brcm63xx: fix legacy spi tranfers >= 256 bytes

Fixes e.g. SPI flash access on BCM6358/BCM6368. Transfers < 256 bytes
are not affected.

Signed-off-by: Jonas Gorski <jogo@openwrt.org>

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@39265 3c298f89-4303-0410-b956-a3cf2f4a3e73

target/linux/brcm63xx/patches-3.10/054-spi-bcm63xx-don-t-substract-prepend-length-from-tota.patch

@@ -0,0 +1,26 @@
+From e85583b12b023773b488cf8406f11719a4037461 Mon Sep 17 00:00:00 2001
+From: Jonas Gorski <jogo@openwrt.org>
+Date: Sun, 1 Dec 2013 16:16:44 +0100
+Subject: [PATCH 1/2] spi/bcm63xx: don't substract prepend length from total
+ length
+
+The spi command must include the full message length including any
+prepended writes, else transfers larger than 256 bytes will be
+incomplete.
+
+Signed-off-by: Jonas Gorski <jogo@openwrt.org>
+---
+ drivers/spi/spi-bcm63xx.c | 2 --
+ 1 file changed, 2 deletions(-)
+
+--- a/drivers/spi/spi-bcm63xx.c
++++ b/drivers/spi/spi-bcm63xx.c
+@@ -180,8 +180,6 @@ static int bcm63xx_txrx_bufs(struct spi_
+ 			       transfer_list);
+ 	}
+ 
+-	len -= prepend_len;
+-
+ 	init_completion(&bs->done);
+ 
+ 	/* Fill in the Message control register */

target/linux/brcm63xx/patches-3.10/055-spi-bcm63xx-don-t-reject-reads-256-bytes.patch

@@ -0,0 +1,31 @@
+From 4d8fa9d3d1fe1d70fe7d59537acf49797f6010a1 Mon Sep 17 00:00:00 2001
+From: Jonas Gorski <jogo@openwrt.org>
+Date: Sun, 1 Dec 2013 16:19:46 +0100
+Subject: [PATCH 2/2] spi/bcm63xx: don't reject reads >= 256 bytes
+
+The rx_tail register is only 8 bit wide, so it will wrap around
+after 256 read bytes. This makes it rather meaningless, so drop any
+usage of it to not treat reads over 256 as failed.
+
+Signed-off-by: Jonas Gorski <jogo@openwrt.org>
+---
+ drivers/spi/spi-bcm63xx.c | 8 +-------
+ 1 file changed, 1 insertion(+), 7 deletions(-)
+
+--- a/drivers/spi/spi-bcm63xx.c
++++ b/drivers/spi/spi-bcm63xx.c
+@@ -214,13 +214,7 @@ static int bcm63xx_txrx_bufs(struct spi_
+ 	if (!timeout)
+ 		return -ETIMEDOUT;
+ 
+-	/* read out all data */
+-	rx_tail = bcm_spi_readb(bs, SPI_RX_TAIL);
+-
+-	if (do_rx && rx_tail != len)
+-		return -EIO;
+-
+-	if (!rx_tail)
++	if (!do_rx)
+ 		return 0;
+ 
+ 	len = 0;