| /* |
| * AppliedMicro X-Gene SoC GPIO Driver |
| * |
| * Copyright (c) 2014, Applied Micro Circuits Corporation |
| * Author: Feng Kan <fkan@apm.com>. |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program. If not, see <http://www.gnu.org/licenses/>. |
| */ |
| |
| #include <linux/module.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 xgene_gpio { |
| struct gpio_chip chip; |
| void __iomem *base; |
| spinlock_t lock; |
| #ifdef CONFIG_PM |
| u32 set_dr_val[XGENE_MAX_GPIO_BANKS]; |
| #endif |
| }; |
| |
| static inline struct xgene_gpio *to_xgene_gpio(struct gpio_chip *chip) |
| { |
| return container_of(chip, struct xgene_gpio, chip); |
| } |
| |
| static int xgene_gpio_get(struct gpio_chip *gc, unsigned int offset) |
| { |
| struct xgene_gpio *chip = to_xgene_gpio(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 = to_xgene_gpio(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 = to_xgene_gpio(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_dir_in(struct gpio_chip *gc, unsigned int offset) |
| { |
| struct xgene_gpio *chip = to_xgene_gpio(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 = to_xgene_gpio(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; |
| } |
| |
| #ifdef CONFIG_PM |
| static 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 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); |
| #define XGENE_GPIO_PM_OPS (&xgene_gpio_pm) |
| #else |
| #define XGENE_GPIO_PM_OPS NULL |
| #endif |
| |
| static int xgene_gpio_probe(struct platform_device *pdev) |
| { |
| struct resource *res; |
| struct xgene_gpio *gpio; |
| int err = 0; |
| |
| gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL); |
| if (!gpio) { |
| err = -ENOMEM; |
| goto err; |
| } |
| |
| res = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| gpio->base = devm_ioremap_nocache(&pdev->dev, res->start, |
| resource_size(res)); |
| if (IS_ERR(gpio->base)) { |
| err = PTR_ERR(gpio->base); |
| goto err; |
| } |
| |
| gpio->chip.ngpio = XGENE_MAX_GPIOS; |
| |
| gpio->chip.dev = &pdev->dev; |
| 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); |
| |
| err = gpiochip_add(&gpio->chip); |
| if (err) { |
| dev_err(&pdev->dev, |
| "failed to register gpiochip.\n"); |
| goto err; |
| } |
| |
| dev_info(&pdev->dev, "X-Gene GPIO driver registered.\n"); |
| return 0; |
| err: |
| dev_err(&pdev->dev, "X-Gene GPIO driver registration failed.\n"); |
| return err; |
| } |
| |
| static int xgene_gpio_remove(struct platform_device *pdev) |
| { |
| struct xgene_gpio *gpio = platform_get_drvdata(pdev); |
| |
| gpiochip_remove(&gpio->chip); |
| return 0; |
| } |
| |
| #ifdef CONFIG_OF |
| static const struct of_device_id xgene_gpio_of_match[] = { |
| { .compatible = "apm,xgene-gpio", }, |
| {}, |
| }; |
| MODULE_DEVICE_TABLE(of, xgene_gpio_of_match); |
| #endif |
| |
| static struct platform_driver xgene_gpio_driver = { |
| .driver = { |
| .name = "xgene-gpio", |
| .owner = THIS_MODULE, |
| .of_match_table = xgene_gpio_of_match, |
| .pm = XGENE_GPIO_PM_OPS, |
| }, |
| .probe = xgene_gpio_probe, |
| .remove = xgene_gpio_remove, |
| }; |
| |
| module_platform_driver(xgene_gpio_driver); |
| |
| MODULE_AUTHOR("Feng Kan <fkan@apm.com>"); |
| MODULE_DESCRIPTION("APM X-Gene GPIO driver"); |
| MODULE_LICENSE("GPL"); |