diff options
Diffstat (limited to 'drivers/gpio/gpio-mt7621.c')
| -rw-r--r-- | drivers/gpio/gpio-mt7621.c | 338 |
1 files changed, 338 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-mt7621.c b/drivers/gpio/gpio-mt7621.c new file mode 100644 index 000000000..74401e0ad --- /dev/null +++ b/drivers/gpio/gpio-mt7621.c @@ -0,0 +1,338 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2009-2011 Gabor Juhos <juhosg@openwrt.org> + * Copyright (C) 2013 John Crispin <blogic@openwrt.org> + */ + +#include <linux/err.h> +#include <linux/gpio/driver.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of_irq.h> +#include <linux/platform_device.h> +#include <linux/spinlock.h> + +#define MTK_BANK_CNT 3 +#define MTK_BANK_WIDTH 32 + +#define GPIO_BANK_STRIDE 0x04 +#define GPIO_REG_CTRL 0x00 +#define GPIO_REG_POL 0x10 +#define GPIO_REG_DATA 0x20 +#define GPIO_REG_DSET 0x30 +#define GPIO_REG_DCLR 0x40 +#define GPIO_REG_REDGE 0x50 +#define GPIO_REG_FEDGE 0x60 +#define GPIO_REG_HLVL 0x70 +#define GPIO_REG_LLVL 0x80 +#define GPIO_REG_STAT 0x90 +#define GPIO_REG_EDGE 0xA0 + +struct mtk_gc { + struct irq_chip irq_chip; + struct gpio_chip chip; + spinlock_t lock; + int bank; + u32 rising; + u32 falling; + u32 hlevel; + u32 llevel; +}; + +/** + * struct mtk - state container for + * data of the platform driver. It is 3 + * separate gpio-chip each one with its + * own irq_chip. + * @dev: device instance + * @base: memory base address + * @gpio_irq: irq number from the device tree + * @gc_map: array of the gpio chips + */ +struct mtk { + struct device *dev; + void __iomem *base; + int gpio_irq; + struct mtk_gc gc_map[MTK_BANK_CNT]; +}; + +static inline struct mtk_gc * +to_mediatek_gpio(struct gpio_chip *chip) +{ + return container_of(chip, struct mtk_gc, chip); +} + +static inline void +mtk_gpio_w32(struct mtk_gc *rg, u32 offset, u32 val) +{ + struct gpio_chip *gc = &rg->chip; + struct mtk *mtk = gpiochip_get_data(gc); + + offset = (rg->bank * GPIO_BANK_STRIDE) + offset; + gc->write_reg(mtk->base + offset, val); +} + +static inline u32 +mtk_gpio_r32(struct mtk_gc *rg, u32 offset) +{ + struct gpio_chip *gc = &rg->chip; + struct mtk *mtk = gpiochip_get_data(gc); + + offset = (rg->bank * GPIO_BANK_STRIDE) + offset; + return gc->read_reg(mtk->base + offset); +} + +static irqreturn_t +mediatek_gpio_irq_handler(int irq, void *data) +{ + struct gpio_chip *gc = data; + struct mtk_gc *rg = to_mediatek_gpio(gc); + irqreturn_t ret = IRQ_NONE; + unsigned long pending; + int bit; + + pending = mtk_gpio_r32(rg, GPIO_REG_STAT); + + for_each_set_bit(bit, &pending, MTK_BANK_WIDTH) { + u32 map = irq_find_mapping(gc->irq.domain, bit); + + generic_handle_irq(map); + mtk_gpio_w32(rg, GPIO_REG_STAT, BIT(bit)); + ret |= IRQ_HANDLED; + } + + return ret; +} + +static void +mediatek_gpio_irq_unmask(struct irq_data *d) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct mtk_gc *rg = to_mediatek_gpio(gc); + int