[PATCH v3 3/4] gpio: Add RDA Micro GPIO controller support

From: Manivannan Sadhasivam
Date: Mon Oct 21 2019 - 02:44:44 EST


Add support for GPIO controller from RDA Micro. This GPIO controller
is an in house IP, developed by RDA Micro (now Unisoc) for the use in
RDA88* series of SoCs. There are multiple GPIO ports present in all SoCs,
each capable of addressing 32 GPIOs. But only first 8 pins have the
interrupt capability.

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
---
drivers/gpio/Kconfig | 9 ++
drivers/gpio/Makefile | 1 +
drivers/gpio/gpio-rda.c | 294 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 304 insertions(+)
create mode 100644 drivers/gpio/gpio-rda.c

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 38e096e6925f..a896f0820a21 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -435,6 +435,15 @@ config GPIO_RCAR
help
Say yes here to support GPIO on Renesas R-Car SoCs.

+config GPIO_RDA
+ bool "RDA Micro GPIO controller support"
+ depends on ARCH_RDA || COMPILE_TEST
+ depends on OF_GPIO
+ select GPIO_GENERIC
+ select GPIOLIB_IRQCHIP
+ help
+ Say Y here to support RDA Micro GPIO controller.
+
config GPIO_REG
bool
help
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index d2fd19c15bae..5c68c9a48fa3 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -115,6 +115,7 @@ obj-$(CONFIG_GPIO_PXA) += gpio-pxa.o
obj-$(CONFIG_GPIO_RASPBERRYPI_EXP) += gpio-raspberrypi-exp.o
obj-$(CONFIG_GPIO_RC5T583) += gpio-rc5t583.o
obj-$(CONFIG_GPIO_RCAR) += gpio-rcar.o
+obj-$(CONFIG_GPIO_RDA) += gpio-rda.o
obj-$(CONFIG_GPIO_RDC321X) += gpio-rdc321x.o
obj-$(CONFIG_GPIO_REG) += gpio-reg.o
obj-$(CONFIG_ARCH_SA1100) += gpio-sa1100.o
diff --git a/drivers/gpio/gpio-rda.c b/drivers/gpio/gpio-rda.c
new file mode 100644
index 000000000000..28dcbb58b76b
--- /dev/null
+++ b/drivers/gpio/gpio-rda.c
@@ -0,0 +1,294 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * RDA Micro GPIO driver
+ *
+ * Copyright (C) 2012 RDA Micro Inc.
+ * Copyright (C) 2019 Manivannan Sadhasivam
+ */
+
+#include <linux/bitops.h>
+#include <linux/gpio/driver.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/spinlock.h>
+
+#define RDA_GPIO_OEN_VAL 0x00
+#define RDA_GPIO_OEN_SET_OUT 0x04
+#define RDA_GPIO_OEN_SET_IN 0x08
+#define RDA_GPIO_VAL 0x0c
+#define RDA_GPIO_SET 0x10
+#define RDA_GPIO_CLR 0x14
+#define RDA_GPIO_INT_CTRL_SET 0x18
+#define RDA_GPIO_INT_CTRL_CLR 0x1c
+#define RDA_GPIO_INT_CLR 0x20
+#define RDA_GPIO_INT_STATUS 0x24
+
+#define RDA_GPIO_IRQ_RISE_SHIFT 0
+#define RDA_GPIO_IRQ_FALL_SHIFT 8
+#define RDA_GPIO_DEBOUCE_SHIFT 16
+#define RDA_GPIO_LEVEL_SHIFT 24
+
+#define RDA_GPIO_IRQ_MASK 0xff
+
+/* Each bank consists of 32 GPIOs */
+#define RDA_GPIO_BANK_NR 32
+
+struct rda_gpio {
+ struct gpio_chip chip;
+ void __iomem *base;
+ spinlock_t lock;
+ struct irq_chip irq_chip;
+ int irq;
+};
+
+static inline void rda_gpio_update(struct gpio_chip *chip, unsigned int offset,
+ u16 reg, int val)
+{
+ struct rda_gpio *rda_gpio = gpiochip_get_data(chip);
+ void __iomem *base = rda_gpio->base;
+ unsigned long flags;
+ u32 tmp;
+
+ spin_lock_irqsave(&rda_gpio->lock, flags);
+ tmp = readl_relaxed(base + reg);
+
+ if (val)
+ tmp |= BIT(offset);
+ else
+ tmp &= ~BIT(offset);
+
+ writel_relaxed(tmp, base + reg);
