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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/char/ipmi/ipmi_ssif.c
Initial import
Diffstat (limited to 'drivers/char/ipmi/ipmi_ssif.c')
-rw-r--r--drivers/char/ipmi/ipmi_ssif.c2017
1 files changed, 2017 insertions, 0 deletions
diff --git a/drivers/char/ipmi/ipmi_ssif.c b/drivers/char/ipmi/ipmi_ssif.c
new file mode 100644
index 000000000..207689c44
--- /dev/null
+++ b/drivers/char/ipmi/ipmi_ssif.c
@@ -0,0 +1,2017 @@
+/*
+ * ipmi_ssif.c
+ *
+ * The interface to the IPMI driver for SMBus access to a SMBus
+ * compliant device. Called SSIF by the IPMI spec.
+ *
+ * Author: Intel Corporation
+ * Todd Davis <todd.c.davis@intel.com>
+ *
+ * Rewritten by Corey Minyard <minyard@acm.org> to support the
+ * non-blocking I2C interface, add support for multi-part
+ * transactions, add PEC support, and general clenaup.
+ *
+ * Copyright 2003 Intel Corporation
+ * Copyright 2005 MontaVista Software
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ */
+
+/*
+ * This file holds the "policy" for the interface to the SSIF state
+ * machine. It does the configuration, handles timers and interrupts,
+ * and drives the real SSIF state machine.
+ */
+
+/*
+ * TODO: Figure out how to use SMB alerts. This will require a new
+ * interface into the I2C driver, I believe.
+ */
+
+#if defined(MODVERSIONS)
+#include <linux/modversions.h>
+#endif
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/sched.h>
+#include <linux/seq_file.h>
+#include <linux/timer.h>
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/spinlock.h>
+#include <linux/slab.h>
+#include <linux/list.h>
+#include <linux/i2c.h>
+#include <linux/ipmi_smi.h>
+#include <linux/init.h>
+#include <linux/dmi.h>
+#include <linux/kthread.h>
+#include <linux/acpi.h>
+#include <linux/ctype.h>
+
+#define PFX "ipmi_ssif: "
+#define DEVICE_NAME "ipmi_ssif"
+
+#define IPMI_GET_SYSTEM_INTERFACE_CAPABILITIES_CMD 0x57
+
+#define SSIF_IPMI_REQUEST 2
+#define SSIF_IPMI_MULTI_PART_REQUEST_START 6
+#define SSIF_IPMI_MULTI_PART_REQUEST_MIDDLE 7
+#define SSIF_IPMI_RESPONSE 3
+#define SSIF_IPMI_MULTI_PART_RESPONSE_MIDDLE 9
+
+/* ssif_debug is a bit-field
+ * SSIF_DEBUG_MSG - commands and their responses
+ * SSIF_DEBUG_STATES - message states
+ * SSIF_DEBUG_TIMING - Measure times between events in the driver
+ */
+#define SSIF_DEBUG_TIMING 4
+#define SSIF_DEBUG_STATE 2
+#define SSIF_DEBUG_MSG 1
+#define SSIF_NODEBUG 0
+#define SSIF_DEFAULT_DEBUG (SSIF_NODEBUG)
+
+/*
+ * Timer values
+ */
+#define SSIF_MSG_USEC 20000 /* 20ms between message tries. */
+#define SSIF_MSG_PART_USEC 5000 /* 5ms for a message part */
+
+/* How many times to we retry sending/receiving the message. */
+#define SSIF_SEND_RETRIES 5
+#define SSIF_RECV_RETRIES 250
+
+#define SSIF_MSG_MSEC (SSIF_MSG_USEC / 1000)
+#define SSIF_MSG_JIFFIES ((SSIF_MSG_USEC * 1000) / TICK_NSEC)
+#define SSIF_MSG_PART_JIFFIES ((SSIF_MSG_PART_USEC * 1000) / TICK_NSEC)
+
+enum ssif_intf_state {
+ SSIF_NORMAL,
+ SSIF_GETTING_FLAGS,
+ SSIF_GETTING_EVENTS,
+ SSIF_CLEARING_FLAGS,
+ SSIF_GETTING_MESSAGES,
+ /* FIXME - add watchdog stuff. */
+};
+
+#define SSIF_IDLE(ssif) ((ssif)->ssif_state == SSIF_NORMAL \
+ && (ssif)->curr_msg == NULL)
+
+/*
+ * Indexes into stats[] in ssif_info below.
+ */
+enum ssif_stat_indexes {
+ /* Number of total messages sent. */
+ SSIF_STAT_sent_messages = 0,
+
+ /*
+ * Number of message parts sent. Messages may be broken into
+ * parts if they are long.
+ */
+ SSIF_STAT_sent_messages_parts,
+
+ /*
+ * Number of time a message was retried.
+ */
+ SSIF_STAT_send_retries,
+
+ /*
+ * Number of times the send of a message failed.
+ */
+ SSIF_STAT_send_errors,
+
+ /*
+ * Number of message responses received.
+ */
+ SSIF_STAT_received_messages,
+
+ /*
+ * Number of message fragments received.
+ */
+ SSIF_STAT_received_message_parts,
+
+ /*
+ * Number of times the receive of a message was retried.
+ */
+ SSIF_STAT_receive_retries,
+
+ /*
+ * Number of errors receiving messages.
+ */
+ SSIF_STAT_receive_errors,
+
+ /*
+ * Number of times a flag fetch was requested.
+ */
+ SSIF_STAT_flag_fetches,
+
+ /*
+ * Number of times the hardware didn't follow the state machine.
+ */
+ SSIF_STAT_hosed,
+
+ /*
+ * Number of received events.
+ */
+ SSIF_STAT_events,
+
+ /* Number of asyncronous messages received. */
+ SSIF_STAT_incoming_messages,
+
+ /* Number of watchdog pretimeouts. */
+ SSIF_STAT_watchdog_pretimeouts,
+
+ /* Number of alers received. */
+ SSIF_STAT_alerts,
+
+ /* Always add statistics before this value, it must be last. */
+ SSIF_NUM_STATS
+};
+
+struct ssif_addr_info {
+ unsigned short addr;
+ struct i2c_board_info binfo;
+ char *adapter_name;
+ int debug;
+ int slave_addr;
+ enum ipmi_addr_src addr_src;
+ union ipmi_smi_info_union addr_info;
+
+ struct mutex clients_mutex;
+ struct list_head clients;
+
+ struct list_head link;
+};
+
+struct ssif_info;
+
+typedef void (*ssif_i2c_done)(struct ssif_info *ssif_info, int result,
+ unsigned char *data, unsigned int len);
+
+struct ssif_info {
+ ipmi_smi_t intf;
+ int intf_num;
+ spinlock_t lock;
+ struct ipmi_smi_msg *waiting_msg;
+ struct ipmi_smi_msg *curr_msg;
+ enum ssif_intf_state ssif_state;
+ unsigned long ssif_debug;
+
+ struct ipmi_smi_handlers handlers;
+
+ enum ipmi_addr_src addr_source; /* ACPI, PCI, SMBIOS, hardcode, etc. */
+ union ipmi_smi_info_union addr_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
+ unsigned char msg_flags;
+
+ u8 global_enables;
+ bool has_event_buffer;
+ bool supports_alert;
+
+ /*
+ * Used to tell what we should do with alerts. If we are
+ * waiting on a response, read the data immediately.
+ */
+ bool got_alert;
+ bool waiting_alert;
+
+ /*
+ * If set to true, this will request events the next time the
+ * state machine is idle.
+ */
+ bool req_events;
+
+ /*
+ * If set to true, this will request flags the next time the
+ * state machine is idle.
+ */
+ bool req_flags;
+
+ /*
+ * Used to perform timer operations when run-to-completion
+ * mode is on. This is a countdown timer.
