openwrt/target/linux/ramips/patches-6.6/802-GPIO-MIPS-ralink-add-gp...

276 lines
7.3 KiB
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From: John Crispin <blogic@openwrt.org>
Date: Mon, 4 Aug 2014 20:36:29 +0200
Subject: [PATCH 2/2] GPIO: MIPS: ralink: add gpio driver for ralink SoC
Add gpio driver for Ralink SoC. This driver makes the gpio core on
RT2880, RT305x, rt3352, rt3662, rt3883, rt5350 and mt7620 work.
Signed-off-by: John Crispin <blogic@openwrt.org>
---
drivers/gpio/Kconfig | 8 ++
drivers/gpio/Makefile | 1 +
drivers/gpio/gpio-ralink.c | 230 +++++++++++++++++++++++++++++++++++++
3 files changed, 239 insertions(+)
create mode 100644 drivers/gpio/gpio-ralink.c
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -509,6 +509,14 @@ config GPIO_PXA
help
Say yes here to support the PXA GPIO device.
+config GPIO_RALINK
+ bool "Ralink GPIO Support"
+ depends on SOC_RT288X || SOC_RT305X || SOC_RT3883 || SOC_MT7620
+ select GPIO_GENERIC
+ select GPIOLIB_IRQCHIP
+ help
+ Say yes here to support the Ralink SoC GPIO device
+
config GPIO_RCAR
tristate "Renesas R-Car and RZ/G GPIO support"
depends on ARCH_RENESAS || COMPILE_TEST
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -130,6 +130,7 @@ obj-$(CONFIG_GPIO_PISOSR) += gpio-pisos
obj-$(CONFIG_GPIO_PL061) += gpio-pl061.o
obj-$(CONFIG_GPIO_PMIC_EIC_SPRD) += gpio-pmic-eic-sprd.o
obj-$(CONFIG_GPIO_PXA) += gpio-pxa.o
+obj-$(CONFIG_GPIO_RALINK) += gpio-ralink.o
obj-$(CONFIG_GPIO_RASPBERRYPI_EXP) += gpio-raspberrypi-exp.o
obj-$(CONFIG_GPIO_RC5T583) += gpio-rc5t583.o
obj-$(CONFIG_GPIO_RCAR) += gpio-rcar.o
--- /dev/null
+++ b/drivers/gpio/gpio-ralink.c
@@ -0,0 +1,230 @@
+/*
+ * 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.
+ *
+ * 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/platform_device.h>
+#include <linux/spinlock.h>
+
+enum ralink_gpio_reg {
+ GPIO_REG_INT = 0,
+ GPIO_REG_EDGE,
+ GPIO_REG_RENA,
+ GPIO_REG_FENA,
+ GPIO_REG_DATA,
+ GPIO_REG_DIR,
+ GPIO_REG_POL,
+ GPIO_REG_SET,
+ GPIO_REG_RESET,
+ GPIO_REG_TOGGLE,
+ GPIO_REG_MAX
+};
+
+struct ralink_gpio_chip {
+ struct gpio_chip chip;
+ u8 regs[GPIO_REG_MAX];
+
+ spinlock_t lock;
+ void __iomem *membase;
+ int gpio_irq;
+
+ u32 rising;
+ u32 falling;
+};
+
+static inline void rt_gpio_w32(struct ralink_gpio_chip *rg, u8 reg, u32 val)
+{
+ iowrite32(val, rg->membase + rg->regs[reg]);
+}
+
+static inline u32 rt_gpio_r32(struct ralink_gpio_chip *rg, u8 reg)
+{
+ return ioread32(rg->membase + rg->regs[reg]);
+}
+
+static irqreturn_t ralink_gpio_irq_handler(int irq, void *data)
+{
+ struct gpio_chip *gc = data;
+ struct ralink_gpio_chip *rg = gpiochip_get_data(gc);
+ irqreturn_t ret = IRQ_NONE;
+ unsigned long pending;
+ int bit;
+
+ pending = rt_gpio_r32(rg, GPIO_REG_INT);
+ for_each_set_bit(bit, &pending, rg->chip.ngpio) {
+ generic_handle_domain_irq(gc->irq.domain, bit);
+ rt_gpio_w32(rg, GPIO_REG_INT, BIT(bit));
+ ret |= IRQ_HANDLED;
+ }
+
+ return ret;
+}
+
+static void ralink_gpio_irq_unmask(struct irq_data *d)
+{
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+ struct ralink_gpio_chip *rg = gpiochip_get_data(gc);
+ unsigned long flags;
+ u32 rise, fall;
+
+ rise = rt_gpio_r32(rg, GPIO_REG_RENA);
+ fall = rt_gpio_r32(rg, GPIO_REG_FENA);
+
+ spin_lock_irqsave(&rg->lock, flags);
+ rt_gpio_w32(rg, GPIO_REG_RENA, rise | (BIT(d->hwirq) & rg->rising));
+ rt_gpio_w32(rg, GPIO_REG_FENA, fall | (BIT(d->hwirq) & rg->falling));
+ spin_unlock_irqrestore(&rg->lock, flags);
+}
+
+static void ralink_gpio_irq_mask(struct irq_data *d)
+{
