| /* |
| * Copyright (C) 2015 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/gpio/driver.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> |
| #include <linux/interrupt.h> |
| #include <linux/reboot.h> |
| |
| #define GIO_BANK_SIZE 0x20 |
| #define GIO_ODEN(bank) (((bank) * GIO_BANK_SIZE) + 0x00) |
| #define GIO_DATA(bank) (((bank) * GIO_BANK_SIZE) + 0x04) |
| #define GIO_IODIR(bank) (((bank) * GIO_BANK_SIZE) + 0x08) |
| #define GIO_EC(bank) (((bank) * GIO_BANK_SIZE) + 0x0c) |
| #define GIO_EI(bank) (((bank) * GIO_BANK_SIZE) + 0x10) |
| #define GIO_MASK(bank) (((bank) * GIO_BANK_SIZE) + 0x14) |
| #define GIO_LEVEL(bank) (((bank) * GIO_BANK_SIZE) + 0x18) |
| #define GIO_STAT(bank) (((bank) * GIO_BANK_SIZE) + 0x1c) |
| |
| struct brcmstb_gpio_bank { |
| struct list_head node; |
| int id; |
| struct gpio_chip gc; |
| struct brcmstb_gpio_priv *parent_priv; |
| u32 width; |
| struct irq_chip irq_chip; |
| }; |
| |
| struct brcmstb_gpio_priv { |
| struct list_head bank_list; |
| void __iomem *reg_base; |
| struct platform_device *pdev; |
| int parent_irq; |
| int gpio_base; |
| bool can_wake; |
| int parent_wake_irq; |
| struct notifier_block reboot_notifier; |
| }; |
| |
| #define MAX_GPIO_PER_BANK 32 |
| #define GPIO_BANK(gpio) ((gpio) >> 5) |
| /* assumes MAX_GPIO_PER_BANK is a multiple of 2 */ |
| #define GPIO_BIT(gpio) ((gpio) & (MAX_GPIO_PER_BANK - 1)) |
| |
| static inline struct brcmstb_gpio_priv * |
| brcmstb_gpio_gc_to_priv(struct gpio_chip *gc) |
| { |
| struct brcmstb_gpio_bank *bank = gpiochip_get_data(gc); |
| return bank->parent_priv; |
| } |
| |
| static void brcmstb_gpio_set_imask(struct brcmstb_gpio_bank *bank, |
| unsigned int offset, bool enable) |
| { |
| struct gpio_chip *gc = &bank->gc; |
| struct brcmstb_gpio_priv *priv = bank->parent_priv; |
| u32 mask = gc->pin2mask(gc, offset); |
| u32 imask; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&gc->bgpio_lock, flags); |
| imask = gc->read_reg(priv->reg_base + GIO_MASK(bank->id)); |
| if (enable) |
| imask |= mask; |
| else |
| imask &= ~mask; |
| gc->write_reg(priv->reg_base + GIO_MASK(bank->id), imask); |
| spin_unlock_irqrestore(&gc->bgpio_lock, flags); |
| } |
| |
| /* -------------------- IRQ chip functions -------------------- */ |
| |
| static void brcmstb_gpio_irq_mask(struct irq_data *d) |
| { |
| struct gpio_chip *gc = irq_data_get_irq_chip_data(d); |
| struct brcmstb_gpio_bank *bank = gpiochip_get_data(gc); |
| |
| brcmstb_gpio_set_imask(bank, d->hwirq, false); |
| } |
| |
| static void brcmstb_gpio_irq_unmask(struct irq_data *d) |
| { |
| struct gpio_chip *gc = irq_data_get_irq_chip_data(d); |
| struct brcmstb_gpio_bank *bank = gpiochip_get_data(gc); |
| |
| brcmstb_gpio_set_imask(bank, d->hwirq, true); |
| } |
| |
| static int brcmstb_gpio_irq_set_type(struct irq_data *d, unsigned int type) |
| { |
| struct gpio_chip *gc = irq_data_get_irq_chip_data(d); |
| struct brcmstb_gpio_bank *bank = gpiochip_get_data(gc); |
| struct brcmstb_gpio_priv *priv = bank->parent_priv; |
| u32 mask = BIT(d->hwirq); |
| u32 edge_insensitive, iedge_insensitive; |
| u32 edge_config, iedge_config; |
| u32 level, ilevel; |
| unsigned long flags; |
| |
