge_oem_data_handler
+ * @info - smi_info.device_id must be populated
+ *
+ * Systems that match, but have firmware version < 1.40 may assert
+ * OEM0_DATA_AVAIL on their own, without being told via Set Flags that
+ * it's safe to do so.  Such systems will de-assert OEM1_DATA_AVAIL
+ * upon receipt of IPMI_GET_MSG_CMD, so we should treat these flags
+ * as RECEIVE_MSG_AVAIL instead.
+ *
+ * As Dell has no plans to release IPMI 1.5 firmware that *ever*
+ * assert the OEM[012] bits, and if it did, the driver would have to
+ * change to handle that properly, we don't actually check for the
+ * firmware version.
+ * Device ID = 0x20                BMC on PowerEdge 8G servers
+ * Device Revision = 0x80
+ * Firmware Revision1 = 0x01       BMC version 1.40
+ * Firmware Revision2 = 0x40       BCD encoded
+ * IPMI Version = 0x51             IPMI 1.5
+ * Manufacturer ID = A2 02 00      Dell IANA
+ *
+ * Additionally, PowerEdge systems with IPMI < 1.5 may also assert
+ * OEM0_DATA_AVAIL and needs to be treated as RECEIVE_MSG_AVAIL.
+ *
+ */
+#define DELL_POWEREDGE_8G_BMC_DEVICE_ID  0x20
+#define DELL_POWEREDGE_8G_BMC_DEVICE_REV 0x80
+#define DELL_POWEREDGE_8G_BMC_IPMI_VERSION 0x51
+#define DELL_IANA_MFR_ID 0x0002a2
+static void setup_dell_poweredge_oem_data_handler(struct smi_info *smi_info)
+{
+	struct ipmi_device_id *id = &smi_info->device_id;
+	if (id->manufacturer_id == DELL_IANA_MFR_ID) {
+		if (id->device_id       == DELL_POWEREDGE_8G_BMC_DEVICE_ID  &&
+		    id->device_revision == DELL_POWEREDGE_8G_BMC_DEVICE_REV &&
+		    id->ipmi_version   == DELL_POWEREDGE_8G_BMC_IPMI_VERSION) {
+			smi_info->oem_data_avail_handler =
+				oem_data_avail_to_receive_msg_avail;
+		} else if (ipmi_version_major(id) < 1 ||
+			   (ipmi_version_major(id) == 1 &&
+			    ipmi_version_minor(id) < 5)) {
+			smi_info->oem_data_avail_handler =
+				oem_data_avail_to_receive_msg_avail;
+		}
+	}
+}
+
+#define CANNOT_RETURN_REQUESTED_LENGTH 0xCA
+static void return_hosed_msg_badsize(struct smi_info *smi_info)
+{
+	struct ipmi_smi_msg *msg = smi_info->curr_msg;
+
+	/* Make it a response */
+	msg->rsp[0] = msg->data[0] | 4;
+	msg->rsp[1] = msg->data[1];
+	msg->rsp[2] = CANNOT_RETURN_REQUESTED_LENGTH;
+	msg->rsp_size = 3;
+	smi_info->curr_msg = NULL;
+	deliver_recv_msg(smi_info, msg);
+}
+
+/*
+ * dell_poweredge_bt_xaction_handler
+ * @info - smi_info.device_id must be populated
+ *
+ * Dell PowerEdge servers with the BT interface (x6xx and 1750) will
+ * not respond to a Get SDR command if the length of the data
+ * requested is exactly 0x3A, which leads to command timeouts and no
+ * data returned.  This intercepts such commands, and causes userspace
+ * callers to try again with a different-sized buffer, which succeeds.
+ */
+
+#define STORAGE_NETFN 0x0A
+#define STORAGE_CMD_GET_SDR 0x23
+static int dell_poweredge_bt_xaction_handler(struct notifier_block *self,
+					     unsigned long unused,
+					     void *in)
+{
+	struct smi_info *smi_info = in;
+	unsigned char *data = smi_info->curr_msg->data;
+	unsigned int size   = smi_info->curr_msg->data_size;
+	if (size >= 8 &&
+	    (data[0]>>2) == STORAGE_NETFN &&
+	    data[1] == STORAGE_CMD_GET_SDR &&
+	    data[7] == 0x3A) {
+		return_hosed_msg_badsize(smi_info);
+		return NOTIFY_STOP;
+	}
+	return NOTIFY_DONE;
+}
+
+static struct notifier_block dell_poweredge_bt_xaction_notifier = {
+	.notifier_call	= dell_poweredge_bt_xaction_handler,
+};
+
+/*
+ * setup_dell_poweredge_bt_xaction_handler
+ * @info - smi_info.device_id must be filled in already
+ *
+ * Fills in smi_info.device_id.start_transaction_pre_hook
+ * when we know what function to use there.