+ spin_unlock_irqrestore(&rda_gpio->lock, flags);
+}
+
+static void rda_gpio_irq_mask(struct irq_data *data)
+{
+ struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
+ struct rda_gpio *rda_gpio = gpiochip_get_data(chip);
+ void __iomem *base = rda_gpio->base;
+ u32 offset = irqd_to_hwirq(data);
+ u32 value;
+
+ value = BIT(offset) << RDA_GPIO_IRQ_RISE_SHIFT;
+ value |= BIT(offset) << RDA_GPIO_IRQ_FALL_SHIFT;
+
+ writel_relaxed(value, base + RDA_GPIO_INT_CTRL_CLR);
+}
+
+static void rda_gpio_irq_ack(struct irq_data *data)
+{
+ struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
+ u32 offset = irqd_to_hwirq(data);
+
+ rda_gpio_update(chip, offset, RDA_GPIO_INT_CLR, 1);
+}
+
+static int rda_gpio_set_irq(struct gpio_chip *chip, u32 offset,
+ unsigned int flow_type)
+{
+ struct rda_gpio *rda_gpio = gpiochip_get_data(chip);
+ void __iomem *base = rda_gpio->base;
+ u32 value;
+
+ switch (flow_type) {
+ case IRQ_TYPE_EDGE_RISING:
+ /* Set rising edge trigger */
+ value = BIT(offset) << RDA_GPIO_IRQ_RISE_SHIFT;
+ writel_relaxed(value, base + RDA_GPIO_INT_CTRL_SET);
+
+ /* Switch to edge trigger interrupt */
+ value = BIT(offset) << RDA_GPIO_LEVEL_SHIFT;
+ writel_relaxed(value, base + RDA_GPIO_INT_CTRL_CLR);
+ break;
+
+ case IRQ_TYPE_EDGE_FALLING:
+ /* Set falling edge trigger */
+ value = BIT(offset) << RDA_GPIO_IRQ_FALL_SHIFT;
+ writel_relaxed(value, base + RDA_GPIO_INT_CTRL_SET);
+
+ /* Switch to edge trigger interrupt */
+ value = BIT(offset) << RDA_GPIO_LEVEL_SHIFT;
+ writel_relaxed(value, base + RDA_GPIO_INT_CTRL_CLR);
+ break;
+
+ case IRQ_TYPE_EDGE_BOTH:
+ /* Set both edge trigger */
+ value = BIT(offset) << RDA_GPIO_IRQ_RISE_SHIFT;
+ value |= BIT(offset) << RDA_GPIO_IRQ_FALL_SHIFT;
+ writel_relaxed(value, base + RDA_GPIO_INT_CTRL_SET);
+
+ /* Switch to edge trigger interrupt */
+ value = BIT(offset) << RDA_GPIO_LEVEL_SHIFT;
+ writel_relaxed(value, base + RDA_GPIO_INT_CTRL_CLR);
+ break;
+
+ case IRQ_TYPE_LEVEL_HIGH:
+ /* Set high level trigger */
+ value = BIT(offset) << RDA_GPIO_IRQ_RISE_SHIFT;
+
+ /* Switch to level trigger interrupt */
+ value |= BIT(offset) << RDA_GPIO_LEVEL_SHIFT;
+ writel_relaxed(value, base + RDA_GPIO_INT_CTRL_SET);
+ break;
+
+ case IRQ_TYPE_LEVEL_LOW:
+ /* Set low level trigger */
+ value = BIT(offset) << RDA_GPIO_IRQ_FALL_SHIFT;
+
+ /* Switch to level trigger interrupt */
+ value |= BIT(offset) << RDA_GPIO_LEVEL_SHIFT;
+ writel_relaxed(value, base + RDA_GPIO_INT_CTRL_SET);
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static void rda_gpio_irq_unmask(struct irq_data *data)
+{
+ struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
+ u32 offset = irqd_to_hwirq(data);
+ u32 trigger = irqd_get_trigger_type(data);
+
+ rda_gpio_set_irq(chip, offset, trigger);
+}
+
+static int rda_gpio_irq_set_type(struct irq_data *data, unsigned int flow_type)
+{
+ struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
+ u32 offset = irqd_to_hwirq(data);
+ int ret;
+
+ ret = rda_gpio_set_irq(chip, offset, flow_type);
+ if (ret)
+ return ret;
+
+ if (flow_type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH))
+ irq_set_handler_locked(data, handle_level_irq);
+ else if (flow_type & (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
+ irq_set_handler_locked(data, handle_edge_irq);
+
+ return 0;
+}
+