| switch (type) { |
| case IRQ_TYPE_LEVEL_LOW: |
| level = 0; |
| edge_config = 0; |
| edge_insensitive = 0; |
| break; |
| case IRQ_TYPE_LEVEL_HIGH: |
| level = mask; |
| edge_config = 0; |
| edge_insensitive = 0; |
| break; |
| case IRQ_TYPE_EDGE_FALLING: |
| level = 0; |
| edge_config = 0; |
| edge_insensitive = 0; |
| break; |
| case IRQ_TYPE_EDGE_RISING: |
| level = 0; |
| edge_config = mask; |
| edge_insensitive = 0; |
| break; |
| case IRQ_TYPE_EDGE_BOTH: |
| level = 0; |
| edge_config = 0; /* don't care, but want known value */ |
| edge_insensitive = mask; |
| break; |
| default: |
| return -EINVAL; |
| } |
| |
| spin_lock_irqsave(&bank->gc.bgpio_lock, flags); |
| |
| iedge_config = bank->gc.read_reg(priv->reg_base + |
| GIO_EC(bank->id)) & ~mask; |
| iedge_insensitive = bank->gc.read_reg(priv->reg_base + |
| GIO_EI(bank->id)) & ~mask; |
| ilevel = bank->gc.read_reg(priv->reg_base + |
| GIO_LEVEL(bank->id)) & ~mask; |
| |
| bank->gc.write_reg(priv->reg_base + GIO_EC(bank->id), |
| iedge_config | edge_config); |
| bank->gc.write_reg(priv->reg_base + GIO_EI(bank->id), |
| iedge_insensitive | edge_insensitive); |
| bank->gc.write_reg(priv->reg_base + GIO_LEVEL(bank->id), |
| ilevel | level); |
| |
| spin_unlock_irqrestore(&bank->gc.bgpio_lock, flags); |
| return 0; |
| } |
| |
| static int brcmstb_gpio_priv_set_wake(struct brcmstb_gpio_priv *priv, |
| unsigned int enable) |
| { |
| int ret = 0; |
| |
| /* |
| * Only enable wake IRQ once for however many hwirqs can wake |
| * since they all use the same wake IRQ. Mask will be set |
| * up appropriately thanks to IRQCHIP_MASK_ON_SUSPEND flag. |
| */ |
| if (enable) |
| ret = enable_irq_wake(priv->parent_wake_irq); |
| else |
| ret = disable_irq_wake(priv->parent_wake_irq); |
| if (ret) |
| dev_err(&priv->pdev->dev, "failed to %s wake-up interrupt\n", |
| enable ? "enable" : "disable"); |
| return ret; |
| } |
| |
| static int brcmstb_gpio_irq_set_wake(struct irq_data *d, unsigned int enable) |
| { |
| struct gpio_chip *gc = irq_data_get_irq_chip_data(d); |
| struct brcmstb_gpio_priv *priv = brcmstb_gpio_gc_to_priv(gc); |
| |
| return brcmstb_gpio_priv_set_wake(priv, enable); |
| } |
| |
| static irqreturn_t brcmstb_gpio_wake_irq_handler(int irq, void *data) |
| { |
| struct brcmstb_gpio_priv *priv = data; |
| |
| if (!priv || irq != priv->parent_wake_irq) |
| return IRQ_NONE; |
| pm_wakeup_event(&priv->pdev->dev, 0); |
| return IRQ_HANDLED; |
| } |
| |
| static void brcmstb_gpio_irq_bank_handler(struct brcmstb_gpio_bank *bank) |
| { |
| struct brcmstb_gpio_priv *priv = bank->parent_priv; |
| struct irq_domain *irq_domain = bank->gc.irqdomain; |
| void __iomem *reg_base = priv->reg_base; |
| unsigned long status; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&bank->gc.bgpio_lock, flags); |
| while ((status = bank->gc.read_reg(reg_base + GIO_STAT(bank->id)) & |
| bank->gc.read_reg(reg_base + GIO_MASK(bank->id)))) { |
| int bit; |
| |
| for_each_set_bit(bit, &status, 32) { |
| u32 stat = bank->gc.read_reg(reg_base + |
| GIO_STAT(bank->id)); |
| if (bit >= bank->width) |
| dev_warn(&priv->pdev->dev, |
| "IRQ for invalid GPIO (bank=%d, offset=%d)\n", |
| bank->id, bit); |