+ */
+static void
+setup_dell_poweredge_bt_xaction_handler(struct smi_info *smi_info)
+{
+	struct ipmi_device_id *id = &smi_info->device_id;
+	if (id->manufacturer_id == DELL_IANA_MFR_ID &&
+	    smi_info->io.si_type == SI_BT)
+		register_xaction_notifier(&dell_poweredge_bt_xaction_notifier);
+}
+
+/*
+ * setup_oem_data_handler
+ * @info - smi_info.device_id must be filled in already
+ *
+ * Fills in smi_info.device_id.oem_data_available_handler
+ * when we know what function to use there.
+ */
+
+static void setup_oem_data_handler(struct smi_info *smi_info)
+{
+	setup_dell_poweredge_oem_data_handler(smi_info);
+}
+
+static void setup_xaction_handlers(struct smi_info *smi_info)
+{
+	setup_dell_poweredge_bt_xaction_handler(smi_info);
+}
+
+static void check_for_broken_irqs(struct smi_info *smi_info)
+{
+	check_clr_rcv_irq(smi_info);
+	check_set_rcv_irq(smi_info);
+}
+
+static inline void stop_timer_and_thread(struct smi_info *smi_info)
+{
+	if (smi_info->thread != NULL) {
+		kthread_stop(smi_info->thread);
+		smi_info->thread = NULL;
+	}
+
+	smi_info->timer_can_start = false;
+	del_timer_sync(&smi_info->si_timer);
+}
+
+static struct smi_info *find_dup_si(struct smi_info *info)
+{
+	struct smi_info *e;
+
+	list_for_each_entry(e, &smi_infos, link) {
+		if (e->io.addr_space != info->io.addr_space)
+			continue;
+		if (e->io.addr_data == info->io.addr_data) {
+			/*
+			 * This is a cheap hack, ACPI doesn't have a defined
+			 * slave address but SMBIOS does.  Pick it up from
+			 * any source that has it available.
+			 */
+			if (info->io.slave_addr && !e->io.slave_addr)
+				e->io.slave_addr = info->io.slave_addr;
+			return e;
+		}
+	}
+
+	return NULL;
+}
+
+int ipmi_si_add_smi(struct si_sm_io *io)
+{
+	int rv = 0;
+	struct smi_info *new_smi, *dup;
+
+	/*
+	 * If the user gave us a hard-coded device at the same
+	 * address, they presumably want us to use it and not what is
+	 * in the firmware.
+	 */
+	if (io->addr_source != SI_HARDCODED && io->addr_source != SI_HOTMOD &&
+	    ipmi_si_hardcode_match(io->addr_space, io->addr_data)) {
+		dev_info(io->dev,
+			 "Hard-coded device at this address already exists");
+		return -ENODEV;
+	}
+
+	if (!io->io_setup) {
+		if (io->addr_space == IPMI_IO_ADDR_SPACE) {
+			io->io_setup = ipmi_si_port_setup;
+		} else if (io->addr_space == IPMI_MEM_ADDR_SPACE) {
+			io->io_setup = ipmi_si_mem_setup;
+		} else {
+			return -EINVAL;
+		}
+	}
+
+	new_smi = kzalloc(sizeof(*new_smi), GFP_KERNEL);
+	if (!new_smi)
+		return -ENOMEM;
+	spin_lock_init(&new_smi->si_lock);
+
+	new_smi->io = *io;
+
+	mutex_lock(&smi_infos_lock);
+	dup = find_dup_si(new_smi);
+	if (dup) {
+		if (new_smi->io.addr_source == SI_ACPI &&
+		    dup->io.addr_source == SI_SMBIOS) {
+			/* We prefer ACPI over SMBIOS. */
+			dev_info(dup->io.dev,
+				 "Removing SMBIOS-specified %s state machine in favor of ACPI\n",
+				 si_to_str[new_smi->io.si_type]);
+			cleanup_one_si(dup);
+		} else {
+			dev_info(new_smi->io.dev,
+				 "%s-specified %s state machine: duplicate\n",
+				 ipmi_addr_src_to_str(new_smi->io.addr_source),
+				 si_to_str[new_smi->io.si_type]);
+			rv = -EBUSY;
+			kfree(new_smi);
+			goto out_err;
+		}
+	}
+
+	pr_info("Adding %s-specified %s state machine\n",
+		ipmi_addr_src_to_str(new_smi->io.addr_source),
+		si_to_str[new_smi->io.si_type]);
+
+	list_add_tail(&new_smi->link, &smi_infos);
+
+	if (initialized)
+		rv = try_smi_init(new_smi);
+out_err:
+	mutex_unlock(&smi_infos_lock);
+	return rv;
+}
+
+/*
+ * Try to start up an interface.  Must be called with smi_infos_lock
+ * held, primarily to keep smi_num consistent, we only one to do these
+ * one at a time.