+ */
+ int rtc_us_timer;
+
+ /* Used for sending/receiving data. +1 for the length. */
+ unsigned char data[IPMI_MAX_MSG_LENGTH + 1];
+ unsigned int data_len;
+
+ /* Temp receive buffer, gets copied into data. */
+ unsigned char recv[I2C_SMBUS_BLOCK_MAX];
+
+ struct i2c_client *client;
+ ssif_i2c_done done_handler;
+
+ /* Thread interface handling */
+ struct task_struct *thread;
+ struct completion wake_thread;
+ bool stopping;
+ int i2c_read_write;
+ int i2c_command;
+ unsigned char *i2c_data;
+ unsigned int i2c_size;
+
+ /* From the device id response. */
+ struct ipmi_device_id device_id;
+
+ struct timer_list retry_timer;
+ int retries_left;
+
+ /* Info from SSIF cmd */
+ unsigned char max_xmit_msg_size;
+ unsigned char max_recv_msg_size;
+ unsigned int multi_support;
+ int supports_pec;
+
+#define SSIF_NO_MULTI 0
+#define SSIF_MULTI_2_PART 1
+#define SSIF_MULTI_n_PART 2
+ unsigned char *multi_data;
+ unsigned int multi_len;
+ unsigned int multi_pos;
+
+ atomic_t stats[SSIF_NUM_STATS];
+};
+
+#define ssif_inc_stat(ssif, stat) \
+ atomic_inc(&(ssif)->stats[SSIF_STAT_ ## stat])
+#define ssif_get_stat(ssif, stat) \
+ ((unsigned int) atomic_read(&(ssif)->stats[SSIF_STAT_ ## stat]))
+
+static bool initialized;
+
+static atomic_t next_intf = ATOMIC_INIT(0);
+
+static void return_hosed_msg(struct ssif_info *ssif_info,
+ struct ipmi_smi_msg *msg);
+static void start_next_msg(struct ssif_info *ssif_info, unsigned long *flags);
+static int start_send(struct ssif_info *ssif_info,
+ unsigned char *data,
+ unsigned int len);
+
+static unsigned long *ipmi_ssif_lock_cond(struct ssif_info *ssif_info,
+ unsigned long *flags)
+{
+ spin_lock_irqsave(&ssif_info->lock, *flags);
+ return flags;
+}
+
+static void ipmi_ssif_unlock_cond(struct ssif_info *ssif_info,
+ unsigned long *flags)
+{
+ spin_unlock_irqrestore(&ssif_info->lock, *flags);
+}
+
+static void deliver_recv_msg(struct ssif_info *ssif_info,
+ struct ipmi_smi_msg *msg)
+{
+ ipmi_smi_t intf = ssif_info->intf;
+
+ if (!intf) {
+ ipmi_free_smi_msg(msg);
+ } else if (msg->rsp_size < 0) {
+ return_hosed_msg(ssif_info, msg);
+ pr_err(PFX
+ "Malformed message in deliver_recv_msg: rsp_size = %d\n",
+ msg->rsp_size);
+ } else {
+ ipmi_smi_msg_received(intf, msg);
+ }
+}
+
+static void return_hosed_msg(struct ssif_info *ssif_info,
+ struct ipmi_smi_msg *msg)
+{
+ ssif_inc_stat(ssif_info, hosed);
+
+ /* Make it a response */
+ msg->rsp[0] = msg->data[0] | 4;
+ msg->rsp[1] = msg->data[1];
+ msg->rsp[2] = 0xFF; /* Unknown error. */
+ msg->rsp_size = 3;
+
+ deliver_recv_msg(ssif_info, msg);
+}
+
+/*
+ * Must be called with the message lock held. This will release the
+ * message lock. Note that the caller will check SSIF_IDLE and start a
+ * new operation, so there is no need to check for new messages to
+ * start in here.
+ */
+static void start_clear_flags(struct ssif_info *ssif_info, unsigned long *flags)
+{
+ unsigned char msg[3];
+
+ ssif_info->msg_flags &= ~WDT_PRE_TIMEOUT_INT;
+ ssif_info->ssif_state = SSIF_CLEARING_FLAGS;
+ ipmi_ssif_unlock_cond(ssif_info, flags);
+
+ /* 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;
+
+ if (start_send(ssif_info, msg, 3) != 0) {
+ /* Error, just go to normal state. */
+ ssif_info->ssif_state = SSIF_NORMAL;
+ }
+}
+
+static void start_flag_fetch(struct ssif_info *ssif_info, unsigned long *flags)
+{
+ unsigned char mb[2];
+
+ ssif_info->req_flags = false;
+ ssif_info->ssif_state = SSIF_GETTING_FLAGS;
+ ipmi_ssif_unlock_cond(ssif_info, flags);
+
+ mb[0] = (IPMI_NETFN_APP_REQUEST << 2);
+ mb[1] = IPMI_GET_MSG_FLAGS_CMD;
+ if (start_send(ssif_info, mb, 2) != 0)
+ ssif_info->ssif_state = SSIF_NORMAL;
+}
+
+static void check_start_send(struct ssif_info *ssif_info, unsigned long *flags,
+ struct ipmi_smi_msg *msg)
+{
+ if (start_send(ssif_info, msg->data, msg->data_size) != 0) {
+ unsigned long oflags;
+
+ flags = ipmi_ssif_lock_cond(ssif_info, &oflags);
+ ssif_info->curr_msg = NULL;
+ ssif_info->ssif_state = SSIF_NORMAL;
+ ipmi_ssif_unlock_cond(ssif_info, flags);
+ ipmi_free_smi_msg(msg);
+ }
+}
+
+static void start_event_fetch(struct ssif_info *ssif_info, unsigned long *flags)
+{
+ struct ipmi_smi_msg *msg;
+
+ ssif_info->req_events = false;
+
+ msg = ipmi_alloc_smi_msg();
+ if (!msg) {
+ ssif_info->ssif_state = SSIF_NORMAL;
+ return;
+ }
+
+ ssif_info->curr_msg = msg;
+ ssif_info->ssif_state = SSIF_GETTING_EVENTS;
+ ipmi_ssif_unlock_cond(ssif_info, flags);
+
+ msg->data[0] = (IPMI_NETFN_APP_REQUEST << 2);
+ msg->data[1] = IPMI_READ_EVENT_MSG_BUFFER_CMD;
+ msg->data_size = 2;
+
+ check_start_send(ssif_info, flags, msg);
+}
+
+static void start_recv_msg_fetch(struct ssif_info *ssif_info,
+ unsigned long *flags)
+{
+ struct ipmi_smi_msg *msg;
+
+ msg = ipmi_alloc_smi_msg();
+ if (!msg) {
+ ssif_info->ssif_state = SSIF_NORMAL;
+ return;
+ }
+
+ ssif_info->curr_msg = msg;
+ ssif_info->ssif_state = SSIF_GETTING_MESSAGES;
+ ipmi_ssif_unlock_cond(ssif_info, flags);
+
+ msg->data[0] = (IPMI_NETFN_APP_REQUEST << 2);
+ msg->data[1] = IPMI_GET_MSG_CMD;
+ msg->data_size = 2;
+
+ check_start_send(ssif_info, flags, msg);
+}
+
+/*
+ * Must be called with the message lock held. This will release the
+ * message lock. Note that the caller will check SSIF_IDLE and start a
+ * new operation, so there is no need to check for new messages to
+ * start in here.
