* [PATCH v3 1/2] dt-bindings: gpio: Add bindings for Cadence GPIO
2018-12-18 16:10 [PATCH v3 0/2] gpio: Add a driver for Cadence GPIO controller Jan Kotas
@ 2018-12-18 16:10 ` Jan Kotas
2018-12-21 10:40 ` Linus Walleij
2018-12-18 16:10 ` [PATCH v3 2/2] gpio: Add Cadence GPIO driver Jan Kotas
1 sibling, 1 reply; 5+ messages in thread
From: Jan Kotas @ 2018-12-18 16:10 UTC (permalink / raw)
To: linus.walleij, bgolaszewski, robh+dt, mark.rutland
Cc: linux-gpio, devicetree, linux-kernel, Jan Kotas
This patch adds a DT binding documentation for
Cadence GPIO controller.
Signed-off-by: Jan Kotas <jank@cadence.com>
---
.../devicetree/bindings/gpio/cdns,gpio.txt | 44 ++++++++++++++++++++++
1 file changed, 44 insertions(+)
create mode 100644 Documentation/devicetree/bindings/gpio/cdns,gpio.txt
diff --git a/Documentation/devicetree/bindings/gpio/cdns,gpio.txt b/Documentation/devicetree/bindings/gpio/cdns,gpio.txt
new file mode 100644
index 000000000..c87a47827
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/cdns,gpio.txt
@@ -0,0 +1,44 @@
+Cadence GPIO controller bindings
+
+Required properties:
+- compatible: should be "cdns,gpio-r1p02".
+- reg: the register base address and size.
+- #gpio-cells: should be 2.
+ * first cell is the GPIO number.
+ * second cell specifies the GPIO flags, as defined in
+ <dt-bindings/gpio/gpio.h>. Only the GPIO_ACTIVE_HIGH
+ and GPIO_ACTIVE_LOW flags are supported.
+- gpio-controller: marks the device as a GPIO controller.
+- clocks: should contain one entry referencing the peripheral clock driving
+ the GPIO controller.
+
+Optional properties:
+- ngpios: integer number of gpio lines supported by this controller, up to 32.
+- interrupt-parent: phandle of the parent interrupt controller.
+- interrupts: interrupt specifier for the controllers interrupt.
+- interrupt-controller: marks the device as an interrupt controller. When
+ defined, interrupts, interrupt-parent and #interrupt-cells
+ are required.
+- interrupt-cells: should be 2.
+ * first cell is the GPIO number you want to use as an IRQ source.
+ * second cell specifies the IRQ type, as defined in
+ <dt-bindings/interrupt-controller/irq.h>.
+ Currently only level sensitive IRQs are supported.
+
+
+Example:
+ gpio0: gpio-controller@fd060000 {
+ compatible = "cdns,gpio-r1p02";
+ reg =<0xfd060000 0x1000>;
+
+ clocks = <&gpio_clk>;
+
+ interrupt-parent = <&gic>;
+ interrupts = <0 5 IRQ_TYPE_LEVEL_HIGH>;
+
+ gpio-controller;
+ #gpio-cells = <2>;
+
+ interrupt-controller;
+ #interrupt-cells = <2>;
+ };
--
2.15.0
^ permalink raw reply related [flat|nested] 5+ messages in thread* [PATCH v3 2/2] gpio: Add Cadence GPIO driver
2018-12-18 16:10 [PATCH v3 0/2] gpio: Add a driver for Cadence GPIO controller Jan Kotas
2018-12-18 16:10 ` [PATCH v3 1/2] dt-bindings: gpio: Add bindings for Cadence GPIO Jan Kotas
@ 2018-12-18 16:10 ` Jan Kotas
2018-12-21 10:41 ` Linus Walleij
1 sibling, 1 reply; 5+ messages in thread
From: Jan Kotas @ 2018-12-18 16:10 UTC (permalink / raw)
To: linus.walleij, bgolaszewski, robh+dt, mark.rutland
Cc: linux-gpio, devicetree, linux-kernel, Jan Kotas
This patch adds a driver for Cadence GPIO controller.
It can be enabled with GPIO_CADENCE Kconfig option.
It uses generic GPIO infrastructure and works
as an interrupt controller.
At the moment it only supports level sensitive irqs.
Signed-off-by: Jan Kotas <jank@cadence.com>
---
drivers/gpio/Kconfig | 8 ++
drivers/gpio/Makefile | 1 +
drivers/gpio/gpio-cadence.c | 291 ++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 300 insertions(+)
create mode 100644 drivers/gpio/gpio-cadence.c
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 833a1b51c..8259f8f25 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -160,6 +160,14 @@ config GPIO_BRCMSTB
help
Say yes here to enable GPIO support for Broadcom STB (BCM7XXX) SoCs.
