Unverified Commit bf749955 authored by Mark Brown's avatar Mark Brown
Browse files

spi: Abstract access to chip selects 

Merge series from Amit Kumar Mahapatra <amit.kumar-mahapatra@amd.com>:

In preparation for supporting devices with multiple chip selects add an
interface for accessing the chip selects via a function.
parents d4bde043 303feb3c

drivers/spi/spi.c

+22 −23
Original line number Diff line number Diff line
@@ -604,7 +604,7 @@ static void spi_dev_set_name(struct spi_device *spi) 
	}



	dev_set_name(&spi->dev, "%s.%u", dev_name(&spi->controller->dev),

		     spi->chip_select);

		     spi_get_chipselect(spi, 0));

}



static int spi_dev_check(struct device *dev, void *data)
@@ -613,7 +613,7 @@ static int spi_dev_check(struct device *dev, void *data) 
	struct spi_device *new_spi = data;



	if (spi->controller == new_spi->controller &&

	    spi->chip_select == new_spi->chip_select)

	    spi_get_chipselect(spi, 0) == spi_get_chipselect(new_spi, 0))

		return -EBUSY;

	return 0;

}
@@ -638,7 +638,7 @@ static int __spi_add_device(struct spi_device *spi) 
	status = bus_for_each_dev(&spi_bus_type, NULL, spi, spi_dev_check);

	if (status) {

		dev_err(dev, "chipselect %d already in use\n",

				spi->chip_select);

				spi_get_chipselect(spi, 0));

		return status;

	}
@@ -649,7 +649,7 @@ static int __spi_add_device(struct spi_device *spi) 
	}



	if (ctlr->cs_gpiods)

		spi->cs_gpiod = ctlr->cs_gpiods[spi->chip_select];

		spi_set_csgpiod(spi, 0, ctlr->cs_gpiods[spi_get_chipselect(spi, 0)]);



	/*

	 * Drivers may modify this initial i/o setup, but will
@@ -692,8 +692,8 @@ int spi_add_device(struct spi_device *spi) 
	int status;



	/* Chipselects are numbered 0..max; validate. */

	if (spi->chip_select >= ctlr->num_chipselect) {

		dev_err(dev, "cs%d >= max %d\n", spi->chip_select,

	if (spi_get_chipselect(spi, 0) >= ctlr->num_chipselect) {

		dev_err(dev, "cs%d >= max %d\n", spi_get_chipselect(spi, 0),

			ctlr->num_chipselect);

		return -EINVAL;

	}
@@ -714,8 +714,8 @@ static int spi_add_device_locked(struct spi_device *spi) 
	struct device *dev = ctlr->dev.parent;



	/* Chipselects are numbered 0..max; validate. */

	if (spi->chip_select >= ctlr->num_chipselect) {

		dev_err(dev, "cs%d >= max %d\n", spi->chip_select,

	if (spi_get_chipselect(spi, 0) >= ctlr->num_chipselect) {

		dev_err(dev, "cs%d >= max %d\n", spi_get_chipselect(spi, 0),

			ctlr->num_chipselect);

		return -EINVAL;

	}
@@ -761,7 +761,7 @@ struct spi_device *spi_new_device(struct spi_controller *ctlr, 


	WARN_ON(strlen(chip->modalias) >= sizeof(proxy->modalias));



	proxy->chip_select = chip->chip_select;

	spi_set_chipselect(proxy, 0, chip->chip_select);

	proxy->max_speed_hz = chip->max_speed_hz;

	proxy->mode = chip->mode;

	proxy->irq = chip->irq;
@@ -970,24 +970,23 @@ static void spi_set_cs(struct spi_device *spi, bool enable, bool force) 
	 * Avoid calling into the driver (or doing delays) if the chip select

	 * isn't actually changing from the last time this was called.

	 */

	if (!force && ((enable && spi->controller->last_cs == spi->chip_select) ||

				(!enable && spi->controller->last_cs != spi->chip_select)) &&

	if (!force && ((enable && spi->controller->last_cs == spi_get_chipselect(spi, 0)) ||

		       (!enable && spi->controller->last_cs != spi_get_chipselect(spi, 0))) &&

	    (spi->controller->last_cs_mode_high == (spi->mode & SPI_CS_HIGH)))

		return;



	trace_spi_set_cs(spi, activate);



	spi->controller->last_cs = enable ? spi->chip_select : -1;

	spi->controller->last_cs = enable ? spi_get_chipselect(spi, 0) : -1;

	spi->controller->last_cs_mode_high = spi->mode & SPI_CS_HIGH;



	if ((spi->cs_gpiod || !spi->controller->set_cs_timing) && !activate) {

	if ((spi_get_csgpiod(spi, 0) || !spi->controller->set_cs_timing) && !activate)

		spi_delay_exec(&spi->cs_hold, NULL);

	}



	if (spi->mode & SPI_CS_HIGH)

		enable = !enable;



	if (spi->cs_gpiod) {

	if (spi_get_csgpiod(spi, 0)) {

		if (!(spi->mode & SPI_NO_CS)) {

			/*

			 * Historically ACPI has no means of the GPIO polarity and
@@ -1000,10 +999,10 @@ static void spi_set_cs(struct spi_device *spi, bool enable, bool force) 
			 * into account.