+ */
+static void handle_flags(struct ssif_info *ssif_info, unsigned long *flags)
+{
+ if (ssif_info->msg_flags & WDT_PRE_TIMEOUT_INT) {
+ ipmi_smi_t intf = ssif_info->intf;
+ /* Watchdog pre-timeout */
+ ssif_inc_stat(ssif_info, watchdog_pretimeouts);
+ start_clear_flags(ssif_info, flags);
+ if (intf)
+ ipmi_smi_watchdog_pretimeout(intf);
+ } else if (ssif_info->msg_flags & RECEIVE_MSG_AVAIL)
+ /* Messages available. */
+ start_recv_msg_fetch(ssif_info, flags);
+ else if (ssif_info->msg_flags & EVENT_MSG_BUFFER_FULL)
+ /* Events available. */
+ start_event_fetch(ssif_info, flags);
+ else {
+ ssif_info->ssif_state = SSIF_NORMAL;
+ ipmi_ssif_unlock_cond(ssif_info, flags);
+ }
+}
+
+static int ipmi_ssif_thread(void *data)
+{
+ struct ssif_info *ssif_info = data;
+
+ while (!kthread_should_stop()) {
+ int result;
+
+ /* Wait for something to do */
+ result = wait_for_completion_interruptible(
+ &ssif_info->wake_thread);
+ if (ssif_info->stopping)
+ break;
+ if (result == -ERESTARTSYS)
+ continue;
+ init_completion(&ssif_info->wake_thread);
+
+ if (ssif_info->i2c_read_write == I2C_SMBUS_WRITE) {
+ result = i2c_smbus_write_block_data(
+ ssif_info->client, ssif_info->i2c_command,
+ ssif_info->i2c_data[0],
+ ssif_info->i2c_data + 1);
+ ssif_info->done_handler(ssif_info, result, NULL, 0);
+ } else {
+ result = i2c_smbus_read_block_data(
+ ssif_info->client, ssif_info->i2c_command,
+ ssif_info->i2c_data);
+ if (result < 0)
+ ssif_info->done_handler(ssif_info, result,
+ NULL, 0);
+ else
+ ssif_info->done_handler(ssif_info, 0,
+ ssif_info->i2c_data,
+ result);
+ }
+ }
+
+ return 0;
+}
+
+static int ssif_i2c_send(struct ssif_info *ssif_info,
+ ssif_i2c_done handler,
+ int read_write, int command,
+ unsigned char *data, unsigned int size)
+{
+ ssif_info->done_handler = handler;
+
+ ssif_info->i2c_read_write = read_write;
+ ssif_info->i2c_command = command;
+ ssif_info->i2c_data = data;
+ ssif_info->i2c_size = size;
+ complete(&ssif_info->wake_thread);
+ return 0;
+}
+
+
+static void msg_done_handler(struct ssif_info *ssif_info, int result,
+ unsigned char *data, unsigned int len);
+
+static void start_get(struct ssif_info *ssif_info)
+{
+ int rv;
+
+ ssif_info->rtc_us_timer = 0;
+ ssif_info->multi_pos = 0;
+
+ rv = ssif_i2c_send(ssif_info, msg_done_handler, I2C_SMBUS_READ,
+ SSIF_IPMI_RESPONSE,
+ ssif_info->recv, I2C_SMBUS_BLOCK_DATA);
+ if (rv < 0) {
+ /* request failed, just return the error. */
+ if (ssif_info->ssif_debug & SSIF_DEBUG_MSG)
+ pr_info("Error from i2c_non_blocking_op(5)\n");
+
+ msg_done_handler(ssif_info, -EIO, NULL, 0);
+ }
+}
+
+static void retry_timeout(unsigned long data)
+{
+ struct ssif_info *ssif_info = (void *) data;
+ unsigned long oflags, *flags;
+ bool waiting;
+
+ if (ssif_info->stopping)
+ return;
+
+ flags = ipmi_ssif_lock_cond(ssif_info, &oflags);
+ waiting = ssif_info->waiting_alert;
+ ssif_info->waiting_alert = false;
+ ipmi_ssif_unlock_cond(ssif_info, flags);
+
+ if (waiting)
+ start_get(ssif_info);
+}
+
+
+static void ssif_alert(struct i2c_client *client, unsigned int data)
+{
+ struct ssif_info *ssif_info = i2c_get_clientdata(client);
+ unsigned long oflags, *flags;
+ bool do_get = false;
+
+ ssif_inc_stat(ssif_info, alerts);
+
+ flags = ipmi_ssif_lock_cond(ssif_info, &oflags);
+ if (ssif_info->waiting_alert) {
+ ssif_info->waiting_alert = false;
+ del_timer(&ssif_info->retry_timer);
+ do_get = true;
+ } else if (ssif_info->curr_msg) {
+ ssif_info->got_alert = true;
+ }
+ ipmi_ssif_unlock_cond(ssif_info, flags);
+ if (do_get)
+ start_get(ssif_info);
+}
+
+static int start_resend(struct ssif_info *ssif_info);
+
+static void msg_done_handler(struct ssif_info *ssif_info, int result,
+ unsigned char *data, unsigned int len)
+{
+ struct ipmi_smi_msg *msg;
+ unsigned long oflags, *flags;
+ int rv;
+
+ /*
+ * We are single-threaded here, so no need for a lock until we
+ * start messing with driver states or the queues.
+ */
+
+ if (result < 0) {
+ ssif_info->retries_left--;
+ if (ssif_info->retries_left > 0) {
+ ssif_inc_stat(ssif_info, receive_retries);
+
+ flags = ipmi_ssif_lock_cond(ssif_info, &oflags);
+ ssif_info->waiting_alert = true;
+ ssif_info->rtc_us_timer = SSIF_MSG_USEC;
+ mod_timer(&ssif_info->retry_timer,
+ jiffies + SSIF_MSG_JIFFIES);
+ ipmi_ssif_unlock_cond(ssif_info, flags);
+ return;
+ }
+
+ ssif_inc_stat(ssif_info, receive_errors);
+
+ if (ssif_info->ssif_debug & SSIF_DEBUG_MSG)
+ pr_info("Error in msg_done_handler: %d\n", result);
+ len = 0;
+ goto continue_op;
+ }
+
+ if ((len > 1) && (ssif_info->multi_pos == 0)
+ && (data[0] == 0x00) && (data[1] == 0x01)) {
+ /* Start of multi-part read. Start the next transaction. */
+ int i;
+
+ ssif_inc_stat(ssif_info, received_message_parts);
+
+ /* Remove the multi-part read marker. */
+ len -= 2;
+ for (i = 0; i < len; i++)
+ ssif_info->data[i] = data[i+2];
+ ssif_info->multi_len = len;
+ ssif_info->multi_pos = 1;
+
+ rv = ssif_i2c_send(ssif_info, msg_done_handler, I2C_SMBUS_READ,
+ SSIF_IPMI_MULTI_PART_RESPONSE_MIDDLE,
+ ssif_info->recv, I2C_SMBUS_BLOCK_DATA);
+ if (rv < 0) {
+ if (ssif_info->ssif_debug & SSIF_DEBUG_MSG)
+ pr_info("Error from i2c_non_blocking_op(1)\n");
+
+ result = -EIO;
+ } else
+ return;
+ } else if (ssif_info->multi_pos) {
+ /* Middle of multi-part read. Start the next transaction. */
+ int i;
+ unsigned char blocknum;
+
+ if (len == 0) {
+ result = -EIO;
+ if (ssif_info->ssif_debug & SSIF_DEBUG_MSG)
+ pr_info(PFX "Middle message with no data\n");
+
+ goto continue_op;
+ }
+
+ blocknum = data[0];
+
+ if (ssif_info->multi_len + len - 1 > IPMI_MAX_MSG_LENGTH) {
+ /* Received message too big, abort the operation. */
+ result = -E2BIG;
+ if (ssif_info->ssif_debug & SSIF_DEBUG_MSG)
+ pr_info("Received message too big\n");
+
+ goto continue_op;
+ }
+
+ /* Remove the blocknum from the data. */
+ len--;
+ for (i = 0; i < len; i++)
+ ssif_info->data[i + ssif_info->multi_len] = data[i + 1];
+ ssif_info->multi_len += len;
+ if (blocknum == 0xff) {
+ /* End of read */
+ len = ssif_info->multi_len;
+ data = ssif_info->data;
+ } else if (blocknum + 1 != ssif_info->multi_pos) {
+ /*
+ * Out of sequence block, just abort. Block
+ * numbers start at zero for the second block,
+ * but multi_pos starts at one, so the +1.
+ */
+ result = -EIO;
+ } else {
+ ssif_inc_stat(ssif_info, received_message_parts);
+
+ ssif_info->multi_pos++;
+
+ rv = ssif_i2c_send(ssif_info, msg_done_handler,
+ I2C_SMBUS_READ,
+ SSIF_IPMI_MULTI_PART_RESPONSE_MIDDLE,
+ ssif_info->recv,
+ I2C_SMBUS_BLOCK_DATA);
+ if (rv < 0) {
+ if (ssif_info->ssif_debug & SSIF_DEBUG_MSG)
+ pr_info(PFX
+ "Error from ssif_i2c_send\n");
+
+ result = -EIO;
+ } else
+ return;
+ }
+ }
+
+ if (result < 0) {
+ ssif_inc_stat(ssif_info, receive_errors);
+ } else {
+ ssif_inc_stat(ssif_info, received_messages);
+ ssif_inc_stat(ssif_info, received_message_parts);
+ }
+
+
+ continue_op:
+ if (ssif_info->ssif_debug & SSIF_DEBUG_STATE)
+ pr_info(PFX "DONE 1: state = %d, result=%d.\n",
+ ssif_info->ssif_state, result);
+
+ flags = ipmi_ssif_lock_cond(ssif_info, &oflags);
+ msg = ssif_info->curr_msg;
+ if (msg) {
+ msg->rsp_size = len;
+ if (msg->rsp_size > IPMI_MAX_MSG_LENGTH)
+ msg->rsp_size = IPMI_MAX_MSG_LENGTH;
+ memcpy(msg->rsp, data, msg->rsp_size);
+ ssif_info->curr_msg = NULL;
+ }
+
+ switch (ssif_info->ssif_state) {
+ case SSIF_NORMAL:
+ ipmi_ssif_unlock_cond(ssif_info, flags);
+ if (!msg)
+ break;
+
+ if (result < 0)
+ return_hosed_msg(ssif_info, msg);
+ else
+ deliver_recv_msg(ssif_info, msg);
+ break;
+
+ case SSIF_GETTING_FLAGS:
+ /* We got the flags from the SSIF, now handle them. */
+ if ((result < 0) || (len < 4) || (data[2] != 0)) {
+ /*
+ * Error fetching flags, or invalid length,
+ * just give up for now.
