Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-next
[cascardo/linux.git] / drivers / acpi / acpi_ipmi.c
index a6977e1..ac0f52f 100644 (file)
@@ -1,8 +1,9 @@
 /*
  *  acpi_ipmi.c - ACPI IPMI opregion
  *
- *  Copyright (C) 2010 Intel Corporation
- *  Copyright (C) 2010 Zhao Yakui <yakui.zhao@intel.com>
+ *  Copyright (C) 2010, 2013 Intel Corporation
+ *    Author: Zhao Yakui <yakui.zhao@intel.com>
+ *            Lv Zheng <lv.zheng@intel.com>
  *
  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  *
  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  */
 
-#include <linux/kernel.h>
 #include <linux/module.h>
-#include <linux/init.h>
-#include <linux/types.h>
-#include <linux/delay.h>
-#include <linux/proc_fs.h>
-#include <linux/seq_file.h>
-#include <linux/interrupt.h>
-#include <linux/list.h>
-#include <linux/spinlock.h>
-#include <linux/io.h>
-#include <acpi/acpi_bus.h>
-#include <acpi/acpi_drivers.h>
+#include <linux/acpi.h>
 #include <linux/ipmi.h>
-#include <linux/device.h>
-#include <linux/pnp.h>
 #include <linux/spinlock.h>
 
 MODULE_AUTHOR("Zhao Yakui");
 MODULE_DESCRIPTION("ACPI IPMI Opregion driver");
 MODULE_LICENSE("GPL");
 
-#define IPMI_FLAGS_HANDLER_INSTALL     0
-
 #define ACPI_IPMI_OK                   0
 #define ACPI_IPMI_TIMEOUT              0x10
 #define ACPI_IPMI_UNKNOWN              0x07
 /* the IPMI timeout is 5s */
-#define IPMI_TIMEOUT                   (5 * HZ)
+#define IPMI_TIMEOUT                   (5000)
+#define ACPI_IPMI_MAX_MSG_LENGTH       64
 
 struct acpi_ipmi_device {
        /* the device list attached to driver_data.ipmi_devices */
        struct list_head head;
+
        /* the IPMI request message list */
        struct list_head tx_msg_list;
-       spinlock_t      tx_msg_lock;
+
+       spinlock_t tx_msg_lock;
        acpi_handle handle;
-       struct pnp_dev *pnp_dev;
-       ipmi_user_t     user_interface;
+       struct device *dev;
+       ipmi_user_t user_interface;
        int ipmi_ifnum; /* IPMI interface number */
        long curr_msgid;
-       unsigned long flags;
-       struct ipmi_smi_info smi_data;
+       bool dead;
+       struct kref kref;
 };
 
 struct ipmi_driver_data {
-       struct list_head        ipmi_devices;
-       struct ipmi_smi_watcher bmc_events;
-       struct ipmi_user_hndl   ipmi_hndlrs;
-       struct mutex            ipmi_lock;
+       struct list_head ipmi_devices;
+       struct ipmi_smi_watcher bmc_events;
+       struct ipmi_user_hndl ipmi_hndlrs;
+       struct mutex ipmi_lock;
+
+       /*
+        * NOTE: IPMI System Interface Selection
+        * There is no system interface specified by the IPMI operation
+        * region access.  We try to select one system interface with ACPI
+        * handle set.  IPMI messages passed from the ACPI codes are sent
+        * to this selected global IPMI system interface.
+        */
+       struct acpi_ipmi_device *selected_smi;
 };
 
 struct acpi_ipmi_msg {
        struct list_head head;
+
        /*
         * General speaking the addr type should be SI_ADDR_TYPE. And
         * the addr channel should be BMC.
@@ -86,30 +85,31 @@ struct acpi_ipmi_msg {
         */
        struct ipmi_addr addr;
        long tx_msgid;
+
        /* it is used to track whether the IPMI message is finished */
        struct completion tx_complete;
+
        struct kernel_ipmi_msg tx_message;
-       int     msg_done;
-       /* tx data . And copy it from ACPI object buffer */
-       u8      tx_data[64];
-       int     tx_len;
-       u8      rx_data[64];
-       int     rx_len;
+       int msg_done;
+
+       /* tx/rx data . And copy it from/to ACPI object buffer */
+       u8 data[ACPI_IPMI_MAX_MSG_LENGTH];
+       u8 rx_len;
+
        struct acpi_ipmi_device *device;
+       struct kref kref;
 };
 