+ */
+static int try_smi_init(struct smi_info *new_smi)
+{
+	int rv = 0;
+	int i;
+
+	pr_info("Trying %s-specified %s state machine at %s address 0x%lx, slave address 0x%x, irq %d\n",
+		ipmi_addr_src_to_str(new_smi->io.addr_source),
+		si_to_str[new_smi->io.si_type],
+		addr_space_to_str[new_smi->io.addr_space],
+		new_smi->io.addr_data,
+		new_smi->io.slave_addr, new_smi->io.irq);
+
+	switch (new_smi->io.si_type) {
+	case SI_KCS:
+		new_smi->handlers = &kcs_smi_handlers;
+		break;
+
+	case SI_SMIC:
+		new_smi->handlers = &smic_smi_handlers;
+		break;
+
+	case SI_BT:
+		new_smi->handlers = &bt_smi_handlers;
+		break;
+
+	default:
+		/* No support for anything else yet. */
+		rv = -EIO;
+		goto out_err;
+	}
+
+	new_smi->si_num = smi_num;
+
+	/* Do this early so it's available for logs. */
+	if (!new_smi->io.dev) {
+		pr_err("IPMI interface added with no device\n");
+		rv = -EIO;
+		goto out_err;
+	}
+
+	/* Allocate the state machine's data and initialize it. */
+	new_smi->si_sm = kmalloc(new_smi->handlers->size(), GFP_KERNEL);
+	if (!new_smi->si_sm) {
+		rv = -ENOMEM;
+		goto out_err;
+	}
+	new_smi->io.io_size = new_smi->handlers->init_data(new_smi->si_sm,
+							   &new_smi->io);
+
+	/* Now that we know the I/O size, we can set up the I/O. */
+	rv = new_smi->io.io_setup(&new_smi->io);
+	if (rv) {
+		dev_err(new_smi->io.dev, "Could not set up I/O space\n");
+		goto out_err;
+	}
+
+	/* Do low-level detection first. */
+	if (new_smi->handlers->detect(new_smi->si_sm)) {
+		if (new_smi->io.addr_source)
+			dev_err(new_smi->io.dev,
+				"Interface detection failed\n");
+		rv = -ENODEV;
+		goto out_err;
+	}
+
+	/*
+	 * Attempt a get device id command.  If it fails, we probably
+	 * don't have a BMC here.
+	 */
+	rv = try_get_dev_id(new_smi);
+	if (rv) {
+		if (new_smi->io.addr_source)
+			dev_err(new_smi->io.dev,
+			       "There appears to be no BMC at this location\n");
+		goto out_err;
+	}
+
+	setup_oem_data_handler(new_smi);
+	setup_xaction_handlers(new_smi);
+	check_for_broken_irqs(new_smi);
+
+	new_smi->waiting_msg = NULL;
+	new_smi->curr_msg = NULL;
+	atomic_set(&new_smi->req_events, 0);
+	new_smi->run_to_completion = false;
+	for (i = 0; i < SI_NUM_STATS; i++)
+		atomic_set(&new_smi->stats[i], 0);
+
+	new_smi->interrupt_disabled = true;
+	atomic_set(&new_smi->need_watch, 0);
+
+	rv = try_enable_event_buffer(new_smi);
+	if (rv == 0)
+		new_smi->has_event_buffer = true;
+
+	/*
+	 * Start clearing the flags before we enable interrupts or the
+	 * timer to avoid racing with the timer.
