[PATCH v3 1/1] gpio: mpfs: add polarfire soc gpio support

lewis.hanly
2022-07-16T07:11:50Z

From: Lewis Hanly <lewis.hanly@microchip.com>

Add a driver to support the Polarfire SoC gpio controller.

Signed-off-by: Lewis Hanly <lewis.hanly@microchip.com>
---
drivers/gpio/Kconfig | 9 +
drivers/gpio/Makefile | 1 +
drivers/gpio/gpio-mpfs.c | 361 +++++++++++++++++++++++++++++++++++++++
3 files changed, 371 insertions(+)
create mode 100644 drivers/gpio/gpio-mpfs.c

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index b01961999ced..86b1e5557482 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -490,6 +490,15 @@ config GPIO_PMIC_EIC_SPRD
help
Say yes here to support Spreadtrum PMIC EIC device.

+config GPIO_POLARFIRE_SOC
+ bool "Microchip FPGA GPIO support"
+ depends on OF_GPIO
+ select IRQ_DOMAIN_HIERARCHY
+ select GPIOLIB_IRQCHIP
+ select GPIO_GENERIC
+ help
+ Say yes here to support the GPIO device on Microchip FPGAs.
+
config GPIO_PXA
bool "PXA GPIO support"
depends on ARCH_PXA || ARCH_MMP || COMPILE_TEST
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 14352f6dfe8e..3b8b6703e593 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -119,6 +119,7 @@ obj-$(CONFIG_GPIO_PCI_IDIO_16) += gpio-pci-idio-16.o
obj-$(CONFIG_GPIO_PISOSR) += gpio-pisosr.o
obj-$(CONFIG_GPIO_PL061) += gpio-pl061.o
obj-$(CONFIG_GPIO_PMIC_EIC_SPRD) += gpio-pmic-eic-sprd.o
+obj-$(CONFIG_GPIO_POLARFIRE_SOC) += gpio-mpfs.o
obj-$(CONFIG_GPIO_PXA) += gpio-pxa.o
obj-$(CONFIG_GPIO_RASPBERRYPI_EXP) += gpio-raspberrypi-exp.o
obj-$(CONFIG_GPIO_RC5T583) += gpio-rc5t583.o
diff --git a/drivers/gpio/gpio-mpfs.c b/drivers/gpio/gpio-mpfs.c
new file mode 100644
index 000000000000..5806abc5cfb8
--- /dev/null
+++ b/drivers/gpio/gpio-mpfs.c
@@ -0,0 +1,361 @@
+// SPDX-License-Identifier: (GPL-2.0)
+/*
+ * Microchip PolarFire SoC (MPFS) GPIO controller driver
+ *
+ * Copyright (c) 2018-2022 Microchip Technology Inc. and its subsidiaries
+ *
+ * Author: Lewis Hanly <lewis.hanly@microchip.com>
+ */
+
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/device.h>
+#include <linux/gpio/driver.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/irq.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/mod_devicetable.h>
+#include <linux/platform_device.h>
+#include <linux/spinlock.h>
+
+#define MPFS_GPIO_CTRL(i) (0x4 * (i))
+#define NUM_GPIO 32
+#define MPFS_GPIO_EN_INT 3
+#define MPFS_GPIO_EN_OUT_BUF BIT(2)
+#define MPFS_GPIO_EN_IN BIT(1)
+#define MPFS_GPIO_EN_OUT BIT(0)
+
+#define MPFS_GPIO_TYPE_INT_EDGE_BOTH 0x80
+#define MPFS_GPIO_TYPE_INT_EDGE_NEG 0x60
+#define MPFS_GPIO_TYPE_INT_EDGE_POS 0x40
+#define MPFS_GPIO_TYPE_INT_LEVEL_LOW 0x20
+#define MPFS_GPIO_TYPE_INT_LEVEL_HIGH 0x00
+#define MPFS_GPIO_TYPE_INT_MASK GENMASK(7, 5)
+#define MPFS_IRQ_REG 0x80
+#define MPFS_INP_REG 0x84
+#define MPFS_OUTP_REG 0x88
+
+struct mpfs_gpio_chip {
+ void __iomem *base;
+ struct clk *clk;
+ raw_spinlock_t lock;
+ struct gpio_chip gc;
+ unsigned int irq_number[NUM_GPIO];
+};
+