+ */
+ ssif_info->ssif_state = SSIF_NORMAL;
+ ipmi_ssif_unlock_cond(ssif_info, flags);
+ pr_warn(PFX "Error getting flags: %d %d, %x\n",
+ result, len, data[2]);
+ } else if (data[0] != (IPMI_NETFN_APP_REQUEST | 1) << 2
+ || data[1] != IPMI_GET_MSG_FLAGS_CMD) {
+ pr_warn(PFX "Invalid response getting flags: %x %x\n",
+ data[0], data[1]);
+ } else {
+ ssif_inc_stat(ssif_info, flag_fetches);
+ ssif_info->msg_flags = data[3];
+ handle_flags(ssif_info, flags);
+ }
+ break;
+
+ case SSIF_CLEARING_FLAGS:
+ /* We cleared the flags. */
+ if ((result < 0) || (len < 3) || (data[2] != 0)) {
+ /* Error clearing flags */
+ pr_warn(PFX "Error clearing flags: %d %d, %x\n",
+ result, len, data[2]);
+ } else if (data[0] != (IPMI_NETFN_APP_REQUEST | 1) << 2
+ || data[1] != IPMI_CLEAR_MSG_FLAGS_CMD) {
+ pr_warn(PFX "Invalid response clearing flags: %x %x\n",
+ data[0], data[1]);
+ }
+ ssif_info->ssif_state = SSIF_NORMAL;
+ ipmi_ssif_unlock_cond(ssif_info, flags);
+ break;
+
+ case SSIF_GETTING_EVENTS:
+ if ((result < 0) || (len < 3) || (msg->rsp[2] != 0)) {
+ /* Error getting event, probably done. */
+ msg->done(msg);
+
+ /* Take off the event flag. */
+ ssif_info->msg_flags &= ~EVENT_MSG_BUFFER_FULL;
+ handle_flags(ssif_info, flags);
+ } else if (msg->rsp[0] != (IPMI_NETFN_APP_REQUEST | 1) << 2
+ || msg->rsp[1] != IPMI_READ_EVENT_MSG_BUFFER_CMD) {
+ pr_warn(PFX "Invalid response getting events: %x %x\n",
+ msg->rsp[0], msg->rsp[1]);
+ msg->done(msg);
+ /* Take off the event flag. */
+ ssif_info->msg_flags &= ~EVENT_MSG_BUFFER_FULL;
+ handle_flags(ssif_info, flags);
+ } else {
+ handle_flags(ssif_info, flags);
+ ssif_inc_stat(ssif_info, events);
+ deliver_recv_msg(ssif_info, msg);
+ }
+ break;
+
+ case SSIF_GETTING_MESSAGES:
+ if ((result < 0) || (len < 3) || (msg->rsp[2] != 0)) {
+ /* Error getting event, probably done. */
+ msg->done(msg);
+
+ /* Take off the msg flag. */
+ ssif_info->msg_flags &= ~RECEIVE_MSG_AVAIL;
+ handle_flags(ssif_info, flags);
+ } else if (msg->rsp[0] != (IPMI_NETFN_APP_REQUEST | 1) << 2
+ || msg->rsp[1] != IPMI_GET_MSG_CMD) {
+ pr_warn(PFX "Invalid response clearing flags: %x %x\n",
+ msg->rsp[0], msg->rsp[1]);
+ msg->done(msg);
+
+ /* Take off the msg flag. */
+ ssif_info->msg_flags &= ~RECEIVE_MSG_AVAIL;
+ handle_flags(ssif_info, flags);
+ } else {
+ ssif_inc_stat(ssif_info, incoming_messages);
+ handle_flags(ssif_info, flags);
+ deliver_recv_msg(ssif_info, msg);
+ }
+ break;
+ }
+
+ flags = ipmi_ssif_lock_cond(ssif_info, &oflags);
+ if (SSIF_IDLE(ssif_info) && !ssif_info->stopping) {
+ if (ssif_info->req_events)
+ start_event_fetch(ssif_info, flags);
+ else if (ssif_info->req_flags)
+ start_flag_fetch(ssif_info, flags);
+ else
+ start_next_msg(ssif_info, flags);
+ } else
+ ipmi_ssif_unlock_cond(ssif_info, flags);
+
+ if (ssif_info->ssif_debug & SSIF_DEBUG_STATE)
+ pr_info(PFX "DONE 2: state = %d.\n", ssif_info->ssif_state);
+}
+
+static void msg_written_handler(struct ssif_info *ssif_info, int result,
+ unsigned char *data, unsigned int len)
+{
+ int rv;
+
+ /* We are single-threaded here, so no need for a lock. */
+ if (result < 0) {
+ ssif_info->retries_left--;
+ if (ssif_info->retries_left > 0) {
+ if (!start_resend(ssif_info)) {
+ ssif_inc_stat(ssif_info, send_retries);
+ return;
+ }
+ /* request failed, just return the error. */
+ ssif_inc_stat(ssif_info, send_errors);
+
+ if (ssif_info->ssif_debug & SSIF_DEBUG_MSG)
+ pr_info(PFX
+ "Out of retries in msg_written_handler\n");
+ msg_done_handler(ssif_info, -EIO, NULL, 0);
+ return;
+ }
+
+ ssif_inc_stat(ssif_info, send_errors);
+
+ /*
+ * Got an error on transmit, let the done routine
+ * handle it.
+ */
+ if (ssif_info->ssif_debug & SSIF_DEBUG_MSG)
+ pr_info("Error in msg_written_handler: %d\n", result);
+
+ msg_done_handler(ssif_info, result, NULL, 0);
+ return;
+ }
+
+ if (ssif_info->multi_data) {
+ /*
+ * In the middle of a multi-data write. See the comment
+ * in the SSIF_MULTI_n_PART case in the probe function
+ * for details on the intricacies of this.
+ */
+ int left;
+
+ ssif_inc_stat(ssif_info, sent_messages_parts);
+
+ left = ssif_info->multi_len - ssif_info->multi_pos;
+ if (left > 32)
+ left = 32;
+ /* Length byte. */
+ ssif_info->multi_data[ssif_info->multi_pos] = left;
+ ssif_info->multi_pos += left;
+ if (left < 32)
+ /*
+ * Write is finished. Note that we must end
+ * with a write of less than 32 bytes to
+ * complete the transaction, even if it is
+ * zero bytes.
+ */
+ ssif_info->multi_data = NULL;
+
+ rv = ssif_i2c_send(ssif_info, msg_written_handler,
+ I2C_SMBUS_WRITE,
+ SSIF_IPMI_MULTI_PART_REQUEST_MIDDLE,
+ ssif_info->multi_data + ssif_info->multi_pos,
+ I2C_SMBUS_BLOCK_DATA);
+ if (rv < 0) {
+ /* request failed, just return the error. */
+ ssif_inc_stat(ssif_info, send_errors);
+
+ if (ssif_info->ssif_debug & SSIF_DEBUG_MSG)
+ pr_info("Error from i2c_non_blocking_op(3)\n");
+ msg_done_handler(ssif_info, -EIO, NULL, 0);
+ }
+ } else {
+ unsigned long oflags, *flags;
+ bool got_alert;
+
+ ssif_inc_stat(ssif_info, sent_messages);
+ ssif_inc_stat(ssif_info, sent_messages_parts);
+
+ flags = ipmi_ssif_lock_cond(ssif_info, &oflags);
+ got_alert = ssif_info->got_alert;
+ if (got_alert) {
+ ssif_info->got_alert = false;
+ ssif_info->waiting_alert = false;
+ }
+
+ if (got_alert) {
+ ipmi_ssif_unlock_cond(ssif_info, flags);
+ /* The alert already happened, try now. */
+ retry_timeout((unsigned long) ssif_info);
+ } else {
+ /* Wait a jiffie then request the next message */
+ ssif_info->waiting_alert = true;
+ ssif_info->retries_left = SSIF_RECV_RETRIES;
+ ssif_info->rtc_us_timer = SSIF_MSG_PART_USEC;
+ mod_timer(&ssif_info->retry_timer,
+ jiffies + SSIF_MSG_PART_JIFFIES);
+ ipmi_ssif_unlock_cond(ssif_info, flags);
+ }
+ }
+}
+
+static int start_resend(struct ssif_info *ssif_info)
+{
+ int rv;
+ int command;
+
+ ssif_info->got_alert = false;
+
+ if (ssif_info->data_len > 32) {
+ command = SSIF_IPMI_MULTI_PART_REQUEST_START;
+ ssif_info->multi_data = ssif_info->data;
+ ssif_info->multi_len = ssif_info->data_len;
+ /*
+ * Subtle thing, this is 32, not 33, because we will
+ * overwrite the thing at position 32 (which was just
+ * transmitted) with the new length.
