[SCSI] implement parameter limits in the SPI transport class

There's a basic need not to have parameters go under or over certain
values when doing domain validation.  The basic ones are

max_offset, max_width and min_period

This patch makes the transport class take and enforce these three
limits.  Currently they can be set by the user, although they could
obviously be read from the HBA's on-board NVRAM area during
slave_configure (if it has one).

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/include/scsi/scsi_transport_spi.h b/include/scsi/scsi_transport_spi.h
index 6dcf497bf46d..a30d6cd4c0e8 100644
--- a/include/scsi/scsi_transport_spi.h
+++ b/include/scsi/scsi_transport_spi.h
@@ -27,8 +27,11 @@ struct scsi_transport_template;
 
 struct spi_transport_attrs {
         int period;             /* value in the PPR/SDTR command */
+        int min_period;
         int offset;
+        int max_offset;
         unsigned int width:1;   /* 0 - narrow, 1 - wide */
+        unsigned int max_width:1;
         unsigned int iu:1;      /* Information Units enabled */
         unsigned int dt:1;      /* DT clocking enabled */
         unsigned int qas:1;     /* Quick Arbitration and Selection enabled */
@@ -63,8 +66,11 @@ struct spi_host_attrs {
 
 /* accessor functions */
 #define spi_period(x)   (((struct spi_transport_attrs *)&(x)->starget_data)->period)
+#define spi_min_period(x) (((struct spi_transport_attrs *)&(x)->starget_data)->min_period)
 #define spi_offset(x)   (((struct spi_transport_attrs *)&(x)->starget_data)->offset)
+#define spi_max_offset(x) (((struct spi_transport_attrs *)&(x)->starget_data)->max_offset)
 #define spi_width(x)    (((struct spi_transport_attrs *)&(x)->starget_data)->width)
+#define spi_max_width(x) (((struct spi_transport_attrs *)&(x)->starget_data)->max_width)
 #define spi_iu(x)       (((struct spi_transport_attrs *)&(x)->starget_data)->iu)
 #define spi_dt(x)       (((struct spi_transport_attrs *)&(x)->starget_data)->dt)
 #define spi_qas(x)      (((struct spi_transport_attrs *)&(x)->starget_data)->qas)