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authorMiquel Raynal <miquel.raynal@free-electrons.com>2017-09-13 19:21:38 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2017-11-02 11:54:46 +0300
commit176fab4e08a7a578ff6967a8658fd7429faed58f (patch)
treea892783b57028c252dba51f839f7a35ac69e767a
parentc39d070d9d8ce7d6390c10a45695a3c208391e01 (diff)
downloadlinux-176fab4e08a7a578ff6967a8658fd7429faed58f.tar.xz
spi: armada-3700: Fix failing commands with quad-SPI
commit 747e1f60470b975363cbbfcde0c41a3166391be5 upstream. A3700 SPI controller datasheet states that only the first line (IO0) is used to receive and send instructions, addresses and dummy bytes, unless for addresses during an RX operation in a quad SPI configuration (see p.821 of the Armada-3720-DB datasheet). Otherwise, some commands such as SPI NOR commands like READ_FROM_CACHE_DUAL_IO(0xeb) and READ_FROM_CACHE_DUAL_IO(0xbb) will fail because these commands must send address bytes through the four pins. Data transfer always use the four bytes with this setup. Thus, in quad SPI configuration, the A3700_SPI_ADDR_PIN bit must be set only in this case to inform the controller that it must use the number of pins indicated in the {A3700_SPI_DATA_PIN1,A3700_SPI_DATA_PIN0} field during the address cycles of an RX operation. Suggested-by: Ken Ma <make@marvell.com> Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com> Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--drivers/spi/spi-armada-3700.c7
1 files changed, 5 insertions, 2 deletions
diff --git a/drivers/spi/spi-armada-3700.c b/drivers/spi/spi-armada-3700.c
index bd822c32ae3b..53a04267eb38 100644
--- a/drivers/spi/spi-armada-3700.c
+++ b/drivers/spi/spi-armada-3700.c
@@ -161,7 +161,7 @@ static void a3700_spi_deactivate_cs(struct a3700_spi *a3700_spi,
}
static int a3700_spi_pin_mode_set(struct a3700_spi *a3700_spi,
- unsigned int pin_mode)
+ unsigned int pin_mode, bool receiving)
{
u32 val;
@@ -177,6 +177,9 @@ static int a3700_spi_pin_mode_set(struct a3700_spi *a3700_spi,
break;
case SPI_NBITS_QUAD:
val |= A3700_SPI_DATA_PIN1;
+ /* RX during address reception uses 4-pin */
+ if (receiving)
+ val |= A3700_SPI_ADDR_PIN;
break;
default:
dev_err(&a3700_spi->master->dev, "wrong pin mode %u", pin_mode);
@@ -654,7 +657,7 @@ static int a3700_spi_transfer_one(struct spi_master *master,
else if (xfer->rx_buf)
nbits = xfer->rx_nbits;
- a3700_spi_pin_mode_set(a3700_spi, nbits);
+ a3700_spi_pin_mode_set(a3700_spi, nbits, xfer->rx_buf ? true : false);
if (xfer->rx_buf) {
/* Set read data length */