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path: root/drivers/gpio/gpio-xgene.c
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Diffstat (limited to 'drivers/gpio/gpio-xgene.c')
-rw-r--r--drivers/gpio/gpio-xgene.c209
1 files changed, 209 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-xgene.c b/drivers/gpio/gpio-xgene.c
new file mode 100644
index 000000000..fb4b0c67a
--- /dev/null
+++ b/drivers/gpio/gpio-xgene.c
@@ -0,0 +1,209 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * AppliedMicro X-Gene SoC GPIO Driver
+ *
+ * Copyright (c) 2014, Applied Micro Circuits Corporation
+ * Author: Feng Kan <fkan@apm.com>.
+ */
+
+#include <linux/acpi.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/spinlock.h>
+#include <linux/platform_device.h>
+#include <linux/gpio/driver.h>
+#include <linux/types.h>
+#include <linux/bitops.h>
+
+#define GPIO_SET_DR_OFFSET 0x0C
+#define GPIO_DATA_OFFSET 0x14
+#define GPIO_BANK_STRIDE 0x0C
+
+#define XGENE_GPIOS_PER_BANK 16
+#define XGENE_MAX_GPIO_BANKS 3
+#define XGENE_MAX_GPIOS (XGENE_GPIOS_PER_BANK * XGENE_MAX_GPIO_BANKS)
+
+#define GPIO_BIT_OFFSET(x) (x % XGENE_GPIOS_PER_BANK)
+#define GPIO_BANK_OFFSET(x) ((x / XGENE_GPIOS_PER_BANK) * GPIO_BANK_STRIDE)
+
+struct xgene_gpio {
+ struct gpio_chip chip;
+ void __iomem *base;
+ spinlock_t lock;
+ u32 set_dr_val[XGENE_MAX_GPIO_BANKS];
+};
+
+static int xgene_gpio_get(struct gpio_chip *gc, unsigned int offset)
+{
+ struct xgene_gpio *chip = gpiochip_get_data(gc);
+ unsigned long bank_offset;
+ u32 bit_offset;
+
+ bank_offset = GPIO_DATA_OFFSET + GPIO_BANK_OFFSET(offset);
+ bit_offset = GPIO_BIT_OFFSET(offset);
+ return !!(ioread32(chip->base + bank_offset) & BIT(bit_offset));
+}
+
+static void __xgene_gpio_set(struct gpio_chip *gc, unsigned int offset, int val)
+{
+ struct xgene_gpio *chip = gpiochip_get_data(gc);
+ unsigned long bank_offset;
+ u32 setval, bit_offset;
+
+ bank_offset = GPIO_SET_DR_OFFSET + GPIO_BANK_OFFSET(offset);
+ bit_offset = GPIO_BIT_OFFSET(offset) + XGENE_GPIOS_PER_BANK;
+
+ setval = ioread32(chip->base + bank_offset);
+ if (val)
+ setval |= BIT(bit_offset);
+ else
+ setval &= ~BIT(bit_offset);
+ iowrite32(setval, chip->base + bank_offset);
+}
+
+static void xgene_gpio_set(struct gpio_chip *gc, unsigned int offset, int val)
+{
+ struct xgene_gpio *chip = gpiochip_get_data(gc);
+ unsigned long flags;
+
+ spin_lock_irqsave(&chip->lock, flags);
+ __xgene_gpio_set(gc, offset, val);
+ spin_unlock_irqrestore(&chip->lock, flags);
+}
+
+static int xgene_gpio_get_direction(struct gpio_chip *gc, unsigned int offset)
+{
+ struct xgene_gpio *chip = gpiochip_get_data(gc);
+ unsigned long bank_offset, bit_offset;
+
+ bank_offset = GPIO_SET_DR_OFFSET + GPIO_BANK_OFFSET(offset);
+ bit_offset = GPIO_BIT_OFFSET(offset);
+
+ if (ioread32(chip->base + bank_offset) & BIT(bit_offset))
+ return GPIO_LINE_DIRECTION_IN;
+
+ return GPIO_LINE_DIRECTION_OUT;
+}
+
+static int xgene_gpio_dir_in(struct gpio_chip *gc, unsigned int offset)
+{
+ struct xgene_gpio *chip = gpiochip_get_data(gc);
+ unsigned long flags, bank_offset;
+ u32 dirval, bit_offset;