+static void rda_gpio_irq_handler(struct irq_desc *desc)
+{
+ struct gpio_chip *chip = irq_desc_get_handler_data(desc);
+ struct irq_chip *ic = irq_desc_get_chip(desc);
+ struct rda_gpio *rda_gpio = gpiochip_get_data(chip);
+ unsigned long status;
+ u32 n, girq;
+
+ chained_irq_enter(ic, desc);
+
+ status = readl_relaxed(rda_gpio->base + RDA_GPIO_INT_STATUS);
+ /* Only lower 8 bits are capable of generating interrupts */
+ status &= RDA_GPIO_IRQ_MASK;
+
+ for_each_set_bit(n, &status, RDA_GPIO_BANK_NR) {
+ girq = irq_find_mapping(chip->irq.domain, n);
+ generic_handle_irq(girq);
+ }
+
+ chained_irq_exit(ic, desc);
+}
+
+static int rda_gpio_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct device *dev = &pdev->dev;
+ struct gpio_irq_chip *girq;
+ struct rda_gpio *rda_gpio;
+ u32 ngpios;
+ int ret;
+
+ rda_gpio = devm_kzalloc(dev, sizeof(*rda_gpio), GFP_KERNEL);
+ if (!rda_gpio)
+ return -ENOMEM;
+
+ ret = device_property_read_u32(dev, "ngpios", &ngpios);
+ if (ret < 0)
+ return ret;
+
+ /*
+ * Not all ports have interrupt capability. For instance, on
+ * RDA8810PL, GPIOC doesn't support interrupt. So we must handle
+ * those also.
+ */
+ rda_gpio->irq = platform_get_irq(pdev, 0);
+
+ rda_gpio->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(rda_gpio->base))
+ return PTR_ERR(rda_gpio->base);
+
+ spin_lock_init(&rda_gpio->lock);
+
+ ret = bgpio_init(&rda_gpio->chip, dev, 4,
+ rda_gpio->base + RDA_GPIO_VAL,
+ rda_gpio->base + RDA_GPIO_SET,
+ rda_gpio->base + RDA_GPIO_CLR,
+ rda_gpio->base + RDA_GPIO_OEN_SET_OUT,
+ rda_gpio->base + RDA_GPIO_OEN_SET_IN,
+ BGPIOF_READ_OUTPUT_REG_SET);
+ if (ret) {
+ dev_err(dev, "bgpio_init failed\n");
+ return ret;
+ }
+
+ rda_gpio->chip.label = dev_name(dev);
+ rda_gpio->chip.ngpio = ngpios;
+ rda_gpio->chip.base = -1;
+ rda_gpio->chip.parent = dev;
+ rda_gpio->chip.of_node = np;
+
+ if (rda_gpio->irq >= 0) {
+ rda_gpio->irq_chip.name = "rda-gpio",
+ rda_gpio->irq_chip.irq_ack = rda_gpio_irq_ack,
+ rda_gpio->irq_chip.irq_mask = rda_gpio_irq_mask,
+ rda_gpio->irq_chip.irq_unmask = rda_gpio_irq_unmask,
+ rda_gpio->irq_chip.irq_set_type = rda_gpio_irq_set_type,
+ rda_gpio->irq_chip.flags = IRQCHIP_SKIP_SET_WAKE,
+
+ girq = &rda_gpio->chip.irq;
+ girq->chip = &rda_gpio->irq_chip;
+ girq->handler = handle_bad_irq;
+ girq->default_type = IRQ_TYPE_NONE;
+ girq->parent_handler = rda_gpio_irq_handler;
+ girq->parent_handler_data = rda_gpio;
+ girq->num_parents = 1;
+ girq->parents = devm_kcalloc(dev, 1,
+ sizeof(*girq->parents),
+ GFP_KERNEL);
+ if (!girq->parents)
+ return -ENOMEM;
+ girq->parents[0] = rda_gpio->irq;
+ }
+
+ platform_set_drvdata(pdev, rda_gpio);
+
+ return devm_gpiochip_add_data(dev, &rda_gpio->chip, rda_gpio);
+}
+
+static const struct of_device_id rda_gpio_of_match[] = {
+ { .compatible = "rda,8810pl-gpio", },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, rda_gpio_of_match);
+
+static struct platform_driver rda_gpio_driver = {
+ .probe = rda_gpio_probe,
+ .driver = {
+ .name = "rda-gpio",
+ .of_match_table = rda_gpio_of_match,
+ },
+};
+
+module_platform_driver_probe(rda_gpio_driver, rda_gpio_probe);
+
+MODULE_DESCRIPTION("RDA Micro GPIO driver");
+MODULE_AUTHOR("Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>");
+MODULE_LICENSE("GPL v2");
--
2.17.1