/* * Copyright (C) 2012-2014 Broadcom Corporation * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation version 2. * * This program is distributed "as is" WITHOUT ANY WARRANTY of any * kind, whether express or implied; without even the implied warranty * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. */ #include <linux/bitops.h> #include <linux/err.h> #include <linux/io.h> #include <linux/gpio.h> #include <linux/of_device.h> #include <linux/of_irq.h> #include <linux/module.h> #include <linux/irqdomain.h> #include <linux/irqchip/chained_irq.h> #define BCM_GPIO_PASSWD 0x00a5a501 #define GPIO_PER_BANK 32 #define GPIO_MAX_BANK_NUM 8 #define GPIO_BANK(gpio) ((gpio) >> 5) #define GPIO_BIT(gpio) ((gpio) & (GPIO_PER_BANK - 1)) #define GPIO_OUT_STATUS(bank) (0x00000000 + ((bank) << 2)) #define GPIO_IN_STATUS(bank) (0x00000020 + ((bank) << 2)) #define GPIO_OUT_SET(bank) (0x00000040 + ((bank) << 2)) #define GPIO_OUT_CLEAR(bank) (0x00000060 + ((bank) << 2)) #define GPIO_INT_STATUS(bank) (0x00000080 + ((bank) << 2)) #define GPIO_INT_MASK(bank) (0x000000a0 + ((bank) << 2)) #define GPIO_INT_MSKCLR(bank) (0x000000c0 + ((bank) << 2)) #define GPIO_CONTROL(bank) (0x00000100 + ((bank) << 2)) #define GPIO_PWD_STATUS(bank) (0x00000500 + ((bank) << 2)) #define GPIO_GPPWR_OFFSET 0x00000520 #define GPIO_GPCTR0_DBR_SHIFT 5 #define GPIO_GPCTR0_DBR_MASK 0x000001e0 #define GPIO_GPCTR0_ITR_SHIFT 3 #define GPIO_GPCTR0_ITR_MASK 0x00000018 #define GPIO_GPCTR0_ITR_CMD_RISING_EDGE 0x00000001 #define GPIO_GPCTR0_ITR_CMD_FALLING_EDGE 0x00000002 #define GPIO_GPCTR0_ITR_CMD_BOTH_EDGE 0x00000003 #define GPIO_GPCTR0_IOTR_MASK 0x00000001 #define GPIO_GPCTR0_IOTR_CMD_0UTPUT 0x00000000 #define GPIO_GPCTR0_IOTR_CMD_INPUT 0x00000001 #define GPIO_GPCTR0_DB_ENABLE_MASK 0x00000100 #define LOCK_CODE 0xffffffff #define UNLOCK_CODE 0x00000000 struct bcm_kona_gpio { void __iomem *reg_base; int num_bank; spinlock_t lock; struct gpio_chip gpio_chip; struct irq_domain *irq_domain; struct bcm_kona_gpio_bank *banks; struct platform_device *pdev; }; struct bcm_kona_gpio_bank { int id; int irq; /* Used in the interrupt handler */ struct bcm_kona_gpio *kona_gpio; }; static inline struct bcm_kona_gpio *to_kona_gpio(struct gpio_chip *chip) { return container_of(chip, struct bcm_kona_gpio, gpio_chip); } static void bcm_kona_gpio_set_lockcode_bank(void __iomem *reg_base, int bank_id, int lockcode) { writel(BCM_GPIO_PASSWD, reg_base + GPIO_GPPWR_OFFSET); writel(lockcode, reg_base + GPIO_PWD_STATUS(bank_id)); } static inline void bcm_kona_gpio_lock_bank(void __iomem *reg_base, int bank_id) { bcm_kona_gpio_set_lockcode_bank(reg_base, bank_id, LOCK_CODE); } static inline void bcm_kona_gpio_unlock_bank(void __iomem *reg_base, int bank_id) { bcm_kona_gpio_set_lockcode_bank(reg_base, bank_id, UNLOCK_CODE); } static void bcm_kona_gpio_set(struct