+static void mpfs_gpio_assign_bit(void __iomem *addr, unsigned int bit_offset, bool value)
+{
+ unsigned long reg = readl(addr);
+
+ __assign_bit(bit_offset, &reg, value);
+ writel(reg, addr);
+}
+
+static int mpfs_gpio_direction_input(struct gpio_chip *gc, unsigned int gpio_index)
+{
+ struct mpfs_gpio_chip *mpfs_gpio = gpiochip_get_data(gc);
+ u32 gpio_cfg;
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&mpfs_gpio->lock, flags);
+
+ gpio_cfg = readl(mpfs_gpio->base + MPFS_GPIO_CTRL(gpio_index));
+ gpio_cfg |= MPFS_GPIO_EN_IN;
+ gpio_cfg &= ~(MPFS_GPIO_EN_OUT | MPFS_GPIO_EN_OUT_BUF);
+ writel(gpio_cfg, mpfs_gpio->base + MPFS_GPIO_CTRL(gpio_index));
+
+ raw_spin_unlock_irqrestore(&mpfs_gpio->lock, flags);
+
+ return 0;
+}
+
+static int mpfs_gpio_direction_output(struct gpio_chip *gc, unsigned int gpio_index, int value)
+{
+ struct mpfs_gpio_chip *mpfs_gpio = gpiochip_get_data(gc);
+ u32 gpio_cfg;
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&mpfs_gpio->lock, flags);
+
+ gpio_cfg = readl(mpfs_gpio->base + MPFS_GPIO_CTRL(gpio_index));
+ gpio_cfg |= MPFS_GPIO_EN_OUT | MPFS_GPIO_EN_OUT_BUF;
+ gpio_cfg &= ~MPFS_GPIO_EN_IN;
+ writel(gpio_cfg, mpfs_gpio->base + MPFS_GPIO_CTRL(gpio_index));
+
+ mpfs_gpio_assign_bit(mpfs_gpio->base + MPFS_OUTP_REG, gpio_index, value);
+
+ raw_spin_unlock_irqrestore(&mpfs_gpio->lock, flags);
+
+ return 0;
+}
+
+static int mpfs_gpio_get_direction(struct gpio_chip *gc,
+ unsigned int gpio_index)
+{
+ struct mpfs_gpio_chip *mpfs_gpio = gpiochip_get_data(gc);
+ u32 gpio_cfg;
+
+ gpio_cfg = readl(mpfs_gpio->base + MPFS_GPIO_CTRL(gpio_index));
+ if (gpio_cfg & MPFS_GPIO_EN_IN)
+ return GPIO_LINE_DIRECTION_IN;
+
+ return GPIO_LINE_DIRECTION_OUT;
+}
+
+static int mpfs_gpio_get(struct gpio_chip *gc,
+ unsigned int gpio_index)
+{
+ struct mpfs_gpio_chip *mpfs_gpio = gpiochip_get_data(gc);
+
+ return !!(readl(mpfs_gpio->base + MPFS_INP_REG) & BIT(gpio_index));
+}
+
+static void mpfs_gpio_set(struct gpio_chip *gc, unsigned int gpio_index, int value)
+{
+ struct mpfs_gpio_chip *mpfs_gpio = gpiochip_get_data(gc);
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&mpfs_gpio->lock, flags);
+
+ mpfs_gpio_assign_bit(mpfs_gpio->base + MPFS_OUTP_REG,
+ gpio_index, value);
+
+ raw_spin_unlock_irqrestore(&mpfs_gpio->lock, flags);
+}
+
+static int mpfs_gpio_irq_set_type(struct irq_data *data, unsigned int type)
+{
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
+ struct mpfs_gpio_chip *mpfs_gpio = gpiochip_get_data(gc);
+ int gpio_index = irqd_to_hwirq(data);
+ u32 interrupt_type;
+ u32 gpio_cfg;
+ unsigned long flags;
+
+ switch (type) {
+ case IRQ_TYPE_EDGE_BOTH:
+ interrupt_type = MPFS_GPIO_TYPE_INT_EDGE_BOTH;
+ break;
+ case IRQ_TYPE_EDGE_FALLING:
+ interrupt_type = MPFS_GPIO_TYPE_INT_EDGE_NEG;
+ break;
+ case IRQ_TYPE_EDGE_RISING:
+ interrupt_type = MPFS_GPIO_TYPE_INT_EDGE_POS;
+ break;
+ case IRQ_TYPE_LEVEL_HIGH:
+ interrupt_type = MPFS_GPIO_TYPE_INT_LEVEL_HIGH;
+ break;
+ case IRQ_TYPE_LEVEL_LOW:
+ interrupt_type = MPFS_GPIO_TYPE_INT_LEVEL_LOW;
+ break;
+ }
+
+ raw_spin_lock_irqsave(&mpfs_gpio->lock, flags);
+
+ gpio_cfg = readl(mpfs_gpio->base + MPFS_GPIO_CTRL(gpio_index));
+ gpio_cfg &= ~MPFS_GPIO_TYPE_INT_MASK;
+ gpio_cfg |= interrupt_type;
+ writel(gpio_cfg, mpfs_gpio->base + MPFS_GPIO_CTRL(gpio_index));
+
+ raw_spin_unlock_irqrestore(&mpfs_gpio->lock, flags);
+
+ return 0;
+}
+
+static void mpfs_gpio_irq_enable(struct irq_data *data)
+{
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
+ struct mpfs_gpio_chip *mpfs_gpio = gpiochip_get_data(gc);
+ irq_hw_number_t hwirq = irqd_to_hwirq(data);
+ int gpio_index = hwirq % NUM_GPIO;
+
+ gpiochip_enable_irq(gc, hwirq);
+ irq_chip_enable_parent(data);
+
+ mpfs_gpio_direction_input(gc, gpio_index);
+ mpfs_gpio_assign_bit(mpfs_gpio->base + MPFS_IRQ_REG, gpio_index, 1);
+ mpfs_gpio_assign_bit(mpfs_gpio->base + MPFS_GPIO_CTRL(gpio_index),
+ MPFS_GPIO_EN_INT, 1);
+}
+
+static void mpfs_gpio_irq_disable(struct irq_data *data)
+{
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
+ struct mpfs_gpio_chip *mpfs_gpio = gpiochip_get_data(gc);
+ irq_hw_number_t hwirq = irqd_to_hwirq(data);
+ int gpio_index = hwirq % NUM_GPIO;
+
+ mpfs_gpio_assign_bit(mpfs_gpio->base + MPFS_IRQ_REG, gpio_index, 1);
+ mpfs_gpio_assign_bit(mpfs_gpio->base + MPFS_GPIO_CTRL(gpio_index),
+ MPFS_GPIO_EN_INT, 0);
+
+ irq_chip_disable_parent(data);
+ gpiochip_disable_irq(gc, hwirq);
+}
+
+static void mpfs_gpio_irq_eoi(struct irq_data *data)
+{
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
+ struct mpfs_gpio_chip *mpfs_gpio = gpiochip_get_data(gc);
+ int offset = irqd_to_hwirq(data) % NUM_GPIO;
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&mpfs_gpio->lock, flags);
+ /* Clear pending interrupt */
+ mpfs_gpio_assign_bit(mpfs_gpio->base + MPFS_IRQ_REG, offset, 1);
+ raw_spin_unlock_irqrestore(&mpfs_gpio->lock, flags);
+
+ irq_chip_eoi_parent(data);
+}
+
+static int mpfs_gpio_irq_set_affinity(struct irq_data *data,
+ const struct cpumask *dest,
+ bool force)
+{
+ if (data->parent_data)
+ return irq_chip_set_affinity_parent(data, dest, force);
+
+ return -EINVAL;
+}
+
+static const struct irq_chip mpfs_gpio_irqchip = {
+ .name = "mpfs",
+ .irq_set_type = mpfs_gpio_irq_set_type,
+ .irq_mask = irq_chip_mask_parent,
+ .irq_unmask = irq_chip_unmask_parent,
+ .irq_enable = mpfs_gpio_irq_enable,
+ .irq_disable = mpfs_gpio_irq_disable,
+ .irq_eoi = mpfs_gpio_irq_eoi,
+ .irq_set_affinity = mpfs_gpio_irq_set_affinity,
+ .flags = IRQCHIP_IMMUTABLE,
+ GPIOCHIP_IRQ_RESOURCE_HELPERS,
+};
+
+static int mpfs_gpio_child_to_parent_hwirq(struct gpio_chip *gc,
+ unsigned int child,
+ unsigned int child_type,
+ unsigned int *parent,
+ unsigned int *parent_type)
+{
+ struct mpfs_gpio_chip *mpfs_gpio = gpiochip_get_data(gc);
+ struct irq_data *d = irq_get_irq_data(mpfs_gpio->irq_number[child]);
+ *parent_type = IRQ_TYPE_NONE;
+ *parent = irqd_to_hwirq(d);
+
+ return 0;
+}
+
+static int mpfs_gpio_probe(struct platform_device *pdev)
+{
