diff options
Diffstat (limited to 'drivers/char/ipmi/ipmi_ssif.c')
| -rw-r--r-- | drivers/char/ipmi/ipmi_ssif.c | 1870 |
1 files changed, 1870 insertions, 0 deletions
diff --git a/drivers/char/ipmi/ipmi_ssif.c b/drivers/char/ipmi/ipmi_ssif.c new file mode 100644 index 000000000000..e178ac27e73c --- /dev/null +++ b/drivers/char/ipmi/ipmi_ssif.c @@ -0,0 +1,1870 @@ +/* + * 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. + */ + +#include <linux/version.h> +#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> + +#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, + + /* 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; + + bool has_event_buffer; + + /* + * 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 */ + wait_for_completion(&ssif_info->wake_thread); + init_completion(&ssif_info->wake_thread); + + if (ssif_info->stopping) + break; + + if (ssif_info->i2c_read_write == I2C_SMBUS_WRITE) { + result = i2c_smbus_write_block_data( + ssif_info->client, SSIF_IPMI_REQUEST, + 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_IPMI_RESPONSE, + 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 retry_timeout(unsigned long data) +{ + struct ssif_info *ssif_info = (void *) data; + int rv; + + if (ssif_info->stopping) + return; + + ssif_info->rtc_us_timer = 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 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); + + mod_timer(&ssif_info->retry_timer, + jiffies + SSIF_MSG_JIFFIES); + ssif_info->rtc_us_timer = SSIF_MSG_USEC; + 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. */ + for (i = 0; i < (len-2); i++) + ssif_info->data[i] = data[i+2]; + len -= 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[ssif_info->multi_len]; + + 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. */ + for (i = 0; i < (len-1); i++) + ssif_info->data[i+ssif_info->multi_len] = data[i+1]; + len--; + 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 i2c_non_blocking_op(2)\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. */ + 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 { + ssif_inc_stat(ssif_info, sent_messages); + ssif_inc_stat(ssif_info, sent_messages_parts); + + /* Wait a jiffie then request the next message */ + 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); + return; + } +} + +static int start_resend(struct ssif_info *ssif_info) +{ + int rv; + int command; + + 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], t.tv_sec, 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; + + i2c_set_clientdata(client, NULL); + + /* + * 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) +{ + return seq_puts(m, "ssif\n"); +} + +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)); + 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 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 (strcmp(info->adapter_name, adapter_name)) + /* Names to 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 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 > 64) + ssif_info->max_xmit_msg_size = 64; + if (ssif_info->max_recv_msg_size > 62) + ssif_info->max_recv_msg_size = 62; + break; + + case SSIF_MULTI_n_PART: + 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; + } + + 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] = resp[3] | IPMI_BMC_EVT_MSG_BUFF; + rv = do_cmd(client, 3, msg, &len, resp); + if (rv || (len < 2)) { + pr_warn(PFX "Error getting 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; + + 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, + .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"); |