[LINUX PATCH 1/2] mtd: Added dummy entry in the spi_transfer structure.

From: P L Sai Krishna
Date: Mon Mar 21 2016 - 08:35:05 EST


This patch does following things.
1. Added dummy entry in the spi_transfer structure.
2. Assigned dummy cycles to dummy member in the transfer
structure during read operation.

Signed-off-by: P L Sai Krishna <lakshmis@xxxxxxxxxx>
---
drivers/mtd/devices/m25p80.c | 1 +
include/linux/spi/spi.h | 2 ++
2 files changed, 3 insertions(+)

diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c
index c9c3b7f..7c9fac9 100644
--- a/drivers/mtd/devices/m25p80.c
+++ b/drivers/mtd/devices/m25p80.c
@@ -139,6 +139,7 @@ static int m25p80_read(struct spi_nor *nor, loff_t from, size_t len,

t[0].tx_buf = flash->command;
t[0].len = m25p_cmdsz(nor) + dummy;
+ t[0].dummy = nor->read_dummy;
spi_message_add_tail(&t[0], &m);

t[1].rx_buf = buf;
diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h
index 857a9a1..3f93526 100644
--- a/include/linux/spi/spi.h
+++ b/include/linux/spi/spi.h
@@ -664,6 +664,7 @@ extern void spi_res_release(struct spi_master *master,
* @len: size of rx and tx buffers (in bytes)
* @speed_hz: Select a speed other than the device default for this
* transfer. If 0 the default (from @spi_device) is used.
+ * @dummy: number of dummy cycles.
* @bits_per_word: select a bits_per_word other than the device default
* for this transfer. If 0 the default (from @spi_device) is used.
* @cs_change: affects chipselect after this transfer completes
@@ -752,6 +753,7 @@ struct spi_transfer {
u8 bits_per_word;
u16 delay_usecs;
u32 speed_hz;
+ u32 dummy;

struct list_head transfer_list;
};
--
2.1.2