+config GPIO_CADENCE
+ tristate "Cadence GPIO support"
+ depends on OF_GPIO
+ select GPIO_GENERIC
+ select GPIOLIB_IRQCHIP
+ help
+ Say yes here to enable support for Cadence GPIO controller.
+
config GPIO_CLPS711X
tristate "CLPS711X GPIO support"
depends on ARCH_CLPS711X || COMPILE_TEST
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 671c4477c..5fce8634a 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -37,6 +37,7 @@ obj-$(CONFIG_GPIO_BCM_KONA) += gpio-bcm-kona.o
obj-$(CONFIG_GPIO_BD9571MWV) += gpio-bd9571mwv.o
obj-$(CONFIG_GPIO_BRCMSTB) += gpio-brcmstb.o
obj-$(CONFIG_GPIO_BT8XX) += gpio-bt8xx.o
+obj-$(CONFIG_GPIO_CADENCE) += gpio-cadence.o
obj-$(CONFIG_GPIO_CLPS711X) += gpio-clps711x.o
obj-$(CONFIG_GPIO_CS5535) += gpio-cs5535.o
obj-$(CONFIG_GPIO_CRYSTAL_COVE) += gpio-crystalcove.o
diff --git a/drivers/gpio/gpio-cadence.c b/drivers/gpio/gpio-cadence.c
new file mode 100644
index 000000000..aec8d5df9
--- /dev/null
+++ b/drivers/gpio/gpio-cadence.c
@@ -0,0 +1,291 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/*
+ * Copyright 2017-2018 Cadence
+ *
+ * Authors:
+ * Jan Kotas <jank@cadence.com>
+ * Boris Brezillon <boris.brezillon@free-electrons.com>
+ */
+
+#include <linux/gpio/driver.h>
+#include <linux/clk.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/spinlock.h>
+
+#define CDNS_GPIO_BYPASS_MODE 0x00
+#define CDNS_GPIO_DIRECTION_MODE 0x04
+#define CDNS_GPIO_OUTPUT_EN 0x08
+#define CDNS_GPIO_OUTPUT_VALUE 0x0c
+#define CDNS_GPIO_INPUT_VALUE 0x10
+#define CDNS_GPIO_IRQ_MASK 0x14
+#define CDNS_GPIO_IRQ_EN 0x18
+#define CDNS_GPIO_IRQ_DIS 0x1c
+#define CDNS_GPIO_IRQ_STATUS 0x20
+#define CDNS_GPIO_IRQ_TYPE 0x24
+#define CDNS_GPIO_IRQ_VALUE 0x28
+#define CDNS_GPIO_IRQ_ANY_EDGE 0x2c
+
+struct cdns_gpio_chip {
+ struct gpio_chip gc;
+ struct clk *pclk;
+ void __iomem *regs;
+ u32 bypass_orig;
+};
+
+static int cdns_gpio_request(struct gpio_chip *chip, unsigned int offset)
+{
+ struct cdns_gpio_chip *cgpio = gpiochip_get_data(chip);
+ unsigned long flags;
+
+ spin_lock_irqsave(&chip->bgpio_lock, flags);
+
+ iowrite32(ioread32(cgpio->regs + CDNS_GPIO_BYPASS_MODE) & ~BIT(offset),
+ cgpio->regs + CDNS_GPIO_BYPASS_MODE);
+
+ spin_unlock_irqrestore(&chip->bgpio_lock, flags);
+ return 0;
+}
+
+static void cdns_gpio_free(struct gpio_chip *chip, unsigned int offset)
+{
+ struct cdns_gpio_chip *cgpio = gpiochip_get_data(chip);
+ unsigned long flags;
+
+ spin_lock_irqsave(&chip->bgpio_lock, flags);
+
+ iowrite32(ioread32(cgpio->regs + CDNS_GPIO_BYPASS_MODE) |
+ (BIT(offset) & cgpio->bypass_orig),
+ cgpio->regs + CDNS_GPIO_BYPASS_MODE);
+
+ spin_unlock_irqrestore(&chip->bgpio_lock, flags);
+}
+
+static void cdns_gpio_irq_mask(struct irq_data *d)
+{
+ struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
+ struct cdns_gpio_chip *cgpio = gpiochip_get_data(chip);
+
+ iowrite32(BIT(d->hwirq), cgpio->regs + CDNS_GPIO_IRQ_DIS);
+}
+
+static void cdns_gpio_irq_unmask(struct irq_data *d)
+{
+ struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
+ struct cdns_gpio_chip *cgpio = gpiochip_get_data(chip);
+
+ iowrite32(BIT(d->hwirq), cgpio->regs + CDNS_GPIO_IRQ_EN);
+}
+
+static int cdns_gpio_irq_set_type(struct irq_data *d, unsigned int type)
+{
+ struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
+ struct cdns_gpio_chip *cgpio = gpiochip_get_data(chip);
+ unsigned long flags;
+ u32 int_value;
+ u32 int_type;
+ u32 mask = BIT(d->hwirq);
+ int ret = 0;
+
+ spin_lock_irqsave(&chip->bgpio_lock, flags);
+
+ int_value = ioread32(cgpio->regs + CDNS_GPIO_IRQ_VALUE) & ~mask;
+ int_type = ioread32(cgpio->regs + CDNS_GPIO_IRQ_TYPE) & ~mask;
+
+ /*
+ * The GPIO controller doesn't have an ACK register.
