[PATCH 12/15] spi: img-spfi: Use device 0 configuration for all devices

From: Andreas FÃrber
Date: Sun Jul 22 2018 - 17:20:36 EST


From: Ionela Voinescu <ionela.voinescu@xxxxxxxxxx>

Given that we control the chip select line externally,
we can use only one parameter register (device 0 parameter
register) and one set of configuration bits (port configuration
bits for device 0) for all devices (all chip select lines).

Signed-off-by: Ionela Voinescu <ionela.voinescu@xxxxxxxxxx>
Signed-off-by: Andreas FÃrber <afaerber@xxxxxxx>
---
drivers/spi/spi-img-spfi.c | 23 ++++++++++++++++-------
1 file changed, 16 insertions(+), 7 deletions(-)

diff --git a/drivers/spi/spi-img-spfi.c b/drivers/spi/spi-img-spfi.c
index 0d73d31a6a2b..231b59c1ab60 100644
--- a/drivers/spi/spi-img-spfi.c
+++ b/drivers/spi/spi-img-spfi.c
@@ -437,18 +437,23 @@ static int img_spfi_prepare(struct spi_master *master, struct spi_message *msg)
struct img_spfi *spfi = spi_master_get_devdata(master);
u32 val;

+ /*
+ * The chip select line is controlled externally so
+ * we can use the CS0 configuration for all devices
+ */
val = spfi_readl(spfi, SPFI_PORT_STATE);
+
+ /* 0 for device selection */
val &= ~(SPFI_PORT_STATE_DEV_SEL_MASK <<
SPFI_PORT_STATE_DEV_SEL_SHIFT);
- val |= msg->spi->chip_select << SPFI_PORT_STATE_DEV_SEL_SHIFT;
if (msg->spi->mode & SPI_CPHA)
- val |= SPFI_PORT_STATE_CK_PHASE(msg->spi->chip_select);
+ val |= SPFI_PORT_STATE_CK_PHASE(0);
else
- val &= ~SPFI_PORT_STATE_CK_PHASE(msg->spi->chip_select);
+ val &= ~SPFI_PORT_STATE_CK_PHASE(0);
if (msg->spi->mode & SPI_CPOL)
- val |= SPFI_PORT_STATE_CK_POL(msg->spi->chip_select);
+ val |= SPFI_PORT_STATE_CK_POL(0);
else
- val &= ~SPFI_PORT_STATE_CK_POL(msg->spi->chip_select);
+ val &= ~SPFI_PORT_STATE_CK_POL(0);
spfi_writel(spfi, val, SPFI_PORT_STATE);

return 0;
@@ -548,11 +553,15 @@ static void img_spfi_config(struct spi_master *master, struct spi_device *spi,
div = DIV_ROUND_UP(clk_get_rate(spfi->spfi_clk), xfer->speed_hz);
div = clamp(512 / (1 << get_count_order(div)), 1, 128);

- val = spfi_readl(spfi, SPFI_DEVICE_PARAMETER(spi->chip_select));
+ /*
+ * The chip select line is controlled externally so
+ * we can use the CS0 parameters for all devices
+ */
+ val = spfi_readl(spfi, SPFI_DEVICE_PARAMETER(0));
val &= ~(SPFI_DEVICE_PARAMETER_BITCLK_MASK <<
SPFI_DEVICE_PARAMETER_BITCLK_SHIFT);
val |= div << SPFI_DEVICE_PARAMETER_BITCLK_SHIFT;
- spfi_writel(spfi, val, SPFI_DEVICE_PARAMETER(spi->chip_select));
+ spfi_writel(spfi, val, SPFI_DEVICE_PARAMETER(0));

if (!list_is_last(&xfer->transfer_list, &master->cur_msg->transfers) &&
/*
--
2.16.4