[PATCH] Minor cleanups to the IPMI driver

This patch cleans up the DMI handling so that multiple interfaces can be
reported from the DMI tables and so that the DMI slave address can be
transferred up to the upper layer.  It also adds an option to specify the
slave address as an init parm and removes some unnecessary initializers.

This patch also adds inc/dec usecount functions for the SMIs so they can
modify the usecounts of modules they use (added because the SMB driver uses
the I2C code).
Signed-off-by: Corey Minyard <minyard@acm.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Documentation/IPMI.txt

@@ -342,6 +342,7 @@ You can change this at module load time (for a module) with:
        irqs=<irq1>,<irq2>... trydefaults=[0|1]
        regspacings=<sp1>,<sp2>,... regsizes=<size1>,<size2>,...
        regshifts=<shift1>,<shift2>,...
+       slave_addrs=<addr1>,<addr2>,...
 
 Each of these except si_trydefaults is a list, the first item for the
 first interface, second item for the second interface, etc.
@@ -383,6 +384,10 @@ Since the register size may be larger than 32 bits, the IPMI data may not
 be in the lower 8 bits.  The regshifts parameter give the amount to shift
 the data to get to the actual IPMI data.
 
+The slave_addrs specifies the IPMI address of the local BMC.  This is
+usually 0x20 and the driver defaults to that, but in case it's not, it
+can be specified when the driver starts up.
+
 When compiled into the kernel, the addresses can be specified on the
 kernel command line as:
 
@@ -392,6 +397,7 @@ kernel command line as:
        ipmi_si.regspacings=<sp1>,<sp2>,...
        ipmi_si.regsizes=<size1>,<size2>,...
        ipmi_si.regshifts=<shift1>,<shift2>,...
+       ipmi_si.slave_addrs=<addr1>,<addr2>,...
 
 It works the same as the module parameters of the same names.
 

drivers/char/ipmi/ipmi_msghandler.c

@@ -612,6 +612,7 @@ int ipmi_create_user(unsigned int          if_num,
 	unsigned long flags;
 	ipmi_user_t   new_user;
 	int           rv = 0;
+	ipmi_smi_t    intf;
 
 	/* There is no module usecount here, because it's not
            required.  Since this can only be used by and called from
@@ -646,19 +647,29 @@ int ipmi_create_user(unsigned int          if_num,
 		goto out_unlock;
 	}
 
+	intf = ipmi_interfaces[if_num];
+
 	new_user->handler = handler;
 	new_user->handler_data = handler_data;
-	new_user->intf = ipmi_interfaces[if_num];
+	new_user->intf = intf;
 	new_user->gets_events = 0;
 
-	if (!try_module_get(new_user->intf->handlers->owner)) {
+	if (!try_module_get(intf->handlers->owner)) {
 		rv = -ENODEV;
 		goto out_unlock;
 	}
 
-	write_lock_irqsave(&new_user->intf->users_lock, flags);
-	list_add_tail(&new_user->link, &new_user->intf->users);
-	write_unlock_irqrestore(&new_user->intf->users_lock, flags);
+	if (intf->handlers->inc_usecount) {
+		rv = intf->handlers->inc_usecount(intf->send_info);
+		if (rv) {
+			module_put(intf->handlers->owner);
+			goto out_unlock;
+		}
+	}
+
+	write_lock_irqsave(&intf->users_lock, flags);
+	list_add_tail(&new_user->link, &intf->users);
+	write_unlock_irqrestore(&intf->users_lock, flags);
 
  out_unlock:	
 	if (rv) {
@@ -729,8 +740,11 @@ int ipmi_destroy_user(ipmi_user_t user)
 	down_read(&interfaces_sem);
 	write_lock_irqsave(&intf->users_lock, flags);
 	rv = ipmi_destroy_user_nolock(user);
-	if (!rv)
+	if (!rv) {
 		module_put(intf->handlers->owner);
+		if (intf->handlers->dec_usecount)
+			intf->handlers->dec_usecount(intf->send_info);
+	}
 		
