[PATCH v2 2/2] gpio: Add GPIO driver for Spreadtrum SC9860 platform

From: Baolin Wang
Date: Wed Jan 31 2018 - 22:06:05 EST


The Spreadtrum SC9860 platform GPIO controller contains 16 groups and
each group contains 16 GPIOs. Each GPIO can set input/output and has
the interrupt capability.

Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxx>
Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
---
Changes since v1:
- Change 'bool' to 'tristate'.
- Add reviewed tag from Andy.
---
drivers/gpio/Kconfig | 7 ++
drivers/gpio/Makefile | 1 +
drivers/gpio/gpio-sprd.c | 291 ++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 299 insertions(+)
create mode 100644 drivers/gpio/gpio-sprd.c

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index d6a8e85..2ed1a88 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -404,6 +404,13 @@ config GPIO_SPEAR_SPICS
help
Say yes here to support ST SPEAr SPI Chip Select as GPIO device

+config GPIO_SPRD
+ tristate "Spreadtrum GPIO support"
+ depends on ARCH_SPRD || COMPILE_TEST
+ select GPIOLIB_IRQCHIP
+ help
+ Say yes here to support Spreadtrum GPIO device.
+
config GPIO_STA2X11
bool "STA2x11/ConneXt GPIO support"
depends on MFD_STA2X11
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 4bc24fe..5b633a0 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -108,6 +108,7 @@ obj-$(CONFIG_GPIO_SCH) += gpio-sch.o
obj-$(CONFIG_GPIO_SCH311X) += gpio-sch311x.o
obj-$(CONFIG_GPIO_SODAVILLE) += gpio-sodaville.o
obj-$(CONFIG_GPIO_SPEAR_SPICS) += gpio-spear-spics.o
+obj-$(CONFIG_GPIO_SPRD) += gpio-sprd.o
obj-$(CONFIG_GPIO_STA2X11) += gpio-sta2x11.o
obj-$(CONFIG_GPIO_STMPE) += gpio-stmpe.o
obj-$(CONFIG_GPIO_STP_XWAY) += gpio-stp-xway.o
diff --git a/drivers/gpio/gpio-sprd.c b/drivers/gpio/gpio-sprd.c
new file mode 100644
index 0000000..9dfea6c
--- /dev/null
+++ b/drivers/gpio/gpio-sprd.c
@@ -0,0 +1,291 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2018 Spreadtrum Communications Inc.
+ * Copyright (c) 2018 Linaro Ltd.
+ */
+
+#include <linux/bitops.h>
+#include <linux/gpio/driver.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/spinlock.h>
+
+/* GPIO registers definition */
+#define SPRD_GPIO_DATA 0x0
+#define SPRD_GPIO_DMSK 0x4
+#define SPRD_GPIO_DIR 0x8
+#define SPRD_GPIO_IS 0xc
+#define SPRD_GPIO_IBE 0x10
+#define SPRD_GPIO_IEV 0x14
+#define SPRD_GPIO_IE 0x18
+#define SPRD_GPIO_RIS 0x1c
+#define SPRD_GPIO_MIS 0x20
+#define SPRD_GPIO_IC 0x24
+#define SPRD_GPIO_INEN 0x28
+
+/* We have 16 groups GPIOs and each group contain 16 GPIOs */
+#define SPRD_GPIO_GROUP_NR 16
+#define SPRD_GPIO_NR 256
+#define SPRD_GPIO_GROUP_SIZE 0x80
+#define SPRD_GPIO_GROUP_MASK GENMASK(15, 0)
+#define SPRD_GPIO_BIT(x) ((x) & (SPRD_GPIO_GROUP_NR - 1))
+
+struct sprd_gpio {
+ struct gpio_chip chip;
+ void __iomem *base;
+ spinlock_t lock;
+ int irq;
+};
+
+static inline void __iomem *sprd_gpio_group_base(struct sprd_gpio *sprd_gpio,
+ unsigned int group)
+{
+ return sprd_gpio->base + SPRD_GPIO_GROUP_SIZE * group;
+}
+
+static void sprd_gpio_update(struct gpio_chip *chip, unsigned int offset,
+ unsigned int reg, unsigned int val)
+{
+ struct sprd_gpio *sprd_gpio = gpiochip_get_data(chip);
+ void __iomem *base = sprd_gpio_group_base(sprd_gpio,
+ offset / SPRD_GPIO_GROUP_NR);
+ u32 shift = SPRD_GPIO_BIT(offset);
+ unsigned long flags;
+ u32 orig, tmp;
