diff options
Diffstat (limited to 'drivers/gpio/gpio-uniphier.c')
| -rw-r--r-- | drivers/gpio/gpio-uniphier.c | 510 |
1 files changed, 510 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-uniphier.c b/drivers/gpio/gpio-uniphier.c new file mode 100644 index 000000000..c72ec3ddf --- /dev/null +++ b/drivers/gpio/gpio-uniphier.c @@ -0,0 +1,510 @@ +/* + * Copyright (C) 2017 Socionext Inc. + * Author: Masahiro Yamada <yamada.masahiro@socionext.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. + */ + +#include <linux/bitops.h> +#include <linux/gpio/driver.h> +#include <linux/irq.h> +#include <linux/irqdomain.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/of_irq.h> +#include <linux/platform_device.h> +#include <linux/spinlock.h> +#include <dt-bindings/gpio/uniphier-gpio.h> + +#define UNIPHIER_GPIO_BANK_MASK \ + GENMASK((UNIPHIER_GPIO_LINES_PER_BANK) - 1, 0) + +#define UNIPHIER_GPIO_IRQ_MAX_NUM 24 + +#define UNIPHIER_GPIO_PORT_DATA 0x0 /* data */ +#define UNIPHIER_GPIO_PORT_DIR 0x4 /* direction (1:in, 0:out) */ +#define UNIPHIER_GPIO_IRQ_EN 0x90 /* irq enable */ +#define UNIPHIER_GPIO_IRQ_MODE 0x94 /* irq mode (1: both edge) */ +#define UNIPHIER_GPIO_IRQ_FLT_EN 0x98 /* noise filter enable */ +#define UNIPHIER_GPIO_IRQ_FLT_CYC 0x9c /* noise filter clock cycle */ + +struct uniphier_gpio_priv { + struct gpio_chip chip; + struct irq_chip irq_chip; + struct irq_domain *domain; + void __iomem *regs; + spinlock_t lock; + u32 saved_vals[0]; +}; + +static unsigned int uniphier_gpio_bank_to_reg(unsigned int bank) +{ + unsigned int reg; + + reg = (bank + 1) * 8; + + /* + * Unfortunately, the GPIO port registers are not contiguous because + * offset 0x90-0x9f is used for IRQ. Add 0x10 when crossing the region. + */ + if (reg >= UNIPHIER_GPIO_IRQ_EN) + reg += 0x10; + + return reg; +} + +static void uniphier_gpio_get_bank_and_mask(unsigned int offset, + unsigned int *bank, u32 *mask) +{ + *bank = offset / UNIPHIER_GPIO_LINES_PER_BANK; + *mask = BIT(offset % UNIPHIER_GPIO_LINES_PER_BANK); +} + +static void uniphier_gpio_reg_update(struct uniphier_gpio_priv *priv, + unsigned int reg, u32 mask, u32 val) +{ + unsigned long flags; + u32 tmp; + + spin_lock_irqsave(&priv->lock, flags); + tmp = readl(priv->regs + reg); + tmp &= ~mask; + tmp |= mask & val; + writel(tmp, priv->regs + reg); + spin_unlock_irqrestore(&priv->lock, flags); +} + +static void uniphier_gpio_bank_write(struct gpio_chip *chip, unsigned int bank, + unsigned int reg, u32 mask, u32 val) +{ + struct uniphier_gpio_priv *priv = gpiochip_get_data(chip); + + if (!mask) + return; + + uniphier_gpio_reg_update(priv, uniphier_gpio_bank_to_reg(bank) + reg, + mask, val); +} + +static void uniphier_gpio_offset_write(struct gpio_chip *chip, + unsigned int offset, unsigned int reg, + int val) +{ + unsigned int bank; + u32 mask; + + uniphier_gpio_get_bank_and_mask(offset, &bank, &mask); + + uniphier_gpio_bank_write(chip, bank, reg, mask, val ? mask : 0); +} + +static int uniphier_gpio_offset_read(struct gpio_chip *chip, + unsigned int offset, unsigned int reg) +{ + struct uniphier_gpio_priv *priv = gpiochip_get_data(chip); + unsigned int bank, reg_offset; + u32 mask; + + uniphier_gpio_get_bank_and_mask(offset, &bank, &mask); + reg_offset = uniphier_gpio_bank_to_reg(bank) + reg; + + return !!