| bank->gc.write_reg(reg_base + GIO_STAT(bank->id), |
| stat | BIT(bit)); |
| generic_handle_irq(irq_find_mapping(irq_domain, bit)); |
| } |
| } |
| spin_unlock_irqrestore(&bank->gc.bgpio_lock, flags); |
| } |
| |
| /* Each UPG GIO block has one IRQ for all banks */ |
| static void brcmstb_gpio_irq_handler(struct irq_desc *desc) |
| { |
| struct gpio_chip *gc = irq_desc_get_handler_data(desc); |
| struct brcmstb_gpio_priv *priv = brcmstb_gpio_gc_to_priv(gc); |
| struct irq_chip *chip = irq_desc_get_chip(desc); |
| struct brcmstb_gpio_bank *bank; |
| |
| /* Interrupts weren't properly cleared during probe */ |
| BUG_ON(!priv || !chip); |
| |
| chained_irq_enter(chip, desc); |
| list_for_each_entry(bank, &priv->bank_list, node) |
| brcmstb_gpio_irq_bank_handler(bank); |
| chained_irq_exit(chip, desc); |
| } |
| |
| static int brcmstb_gpio_reboot(struct notifier_block *nb, |
| unsigned long action, void *data) |
| { |
| struct brcmstb_gpio_priv *priv = |
| container_of(nb, struct brcmstb_gpio_priv, reboot_notifier); |
| |
| /* Enable GPIO for S5 cold boot */ |
| if (action == SYS_POWER_OFF) |
| brcmstb_gpio_priv_set_wake(priv, 1); |
| |
| return NOTIFY_DONE; |
| } |
| |
| /* Make sure that the number of banks matches up between properties */ |
| static int brcmstb_gpio_sanity_check_banks(struct device *dev, |
| struct device_node *np, struct resource *res) |
| { |
| int res_num_banks = resource_size(res) / GIO_BANK_SIZE; |
| int num_banks = |
| of_property_count_u32_elems(np, "brcm,gpio-bank-widths"); |
| |
| if (res_num_banks != num_banks) { |
| dev_err(dev, "Mismatch in banks: res had %d, bank-widths had %d\n", |
| res_num_banks, num_banks); |
| return -EINVAL; |
| } else { |
| return 0; |
| } |
| } |
| |
| static int brcmstb_gpio_remove(struct platform_device *pdev) |
| { |
| struct brcmstb_gpio_priv *priv = platform_get_drvdata(pdev); |
| struct brcmstb_gpio_bank *bank; |
| int ret = 0; |
| |
| if (!priv) { |
| dev_err(&pdev->dev, "called %s without drvdata!\n", __func__); |
| return -EFAULT; |
| } |
| |
| /* |
| * You can lose return values below, but we report all errors, and it's |
| * more important to actually perform all of the steps. |
| */ |
| list_for_each_entry(bank, &priv->bank_list, node) |
| gpiochip_remove(&bank->gc); |
| |
| if (priv->reboot_notifier.notifier_call) { |
| ret = unregister_reboot_notifier(&priv->reboot_notifier); |
| if (ret) |
| dev_err(&pdev->dev, |
| "failed to unregister reboot notifier\n"); |
| } |
| return ret; |
| } |
| |
| static int brcmstb_gpio_of_xlate(struct gpio_chip *gc, |
| const struct of_phandle_args *gpiospec, u32 *flags) |
| { |
| struct brcmstb_gpio_priv *priv = brcmstb_gpio_gc_to_priv(gc); |
| struct brcmstb_gpio_bank *bank = gpiochip_get_data(gc); |
| int offset; |
| |
| if (gc->of_gpio_n_cells != 2) { |
| WARN_ON(1); |
| return -EINVAL; |
| } |
| |
| if (WARN_ON(gpiospec->args_count < gc->of_gpio_n_cells)) |
| return -EINVAL; |
| |
| offset = gpiospec->args[0] - (gc->base - priv->gpio_base); |
| if (offset >= gc->ngpio || offset < 0) |
| return -EINVAL; |
| |
| if (unlikely(offset >= bank->width)) { |
| dev_warn_ratelimited(&priv->pdev->dev, |
