diff options
Diffstat (limited to 'drivers/gpio/gpio-tangier.c')
| -rw-r--r-- | drivers/gpio/gpio-tangier.c | 536 |
1 files changed, 536 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-tangier.c b/drivers/gpio/gpio-tangier.c new file mode 100644 index 000000000000..e990781935ba --- /dev/null +++ b/drivers/gpio/gpio-tangier.c @@ -0,0 +1,536 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Intel Tangier GPIO driver + * + * Copyright (c) 2016, 2021, 2023 Intel Corporation. + * + * Authors: Andy Shevchenko <[email protected]> + * Pandith N <[email protected]> + * Raag Jadav <[email protected]> + */ + +#include <linux/bitops.h> +#include <linux/device.h> +#include <linux/errno.h> +#include <linux/export.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/irq.h> +#include <linux/module.h> +#include <linux/pinctrl/pinconf-generic.h> +#include <linux/spinlock.h> +#include <linux/string_helpers.h> +#include <linux/types.h> + +#include <linux/gpio/driver.h> + +#include "gpio-tangier.h" + +#define GCCR 0x000 /* Controller configuration */ +#define GPLR 0x004 /* Pin level r/o */ +#define GPDR 0x01c /* Pin direction */ +#define GPSR 0x034 /* Pin set w/o */ +#define GPCR 0x04c /* Pin clear w/o */ +#define GRER 0x064 /* Rising edge detect */ +#define GFER 0x07c /* Falling edge detect */ +#define GFBR 0x094 /* Glitch filter bypass */ +#define GIMR 0x0ac /* Interrupt mask */ +#define GISR 0x0c4 /* Interrupt source */ +#define GITR 0x300 /* Input type */ +#define GLPR 0x318 /* Level input polarity */ + +/** + * struct tng_gpio_context - Context to be saved during suspend-resume + * @level: Pin level + * @gpdr: Pin direction + * @grer: Rising edge detect enable + * @gfer: Falling edge detect enable + * @gimr: Interrupt mask + * @gwmr: Wake mask + */ +struct tng_gpio_context { + u32 level; + u32 gpdr; + u32 grer; + u32 gfer; + u32 gimr; + u32 gwmr; +}; + +static void __iomem *gpio_reg(struct gpio_chip *chip, unsigned int offset, + unsigned int reg) +{ + struct tng_gpio *priv = gpiochip_get_data(chip); + u8 reg_offset = offset / 32; + + return priv->reg_base + reg + reg_offset * 4; +} + +static void __iomem *gpio_reg_and_bit(struct gpio_chip *chip, unsigned int offset, + unsigned int reg, u8 *bit) +{ + struct tng_gpio *priv = gpiochip_get_data(chip); + u8 reg_offset = offset / 32; + u8 shift = offset % 32; + + *bit = shift; + return priv->reg_base + reg + reg_offset * 4; +} + +static int tng_gpio_get(struct gpio_chip *chip, unsigned int offset) +{ + void __iomem *gplr; + u8 shift; + + gplr = gpio_reg_and_bit(chip, offset, GPLR, &shift); + + return !!(readl(gplr) & BIT(shift)); +} + +static void tng_gpio_set(struct gpio_chip *chip, unsigned int offset, int value) +{ + struct tng_gpio *priv = gpiochip_get_data(chip); + unsigned long flags; + void __iomem *reg; + u8 shift; + + reg = gpio_reg_and_bit(chip, offset, value ? GPSR : GPCR, &shift); + + raw_spin_lock_irqsave(&priv->lock, flags); + + writel(BIT(shift), reg); + + raw_spin_unlock_irqrestore(&priv->lock, flags); +} + +static int tng_gpio_direction_input(struct gpio_chip *chip, unsigned int offset) +{ + struct tng_gpio *priv = gpiochip_get_data(chip); + unsigned long flags; + void __iomem *gpdr; + u32 value; + u8 shift; + + gpdr = gpio_reg_and_bit(chip, offset, GPDR, &shift); + + raw_spin_lock_irqsave(&priv->lock, flags); + + value = readl(gpdr); + value &= ~BIT(shift); + writel(value, gpdr); + + raw_spin_unlock_irqrestore(&priv->lock, flags); + + return 0; +} + +static int tng_gpio_direction_output(struct gpio_chip *chip, unsigned int offset, + int value) +{ + struct tng_gpio *priv = gpiochip_get_data(chip); + unsigned long flags; + void __iomem *gpdr; + u8 shift; + + gpdr = gpio_reg_and_bit(chip, offset, GPDR, &shift); + tng_gpio_set(chip, offset, value); + + raw_spin_lock_irqsave(&priv->lock, flags); + + value = readl(gpdr); + value |= BIT(shift); + writel(value, gpdr); + + raw_spin_unlock_irqrestore(&priv->lock, flags); + + return 0; +} + +static int tng_gpio_get_direction(struct gpio_chip *chip, unsigned int offset) +{ + void __iomem *gpdr; + u8 shift; + + gpdr = gpio_reg_and_bit(chip, offset, GPDR, &shift); + + if (readl(gpdr) & BIT(shift)) + return GPIO_LINE_DIRECTION_OUT; + + return GPIO_LINE_DIRECTION_IN; +} + +static int tng_gpio_set_debounce(struct gpio_chip *chip, unsigned int offset, + unsigned int debounce) +{ + struct tng_gpio *priv = gpiochip_get_data(chip); + unsigned long flags; + void __iomem *gfbr; + u32 value; + u8 shift; + + gfbr = gpio_reg_and_bit(chip, offset, GFBR, &shift); + + raw_spin_lock_irqsave(&priv->lock, flags); + + value = readl(gfbr); + if (debounce) + value &= ~BIT(shift); + else + value |= BIT(shift); + writel(value, gfbr); + + raw_spin_unlock_irqrestore(&priv->lock, flags); + + return 0; +} + +static int tng_gpio_set_config(struct gpio_chip *chip, unsigned int offset, + unsigned long config) +{ + u32 debounce; + + switch (pinconf_to_config_param(config)) { + case PIN_CONFIG_BIAS_DISABLE: + case PIN_CONFIG_BIAS_PULL_UP: + case PIN_CONFIG_BIAS_PULL_DOWN: + return gpiochip_generic_config(chip, offset, config); + case PIN_CONFIG_INPUT_DEBOUNCE: + debounce = pinconf_to_config_argument(config); + return tng_gpio_set_debounce(chip, offset, debounce); + default: + return -ENOTSUPP; + } +} + +static void tng_irq_ack(struct irq_data *d) +{ + struct tng_gpio *priv = irq_data_get_irq_chip_data(d); + irq_hw_number_t gpio = irqd_to_hwirq(d); + unsigned long flags; + void __iomem *gisr; + u8 shift; + + gisr = gpio_reg_and_bit(&priv->chip, gpio, GISR, &shift); + + raw_spin_lock_irqsave(&priv->lock, flags); + writel(BIT(shift), gisr); + raw_spin_unlock_irqrestore(&priv->lock, flags); +} + +static void tng_irq_unmask_mask(struct tng_gpio *priv, u32 gpio, bool unmask) +{ + unsigned long flags; + void __iomem *gimr; + u32 value; + u8 shift; + + gimr = gpio_reg_and_bit(&priv->chip, gpio, GIMR, &shift); + + raw_spin_lock_irqsave(&priv->lock, flags); + + value = readl(gimr); + if (unmask) + value |= BIT(shift); + else + value &= ~BIT(shift); + writel(value, gimr); + + raw_spin_unlock_irqrestore(&priv->lock, flags); +} + +static void tng_irq_mask(struct irq_data *d) +{ + struct tng_gpio *priv = irq_data_get_irq_chip_data(d); + irq_hw_number_t gpio = irqd_to_hwirq(d); + + tng_irq_unmask_mask(priv, gpio, false); + gpiochip_disable_irq(&priv->chip, gpio); +} + +static void tng_irq_unmask(struct irq_data *d) +{ + struct tng_gpio *priv = irq_data_get_irq_chip_data(d); + irq_hw_number_t gpio = irqd_to_hwirq(d); + + gpiochip_enable_irq(&priv->chip, gpio); + tng_irq_unmask_mask(priv, gpio, true); +} + +static int tng_irq_set_type(struct irq_data *d, unsigned int type) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct tng_gpio *priv = gpiochip_get_data(gc); + irq_hw_number_t gpio = irqd_to_hwirq(d); + void __iomem *grer = gpio_reg(&priv->chip, gpio, GRER); + void __iomem *gfer = gpio_reg(&priv->chip, gpio, GFER); + void __iomem *gitr = gpio_reg(&priv->chip, gpio, GITR); + void __iomem *glpr = gpio_reg(&priv->chip, gpio, GLPR); + u8 shift = gpio % 32; + unsigned long flags; + u32 value; + + raw_spin_lock_irqsave(&priv->lock, flags); + + value = readl(grer); + if (type & IRQ_TYPE_EDGE_RISING) + value |= BIT(shift); + else + value &= ~BIT(shift); + writel(value, grer); + + value = readl(gfer); + if (type & IRQ_TYPE_EDGE_FALLING) + value |= BIT(shift); + else + value &= ~BIT(shift); + writel(value, gfer); + + /* + * To prevent glitches from triggering an unintended level interrupt, + * configure GLPR register first and then configure GITR. + */ + value = readl(glpr); + if (type & IRQ_TYPE_LEVEL_LOW) + value |= BIT(shift); + else + value &= ~BIT(shift); + writel(value, glpr); + + if (type & IRQ_TYPE_LEVEL_MASK) { + value = readl(gitr); + value |= BIT(shift); + writel(value, gitr); + + irq_set_handler_locked(d, handle_level_irq); + } else if (type & IRQ_TYPE_EDGE_BOTH) { + value = readl(gitr); + value &= ~BIT(shift); + writel(value, gitr); + + irq_set_handler_locked(d, handle_edge_irq); + } + + raw_spin_unlock_irqrestore(&priv->lock, flags); + + return 0; +} + +static int tng_irq_set_wake(struct irq_data *d, unsigned int on) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct tng_gpio *priv = gpiochip_get_data(gc); + irq_hw_number_t gpio = irqd_to_hwirq(d); + void __iomem *gwmr = gpio_reg(&priv->chip, gpio, priv->wake_regs.gwmr); + void __iomem *gwsr = gpio_reg(&priv->chip, gpio, priv->wake_regs.gwsr); + u8 shift = gpio % 32; + unsigned long flags; + u32 value; + + raw_spin_lock_irqsave(&priv->lock, flags); + + /* Clear the existing wake status */ + writel(BIT(shift), gwsr); + + value = readl(gwmr); + if (on) + value |= BIT(shift); + else + value &= ~BIT(shift); + writel(value, gwmr); + + raw_spin_unlock_irqrestore(&priv->lock, flags); + + dev_dbg(priv->dev, "%s wake for gpio %lu\n", str_enable_disable(on), gpio); + return 0; +} + +static const struct irq_chip tng_irqchip = { + .name = "gpio-tangier", + .irq_ack = tng_irq_ack, + .irq_mask = tng_irq_mask, + .irq_unmask = tng_irq_unmask, + .irq_set_type = tng_irq_set_type, + .irq_set_wake = tng_irq_set_wake, + .flags = IRQCHIP_IMMUTABLE, + GPIOCHIP_IRQ_RESOURCE_HELPERS, +}; + +static void tng_irq_handler(struct irq_desc *desc) +{ + struct gpio_chip *gc = irq_desc_get_handler_data(desc); + struct tng_gpio *priv = gpiochip_get_data(gc); + struct irq_chip *irqchip = irq_desc_get_chip(desc); + unsigned long base, gpio; + + chained_irq_enter(irqchip, desc); + + /* Check GPIO controller to check which pin triggered the interrupt */ + for (base = 0; base < priv->chip.ngpio; base += 32) { + void __iomem *gisr = gpio_reg(&priv->chip, base, GISR); + void __iomem *gimr = gpio_reg(&priv->chip, base, GIMR); + unsigned long pending, enabled; + + pending = readl(gisr); + enabled = readl(gimr); + + /* Only interrupts that are enabled */ + pending &= enabled; + + for_each_set_bit(gpio, &pending, 32) + generic_handle_domain_irq(gc->irq.domain, base + gpio); + } + + chained_irq_exit(irqchip, desc); +} + +static int tng_irq_init_hw(struct gpio_chip *chip) +{ + struct tng_gpio *priv = gpiochip_get_data(chip); + void __iomem *reg; + unsigned int base; + + for (base = 0; base < priv->chip.ngpio; base += 32) { + /* Clear the rising-edge detect register */ + reg = gpio_reg(&priv->chip, base, GRER); + writel(0, reg); + + /* Clear the falling-edge detect register */ + reg = gpio_reg(&priv->chip, base, GFER); + writel(0, reg); + } + + return 0; +} + +static int tng_gpio_add_pin_ranges(struct gpio_chip *chip) +{ + struct tng_gpio *priv = gpiochip_get_data(chip); + const struct tng_gpio_pinrange *range; + unsigned int i; + int ret; + + for (i = 0; i < priv->pin_info.nranges; i++) { + range = &priv->pin_info.pin_ranges[i]; + ret = gpiochip_add_pin_range(&priv->chip, + priv->pin_info.name, + range->gpio_base, + range->pin_base, + range->npins); + if (ret) { + dev_err(priv->dev, "failed to add GPIO pin range\n"); + return ret; + } + } + + return 0; +} + +int devm_tng_gpio_probe(struct device *dev, struct tng_gpio *gpio) +{ + const struct tng_gpio_info *info = &gpio->info; + struct gpio_irq_chip *girq; + int ret; + + gpio->ctx = devm_kcalloc(dev, DIV_ROUND_UP(info->ngpio, 32), sizeof(*gpio->ctx), GFP_KERNEL); + if (!gpio->ctx) + return -ENOMEM; + + gpio->chip.label = dev_name(dev); + gpio->chip.parent = dev; + gpio->chip.request = gpiochip_generic_request; + gpio->chip.free = gpiochip_generic_free; + gpio->chip.direction_input = tng_gpio_direction_input; + gpio->chip.direction_output = tng_gpio_direction_output; + gpio->chip.get = tng_gpio_get; + gpio->chip.set = tng_gpio_set; + gpio->chip.get_direction = tng_gpio_get_direction; + gpio->chip.set_config = tng_gpio_set_config; + gpio->chip.base = info->base; + gpio->chip.ngpio = info->ngpio; + gpio->chip.can_sleep = false; + gpio->chip.add_pin_ranges = tng_gpio_add_pin_ranges; + + raw_spin_lock_init(&gpio->lock); + + girq = &gpio->chip.irq; + gpio_irq_chip_set_chip(girq, &tng_irqchip); + girq->init_hw = tng_irq_init_hw; + girq->parent_handler = tng_irq_handler; + girq->num_parents = 1; + girq->parents = devm_kcalloc(dev, girq->num_parents, + sizeof(*girq->parents), GFP_KERNEL); + if (!girq->parents) + return -ENOMEM; + + girq->parents[0] = gpio->irq; + girq->first = info->first; + girq->default_type = IRQ_TYPE_NONE; + girq->handler = handle_bad_irq; + + ret = devm_gpiochip_add_data(dev, &gpio->chip, gpio); + if (ret) + return dev_err_probe(dev, ret, "gpiochip_add error\n"); + + return 0; +} +EXPORT_SYMBOL_NS_GPL(devm_tng_gpio_probe, GPIO_TANGIER); + +int tng_gpio_suspend(struct device *dev) +{ + struct tng_gpio *priv = dev_get_drvdata(dev); + struct tng_gpio_context *ctx = priv->ctx; + unsigned long flags; + unsigned int base; + + raw_spin_lock_irqsave(&priv->lock, flags); + + for (base = 0; base < priv->chip.ngpio; base += 32, ctx++) { + /* GPLR is RO, values read will be restored using GPSR */ + ctx->level = readl(gpio_reg(&priv->chip, base, GPLR)); + + ctx->gpdr = readl(gpio_reg(&priv->chip, base, GPDR)); + ctx->grer = readl(gpio_reg(&priv->chip, base, GRER)); + ctx->gfer = readl(gpio_reg(&priv->chip, base, GFER)); + ctx->gimr = readl(gpio_reg(&priv->chip, base, GIMR)); + + ctx->gwmr = readl(gpio_reg(&priv->chip, base, priv->wake_regs.gwmr)); + } + + raw_spin_unlock_irqrestore(&priv->lock, flags); + + return 0; +} +EXPORT_SYMBOL_NS_GPL(tng_gpio_suspend, GPIO_TANGIER); + +int tng_gpio_resume(struct device *dev) +{ + struct tng_gpio *priv = dev_get_drvdata(dev); + struct tng_gpio_context *ctx = priv->ctx; + unsigned long flags; + unsigned int base; + + raw_spin_lock_irqsave(&priv->lock, flags); + + for (base = 0; base < priv->chip.ngpio; base += 32, ctx++) { + /* GPLR is RO, values read will be restored using GPSR */ + writel(ctx->level, gpio_reg(&priv->chip, base, GPSR)); + + writel(ctx->gpdr, gpio_reg(&priv->chip, base, GPDR)); + writel(ctx->grer, gpio_reg(&priv->chip, base, GRER)); + writel(ctx->gfer, gpio_reg(&priv->chip, base, GFER)); + writel(ctx->gimr, gpio_reg(&priv->chip, base, GIMR)); + + writel(ctx->gwmr, gpio_reg(&priv->chip, base, priv->wake_regs.gwmr)); + } + + raw_spin_unlock_irqrestore(&priv->lock, flags); + + return 0; +} +EXPORT_SYMBOL_NS_GPL(tng_gpio_resume, GPIO_TANGIER); + +MODULE_AUTHOR("Andy Shevchenko <[email protected]>"); +MODULE_AUTHOR("Pandith N <[email protected]>"); +MODULE_AUTHOR("Raag Jadav <[email protected]>"); +MODULE_DESCRIPTION("Intel Tangier GPIO driver"); +MODULE_LICENSE("GPL"); |