 /* IPMI request/response buffer per ACPI 4.0, sec 5.5.2.4.3.2 */
 struct acpi_ipmi_buffer {
        u8 status;
        u8 length;
-       u8 data[64];
+       u8 data[ACPI_IPMI_MAX_MSG_LENGTH];
 };
 
 static void ipmi_register_bmc(int iface, struct device *dev);
 static void ipmi_bmc_gone(int iface);
 static void ipmi_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data);
-static void acpi_add_ipmi_device(struct acpi_ipmi_device *ipmi_device);
-static void acpi_remove_ipmi_device(struct acpi_ipmi_device *ipmi_device);
 
 static struct ipmi_driver_data driver_data = {
        .ipmi_devices = LIST_HEAD_INIT(driver_data.ipmi_devices),
@@ -121,29 +121,142 @@ static struct ipmi_driver_data driver_data = {
        .ipmi_hndlrs = {
                .ipmi_recv_hndl = ipmi_msg_handler,
        },
+       .ipmi_lock = __MUTEX_INITIALIZER(driver_data.ipmi_lock)
 };
 
-static struct acpi_ipmi_msg *acpi_alloc_ipmi_msg(struct acpi_ipmi_device *ipmi)
+static struct acpi_ipmi_device *
+ipmi_dev_alloc(int iface, struct device *dev, acpi_handle handle)
+{
+       struct acpi_ipmi_device *ipmi_device;
+       int err;
+       ipmi_user_t user;
+
+       ipmi_device = kzalloc(sizeof(*ipmi_device), GFP_KERNEL);
+       if (!ipmi_device)
+               return NULL;
+
+       kref_init(&ipmi_device->kref);
+       INIT_LIST_HEAD(&ipmi_device->head);
+       INIT_LIST_HEAD(&ipmi_device->tx_msg_list);
+       spin_lock_init(&ipmi_device->tx_msg_lock);
+       ipmi_device->handle = handle;
+       ipmi_device->dev = get_device(dev);
+       ipmi_device->ipmi_ifnum = iface;
+
+       err = ipmi_create_user(iface, &driver_data.ipmi_hndlrs,
+                              ipmi_device, &user);
+       if (err) {
+               put_device(dev);
+               kfree(ipmi_device);
+               return NULL;
+       }
+       ipmi_device->user_interface = user;
+
+       return ipmi_device;
+}
+
+static void ipmi_dev_release(struct acpi_ipmi_device *ipmi_device)
+{
+       ipmi_destroy_user(ipmi_device->user_interface);
+       put_device(ipmi_device->dev);
+       kfree(ipmi_device);
+}
+
+static void ipmi_dev_release_kref(struct kref *kref)
+{
+       struct acpi_ipmi_device *ipmi =
+               container_of(kref, struct acpi_ipmi_device, kref);
+
+       ipmi_dev_release(ipmi);
+}
+
+static void __ipmi_dev_kill(struct acpi_ipmi_device *ipmi_device)
+{
+       list_del(&ipmi_device->head);
+       if (driver_data.selected_smi == ipmi_device)
+               driver_data.selected_smi = NULL;
+
+       /*
+        * Always setting dead flag after deleting from the list or
+        * list_for_each_entry() codes must get changed.
+        */
+       ipmi_device->dead = true;
+}
+
+static struct acpi_ipmi_device *acpi_ipmi_dev_get(void)
+{
+       struct acpi_ipmi_device *ipmi_device = NULL;
+
+       mutex_lock(&driver_data.ipmi_lock);
+       if (driver_data.selected_smi) {
+               ipmi_device = driver_data.selected_smi;
+               kref_get(&ipmi_device->kref);
+       }
+       mutex_unlock(&driver_data.ipmi_lock);
+
+       return ipmi_device;
+}
+
+static void acpi_ipmi_dev_put(struct acpi_ipmi_device *ipmi_device)
+{
+       kref_put(&ipmi_device->kref, ipmi_dev_release_kref);
+}
+
+static struct acpi_ipmi_msg *ipmi_msg_alloc(void)
 {
+       struct acpi_ipmi_device *ipmi;
        struct acpi_ipmi_msg *ipmi_msg;
-       struct pnp_dev *pnp_dev = ipmi->pnp_dev;
+
+       ipmi = acpi_ipmi_dev_get();
+       if (!ipmi)
+               return NULL;
 