			 */

			if (has_acpi_companion(&spi->dev))

				gpiod_set_value_cansleep(spi->cs_gpiod, !enable);

				gpiod_set_value_cansleep(spi_get_csgpiod(spi, 0), !enable);

			else

				/* Polarity handled by GPIO library */

				gpiod_set_value_cansleep(spi->cs_gpiod, activate);

				gpiod_set_value_cansleep(spi_get_csgpiod(spi, 0), activate);

		}

		/* Some SPI masters need both GPIO CS & slave_select */

		if ((spi->controller->flags & SPI_MASTER_GPIO_SS) &&
@@ -1013,7 +1012,7 @@ static void spi_set_cs(struct spi_device *spi, bool enable, bool force) 
		spi->controller->set_cs(spi, !enable);

	}



	if (spi->cs_gpiod || !spi->controller->set_cs_timing) {

	if (spi_get_csgpiod(spi, 0) || !spi->controller->set_cs_timing) {

		if (activate)

			spi_delay_exec(&spi->cs_setup, NULL);

		else
@@ -2319,7 +2318,7 @@ static int of_spi_parse_dt(struct spi_controller *ctlr, struct spi_device *spi, 
			nc, rc);

		return rc;

	}

	spi->chip_select = value;

	spi_set_chipselect(spi, 0, value);



	/* Device speed */

	if (!of_property_read_u32(nc, "spi-max-frequency", &value))
@@ -2438,7 +2437,7 @@ struct spi_device *spi_new_ancillary_device(struct spi_device *spi, 
	strscpy(ancillary->modalias, "dummy", sizeof(ancillary->modalias));



	/* Use provided chip-select for ancillary device */

	ancillary->chip_select = chip_select;

	spi_set_chipselect(ancillary, 0, chip_select);



	/* Take over SPI mode/speed from SPI main device */

	ancillary->max_speed_hz = spi->max_speed_hz;
@@ -2685,7 +2684,7 @@ struct spi_device *acpi_spi_device_alloc(struct spi_controller *ctlr, 
	spi->mode		|= lookup.mode;

	spi->irq		= lookup.irq;

	spi->bits_per_word	= lookup.bits_per_word;

	spi->chip_select	= lookup.chip_select;

	spi_set_chipselect(spi, 0, lookup.chip_select);



	return spi;

}
@@ -3647,7 +3646,7 @@ static int spi_set_cs_timing(struct spi_device *spi) 
	struct device *parent = spi->controller->dev.parent;

	int status = 0;



	if (spi->controller->set_cs_timing && !spi->cs_gpiod) {

	if (spi->controller->set_cs_timing && !spi_get_csgpiod(spi, 0)) {

		if (spi->controller->auto_runtime_pm) {

			status = pm_runtime_get_sync(parent);

			if (status < 0) {
@@ -3852,7 +3851,7 @@ static int __spi_validate(struct spi_device *spi, struct spi_message *message) 
	 * cs_change is set for each transfer.

	 */

	if ((spi->mode & SPI_CS_WORD) && (!(ctlr->mode_bits & SPI_CS_WORD) ||

					  spi->cs_gpiod)) {

					  spi_get_csgpiod(spi, 0))) {

		size_t maxsize;

		int ret;

include/linux/spi/spi.h

+20 −0
Original line number Diff line number Diff line
@@ -263,6 +263,26 @@ static inline void *spi_get_drvdata(struct spi_device *spi) 
	return dev_get_drvdata(&spi->dev);

}



static inline u8 spi_get_chipselect(struct spi_device *spi, u8 idx)

{

	return spi->chip_select;

}



static inline void spi_set_chipselect(struct spi_device *spi, u8 idx, u8 chipselect)

{

	spi->chip_select = chipselect;

}



static inline struct gpio_desc *spi_get_csgpiod(struct spi_device *spi, u8 idx)

{

	return spi->cs_gpiod;

}



static inline void spi_set_csgpiod(struct spi_device *spi, u8 idx, struct gpio_desc *csgpiod)

{

	spi->cs_gpiod = csgpiod;

}



struct spi_message;



/**