 	write_unlock_irqrestore(&intf->users_lock, flags);
 	up_read(&interfaces_sem);
@@ -1629,6 +1643,7 @@ int ipmi_register_smi(struct ipmi_smi_handlers *handlers,
 		      void		       *send_info,
 		      unsigned char            version_major,
 		      unsigned char            version_minor,
+		      unsigned char            slave_addr,
 		      ipmi_smi_t               *intf)
 {
 	int              i, j;
@@ -1664,7 +1679,10 @@ int ipmi_register_smi(struct ipmi_smi_handlers *handlers,
 			new_intf->intf_num = i;
 			new_intf->version_major = version_major;
 			new_intf->version_minor = version_minor;
+			if (slave_addr == 0)
 				new_intf->my_address = IPMI_BMC_SLAVE_ADDR;
+			else
+				new_intf->my_address = slave_addr;
 			new_intf->my_lun = 2;  /* the SMS LUN. */
 			rwlock_init(&(new_intf->users_lock));
 			INIT_LIST_HEAD(&(new_intf->users));

drivers/char/ipmi/ipmi_si_intf.c

@@ -176,6 +176,9 @@ struct smi_info
 	unsigned char ipmi_version_major;
 	unsigned char ipmi_version_minor;
 
+	/* Slave address, could be reported from DMI. */
+	unsigned char slave_addr;
+
 	/* Counters and things for the proc filesystem. */
 	spinlock_t count_lock;
 	unsigned long short_timeouts;
@@ -407,7 +410,7 @@ static void handle_transaction_done(struct smi_info *smi_info)
 			/* Error fetching flags, just give up for
 			   now. */
 			smi_info->si_state = SI_NORMAL;
-		} else if (len < 3) {
+		} else if (len < 4) {
 			/* Hmm, no flags.  That's technically illegal, but
 			   don't use uninitialized data. */
 			smi_info->si_state = SI_NORMAL;
@@ -897,21 +900,23 @@ static struct smi_info *smi_infos[SI_MAX_DRIVERS] =
 #define DEFAULT_REGSPACING	1
 
 static int           si_trydefaults = 1;
-static char          *si_type[SI_MAX_PARMS] = { NULL, NULL, NULL, NULL };
+static char          *si_type[SI_MAX_PARMS];
 #define MAX_SI_TYPE_STR 30
 static char          si_type_str[MAX_SI_TYPE_STR];
-static unsigned long addrs[SI_MAX_PARMS] = { 0, 0, 0, 0 };
-static int num_addrs = 0;
-static unsigned int  ports[SI_MAX_PARMS] = { 0, 0, 0, 0 };
-static int num_ports = 0;
-static int           irqs[SI_MAX_PARMS] = { 0, 0, 0, 0 };
-static int num_irqs = 0;
-static int           regspacings[SI_MAX_PARMS] = { 0, 0, 0, 0 };
+static unsigned long addrs[SI_MAX_PARMS];
+static int num_addrs;
+static unsigned int  ports[SI_MAX_PARMS];
+static int num_ports;
+static int           irqs[SI_MAX_PARMS];
+static int num_irqs;
+static int           regspacings[SI_MAX_PARMS];
 static int num_regspacings = 0;
-static int           regsizes[SI_MAX_PARMS] = { 0, 0, 0, 0 };
+static int           regsizes[SI_MAX_PARMS];
 static int num_regsizes = 0;
-static int           regshifts[SI_MAX_PARMS] = { 0, 0, 0, 0 };
+static int           regshifts[SI_MAX_PARMS];
 static int num_regshifts = 0;
+static int slave_addrs[SI_MAX_PARMS];
+static int num_slave_addrs = 0;
 
 
 module_param_named(trydefaults, si_trydefaults, bool, 0);
@@ -955,6 +960,12 @@ MODULE_PARM_DESC(regshifts, "The amount to shift the data read from the."
 		 " IPMI register, in bits.  For instance, if the data"
 		 " is read from a 32-bit word and the IPMI data is in"
 		 " bit 8-15, then the shift would be 8");
+module_param_array(slave_addrs, int, &num_slave_addrs, 0);
+MODULE_PARM_DESC(slave_addrs, "Set the default IPMB slave address for"
+		 " the controller.  Normally this is 0x20, but can be"
+		 " overridden by this parm.  This is an array indexed"
+		 " by interface number.");
+
 
 #define IPMI_MEM_ADDR_SPACE 1
 #define IPMI_IO_ADDR_SPACE  2
@@ -1542,7 +1553,6 @@ static int try_init_acpi(int intf_num, struct smi_info **new_info)
 #endif
 