        ipmi_msg = kzalloc(sizeof(struct acpi_ipmi_msg), GFP_KERNEL);
-       if (!ipmi_msg)  {
-               dev_warn(&pnp_dev->dev, "Can't allocate memory for ipmi_msg\n");
+       if (!ipmi_msg) {
+               acpi_ipmi_dev_put(ipmi);
                return NULL;
        }
+
+       kref_init(&ipmi_msg->kref);
        init_completion(&ipmi_msg->tx_complete);
        INIT_LIST_HEAD(&ipmi_msg->head);
        ipmi_msg->device = ipmi;
+       ipmi_msg->msg_done = ACPI_IPMI_UNKNOWN;
+
        return ipmi_msg;
 }
 
-#define                IPMI_OP_RGN_NETFN(offset)       ((offset >> 8) & 0xff)
-#define                IPMI_OP_RGN_CMD(offset)         (offset & 0xff)
-static void acpi_format_ipmi_msg(struct acpi_ipmi_msg *tx_msg,
-                               acpi_physical_address address,
-                               acpi_integer *value)
+static void ipmi_msg_release(struct acpi_ipmi_msg *tx_msg)
+{
+       acpi_ipmi_dev_put(tx_msg->device);
+       kfree(tx_msg);
+}
+
+static void ipmi_msg_release_kref(struct kref *kref)
+{
+       struct acpi_ipmi_msg *tx_msg =
+               container_of(kref, struct acpi_ipmi_msg, kref);
+
+       ipmi_msg_release(tx_msg);
+}
+
+static struct acpi_ipmi_msg *acpi_ipmi_msg_get(struct acpi_ipmi_msg *tx_msg)
+{
+       kref_get(&tx_msg->kref);
+
+       return tx_msg;
+}
+
+static void acpi_ipmi_msg_put(struct acpi_ipmi_msg *tx_msg)
+{
+       kref_put(&tx_msg->kref, ipmi_msg_release_kref);
+}
+
+#define IPMI_OP_RGN_NETFN(offset)      ((offset >> 8) & 0xff)
+#define IPMI_OP_RGN_CMD(offset)                (offset & 0xff)
+static int acpi_format_ipmi_request(struct acpi_ipmi_msg *tx_msg,
+                                   acpi_physical_address address,
+                                   acpi_integer *value)
 {
        struct kernel_ipmi_msg *msg;
        struct acpi_ipmi_buffer *buffer;
@@ -151,21 +264,31 @@ static void acpi_format_ipmi_msg(struct acpi_ipmi_msg *tx_msg,
        unsigned long flags;
 
        msg = &tx_msg->tx_message;
+
        /*
         * IPMI network function and command are encoded in the address
         * within the IPMI OpRegion; see ACPI 4.0, sec 5.5.2.4.3.
         */
        msg->netfn = IPMI_OP_RGN_NETFN(address);
        msg->cmd = IPMI_OP_RGN_CMD(address);
-       msg->data = tx_msg->tx_data;
+       msg->data = tx_msg->data;
+
        /*
         * value is the parameter passed by the IPMI opregion space handler.
         * It points to the IPMI request message buffer
         */
        buffer = (struct acpi_ipmi_buffer *)value;
+
        /* copy the tx message data */
+       if (buffer->length > ACPI_IPMI_MAX_MSG_LENGTH) {
+               dev_WARN_ONCE(tx_msg->device->dev, true,
+                             "Unexpected request (msg len %d).\n",
+                             buffer->length);
+               return -EINVAL;
+       }
        msg->data_len = buffer->length;
-       memcpy(tx_msg->tx_data, buffer->data, msg->data_len);
+       memcpy(tx_msg->data, buffer->data, msg->data_len);
+
        /*
         * now the default type is SYSTEM_INTERFACE and channel type is BMC.
         * If the netfn is APP_REQUEST and the cmd is SEND_MESSAGE,
@@ -179,14 +302,17 @@ static void acpi_format_ipmi_msg(struct acpi_ipmi_msg *tx_msg,
 
