m68k/scsi: gvp11 - Extract check_wd33c93()

Acked-by: James Bottomley <James.Bottomley@suse.de>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

1 files changed, 83 insertions, 77 deletions

diff --git a/drivers/scsi/gvp11.c b/drivers/scsi/gvp11.c
index 777972e6bbf3..59a7bff53e13 100644
--- a/drivers/scsi/gvp11.c
+++ b/drivers/scsi/gvp11.c
@@ -22,6 +22,8 @@
 #include <linux/stat.h>
 
 
+#define CHECK_WD33C93
+
 static irqreturn_t gvp11_intr(int irq, void *data)
 {
         struct Scsi_Host *instance = data;
@@ -167,7 +169,85 @@ static void dma_stop(struct Scsi_Host *instance, struct scsi_cmnd *SCpnt,
         }
 }
 
-#define CHECK_WD33C93
+static int __init check_wd33c93(gvp11_scsiregs *regs)
+{
+#ifdef CHECK_WD33C93
+        volatile unsigned char *sasr_3393, *scmd_3393;
+        unsigned char save_sasr;
+        unsigned char q, qq;
+
+        /*
+         * These darn GVP boards are a problem - it can be tough to tell
+         * whether or not they include a SCSI controller. This is the
+         * ultimate Yet-Another-GVP-Detection-Hack in that it actually
+         * probes for a WD33c93 chip: If we find one, it's extremely
+         * likely that this card supports SCSI, regardless of Product_
+         * Code, Board_Size, etc.
+         */
+
+        /* Get pointers to the presumed register locations and save contents */
+
+        sasr_3393 = &regs->SASR;
+        scmd_3393 = &regs->SCMD;
+        save_sasr = *sasr_3393;
+
+        /* First test the AuxStatus Reg */
+
+        q = *sasr_3393; /* read it */
+        if (q & 0x08)   /* bit 3 should always be clear */
+                return -ENODEV;
+        *sasr_3393 = WD_AUXILIARY_STATUS;       /* setup indirect address */
+        if (*sasr_3393 == WD_AUXILIARY_STATUS) {        /* shouldn't retain the write */
+                *sasr_3393 = save_sasr; /* Oops - restore this byte */
+                return -ENODEV;
+        }
+        if (*sasr_3393 != q) {  /* should still read the same */
+                *sasr_3393 = save_sasr; /* Oops - restore this byte */
+                return -ENODEV;
+        }
+        if (*scmd_3393 != q)    /* and so should the image at 0x1f */
+                return -ENODEV;
+
+        /*
+         * Ok, we probably have a wd33c93, but let's check a few other places
+         * for good measure. Make sure that this works for both 'A and 'B
+         * chip versions.
+         */
+
+        *sasr_3393 = WD_SCSI_STATUS;
+        q = *scmd_3393;
+        *sasr_3393 = WD_SCSI_STATUS;
+        *scmd_3393 = ~q;
+        *sasr_3393 = WD_SCSI_STATUS;
+        qq = *scmd_3393;
+        *sasr_3393 = WD_SCSI_STATUS;
+        *scmd_3393 = q;
+        if (qq != q)    /* should be read only */
+                return -ENODEV;
+        *sasr_3393 = 0x1e;      /* this register is unimplemented */
+        q = *scmd_3393;
+        *sasr_3393 = 0x1e;
+        *scmd_3393 = ~q;
+        *sasr_3393 = 0x1e;
+        qq = *scmd_3393;
+        *sasr_3393 = 0x1e;
+        *scmd_3393 = q;
+        if (qq != q || qq != 0xff)      /* should be read only, all 1's */
+                return -ENODEV;
+        *sasr_3393 = WD_TIMEOUT_PERIOD;
+        q = *scmd_3393;
+        *sasr_3393 = WD_TIMEOUT_PERIOD;
+        *scmd_3393 = ~q;
+        *sasr_3393 = WD_TIMEOUT_PERIOD;
+        qq = *scmd_3393;
+        *sasr_3393 = WD_TIMEOUT_PERIOD;
+        *scmd_3393 = q;
+        if (qq != (~q & 0xff))  /* should be read/write */
+                return -ENODEV;
+#endif /* CHECK_WD33C93 */
+
+        return 0;
+}
 
 int __init gvp11_detect(struct scsi_host_template *tpnt)
 {
@@ -181,11 +261,6 @@ int __init gvp11_detect(struct scsi_host_template *tpnt)
         gvp11_scsiregs *regs;
         wd33c93_regs wdregs;
         int num_gvp11 = 0;
-#ifdef CHECK_WD33C93
-        volatile unsigned char *sasr_3393, *scmd_3393;
-        unsigned char save_sasr;
-        unsigned char q, qq;
-#endif
 
         if (!MACH_IS_AMIGA || called)
                 return 0;
@@ -226,77 +301,9 @@ int __init gvp11_detect(struct scsi_host_template *tpnt)
                 if (!request_mem_region(address, 256, "wd33c93"))
                         continue;
 