+
+ spin_lock_irqsave(&sprd_gpio->lock, flags);
+ orig = readl_relaxed(base + reg);
+
+ tmp = (orig & ~BIT(shift)) | (val << shift);
+ writel_relaxed(tmp, base + reg);
+ spin_unlock_irqrestore(&sprd_gpio->lock, flags);
+}
+
+static int sprd_gpio_read(struct gpio_chip *chip, unsigned int offset,
+ unsigned int reg)
+{
+ struct sprd_gpio *sprd_gpio = gpiochip_get_data(chip);
+ void __iomem *base = sprd_gpio_group_base(sprd_gpio,
+ offset / SPRD_GPIO_GROUP_NR);
+ u32 value = readl_relaxed(base + reg) & SPRD_GPIO_GROUP_MASK;
+ u32 shift = SPRD_GPIO_BIT(offset);
+
+ return !!(value & BIT(shift));
+}
+
+static int sprd_gpio_request(struct gpio_chip *chip, unsigned int offset)
+{
+ sprd_gpio_update(chip, offset, SPRD_GPIO_DMSK, 1);
+ return 0;
+}
+
+static void sprd_gpio_free(struct gpio_chip *chip, unsigned int offset)
+{
+ sprd_gpio_update(chip, offset, SPRD_GPIO_DMSK, 0);
+}
+
+static int sprd_gpio_direction_input(struct gpio_chip *chip,
+ unsigned int offset)
+{
+ sprd_gpio_update(chip, offset, SPRD_GPIO_DIR, 0);
+ sprd_gpio_update(chip, offset, SPRD_GPIO_INEN, 1);
+ return 0;
+}
+
+static int sprd_gpio_direction_output(struct gpio_chip *chip,
+ unsigned int offset, int value)
+{
+ sprd_gpio_update(chip, offset, SPRD_GPIO_DIR, 1);
+ sprd_gpio_update(chip, offset, SPRD_GPIO_INEN, 0);
+ sprd_gpio_update(chip, offset, SPRD_GPIO_DATA, value);
+ return 0;
+}
+
+static int sprd_gpio_get(struct gpio_chip *chip, unsigned int offset)
+{
+ return sprd_gpio_read(chip, offset, SPRD_GPIO_DATA);
+}
+
+static void sprd_gpio_set(struct gpio_chip *chip, unsigned int offset,
+ int value)
+{
+ sprd_gpio_update(chip, offset, SPRD_GPIO_DATA, value);
+}
+
+static void sprd_gpio_irq_mask(struct irq_data *data)
+{
+ struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
+ u32 offset = irqd_to_hwirq(data);
+
+ sprd_gpio_update(chip, offset, SPRD_GPIO_IE, 0);
+}
+
+static void sprd_gpio_irq_ack(struct irq_data *data)
+{
+ struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
+ u32 offset = irqd_to_hwirq(data);
+
+ sprd_gpio_update(chip, offset, SPRD_GPIO_IC, 1);
+}
+
+static void sprd_gpio_irq_unmask(struct irq_data *data)
+{
+ struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
+ u32 offset = irqd_to_hwirq(data);
+
+ sprd_gpio_update(chip, offset, SPRD_GPIO_IE, 1);
+}
+
+static int sprd_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);
+
+ switch (flow_type) {
+ case IRQ_TYPE_EDGE_RISING:
+ sprd_gpio_update(chip, offset, SPRD_GPIO_IS, 0);
+ sprd_gpio_update(chip, offset, SPRD_GPIO_IBE, 0);
+ sprd_gpio_update(chip, offset, SPRD_GPIO_IEV, 1);
+ irq_set_handler_locked(data, handle_edge_irq);
+ break;
+ case IRQ_TYPE_EDGE_FALLING:
+ sprd_gpio_update(chip, offset, SPRD_GPIO_IS, 0);
+ sprd_gpio_update(chip, offset, SPRD_GPIO_IBE, 0);
+ sprd_gpio_update(chip, offset, SPRD_GPIO_IEV, 0);
+ irq_set_handler_locked(data, handle_edge_irq);
+ break;
+ case IRQ_TYPE_EDGE_BOTH:
+ sprd_gpio_update(chip, offset, SPRD_GPIO_IS, 0);
+ sprd_gpio_update(chip, offset, SPRD_GPIO_IBE, 1);
+ irq_set_handler_locked(data, handle_edge_irq);
+ break;
+ case IRQ_TYPE_LEVEL_HIGH:
+ sprd_gpio_update(chip, offset, SPRD_GPIO_IS, 1);
+ sprd_gpio_update(chip, offset, SPRD_GPIO_IBE, 0);
+ sprd_gpio_update(chip, offset, SPRD_GPIO_IEV, 1);
+ irq_set_handler_locked(data, handle_level_irq);
+ break;