+ */
+ ssif_info->multi_pos = 32;
+ ssif_info->data[0] = 32;
+ } else {
+ ssif_info->multi_data = NULL;
+ command = SSIF_IPMI_REQUEST;
+ ssif_info->data[0] = ssif_info->data_len;
+ }
+
+ rv = ssif_i2c_send(ssif_info, msg_written_handler, I2C_SMBUS_WRITE,
+ command, ssif_info->data, I2C_SMBUS_BLOCK_DATA);
+ if (rv && (ssif_info->ssif_debug & SSIF_DEBUG_MSG))
+ pr_info("Error from i2c_non_blocking_op(4)\n");
+ return rv;
+}
+
+static int start_send(struct ssif_info *ssif_info,
+ unsigned char *data,
+ unsigned int len)
+{
+ if (len > IPMI_MAX_MSG_LENGTH)
+ return -E2BIG;
+ if (len > ssif_info->max_xmit_msg_size)
+ return -E2BIG;
+
+ ssif_info->retries_left = SSIF_SEND_RETRIES;
+ memcpy(ssif_info->data + 1, data, len);
+ ssif_info->data_len = len;
+ return start_resend(ssif_info);
+}
+
+/* Must be called with the message lock held. */
+static void start_next_msg(struct ssif_info *ssif_info, unsigned long *flags)
+{
+ struct ipmi_smi_msg *msg;
+ unsigned long oflags;
+
+ restart:
+ if (!SSIF_IDLE(ssif_info)) {
+ ipmi_ssif_unlock_cond(ssif_info, flags);
+ return;
+ }
+
+ if (!ssif_info->waiting_msg) {
+ ssif_info->curr_msg = NULL;
+ ipmi_ssif_unlock_cond(ssif_info, flags);
+ } else {
+ int rv;
+
+ ssif_info->curr_msg = ssif_info->waiting_msg;
+ ssif_info->waiting_msg = NULL;
+ ipmi_ssif_unlock_cond(ssif_info, flags);
+ rv = start_send(ssif_info,
+ ssif_info->curr_msg->data,
+ ssif_info->curr_msg->data_size);
+ if (rv) {
+ msg = ssif_info->curr_msg;
+ ssif_info->curr_msg = NULL;
+ return_hosed_msg(ssif_info, msg);
+ flags = ipmi_ssif_lock_cond(ssif_info, &oflags);
+ goto restart;
+ }
+ }
+}
+
+static void sender(void *send_info,
+ struct ipmi_smi_msg *msg)
+{
+ struct ssif_info *ssif_info = (struct ssif_info *) send_info;
+ unsigned long oflags, *flags;
+
+ BUG_ON(ssif_info->waiting_msg);
+ ssif_info->waiting_msg = msg;
+
+ flags = ipmi_ssif_lock_cond(ssif_info, &oflags);
+ start_next_msg(ssif_info, flags);
+
+ if (ssif_info->ssif_debug & SSIF_DEBUG_TIMING) {
+ struct timeval t;
+
+ do_gettimeofday(&t);
+ pr_info("**Enqueue %02x %02x: %ld.%6.6ld\n",
+ msg->data[0], msg->data[1],
+ (long) t.tv_sec, (long) t.tv_usec);
+ }
+}
+
+static int get_smi_info(void *send_info, struct ipmi_smi_info *data)
+{
+ struct ssif_info *ssif_info = send_info;
+
+ data->addr_src = ssif_info->addr_source;
+ data->dev = &ssif_info->client->dev;
+ data->addr_info = ssif_info->addr_info;
+ get_device(data->dev);
+
+ return 0;
+}
+
+/*
+ * Instead of having our own timer to periodically check the message
+ * flags, we let the message handler drive us.
+ */
+static void request_events(void *send_info)
+{
+ struct ssif_info *ssif_info = (struct ssif_info *) send_info;
+ unsigned long oflags, *flags;
+
+ if (!ssif_info->has_event_buffer)
+ return;
+
+ flags = ipmi_ssif_lock_cond(ssif_info, &oflags);
+ /*
+ * Request flags first, not events, because the lower layer
+ * doesn't have a way to send an attention. But make sure
+ * event checking still happens.
+ */
+ ssif_info->req_events = true;
+ if (SSIF_IDLE(ssif_info))
+ start_flag_fetch(ssif_info, flags);
+ else {
+ ssif_info->req_flags = true;
+ ipmi_ssif_unlock_cond(ssif_info, flags);
+ }
+}
+
+static int inc_usecount(void *send_info)
+{
+ struct ssif_info *ssif_info = send_info;
+
+ if (!i2c_get_adapter(ssif_info->client->adapter->nr))
+ return -ENODEV;
+
+ i2c_use_client(ssif_info->client);
+ return 0;
+}
+
+static void dec_usecount(void *send_info)
+{
+ struct ssif_info *ssif_info = send_info;
+
+ i2c_release_client(ssif_info->client);
+ i2c_put_adapter(ssif_info->client->adapter);
+}
+
+static int ssif_start_processing(void *send_info,
+ ipmi_smi_t intf)
+{
+ struct ssif_info *ssif_info = send_info;
+
+ ssif_info->intf = intf;
+
+ return 0;
+}
+
+#define MAX_SSIF_BMCS 4
+
+static unsigned short addr[MAX_SSIF_BMCS];
+static int num_addrs;
+module_param_array(addr, ushort, &num_addrs, 0);
+MODULE_PARM_DESC(addr, "The addresses to scan for IPMI BMCs on the SSIFs.");
+
+static char *adapter_name[MAX_SSIF_BMCS];
+static int num_adapter_names;
+module_param_array(adapter_name, charp, &num_adapter_names, 0);
+MODULE_PARM_DESC(adapter_name, "The string name of the I2C device that has the BMC. By default all devices are scanned.");
+
+static int slave_addrs[MAX_SSIF_BMCS];
+static int num_slave_addrs;
+module_param_array(slave_addrs, int, &num_slave_addrs, 0);
+MODULE_PARM_DESC(slave_addrs,
+ "The default IPMB slave address for the controller.");
+
+/*
+ * Bit 0 enables message debugging, bit 1 enables state debugging, and
+ * bit 2 enables timing debugging. This is an array indexed by
+ * interface number"
+ */
+static int dbg[MAX_SSIF_BMCS];
+static int num_dbg;
+module_param_array(dbg, int, &num_dbg, 0);
+MODULE_PARM_DESC(dbg, "Turn on debugging.");
+
+static bool ssif_dbg_probe;
+module_param_named(dbg_probe, ssif_dbg_probe, bool, 0);
+MODULE_PARM_DESC(dbg_probe, "Enable debugging of probing of adapters.");
+
+static int use_thread;
+module_param(use_thread, int, 0);
+MODULE_PARM_DESC(use_thread, "Use the thread interface.");
+
+static bool ssif_tryacpi = 1;
+module_param_named(tryacpi, ssif_tryacpi, bool, 0);
+MODULE_PARM_DESC(tryacpi, "Setting this to zero will disable the default scan of the interfaces identified via ACPI");
+
+static bool ssif_trydmi = 1;
+module_param_named(trydmi, ssif_trydmi, bool, 0);
+MODULE_PARM_DESC(trydmi, "Setting this to zero will disable the default scan of the interfaces identified via DMI (SMBIOS)");
+
+static DEFINE_MUTEX(ssif_infos_mutex);
+static LIST_HEAD(ssif_infos);
+
+static int ssif_remove(struct i2c_client *client)
+{
+ struct ssif_info *ssif_info = i2c_get_clientdata(client);
+ int rv;
+
+ if (!ssif_info)
+ return 0;
+
+ /*
+ * After this point, we won't deliver anything asychronously
+ * to the message handler. We can unregister ourself.
+ */
+ rv = ipmi_unregister_smi(ssif_info->intf);
+ if (rv) {
+ pr_err(PFX "Unable to unregister device: errno=%d\n", rv);
+ return rv;
+ }
+ ssif_info->intf = NULL;
+
+ /* make sure the driver is not looking for flags any more. */
+ while (ssif_info->ssif_state != SSIF_NORMAL)
+ schedule_timeout(1);
+
+ ssif_info->stopping = true;
+ del_timer_sync(&ssif_info->retry_timer);
+ if (ssif_info->thread) {
+ complete(&ssif_info->wake_thread);
+ kthread_stop(ssif_info->thread);
+ }
+
+ /*
+ * No message can be outstanding now, we have removed the
+ * upper layer and it permitted us to do so.