        /* Get the msgid */
        device = tx_msg->device;
+
        spin_lock_irqsave(&device->tx_msg_lock, flags);
        device->curr_msgid++;
        tx_msg->tx_msgid = device->curr_msgid;
        spin_unlock_irqrestore(&device->tx_msg_lock, flags);
+
+       return 0;
 }
 
 static void acpi_format_ipmi_response(struct acpi_ipmi_msg *msg,
-               acpi_integer *value, int rem_time)
+                                     acpi_integer *value)
 {
        struct acpi_ipmi_buffer *buffer;
 
@@ -195,110 +321,158 @@ static void acpi_format_ipmi_response(struct acpi_ipmi_msg *msg,
         * IPMI message returned by IPMI command.
         */
        buffer = (struct acpi_ipmi_buffer *)value;
-       if (!rem_time && !msg->msg_done) {
-               buffer->status = ACPI_IPMI_TIMEOUT;
-               return;
-       }
+
        /*
-        * If the flag of msg_done is not set or the recv length is zero, it
-        * means that the IPMI command is not executed correctly.
-        * The status code will be ACPI_IPMI_UNKNOWN.
+        * If the flag of msg_done is not set, it means that the IPMI command is
+        * not executed correctly.
         */
-       if (!msg->msg_done || !msg->rx_len) {
-               buffer->status = ACPI_IPMI_UNKNOWN;
+       buffer->status = msg->msg_done;
+       if (msg->msg_done != ACPI_IPMI_OK)
                return;
-       }
+
        /*
         * If the IPMI response message is obtained correctly, the status code
         * will be ACPI_IPMI_OK
         */
-       buffer->status = ACPI_IPMI_OK;
        buffer->length = msg->rx_len;
-       memcpy(buffer->data, msg->rx_data, msg->rx_len);
+       memcpy(buffer->data, msg->data, msg->rx_len);
 }
 
 static void ipmi_flush_tx_msg(struct acpi_ipmi_device *ipmi)
 {
-       struct acpi_ipmi_msg *tx_msg, *temp;
-       int count = HZ / 10;
-       struct pnp_dev *pnp_dev = ipmi->pnp_dev;
+       struct acpi_ipmi_msg *tx_msg;
+       unsigned long flags;
+
+       /*
+        * NOTE: On-going ipmi_recv_msg
+        * ipmi_msg_handler() may still be invoked by ipmi_si after
+        * flushing.  But it is safe to do a fast flushing on module_exit()
+        * without waiting for all ipmi_recv_msg(s) to complete from
+        * ipmi_msg_handler() as it is ensured by ipmi_si that all
+        * ipmi_recv_msg(s) are freed after invoking ipmi_destroy_user().
+        */
+       spin_lock_irqsave(&ipmi->tx_msg_lock, flags);
+       while (!list_empty(&ipmi->tx_msg_list)) {
+               tx_msg = list_first_entry(&ipmi->tx_msg_list,
+                                         struct acpi_ipmi_msg,
+                                         head);
+               list_del(&tx_msg->head);
+               spin_unlock_irqrestore(&ipmi->tx_msg_lock, flags);
 
-       list_for_each_entry_safe(tx_msg, temp, &ipmi->tx_msg_list, head) {
                /* wake up the sleep thread on the Tx msg */
                complete(&tx_msg->tx_complete);
+               acpi_ipmi_msg_put(tx_msg);
+               spin_lock_irqsave(&ipmi->tx_msg_lock, flags);
        }
+       spin_unlock_irqrestore(&ipmi->tx_msg_lock, flags);
+}
+
+static void ipmi_cancel_tx_msg(struct acpi_ipmi_device *ipmi,
+                              struct acpi_ipmi_msg *msg)
+{
+       struct acpi_ipmi_msg *tx_msg, *temp;
+       bool msg_found = false;
+       unsigned long flags;
 
