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authorMark Brown <broonie@kernel.org>2023-05-30 19:43:31 +0300
committerMark Brown <broonie@kernel.org>2023-05-30 19:43:31 +0300
commitfe73245592fef75a7c41180a3fbb07c9a75f622e (patch)
tree2b4964fcd8f518de998ffe57f1dfff63a16cf60f /drivers/spi
parent0bbb363f86f2215571741bc945f6b9ec132ea1b8 (diff)
parentb229a7f530ebea90c8e21b56872f3102e3d54461 (diff)
downloadlinux-fe73245592fef75a7c41180a3fbb07c9a75f622e.tar.xz
spi: add SPI_MOSI_IDLE_LOW mode bit
Merge series from Boerge Struempfel <boerge.struempfel@gmail.com>: Some spi controller switch the mosi line to high, whenever they are idle. This may not be desired in all use cases. For example neopixel leds can get confused and flicker due to misinterpreting the idle state. Therefore, we introduce a new spi-mode bit, with which the idle behaviour can be overwritten on a per device basis.
Diffstat (limited to 'drivers/spi')
-rw-r--r--drivers/spi/spi-imx.c9
-rw-r--r--drivers/spi/spidev.c3
2 files changed, 10 insertions, 2 deletions
diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c
index bd6ddb142b13..6f4d3cb81fdf 100644
--- a/drivers/spi/spi-imx.c
+++ b/drivers/spi/spi-imx.c
@@ -281,6 +281,7 @@ static bool spi_imx_can_dma(struct spi_controller *controller, struct spi_device
#define MX51_ECSPI_CONFIG_SCLKPOL(cs) (1 << ((cs & 3) + 4))
#define MX51_ECSPI_CONFIG_SBBCTRL(cs) (1 << ((cs & 3) + 8))
#define MX51_ECSPI_CONFIG_SSBPOL(cs) (1 << ((cs & 3) + 12))
+#define MX51_ECSPI_CONFIG_DATACTL(cs) (1 << ((cs & 3) + 16))
#define MX51_ECSPI_CONFIG_SCLKCTL(cs) (1 << ((cs & 3) + 20))
#define MX51_ECSPI_INT 0x10
@@ -573,6 +574,11 @@ static int mx51_ecspi_prepare_message(struct spi_imx_data *spi_imx,
cfg &= ~MX51_ECSPI_CONFIG_SCLKCTL(spi_get_chipselect(spi, 0));
}
+ if (spi->mode & SPI_MOSI_IDLE_LOW)
+ cfg |= MX51_ECSPI_CONFIG_DATACTL(spi_get_chipselect(spi, 0));
+ else
+ cfg &= ~MX51_ECSPI_CONFIG_DATACTL(spi_get_chipselect(spi, 0));
+
if (spi->mode & SPI_CS_HIGH)
cfg |= MX51_ECSPI_CONFIG_SSBPOL(spi_get_chipselect(spi, 0));
else
@@ -1743,7 +1749,8 @@ static int spi_imx_probe(struct platform_device *pdev)
controller->prepare_message = spi_imx_prepare_message;
controller->unprepare_message = spi_imx_unprepare_message;
controller->slave_abort = spi_imx_slave_abort;
- controller->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_NO_CS;
+ controller->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_NO_CS |
+ SPI_MOSI_IDLE_LOW;
if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx) ||
is_imx53_ecspi(spi_imx))
diff --git a/drivers/spi/spidev.c b/drivers/spi/spidev.c
index 39d94c850839..c8b938e0f342 100644
--- a/drivers/spi/spidev.c
+++ b/drivers/spi/spidev.c
@@ -64,7 +64,8 @@ static_assert(N_SPI_MINORS > 0 && N_SPI_MINORS <= 256);
| SPI_NO_CS | SPI_READY | SPI_TX_DUAL \
| SPI_TX_QUAD | SPI_TX_OCTAL | SPI_RX_DUAL \
| SPI_RX_QUAD | SPI_RX_OCTAL \
- | SPI_RX_CPHA_FLIP)
+ | SPI_RX_CPHA_FLIP | SPI_3WIRE_HIZ \
+ | SPI_MOSI_IDLE_LOW)
struct spidev_data {
dev_t devt;