+ */
+ kfree(ssif_info);
+ return 0;
+}
+
+static int do_cmd(struct i2c_client *client, int len, unsigned char *msg,
+ int *resp_len, unsigned char *resp)
+{
+ int retry_cnt;
+ int ret;
+
+ retry_cnt = SSIF_SEND_RETRIES;
+ retry1:
+ ret = i2c_smbus_write_block_data(client, SSIF_IPMI_REQUEST, len, msg);
+ if (ret) {
+ retry_cnt--;
+ if (retry_cnt > 0)
+ goto retry1;
+ return -ENODEV;
+ }
+
+ ret = -ENODEV;
+ retry_cnt = SSIF_RECV_RETRIES;
+ while (retry_cnt > 0) {
+ ret = i2c_smbus_read_block_data(client, SSIF_IPMI_RESPONSE,
+ resp);
+ if (ret > 0)
+ break;
+ msleep(SSIF_MSG_MSEC);
+ retry_cnt--;
+ if (retry_cnt <= 0)
+ break;
+ }
+
+ if (ret > 0) {
+ /* Validate that the response is correct. */
+ if (ret < 3 ||
+ (resp[0] != (msg[0] | (1 << 2))) ||
+ (resp[1] != msg[1]))
+ ret = -EINVAL;
+ else {
+ *resp_len = ret;
+ ret = 0;
+ }
+ }
+
+ return ret;
+}
+
+static int ssif_detect(struct i2c_client *client, struct i2c_board_info *info)
+{
+ unsigned char *resp;
+ unsigned char msg[3];
+ int rv;
+ int len;
+
+ resp = kmalloc(IPMI_MAX_MSG_LENGTH, GFP_KERNEL);
+ if (!resp)
+ return -ENOMEM;
+
+ /* Do a Get Device ID command, since it is required. */
+ msg[0] = IPMI_NETFN_APP_REQUEST << 2;
+ msg[1] = IPMI_GET_DEVICE_ID_CMD;
+ rv = do_cmd(client, 2, msg, &len, resp);
+ if (rv)
+ rv = -ENODEV;
+ else
+ strlcpy(info->type, DEVICE_NAME, I2C_NAME_SIZE);
+ kfree(resp);
+ return rv;
+}
+
+static int smi_type_proc_show(struct seq_file *m, void *v)
+{
+ seq_puts(m, "ssif\n");
+
+ return 0;
+}
+
+static int smi_type_proc_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, smi_type_proc_show, inode->i_private);
+}
+
+static const struct file_operations smi_type_proc_ops = {
+ .open = smi_type_proc_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static int smi_stats_proc_show(struct seq_file *m, void *v)
+{
+ struct ssif_info *ssif_info = m->private;
+
+ seq_printf(m, "sent_messages: %u\n",
+ ssif_get_stat(ssif_info, sent_messages));
+ seq_printf(m, "sent_messages_parts: %u\n",
+ ssif_get_stat(ssif_info, sent_messages_parts));
+ seq_printf(m, "send_retries: %u\n",
+ ssif_get_stat(ssif_info, send_retries));
+ seq_printf(m, "send_errors: %u\n",
+ ssif_get_stat(ssif_info, send_errors));
+ seq_printf(m, "received_messages: %u\n",
+ ssif_get_stat(ssif_info, received_messages));
+ seq_printf(m, "received_message_parts: %u\n",
+ ssif_get_stat(ssif_info, received_message_parts));
+ seq_printf(m, "receive_retries: %u\n",
+ ssif_get_stat(ssif_info, receive_retries));
+ seq_printf(m, "receive_errors: %u\n",
+ ssif_get_stat(ssif_info, receive_errors));
+ seq_printf(m, "flag_fetches: %u\n",
+ ssif_get_stat(ssif_info, flag_fetches));
+ seq_printf(m, "hosed: %u\n",
+ ssif_get_stat(ssif_info, hosed));
+ seq_printf(m, "events: %u\n",
+ ssif_get_stat(ssif_info, events));
+ seq_printf(m, "watchdog_pretimeouts: %u\n",
+ ssif_get_stat(ssif_info, watchdog_pretimeouts));
+ seq_printf(m, "alerts: %u\n",
+ ssif_get_stat(ssif_info, alerts));
+ return 0;
+}
+
+static int smi_stats_proc_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, smi_stats_proc_show, PDE_DATA(inode));
+}
+
+static const struct file_operations smi_stats_proc_ops = {
+ .open = smi_stats_proc_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static int strcmp_nospace(char *s1, char *s2)
+{
+ while (*s1 && *s2) {
+ while (isspace(*s1))
+ s1++;
+ while (isspace(*s2))
+ s2++;
+ if (*s1 > *s2)
+ return 1;
+ if (*s1 < *s2)
+ return -1;
+ s1++;
+ s2++;
+ }
+ return 0;
+}
+
+static struct ssif_addr_info *ssif_info_find(unsigned short addr,
+ char *adapter_name,
+ bool match_null_name)
+{
+ struct ssif_addr_info *info, *found = NULL;
+
+restart:
+ list_for_each_entry(info, &ssif_infos, link) {
+ if (info->binfo.addr == addr) {
+ if (info->adapter_name || adapter_name) {
+ if (!info->adapter_name != !adapter_name) {
+ /* One is NULL and one is not */
+ continue;
+ }
+ if (adapter_name &&
+ strcmp_nospace(info->adapter_name,
+ adapter_name))
+ /* Names do not match */
+ continue;
+ }
+ found = info;
+ break;
+ }
+ }
+
+ if (!found && match_null_name) {
+ /* Try to get an exact match first, then try with a NULL name */
+ adapter_name = NULL;
+ match_null_name = false;
+ goto restart;
+ }
+
+ return found;
+}
+
+static bool check_acpi(struct ssif_info *ssif_info, struct device *dev)
+{
+#ifdef CONFIG_ACPI
+ acpi_handle acpi_handle;
+
+ acpi_handle = ACPI_HANDLE(dev);
+ if (acpi_handle) {
+ ssif_info->addr_source = SI_ACPI;
+ ssif_info->addr_info.acpi_info.acpi_handle = acpi_handle;
+ return true;
+ }
+#endif
+ return false;
+}
+
+/*
+ * 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 int ssif_probe(struct i2c_client *client, const struct i2c_device_id *id)
+{
+ unsigned char msg[3];
+ unsigned char *resp;
+ struct ssif_info *ssif_info;
+ int rv = 0;
+ int len;
+ int i;
+ u8 slave_addr = 0;
+ struct ssif_addr_info *addr_info = NULL;
+
+
+ resp = kmalloc(IPMI_MAX_MSG_LENGTH, GFP_KERNEL);
+ if (!resp)
+ return -ENOMEM;
+
+ ssif_info = kzalloc(sizeof(*ssif_info), GFP_KERNEL);
+ if (!ssif_info) {
+ kfree(resp);
+ return -ENOMEM;
+ }
+
+ if (!check_acpi(ssif_info, &client->dev)) {
+ addr_info = ssif_info_find(client->addr, client->adapter->name,
+ true);
+ if (!addr_info) {
+ /* Must have come in through sysfs. */
+ ssif_info->addr_source = SI_HOTMOD;
+ } else {
+ ssif_info->addr_source = addr_info->addr_src;
+ ssif_info->ssif_debug = addr_info->debug;
+ ssif_info->addr_info = addr_info->addr_info;
+ slave_addr = addr_info->slave_addr;
+ }
+ }
+
+ pr_info(PFX "Trying %s-specified SSIF interface at i2c address 0x%x, adapter %s, slave address 0x%x\n",
+ ipmi_addr_src_to_str(ssif_info->addr_source),
+ client->addr, client->adapter->name, slave_addr);
+
+ /*
+ * 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;
+ rv = do_cmd(client, 2, msg, &len, resp);
+ if (rv)
+ goto out;
+
+ rv = ipmi_demangle_device_id(resp, len, &ssif_info->device_id);
+ if (rv)
+ goto out;
+
+ ssif_info->client = client;
+ i2c_set_clientdata(client, ssif_info);
+
+ /* Now check for system interface capabilities */
+ msg[0] = IPMI_NETFN_APP_REQUEST << 2;
+ msg[1] = IPMI_GET_SYSTEM_INTERFACE_CAPABILITIES_CMD;
+ msg[2] = 0; /* SSIF */
+ rv = do_cmd(client, 3, msg, &len, resp);
+ if (!rv && (len >= 3) && (resp[2] == 0)) {
+ if (len < 7) {
+ if (ssif_dbg_probe)
+ pr_info(PFX "SSIF info too short: %d\n", len);
+ goto no_support;
+ }
+
+ /* Got a good SSIF response, handle it. */
+ ssif_info->max_xmit_msg_size = resp[5];
+ ssif_info->max_recv_msg_size = resp[6];
+ ssif_info->multi_support = (resp[4] >> 6) & 0x3;
+ ssif_info->supports_pec = (resp[4] >> 3) & 0x1;
+
+ /* Sanitize the data */
+ switch (ssif_info->multi_support) {
+ case SSIF_NO_MULTI:
+ if (ssif_info->max_xmit_msg_size > 32)
+ ssif_info->max_xmit_msg_size = 32;
+ if (ssif_info->max_recv_msg_size > 32)
+ ssif_info->max_recv_msg_size = 32;
+ break;
+
+ case SSIF_MULTI_2_PART:
+ if (ssif_info->max_xmit_msg_size > 63)
+ ssif_info->max_xmit_msg_size = 63;
+ if (ssif_info->max_recv_msg_size > 62)
+ ssif_info->max_recv_msg_size = 62;
+ break;
+
+ case SSIF_MULTI_n_PART:
+ /*
+ * The specification is rather confusing at
+ * this point, but I think I understand what
+ * is meant. At least I have a workable
+ * solution. With multi-part messages, you
+ * cannot send a message that is a multiple of
+ * 32-bytes in length, because the start and
+ * middle messages are 32-bytes and the end
+ * message must be at least one byte. You
+ * can't fudge on an extra byte, that would
+ * screw up things like fru data writes. So
+ * we limit the length to 63 bytes. That way
+ * a 32-byte message gets sent as a single
+ * part. A larger message will be a 32-byte
+ * start and the next message is always going
+ * to be 1-31 bytes in length. Not ideal, but
+ * it should work.