(readl(priv->regs + reg_offset) & mask); +} + +static int uniphier_gpio_get_direction(struct gpio_chip *chip, + unsigned int offset) +{ + return uniphier_gpio_offset_read(chip, offset, UNIPHIER_GPIO_PORT_DIR); +} + +static int uniphier_gpio_direction_input(struct gpio_chip *chip, + unsigned int offset) +{ + uniphier_gpio_offset_write(chip, offset, UNIPHIER_GPIO_PORT_DIR, 1); + + return 0; +} + +static int uniphier_gpio_direction_output(struct gpio_chip *chip, + unsigned int offset, int val) +{ + uniphier_gpio_offset_write(chip, offset, UNIPHIER_GPIO_PORT_DATA, val); + uniphier_gpio_offset_write(chip, offset, UNIPHIER_GPIO_PORT_DIR, 0); + + return 0; +} + +static int uniphier_gpio_get(struct gpio_chip *chip, unsigned int offset) +{ + return uniphier_gpio_offset_read(chip, offset, UNIPHIER_GPIO_PORT_DATA); +} + +static void uniphier_gpio_set(struct gpio_chip *chip, + unsigned int offset, int val) +{ + uniphier_gpio_offset_write(chip, offset, UNIPHIER_GPIO_PORT_DATA, val); +} + +static void uniphier_gpio_set_multiple(struct gpio_chip *chip, + unsigned long *mask, unsigned long *bits) +{ + unsigned int bank, shift, bank_mask, bank_bits; + int i; + + for (i = 0; i < chip->ngpio; i += UNIPHIER_GPIO_LINES_PER_BANK) { + bank = i / UNIPHIER_GPIO_LINES_PER_BANK; + shift = i % BITS_PER_LONG; + bank_mask = (mask[BIT_WORD(i)] >> shift) & + UNIPHIER_GPIO_BANK_MASK; + bank_bits = bits[BIT_WORD(i)] >> shift; + + uniphier_gpio_bank_write(chip, bank, UNIPHIER_GPIO_PORT_DATA, + bank_mask, bank_bits); + } +} + +static int uniphier_gpio_to_irq(struct gpio_chip *chip, unsigned int offset) +{ + struct irq_fwspec fwspec; + + if (offset < UNIPHIER_GPIO_IRQ_OFFSET) + return -ENXIO; + + fwspec.fwnode = of_node_to_fwnode(chip->parent->of_node); + fwspec.param_count = 2; + fwspec.param[0] = offset - UNIPHIER_GPIO_IRQ_OFFSET; + /* + * IRQ_TYPE_NONE is rejected by the parent irq domain. Set LEVEL_HIGH + * temporarily. Anyway, ->irq_set_type() will override it later. + */ + fwspec.param[1] = IRQ_TYPE_LEVEL_HIGH; + + return irq_create_fwspec_mapping(&fwspec); +} + +static void uniphier_gpio_irq_mask(struct irq_data *data) +{ + struct uniphier_gpio_priv *priv = data->chip_data; + u32 mask = BIT(data->hwirq); + + uniphier_gpio_reg_update(priv, UNIPHIER_GPIO_IRQ_EN, mask, 0); + + irq_chip_mask_parent(data); +} + +static void uniphier_gpio_irq_unmask(struct irq_data *data) +{ + struct uniphier_gpio_priv *priv = data->chip_data; + u32 mask = BIT(data->hwirq); + + uniphier_gpio_reg_update(priv, UNIPHIER_GPIO_IRQ_EN, mask, mask); + + irq_chip_unmask_parent(data); +} + +static int uniphier_gpio_irq_set_type(struct irq_data *data, unsigned int type) +{ + struct uniphier_gpio_priv *priv = data->chip_data; + u32 mask = BIT(data->hwirq); + u32 val = 0; + + if (type == IRQ_TYPE_EDGE_BOTH) { + val = mask; + type = IRQ_TYPE_EDGE_FALLING; + } + + uniphier_gpio_reg_update(priv, UNIPHIER_GPIO_IRQ_MODE, mask, val); + /* To enable both edge detection, the noise filter must be enabled. */ + uniphier_gpio_reg_update(priv, UNIPHIER_GPIO_IRQ_FLT_EN, mask, val); + + return irq_chip_set_type_parent(data, type); +} + +static int uniphier_gpio_irq_get_parent_hwirq(struct uniphier_gpio_priv *priv, + unsigned int hwirq) +{ + struct device_node *np = priv->chip.parent->of_node; + const __be32 *range; + u32 base, parent_base, size; + int len; + + range = of_get_property(np, "socionext,interrupt-ranges", &len); + if (!range) + return -EINVAL; + + len /= sizeof(*range); + + for (; len >= 3; len -= 3) { + base = be32_to_cpu(*range++); + parent_base = be32_to_cpu(*range++); + size = be32_to_cpu(*range++); + + if (base <= hwirq && hwirq < base + size) + return hwirq - base + parent_base; + } + + return -ENOENT; +} + +static int uniphier_gpio_irq_domain_translate(struct irq_domain *domain, + struct irq_fwspec *fwspec, + unsigned