+
+ bank_offset = GPIO_SET_DR_OFFSET + GPIO_BANK_OFFSET(offset);
+ bit_offset = GPIO_BIT_OFFSET(offset);
+
+ spin_lock_irqsave(&chip->lock, flags);
+
+ dirval = ioread32(chip->base + bank_offset);
+ dirval |= BIT(bit_offset);
+ iowrite32(dirval, chip->base + bank_offset);
+
+ spin_unlock_irqrestore(&chip->lock, flags);
+
+ return 0;
+}
+
+static int xgene_gpio_dir_out(struct gpio_chip *gc,
+ unsigned int offset, int val)
+{
+ struct xgene_gpio *chip = gpiochip_get_data(gc);
+ unsigned long flags, bank_offset;
+ u32 dirval, bit_offset;
+
+ bank_offset = GPIO_SET_DR_OFFSET + GPIO_BANK_OFFSET(offset);
+ bit_offset = GPIO_BIT_OFFSET(offset);
+
+ spin_lock_irqsave(&chip->lock, flags);
+
+ dirval = ioread32(chip->base + bank_offset);
+ dirval &= ~BIT(bit_offset);
+ iowrite32(dirval, chip->base + bank_offset);
+ __xgene_gpio_set(gc, offset, val);
+
+ spin_unlock_irqrestore(&chip->lock, flags);
+
+ return 0;
+}
+
+static __maybe_unused int xgene_gpio_suspend(struct device *dev)
+{
+ struct xgene_gpio *gpio = dev_get_drvdata(dev);
+ unsigned long bank_offset;
+ unsigned int bank;
+
+ for (bank = 0; bank < XGENE_MAX_GPIO_BANKS; bank++) {
+ bank_offset = GPIO_SET_DR_OFFSET + bank * GPIO_BANK_STRIDE;
+ gpio->set_dr_val[bank] = ioread32(gpio->base + bank_offset);
+ }
+ return 0;
+}
+
+static __maybe_unused int xgene_gpio_resume(struct device *dev)
+{
+ struct xgene_gpio *gpio = dev_get_drvdata(dev);
+ unsigned long bank_offset;
+ unsigned int bank;
+
+ for (bank = 0; bank < XGENE_MAX_GPIO_BANKS; bank++) {
+ bank_offset = GPIO_SET_DR_OFFSET + bank * GPIO_BANK_STRIDE;
+ iowrite32(gpio->set_dr_val[bank], gpio->base + bank_offset);
+ }
+ return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(xgene_gpio_pm, xgene_gpio_suspend, xgene_gpio_resume);
+
+static int xgene_gpio_probe(struct platform_device *pdev)
+{
+ struct xgene_gpio *gpio;
+
+ gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
+ if (!gpio)
+ return -ENOMEM;
+
+ gpio->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(gpio->base))
+ return PTR_ERR(gpio->base);
+
+ gpio->chip.ngpio = XGENE_MAX_GPIOS;
+
+ spin_lock_init(&gpio->lock);
+ gpio->chip.parent = &pdev->dev;
+ gpio->chip.get_direction = xgene_gpio_get_direction;
+ gpio->chip.direction_input = xgene_gpio_dir_in;
+ gpio->chip.direction_output = xgene_gpio_dir_out;
+ gpio->chip.get = xgene_gpio_get;
+ gpio->chip.set = xgene_gpio_set;
+ gpio->chip.label = dev_name(&pdev->dev);
+ gpio->chip.base = -1;
+
+ platform_set_drvdata(pdev, gpio);
+
+ return devm_gpiochip_add_data(&pdev->dev, &gpio->chip, gpio);
+}
+
+static const struct of_device_id xgene_gpio_of_match[] = {
+ { .compatible = "apm,xgene-gpio", },
+ {},
+};
+
+#ifdef CONFIG_ACPI
+static const struct acpi_device_id xgene_gpio_acpi_match[] = {
+ { "APMC0D14", 0 },
+ { },
+};
+#endif
+
+static struct platform_driver xgene_gpio_driver = {
+ .driver = {
+ .name = "xgene-gpio",
+ .of_match_table = xgene_gpio_of_match,
+ .acpi_match_table = ACPI_PTR(xgene_gpio_acpi_match),
+ .pm = &xgene_gpio_pm,
+ },
+ .probe = xgene_gpio_probe,
+};
+builtin_platform_driver(xgene_gpio_driver);