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Merge branch 'topic/3wire-gpio' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi into spi-4.21 mode conflict

This commit is contained in:
Mark Brown 2018-12-04 17:31:49 +00:00
parent 32215a6c6b 5132b3d283
commit ae218f7847
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GPG Key ID: 24D68B725D5487D0
2 changed files with 22 additions and 3 deletions
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24
drivers/spi/spi-gpio.c
View File

@ -256,11 +256,29 @@ static int spi_gpio_setup(struct spi_device *spi)
static int spi_gpio_set_direction(struct spi_device *spi, bool output) static int spi_gpio_set_direction(struct spi_device *spi, bool output)
{ {
struct spi_gpio *spi_gpio = spi_to_spi_gpio(spi); struct spi_gpio *spi_gpio = spi_to_spi_gpio(spi);
int ret;
if (output) if (output)
return gpiod_direction_output(spi_gpio->mosi, 1); return gpiod_direction_output(spi_gpio->mosi, 1);
else
return gpiod_direction_input(spi_gpio->mosi); ret = gpiod_direction_input(spi_gpio->mosi);
if (ret)
return ret;
/*
* Send a turnaround high impedance cycle when switching
* from output to input. Theoretically there should be
* a clock delay here, but as has been noted above, the
* nsec delay function for bit-banged GPIO is simply
* {} because bit-banging just doesn't get fast enough
* anyway.
*/
if (spi->mode & SPI_3WIRE_HIZ) {
gpiod_set_value_cansleep(spi_gpio->sck,
!(spi->mode & SPI_CPOL));
gpiod_set_value_cansleep(spi_gpio->sck,
!!(spi->mode & SPI_CPOL));
}
return 0;
} }
static void spi_gpio_cleanup(struct spi_device *spi) static void spi_gpio_cleanup(struct spi_device *spi)
@ -410,7 +428,7 @@ static int spi_gpio_probe(struct platform_device *pdev)
return status; return status;
master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32); master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
master->mode_bits = SPI_3WIRE | SPI_CPHA | SPI_CPOL; master->mode_bits = SPI_3WIRE | SPI_3WIRE_HIZ | SPI_CPHA | SPI_CPOL;
master->flags = master_flags; master->flags = master_flags;
master->bus_num = pdev->id; master->bus_num = pdev->id;
/* The master needs to think there is a chipselect even if not connected */ /* The master needs to think there is a chipselect even if not connected */

1
include/linux/spi/spi.h
View File

@ -157,6 +157,7 @@ struct spi_device {
#define SPI_CS_WORD 0x1000 /* toggle cs after each word */ #define SPI_CS_WORD 0x1000 /* toggle cs after each word */
#define SPI_TX_OCTAL 0x2000 /* transmit with 8 wires */ #define SPI_TX_OCTAL 0x2000 /* transmit with 8 wires */
#define SPI_RX_OCTAL 0x4000 /* receive with 8 wires */ #define SPI_RX_OCTAL 0x4000 /* receive with 8 wires */
#define SPI_3WIRE_HIZ 0x8000 /* high impedance turnaround */
int irq; int irq;
void *controller_state; void *controller_state;
void *controller_data; void *controller_data;