spi: s3c24xx: Convert to GPIO descriptors

This driver has a bunch of custom oldstyle GPIO number-passing
fields and a custom set-up callback.

The good thing is: nothing in the kernel is using it.

Convert the driver to use GPIO descriptors with a SPI_MASTER_GPIO_SS
flag so that the local CS callback also get invoked as the hardware
needs this.

New users of this driver can provide GPIO descriptor tables like
the other converted drivers.

Cc: linux-samsung-soc@vger.kernel.org
Cc: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Cc: Sylwester Nawrocki <snawrocki@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Link: https://lore.kernel.org/r/20220119000914.192553-1-linus.walleij@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
This commit is contained in:
Linus Walleij 2022-01-19 01:09:14 +01:00 committed by Mark Brown
parent a45cf3cc72
commit 7f2a3cf4e6
No known key found for this signature in database
GPG key ID: 24D68B725D5487D0
2 changed files with 3 additions and 49 deletions

View file

@ -12,7 +12,6 @@
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/platform_device.h>
#include <linux/gpio.h>
#include <linux/io.h>
#include <linux/slab.h>
@ -62,9 +61,6 @@ struct s3c24xx_spi {
unsigned char fiq_inuse;
unsigned char fiq_claimed;
void (*set_cs)(struct s3c2410_spi_info *spi,
int cs, int pol);
/* data buffers */
const unsigned char *tx;
unsigned char *rx;
@ -84,29 +80,21 @@ static inline struct s3c24xx_spi *to_hw(struct spi_device *sdev)
return spi_master_get_devdata(sdev->master);
}
static void s3c24xx_spi_gpiocs(struct s3c2410_spi_info *spi, int cs, int pol)
{
gpio_set_value(spi->pin_cs, pol);
}
static void s3c24xx_spi_chipsel(struct spi_device *spi, int value)
{
struct s3c24xx_spi_devstate *cs = spi->controller_state;
struct s3c24xx_spi *hw = to_hw(spi);
unsigned int cspol = spi->mode & SPI_CS_HIGH ? 1 : 0;
/* change the chipselect state and the state of the spi engine clock */
switch (value) {
case BITBANG_CS_INACTIVE:
hw->set_cs(hw->pdata, spi->chip_select, cspol^1);
writeb(cs->spcon, hw->regs + S3C2410_SPCON);
break;
case BITBANG_CS_ACTIVE:
writeb(cs->spcon | S3C2410_SPCON_ENSCK,
hw->regs + S3C2410_SPCON);
hw->set_cs(hw->pdata, spi->chip_select, cspol);
break;
}
}
@ -452,14 +440,6 @@ static void s3c24xx_spi_initialsetup(struct s3c24xx_spi *hw)
writeb(0xff, hw->regs + S3C2410_SPPRE);
writeb(SPPIN_DEFAULT, hw->regs + S3C2410_SPPIN);
writeb(SPCON_DEFAULT, hw->regs + S3C2410_SPCON);
if (hw->pdata) {
if (hw->set_cs == s3c24xx_spi_gpiocs)
gpio_direction_output(hw->pdata->pin_cs, 1);
if (hw->pdata->gpio_setup)
hw->pdata->gpio_setup(hw->pdata, 1);
}
}
static int s3c24xx_spi_probe(struct platform_device *pdev)
@ -502,6 +482,9 @@ static int s3c24xx_spi_probe(struct platform_device *pdev)
master->num_chipselect = hw->pdata->num_cs;
master->bus_num = pdata->bus_num;
master->bits_per_word_mask = SPI_BPW_MASK(8);
/* we need to call the local chipselect callback */
master->flags = SPI_MASTER_GPIO_SS;
master->use_gpio_descriptors = true;
/* setup the state for the bitbang driver */
@ -541,27 +524,6 @@ static int s3c24xx_spi_probe(struct platform_device *pdev)
goto err_no_pdata;
}
/* setup any gpio we can */
if (!pdata->set_cs) {
if (pdata->pin_cs < 0) {
dev_err(&pdev->dev, "No chipselect pin\n");
err = -EINVAL;
goto err_register;
}
err = devm_gpio_request(&pdev->dev, pdata->pin_cs,
dev_name(&pdev->dev));
if (err) {
dev_err(&pdev->dev, "Failed to get gpio for cs\n");
goto err_register;
}
hw->set_cs = s3c24xx_spi_gpiocs;
gpio_direction_output(pdata->pin_cs, 1);
} else
hw->set_cs = pdata->set_cs;
s3c24xx_spi_initialsetup(hw);
/* register our spi controller */
@ -604,9 +566,6 @@ static int s3c24xx_spi_suspend(struct device *dev)
if (ret)
return ret;
if (hw->pdata && hw->pdata->gpio_setup)
hw->pdata->gpio_setup(hw->pdata, 0);
clk_disable(hw->clk);
return 0;
}

View file

@ -10,14 +10,9 @@
#define __LINUX_SPI_S3C24XX_H __FILE__
struct s3c2410_spi_info {
int pin_cs; /* simple gpio cs */
unsigned int num_cs; /* total chipselects */
int bus_num; /* bus number to use. */
unsigned int use_fiq:1; /* use fiq */
void (*gpio_setup)(struct s3c2410_spi_info *spi, int enable);
void (*set_cs)(struct s3c2410_spi_info *spi, int cs, int pol);
};
extern int s3c24xx_set_fiq(unsigned int irq, u32 *ack_ptr, bool on);