pin = d->hwirq; + unsigned long flags; + u32 rise, fall, high, low; + + spin_lock_irqsave(&rg->lock, flags); + rise = mtk_gpio_r32(rg, GPIO_REG_REDGE); + fall = mtk_gpio_r32(rg, GPIO_REG_FEDGE); + high = mtk_gpio_r32(rg, GPIO_REG_HLVL); + low = mtk_gpio_r32(rg, GPIO_REG_LLVL); + mtk_gpio_w32(rg, GPIO_REG_REDGE, rise | (BIT(pin) & rg->rising)); + mtk_gpio_w32(rg, GPIO_REG_FEDGE, fall | (BIT(pin) & rg->falling)); + mtk_gpio_w32(rg, GPIO_REG_HLVL, high | (BIT(pin) & rg->hlevel)); + mtk_gpio_w32(rg, GPIO_REG_LLVL, low | (BIT(pin) & rg->llevel)); + spin_unlock_irqrestore(&rg->lock, flags); +} + +static void +mediatek_gpio_irq_mask(struct irq_data *d) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct mtk_gc *rg = to_mediatek_gpio(gc); + int pin = d->hwirq; + unsigned long flags; + u32 rise, fall, high, low; + + spin_lock_irqsave(&rg->lock, flags); + rise = mtk_gpio_r32(rg, GPIO_REG_REDGE); + fall = mtk_gpio_r32(rg, GPIO_REG_FEDGE); + high = mtk_gpio_r32(rg, GPIO_REG_HLVL); + low = mtk_gpio_r32(rg, GPIO_REG_LLVL); + mtk_gpio_w32(rg, GPIO_REG_FEDGE, fall & ~BIT(pin)); + mtk_gpio_w32(rg, GPIO_REG_REDGE, rise & ~BIT(pin)); + mtk_gpio_w32(rg, GPIO_REG_HLVL, high & ~BIT(pin)); + mtk_gpio_w32(rg, GPIO_REG_LLVL, low & ~BIT(pin)); + spin_unlock_irqrestore(&rg->lock, flags); +} + +static int +mediatek_gpio_irq_type(struct irq_data *d, unsigned int type) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct mtk_gc *rg = to_mediatek_gpio(gc); + int pin = d->hwirq; + u32 mask = BIT(pin); + + if (type == IRQ_TYPE_PROBE) { + if ((rg->rising | rg->falling | + rg->hlevel | rg->llevel) & mask) + return 0; + + type = IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING; + } + + rg->rising &= ~mask; + rg->falling &= ~mask; + rg->hlevel &= ~mask; + rg->llevel &= ~mask; + + switch (type & IRQ_TYPE_SENSE_MASK) { + case IRQ_TYPE_EDGE_BOTH: + rg->rising |= mask; + rg->falling |= mask; + break; + case IRQ_TYPE_EDGE_RISING: + rg->rising |= mask; + break; + case IRQ_TYPE_EDGE_FALLING: + rg->falling |= mask; + break; + case IRQ_TYPE_LEVEL_HIGH: + rg->hlevel |= mask; + break; + case IRQ_TYPE_LEVEL_LOW: + rg->llevel |= mask; + break; + } + + return 0; +} + +static int +mediatek_gpio_xlate(struct gpio_chip *chip, + const struct of_phandle_args *spec, u32 *flags) +{ + int gpio = spec->args[0]; + struct mtk_gc *rg = to_mediatek_gpio(chip); + + if (rg->bank != gpio / MTK_BANK_WIDTH) + return -EINVAL; + + if (flags) + *flags = spec->args[1]; + + return gpio % MTK_BANK_WIDTH; +} + +static int +mediatek_gpio_bank_probe(struct device *dev, + struct device_node *node, int bank) +{ + struct mtk *mtk = dev_get_drvdata(dev); + struct mtk_gc *rg; + void __iomem *dat, *set, *ctrl, *diro; + int ret; + + rg = &mtk->gc_map[bank]; + memset(rg, 0, sizeof(*rg)); + + spin_lock_init(&rg->lock); + rg->chip.of_node = node; + rg->bank = bank; + + dat = mtk->base + GPIO_REG_DATA + (rg->bank * GPIO_BANK_STRIDE); + set = mtk->base + GPIO_REG_DSET + (rg->bank * GPIO_BANK_STRIDE); + ctrl = mtk->base + GPIO_REG_DCLR + (rg->bank * GPIO_BANK_STRIDE); + diro = mtk->base + GPIO_REG_CTRL + (rg->bank * GPIO_BANK_STRIDE); + + ret = bgpio_init(&rg->chip, dev, 4, + dat, set, ctrl, diro, NULL, 0); + if (ret) { + dev_err(dev, "bgpio_init() failed\n"); + return ret; + } + + rg->chip.of_gpio_n_cells = 2; + rg->chip.of_xlate = mediatek_gpio_xlate; + rg->chip.label = devm_kasprintf(dev, GFP_KERNEL, "%s-bank%d", + dev_name(dev), bank); + if (!rg->chip.label) + return -ENOMEM; + + ret = devm_gpiochip_add_data(dev, &rg->chip, mtk); + if (ret < 0) { + dev_err(dev, "Could not register gpio %d, ret=%d\n", + rg->chip.ngpio, ret); + return ret; + } + + rg->irq_chip.name = dev_name(dev); + rg->irq_chip.parent_device = dev; + rg->irq_chip.irq_unmask = mediatek_gpio_irq_unmask; + rg->irq_chip.irq_mask = mediatek_gpio_irq_mask; + rg->irq_chip.irq_mask_ack = mediatek_gpio_irq_mask; + rg->irq_chip.irq_set_type = mediatek_gpio_irq_type; + + if (mtk->gpio_irq) { + /* + * Manually request the irq here instead of passing + * a flow-handler to gpiochip_set_chained_irqchip, + * because the irq is shared. + */ + ret = devm_request_irq(dev, mtk->gpio_irq, + mediatek_gpio_irq_handler, IRQF_SHARED, + rg->chip.label, &rg->chip); + + if (ret) { + dev_err(dev, "Error requesting IRQ %d: %d\n", + mtk->gpio_irq, ret); + return ret; + } + + ret = gpiochip_irqchip_add(&rg->chip, &rg->irq_chip, + 0, handle_simple_irq, IRQ_TYPE_NONE); + if (ret) { + dev_err(dev, "failed to add gpiochip_irqchip\n"); + return ret; + } + + gpiochip_set_chained_irqchip(&rg->chip, &rg->irq_chip, + mtk->gpio_irq, NULL); + } + + /* set polarity to low for all gpios */ + mtk_gpio_w32(rg, GPIO_REG_POL, 0); + + dev_info(dev, "registering %d gpios\n", rg->chip.ngpio); + + return 0; +} + +static int +mediatek_gpio_probe(struct platform_device *pdev) +{ + struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + struct device *dev = &pdev->dev; + struct device_node *np = dev->of_node; + struct mtk *mtk; + int i; + int ret; + + mtk = devm_kzalloc(dev, sizeof(*mtk), GFP_KERNEL); + if (!mtk) + return -ENOMEM; + + mtk->base = devm_ioremap_resource(dev, res); + if (IS_ERR(mtk->base)) + return PTR_ERR(mtk->base); + + mtk->gpio_irq = irq_of_parse_and_map(np, 0); + mtk->dev = dev; + platform_set_drvdata(pdev, mtk); + + for (i = 0; i < MTK_BANK_CNT; i++) { + ret = mediatek_gpio_bank_probe(dev, np, i); + if (ret) + return ret; + } + + return 0; +} + +static const struct of_device_id mediatek_gpio_match[] = { + { .compatible = "mediatek,mt7621-gpio" }, + {}, +}; +MODULE_DEVICE_TABLE(of, mediatek_gpio_match); + +static struct platform_driver mediatek_gpio_driver = { + .probe = mediatek_gpio_probe, + .driver = { + .name = "mt7621_gpio", + .of_match_table = mediatek_gpio_match, + }, +}; + +builtin_platform_driver(mediatek_gpio_driver); |