+	 */
+	start_clear_flags(new_smi);
+
+	/*
+	 * IRQ is defined to be set when non-zero.  req_events will
+	 * cause a global flags check that will enable interrupts.
+	 */
+	if (new_smi->io.irq) {
+		new_smi->interrupt_disabled = false;
+		atomic_set(&new_smi->req_events, 1);
+	}
+
+	dev_set_drvdata(new_smi->io.dev, new_smi);
+	rv = device_add_group(new_smi->io.dev, &ipmi_si_dev_attr_group);
+	if (rv) {
+		dev_err(new_smi->io.dev,
+			"Unable to add device attributes: error %d\n",
+			rv);
+		goto out_err;
+	}
+	new_smi->dev_group_added = true;
+
+	rv = ipmi_register_smi(&handlers,
+			       new_smi,
+			       new_smi->io.dev,
+			       new_smi->io.slave_addr);
+	if (rv) {
+		dev_err(new_smi->io.dev,
+			"Unable to register device: error %d\n",
+			rv);
+		goto out_err;
+	}
+
+	/* Don't increment till we know we have succeeded. */
+	smi_num++;
+
+	dev_info(new_smi->io.dev, "IPMI %s interface initialized\n",
+		 si_to_str[new_smi->io.si_type]);
+
+	WARN_ON(new_smi->io.dev->init_name != NULL);
+
+ out_err:
+	if (rv && new_smi->io.io_cleanup) {
+		new_smi->io.io_cleanup(&new_smi->io);
+		new_smi->io.io_cleanup = NULL;
+	}
+
+	if (rv && new_smi->si_sm) {
+		kfree(new_smi->si_sm);
+		new_smi->si_sm = NULL;
+	}
+
+	return rv;
+}
+
+static int __init init_ipmi_si(void)
+{
+	struct smi_info *e;
+	enum ipmi_addr_src type = SI_INVALID;
+
+	if (initialized)
+		return 0;
+
+	ipmi_hardcode_init();
+
+	pr_info("IPMI System Interface driver\n");
+
+	ipmi_si_platform_init();
+
+	ipmi_si_pci_init();
+
+	ipmi_si_parisc_init();
+
+	/* We prefer devices with interrupts, but in the case of a machine
+	   with multiple BMCs we assume that there will be several instances
+	   of a given type so if we succeed in registering a type then also
+	   try to register everything else of the same type */
+	mutex_lock(&smi_infos_lock);
+	list_for_each_entry(e, &smi_infos, link) {
+		/* Try to register a device if it has an IRQ and we either
+		   haven't successfully registered a device yet or this
+		   device has the same type as one we successfully registered */
+		if (e->io.irq && (!type || e->io.addr_source == type)) {
+			if (!try_smi_init(e)) {
+				type = e->io.addr_source;
+			}
+		}
+	}
+
+	/* type will only have been set if we successfully registered an si */
+	if (type)
+		goto skip_fallback_noirq;
+
+	/* Fall back to the preferred device */
+
+	list_for_each_entry(e, &smi_infos, link) {
+		if (!e->io.irq && (!type || e->io.addr_source == type)) {
+			if (!try_smi_init(e)) {
+				type = e->io.addr_source;
+			}
+		}
+	}
+
+skip_fallback_noirq:
+	initialized = true;
+	mutex_unlock(&smi_infos_lock);
+
+	if (type)
+		return 0;
+
+	mutex_lock(&smi_infos_lock);
+	if (unload_when_empty && list_empty(&smi_infos)) {
+		mutex_unlock(&smi_infos_lock);
+		cleanup_ipmi_si();
+		pr_warn("Unable to find any System Interface(s)\n");
+		return -ENODEV;
+	} else {
+		mutex_unlock(&smi_infos_lock);
+		return 0;
+	}
+}
+module_init(init_ipmi_si);
+
+static void wait_msg_processed(struct smi_info *smi_info)
+{
+	unsigned long jiffies_now;
+	long time_diff;
+
+	while (smi_info->curr_msg || (smi_info->si_state != SI_NORMAL)) {
+		jiffies_now = jiffies;
+		time_diff = (((long)jiffies_now - (long)smi_info->last_timeout_jiffies)
+		     * SI_USEC_PER_JIFFY);
+		smi_event_handler(smi_info, time_diff);
+		schedule_timeout_uninterruptible(1);
+	}
+}
+
+static void shutdown_smi(void *send_info)
+{
+	struct smi_info *smi_info = send_info;
+
+	if (smi_info->dev_group_added) {
+		device_remove_group(smi_info->io.dev, &ipmi_si_dev_attr_group);
+		smi_info->dev_group_added = false;
+	}
+	if (smi_info->io.dev)
+		dev_set_drvdata(smi_info->io.dev, NULL);
+
+	/*
+	 * Make sure that interrupts, the timer and the thread are
+	 * stopped and will not run again.