+ */
+ if (ssif_info->max_xmit_msg_size > 63)
+ ssif_info->max_xmit_msg_size = 63;
+ break;
+
+ default:
+ /* Data is not sane, just give up. */
+ goto no_support;
+ }
+ } else {
+ no_support:
+ /* Assume no multi-part or PEC support */
+ pr_info(PFX "Error fetching SSIF: %d %d %2.2x, your system probably doesn't support this command so using defaults\n",
+ rv, len, resp[2]);
+
+ ssif_info->max_xmit_msg_size = 32;
+ ssif_info->max_recv_msg_size = 32;
+ ssif_info->multi_support = SSIF_NO_MULTI;
+ ssif_info->supports_pec = 0;
+ }
+
+ /* Make sure the NMI timeout is cleared. */
+ msg[0] = IPMI_NETFN_APP_REQUEST << 2;
+ msg[1] = IPMI_CLEAR_MSG_FLAGS_CMD;
+ msg[2] = WDT_PRE_TIMEOUT_INT;
+ rv = do_cmd(client, 3, msg, &len, resp);
+ if (rv || (len < 3) || (resp[2] != 0))
+ pr_warn(PFX "Unable to clear message flags: %d %d %2.2x\n",
+ rv, len, resp[2]);
+
+ /* Attempt to enable the event buffer. */
+ msg[0] = IPMI_NETFN_APP_REQUEST << 2;
+ msg[1] = IPMI_GET_BMC_GLOBAL_ENABLES_CMD;
+ rv = do_cmd(client, 2, msg, &len, resp);
+ if (rv || (len < 4) || (resp[2] != 0)) {
+ pr_warn(PFX "Error getting global enables: %d %d %2.2x\n",
+ rv, len, resp[2]);
+ rv = 0; /* Not fatal */
+ goto found;
+ }
+
+ ssif_info->global_enables = resp[3];
+
+ if (resp[3] & IPMI_BMC_EVT_MSG_BUFF) {
+ ssif_info->has_event_buffer = true;
+ /* buffer is already enabled, nothing to do. */
+ goto found;
+ }
+
+ msg[0] = IPMI_NETFN_APP_REQUEST << 2;
+ msg[1] = IPMI_SET_BMC_GLOBAL_ENABLES_CMD;
+ msg[2] = ssif_info->global_enables | IPMI_BMC_EVT_MSG_BUFF;
+ rv = do_cmd(client, 3, msg, &len, resp);
+ if (rv || (len < 2)) {
+ pr_warn(PFX "Error setting global enables: %d %d %2.2x\n",
+ rv, len, resp[2]);
+ rv = 0; /* Not fatal */
+ goto found;
+ }
+
+ if (resp[2] == 0) {
+ /* A successful return means the event buffer is supported. */
+ ssif_info->has_event_buffer = true;
+ ssif_info->global_enables |= IPMI_BMC_EVT_MSG_BUFF;
+ }
+
+ msg[0] = IPMI_NETFN_APP_REQUEST << 2;
+ msg[1] = IPMI_SET_BMC_GLOBAL_ENABLES_CMD;
+ msg[2] = ssif_info->global_enables | IPMI_BMC_RCV_MSG_INTR;
+ rv = do_cmd(client, 3, msg, &len, resp);
+ if (rv || (len < 2)) {
+ pr_warn(PFX "Error setting global enables: %d %d %2.2x\n",
+ rv, len, resp[2]);
+ rv = 0; /* Not fatal */
+ goto found;
+ }
+
+ if (resp[2] == 0) {
+ /* A successful return means the alert is supported. */
+ ssif_info->supports_alert = true;
+ ssif_info->global_enables |= IPMI_BMC_RCV_MSG_INTR;
+ }
+
+ found:
+ ssif_info->intf_num = atomic_inc_return(&next_intf);
+
+ if (ssif_dbg_probe) {
+ pr_info("ssif_probe: i2c_probe found device at i2c address %x\n",
+ client->addr);
+ }
+
+ spin_lock_init(&ssif_info->lock);
+ ssif_info->ssif_state = SSIF_NORMAL;
+ init_timer(&ssif_info->retry_timer);
+ ssif_info->retry_timer.data = (unsigned long) ssif_info;
+ ssif_info->retry_timer.function = retry_timeout;
+
+ for (i = 0; i < SSIF_NUM_STATS; i++)
+ atomic_set(&ssif_info->stats[i], 0);
+
+ if (ssif_info->supports_pec)
+ ssif_info->client->flags |= I2C_CLIENT_PEC;
+
+ ssif_info->handlers.owner = THIS_MODULE;
+ ssif_info->handlers.start_processing = ssif_start_processing;
+ ssif_info->handlers.get_smi_info = get_smi_info;
+ ssif_info->handlers.sender = sender;
+ ssif_info->handlers.request_events = request_events;
+ ssif_info->handlers.inc_usecount = inc_usecount;
+ ssif_info->handlers.dec_usecount = dec_usecount;
+
+ {
+ unsigned int thread_num;
+
+ thread_num = ((ssif_info->client->adapter->nr << 8) |
+ ssif_info->client->addr);
+ init_completion(&ssif_info->wake_thread);
+ ssif_info->thread = kthread_run(ipmi_ssif_thread, ssif_info,
+ "kssif%4.4x", thread_num);
+ if (IS_ERR(ssif_info->thread)) {
+ rv = PTR_ERR(ssif_info->thread);
+ dev_notice(&ssif_info->client->dev,
+ "Could not start kernel thread: error %d\n",
+ rv);
+ goto out;
+ }
+ }
+
+ rv = ipmi_register_smi(&ssif_info->handlers,
+ ssif_info,
+ &ssif_info->device_id,
+ &ssif_info->client->dev,
+ slave_addr);
+ if (rv) {
+ pr_err(PFX "Unable to register device: error %d\n", rv);
+ goto out;
+ }
+
+ rv = ipmi_smi_add_proc_entry(ssif_info->intf, "type",
+ &smi_type_proc_ops,
+ ssif_info);
+ if (rv) {
+ pr_err(PFX "Unable to create proc entry: %d\n", rv);
+ goto out_err_unreg;
+ }
+
+ rv = ipmi_smi_add_proc_entry(ssif_info->intf, "ssif_stats",
+ &smi_stats_proc_ops,
+ ssif_info);
+ if (rv) {
+ pr_err(PFX "Unable to create proc entry: %d\n", rv);
+ goto out_err_unreg;
+ }
+
+ out:
+ if (rv)
+ kfree(ssif_info);
+ kfree(resp);
+ return rv;
+
+ out_err_unreg:
+ ipmi_unregister_smi(ssif_info->intf);
+ goto out;
+}
+
+static int ssif_adapter_handler(struct device *adev, void *opaque)
+{
+ struct ssif_addr_info *addr_info = opaque;
+
+ if (adev->type != &i2c_adapter_type)
+ return 0;
+
+ i2c_new_device(to_i2c_adapter(adev), &addr_info->binfo);
+
+ if (!addr_info->adapter_name)
+ return 1; /* Only try the first I2C adapter by default. */
+ return 0;
+}
+
+static int new_ssif_client(int addr, char *adapter_name,
+ int debug, int slave_addr,
+ enum ipmi_addr_src addr_src)
+{
+ struct ssif_addr_info *addr_info;
+ int rv = 0;
+
+ mutex_lock(&ssif_infos_mutex);
+ if (ssif_info_find(addr, adapter_name, false)) {
+ rv = -EEXIST;
+ goto out_unlock;
+ }
+
+ addr_info = kzalloc(sizeof(*addr_info), GFP_KERNEL);
+ if (!addr_info) {
+ rv = -ENOMEM;
+ goto out_unlock;
+ }
+
+ if (adapter_name) {
+ addr_info->adapter_name = kstrdup(adapter_name, GFP_KERNEL);
+ if (!addr_info->adapter_name) {
+ kfree(addr_info);
+ rv = -ENOMEM;
+ goto out_unlock;
+ }
+ }
+
+ strncpy(addr_info->binfo.type, DEVICE_NAME,
+ sizeof(addr_info->binfo.type));
+ addr_info->binfo.addr = addr;
+ addr_info->binfo.platform_data = addr_info;
+ addr_info->debug = debug;
+ addr_info->slave_addr = slave_addr;
+ addr_info->addr_src = addr_src;
+
+ list_add_tail(&addr_info->link, &ssif_infos);
+
+ if (initialized)
+ i2c_for_each_dev(addr_info, ssif_adapter_handler);
+ /* Otherwise address list will get it */
+
+out_unlock:
+ mutex_unlock(&ssif_infos_mutex);
+ return rv;
+}
+
+static void free_ssif_clients(void)
+{
+ struct ssif_addr_info *info, *tmp;
+
+ mutex_lock(&ssif_infos_mutex);
+ list_for_each_entry_safe(info, tmp, &ssif_infos, link) {
+ list_del(&info->link);
+ kfree(info->adapter_name);
+ kfree(info);
+ }
+ mutex_unlock(&ssif_infos_mutex);
+}
+
+static unsigned short *ssif_address_list(void)
+{
+ struct ssif_addr_info *info;
+ unsigned int count = 0, i;
+ unsigned short *address_list;
+
+ list_for_each_entry(info, &ssif_infos, link)
+ count++;
+
+ address_list = kzalloc(sizeof(*address_list) * (count + 1), GFP_KERNEL);
+ if (!address_list)
+ return NULL;
+
+ i = 0;
+ list_for_each_entry(info, &ssif_infos, link) {
+ unsigned short addr = info->binfo.addr;
+ int j;
+
+ for (j = 0; j < i; j++) {
+ if (address_list[j] == addr)
+ goto skip_addr;
+ }
+ address_list[i] = addr;
+skip_addr:
+ i++;
+ }
+ address_list[i] = I2C_CLIENT_END;
+
+ return address_list;
+}
+
+#ifdef CONFIG_ACPI
+static struct acpi_device_id ssif_acpi_match[] = {
+ { "IPI0001", 0 },
+ { },
+};
+MODULE_DEVICE_TABLE(acpi, ssif_acpi_match);
+
+/*
+ * Once we get an ACPI failure, we don't try any more, because we go
+ * through the tables sequentially. Once we don't find a table, there
+ * are no more.