+ case IRQ_TYPE_LEVEL_LOW:
+ sprd_gpio_update(chip, offset, SPRD_GPIO_IS, 1);
+ sprd_gpio_update(chip, offset, SPRD_GPIO_IBE, 0);
+ sprd_gpio_update(chip, offset, SPRD_GPIO_IEV, 0);
+ irq_set_handler_locked(data, handle_level_irq);
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static void sprd_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 sprd_gpio *sprd_gpio = gpiochip_get_data(chip);
+ u32 group, n, girq;
+
+ chained_irq_enter(ic, desc);
+
+ for (group = 0; group * SPRD_GPIO_GROUP_NR < chip->ngpio; group++) {
+ void __iomem *base = sprd_gpio_group_base(sprd_gpio, group);
+ unsigned long reg = readl_relaxed(base + SPRD_GPIO_MIS) &
+ SPRD_GPIO_GROUP_MASK;
+
+ for_each_set_bit(n, &reg, SPRD_GPIO_GROUP_NR) {
+ girq = irq_find_mapping(chip->irq.domain,
+ group * SPRD_GPIO_GROUP_NR + n);
+
+ generic_handle_irq(girq);
+ }
+
+ }
+ chained_irq_exit(ic, desc);
+}
+
+static struct irq_chip sprd_gpio_irqchip = {
+ .name = "sprd-gpio",
+ .irq_ack = sprd_gpio_irq_ack,
+ .irq_mask = sprd_gpio_irq_mask,
+ .irq_unmask = sprd_gpio_irq_unmask,
+ .irq_set_type = sprd_gpio_irq_set_type,
+ .flags = IRQCHIP_SKIP_SET_WAKE,
+};
+
+static int sprd_gpio_probe(struct platform_device *pdev)
+{
+ struct gpio_irq_chip *irq;
+ struct sprd_gpio *sprd_gpio;
+ struct resource *res;
+ int ret;
+
+ sprd_gpio = devm_kzalloc(&pdev->dev, sizeof(*sprd_gpio), GFP_KERNEL);
+ if (!sprd_gpio)
+ return -ENOMEM;
+
+ sprd_gpio->irq = platform_get_irq(pdev, 0);
+ if (sprd_gpio->irq < 0) {
+ dev_err(&pdev->dev, "Failed to get GPIO interrupt.\n");
+ return sprd_gpio->irq;
+ }
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ sprd_gpio->base = devm_ioremap_nocache(&pdev->dev, res->start,
+ resource_size(res));
+ if (!sprd_gpio->base)
+ return -ENOMEM;
+
+ spin_lock_init(&sprd_gpio->lock);
+
+ sprd_gpio->chip.label = dev_name(&pdev->dev);
+ sprd_gpio->chip.ngpio = SPRD_GPIO_NR;
+ sprd_gpio->chip.base = -1;
+ sprd_gpio->chip.parent = &pdev->dev;
+ sprd_gpio->chip.of_node = pdev->dev.of_node;
+ sprd_gpio->chip.request = sprd_gpio_request;
+ sprd_gpio->chip.free = sprd_gpio_free;
+ sprd_gpio->chip.get = sprd_gpio_get;
+ sprd_gpio->chip.set = sprd_gpio_set;
+ sprd_gpio->chip.direction_input = sprd_gpio_direction_input;
+ sprd_gpio->chip.direction_output = sprd_gpio_direction_output;
+
+ irq = &sprd_gpio->chip.irq;
+ irq->chip = &sprd_gpio_irqchip;
+ irq->handler = handle_simple_irq;
+ irq->default_type = IRQ_TYPE_NONE;
+ irq->parent_handler = sprd_gpio_irq_handler;
+ irq->parent_handler_data = sprd_gpio;
+ irq->num_parents = 1;
+ irq->parents = &sprd_gpio->irq;
+
+ ret = devm_gpiochip_add_data(&pdev->dev, &sprd_gpio->chip, sprd_gpio);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Could not register gpiochip %d\n", ret);
+ return ret;
+ }
+
+ platform_set_drvdata(pdev, sprd_gpio);
+ return 0;
+}
+
+static const struct of_device_id sprd_gpio_of_match[] = {
+ { .compatible = "sprd,sc9860-gpio", },
+ { /* end of list */ },
+};
+MODULE_DEVICE_TABLE(of, sprd_gpio_of_match);
+
+static struct platform_driver sprd_gpio_driver = {
+ .probe = sprd_gpio_probe,
+ .driver = {
+ .name = "sprd-gpio",
+ .of_match_table = sprd_gpio_of_match,
+ },
+};
+
+module_platform_driver_probe(sprd_gpio_driver, sprd_gpio_probe);
+
+MODULE_DESCRIPTION("Spreadtrum GPIO driver");
+MODULE_LICENSE("GPL v2");
--
1.7.9.5