+	 */
+	smi_info->interrupt_disabled = true;
+	if (smi_info->io.irq_cleanup) {
+		smi_info->io.irq_cleanup(&smi_info->io);
+		smi_info->io.irq_cleanup = NULL;
+	}
+	stop_timer_and_thread(smi_info);
+
+	/*
+	 * Wait until we know that we are out of any interrupt
+	 * handlers might have been running before we freed the
+	 * interrupt.
+	 */
+	synchronize_rcu();
+
+	/*
+	 * Timeouts are stopped, now make sure the interrupts are off
+	 * in the BMC.  Note that timers and CPU interrupts are off,
+	 * so no need for locks.
+	 */
+	wait_msg_processed(smi_info);
+
+	if (smi_info->handlers)
+		disable_si_irq(smi_info);
+
+	wait_msg_processed(smi_info);
+
+	if (smi_info->handlers)
+		smi_info->handlers->cleanup(smi_info->si_sm);
+
+	if (smi_info->io.io_cleanup) {
+		smi_info->io.io_cleanup(&smi_info->io);
+		smi_info->io.io_cleanup = NULL;
+	}
+
+	kfree(smi_info->si_sm);
+	smi_info->si_sm = NULL;
+
+	smi_info->intf = NULL;
+}
+
+/*
+ * Must be called with smi_infos_lock held, to serialize the
+ * smi_info->intf check.
+ */
+static void cleanup_one_si(struct smi_info *smi_info)
+{
+	if (!smi_info)
+		return;
+
+	list_del(&smi_info->link);
+	ipmi_unregister_smi(smi_info->intf);
+	kfree(smi_info);
+}
+
+void ipmi_si_remove_by_dev(struct device *dev)
+{
+	struct smi_info *e;
+
+	mutex_lock(&smi_infos_lock);
+	list_for_each_entry(e, &smi_infos, link) {
+		if (e->io.dev == dev) {
+			cleanup_one_si(e);
+			break;
+		}
+	}
+	mutex_unlock(&smi_infos_lock);
+}
+
+struct device *ipmi_si_remove_by_data(int addr_space, enum si_type si_type,
+				      unsigned long addr)
+{
+	/* remove */
+	struct smi_info *e, *tmp_e;
+	struct device *dev = NULL;
+
+	mutex_lock(&smi_infos_lock);
+	list_for_each_entry_safe(e, tmp_e, &smi_infos, link) {
+		if (e->io.addr_space != addr_space)
+			continue;
+		if (e->io.si_type != si_type)
+			continue;
+		if (e->io.addr_data == addr) {
+			dev = get_device(e->io.dev);
+			cleanup_one_si(e);
+		}
+	}
+	mutex_unlock(&smi_infos_lock);
+
+	return dev;
+}
+
+static void cleanup_ipmi_si(void)
+{
+	struct smi_info *e, *tmp_e;
+
+	if (!initialized)
+		return;
+
+	ipmi_si_pci_shutdown();
+
+	ipmi_si_parisc_shutdown();
+
+	ipmi_si_platform_shutdown();
+
+	mutex_lock(&smi_infos_lock);
+	list_for_each_entry_safe(e, tmp_e, &smi_infos, link)
+		cleanup_one_si(e);
+	mutex_unlock(&smi_infos_lock);
+
+	ipmi_si_hardcode_exit();
+	ipmi_si_hotmod_exit();
+}
+module_exit(cleanup_ipmi_si);
+
+MODULE_ALIAS("platform:dmi-ipmi-si");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Corey Minyard <minyard@mvista.com>");
+MODULE_DESCRIPTION("Interface to the IPMI driver for the KCS, SMIC, and BT system interfaces.");