ide: Refactor confusing loop code

This code is hard to follow as it uses #ifdef in a strange way. Adjust
it to avoid the preprocessor. Drop the special return for the non-ATAPI
case since we can rely on tries becoming 0 and exiting the loop.

Signed-off-by: Simon Glass <sjg@chromium.org>

diff --git a/drivers/block/ide.c b/drivers/block/ide.c
index 782780f..2f45bb6 100644 (file)
--- a/drivers/block/ide.c
+++ b/drivers/block/ide.c
@@ -555,10 +555,8 @@ static void ide_ident(struct blk_desc *dev_desc)
 {
        unsigned char c;
        hd_driveid_t iop;
-#ifdef CONFIG_ATAPI
        bool is_atapi = false;
        int tries = 1;
-#endif
        int device;
 
        device = dev_desc->devnum;
@@ -568,17 +566,16 @@ static void ide_ident(struct blk_desc *dev_desc)
         */
        ide_outb(device, ATA_DEV_HD, ATA_LBA | ATA_DEVICE(device));
        dev_desc->uclass_id = UCLASS_IDE;
-#ifdef CONFIG_ATAPI
+       if (IS_ENABLED(CONFIG_ATAPI))
+               tries = 2;
 
-       tries = 2;
-
-       /* Warning: This will be tricky to read */
        while (tries) {
                /* check signature */
-               if ((ide_inb(device, ATA_SECT_CNT) == 0x01) &&
-                   (ide_inb(device, ATA_SECT_NUM) == 0x01) &&
-                   (ide_inb(device, ATA_CYL_LOW) == 0x14) &&
-                   (ide_inb(device, ATA_CYL_HIGH) == 0xEB)) {
+               if (IS_ENABLED(CONFIG_ATAPI) &&
+                   ide_inb(device, ATA_SECT_CNT) == 0x01 &&
+                   ide_inb(device, ATA_SECT_NUM) == 0x01 &&
+                   ide_inb(device, ATA_CYL_LOW) == 0x14 &&
+                   ide_inb(device, ATA_CYL_HIGH) == 0xeb) {
                        /* ATAPI Signature found */
                        is_atapi = true;
                        /*
@@ -590,9 +587,7 @@ static void ide_ident(struct blk_desc *dev_desc)
                         * to become ready
                         */
                        c = ide_wait(device, ATAPI_TIME_OUT);
-               } else
-#endif
-               {
+               } else {
                        /*
                         * Start Ident Command
                         */
@@ -606,8 +601,7 @@ static void ide_ident(struct blk_desc *dev_desc)
 
                if (((c & ATA_STAT_DRQ) == 0) ||
                    ((c & (ATA_STAT_FAULT | ATA_STAT_ERR)) != 0)) {
-#ifdef CONFIG_ATAPI
-                       {
+                       if (IS_ENABLED(CONFIG_ATAPI)) {
                                /*
                                 * Need to soft reset the device
                                 * in case it's an ATAPI...
@@ -618,25 +612,18 @@ static void ide_ident(struct blk_desc *dev_desc)
                                mdelay(100);
                                ide_outb(device, ATA_COMMAND, 0x08);
                                mdelay(500);
+                               /* Select device */
+                               ide_outb(device, ATA_DEV_HD,
+                                        ATA_LBA | ATA_DEVICE(device));
                        }
-                       /*
-                        * Select device
-                        */
-                       ide_outb(device, ATA_DEV_HD,
-                                ATA_LBA | ATA_DEVICE(device));
                        tries--;
-#else
-                       return;
-#endif
-               }
-#ifdef CONFIG_ATAPI
-               else
+               } else {
                        break;
-       }                       /* see above - ugly to read */
+               }
+       }
 
        if (!tries)     /* Not found */
                return;
-#endif
 
        ide_input_swap_data(device, (ulong *)&iop, ATA_SECTORWORDS);