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+ struct ralink_gpio_chip *rg = gpiochip_get_data(gc);
+ unsigned long flags;
+ u32 rise, fall;
+
+ rise = rt_gpio_r32(rg, GPIO_REG_RENA);
+ fall = rt_gpio_r32(rg, GPIO_REG_FENA);
+
+ spin_lock_irqsave(&rg->lock, flags);
+ rt_gpio_w32(rg, GPIO_REG_FENA, fall & ~BIT(d->hwirq));
+ rt_gpio_w32(rg, GPIO_REG_RENA, rise & ~BIT(d->hwirq));
+ spin_unlock_irqrestore(&rg->lock, flags);
+}
+
+static int ralink_gpio_irq_type(struct irq_data *d, unsigned int type)
+{
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+ struct ralink_gpio_chip *rg = gpiochip_get_data(gc);
+ u32 mask = BIT(d->hwirq);
+
+ if (type == IRQ_TYPE_PROBE) {
+ if ((rg->rising | rg->falling) & mask)
+ return 0;
+
+ type = IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING;
+ }
+
+ if (type & IRQ_TYPE_EDGE_RISING)
+ rg->rising |= mask;
+ else
+ rg->rising &= ~mask;
+
+ if (type & IRQ_TYPE_EDGE_FALLING)
+ rg->falling |= mask;
+ else
+ rg->falling &= ~mask;
+
+ return 0;
+}
+
+static struct irq_chip ralink_gpio_irq_chip = {
+ .name = "gpio-ralink",
+ .irq_unmask = ralink_gpio_irq_unmask,
+ .irq_mask = ralink_gpio_irq_mask,
+ .irq_mask_ack = ralink_gpio_irq_mask,
+ .irq_set_type = ralink_gpio_irq_type,
+ .flags = IRQCHIP_IMMUTABLE,
+ GPIOCHIP_IRQ_RESOURCE_HELPERS,
+};
+
+static int ralink_gpio_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ struct ralink_gpio_chip *rg;
+ int ret;
+
+ rg = devm_kzalloc(dev, sizeof(struct ralink_gpio_chip), GFP_KERNEL);
+ if (!rg)
+ return -ENOMEM;
+
+ rg->membase = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(rg->membase))
+ return PTR_ERR(rg->membase);
+
+ if (of_property_read_u8_array(np, "ralink,register-map",
+ rg->regs, GPIO_REG_MAX)) {
+ dev_err(dev, "failed to read register definition\n");
+ return -EINVAL;
+ }
+
+ spin_lock_init(&rg->lock);
+
+ ret = bgpio_init(&rg->chip, dev, 4,
+ rg->membase + rg->regs[GPIO_REG_DATA],
+ rg->membase + rg->regs[GPIO_REG_SET],
+ rg->membase + rg->regs[GPIO_REG_RESET],
+ rg->membase + rg->regs[GPIO_REG_DIR],
+ NULL, 0);
+ if (ret)
+ return dev_err_probe(dev, ret, "bgpio_init() failed\n");
+
+ /* set polarity to low for all lines */
+ rt_gpio_w32(rg, GPIO_REG_POL, 0);
+
+ rg->gpio_irq = platform_get_irq(pdev, 0);
+ if (rg->gpio_irq < 0)
+ return rg->gpio_irq;
+
+ if (rg->gpio_irq) {
+ struct gpio_irq_chip *girq;
+
+ /*
+ * Directly request the irq here instead of passing
+ * a flow-handler because the irq is shared.
+ */
+ ret = devm_request_irq(dev, rg->gpio_irq,
+ ralink_gpio_irq_handler, IRQF_SHARED,
+ NULL, &rg->chip);
+ if (ret) {
+ dev_err(dev, "Error requesting IRQ %d: %d\n",
+ rg->gpio_irq, ret);
+ return ret;
+ }
+
+ girq = &rg->chip.irq;
+ gpio_irq_chip_set_chip(girq, &ralink_gpio_irq_chip);
+ /* This will let us handle the parent IRQ in the driver */
+ girq->parent_handler = NULL;
+ girq->num_parents = 0;
+ girq->parents = NULL;
+ girq->default_type = IRQ_TYPE_NONE;
+ girq->handler = handle_simple_irq;
+
+ rt_gpio_w32(rg, GPIO_REG_RENA, 0);
+ rt_gpio_w32(rg, GPIO_REG_FENA, 0);
+ }
+
+ return devm_gpiochip_add_data(dev, &rg->chip, rg);
+}
+
+static const struct of_device_id ralink_gpio_match[] = {
+ { .compatible = "ralink,rt2880-gpio" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, ralink_gpio_match);
+
+static struct platform_driver ralink_gpio_driver = {
+ .probe = ralink_gpio_probe,
+ .driver = {
+ .name = "ralink_gpio",
+ .of_match_table = ralink_gpio_match,
+ },
+};
+
+static int __init ralink_gpio_init(void)
+{
+ return platform_driver_register(&ralink_gpio_driver);
+}
+
+subsys_initcall(ralink_gpio_init);