 #ifdef CONFIG_X86
-
 typedef struct dmi_ipmi_data
 {
 	u8   		type;
@@ -1550,21 +1560,26 @@ typedef struct dmi_ipmi_data
 	unsigned long	base_addr;
 	u8   		irq;
 	u8              offset;
-}dmi_ipmi_data_t;
+	u8              slave_addr;
+} dmi_ipmi_data_t;
+
+static dmi_ipmi_data_t dmi_data[SI_MAX_DRIVERS];
+static int dmi_data_entries;
 
 typedef struct dmi_header
 {
 	u8	type;
 	u8	length;
 	u16	handle;
-}dmi_header_t;
+} dmi_header_t;
 
-static int decode_dmi(dmi_header_t *dm, dmi_ipmi_data_t *ipmi_data)
+static int decode_dmi(dmi_header_t *dm, int intf_num)
 {
 	u8		*data = (u8 *)dm;
 	unsigned long  	base_addr;
 	u8		reg_spacing;
 	u8              len = dm->length;
+	dmi_ipmi_data_t *ipmi_data = dmi_data+intf_num;
 
 	ipmi_data->type = data[4];
 
@@ -1608,22 +1623,26 @@ static int decode_dmi(dmi_header_t *dm, dmi_ipmi_data_t *ipmi_data)
 		ipmi_data->offset = 1;
 	}
 
-	if (is_new_interface(-1, ipmi_data->addr_space,ipmi_data->base_addr))
+	ipmi_data->slave_addr = data[6];
+
+	if (is_new_interface(-1, ipmi_data->addr_space,ipmi_data->base_addr)) {
+		dmi_data_entries++;
 		return 0;
+	}
 
 	memset(ipmi_data, 0, sizeof(dmi_ipmi_data_t));
 
 	return -1;
 }
 
-static int dmi_table(u32 base, int len, int num,
-	dmi_ipmi_data_t *ipmi_data)
+static int dmi_table(u32 base, int len, int num)
 {
 	u8 		  *buf;
 	struct dmi_header *dm;
 	u8 		  *data;
 	int 		  i=1;
 	int		  status=-1;
+	int               intf_num = 0;
 
 	buf = ioremap(base, len);
 	if(buf==NULL)
@@ -1639,8 +1658,9 @@ static int dmi_table(u32 base, int len, int num,
         		break;
 
 		if (dm->type == 38) {
-			if (decode_dmi(dm, ipmi_data) == 0) {
-				status = 0;
+			if (decode_dmi(dm, intf_num) == 0) {
+				intf_num++;
+				if (intf_num >= SI_MAX_DRIVERS)
 					break;
 			}
 		}
@@ -1666,7 +1686,7 @@ inline static int dmi_checksum(u8 *buf)
 	return (sum==0);
 }
 
-static int dmi_iterator(dmi_ipmi_data_t *ipmi_data)
+static int dmi_decode(void)
 {
 	u8   buf[15];
 	u32  fp=0xF0000;
@@ -1684,7 +1704,7 @@ static int dmi_iterator(dmi_ipmi_data_t *ipmi_data)
 			u16 len=buf[7]<<8|buf[6];
 			u32 base=buf[11]<<24|buf[10]<<16|buf[9]<<8|buf[8];
 
-			if(dmi_table(base, len, num, ipmi_data) == 0)
+			if(dmi_table(base, len, num) == 0)
 				return 0;
 		}
 		fp+=16;
@@ -1696,16 +1716,13 @@ static int dmi_iterator(dmi_ipmi_data_t *ipmi_data)
 static int try_init_smbios(int intf_num, struct smi_info **new_info)
 {
 	struct smi_info   *info;
-	dmi_ipmi_data_t   ipmi_data;
+	dmi_ipmi_data_t   *ipmi_data = dmi_data+intf_num;
 	char              *io_type;
-	int               status;
 
-	status = dmi_iterator(&ipmi_data);
-
-	if (status < 0)
+	if (intf_num >= dmi_data_entries)
 		return -ENODEV;
 
