diff options
Diffstat (limited to 'drivers/gpio/gpio-brcmstb.c')
-rw-r--r-- | drivers/gpio/gpio-brcmstb.c | 306 |
1 files changed, 300 insertions, 6 deletions
diff --git a/drivers/gpio/gpio-brcmstb.c b/drivers/gpio/gpio-brcmstb.c index 4630a8133..4c64627c6 100644 --- a/drivers/gpio/gpio-brcmstb.c +++ b/drivers/gpio/gpio-brcmstb.c @@ -17,6 +17,10 @@ #include <linux/of_irq.h> #include <linux/module.h> #include <linux/basic_mmio_gpio.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) @@ -34,14 +38,18 @@ struct brcmstb_gpio_bank { struct bgpio_chip bgc; 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; - int num_banks; 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 @@ -63,6 +71,203 @@ brcmstb_gpio_gc_to_priv(struct gpio_chip *gc) return bank->parent_priv; } +static void brcmstb_gpio_set_imask(struct brcmstb_gpio_bank *bank, + unsigned int offset, bool enable) +{ + struct bgpio_chip *bgc = &bank->bgc; + struct brcmstb_gpio_priv *priv = bank->parent_priv; + u32 mask = bgc->pin2mask(bgc, offset); + u32 imask; + unsigned long flags; + + spin_lock_irqsave(&bgc->lock, flags); + imask = bgc->read_reg(priv->reg_base + GIO_MASK(bank->id)); + if (enable) + imask |= mask; + else + imask &= ~mask; + bgc->write_reg(priv->reg_base + GIO_MASK(bank->id), imask); + spin_unlock_irqrestore(&bgc->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 = brcmstb_gpio_gc_to_bank(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 = brcmstb_gpio_gc_to_bank(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 = brcmstb_gpio_gc_to_bank(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->bgc.lock, flags); + + iedge_config = bank->bgc.read_reg(priv->reg_base + + GIO_EC(bank->id)) & ~mask; + iedge_insensitive = bank->bgc.read_reg(priv->reg_base + + GIO_EI(bank->id)) & ~mask; + ilevel = bank->bgc.read_reg(priv->reg_base + + GIO_LEVEL(bank->id)) & ~mask; + + bank->bgc.write_reg(priv->reg_base + GIO_EC(bank->id), + iedge_config | edge_config); + bank->bgc.write_reg(priv->reg_base + GIO_EI(bank->id), + iedge_insensitive | edge_insensitive); + bank->bgc.write_reg(priv->reg_base + GIO_LEVEL(bank->id), + ilevel | level); + + spin_unlock_irqrestore(&bank->bgc.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->bgc.gc.irqdomain; + void __iomem *reg_base = priv->reg_base; + unsigned long status; + unsigned long flags; + + spin_lock_irqsave(&bank->bgc.lock, flags); + while ((status = bank->bgc.read_reg(reg_base + GIO_STAT(bank->id)) & + bank->bgc.read_reg(reg_base + GIO_MASK(bank->id)))) { + int bit; + + for_each_set_bit(bit, &status, 32) { + u32 stat = bank->bgc.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->bgc.write_reg(reg_base + GIO_STAT(bank->id), + stat | BIT(bit)); + generic_handle_irq(irq_find_mapping(irq_domain, bit)); + } + } + spin_unlock_irqrestore(&bank->bgc.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 list_head *pos; + + /* Interrupts weren't properly cleared during probe */ + BUG_ON(!priv || !chip); + + chained_irq_enter(chip, desc); + list_for_each(pos, &priv->bank_list) { + struct brcmstb_gpio_bank *bank = + list_entry(pos, struct brcmstb_gpio_bank, 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) @@ -100,7 +305,13 @@ static int brcmstb_gpio_remove(struct platform_device *pdev) bank = list_entry(pos, struct brcmstb_gpio_bank, node); ret = bgpio_remove(&bank->bgc); if (ret) - dev_err(&pdev->dev, "gpiochip_remove fail in cleanup"); + dev_err(&pdev->dev, "gpiochip_remove fail in cleanup\n"); + } + 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; } @@ -121,7 +332,7 @@ static int brcmstb_gpio_of_xlate(struct gpio_chip *gc, return -EINVAL; offset = gpiospec->args[0] - (gc->base - priv->gpio_base); - if (offset >= gc->ngpio) + if (offset >= gc->ngpio || offset < 0) return -EINVAL; if (unlikely(offset >= bank->width)) { @@ -136,6 +347,65 @@ static int brcmstb_gpio_of_xlate(struct gpio_chip *gc, 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->bgc.gc, &bank->irq_chip, 0, + handle_simple_irq, IRQ_TYPE_NONE); + gpiochip_set_chained_irqchip(&bank->bgc.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; @@ -146,6 +416,7 @@ static int brcmstb_gpio_probe(struct platform_device *pdev) struct property *prop; const __be32 *p; u32 bank_width; + int num_banks = 0; int err; static int gpio_base; @@ -164,6 +435,16 @@ static int brcmstb_gpio_probe(struct platform_device *pdev) 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; @@ -180,7 +461,7 @@ static int brcmstb_gpio_probe(struct platform_device *pdev) } bank->parent_priv = priv; - bank->id = priv->num_banks; + bank->id = num_banks; if (bank_width <= 0 || bank_width > MAX_GPIO_PER_BANK) { dev_err(dev, "Invalid bank width %d\n", bank_width); goto fail; @@ -212,6 +493,12 @@ static int brcmstb_gpio_probe(struct platform_device *pdev) /* 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 + */ + bank->bgc.write_reg(reg_base + GIO_MASK(bank->id), 0); + err = gpiochip_add(gc); if (err) { dev_err(dev, "Could not add gpiochip for bank %d\n", @@ -219,17 +506,24 @@ static int brcmstb_gpio_probe(struct platform_device *pdev) 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); - priv->num_banks++; + num_banks++; } dev_info(dev, "Registered %d banks (GPIO(s): %d-%d)\n", - priv->num_banks, priv->gpio_base, gpio_base - 1); + num_banks, priv->gpio_base, gpio_base - 1); return 0; |