ramips: restore the mediatek-4-byte-spi-reset.patch

patch was dropped in commit 447cf1a2b7efa3949c8562d08bddcfaba3a5d809

Signed-off-by: L. D. Pinney <ldpinney@gmail.com>

diff --git a/target/linux/ramips/patches-4.4/0902-mediatek-4-byte-spi-reset.patch b/target/linux/ramips/patches-4.4/0902-mediatek-4-byte-spi-reset.patch
new file mode 100644 (file)
index 0000000..2ef5cf0
--- /dev/null
+++ b/target/linux/ramips/patches-4.4/0902-mediatek-4-byte-spi-reset.patch
@@ -0,0 +1,43 @@
+diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c
+index fe9ceb7..2151975 100644
+--- a/drivers/mtd/devices/m25p80.c
++++ b/drivers/mtd/devices/m25p80.c
+@@ -27,6 +27,9 @@
+ #include <linux/spi/flash.h>
+ #include <linux/mtd/spi-nor.h>
+ 
++#define OPCODE_RESET_ENABLE   0x66
++#define OPCODE_RESET          0x99
++
+ #define       MAX_CMD_SIZE            6
+ struct m25p {
+       struct spi_device       *spi;
+@@ -168,6 +171,17 @@ static int m25p80_erase(struct spi_nor *nor, loff_t offset)
+       return 0;
+ }
+ 
++void m25p80_reboot(struct mtd_info *mtd)
++{
++      struct spi_nor *nor = container_of(mtd, struct spi_nor, mtd);
++      struct m25p *flash = nor->priv;
++
++      flash->command[0] = OPCODE_RESET_ENABLE;
++      spi_write(flash->spi, flash->command, 1);
++      flash->command[0] = OPCODE_RESET;
++      spi_write(flash->spi, flash->command, 1);
++}
++
+ /*
+  * board specific setup should have ensured the SPI clock used here
+  * matches what the READ command supports, at least until this driver
+@@ -197,6 +211,7 @@ static int m25p_probe(struct spi_device *spi)
+       nor->erase = m25p80_erase;
+       nor->write_reg = m25p80_write_reg;
+       nor->read_reg = m25p80_read_reg;
++      nor->mtd._reboot = m25p80_reboot;
+ 
+       nor->dev = &spi->dev;
+       nor->flash_node = spi->dev.of_node;
+-- 
+2.9.3
+