+ struct clk *clk;
+ struct device *dev = &pdev->dev;
+ struct device_node *node = pdev->dev.of_node;
+ struct device_node *irq_parent;
+ struct gpio_irq_chip *girq;
+ struct irq_domain *parent;
+ struct mpfs_gpio_chip *mpfs_gpio;
+ int i, ret, ngpio;
+
+ mpfs_gpio = devm_kzalloc(dev, sizeof(*mpfs_gpio), GFP_KERNEL);
+ if (!mpfs_gpio)
+ return -ENOMEM;
+
+ mpfs_gpio->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(mpfs_gpio->base))
+ return dev_err_probe(dev, PTR_ERR(mpfs_gpio->clk), "input clock not found.\n");
+
+ clk = devm_clk_get(dev, NULL);
+ if (IS_ERR(clk))
+ return dev_err_probe(dev, PTR_ERR(clk), "devm_clk_get failed\n");
+
+ ret = clk_prepare_enable(clk);
+ if (ret)
+ return dev_err_probe(dev, ret, "failed to enable clock\n");
+
+ mpfs_gpio->clk = clk;
+
+ ngpio = of_irq_count(node);
+ if (ngpio > NUM_GPIO) {
+ ret = -ENXIO;
+ goto cleanup_clock;
+ }
+
+ irq_parent = of_irq_find_parent(node);
+ if (!irq_parent) {
+ ret = -ENODEV;
+ goto cleanup_clock;
+ }
+ parent = irq_find_host(irq_parent);
+ if (!parent) {
+ ret = -ENODEV;
+ goto cleanup_clock;
+ }
+
+ /* Get the interrupt numbers. */
+ /* Clear/Disable All interrupts before enabling parent interrupts. */
+ for (i = 0; i < ngpio; i++) {
+ mpfs_gpio->irq_number[i] = platform_get_irq(pdev, i);
+ mpfs_gpio_assign_bit(mpfs_gpio->base + MPFS_IRQ_REG, i, 1);
+ mpfs_gpio_assign_bit(mpfs_gpio->base + MPFS_GPIO_CTRL(i),
+ MPFS_GPIO_EN_INT, 0);
+ }
+
+ raw_spin_lock_init(&mpfs_gpio->lock);
+
+ mpfs_gpio->gc.direction_input = mpfs_gpio_direction_input;
+ mpfs_gpio->gc.direction_output = mpfs_gpio_direction_output;
+ mpfs_gpio->gc.get_direction = mpfs_gpio_get_direction;
+ mpfs_gpio->gc.get = mpfs_gpio_get;
+ mpfs_gpio->gc.set = mpfs_gpio_set;
+ mpfs_gpio->gc.base = -1;
+ mpfs_gpio->gc.ngpio = ngpio;
+ mpfs_gpio->gc.label = dev_name(dev);
+ mpfs_gpio->gc.parent = dev;
+ mpfs_gpio->gc.owner = THIS_MODULE;
+
+ girq = &mpfs_gpio->gc.irq;
+ gpio_irq_chip_set_chip(girq, &mpfs_gpio_irqchip);
+ girq->fwnode = of_node_to_fwnode(node);
+ girq->parent_domain = parent;
+ girq->child_to_parent_hwirq = mpfs_gpio_child_to_parent_hwirq;
+ girq->handler = handle_bad_irq;
+ girq->default_type = IRQ_TYPE_NONE;
+
+ ret = devm_gpiochip_add_data(dev, &mpfs_gpio->gc, mpfs_gpio);
+ if (ret)
+ goto cleanup_clock;
+
+ platform_set_drvdata(pdev, mpfs_gpio);
+
+ return 0;
+
+cleanup_clock:
+ clk_disable_unprepare(mpfs_gpio->clk);
+ return ret;
+}
+
+static int mpfs_gpio_remove(struct platform_device *pdev)
+{
+ struct mpfs_gpio_chip *mpfs_gpio = platform_get_drvdata(pdev);
+
+ clk_disable_unprepare(mpfs_gpio->clk);
+ return 0;
+}
+
+static const struct of_device_id mpfs_of_ids[] = {
+ { .compatible = "microchip,mpfs-gpio", },
+ { /* end of list */ }
+};
+
+static struct platform_driver mpfs_gpio_driver = {
+ .probe = mpfs_gpio_probe,
+ .driver = {
+ .name = "microchip,mpfs-gpio",
+ .of_match_table = mpfs_of_ids,
+ },
+ .remove = mpfs_gpio_remove,
+};
+builtin_platform_driver(mpfs_gpio_driver);
--
2.25.1