[SCSI] aacraid: add optional MSI support

Added support for MSI utilizing the aacraid.msi=1 parameter. This
patch adds some localized or like-minded janitor fixes. Since the
default is disabled, there is no impact on the code paths unless the
customer wishes to experiment with the MSI performance.

Signed-off-by: Mark Salyzyn <aacraid@adaptec.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
diff --git a/drivers/scsi/aacraid/aachba.c b/drivers/scsi/aacraid/aachba.c
index bfd0e64..f8d2ae3 100644
--- a/drivers/scsi/aacraid/aachba.c
+++ b/drivers/scsi/aacraid/aachba.c
@@ -144,51 +144,77 @@
  */
 
 static int nondasd = -1;
-static int aac_cache = 0;
+static int aac_cache;
 static int dacmode = -1;
-
+int aac_msi;
 int aac_commit = -1;
 int startup_timeout = 180;
 int aif_timeout = 120;
 
 module_param(nondasd, int, S_IRUGO|S_IWUSR);
-MODULE_PARM_DESC(nondasd, "Control scanning of hba for nondasd devices. 0=off, 1=on");
+MODULE_PARM_DESC(nondasd, "Control scanning of hba for nondasd devices."
+	" 0=off, 1=on");
 module_param_named(cache, aac_cache, int, S_IRUGO|S_IWUSR);
-MODULE_PARM_DESC(cache, "Disable Queue Flush commands:\n\tbit 0 - Disable FUA in WRITE SCSI commands\n\tbit 1 - Disable SYNCHRONIZE_CACHE SCSI command\n\tbit 2 - Disable only if Battery not protecting Cache");
+MODULE_PARM_DESC(cache, "Disable Queue Flush commands:\n"
+	"\tbit 0 - Disable FUA in WRITE SCSI commands\n"
+	"\tbit 1 - Disable SYNCHRONIZE_CACHE SCSI command\n"
+	"\tbit 2 - Disable only if Battery not protecting Cache");
 module_param(dacmode, int, S_IRUGO|S_IWUSR);
-MODULE_PARM_DESC(dacmode, "Control whether dma addressing is using 64 bit DAC. 0=off, 1=on");
+MODULE_PARM_DESC(dacmode, "Control whether dma addressing is using 64 bit DAC."
+	" 0=off, 1=on");
 module_param_named(commit, aac_commit, int, S_IRUGO|S_IWUSR);
-MODULE_PARM_DESC(commit, "Control whether a COMMIT_CONFIG is issued to the adapter for foreign arrays.\nThis is typically needed in systems that do not have a BIOS. 0=off, 1=on");
+MODULE_PARM_DESC(commit, "Control whether a COMMIT_CONFIG is issued to the"
+	" adapter for foreign arrays.\n"
+	"This is typically needed in systems that do not have a BIOS."
+	" 0=off, 1=on");
+module_param_named(msi, aac_msi, int, S_IRUGO|S_IWUSR);
+MODULE_PARM_DESC(msi, "IRQ handling."
+	" 0=PIC(default), 1=MSI, 2=MSI-X(unsupported, uses MSI)");
 module_param(startup_timeout, int, S_IRUGO|S_IWUSR);
-MODULE_PARM_DESC(startup_timeout, "The duration of time in seconds to wait for adapter to have it's kernel up and\nrunning. This is typically adjusted for large systems that do not have a BIOS.");
+MODULE_PARM_DESC(startup_timeout, "The duration of time in seconds to wait for"
+	" adapter to have it's kernel up and\n"
+	"running. This is typically adjusted for large systems that do not"
+	" have a BIOS.");
 module_param(aif_timeout, int, S_IRUGO|S_IWUSR);
-MODULE_PARM_DESC(aif_timeout, "The duration of time in seconds to wait for applications to pick up AIFs before\nderegistering them. This is typically adjusted for heavily burdened systems.");
+MODULE_PARM_DESC(aif_timeout, "The duration of time in seconds to wait for"
+	" applications to pick up AIFs before\n"
+	"deregistering them. This is typically adjusted for heavily burdened"
+	" systems.");
 
 int numacb = -1;
 module_param(numacb, int, S_IRUGO|S_IWUSR);
-MODULE_PARM_DESC(numacb, "Request a limit to the number of adapter control blocks (FIB) allocated. Valid values are 512 and down. Default is to use suggestion from Firmware.");
+MODULE_PARM_DESC(numacb, "Request a limit to the number of adapter control"
+	" blocks (FIB) allocated. Valid values are 512 and down. Default is"
+	" to use suggestion from Firmware.");
 
 int acbsize = -1;
 module_param(acbsize, int, S_IRUGO|S_IWUSR);
-MODULE_PARM_DESC(acbsize, "Request a specific adapter control block (FIB) size. Valid values are 512, 2048, 4096 and 8192. Default is to use suggestion from Firmware.");
+MODULE_PARM_DESC(acbsize, "Request a specific adapter control block (FIB)"
+	" size. Valid values are 512, 2048, 4096 and 8192. Default is to use"
+	" suggestion from Firmware.");
 
 int update_interval = 30 * 60;
 module_param(update_interval, int, S_IRUGO|S_IWUSR);
-MODULE_PARM_DESC(update_interval, "Interval in seconds between time sync updates issued to adapter.");
+MODULE_PARM_DESC(update_interval, "Interval in seconds between time sync"
+	" updates issued to adapter.");
 
 int check_interval = 24 * 60 * 60;
 module_param(check_interval, int, S_IRUGO|S_IWUSR);
-MODULE_PARM_DESC(check_interval, "Interval in seconds between adapter health checks.");
+MODULE_PARM_DESC(check_interval, "Interval in seconds between adapter health"
+	" checks.");
 
 int aac_check_reset = 1;
 module_param_named(check_reset, aac_check_reset, int, S_IRUGO|S_IWUSR);
-MODULE_PARM_DESC(aac_check_reset, "If adapter fails health check, reset the adapter. a value of -1 forces the reset to adapters programmed to ignore it.");
+MODULE_PARM_DESC(aac_check_reset, "If adapter fails health check, reset the"
+	" adapter. a value of -1 forces the reset to adapters programmed to"
+	" ignore it.");
 
 int expose_physicals = -1;
 module_param(expose_physicals, int, S_IRUGO|S_IWUSR);
-MODULE_PARM_DESC(expose_physicals, "Expose physical components of the arrays. -1=protect 0=off, 1=on");
+MODULE_PARM_DESC(expose_physicals, "Expose physical components of the arrays."
+	" -1=protect 0=off, 1=on");
 
-int aac_reset_devices = 0;
+int aac_reset_devices;
 module_param_named(reset_devices, aac_reset_devices, int, S_IRUGO|S_IWUSR);
 MODULE_PARM_DESC(reset_devices, "Force an adapter reset at initialization.");