-       /* wait for about 100ms to flush the tx message list */
-       while (count--) {
-               if (list_empty(&ipmi->tx_msg_list))
+       spin_lock_irqsave(&ipmi->tx_msg_lock, flags);
+       list_for_each_entry_safe(tx_msg, temp, &ipmi->tx_msg_list, head) {
+               if (msg == tx_msg) {
+                       msg_found = true;
+                       list_del(&tx_msg->head);
                        break;
-               schedule_timeout(1);
+               }
        }
-       if (!list_empty(&ipmi->tx_msg_list))
-               dev_warn(&pnp_dev->dev, "tx msg list is not NULL\n");
+       spin_unlock_irqrestore(&ipmi->tx_msg_lock, flags);
+
+       if (msg_found)
+               acpi_ipmi_msg_put(tx_msg);
 }
 
 static void ipmi_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data)
 {
        struct acpi_ipmi_device *ipmi_device = user_msg_data;
-       int msg_found = 0;
-       struct acpi_ipmi_msg *tx_msg;
-       struct pnp_dev *pnp_dev = ipmi_device->pnp_dev;
+       bool msg_found = false;
+       struct acpi_ipmi_msg *tx_msg, *temp;
+       struct device *dev = ipmi_device->dev;
        unsigned long flags;
 
        if (msg->user != ipmi_device->user_interface) {
-               dev_warn(&pnp_dev->dev, "Unexpected response is returned. "
-                       "returned user %p, expected user %p\n",
-                       msg->user, ipmi_device->user_interface);
-               ipmi_free_recv_msg(msg);
-               return;
+               dev_warn(dev,
+                        "Unexpected response is returned. returned user %p, expected user %p\n",
+                        msg->user, ipmi_device->user_interface);
+               goto out_msg;
        }
+
        spin_lock_irqsave(&ipmi_device->tx_msg_lock, flags);
-       list_for_each_entry(tx_msg, &ipmi_device->tx_msg_list, head) {
+       list_for_each_entry_safe(tx_msg, temp, &ipmi_device->tx_msg_list, head) {
                if (msg->msgid == tx_msg->tx_msgid) {
-                       msg_found = 1;
+                       msg_found = true;
+                       list_del(&tx_msg->head);
                        break;
                }
        }
-
        spin_unlock_irqrestore(&ipmi_device->tx_msg_lock, flags);
+
        if (!msg_found) {
-               dev_warn(&pnp_dev->dev, "Unexpected response (msg id %ld) is "
-                       "returned.\n", msg->msgid);
-               ipmi_free_recv_msg(msg);
-               return;
+               dev_warn(dev,
+                        "Unexpected response (msg id %ld) is returned.\n",
+                        msg->msgid);
+               goto out_msg;
        }
 
-       if (msg->msg.data_len) {
-               /* copy the response data to Rx_data buffer */
-               memcpy(tx_msg->rx_data, msg->msg_data, msg->msg.data_len);
-               tx_msg->rx_len = msg->msg.data_len;
-               tx_msg->msg_done = 1;
+       /* copy the response data to Rx_data buffer */
+       if (msg->msg.data_len > ACPI_IPMI_MAX_MSG_LENGTH) {
+               dev_WARN_ONCE(dev, true,
+                             "Unexpected response (msg len %d).\n",
+                             msg->msg.data_len);
+               goto out_comp;
        }
+
+       /* response msg is an error msg */
+       msg->recv_type = IPMI_RESPONSE_RECV_TYPE;
+       if (msg->recv_type == IPMI_RESPONSE_RECV_TYPE &&
+           msg->msg.data_len == 1) {
+               if (msg->msg.data[0] == IPMI_TIMEOUT_COMPLETION_CODE) {
+                       dev_WARN_ONCE(dev, true,
+                                     "Unexpected response (timeout).\n");
+                       tx_msg->msg_done = ACPI_IPMI_TIMEOUT;
+               }
+               goto out_comp;
+       }
+
+       tx_msg->rx_len = msg->msg.data_len;
+       memcpy(tx_msg->data, msg->msg.data, tx_msg->rx_len);
+       tx_msg->msg_done = ACPI_IPMI_OK;
+
+out_comp:
        complete(&tx_msg->tx_complete);
+       acpi_ipmi_msg_put(tx_msg);
+out_msg:
        ipmi_free_recv_msg(msg);
-};
+}
 
 static void ipmi_register_bmc(int iface, struct device *dev)
 {
        struct acpi_ipmi_device *ipmi_device, *temp;
-       struct pnp_dev *pnp_dev;
-       ipmi_user_t             user;
        int err;
        struct ipmi_smi_info smi_data;
        acpi_handle handle;
 
        err = ipmi_get_smi_info(iface, &smi_data);
-
        if (err)
                return;
 