-	switch(ipmi_data.type) {
+	switch(ipmi_data->type) {
 		case 0x01: /* KCS */
 			si_type[intf_num] = "kcs";
 			break;
@@ -1716,7 +1733,6 @@ static int try_init_smbios(int intf_num, struct smi_info **new_info)
 			si_type[intf_num] = "bt";
 			break;
 		default:
-			printk("ipmi_si: Unknown SMBIOS SI type.\n");
 			return -EIO;
 	}
 
@@ -1727,15 +1743,15 @@ static int try_init_smbios(int intf_num, struct smi_info **new_info)
 	}
 	memset(info, 0, sizeof(*info));
 
-	if (ipmi_data.addr_space == 1) {
+	if (ipmi_data->addr_space == 1) {
 		io_type = "memory";
 		info->io_setup = mem_setup;
-		addrs[intf_num] = ipmi_data.base_addr;
+		addrs[intf_num] = ipmi_data->base_addr;
 		info->io.info = &(addrs[intf_num]);
-	} else if (ipmi_data.addr_space == 2) {
+	} else if (ipmi_data->addr_space == 2) {
 		io_type = "I/O";
 		info->io_setup = port_setup;
-		ports[intf_num] = ipmi_data.base_addr;
+		ports[intf_num] = ipmi_data->base_addr;
 		info->io.info = &(ports[intf_num]);
 	} else {
 		kfree(info);
@@ -1743,20 +1759,23 @@ static int try_init_smbios(int intf_num, struct smi_info **new_info)
 		return -EIO;
 	}
 
-	regspacings[intf_num] = ipmi_data.offset;
+	regspacings[intf_num] = ipmi_data->offset;
 	info->io.regspacing = regspacings[intf_num];
 	if (!info->io.regspacing)
 		info->io.regspacing = DEFAULT_REGSPACING;
 	info->io.regsize = DEFAULT_REGSPACING;
 	info->io.regshift = regshifts[intf_num];
 
-	irqs[intf_num] = ipmi_data.irq;
+	info->slave_addr = ipmi_data->slave_addr;
+
+	irqs[intf_num] = ipmi_data->irq;
 
 	*new_info = info;
 
 	printk("ipmi_si: Found SMBIOS-specified state machine at %s"
-	       " address 0x%lx\n",
-	       io_type, (unsigned long)ipmi_data.base_addr);
+	       " address 0x%lx, slave address 0x%x\n",
+	       io_type, (unsigned long)ipmi_data->base_addr,
+	       ipmi_data->slave_addr);
 	return 0;
 }
 #endif /* CONFIG_X86 */
@@ -2121,6 +2140,7 @@ static int init_one_smi(int intf_num, struct smi_info **smi)
 			       new_smi,
 			       new_smi->ipmi_version_major,
 			       new_smi->ipmi_version_minor,
+			       new_smi->slave_addr,
 			       &(new_smi->intf));
 	if (rv) {
 		printk(KERN_ERR
@@ -2222,6 +2242,10 @@ static __init int init_ipmi_si(void)
    	        printk(", BT version %s", bt_smi_handlers.version);
 	printk("\n");
 
+#ifdef CONFIG_X86
+	dmi_decode();
+#endif
+
 	rv = init_one_smi(0, &(smi_infos[pos]));
 	if (rv && !ports[0] && si_trydefaults) {
 		/* If we are trying defaults and the initial port is

include/linux/ipmi_smi.h

@@ -104,13 +104,22 @@ struct ipmi_smi_handlers
 	/* Called to poll for work to do.  This is so upper layers can
 	   poll for operations during things like crash dumps. */
 	void (*poll)(void *send_info);
+
+	/* Tell the handler that we are using it/not using it.  The
+	   message handler get the modules that this handler belongs
+	   to; this function lets the SMI claim any modules that it
+	   uses.  These may be NULL if this is not required. */
+	int (*inc_usecount)(void *send_info);
+	void (*dec_usecount)(void *send_info);
 };
 
-/* Add a low-level interface to the IPMI driver. */
+/* Add a low-level interface to the IPMI driver.  Note that if the
+   interface doesn't know its slave address, it should pass in zero. */
 int ipmi_register_smi(struct ipmi_smi_handlers *handlers,
 		      void                     *send_info,
 		      unsigned char            version_major,
 		      unsigned char            version_minor,
+		      unsigned char            slave_addr,
 		      ipmi_smi_t               *intf);
 
 /*