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

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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: Andrey 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: Mark Brown <broonie@kernel.org>
This commit is contained in:
Andrey Smirnov 2019-04-02 21:01:27 -07:00 committed by Mark Brown
parent d9088966c8
commit 249e2632dc
No known key found for this signature in database
GPG key ID: 24D68B725D5487D0
1 changed files with 60 additions and 76 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

126
drivers/spi/spi-gpio.c
View file

@ -46,7 +46,6 @@ struct spi_gpio {
struct gpio_desc *miso; struct gpio_desc *miso;
struct gpio_desc *mosi; struct gpio_desc *mosi;
struct gpio_desc **cs_gpios; 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); gpiod_set_value_cansleep(spi_gpio->sck, spi->mode & SPI_CPOL);
/* Drive chip select line, if we have one */ /* 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]; struct gpio_desc *cs = spi_gpio->cs_gpios[spi->chip_select];
/* SPI chip selects are normally active-low */ /* 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 * The CS GPIOs have already been
* initialized from the descriptor lookup. * initialized from the descriptor lookup.
*/ */
if (spi_gpio->cs_gpios) {
cs = spi_gpio->cs_gpios[spi->chip_select]; cs = spi_gpio->cs_gpios[spi->chip_select];
if (!spi->controller_state && cs) if (!spi->controller_state && cs)
status = gpiod_direction_output(cs, status = gpiod_direction_output(cs,
!(spi->mode & SPI_CS_HIGH)); !(spi->mode & SPI_CS_HIGH));
}
if (!status) if (!status)
status = spi_bitbang_setup(spi); 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, static int spi_gpio_request(struct device *dev,
struct spi_gpio *spi_gpio, struct spi_gpio *spi_gpio,
unsigned int num_chipselects,
u16 *mflags) u16 *mflags)
{ {
int i;
spi_gpio->mosi = devm_gpiod_get_optional(dev, "mosi", GPIOD_OUT_LOW); spi_gpio->mosi = devm_gpiod_get_optional(dev, "mosi", GPIOD_OUT_LOW);
if (IS_ERR(spi_gpio->mosi)) if (IS_ERR(spi_gpio->mosi))
return PTR_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)) if (IS_ERR(spi_gpio->sck))
return PTR_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; return 0;
} }
@ -332,90 +323,87 @@ static const struct of_device_id spi_gpio_dt_ids[] = {
}; };
MODULE_DEVICE_TABLE(of, 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; master->dev.of_node = pdev->dev.of_node;
u32 tmp; master->use_gpio_descriptors = true;
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);
if (!of_id)
return 0; 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;
}
pdata->num_chipselect = tmp;
pdev->dev.platform_data = pdata;
return 1;
error_free:
devm_kfree(&pdev->dev, pdata);
return ret;
} }
#else #else
static inline int spi_gpio_probe_dt(struct platform_device *pdev) static inline int spi_gpio_probe_dt(struct platform_device *pdev,
struct spi_master *master)
{ {
return 0; return 0;
} }
#endif #endif
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;
#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;
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]);
}
return 0;
}
static int spi_gpio_probe(struct platform_device *pdev) static int spi_gpio_probe(struct platform_device *pdev)
{ {
int status; int status;
struct spi_master *master; struct spi_master *master;
struct spi_gpio *spi_gpio; struct spi_gpio *spi_gpio;
struct spi_gpio_platform_data *pdata;
struct device *dev = &pdev->dev; struct device *dev = &pdev->dev;
struct spi_bitbang *bb; struct spi_bitbang *bb;
const struct of_device_id *of_id;
u16 master_flags = 0; u16 master_flags = 0;
bool use_of = 0;
status = spi_gpio_probe_dt(pdev); of_id = of_match_device(spi_gpio_dt_ids, &pdev->dev);
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
master = spi_alloc_master(dev, sizeof(*spi_gpio)); master = spi_alloc_master(dev, sizeof(*spi_gpio));
if (!master) if (!master)
return -ENOMEM; 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, if (status)
pdata->num_chipselect, return status;
sizeof(*spi_gpio->cs_gpios),
GFP_KERNEL); spi_gpio = spi_master_get_devdata(master);
if (!spi_gpio->cs_gpios)
return -ENOMEM;
platform_set_drvdata(pdev, spi_gpio); platform_set_drvdata(pdev, spi_gpio);
/* Determine if we have chip selects connected */
spi_gpio->has_cs = !!pdata->num_chipselect;
spi_gpio->pdev = pdev; spi_gpio->pdev = pdev;
status = spi_gpio_request(dev, spi_gpio, status = spi_gpio_request(dev, spi_gpio, &master_flags);
pdata->num_chipselect, &master_flags);
if (status) if (status)
return status; return status;
@ -424,13 +412,9 @@ static int spi_gpio_probe(struct platform_device *pdev)
SPI_CS_HIGH; SPI_CS_HIGH;
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 */
master->num_chipselect = spi_gpio->has_cs ? pdata->num_chipselect : 1;
master->setup = spi_gpio_setup; master->setup = spi_gpio_setup;
master->cleanup = spi_gpio_cleanup; master->cleanup = spi_gpio_cleanup;
#ifdef CONFIG_OF
master->dev.of_node = dev->of_node;
#endif
bb = &spi_gpio->bitbang; bb = &spi_gpio->bitbang;
bb->master = master; bb->master = master;
bb->chipselect = spi_gpio_chipselect; bb->chipselect = spi_gpio_chipselect;