gpio_chip *chip, unsigned gpio, int value) { struct bcm_kona_gpio *kona_gpio; void __iomem *reg_base; int bank_id = GPIO_BANK(gpio); int bit = GPIO_BIT(gpio); u32 val, reg_offset; unsigned long flags; kona_gpio = to_kona_gpio(chip); reg_base = kona_gpio->reg_base; spin_lock_irqsave(&kona_gpio->lock, flags); bcm_kona_gpio_unlock_bank(reg_base, bank_id); /* determine the GPIO pin direction */ val = readl(reg_base + GPIO_CONTROL(gpio)); val &= GPIO_GPCTR0_IOTR_MASK; /* this function only applies to output pin */ if (GPIO_GPCTR0_IOTR_CMD_INPUT == val) goto out; reg_offset = value ? GPIO_OUT_SET(bank_id) : GPIO_OUT_CLEAR(bank_id); val = readl(reg_base + reg_offset); val |= BIT(bit); writel(val, reg_base + reg_offset); out: bcm_kona_gpio_lock_bank(reg_base, bank_id); spin_unlock_irqrestore(&kona_gpio->lock, flags); } static int bcm_kona_gpio_get(struct gpio_chip *chip, unsigned gpio) { struct bcm_kona_gpio *kona_gpio; void __iomem *reg_base; int bank_id = GPIO_BANK(gpio); int bit = GPIO_BIT(gpio); u32 val, reg_offset; unsigned long flags; kona_gpio = to_kona_gpio(chip); reg_base = kona_gpio->reg_base; spin_lock_irqsave(&kona_gpio->lock, flags); bcm_kona_gpio_unlock_bank(reg_base, bank_id); /* determine the GPIO pin direction */ val = readl(reg_base + GPIO_CONTROL(gpio)); val &= GPIO_GPCTR0_IOTR_MASK; /* read the GPIO bank status */ reg_offset = (GPIO_GPCTR0_IOTR_CMD_INPUT == val) ? GPIO_IN_STATUS(bank_id) : GPIO_OUT_STATUS(bank_id); val = readl(reg_base + reg_offset); bcm_kona_gpio_lock_bank(reg_base, bank_id); spin_unlock_irqrestore(&kona_gpio->lock, flags); /* return the specified bit status */ return !!(val & BIT(bit)); } static int bcm_kona_gpio_direction_input(struct gpio_chip *chip, unsigned gpio) { struct bcm_kona_gpio *kona_gpio; void __iomem *reg_base; u32 val; unsigned long flags; int bank_id = GPIO_BANK(gpio); kona_gpio = to_kona_gpio(chip); reg_base = kona_gpio->reg_base; spin_lock_irqsave(&kona_gpio->lock, flags); bcm_kona_gpio_unlock_bank(reg_base, bank_id); val = readl(reg_base + GPIO_CONTROL(gpio)); val &= ~GPIO_GPCTR0_IOTR_MASK; val |= GPIO_GPCTR0_IOTR_CMD_INPUT; writel(val, reg_base + GPIO_CONTROL(gpio)); bcm_kona_gpio_lock_bank(reg_base, bank_id); spin_unlock_irqrestore(&kona_gpio->lock, flags); return 0; } static int bcm_kona_gpio_direction_output(struct gpio_chip *chip, unsigned gpio, int value) { struct bcm_kona_gpio *kona_gpio; void __iomem *reg_base; int bank_id = GPIO_BANK(gpio); int bit = GPIO_BIT(gpio); u32 val, reg_offset; unsigned long flags; kona_gpio = to_kona_gpio(chip); reg_base = kona_gpio->reg_base; spin_lock_irqsave(&kona_gpio->lock, flags); bcm_kona_gpio_unlock_bank(reg_base, bank_id); val = readl(reg_base + GPIO_CONTROL(gpio)); val &= ~GPIO_GPCTR0_IOTR_MASK; val |= GPIO_GPCTR0_IOTR_CMD_0UTPUT; writel(val, reg_base + GPIO_CONTROL(gpio)); reg_offset = value ? GPIO_OUT_SET(bank_id) : GPIO_OUT_CLEAR(bank_id); val = readl(reg_base + reg_offset); val |= BIT(bit); writel(val, reg_base + reg_offset); bcm_kona_gpio_lock_bank(reg_base, bank_id); spin_unlock_irqrestore(&kona_gpio->lock, flags); return 0; } static int bcm_kona_gpio_to_irq(struct gpio_chip *chip, unsigned gpio) { struct bcm_kona_gpio *kona_gpio; kona_gpio = to_kona_gpio(chip); if (gpio >= kona_gpio->gpio_chip.ngpio) return -ENXIO; return irq_create_mapping(kona_gpio->irq_domain, gpio); } static int bcm_kona_gpio_set_debounce(struct gpio_chip *chip, unsigned gpio, unsigned debounce) { struct bcm_kona_gpio *kona_gpio; void __iomem *reg_base; u32 val, res; unsigned long flags; int bank_id = GPIO_BANK(gpio); kona_gpio = to_kona_gpio(chip); reg_base = kona_gpio->reg_base; /* debounce must be 1-128ms (or 0) */ if ((debounce > 0 && debounce < 1000) || debounce > 128000) { dev_err(chip->dev, "Debounce value %u not in range\n", debounce); return -EINVAL; } /* calculate debounce bit value */ if (debounce != 0) { /* Convert to ms */ debounce /= 1000; /* find the MSB */ res = fls(debounce) - 1; /* Check if MSB-1 is set (round up or down) */ if (res > 0 && (debounce & BIT(res - 1))) res++; } /* spin lock for read-modify-write of the GPIO register */ spin_lock_irqsave(&kona_gpio->lock, flags); bcm_kona_gpio_unlock_bank(reg_base, bank_id); val = readl(reg_base + GPIO_CONTROL(gpio)); val &= ~GPIO_GPCTR0_DBR_MASK; if (debounce == 0) { /* disable debounce */ val &= ~GPIO_GPCTR0_DB_ENABLE_MASK; } else { val |= GPIO_GPCTR0_DB_ENABLE_MASK | (res << GPIO_GPCTR0_DBR_SHIFT); } writel(val, reg_base + GPIO_CONTROL(gpio)); bcm_kona_gpio_lock_bank(reg_base, bank_id); spin_unlock_irqrestore(&kona_gpio->lock, flags); return 0; } static struct gpio_chip template_chip = { .label = "bcm-kona-gpio", .owner = THIS_MODULE, .direction_input = bcm_kona_gpio_direction_input, .get = bcm_kona_gpio_get, .direction_output = bcm_kona_gpio_direction_output, .set = bcm_kona_gpio_set, .set_debounce = bcm_kona_gpio_set_debounce, .to_irq = bcm_kona_gpio_to_irq, .base = 0, }; static void bcm_kona_gpio_irq_ack(struct irq_data *d) { struct bcm_kona_gpio *kona_gpio; void __iomem *reg_base; int gpio = d->hwirq; int bank_id = GPIO_BANK(gpio); int bit = GPIO_BIT(gpio); u32 val; unsigned long flags; kona_gpio = irq_data_get_irq_chip_data(d); reg_base = kona_gpio->reg_base; spin_lock_irqsave(&kona_gpio->lock, flags); bcm_kona_gpio_unlock_bank(reg_base, bank_id); val = readl(reg_base + GPIO_INT_STATUS(bank_id)); val |= BIT(bit); writel(val, reg_base + GPIO_INT_STATUS(bank_id)); bcm_kona_gpio_lock_bank(reg_base, bank_id); spin_unlock_irqrestore(&kona_gpio->lock, flags); } static void bcm_kona_gpio_irq_mask(struct irq_data *d) { struct bcm_kona_gpio *kona_gpio; void __iomem *reg_base; int gpio = d->hwirq; int bank_id = GPIO_BANK(gpio); int bit = GPIO_BIT(gpio); u32 val; unsigned long flags; kona_gpio = irq_data_get_irq_chip_data(d); reg_base = kona_gpio->reg_base; spin_lock_irqsave(&kona_gpio->lock, flags); bcm_kona_gpio_unlock_bank(reg_base, bank_id); val = readl(reg_base + GPIO_INT_MASK(bank_id)); val |= BIT(bit); writel(val, reg_base + GPIO_INT_MASK(bank_id)); bcm_kona_gpio_lock_bank(reg_base, bank_id); spin_unlock_irqrestore(&kona_gpio->lock, flags); } static void bcm_kona_gpio_irq_unmask(struct irq_data *d) { struct bcm_kona_gpio *kona_gpio; void __iomem *reg_base; int gpio = d->hwirq; int bank_id = GPIO_BANK(gpio); int bit = GPIO_BIT(gpio); u32 val; unsigned long flags; kona_gpio = irq_data_get_irq_chip_data(d); reg_base = kona_gpio->reg_base; spin_lock_irqsave(&kona_gpio->lock, flags); bcm_kona_gpio_unlock_bank(reg_base, bank_id); val = readl(reg_base + GPIO_INT_MSKCLR(bank_id)); val |= BIT(bit); writel(val, reg_base + GPIO_INT_MSKCLR(bank_id)); bcm_kona_gpio_lock_bank(reg_base, bank_id); spin_unlock_irqrestore(&kona_gpio->lock, flags); } static int bcm_kona_gpio_irq_set_type(struct irq_data *d, unsigned int type) { struct bcm_kona_gpio *kona_gpio; void __iomem *reg_base; int gpio = d->hwirq; u32 lvl_type; u32 val; unsigned long flags; int bank_id = GPIO_BANK(gpio); kona_gpio = irq_data_get_irq_chip_data(d); reg_base = kona_gpio->reg_base; switch (type & IRQ_TYPE_SENSE_MASK) { case IRQ_TYPE_EDGE_RISING: lvl_type = GPIO_GPCTR0_ITR_CMD_RISING_EDGE; break; case IRQ_TYPE_EDGE_FALLING: lvl_type = GPIO_GPCTR0_ITR_CMD_FALLING_EDGE; break; case IRQ_TYPE_EDGE_BOTH: lvl_type = GPIO_GPCTR0_ITR_CMD_BOTH_EDGE; break; case IRQ_TYPE_LEVEL_HIGH: case IRQ_TYPE_LEVEL_LOW: /* BCM GPIO doesn't support level triggering */ default: dev_err(kona_gpio->gpio_chip.dev, "Invalid BCM GPIO irq type 0x%x\n", type); return -EINVAL; } spin_lock_irqsave(&kona_gpio->lock, flags); bcm_kona_gpio_unlock_bank(reg_base, bank_id); val = readl(reg_base + GPIO_CONTROL(gpio)); val &= ~GPIO_GPCTR0_ITR_MASK; val |= lvl_type << GPIO_GPCTR0_ITR_SHIFT; writel(val, reg_base + GPIO_CONTROL(gpio)); bcm_kona_gpio_lock_bank(reg_base, bank_id); spin_unlock_irqrestore(&kona_gpio->lock, flags); return 0; } static void bcm_kona_gpio_irq_handler(unsigned int irq, struct irq_desc *desc) { void __iomem *reg_base; int bit, bank_id; unsigned long sta; struct bcm_kona_gpio_bank *bank = irq_get_handler_data(irq); struct irq_chip *chip = irq_desc_get_chip(desc); chained_irq_enter(chip, desc); /* * For bank interrupts, we can't use chip_data to store the kona_gpio * pointer, since GIC needs it for its own purposes. Therefore, we get * our pointer from the bank structure. */ reg_base = bank->kona_gpio->reg_base; bank_id = bank->id; bcm_kona_gpio_unlock_bank(reg_base, bank_id); while ((sta = readl(reg_base + GPIO_INT_STATUS(bank_id)) & (~(readl(reg_base + GPIO_INT_MASK(bank_id)))))) { for_each_set_bit(bit, &sta, 