-       if (smi_data.addr_src != SI_ACPI) {
-               put_device(smi_data.dev);
-               return;
-       }
-
+       if (smi_data.addr_src != SI_ACPI)
+               goto err_ref;
        handle = smi_data.addr_info.acpi_info.acpi_handle;
+       if (!handle)
+               goto err_ref;
+
+       ipmi_device = ipmi_dev_alloc(iface, smi_data.dev, handle);
+       if (!ipmi_device) {
+               dev_warn(smi_data.dev, "Can't create IPMI user interface\n");
+               goto err_ref;
+       }
 
        mutex_lock(&driver_data.ipmi_lock);
        list_for_each_entry(temp, &driver_data.ipmi_devices, head) {
@@ -307,34 +481,20 @@ static void ipmi_register_bmc(int iface, struct device *dev)
                 * to the device list, don't add it again.
                 */
                if (temp->handle == handle)
-                       goto out;
+                       goto err_lock;
        }
-
-       ipmi_device = kzalloc(sizeof(*ipmi_device), GFP_KERNEL);
-
-       if (!ipmi_device)
-               goto out;
-
-       pnp_dev = to_pnp_dev(smi_data.dev);
-       ipmi_device->handle = handle;
-       ipmi_device->pnp_dev = pnp_dev;
-
-       err = ipmi_create_user(iface, &driver_data.ipmi_hndlrs,
-                                       ipmi_device, &user);
-       if (err) {
-               dev_warn(&pnp_dev->dev, "Can't create IPMI user interface\n");
-               kfree(ipmi_device);
-               goto out;
-       }
-       acpi_add_ipmi_device(ipmi_device);
-       ipmi_device->user_interface = user;
-       ipmi_device->ipmi_ifnum = iface;
+       if (!driver_data.selected_smi)
+               driver_data.selected_smi = ipmi_device;
+       list_add_tail(&ipmi_device->head, &driver_data.ipmi_devices);
        mutex_unlock(&driver_data.ipmi_lock);
-       memcpy(&ipmi_device->smi_data, &smi_data, sizeof(struct ipmi_smi_info));
+
+       put_device(smi_data.dev);
        return;
 
-out:
+err_lock:
        mutex_unlock(&driver_data.ipmi_lock);
+       ipmi_dev_release(ipmi_device);
+err_ref:
        put_device(smi_data.dev);
        return;
 }
@@ -342,23 +502,29 @@ out:
 static void ipmi_bmc_gone(int iface)
 {
        struct acpi_ipmi_device *ipmi_device, *temp;
+       bool dev_found = false;
 
        mutex_lock(&driver_data.ipmi_lock);
        list_for_each_entry_safe(ipmi_device, temp,
-                               &driver_data.ipmi_devices, head) {
-               if (ipmi_device->ipmi_ifnum != iface)
-                       continue;
-
-               acpi_remove_ipmi_device(ipmi_device);
-               put_device(ipmi_device->smi_data.dev);
-               kfree(ipmi_device);
-               break;
+                                &driver_data.ipmi_devices, head) {
+               if (ipmi_device->ipmi_ifnum != iface) {
+                       dev_found = true;
+                       __ipmi_dev_kill(ipmi_device);
+                       break;
+               }
        }
+       if (!driver_data.selected_smi)
+               driver_data.selected_smi = list_first_entry_or_null(
+                                       &driver_data.ipmi_devices,
+                                       struct acpi_ipmi_device, head);
        mutex_unlock(&driver_data.ipmi_lock);
+
+       if (dev_found) {
+               ipmi_flush_tx_msg(ipmi_device);
+               acpi_ipmi_dev_put(ipmi_device);
+       }
 }
-/* --------------------------------------------------------------------------
- *                     Address Space Management
- * -------------------------------------------------------------------------- */
+
 /*
  * This is the IPMI opregion space handler.
  * @function: indicates the read/write. In fact as the IPMI message is driven
@@ -371,17 +537,17 @@ static void ipmi_bmc_gone(int iface)
  *          the response IPMI message returned by IPMI command.
  * @handler_context: IPMI device context.
  */
-
 static acpi_status
 acpi_ipmi_space_handler(u32 function, acpi_physical_address address,
-                     u32 bits, acpi_integer *value,
-                     void *handler_context, void *region_context)
+                       u32 bits, acpi_integer *value,
+                       void *handler_context, void *region_context)
 {
        struct acpi_ipmi_msg *tx_msg;
-       struct acpi_ipmi_device *ipmi_device = handler_context;
-       int err, rem_time;
+       struct acpi_ipmi_device *ipmi_device;
+       int err;
        acpi_status status;
        unsigned long flags;
+
        /*
         * IPMI opregion message.
         * IPMI message is firstly written to the BMC and system software
@@ -391,118 +557,75 @@ acpi_ipmi_space_handler(u32 function, acpi_physical_address address,
        if ((function & ACPI_IO_MASK) == ACPI_READ)
                return AE_TYPE;
 
