Unverified Commit 249e2632 authored by Andrey Smirnov's avatar Andrey Smirnov Committed by Mark Brown
Browse files

spi: gpio: Don't request CS GPIO in DT use-case 



DT use-case already relies on SPI core to control CS (requested by
of_spi_register_master() and controlled spi_set_cs()), so there's no
need to try to request those GPIO in spi-gpio code. Change the code
such that spi-gpio's CS related code is only used if device is probed
via pdata.

Signed-off-by: default avatarAndrey Smirnov <andrew.smirnov@gmail.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Chris Healy <cphealy@gmail.com>
Cc: linux-spi@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent d9088966

drivers/spi/spi-gpio.c

+59 −75
Original line number Diff line number Diff line
@@ -46,7 +46,6 @@ struct spi_gpio { 
	struct gpio_desc		*miso;

	struct gpio_desc		*mosi;

	struct gpio_desc		**cs_gpios;

	bool				has_cs;

};



/*----------------------------------------------------------------------*/
@@ -216,7 +215,7 @@ static void spi_gpio_chipselect(struct spi_device *spi, int is_active) 
		gpiod_set_value_cansleep(spi_gpio->sck, spi->mode & SPI_CPOL);



	/* Drive chip select line, if we have one */

	if (spi_gpio->has_cs) {

	if (spi_gpio->cs_gpios) {

		struct gpio_desc *cs = spi_gpio->cs_gpios[spi->chip_select];



		/* SPI chip selects are normally active-low */
@@ -234,10 +233,12 @@ static int spi_gpio_setup(struct spi_device *spi) 
	 * The CS GPIOs have already been

	 * initialized from the descriptor lookup.

	 */

	if (spi_gpio->cs_gpios) {

		cs = spi_gpio->cs_gpios[spi->chip_select];

		if (!spi->controller_state && cs)

			status = gpiod_direction_output(cs,

						  !(spi->mode & SPI_CS_HIGH));

	}



	if (!status)

		status = spi_bitbang_setup(spi);
@@ -290,11 +291,8 @@ static void spi_gpio_cleanup(struct spi_device *spi) 
 */

static int spi_gpio_request(struct device *dev,

			    struct spi_gpio *spi_gpio,

			    unsigned int num_chipselects,

			    u16 *mflags)

{

	int i;



	spi_gpio->mosi = devm_gpiod_get_optional(dev, "mosi", GPIOD_OUT_LOW);

	if (IS_ERR(spi_gpio->mosi))

		return PTR_ERR(spi_gpio->mosi);
@@ -315,13 +313,6 @@ static int spi_gpio_request(struct device *dev, 
	if (IS_ERR(spi_gpio->sck))

		return PTR_ERR(spi_gpio->sck);



	for (i = 0; i < num_chipselects; i++) {

		spi_gpio->cs_gpios[i] = devm_gpiod_get_index(dev, "cs",

							     i, GPIOD_OUT_HIGH);

		if (IS_ERR(spi_gpio->cs_gpios[i]))

			return PTR_ERR(spi_gpio->cs_gpios[i]);

	}



	return 0;

}
@@ -332,90 +323,87 @@ static const struct of_device_id spi_gpio_dt_ids[] = { 
};

MODULE_DEVICE_TABLE(of, spi_gpio_dt_ids);



static int spi_gpio_probe_dt(struct platform_device *pdev)

static int spi_gpio_probe_dt(struct platform_device *pdev,

			     struct spi_master *master)

{

	int ret;

	u32 tmp;

	struct spi_gpio_platform_data	*pdata;

	struct device_node *np = pdev->dev.of_node;

	const struct of_device_id *of_id =

			of_match_device(spi_gpio_dt_ids, &pdev->dev);

	master->dev.of_node = pdev->dev.of_node;

	master->use_gpio_descriptors = true;



	if (!of_id)

	return 0;



	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);

	if (!pdata)

		return -ENOMEM;





	ret = of_property_read_u32(np, "num-chipselects", &tmp);

	if (ret < 0) {

		dev_err(&pdev->dev, "num-chipselects property not found\n");

		goto error_free;

}

#else

static inline int spi_gpio_probe_dt(struct platform_device *pdev,

				    struct spi_master *master)