-#ifdef CHECK_WD33C93
-
-                /*
-                 * These darn GVP boards are a problem - it can be tough to tell
-                 * whether or not they include a SCSI controller. This is the
-                 * ultimate Yet-Another-GVP-Detection-Hack in that it actually
-                 * probes for a WD33c93 chip: If we find one, it's extremely
-                 * likely that this card supports SCSI, regardless of Product_
-                 * Code, Board_Size, etc.
-                 */
-
-                /* Get pointers to the presumed register locations and save contents */
-
-                sasr_3393 = &(((gvp11_scsiregs *)(ZTWO_VADDR(address)))->SASR);
-                scmd_3393 = &(((gvp11_scsiregs *)(ZTWO_VADDR(address)))->SCMD);
-                save_sasr = *sasr_3393;
-
-                /* First test the AuxStatus Reg */
-
-                q = *sasr_3393; /* read it */
-                if (q & 0x08)   /* bit 3 should always be clear */
-                        goto release;
-                *sasr_3393 = WD_AUXILIARY_STATUS;       /* setup indirect address */
-                if (*sasr_3393 == WD_AUXILIARY_STATUS) {        /* shouldn't retain the write */
-                        *sasr_3393 = save_sasr; /* Oops - restore this byte */
-                        goto release;
-                }
-                if (*sasr_3393 != q) {  /* should still read the same */
-                        *sasr_3393 = save_sasr; /* Oops - restore this byte */
-                        goto release;
-                }
-                if (*scmd_3393 != q)    /* and so should the image at 0x1f */
-                        goto release;
-
-                /*
-                 * Ok, we probably have a wd33c93, but let's check a few other places
-                 * for good measure. Make sure that this works for both 'A and 'B
-                 * chip versions.
-                 */
-
-                *sasr_3393 = WD_SCSI_STATUS;
-                q = *scmd_3393;
-                *sasr_3393 = WD_SCSI_STATUS;
-                *scmd_3393 = ~q;
-                *sasr_3393 = WD_SCSI_STATUS;
-                qq = *scmd_3393;
-                *sasr_3393 = WD_SCSI_STATUS;
-                *scmd_3393 = q;
-                if (qq != q)    /* should be read only */
-                        goto release;
-                *sasr_3393 = 0x1e;      /* this register is unimplemented */
-                q = *scmd_3393;
-                *sasr_3393 = 0x1e;
-                *scmd_3393 = ~q;
-                *sasr_3393 = 0x1e;
-                qq = *scmd_3393;
-                *sasr_3393 = 0x1e;
-                *scmd_3393 = q;
-                if (qq != q || qq != 0xff)      /* should be read only, all 1's */
+                regs = (gvp11_scsiregs *)(ZTWO_VADDR(address));
+                if (check_wd33c93(regs))
                         goto release;
-                *sasr_3393 = WD_TIMEOUT_PERIOD;
-                q = *scmd_3393;
-                *sasr_3393 = WD_TIMEOUT_PERIOD;
-                *scmd_3393 = ~q;
-                *sasr_3393 = WD_TIMEOUT_PERIOD;
-                qq = *scmd_3393;
-                *sasr_3393 = WD_TIMEOUT_PERIOD;
-                *scmd_3393 = q;
-                if (qq != (~q & 0xff))  /* should be read/write */
-                        goto release;
-#endif
 
                 instance = scsi_register(tpnt, sizeof(struct WD33C93_hostdata));
                 if (instance == NULL)
@@ -311,7 +318,6 @@ int __init gvp11_detect(struct scsi_host_template *tpnt)
                 else
                         hdata->dma_xfer_mask = default_dma_xfer_mask;
 
-                regs = (gvp11_scsiregs *)(instance->base);
                 regs->secret2 = 1;
                 regs->secret1 = 0;
                 regs->secret3 = 15;