-       if (!ipmi_device->user_interface)
+       tx_msg = ipmi_msg_alloc();
+       if (!tx_msg)
                return AE_NOT_EXIST;
+       ipmi_device = tx_msg->device;
 
-       tx_msg = acpi_alloc_ipmi_msg(ipmi_device);
-       if (!tx_msg)
-               return AE_NO_MEMORY;
+       if (acpi_format_ipmi_request(tx_msg, address, value) != 0) {
+               ipmi_msg_release(tx_msg);
+               return AE_TYPE;
+       }
 
-       acpi_format_ipmi_msg(tx_msg, address, value);
+       acpi_ipmi_msg_get(tx_msg);
+       mutex_lock(&driver_data.ipmi_lock);
+       /* Do not add a tx_msg that can not be flushed. */
+       if (ipmi_device->dead) {
+               mutex_unlock(&driver_data.ipmi_lock);
+               ipmi_msg_release(tx_msg);
+               return AE_NOT_EXIST;
+       }
        spin_lock_irqsave(&ipmi_device->tx_msg_lock, flags);
        list_add_tail(&tx_msg->head, &ipmi_device->tx_msg_list);
        spin_unlock_irqrestore(&ipmi_device->tx_msg_lock, flags);
+       mutex_unlock(&driver_data.ipmi_lock);
+
        err = ipmi_request_settime(ipmi_device->user_interface,
-                                       &tx_msg->addr,
-                                       tx_msg->tx_msgid,
-                                       &tx_msg->tx_message,
-                                       NULL, 0, 0, 0);
+                                  &tx_msg->addr,
+                                  tx_msg->tx_msgid,
+                                  &tx_msg->tx_message,
+                                  NULL, 0, 0, IPMI_TIMEOUT);
        if (err) {
                status = AE_ERROR;
-               goto end_label;
+               goto out_msg;
        }
-       rem_time = wait_for_completion_timeout(&tx_msg->tx_complete,
-                                       IPMI_TIMEOUT);
-       acpi_format_ipmi_response(tx_msg, value, rem_time);
+       wait_for_completion(&tx_msg->tx_complete);
+
+       acpi_format_ipmi_response(tx_msg, value);
        status = AE_OK;
 
-end_label:
-       spin_lock_irqsave(&ipmi_device->tx_msg_lock, flags);
-       list_del(&tx_msg->head);
-       spin_unlock_irqrestore(&ipmi_device->tx_msg_lock, flags);
-       kfree(tx_msg);
+out_msg:
+       ipmi_cancel_tx_msg(ipmi_device, tx_msg);
+       acpi_ipmi_msg_put(tx_msg);
        return status;
 }
 
-static void ipmi_remove_space_handler(struct acpi_ipmi_device *ipmi)
-{
-       if (!test_bit(IPMI_FLAGS_HANDLER_INSTALL, &ipmi->flags))
-               return;
-
-       acpi_remove_address_space_handler(ipmi->handle,
-                               ACPI_ADR_SPACE_IPMI, &acpi_ipmi_space_handler);
-
-       clear_bit(IPMI_FLAGS_HANDLER_INSTALL, &ipmi->flags);
-}
-
-static int ipmi_install_space_handler(struct acpi_ipmi_device *ipmi)
+static int __init acpi_ipmi_init(void)
 {
+       int result;
        acpi_status status;
 