{

	return 0;

}

#endif



	pdata->num_chipselect = tmp;

	pdev->dev.platform_data = pdata;

static int spi_gpio_probe_pdata(struct platform_device *pdev,

				struct spi_master *master)

{

	struct device *dev = &pdev->dev;

	struct spi_gpio_platform_data *pdata = dev_get_platdata(dev);

	struct spi_gpio *spi_gpio = spi_master_get_devdata(master);

	int i;



	return 1;

#ifdef GENERIC_BITBANG

	if (!pdata || !pdata->num_chipselect)

		return -ENODEV;

#endif

	/*

	 * The master needs to think there is a chipselect even if not

	 * connected

	 */

	master->num_chipselect = pdata->num_chipselect ?: 1;



error_free:

	devm_kfree(&pdev->dev, pdata);

	return ret;

	spi_gpio->cs_gpios = devm_kcalloc(dev, master->num_chipselect,

					  sizeof(*spi_gpio->cs_gpios),

					  GFP_KERNEL);

	if (!spi_gpio->cs_gpios)

		return -ENOMEM;



	for (i = 0; i < master->num_chipselect; i++) {

		spi_gpio->cs_gpios[i] = devm_gpiod_get_index(dev, "cs", i,

							     GPIOD_OUT_HIGH);

		if (IS_ERR(spi_gpio->cs_gpios[i]))

			return PTR_ERR(spi_gpio->cs_gpios[i]);

	}

#else

static inline int spi_gpio_probe_dt(struct platform_device *pdev)

{



	return 0;

}

#endif



static int spi_gpio_probe(struct platform_device *pdev)

{

	int				status;

	struct spi_master		*master;

	struct spi_gpio			*spi_gpio;

	struct spi_gpio_platform_data	*pdata;

	struct device			*dev = &pdev->dev;

	struct spi_bitbang		*bb;

	const struct of_device_id	*of_id;

	u16 master_flags = 0;

	bool use_of = 0;



	status = spi_gpio_probe_dt(pdev);

	if (status < 0)

		return status;

	if (status > 0)

		use_of = 1;



	pdata = dev_get_platdata(dev);

#ifdef GENERIC_BITBANG

	if (!pdata || (!use_of && !pdata->num_chipselect))

		return -ENODEV;

#endif

	of_id = of_match_device(spi_gpio_dt_ids, &pdev->dev);



	master = spi_alloc_master(dev, sizeof(*spi_gpio));

	if (!master)

		return -ENOMEM;



	spi_gpio = spi_master_get_devdata(master);

	if (of_id)

		status = spi_gpio_probe_dt(pdev, master);

	else

		status = spi_gpio_probe_pdata(pdev, master);



	spi_gpio->cs_gpios = devm_kcalloc(dev,

				pdata->num_chipselect,

				sizeof(*spi_gpio->cs_gpios),

				GFP_KERNEL);

	if (!spi_gpio->cs_gpios)

		return -ENOMEM;

	if (status)

		return status;



	platform_set_drvdata(pdev, spi_gpio);

	spi_gpio = spi_master_get_devdata(master);



	/* Determine if we have chip selects connected */

	spi_gpio->has_cs = !!pdata->num_chipselect;

	platform_set_drvdata(pdev, spi_gpio);



	spi_gpio->pdev = pdev;



	status = spi_gpio_request(dev, spi_gpio,

				  pdata->num_chipselect, &master_flags);

	status = spi_gpio_request(dev, spi_gpio, &master_flags);

	if (status)

		return status;
@@ -424,13 +412,9 @@ static int spi_gpio_probe(struct platform_device *pdev) 
			    SPI_CS_HIGH;

	master->flags = master_flags;

	master->bus_num = pdev->id;

	/* The master needs to think there is a chipselect even if not connected */

	master->num_chipselect = spi_gpio->has_cs ? pdata->num_chipselect : 1;

	master->setup = spi_gpio_setup;

	master->cleanup = spi_gpio_cleanup;

#ifdef CONFIG_OF

	master->dev.of_node = dev->of_node;

#endif



	bb = &spi_gpio->bitbang;

	bb->master = master;

	bb->chipselect = spi_gpio_chipselect;

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