| "Received request for invalid GPIO offset %d\n", |
| gpiospec->args[0]); |
| } |
| |
| if (flags) |
| *flags = gpiospec->args[1]; |
| |
| return offset; |
| } |
| |
| /* Before calling, must have bank->parent_irq set and gpiochip registered */ |
| static int brcmstb_gpio_irq_setup(struct platform_device *pdev, |
| struct brcmstb_gpio_bank *bank) |
| { |
| struct brcmstb_gpio_priv *priv = bank->parent_priv; |
| struct device *dev = &pdev->dev; |
| struct device_node *np = dev->of_node; |
| |
| bank->irq_chip.name = dev_name(dev); |
| bank->irq_chip.irq_mask = brcmstb_gpio_irq_mask; |
| bank->irq_chip.irq_unmask = brcmstb_gpio_irq_unmask; |
| bank->irq_chip.irq_set_type = brcmstb_gpio_irq_set_type; |
| |
| /* Ensures that all non-wakeup IRQs are disabled at suspend */ |
| bank->irq_chip.flags = IRQCHIP_MASK_ON_SUSPEND; |
| |
| if (IS_ENABLED(CONFIG_PM_SLEEP) && !priv->can_wake && |
| of_property_read_bool(np, "wakeup-source")) { |
| priv->parent_wake_irq = platform_get_irq(pdev, 1); |
| if (priv->parent_wake_irq < 0) { |
| dev_warn(dev, |
| "Couldn't get wake IRQ - GPIOs will not be able to wake from sleep"); |
| } else { |
| int err; |
| |
| /* |
| * Set wakeup capability before requesting wakeup |
| * interrupt, so we can process boot-time "wakeups" |
| * (e.g., from S5 cold boot) |
| */ |
| device_set_wakeup_capable(dev, true); |
| device_wakeup_enable(dev); |
| err = devm_request_irq(dev, priv->parent_wake_irq, |
| brcmstb_gpio_wake_irq_handler, 0, |
| "brcmstb-gpio-wake", priv); |
| |
| if (err < 0) { |
| dev_err(dev, "Couldn't request wake IRQ"); |
| return err; |
| } |
| |
| priv->reboot_notifier.notifier_call = |
| brcmstb_gpio_reboot; |
| register_reboot_notifier(&priv->reboot_notifier); |
| priv->can_wake = true; |
| } |
| } |
| |
| if (priv->can_wake) |
| bank->irq_chip.irq_set_wake = brcmstb_gpio_irq_set_wake; |
| |
| gpiochip_irqchip_add(&bank->gc, &bank->irq_chip, 0, |
| handle_simple_irq, IRQ_TYPE_NONE); |
| gpiochip_set_chained_irqchip(&bank->gc, &bank->irq_chip, |
| priv->parent_irq, brcmstb_gpio_irq_handler); |
| |
| return 0; |
| } |
| |
| static int brcmstb_gpio_probe(struct platform_device *pdev) |
| { |
| struct device *dev = &pdev->dev; |
| struct device_node *np = dev->of_node; |
| void __iomem *reg_base; |
| struct brcmstb_gpio_priv *priv; |
| struct resource *res; |
| struct property *prop; |
| const __be32 *p; |
| u32 bank_width; |
| int num_banks = 0; |
| int err; |
| static int gpio_base; |
| unsigned long flags = 0; |
| |
| priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); |
| if (!priv) |
| return -ENOMEM; |
| platform_set_drvdata(pdev, priv); |
| INIT_LIST_HEAD(&priv->bank_list); |
| |
| res = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| reg_base = devm_ioremap_resource(dev, res); |
| if (IS_ERR(reg_base)) |
| return PTR_ERR(reg_base); |
| |
| priv->gpio_base = gpio_base; |
| priv->reg_base = reg_base; |
| priv->pdev = pdev; |
| |
| if (of_property_read_bool(np, "interrupt-controller")) { |
| priv->parent_irq = platform_get_irq(pdev, 0); |
| if (priv->parent_irq <= 0) { |
| dev_err(dev, "Couldn't get IRQ"); |
| return -ENOENT; |
| } |
| } else { |
| priv->parent_irq = -ENOENT; |
| } |
| |
