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Subject[PATCH v2] spi: atmel: Fix CS and initialization bug
Date
Commit 5fa5e6dec762 ("spi: atmel: Switch to transfer_one transfer
method") switched to using transfer_one and set_cs. The
core doesn't call set_cs when the chip select lines are gpios. Add the
SPI_MASTER_GPIO_SS flag to the driver to ensure the calls to set_cs
happen since the driver programs configuration registers there.

Fixes: 5fa5e6dec762 ("spi: atmel: Switch to transfer_one transfer method")

Signed-off-by: Dan Sneddon <dan.sneddon@microchip.com>
---

Changes in v2:
- Updated commit message
- Dropped unnecessary change to enable variable in set_cs

drivers/spi/spi-atmel.c | 9 ++-------
1 file changed, 2 insertions(+), 7 deletions(-)

diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
index 2ef74885ffa2..788dcdf25f00 100644
--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -352,8 +352,6 @@ static void cs_activate(struct atmel_spi *as, struct spi_device *spi)
}

mr = spi_readl(as, MR);
- if (spi->cs_gpiod)
- gpiod_set_value(spi->cs_gpiod, 1);
} else {
u32 cpol = (spi->mode & SPI_CPOL) ? SPI_BIT(CPOL) : 0;
int i;
@@ -369,8 +367,6 @@ static void cs_activate(struct atmel_spi *as, struct spi_device *spi)

mr = spi_readl(as, MR);
mr = SPI_BFINS(PCS, ~(1 << chip_select), mr);
- if (spi->cs_gpiod)
- gpiod_set_value(spi->cs_gpiod, 1);
spi_writel(as, MR, mr);
}

@@ -400,8 +396,6 @@ static void cs_deactivate(struct atmel_spi *as, struct spi_device *spi)

if (!spi->cs_gpiod)
spi_writel(as, CR, SPI_BIT(LASTXFER));
- else
- gpiod_set_value(spi->cs_gpiod, 0);
}

static void atmel_spi_lock(struct atmel_spi *as) __acquires(&as->lock)
@@ -1483,7 +1477,8 @@ static int atmel_spi_probe(struct platform_device *pdev)
master->bus_num = pdev->id;
master->num_chipselect = 4;
master->setup = atmel_spi_setup;
- master->flags = (SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX);
+ master->flags = (SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX |
+ SPI_MASTER_GPIO_SS);
master->transfer_one = atmel_spi_one_transfer;
master->set_cs = atmel_spi_set_cs;
master->cleanup = atmel_spi_cleanup;
--
2.17.1
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