[PATCH v4 1/2] gpio: mediatek: add driver for MT7621

Sergio Paracuellos
2018-07-05T13:43:10Z

Add driver support for gpio of MT7621 SoC.

Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Reviewed-by: NeilBrown <neil@brown.name>
---
drivers/gpio/Kconfig | 8 ++
drivers/gpio/Makefile | 1 +
drivers/gpio/gpio-mt7621.c | 331 +++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 340 insertions(+)
create mode 100644 drivers/gpio/gpio-mt7621.c

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 71c0ab4..836aa21 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -359,6 +359,14 @@ config GPIO_MPC8XXX
Say Y here if you're going to use hardware that connects to the
MPC512x/831x/834x/837x/8572/8610/QorIQ GPIOs.

+config GPIO_MT7621
+ bool "Mediatek MT7621 GPIO Support"
+ depends on SOC_MT7620 || SOC_MT7621 || COMPILE_TEST
+ select GPIO_GENERIC
+ select GPIOLIB_IRQCHIP
+ help
+ Say yes here to support the Mediatek MT7621 SoC GPIO device
+
config GPIO_MVEBU
def_bool y
depends on PLAT_ORION || ARCH_MVEBU
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 1324c8f..fc77989 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -88,6 +88,7 @@ obj-$(CONFIG_GPIO_MOCKUP) += gpio-mockup.o
obj-$(CONFIG_GPIO_MPC5200) += gpio-mpc5200.o
obj-$(CONFIG_GPIO_MPC8XXX) += gpio-mpc8xxx.o
obj-$(CONFIG_GPIO_MSIC) += gpio-msic.o
+obj-$(CONFIG_GPIO_MT7621) += gpio-mt7621.o
obj-$(CONFIG_GPIO_MVEBU) += gpio-mvebu.o
obj-$(CONFIG_GPIO_MXC) += gpio-mxc.o
obj-$(CONFIG_GPIO_MXS) += gpio-mxs.o
diff --git a/drivers/gpio/gpio-mt7621.c b/drivers/gpio/gpio-mt7621.c
new file mode 100644
index 0000000..d7256b5
--- /dev/null
+++ b/drivers/gpio/gpio-mt7621.c
@@ -0,0 +1,331 @@
+// 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_WIDE 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 gpio_chip chip;
+ spinlock_t lock;
+ int bank;
+ u32 rising;
+ u32 falling;
+ u32 hlevel;
+ u32 llevel;
+};
+
+/**
+ * struct mtk_data - state container for
+ * data of the platform driver. It is 3
+ * separate gpio-chip each one with its
+ * own irq_chip.
+ * @dev: device instance
+ * @gpio_membase: memory base address
+ * @gpio_irq: irq number from the device tree
+ * @gc_map: array of the gpio chips
+ */
+struct mtk_data {
+ struct device *dev;
+ void __iomem *gpio_membase;
+ 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_data *gpio_data = gpiochip_get_data(gc);
+
+ offset = (rg->bank * GPIO_BANK_WIDE) + offset;
+ gc->write_reg(gpio_data->gpio_membase + offset, val);
+}
+
+static inline u32
+mtk_gpio_r32(struct mtk_gc *rg, u32 offset)
+{
+ struct gpio_chip *gc = &rg->chip;
+ struct mtk_data *gpio_data = gpiochip_get_data(gc);
+
+ offset = (rg->bank * GPIO_BANK_WIDE) + offset;
+ return gc->read_reg(gpio_data->gpio_membase + 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 struct irq_chip mediatek_gpio_irq_chip = {
+ .irq_unmask = mediatek_gpio_irq_unmask,
+ .irq_mask = mediatek_gpio_irq_mask,
+ .irq_mask_ack = mediatek_gpio_irq_mask,
+ .irq_set_type = mediatek_gpio_irq_type,
+};
+
+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 platform_device *pdev,
+ struct device_node *node, int bank)
+{
+ struct mtk_data *gpio = dev_get_drvdata(&pdev->dev);
+ struct mtk_gc *rg;
+ void __iomem *dat, *set, *ctrl, *diro;
+ int ret;
+
+ rg = &gpio->gc_map[bank];
+ memset(rg, 0, sizeof(*rg));
+
+ spin_lock_init(&rg->lock);
+ rg->chip.of_node = node;
+ rg->bank = bank;
+
+ dat = gpio->gpio_membase + GPIO_REG_DATA + (rg->bank * GPIO_BANK_WIDE);
+ set = gpio->gpio_membase + GPIO_REG_DSET + (rg->bank * GPIO_BANK_WIDE);
+ ctrl = gpio->gpio_membase + GPIO_REG_DCLR + (rg->bank * GPIO_BANK_WIDE);
+ diro = gpio->gpio_membase + GPIO_REG_CTRL + (rg->bank * GPIO_BANK_WIDE);
+
+ ret = bgpio_init(&rg->chip, &pdev->dev, 4,
+ dat, set, ctrl, diro, NULL, 0);
+ if (ret) {
+ dev_err(&pdev->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(&pdev->dev, GFP_KERNEL, "%s-bank%d",
+ dev_name(&pdev->dev), bank);
+
+ ret = devm_gpiochip_add_data(&pdev->dev, &rg->chip, gpio);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Could not register gpio %d, ret=%d\n",
+ rg->chip.ngpio, ret);
+ return ret;
+ }
+
+ if (gpio->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(&pdev->dev, gpio->gpio_irq,
+ mediatek_gpio_irq_handler, IRQF_SHARED,
+ rg->chip.label, &rg->chip);
+
+ if (ret) {
+ dev_err(&pdev->dev, "Error requesting IRQ %d: %d\n",
+ gpio->gpio_irq, ret);
+ return ret;
+ }
+
+ ret = gpiochip_irqchip_add(&rg->chip, &mediatek_gpio_irq_chip,
+ 0, handle_simple_irq, IRQ_TYPE_NONE);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to add gpiochip_irqchip\n");
+ return ret;
+ }
+
+ gpiochip_set_chained_irqchip(&rg->chip, &mediatek_gpio_irq_chip,
+ gpio->gpio_irq, NULL);
+ }
+
+ /* set polarity to low for all gpios */
+ mtk_gpio_w32(rg, GPIO_REG_POL, 0);
+
+ dev_info(&pdev->dev, "registering %d gpios\n", rg->chip.ngpio);
+
+ return 0;
+}
+
+static int
+mediatek_gpio_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ struct mtk_data *gpio_data;
+ int i;
+
+ gpio_data = devm_kzalloc(&pdev->dev, sizeof(*gpio_data), GFP_KERNEL);
+ if (!gpio_data)
+ return -ENOMEM;
+
+ gpio_data->gpio_membase = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(gpio_data->gpio_membase))
+ return PTR_ERR(gpio_data->gpio_membase);
+
+ gpio_data->gpio_irq = irq_of_parse_and_map(np, 0);
+ gpio_data->dev = &pdev->dev;
+ platform_set_drvdata(pdev, gpio_data);
+ mediatek_gpio_irq_chip.name = dev_name(&pdev->dev);
+
+ for (i = 0; i < MTK_BANK_CNT; i++)
+ mediatek_gpio_bank_probe(pdev, np, i);
+
+ 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);
--
2.7.4