32) { int hwirq = GPIO_PER_BANK * bank_id + bit; int child_irq = irq_find_mapping(bank->kona_gpio->irq_domain, hwirq); /* * Clear interrupt before handler is called so we don't * miss any interrupt occurred during executing them. */ writel(readl(reg_base + GPIO_INT_STATUS(bank_id)) | BIT(bit), reg_base + GPIO_INT_STATUS(bank_id)); /* Invoke interrupt handler */ generic_handle_irq(child_irq); } } bcm_kona_gpio_lock_bank(reg_base, bank_id); chained_irq_exit(chip, desc); } static unsigned int bcm_kona_gpio_irq_startup(struct irq_data *d) { struct bcm_kona_gpio *kona_gpio = irq_data_get_irq_chip_data(d); if (gpio_lock_as_irq(&kona_gpio->gpio_chip, d->hwirq)) dev_err(kona_gpio->gpio_chip.dev, "unable to lock HW IRQ %lu for IRQ\n", d->hwirq); bcm_kona_gpio_irq_unmask(d); return 0; } static void bcm_kona_gpio_irq_shutdown(struct irq_data *d) { struct bcm_kona_gpio *kona_gpio = irq_data_get_irq_chip_data(d); bcm_kona_gpio_irq_mask(d); gpio_unlock_as_irq(&kona_gpio->gpio_chip, d->hwirq); } static struct irq_chip bcm_gpio_irq_chip = { .name = "bcm-kona-gpio", .irq_ack = bcm_kona_gpio_irq_ack, .irq_mask = bcm_kona_gpio_irq_mask, .irq_unmask = bcm_kona_gpio_irq_unmask, .irq_set_type = bcm_kona_gpio_irq_set_type, .irq_startup = bcm_kona_gpio_irq_startup, .irq_shutdown = bcm_kona_gpio_irq_shutdown, }; static struct __initconst of_device_id bcm_kona_gpio_of_match[] = { { .compatible = "brcm,kona-gpio" }, {} }; MODULE_DEVICE_TABLE(of, bcm_kona_gpio_of_match); /* * This lock class tells lockdep that GPIO irqs are in a different * category than their parents, so it won't report false recursion. */ static struct lock_class_key gpio_lock_class; static int bcm_kona_gpio_irq_map(struct irq_domain *d, unsigned int irq, irq_hw_number_t hwirq) { int ret; ret = irq_set_chip_data(irq, d->host_data); if (ret < 0) return ret; irq_set_lockdep_class(irq, &gpio_lock_class); irq_set_chip_and_handler(irq, &bcm_gpio_irq_chip, handle_simple_irq); #ifdef CONFIG_ARM set_irq_flags(irq, IRQF_VALID); #else irq_set_noprobe(irq); #endif return 0; } static void bcm_kona_gpio_irq_unmap(struct irq_domain *d, unsigned int irq) { irq_set_chip_and_handler(irq, NULL, NULL); irq_set_chip_data(irq, NULL); } static struct irq_domain_ops bcm_kona_irq_ops = { .map = bcm_kona_gpio_irq_map, .unmap = bcm_kona_gpio_irq_unmap, .xlate = irq_domain_xlate_twocell, }; static void bcm_kona_gpio_reset(struct bcm_kona_gpio *kona_gpio) { void __iomem *reg_base; int i; reg_base = kona_gpio->reg_base; /* disable interrupts and clear status */ for (i = 0; i < kona_gpio->num_bank; i++) { bcm_kona_gpio_unlock_bank(reg_base, i); writel(0xffffffff, reg_base + GPIO_INT_MASK(i)); writel(0xffffffff, reg_base + GPIO_INT_STATUS(i)); bcm_kona_gpio_lock_bank(reg_base, i); } } static int bcm_kona_gpio_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; const