-       if (test_bit(IPMI_FLAGS_HANDLER_INSTALL, &ipmi->flags))
+       if (acpi_disabled)
                return 0;
 
-       status = acpi_install_address_space_handler(ipmi->handle,
+       status = acpi_install_address_space_handler(ACPI_ROOT_OBJECT,
                                                    ACPI_ADR_SPACE_IPMI,
                                                    &acpi_ipmi_space_handler,
-                                                   NULL, ipmi);
+                                                   NULL, NULL);
        if (ACPI_FAILURE(status)) {
-               struct pnp_dev *pnp_dev = ipmi->pnp_dev;
-               dev_warn(&pnp_dev->dev, "Can't register IPMI opregion space "
-                       "handle\n");
+               pr_warn("Can't register IPMI opregion space handle\n");
                return -EINVAL;
        }
-       set_bit(IPMI_FLAGS_HANDLER_INSTALL, &ipmi->flags);
-       return 0;
-}
-
-static void acpi_add_ipmi_device(struct acpi_ipmi_device *ipmi_device)
-{
-
-       INIT_LIST_HEAD(&ipmi_device->head);
-
-       spin_lock_init(&ipmi_device->tx_msg_lock);
-       INIT_LIST_HEAD(&ipmi_device->tx_msg_list);
-       ipmi_install_space_handler(ipmi_device);
-
-       list_add_tail(&ipmi_device->head, &driver_data.ipmi_devices);
-}
-
-static void acpi_remove_ipmi_device(struct acpi_ipmi_device *ipmi_device)
-{
-       /*
-        * If the IPMI user interface is created, it should be
-        * destroyed.
-        */
-       if (ipmi_device->user_interface) {
-               ipmi_destroy_user(ipmi_device->user_interface);
-               ipmi_device->user_interface = NULL;
-       }
-       /* flush the Tx_msg list */
-       if (!list_empty(&ipmi_device->tx_msg_list))
-               ipmi_flush_tx_msg(ipmi_device);
-
-       list_del(&ipmi_device->head);
-       ipmi_remove_space_handler(ipmi_device);
-}
-
-static int __init acpi_ipmi_init(void)
-{
-       int result = 0;
-
-       if (acpi_disabled)
-               return result;
-
-       mutex_init(&driver_data.ipmi_lock);
-
        result = ipmi_smi_watcher_register(&driver_data.bmc_events);
+       if (result)
+               pr_err("Can't register IPMI system interface watcher\n");
 
        return result;
 }
 
 static void __exit acpi_ipmi_exit(void)
 {
-       struct acpi_ipmi_device *ipmi_device, *temp;
+       struct acpi_ipmi_device *ipmi_device;
 
        if (acpi_disabled)
                return;
@@ -516,13 +639,22 @@ static void __exit acpi_ipmi_exit(void)
         * handler and free it.
         */
        mutex_lock(&driver_data.ipmi_lock);
-       list_for_each_entry_safe(ipmi_device, temp,
-                               &driver_data.ipmi_devices, head) {
-               acpi_remove_ipmi_device(ipmi_device);
-               put_device(ipmi_device->smi_data.dev);
-               kfree(ipmi_device);
+       while (!list_empty(&driver_data.ipmi_devices)) {
+               ipmi_device = list_first_entry(&driver_data.ipmi_devices,
+                                              struct acpi_ipmi_device,
+                                              head);
+               __ipmi_dev_kill(ipmi_device);
+               mutex_unlock(&driver_data.ipmi_lock);
+
+               ipmi_flush_tx_msg(ipmi_device);
+               acpi_ipmi_dev_put(ipmi_device);
+
+               mutex_lock(&driver_data.ipmi_lock);
        }
        mutex_unlock(&driver_data.ipmi_lock);
+       acpi_remove_address_space_handler(ACPI_ROOT_OBJECT,
+                                         ACPI_ADR_SPACE_IPMI,
+                                         &acpi_ipmi_space_handler);
 }
 
 module_init(acpi_ipmi_init);