long *out_hwirq, + unsigned int *out_type) +{ + if (WARN_ON(fwspec->param_count < 2)) + return -EINVAL; + + *out_hwirq = fwspec->param[0]; + *out_type = fwspec->param[1] & IRQ_TYPE_SENSE_MASK; + + return 0; +} + +static int uniphier_gpio_irq_domain_alloc(struct irq_domain *domain, + unsigned int virq, + unsigned int nr_irqs, void *arg) +{ + struct uniphier_gpio_priv *priv = domain->host_data; + struct irq_fwspec parent_fwspec; + irq_hw_number_t hwirq; + unsigned int type; + int ret; + + if (WARN_ON(nr_irqs != 1)) + return -EINVAL; + + ret = uniphier_gpio_irq_domain_translate(domain, arg, &hwirq, &type); + if (ret) + return ret; + + ret = uniphier_gpio_irq_get_parent_hwirq(priv, hwirq); + if (ret < 0) + return ret; + + /* parent is UniPhier AIDET */ + parent_fwspec.fwnode = domain->parent->fwnode; + parent_fwspec.param_count = 2; + parent_fwspec.param[0] = ret; + parent_fwspec.param[1] = (type == IRQ_TYPE_EDGE_BOTH) ? + IRQ_TYPE_EDGE_FALLING : type; + + ret = irq_domain_set_hwirq_and_chip(domain, virq, hwirq, + &priv->irq_chip, priv); + if (ret) + return ret; + + return irq_domain_alloc_irqs_parent(domain, virq, 1, &parent_fwspec); +} + +static int uniphier_gpio_irq_domain_activate(struct irq_domain *domain, + struct irq_data *data, bool early) +{ + struct uniphier_gpio_priv *priv = domain->host_data; + struct gpio_chip *chip = &priv->chip; + + return gpiochip_lock_as_irq(chip, data->hwirq + UNIPHIER_GPIO_IRQ_OFFSET); +} + +static void uniphier_gpio_irq_domain_deactivate(struct irq_domain *domain, + struct irq_data *data) +{ + struct uniphier_gpio_priv *priv = domain->host_data; + struct gpio_chip *chip = &priv->chip; + + gpiochip_unlock_as_irq(chip, data->hwirq + UNIPHIER_GPIO_IRQ_OFFSET); +} + +static const struct irq_domain_ops uniphier_gpio_irq_domain_ops = { + .alloc = uniphier_gpio_irq_domain_alloc, + .free = irq_domain_free_irqs_common, + .activate = uniphier_gpio_irq_domain_activate, + .deactivate = uniphier_gpio_irq_domain_deactivate, + .translate = uniphier_gpio_irq_domain_translate, +}; + +static void uniphier_gpio_hw_init(struct uniphier_gpio_priv *priv) +{ + /* + * Due to the hardware design, the noise filter must be enabled to + * detect both edge interrupts. This filter is intended to remove the + * noise from the irq lines. It does not work for GPIO input, so GPIO + * debounce is not supported. Unfortunately, the filter period is + * shared among all irq lines. Just choose a sensible period here. + */ + writel(0xff, priv->regs + UNIPHIER_GPIO_IRQ_FLT_CYC); +} + +static unsigned int uniphier_gpio_get_nbanks(unsigned int ngpio) +{ + return DIV_ROUND_UP(ngpio, UNIPHIER_GPIO_LINES_PER_BANK); +} + +static int uniphier_gpio_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct device_node *parent_np; + struct irq_domain *parent_domain; + struct uniphier_gpio_priv *priv; + struct gpio_chip *chip; + struct irq_chip *irq_chip; + struct resource *regs; + unsigned int nregs; + u32 ngpios; + int ret; + + parent_np = of_irq_find_parent(dev->of_node); + if (!parent_np) + return -ENXIO; + + parent_domain = irq_find_host(parent_np); + of_node_put(parent_np); + if (!parent_domain) + return -EPROBE_DEFER; + + ret = of_property_read_u32(dev->of_node, "ngpios", &ngpios); + if (ret) + return ret; + + nregs = uniphier_gpio_get_nbanks(ngpios) * 2 + 3; + priv = devm_kzalloc(dev, struct_size(priv, saved_vals, nregs), + GFP_KERNEL); + if (!priv) + return -ENOMEM; + + regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); + priv->regs = devm_ioremap_resource(dev, regs); + if (IS_ERR(priv->regs)) + return