*
* Copyright (C) 2015 Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
*/
+
#include <linux/bitops.h>
#include <linux/device.h>
#include <linux/gpio/driver.h>
+#include <linux/idr.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/platform_device.h>
+#include <linux/regmap.h>
#define EXAR_OFFSET_MPIOLVL_LO 0x90
#define EXAR_OFFSET_MPIOSEL_LO 0x93
struct exar_gpio_chip {
struct gpio_chip gpio_chip;
- struct mutex lock;
+ struct regmap *regmap;
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,
- unsigned int offset)
+static unsigned int
+exar_offset_to_sel_addr(struct exar_gpio_chip *exar_gpio, unsigned int offset)
{
- struct exar_gpio_chip *exar_gpio = gpiochip_get_data(chip);
- int temp;
-
- mutex_lock(&exar_gpio->lock);
- temp = readb(exar_gpio->regs + reg);
- temp &= ~BIT(offset);
- if (val)
- temp |= BIT(offset);
- writeb(temp, exar_gpio->regs + reg);
- mutex_unlock(&exar_gpio->lock);
+ return (offset + exar_gpio->first_pin) / 8 ? EXAR_OFFSET_MPIOSEL_HI
+ : EXAR_OFFSET_MPIOSEL_LO;
}
-static int exar_set_direction(struct gpio_chip *chip, int direction,
- unsigned int offset)
+static unsigned int
+exar_offset_to_lvl_addr(struct exar_gpio_chip *exar_gpio, unsigned int offset)
{
- 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;
-
- exar_update(chip, addr, direction, bit);
- return 0;
+ return (offset + exar_gpio->first_pin) / 8 ? EXAR_OFFSET_MPIOLVL_HI
+ : EXAR_OFFSET_MPIOLVL_LO;
}
-static int exar_get(struct gpio_chip *chip, unsigned int reg)
+static unsigned int
+exar_offset_to_bit(struct exar_gpio_chip *exar_gpio, unsigned int offset)
{
- struct exar_gpio_chip *exar_gpio = gpiochip_get_data(chip);
- int value;
-
- mutex_lock(&exar_gpio->lock);
- value = readb(exar_gpio->regs + reg);
- mutex_unlock(&exar_gpio->lock);
-
- return value;
+ return (offset + exar_gpio->first_pin) % 8;
}
static int exar_get_direction(struct gpio_chip *chip, unsigned int offset)
{
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;
+ unsigned int addr = exar_offset_to_sel_addr(exar_gpio, offset);
+ unsigned int bit = exar_offset_to_bit(exar_gpio, offset);
- if (exar_get(chip, addr) & BIT(bit))
+ if (regmap_test_bits(exar_gpio->regmap, addr, BIT(bit)))
return GPIO_LINE_DIRECTION_IN;
return GPIO_LINE_DIRECTION_OUT;
static int exar_get_value(struct gpio_chip *chip, unsigned int offset)
{
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;
+ unsigned int addr = exar_offset_to_lvl_addr(exar_gpio, offset);
+ unsigned int bit = exar_offset_to_bit(exar_gpio, offset);
- return !!(exar_get(chip, addr) & BIT(bit));
+ return !!(regmap_test_bits(exar_gpio->regmap, addr, BIT(bit)));
}
static void exar_set_value(struct gpio_chip *chip, unsigned int offset,
int value)
{
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;
+ unsigned int addr = exar_offset_to_lvl_addr(exar_gpio, offset);
+ unsigned int bit = exar_offset_to_bit(exar_gpio, offset);
- exar_update(chip, addr, value, bit);
+ if (value)
+ regmap_set_bits(exar_gpio->regmap, addr, BIT(bit));
+ else
+ regmap_clear_bits(exar_gpio->regmap, addr, BIT(bit));
}
static int exar_direction_output(struct gpio_chip *chip, unsigned int offset,
int value)
{
+ struct exar_gpio_chip *exar_gpio = gpiochip_get_data(chip);
+ unsigned int addr = exar_offset_to_sel_addr(exar_gpio, offset);
+ unsigned int bit = exar_offset_to_bit(exar_gpio, offset);
+
exar_set_value(chip, offset, value);