| if (brcmstb_gpio_sanity_check_banks(dev, np, res)) |
| return -EINVAL; |
| |
| /* |
| * MIPS endianness is configured by boot strap, which also reverses all |
| * bus endianness (i.e., big-endian CPU + big endian bus ==> native |
| * endian I/O). |
| * |
| * Other architectures (e.g., ARM) either do not support big endian, or |
| * else leave I/O in little endian mode. |
| */ |
| #if defined(CONFIG_MIPS) && defined(__BIG_ENDIAN) |
| flags = BGPIOF_BIG_ENDIAN_BYTE_ORDER; |
| #endif |
| |
| of_property_for_each_u32(np, "brcm,gpio-bank-widths", prop, p, |
| bank_width) { |
| struct brcmstb_gpio_bank *bank; |
| struct gpio_chip *gc; |
| |
| bank = devm_kzalloc(dev, sizeof(*bank), GFP_KERNEL); |
| if (!bank) { |
| err = -ENOMEM; |
| goto fail; |
| } |
| |
| bank->parent_priv = priv; |
| bank->id = num_banks; |
| if (bank_width <= 0 || bank_width > MAX_GPIO_PER_BANK) { |
| dev_err(dev, "Invalid bank width %d\n", bank_width); |
| err = -EINVAL; |
| goto fail; |
| } else { |
| bank->width = bank_width; |
| } |
| |
| /* |
| * Regs are 4 bytes wide, have data reg, no set/clear regs, |
| * and direction bits have 0 = output and 1 = input |
| */ |
| gc = &bank->gc; |
| err = bgpio_init(gc, dev, 4, |
| reg_base + GIO_DATA(bank->id), |
| NULL, NULL, NULL, |
| reg_base + GIO_IODIR(bank->id), flags); |
| if (err) { |
| dev_err(dev, "bgpio_init() failed\n"); |
| goto fail; |
| } |
| |
| gc->of_node = np; |
| gc->owner = THIS_MODULE; |
| gc->label = np->full_name; |
| gc->base = gpio_base; |
| gc->of_gpio_n_cells = 2; |
| gc->of_xlate = brcmstb_gpio_of_xlate; |
| /* not all ngpio lines are valid, will use bank width later */ |
| gc->ngpio = MAX_GPIO_PER_BANK; |
| |
| /* |
| * Mask all interrupts by default, since wakeup interrupts may |
| * be retained from S5 cold boot |
| */ |
| gc->write_reg(reg_base + GIO_MASK(bank->id), 0); |
| |
| err = gpiochip_add_data(gc, bank); |
| if (err) { |
| dev_err(dev, "Could not add gpiochip for bank %d\n", |
| bank->id); |
| goto fail; |
| } |
| gpio_base += gc->ngpio; |
| |
| if (priv->parent_irq > 0) { |
| err = brcmstb_gpio_irq_setup(pdev, bank); |
| if (err) |
| goto fail; |
| } |
| |
| dev_dbg(dev, "bank=%d, base=%d, ngpio=%d, width=%d\n", bank->id, |
| gc->base, gc->ngpio, bank->width); |
| |
| /* Everything looks good, so add bank to list */ |
| list_add(&bank->node, &priv->bank_list); |
| |
| num_banks++; |
| } |
| |
| dev_info(dev, "Registered %d banks (GPIO(s): %d-%d)\n", |
| num_banks, priv->gpio_base, gpio_base - 1); |
| |
| return 0; |
| |
| fail: |
| (void) brcmstb_gpio_remove(pdev); |
| return err; |
| } |
| |
| static const struct of_device_id brcmstb_gpio_of_match[] = { |
| { .compatible = "brcm,brcmstb-gpio" }, |
| {}, |
| }; |
| |
| MODULE_DEVICE_TABLE(of, brcmstb_gpio_of_match); |
| |
| static struct platform_driver brcmstb_gpio_driver = { |
| .driver = { |
| .name = "brcmstb-gpio", |
| .of_match_table = brcmstb_gpio_of_match, |
| }, |
| .probe = brcmstb_gpio_probe, |
| .remove = brcmstb_gpio_remove, |
| }; |
| module_platform_driver(brcmstb_gpio_driver); |
| |
| MODULE_AUTHOR("Gregory Fong"); |
| MODULE_DESCRIPTION("Driver for Broadcom BRCMSTB SoC UPG GPIO"); |
| MODULE_LICENSE("GPL v2"); |