eeprom: Pull out transfer length computation

Pull out the code which computes the length of the transfer
into separate code and clean it up a little. This again trims
down the code duplication.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Simon Glass <sjg@chromium.org>
Cc: Tom Rini <trini@konsulko.com>
Cc: Heiko Schocher <hs@denx.de>
Reviewed-by: Heiko Schocher <hs@denx.de>

diff --git a/common/cmd_eeprom.c b/common/cmd_eeprom.c
index 162a05c648bc95af122707d46ba4e9a0c0d0677d..b39ca5d94da06ed295a978ee9c5e3d5bc1295af1 100644 (file)
--- a/common/cmd_eeprom.c
+++ b/common/cmd_eeprom.c
@@ -95,6 +95,29 @@ static int eeprom_addr(unsigned dev_addr, unsigned offset, uchar *addr)
        return alen;
 }
 
+static int eeprom_len(unsigned offset, unsigned end)
+{
+       unsigned len = end - offset;
+
+       /*
+        * For a FRAM device there is no limit on the number of the
+        * bytes that can be ccessed with the single read or write
+        * operation.
+        */
+#if !defined(CONFIG_SYS_I2C_FRAM)
+       unsigned blk_off = offset & 0xff;
+       unsigned maxlen = EEPROM_PAGE_SIZE - EEPROM_PAGE_OFFSET(blk_off);
+
+       if (maxlen > I2C_RXTX_LEN)
+               maxlen = I2C_RXTX_LEN;
+
+       if (len > maxlen)
+               len = maxlen;
+#endif
+
+       return len;
+}
+
 static int eeprom_rw_block(unsigned offset, uchar *addr, unsigned alen,
                           uchar *buffer, unsigned len, bool read)
 {
@@ -126,7 +149,6 @@ static int eeprom_rw_block(unsigned offset, uchar *addr, unsigned alen,
 int eeprom_read (unsigned dev_addr, unsigned offset, uchar *buffer, unsigned cnt)
 {
        unsigned end = offset + cnt;
-       unsigned blk_off;
        int rcode = 0;
        uchar addr[3];
 
@@ -137,27 +159,10 @@ int eeprom_read (unsigned dev_addr, unsigned offset, uchar *buffer, unsigned cnt
         */
        while (offset < end) {
                unsigned alen, len;
-#if !defined(CONFIG_SYS_I2C_FRAM)
-               unsigned maxlen;
-#endif
 
-               blk_off = offset & 0xFF;        /* block offset */
                alen = eeprom_addr(dev_addr, offset, addr);
 
-               len = end - offset;
-
-               /*
-                * For a FRAM device there is no limit on the number of the
-                * bytes that can be ccessed with the single read or write
-                * operation.
-                */
-#if !defined(CONFIG_SYS_I2C_FRAM)
-               maxlen = 0x100 - blk_off;
-               if (maxlen > I2C_RXTX_LEN)
-                       maxlen = I2C_RXTX_LEN;
-               if (len > maxlen)
-                       len = maxlen;
-#endif
+               len = eeprom_len(offset, end);
 
                rcode = eeprom_rw_block(offset, addr, alen, buffer, len, 1);
 
@@ -171,7 +176,6 @@ int eeprom_read (unsigned dev_addr, unsigned offset, uchar *buffer, unsigned cnt
 int eeprom_write (unsigned dev_addr, unsigned offset, uchar *buffer, unsigned cnt)
 {
        unsigned end = offset + cnt;
-       unsigned blk_off;
        int rcode = 0;
        uchar addr[3];
 
@@ -185,30 +189,10 @@ int eeprom_write (unsigned dev_addr, unsigned offset, uchar *buffer, unsigned cn
 
        while (offset < end) {
                unsigned alen, len;
-#if !defined(CONFIG_SYS_I2C_FRAM)
-               unsigned maxlen;
-#endif
 
-               blk_off = offset & 0xFF;        /* block offset */
                alen = eeprom_addr(dev_addr, offset, addr);
 
-               len = end - offset;
-
-               /*
-                * For a FRAM device there is no limit on the number of the
-                * bytes that can be accessed with the single read or write
-                * operation.
-                */
-#if !defined(CONFIG_SYS_I2C_FRAM)
-
-               maxlen = EEPROM_PAGE_SIZE - EEPROM_PAGE_OFFSET(blk_off);
-
-               if (maxlen > I2C_RXTX_LEN)
-                       maxlen = I2C_RXTX_LEN;
-
-               if (len > maxlen)
-                       len = maxlen;
-#endif
+               len = eeprom_len(offset, end);
 
                rcode = eeprom_rw_block(offset, addr, alen, buffer, len, 0);