// SPDX-License-Identifier: GPL-2.0+
/*
* 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 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.
*/
#define pr_fmt(fmt) "ipmi_ssif: " fmt
#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>
#include <linux/time64.h>
#include "ipmi_si_sm.h"
#include "ipmi_dmi.h"
#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_MULTI_PART_REQUEST_END 8
#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 {
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 device *dev;
struct i2c_client *client;
struct i2c_client *added_client;
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 {
struct ipmi_smi *intf;
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;
struct timer_list retry_timer;
int retries_left;
/* Info from SSIF cmd */
unsigned char max_xmit_msg_size;
unsigned char max_recv_msg_size;
bool cmd8_works; /* See test_multipart_messages() for details. */
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 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)
{
if (msg->rsp_size < 0) {
return_hosed_msg(ssif_info, msg);
pr_err("%s: Malformed message: rsp_size = %d\n",
__func__, msg->rsp_size);
} else {
ipmi_smi_msg_received(ssif_info->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;
ipmi_ssif_unlock_cond(ssif_info, flags);
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;
ipmi_ssif_unlock_cond(ssif_info, flags);
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) {
/* Watchdog pre-timeout */
ssif_inc_stat(ssif_info, watchdog_pretimeouts);
start_clear_flags(ssif_info, flags);
ipmi_smi_watchdog_pretimeout(ssif_info->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(struct timer_list *t)
{
struct ssif_info *ssif_info = from_timer(ssif_info, t, retry_timer);
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, enum i2c_alert_protocol type,
unsigned int data)
{
struct ssif_info *ssif_info = i2c_get_clientdata(client);
unsigned long oflags, *flags;
bool do_get = false;
if (type != I2C_PROTOCOL_SMBUS_ALERT)
return;
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;
if (!ssif_info->stopping)
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;
data += 2;
for (i = 0; i < len; i++)
ssif_info->data[i] = data[i];
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("Middle message with no data\n");
goto continue_op;
}
blocknum = data[0];
len--;
data++;
if (blocknum != 0xff && len != 31) {
/* All blocks but the last must have 31 data bytes. */
result = -EIO;
if (ssif_info->ssif_debug & SSIF_DEBUG_MSG)
pr_info("Received middle message <31\n");
goto continue_op;
}
if (ssif_info->multi_len + len > 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;
}
for (i = 0; i < len; i++)
ssif_info->data[i + ssif_info->multi_len] = data[i];
ssif_info->multi_len += len;
if (blocknum == 0xff) {
/* End of read */
len = ssif_info->multi_len;
data = ssif_info->data;
} else if (blocknum != 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("Error from ssif_i2c_send\n");
result = -EIO;
} else
return;
}
}
continue_op:
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);
}
if (ssif_info->ssif_debug & SSIF_DEBUG_STATE)
pr_info("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("Error getting flags: %d %d, %x\n",
result, len, (len >= 3) ? data[2] : 0);
} else if (data[0] != (IPMI_NETFN_APP_REQUEST | 1) << 2
|| data[1] != IPMI_GET_MSG_FLAGS_CMD) {
/*
* Don't abort here, maybe it was a queued
* response to a previous command.
*/
ipmi_ssif_unlock_cond(ssif_info, flags);
pr_warn("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("Error clearing flags: %d %d, %x\n",
result, len, (len >= 3) ? data[2] : 0);
} else if (data[0] != (IPMI_NETFN_APP_REQUEST | 1) << 2
|| data[1] != IPMI_CLEAR_MSG_FLAGS_CMD) {
pr_warn("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("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("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("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("%s: Out of retries\n", __func__);