struct of_device_id *match; struct resource *res; struct bcm_kona_gpio_bank *bank; struct bcm_kona_gpio *kona_gpio; struct gpio_chip *chip; int ret; int i; match = of_match_device(bcm_kona_gpio_of_match, dev); if (!match) { dev_err(dev, "Failed to find gpio controller\n"); return -ENODEV; } kona_gpio = devm_kzalloc(dev, sizeof(*kona_gpio), GFP_KERNEL); if (!kona_gpio) return -ENOMEM; kona_gpio->gpio_chip = template_chip; chip = &kona_gpio->gpio_chip; kona_gpio->num_bank = of_irq_count(dev->of_node); if (kona_gpio->num_bank == 0) { dev_err(dev, "Couldn't determine # GPIO banks\n"); return -ENOENT; } if (kona_gpio->num_bank > GPIO_MAX_BANK_NUM) { dev_err(dev, "Too many GPIO banks configured (max=%d)\n", GPIO_MAX_BANK_NUM); return -ENXIO; } kona_gpio->banks = devm_kzalloc(dev, kona_gpio->num_bank * sizeof(*kona_gpio->banks), GFP_KERNEL); if (!kona_gpio->banks) return -ENOMEM; kona_gpio->pdev = pdev; platform_set_drvdata(pdev, kona_gpio); chip->of_node = dev->of_node; chip->ngpio = kona_gpio->num_bank * GPIO_PER_BANK; kona_gpio->irq_domain = irq_domain_add_linear(dev->of_node, chip->ngpio, &bcm_kona_irq_ops, kona_gpio); if (!kona_gpio->irq_domain) { dev_err(dev, "Couldn't allocate IRQ domain\n"); return -ENXIO; } res = platform_get_resource(pdev, IORESOURCE_MEM, 0); kona_gpio->reg_base = devm_ioremap_resource(dev, res); if (IS_ERR(kona_gpio->reg_base)) { ret = -ENXIO; goto err_irq_domain; } for (i = 0; i < kona_gpio->num_bank; i++) { bank = &kona_gpio->banks[i]; bank->id = i; bank->irq = platform_get_irq(pdev, i); bank->kona_gpio = kona_gpio; if (bank->irq < 0) { dev_err(dev, "Couldn't get IRQ for bank %d", i); ret = -ENOENT; goto err_irq_domain; } } dev_info(&pdev->dev, "Setting up Kona GPIO\n"); bcm_kona_gpio_reset(kona_gpio); ret = gpiochip_add(chip); if (ret < 0) { dev_err(dev, "Couldn't add GPIO chip -- %d\n", ret); goto err_irq_domain; } for (i = 0; i < chip->ngpio; i++) { int irq = bcm_kona_gpio_to_irq(chip, i); irq_set_lockdep_class(irq, &gpio_lock_class); irq_set_chip_and_handler(irq, &bcm_gpio_irq_chip, handle_simple_irq); #ifdef CONFIG_ARM set_irq_flags(irq, IRQF_VALID); #else irq_set_noprobe(irq); #endif } for (i = 0; i < kona_gpio->num_bank; i++) { bank = &kona_gpio->banks[i]; irq_set_chained_handler(bank->irq, bcm_kona_gpio_irq_handler); irq_set_handler_data(bank->irq, bank); } spin_lock_init(&kona_gpio->lock); return 0; err_irq_domain: irq_domain_remove(kona_gpio->irq_domain); return ret; } static struct platform_driver bcm_kona_gpio_driver = { .driver = { .name = "bcm-kona-gpio", .owner = THIS_MODULE, .of_match_table = bcm_kona_gpio_of_match, }, .probe = bcm_kona_gpio_probe, }; module_platform_driver(bcm_kona_gpio_driver); MODULE_AUTHOR("Broadcom Corporation <bcm-kernel-feedback-list@broadcom.com>"); MODULE_DESCRIPTION("Broadcom Kona GPIO Driver"); MODULE_LICENSE("GPL v2");