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authorJan Kiszka <jan.kiszka@siemens.com>2017-05-22 12:43:18 +0200
committerJan Kiszka <jan.kiszka@siemens.com>2017-07-03 08:32:42 +0200
commit380b1e2f3a2f32bfe9c0aa85a68629eb99b043c0 (patch)
tree98ba961d67ef9bcba4c5762bdf6c623a573f4614 /drivers/gpio/gpio-exar.c
parent277036f05be242540b7bfe75f226107d04f51b06 (diff)
gpio-exar/8250-exar: Make set of exported GPIOs configurable
On the SIMATIC, IOT2040 only a single pin is exportable as GPIO, the rest is required to operate the UART. To allow modeling this case, expand the platform device data structure to specify a (consecutive) pin subset for exporting by the gpio-exar driver. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Diffstat (limited to 'drivers/gpio/gpio-exar.c')
-rw-r--r--drivers/gpio/gpio-exar.c56
1 files changed, 33 insertions, 23 deletions
diff --git a/drivers/gpio/gpio-exar.c b/drivers/gpio/gpio-exar.c
index 1a629831d45b..fb8d304cfa17 100644
--- a/drivers/gpio/gpio-exar.c
+++ b/drivers/gpio/gpio-exar.c
@@ -31,6 +31,7 @@ struct exar_gpio_chip {
int index;
void __iomem *regs;
char name[20];
+ unsigned int first_pin;
};
static void exar_update(struct gpio_chip *chip, unsigned int reg, int val,
@@ -51,11 +52,12 @@ static void exar_update(struct gpio_chip *chip, unsigned int reg, int val,
static int exar_set_direction(struct gpio_chip *chip, int direction,
unsigned int offset)
{
- unsigned int bank = offset / 8;
- unsigned int addr;
+ struct exar_gpio_chip *exar_gpio = gpiochip_get_data(chip);
+ unsigned int addr = (offset + exar_gpio->first_pin) / 8 ?
+ EXAR_OFFSET_MPIOSEL_HI : EXAR_OFFSET_MPIOSEL_LO;
+ unsigned int bit = (offset + exar_gpio->first_pin) % 8;
- addr = bank ? EXAR_OFFSET_MPIOSEL_HI : EXAR_OFFSET_MPIOSEL_LO;
- exar_update(chip, addr, direction, offset % 8);
+ exar_update(chip, addr, direction, bit);
return 0;
}
@@ -73,36 +75,33 @@ static int exar_get(struct gpio_chip *chip, unsigned int reg)
static int exar_get_direction(struct gpio_chip *chip, unsigned int offset)
{
- unsigned int bank = offset / 8;
- unsigned int addr;
- int val;
-
- addr = bank ? EXAR_OFFSET_MPIOSEL_HI : EXAR_OFFSET_MPIOSEL_LO;
- val = exar_get(chip, addr) & BIT(offset % 8);
+ struct exar_gpio_chip *exar_gpio = gpiochip_get_data(chip);
+ unsigned int addr = (offset + exar_gpio->first_pin) / 8 ?
+ EXAR_OFFSET_MPIOSEL_HI : EXAR_OFFSET_MPIOSEL_LO;
+ unsigned int bit = (offset + exar_gpio->first_pin) % 8;
- return !!val;
+ return !!(exar_get(chip, addr) & BIT(bit));
}
static int exar_get_value(struct gpio_chip *chip, unsigned int offset)
{
- unsigned int bank = offset / 8;
- unsigned int addr;
- int val;
-
- addr = bank ? EXAR_OFFSET_MPIOLVL_HI : EXAR_OFFSET_MPIOLVL_LO;
- val = exar_get(chip, addr) & BIT(offset % 8);
+ struct exar_gpio_chip *exar_gpio = gpiochip_get_data(chip);
+ unsigned int addr = (offset + exar_gpio->first_pin) / 8 ?
+ EXAR_OFFSET_MPIOLVL_HI : EXAR_OFFSET_MPIOLVL_LO;
+ unsigned int bit = (offset + exar_gpio->first_pin) % 8;
- return !!val;
+ return !!(exar_get(chip, addr) & BIT(bit));
}
static void exar_set_value(struct gpio_chip *chip, unsigned int offset,
int value)
{
- unsigned int bank = offset / 8;
- unsigned int addr;
+ struct exar_gpio_chip *exar_gpio = gpiochip_get_data(chip);
+ unsigned int addr = (offset + exar_gpio->first_pin) / 8 ?
+ EXAR_OFFSET_MPIOLVL_HI : EXAR_OFFSET_MPIOLVL_LO;
+ unsigned int bit = (offset + exar_gpio->first_pin) % 8;
- addr = bank ? EXAR_OFFSET_MPIOLVL_HI : EXAR_OFFSET_MPIOLVL_LO;
- exar_update(chip, addr, value, offset % 8);
+ exar_update(chip, addr, value, bit);
}
static int exar_direction_output(struct gpio_chip *chip, unsigned int offset,
@@ -121,6 +120,7 @@ static int gpio_exar_probe(struct platform_device *pdev)
{
struct pci_dev *pcidev = to_pci_dev(pdev->dev.parent);
struct exar_gpio_chip *exar_gpio;
+ u32 first_pin, ngpios;
void __iomem *p;
int index, ret;
@@ -132,6 +132,15 @@ static int gpio_exar_probe(struct platform_device *pdev)
if (!p)
return -ENOMEM;
+ ret = device_property_read_u32(&pdev->dev, "linux,first-pin",
+ &first_pin);
+ if (ret)
+ return ret;
+
+ ret = device_property_read_u32(&pdev->dev, "ngpios", &ngpios);
+ if (ret)
+ return ret;
+
exar_gpio = devm_kzalloc(&pdev->dev, sizeof(*exar_gpio), GFP_KERNEL);
if (!exar_gpio)
return -ENOMEM;
@@ -149,9 +158,10 @@ static int gpio_exar_probe(struct platform_device *pdev)
exar_gpio->gpio_chip.get = exar_get_value;
exar_gpio->gpio_chip.set = exar_set_value;
exar_gpio->gpio_chip.base = -1;
- exar_gpio->gpio_chip.ngpio = 16;
+ exar_gpio->gpio_chip.ngpio = ngpios;
exar_gpio->regs = p;
exar_gpio->index = index;
+ exar_gpio->first_pin = first_pin;
ret = devm_gpiochip_add_data(&pdev->dev,
&exar_gpio->gpio_chip, exar_gpio);