Certain spi controllers may provide accelerated interface to read from
m25p80 type flash devices. This interface provides better read
performance than regular SPI interface.
Call spi_flash_read(), if supported, to make use of such interface.
Signed-off-by: Vignesh R <vigneshr@xxxxxx>
---
v4:
* Use spi_flash_read_message struct to pass args.
* support passing of opcode/addr/data nbits.
drivers/mtd/devices/m25p80.c | 20 ++++++++++++++++++++
1 file changed, 20 insertions(+)
diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c
index fe9ceb7b5405..00094a668c62 100644
--- a/drivers/mtd/devices/m25p80.c
+++ b/drivers/mtd/devices/m25p80.c
@@ -131,6 +131,26 @@ static int m25p80_read(struct spi_nor *nor, loff_t from, size_t len,
/* convert the dummy cycles to the number of bytes */
dummy /= 8;
+ if (spi_flash_read_supported(spi)) {
+ struct spi_flash_read_message msg;
+ int ret;
+
+ msg.buf = buf;
+ msg.from = from;
+ msg.len = len;
+ msg.read_opcode = nor->read_opcode;
+ msg.addr_width = nor->addr_width;
+ msg.dummy_bytes = dummy;
+ /* TODO: Support other combinations */
+ msg.opcode_nbits = SPI_NBITS_SINGLE;
+ msg.addr_nbits = SPI_NBITS_SINGLE;
+ msg.data_nbits = m25p80_rx_nbits(nor);
+
+ ret = spi_flash_read(spi, &msg);
+ *retlen = msg.retlen;
+ return ret;
+ }
+
spi_message_init(&m);
memset(t, 0, (sizeof t));
--
2.6.3
--
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