+ */
+static int acpi_failure;
+
+/*
+ * Defined in the IPMI 2.0 spec.
+ */
+struct SPMITable {
+ s8 Signature[4];
+ u32 Length;
+ u8 Revision;
+ u8 Checksum;
+ s8 OEMID[6];
+ s8 OEMTableID[8];
+ s8 OEMRevision[4];
+ s8 CreatorID[4];
+ s8 CreatorRevision[4];
+ u8 InterfaceType;
+ u8 IPMIlegacy;
+ s16 SpecificationRevision;
+
+ /*
+ * Bit 0 - SCI interrupt supported
+ * Bit 1 - I/O APIC/SAPIC
+ */
+ u8 InterruptType;
+
+ /*
+ * If bit 0 of InterruptType is set, then this is the SCI
+ * interrupt in the GPEx_STS register.
+ */
+ u8 GPE;
+
+ s16 Reserved;
+
+ /*
+ * If bit 1 of InterruptType is set, then this is the I/O
+ * APIC/SAPIC interrupt.
+ */
+ u32 GlobalSystemInterrupt;
+
+ /* The actual register address. */
+ struct acpi_generic_address addr;
+
+ u8 UID[4];
+
+ s8 spmi_id[1]; /* A '\0' terminated array starts here. */
+};
+
+static int try_init_spmi(struct SPMITable *spmi)
+{
+ unsigned short myaddr;
+
+ if (num_addrs >= MAX_SSIF_BMCS)
+ return -1;
+
+ if (spmi->IPMIlegacy != 1) {
+ pr_warn("IPMI: Bad SPMI legacy: %d\n", spmi->IPMIlegacy);
+ return -ENODEV;
+ }
+
+ if (spmi->InterfaceType != 4)
+ return -ENODEV;
+
+ if (spmi->addr.space_id != ACPI_ADR_SPACE_SMBUS) {
+ pr_warn(PFX "Invalid ACPI SSIF I/O Address type: %d\n",
+ spmi->addr.space_id);
+ return -EIO;
+ }
+
+ myaddr = spmi->addr.address >> 1;
+
+ return new_ssif_client(myaddr, NULL, 0, 0, SI_SPMI);
+}
+
+static void spmi_find_bmc(void)
+{
+ acpi_status status;
+ struct SPMITable *spmi;
+ int i;
+
+ if (acpi_disabled)
+ return;
+
+ if (acpi_failure)
+ return;
+
+ for (i = 0; ; i++) {
+ status = acpi_get_table(ACPI_SIG_SPMI, i+1,
+ (struct acpi_table_header **)&spmi);
+ if (status != AE_OK)
+ return;
+
+ try_init_spmi(spmi);
+ }
+}
+#else
+static void spmi_find_bmc(void) { }
+#endif
+
+#ifdef CONFIG_DMI
+static int decode_dmi(const struct dmi_device *dmi_dev)
+{
+ struct dmi_header *dm = dmi_dev->device_data;
+ u8 *data = (u8 *) dm;
+ u8 len = dm->length;
+ unsigned short myaddr;
+ int slave_addr;
+
+ if (num_addrs >= MAX_SSIF_BMCS)
+ return -1;
+
+ if (len < 9)
+ return -1;
+
+ if (data[0x04] != 4) /* Not SSIF */
+ return -1;
+
+ if ((data[8] >> 1) == 0) {
+ /*
+ * Some broken systems put the I2C address in
+ * the slave address field. We try to
+ * accommodate them here.
+ */
+ myaddr = data[6] >> 1;
+ slave_addr = 0;
+ } else {
+ myaddr = data[8] >> 1;
+ slave_addr = data[6];
+ }
+
+ return new_ssif_client(myaddr, NULL, 0, 0, SI_SMBIOS);
+}
+
+static void dmi_iterator(void)
+{
+ const struct dmi_device *dev = NULL;
+
+ while ((dev = dmi_find_device(DMI_DEV_TYPE_IPMI, NULL, dev)))
+ decode_dmi(dev);
+}
+#else
+static void dmi_iterator(void) { }
+#endif
+
+static const struct i2c_device_id ssif_id[] = {
+ { DEVICE_NAME, 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, ssif_id);
+
+static struct i2c_driver ssif_i2c_driver = {
+ .class = I2C_CLASS_HWMON,
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = DEVICE_NAME
+ },
+ .probe = ssif_probe,
+ .remove = ssif_remove,
+ .alert = ssif_alert,
+ .id_table = ssif_id,
+ .detect = ssif_detect
+};
+
+static int init_ipmi_ssif(void)
+{
+ int i;
+ int rv;
+
+ if (initialized)
+ return 0;
+
+ pr_info("IPMI SSIF Interface driver\n");
+
+ /* build list for i2c from addr list */
+ for (i = 0; i < num_addrs; i++) {
+ rv = new_ssif_client(addr[i], adapter_name[i],
+ dbg[i], slave_addrs[i],
+ SI_HARDCODED);
+ if (rv)
+ pr_err(PFX
+ "Couldn't add hardcoded device at addr 0x%x\n",
+ addr[i]);
+ }
+
+ if (ssif_tryacpi)
+ ssif_i2c_driver.driver.acpi_match_table =
+ ACPI_PTR(ssif_acpi_match);
+ if (ssif_trydmi)
+ dmi_iterator();
+ if (ssif_tryacpi)
+ spmi_find_bmc();
+
+ ssif_i2c_driver.address_list = ssif_address_list();
+
+ rv = i2c_add_driver(&ssif_i2c_driver);
+ if (!rv)
+ initialized = true;
+
+ return rv;
+}
+module_init(init_ipmi_ssif);
+
+static void cleanup_ipmi_ssif(void)
+{
+ if (!initialized)
+ return;
+
+ initialized = false;
+
+ i2c_del_driver(&ssif_i2c_driver);
+
+ free_ssif_clients();
+}
+module_exit(cleanup_ipmi_ssif);
+
+MODULE_AUTHOR("Todd C Davis <todd.c.davis@intel.com>, Corey Minyard <minyard@acm.org>");
+MODULE_DESCRIPTION("IPMI driver for management controllers on a SMBus");
+MODULE_LICENSE("GPL");