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, to_write;
unsigned char *data_to_send;
unsigned char cmd;
ssif_inc_stat(ssif_info, sent_messages_parts);
left = ssif_info->multi_len - ssif_info->multi_pos;
to_write = left;
if (to_write > 32)
to_write = 32;
/* Length byte. */
ssif_info->multi_data[ssif_info->multi_pos] = to_write;
data_to_send = ssif_info->multi_data + ssif_info->multi_pos;
ssif_info->multi_pos += to_write;
cmd = SSIF_IPMI_MULTI_PART_REQUEST_MIDDLE;
if (ssif_info->cmd8_works) {
if (left == to_write) {
cmd = SSIF_IPMI_MULTI_PART_REQUEST_END;
ssif_info->multi_data = NULL;
}
} else if (to_write < 32) {
ssif_info->multi_data = NULL;
}
rv = ssif_i2c_send(ssif_info, msg_written_handler,
I2C_SMBUS_WRITE, cmd,
data_to_send, 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 {
/* Ready to request the result. */
unsigned long oflags, *flags;
ssif_inc_stat(ssif_info, sent_messages);
ssif_inc_stat(ssif_info, sent_messages_parts);
flags = ipmi_ssif_lock_cond(ssif_info, &oflags);
if (ssif_info->got_alert) {
/* The result is already ready, just start it. */
ssif_info->got_alert = false;
ipmi_ssif_unlock_cond(ssif_info, flags);
start_get(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;
if (!ssif_info->stopping)
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 timespec64 t;
ktime_get_real_ts64(&t);
pr_info("**Enqueue %02x %02x: %lld.%6.6ld\n",
msg->data[0], msg->data[1],
(long long)t.tv_sec, (long)t.tv_nsec / NSEC_PER_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 ssif_start_processing(void *send_info,
struct ipmi_smi *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.");
static bool alerts_broken;
module_param(alerts_broken, bool, 0);
MODULE_PARM_DESC(alerts_broken, "Don't enable alerts 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 bool ssif_tryacpi = true;
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 = true;
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);
#define IPMI_SSIF_ATTR(name) \
static ssize_t ipmi_##name##_show(struct device *dev, \
struct device_attribute *attr, \
char *buf) \
{ \
struct ssif_info *ssif_info = dev_get_drvdata(dev); \
\
return snprintf(buf, 10, "%u\n", ssif_get_stat(ssif_info, name));\
} \
static DEVICE_ATTR(name, S_IRUGO, ipmi_##name##_show, NULL)
static ssize_t ipmi_type_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
return snprintf(buf, 10, "ssif\n");
}
static DEVICE_ATTR(type, S_IRUGO, ipmi_type_show, NULL);
IPMI_SSIF_ATTR(sent_messages);
IPMI_SSIF_ATTR(sent_messages_parts);
IPMI_SSIF_ATTR(send_retries);
IPMI_SSIF_ATTR(send_errors);
IPMI_SSIF_ATTR(received_messages);
IPMI_SSIF_ATTR(received_message_parts);
IPMI_SSIF_ATTR(receive_retries);
IPMI_SSIF_ATTR(receive_errors);
IPMI_SSIF_ATTR(flag_fetches);
IPMI_SSIF_ATTR(hosed);
IPMI_SSIF_ATTR(events);
IPMI_SSIF_ATTR(watchdog_pretimeouts);
IPMI_SSIF_ATTR(alerts);
static struct attribute *ipmi_ssif_dev_attrs[] = {
&dev_attr_type.attr,
&dev_attr_sent_messages.attr,
&dev_attr_sent_messages_parts.attr,
&dev_attr_send_retries.attr,
&dev_attr_send_errors.attr,
&dev_attr_received_messages.attr,
&dev_attr_received_message_parts.attr,
&dev_attr_receive_retries.attr,
&dev_attr_receive_errors.attr,
&dev_attr_flag_fetches.attr,
&dev_attr_hosed.attr,
&dev_attr_events.attr,
&dev_attr_watchdog_pretimeouts.attr,
&dev_attr_alerts.attr,
NULL
};
static const struct attribute_group ipmi_ssif_dev_attr_group = {
.attrs = ipmi_ssif_dev_attrs,
};
static void shutdown_ssif(void *send_info)
{
struct ssif_info *ssif_info = send_info;
device_remove_group(&ssif_info->client->dev, &ipmi_ssif_dev_attr_group);
dev_set_drvdata(&ssif_info->client->dev, 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);
}
}
static int ssif_remove(struct i2c_client *client)
{
struct ssif_info *ssif_info = i2c_get_clientdata(client);
struct ssif_addr_info *addr_info;
if (!ssif_info)
return 0;
/*
* After this point, we won't deliver anything asychronously
* to the message handler. We can unregister ourself.
