Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Unverified Commit 4b859db2 authored by Lorenzo Bianconi's avatar Lorenzo Bianconi Committed by Mark Brown
Browse files

spi: spi-gpio: add SPI_3WIRE support 



Add SPI_3WIRE support to spi-gpio controller introducing
set_line_direction function pointer in spi_bitbang data structure.
Spi-gpio controller has been tested using hts221 temp/rh iio sensor
running in 3wire mode and lsm6dsm running in 4wire mode

Signed-off-by: default avatarLorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent 304d3436

drivers/spi/spi-bitbang.c

+16 −0
Original line number Original line Diff line number Diff line
@@ -243,7 +243,23 @@ static int spi_bitbang_bufs(struct spi_device *spi, struct spi_transfer *t) 
{

{

	struct spi_bitbang_cs	*cs = spi->controller_state;

	struct spi_bitbang_cs	*cs = spi->controller_state;

	unsigned		nsecs = cs->nsecs;

	unsigned		nsecs = cs->nsecs;

	struct spi_bitbang	*bitbang;



	bitbang = spi_master_get_devdata(spi->master);

	if (bitbang->set_line_direction) {

		int err;





		err = bitbang->set_line_direction(spi, !!(t->tx_buf));

		if (err < 0)

			return err;

	}



	if (spi->mode & SPI_3WIRE) {

		unsigned flags;



		flags = t->tx_buf ? SPI_MASTER_NO_RX : SPI_MASTER_NO_TX;

		return cs->txrx_bufs(spi, cs->txrx_word, nsecs, t, flags);

	}

	return cs->txrx_bufs(spi, cs->txrx_word, nsecs, t, 0);

	return cs->txrx_bufs(spi, cs->txrx_word, nsecs, t, 0);

}

}

drivers/spi/spi-gpio.c

+16 −1
Original line number Original line Diff line number Diff line
@@ -121,6 +121,9 @@ static inline int getmiso(const struct spi_device *spi) 
{

{

	struct spi_gpio *spi_gpio = spi_to_spi_gpio(spi);

	struct spi_gpio *spi_gpio = spi_to_spi_gpio(spi);





	if (spi->mode & SPI_3WIRE)

		return !!gpiod_get_value_cansleep(spi_gpio->mosi);

	else

		return !!gpiod_get_value_cansleep(spi_gpio->miso);

		return !!gpiod_get_value_cansleep(spi_gpio->miso);

}

}
@@ -250,6 +253,16 @@ static int spi_gpio_setup(struct spi_device *spi) 
	return status;

	return status;

}

}





static int spi_gpio_set_direction(struct spi_device *spi, bool output)

{

	struct spi_gpio *spi_gpio = spi_to_spi_gpio(spi);



	if (output)

		return gpiod_direction_output(spi_gpio->mosi, 1);

	else

		return gpiod_direction_input(spi_gpio->mosi);

}



static void spi_gpio_cleanup(struct spi_device *spi)

static void spi_gpio_cleanup(struct spi_device *spi)

{

{

	spi_bitbang_cleanup(spi);

	spi_bitbang_cleanup(spi);
@@ -395,6 +408,7 @@ 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->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 */
@@ -407,6 +421,7 @@ static int spi_gpio_probe(struct platform_device *pdev) 




	spi_gpio->bitbang.master = master;

	spi_gpio->bitbang.master = master;

	spi_gpio->bitbang.chipselect = spi_gpio_chipselect;

	spi_gpio->bitbang.chipselect = spi_gpio_chipselect;

	spi_gpio->bitbang.set_line_direction = spi_gpio_set_direction;





	if ((master_flags & (SPI_MASTER_NO_TX | SPI_MASTER_NO_RX)) == 0) {

	if ((master_flags & (SPI_MASTER_NO_TX | SPI_MASTER_NO_RX)) == 0) {

		spi_gpio->bitbang.txrx_word[SPI_MODE_0] = spi_gpio_txrx_word_mode0;

		spi_gpio->bitbang.txrx_word[SPI_MODE_0] = spi_gpio_txrx_word_mode0;

include/linux/spi/spi_bitbang.h

+1 −0
Original line number Original line Diff line number Diff line
@@ -31,6 +31,7 @@ struct spi_bitbang { 
	u32	(*txrx_word[4])(struct spi_device *spi,

	u32	(*txrx_word[4])(struct spi_device *spi,

			unsigned nsecs,

			unsigned nsecs,

			u32 word, u8 bits, unsigned flags);

			u32 word, u8 bits, unsigned flags);

	int	(*set_line_direction)(struct spi_device *spi, bool output);

};

};





/* you can call these default bitbang->master methods from your custom

/* you can call these default bitbang->master methods from your custom