PTR_ERR(priv->regs); + + spin_lock_init(&priv->lock); + + chip = &priv->chip; + chip->label = dev_name(dev); + chip->parent = dev; + chip->request = gpiochip_generic_request; + chip->free = gpiochip_generic_free; + chip->get_direction = uniphier_gpio_get_direction; + chip->direction_input = uniphier_gpio_direction_input; + chip->direction_output = uniphier_gpio_direction_output; + chip->get = uniphier_gpio_get; + chip->set = uniphier_gpio_set; + chip->set_multiple = uniphier_gpio_set_multiple; + chip->to_irq = uniphier_gpio_to_irq; + chip->base = -1; + chip->ngpio = ngpios; + + irq_chip = &priv->irq_chip; + irq_chip->name = dev_name(dev); + irq_chip->irq_mask = uniphier_gpio_irq_mask; + irq_chip->irq_unmask = uniphier_gpio_irq_unmask; + irq_chip->irq_eoi = irq_chip_eoi_parent; + irq_chip->irq_set_affinity = irq_chip_set_affinity_parent; + irq_chip->irq_set_type = uniphier_gpio_irq_set_type; + + uniphier_gpio_hw_init(priv); + + ret = devm_gpiochip_add_data(dev, chip, priv); + if (ret) + return ret; + + priv->domain = irq_domain_create_hierarchy( + parent_domain, 0, + UNIPHIER_GPIO_IRQ_MAX_NUM, + of_node_to_fwnode(dev->of_node), + &uniphier_gpio_irq_domain_ops, priv); + if (!priv->domain) + return -ENOMEM; + + platform_set_drvdata(pdev, priv); + + return 0; +} + +static int uniphier_gpio_remove(struct platform_device *pdev) +{ + struct uniphier_gpio_priv *priv = platform_get_drvdata(pdev); + + irq_domain_remove(priv->domain); + + return 0; +} + +static int __maybe_unused uniphier_gpio_suspend(struct device *dev) +{ + struct uniphier_gpio_priv *priv = dev_get_drvdata(dev); + unsigned int nbanks = uniphier_gpio_get_nbanks(priv->chip.ngpio); + u32 *val = priv->saved_vals; + unsigned int reg; + int i; + + for (i = 0; i < nbanks; i++) { + reg = uniphier_gpio_bank_to_reg(i); + + *val++ = readl(priv->regs + reg + UNIPHIER_GPIO_PORT_DATA); + *val++ = readl(priv->regs + reg + UNIPHIER_GPIO_PORT_DIR); + } + + *val++ = readl(priv->regs + UNIPHIER_GPIO_IRQ_EN); + *val++ = readl(priv->regs + UNIPHIER_GPIO_IRQ_MODE); + *val++ = readl(priv->regs + UNIPHIER_GPIO_IRQ_FLT_EN); + + return 0; +} + +static int __maybe_unused uniphier_gpio_resume(struct device *dev) +{ + struct uniphier_gpio_priv *priv = dev_get_drvdata(dev); + unsigned int nbanks = uniphier_gpio_get_nbanks(priv->chip.ngpio); + const u32 *val = priv->saved_vals; + unsigned int reg; + int i; + + for (i = 0; i < nbanks; i++) { + reg = uniphier_gpio_bank_to_reg(i); + + writel(*val++, priv->regs + reg + UNIPHIER_GPIO_PORT_DATA); + writel(*val++, priv->regs + reg + UNIPHIER_GPIO_PORT_DIR); + } + + writel(*val++, priv->regs + UNIPHIER_GPIO_IRQ_EN); + writel(*val++, priv->regs + UNIPHIER_GPIO_IRQ_MODE); + writel(*val++, priv->regs + UNIPHIER_GPIO_IRQ_FLT_EN); + + uniphier_gpio_hw_init(priv); + + return 0; +} + +static const struct dev_pm_ops uniphier_gpio_pm_ops = { + SET_LATE_SYSTEM_SLEEP_PM_OPS(uniphier_gpio_suspend, + uniphier_gpio_resume) +}; + +static const struct of_device_id uniphier_gpio_match[] = { + { .compatible = "socionext,uniphier-gpio" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, uniphier_gpio_match); + +static struct platform_driver uniphier_gpio_driver = { + .probe = uniphier_gpio_probe, + .remove = uniphier_gpio_remove, + .driver = { + .name = "uniphier-gpio", + .of_match_table = uniphier_gpio_match, + .pm = &uniphier_gpio_pm_ops, + }, +}; +module_platform_driver(uniphier_gpio_driver); + +MODULE_AUTHOR("Masahiro Yamada <yamada.masahiro@socionext.com>"); +MODULE_DESCRIPTION("UniPhier GPIO driver"); +MODULE_LICENSE("GPL v2"); |