*/
ipmi_unregister_smi(ssif_info->intf);
list_for_each_entry(addr_info, &ssif_infos, link) {
if (addr_info->client == client) {
addr_info->client = NULL;
break;
}
}
kfree(ssif_info);
return 0;
}
static int read_response(struct i2c_client *client, unsigned char *resp)
{
int 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;
}
return ret;
}
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 = read_response(client, resp);
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 if (ret > IPMI_MAX_MSG_LENGTH) {
ret = -E2BIG;
} 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 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;
}
static int find_slave_address(struct i2c_client *client, int slave_addr)
{
#ifdef CONFIG_IPMI_DMI_DECODE
if (!slave_addr)
slave_addr = ipmi_dmi_get_slave_addr(
SI_TYPE_INVALID,
i2c_adapter_id(client->adapter),
client->addr);
#endif
return slave_addr;
}
static int start_multipart_test(struct i2c_client *client,
unsigned char *msg, bool do_middle)
{
int retry_cnt = SSIF_SEND_RETRIES, ret;
retry_write:
ret = i2c_smbus_write_block_data(client,
SSIF_IPMI_MULTI_PART_REQUEST_START,
32, msg);
if (ret) {
retry_cnt--;
if (retry_cnt > 0)
goto retry_write;
dev_err(&client->dev, "Could not write multi-part start, though the BMC said it could handle it. Just limit sends to one part.\n");
return ret;
}
if (!do_middle)
return 0;
ret = i2c_smbus_write_block_data(client,
SSIF_IPMI_MULTI_PART_REQUEST_MIDDLE,
32, msg + 32);
if (ret) {
dev_err(&client->dev, "Could not write multi-part middle, though the BMC said it could handle it. Just limit sends to one part.\n");
return ret;
}
return 0;
}
static void test_multipart_messages(struct i2c_client *client,
struct ssif_info *ssif_info,
unsigned char *resp)
{
unsigned char msg[65];
int ret;
bool do_middle;
if (ssif_info->max_xmit_msg_size <= 32)
return;
do_middle = ssif_info->max_xmit_msg_size > 63;
memset(msg, 0, sizeof(msg));
msg[0] = IPMI_NETFN_APP_REQUEST << 2;
msg[1] = IPMI_GET_DEVICE_ID_CMD;
/*
* The specification is all messed up dealing with sending
* multi-part messages. Per what the specification says, it
* is impossible to send a message that is a multiple of 32
* bytes, except for 32 itself. It talks about a "start"
* transaction (cmd=6) that must be 32 bytes, "middle"
* transaction (cmd=7) that must be 32 bytes, and an "end"
* transaction. The "end" transaction is shown as cmd=7 in
* the text, but if that's the case there is no way to
* differentiate between a middle and end part except the
* length being less than 32. But there is a table at the far
* end of the section (that I had never noticed until someone
* pointed it out to me) that mentions it as cmd=8.
*
* After some thought, I think the example is wrong and the
* end transaction should be cmd=8. But some systems don't
* implement cmd=8, they use a zero-length end transaction,
* even though that violates the SMBus specification.
*
* So, to work around this, this code tests if cmd=8 works.
* If it does, then we use that. If not, it tests zero-
* byte end transactions. If that works, good. If not,
* we only allow 63-byte transactions max.
*/
ret = start_multipart_test(client, msg, do_middle);
if (ret)
goto out_no_multi_part;
ret = i2c_smbus_write_block_data(client,
SSIF_IPMI_MULTI_PART_REQUEST_END,
1, msg + 64);
if (!ret)
ret = read_response(client, resp);
if (ret > 0) {
/* End transactions work, we are good. */
ssif_info->cmd8_works = true;
return;
}
ret = start_multipart_test(client, msg, do_middle);
if (ret) {
dev_err(&client->dev, "Second multipart test failed.\n");
goto out_no_multi_part;
}
ret = i2c_smbus_write_block_data(client,
SSIF_IPMI_MULTI_PART_REQUEST_MIDDLE,
0, msg + 64);
if (!ret)
ret = read_response(client, resp);
if (ret > 0)
/* Zero-size end parts work, use those. */
return;
/* Limit to 63 bytes and use a short middle command to mark the end. */
if (ssif_info->max_xmit_msg_size > 63)
ssif_info->max_xmit_msg_size = 63;
return;
out_no_multi_part:
ssif_info->max_xmit_msg_size = 32;
return;
}
/*
* 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;
addr_info->client = client;
slave_addr = addr_info->slave_addr;
}
}
slave_addr = find_slave_address(client, slave_addr);
pr_info("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);
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("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:
/* We take whatever size given, but do some testing. */
break;
default:
/* Data is not sane, just give up. */
goto no_support;
}
} else {
no_support:
/* Assume no multi-part or PEC support */
pr_info("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;
