[PATCH v5 10/11] gpio-exar/8250-exar: Make set of exported GPIOs configurable
From: Jan Kiszka
Date: Fri Jun 02 2017 - 03:30:02 EST
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@xxxxxxxxxxx>
Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
---
drivers/gpio/gpio-exar.c | 52 +++++++++++++++++++++----------------
drivers/tty/serial/8250/8250_exar.c | 15 ++++++++---
2 files changed, 41 insertions(+), 26 deletions(-)
diff --git a/drivers/gpio/gpio-exar.c b/drivers/gpio/gpio-exar.c
index 1a629831d45b..220e93ed9111 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 +132,11 @@ static int gpio_exar_probe(struct platform_device *pdev)
if (!p)
return -ENOMEM;
+ if (device_property_read_u32(&pdev->dev, "gpio-exar,first-pin",
+ &first_pin) < 0 ||
+ device_property_read_u32(&pdev->dev, "ngpios", &ngpios) < 0)
+ return -EINVAL;
+
exar_gpio = devm_kzalloc(&pdev->dev, sizeof(*exar_gpio), GFP_KERNEL);
if (!exar_gpio)
return -ENOMEM;
@@ -149,9 +154,10 @@ 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);
diff --git a/drivers/tty/serial/8250/8250_exar.c b/drivers/tty/serial/8250/8250_exar.c
index 1106f1f58c77..bd0e40e869b8 100644
--- a/drivers/tty/serial/8250/8250_exar.c
+++ b/drivers/tty/serial/8250/8250_exar.c
@@ -14,6 +14,7 @@
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
+#include <linux/property.h>
#include <linux/serial_core.h>
#include <linux/serial_reg.h>
#include <linux/slab.h>
@@ -201,7 +202,8 @@ static void setup_gpio(struct pci_dev *pcidev, u8 __iomem *p)
}
static void *
-__xr17v35x_register_gpio(struct pci_dev *pcidev)
+__xr17v35x_register_gpio(struct pci_dev *pcidev,
+ const struct property_entry *properties)
{
struct platform_device *pdev;
@@ -212,7 +214,8 @@ __xr17v35x_register_gpio(struct pci_dev *pcidev)
pdev->dev.parent = &pcidev->dev;
ACPI_COMPANION_SET(&pdev->dev, ACPI_COMPANION(&pcidev->dev));
- if (platform_device_add(pdev) < 0) {
+ if (platform_device_add_properties(pdev, properties) < 0 ||
+ platform_device_add(pdev) < 0) {
platform_device_put(pdev);
return NULL;
}
@@ -220,12 +223,18 @@ __xr17v35x_register_gpio(struct pci_dev *pcidev)
return pdev;
}
+static const struct property_entry exar_gpio_properties[] = {
+ PROPERTY_ENTRY_U32("gpio-exar,first-pin", 0),
+ PROPERTY_ENTRY_U32("ngpios", 16),
+ { }
+};
+
static int xr17v35x_register_gpio(struct pci_dev *pcidev,
struct uart_8250_port *port)
{
if (pcidev->vendor == PCI_VENDOR_ID_EXAR)
port->port.private_data =
- __xr17v35x_register_gpio(pcidev);
+ __xr17v35x_register_gpio(pcidev, exar_gpio_properties);
return 0;
}
--
2.12.3