- return exar_set_direction(chip, 0, offset);
+ regmap_clear_bits(exar_gpio->regmap, addr, BIT(bit));
+
+ return 0;
}
static int exar_direction_input(struct gpio_chip *chip, unsigned int offset)
{
- return exar_set_direction(chip, 1, offset);
+ struct exar_gpio_chip *exar_gpio = gpiochip_get_data(chip);
+ unsigned int addr = exar_offset_to_sel_addr(exar_gpio, offset);
+ unsigned int bit = exar_offset_to_bit(exar_gpio, offset);
+
+ regmap_set_bits(exar_gpio->regmap, addr, BIT(bit));
+
+ return 0;
}
+static void exar_devm_ida_free(void *data)
+{
+ struct exar_gpio_chip *exar_gpio = data;
+
+ ida_free(&ida_index, exar_gpio->index);
+}
+
+static const struct regmap_config exar_regmap_config = {
+ .name = "exar-gpio",
+ .reg_bits = 16,
+ .val_bits = 8,
+};
+
static int gpio_exar_probe(struct platform_device *pdev)
{
- struct pci_dev *pcidev = to_pci_dev(pdev->dev.parent);
+ struct device *dev = &pdev->dev;
+ struct pci_dev *pcidev = to_pci_dev(dev->parent);
struct exar_gpio_chip *exar_gpio;
u32 first_pin, ngpios;
void __iomem *p;
if (!p)
return -ENOMEM;
- ret = device_property_read_u32(&pdev->dev, "exar,first-pin",
- &first_pin);
+ ret = device_property_read_u32(dev, "exar,first-pin", &first_pin);
if (ret)
return ret;
- ret = device_property_read_u32(&pdev->dev, "ngpios", &ngpios);
+ ret = device_property_read_u32(dev, "ngpios", &ngpios);
if (ret)
return ret;
- exar_gpio = devm_kzalloc(&pdev->dev, sizeof(*exar_gpio), GFP_KERNEL);
+ exar_gpio = devm_kzalloc(dev, sizeof(*exar_gpio), GFP_KERNEL);
if (!exar_gpio)
return -ENOMEM;
- mutex_init(&exar_gpio->lock);
+ /*
+ * We don't need to check the return values of mmio regmap operations (unless
+ * the regmap has a clock attached which is not the case here).
+ */
+ exar_gpio->regmap = devm_regmap_init_mmio(dev, p, &exar_regmap_config);
+ if (IS_ERR(exar_gpio->regmap))
+ return PTR_ERR(exar_gpio->regmap);
+
+ index = ida_alloc(&ida_index, GFP_KERNEL);
+ if (index < 0)
+ return index;
- index = ida_simple_get(&ida_index, 0, 0, GFP_KERNEL);
- if (index < 0) {
- ret = index;
- goto err_mutex_destroy;
- }
+ ret = devm_add_action_or_reset(dev, exar_devm_ida_free, exar_gpio);
+ if (ret)
+ return ret;
sprintf(exar_gpio->name, "exar_gpio%d", index);
exar_gpio->gpio_chip.label = exar_gpio->name;
- exar_gpio->gpio_chip.parent = &pdev->dev;
+ exar_gpio->gpio_chip.parent = dev;
exar_gpio->gpio_chip.direction_output = exar_direction_output;
exar_gpio->gpio_chip.direction_input = exar_direction_input;
exar_gpio->gpio_chip.get_direction = exar_get_direction;
exar_gpio->gpio_chip.set = exar_set_value;
exar_gpio->gpio_chip.base = -1;
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);
+ ret = devm_gpiochip_add_data(dev, &exar_gpio->gpio_chip, exar_gpio);
if (ret)
- goto err_destroy;
+ return ret;
platform_set_drvdata(pdev, exar_gpio);
- return 0;
-
-err_destroy:
- ida_simple_remove(&ida_index, index);
-err_mutex_destroy:
- mutex_destroy(&exar_gpio->lock);
- return ret;
-}
-
-static int gpio_exar_remove(struct platform_device *pdev)
-{
- struct exar_gpio_chip *exar_gpio = platform_get_drvdata(pdev);
-
- ida_simple_remove(&ida_index, exar_gpio->index);
- mutex_destroy(&exar_gpio->lock);
-
return 0;
}
static struct platform_driver gpio_exar_driver = {
.probe = gpio_exar_probe,
- .remove = gpio_exar_remove,
.driver = {
.name = DRIVER_NAME,
},
projects / linux-2.6-microblaze.git / blobdiff