}
test_multipart_messages(client, ssif_info, resp);
/* 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("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("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("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;
}
/* Some systems don't behave well if you enable alerts. */
if (alerts_broken)
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_RCV_MSG_INTR;
rv = do_cmd(client, 3, msg, &len, resp);
if (rv || (len < 2)) {
pr_warn("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:
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;
timer_setup(&ssif_info->retry_timer, retry_timeout, 0);
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.shutdown = shutdown_ssif;
ssif_info->handlers.get_smi_info = get_smi_info;
ssif_info->handlers.sender = sender;
ssif_info->handlers.request_events = request_events;
{
unsigned int thread_num;
thread_num = ((i2c_adapter_id(ssif_info->client->adapter)
<< 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;
}
}
dev_set_drvdata(&ssif_info->client->dev, ssif_info);
rv = device_add_group(&ssif_info->client->dev,
&ipmi_ssif_dev_attr_group);
if (rv) {
dev_err(&ssif_info->client->dev,
"Unable to add device attributes: error %d\n",
rv);
goto out;
}
rv = ipmi_register_smi(&ssif_info->handlers,
ssif_info,
&ssif_info->client->dev,
slave_addr);
if (rv) {
pr_err("Unable to register device: error %d\n", rv);
goto out_remove_attr;
}
out:
if (rv) {
if (addr_info)
addr_info->client = NULL;
dev_err(&client->dev, "Unable to start IPMI SSIF: %d\n", rv);
kfree(ssif_info);
}
kfree(resp);
return rv;
out_remove_attr:
device_remove_group(&ssif_info->client->dev, &ipmi_ssif_dev_attr_group);
dev_set_drvdata(&ssif_info->client->dev, NULL);
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;
addr_info->added_client = 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 device *dev)
{
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;
addr_info->dev = dev;
if (dev)
dev_set_drvdata(dev, addr_info);
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 = 0;
unsigned short *address_list;
list_for_each_entry(info, &ssif_infos, link)
count++;
address_list = kcalloc(count + 1, sizeof(*address_list),
GFP_KERNEL);
if (!address_list)
return NULL;
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)
/* Found a dup. */
break;
}
if (j == i) /* Didn't find it in the list. */
address_list[i++] = addr;
}
address_list[i] = I2C_CLIENT_END;
return address_list;
}
#ifdef CONFIG_ACPI
static const struct acpi_device_id ssif_acpi_match[] = {
{ "IPI0001", 0 },
{ },
};
MODULE_DEVICE_TABLE(acpi, ssif_acpi_match);
#endif
#ifdef CONFIG_DMI
static int dmi_ipmi_probe(struct platform_device *pdev)
{
u8 slave_addr = 0;
u16 i2c_addr;
int rv;
if (!ssif_trydmi)
return -ENODEV;
rv = device_property_read_u16(&pdev->dev, "i2c-addr", &i2c_addr);
if (rv) {
dev_warn(&pdev->dev, "No i2c-addr property\n");
return -ENODEV;
}
rv = device_property_read_u8(&pdev->dev, "slave-addr", &slave_addr);
if (rv)
dev_warn(&pdev->dev, "device has no slave-addr property");
return new_ssif_client(i2c_addr, NULL, 0,
slave_addr, SI_SMBIOS, &pdev->dev);
}
#else
static int dmi_ipmi_probe(struct platform_device *pdev)
{
return -ENODEV;
}
#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 = {
.name = DEVICE_NAME
},
.probe = ssif_probe,
.remove = ssif_remove,
.alert = ssif_alert,
.id_table = ssif_id,
.detect = ssif_detect
};
static int ssif_platform_probe(struct platform_device *dev)
{
return dmi_ipmi_probe(dev);
}
static int ssif_platform_remove(struct platform_device *dev)
{
struct ssif_addr_info *addr_info = dev_get_drvdata(&dev->dev);
if (!addr_info)
return 0;
mutex_lock(&ssif_infos_mutex);
i2c_unregister_device(addr_info->added_client);
list_del(&addr_info->link);
kfree(addr_info);
mutex_unlock(&ssif_infos_mutex);
return 0;
}
static const struct platform_device_id ssif_plat_ids[] = {
{ "dmi-ipmi-ssif", 0 },
{ }
};
static struct platform_driver ipmi_driver = {
.driver = {
.name = DEVICE_NAME,
},
.probe = ssif_platform_probe,
.remove = ssif_platform_remove,
.id_table = ssif_plat_ids
};
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, NULL);
if (rv)
pr_err("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) {
rv = platform_driver_register(&ipmi_driver);
if (rv)
pr_err("Unable to register driver: %d\n", rv);
}
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);
kfree(ssif_i2c_driver.address_list);
platform_driver_unregister(&ipmi_driver);
free_ssif_clients();
}
module_exit(cleanup_ipmi_ssif);
MODULE_ALIAS("platform:dmi-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");