+ * All interrupt statuses are cleared on a status register read.
+ * Don't support edge interrupts for now.
+ */
+
+ if (type == IRQ_TYPE_LEVEL_HIGH) {
+ int_type |= mask;
+ int_value |= mask;
+ } else if (type == IRQ_TYPE_LEVEL_LOW) {
+ int_type |= mask;
+ } else {
+ ret = -EINVAL;
+ goto err_irq_type;
+ }
+
+ iowrite32(int_value, cgpio->regs + CDNS_GPIO_IRQ_VALUE);
+ iowrite32(int_type, cgpio->regs + CDNS_GPIO_IRQ_TYPE);
+
+err_irq_type:
+ spin_unlock_irqrestore(&chip->bgpio_lock, flags);
+ return ret;
+}
+
+static void cdns_gpio_irq_handler(struct irq_desc *desc)
+{
+ struct gpio_chip *chip = irq_desc_get_handler_data(desc);
+ struct cdns_gpio_chip *cgpio = gpiochip_get_data(chip);
+ struct irq_chip *irqchip = irq_desc_get_chip(desc);
+ unsigned long status;
+ int hwirq;
+
+ chained_irq_enter(irqchip, desc);
+
+ status = ioread32(cgpio->regs + CDNS_GPIO_IRQ_STATUS) &
+ ~ioread32(cgpio->regs + CDNS_GPIO_IRQ_MASK);
+
+ for_each_set_bit(hwirq, &status, chip->ngpio)
+ generic_handle_irq(irq_find_mapping(chip->irq.domain, hwirq));
+
+ chained_irq_exit(irqchip, desc);
+}
+
+static struct irq_chip cdns_gpio_irqchip = {
+ .name = "cdns-gpio",
+ .irq_mask = cdns_gpio_irq_mask,
+ .irq_unmask = cdns_gpio_irq_unmask,
+ .irq_set_type = cdns_gpio_irq_set_type
+};
+
+static int cdns_gpio_probe(struct platform_device *pdev)
+{
+ struct cdns_gpio_chip *cgpio;
+ struct resource *res;
+ int ret, irq;
+ u32 dir_prev;
+ u32 num_gpios = 32;
+
+ cgpio = devm_kzalloc(&pdev->dev, sizeof(*cgpio), GFP_KERNEL);
+ if (!cgpio)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ cgpio->regs = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(cgpio->regs))
+ return PTR_ERR(cgpio->regs);
+
+ of_property_read_u32(pdev->dev.of_node, "ngpios", &num_gpios);
+
+ if (num_gpios > 32) {
+ dev_err(&pdev->dev, "ngpios must be less or equal 32\n");
+ return -EINVAL;
+ }
+
+ /*
+ * Set all pins as inputs by default, otherwise:
+ * gpiochip_lock_as_irq:
+ * tried to flag a GPIO set as output for IRQ
+ * Generic GPIO driver stores the direction value internally,
+ * so it needs to be changed before bgpio_init() is called.
+ */
+ dir_prev = ioread32(cgpio->regs + CDNS_GPIO_DIRECTION_MODE);
+ iowrite32(GENMASK(num_gpios - 1, 0),
+ cgpio->regs + CDNS_GPIO_DIRECTION_MODE);
+
+ ret = bgpio_init(&cgpio->gc, &pdev->dev, 4,
+ cgpio->regs + CDNS_GPIO_INPUT_VALUE,
+ cgpio->regs + CDNS_GPIO_OUTPUT_VALUE,
+ NULL,
+ NULL,
+ cgpio->regs + CDNS_GPIO_DIRECTION_MODE,
+ BGPIOF_READ_OUTPUT_REG_SET);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to register generic gpio, %d\n",
+ ret);
+ goto err_revert_dir;
+ }
+
+ cgpio->gc.label = dev_name(&pdev->dev);
+ cgpio->gc.ngpio = num_gpios;
+ cgpio->gc.parent = &pdev->dev;
+ cgpio->gc.base = -1;
+ cgpio->gc.owner = THIS_MODULE;
+ cgpio->gc.request = cdns_gpio_request;
+ cgpio->gc.free = cdns_gpio_free;
+
+ cgpio->pclk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(cgpio->pclk)) {
+ ret = PTR_ERR(cgpio->pclk);
+ dev_err(&pdev->dev,
+ "Failed to retrieve peripheral clock, %d\n", ret);
+ goto err_revert_dir;
+ }
+
+ ret = clk_prepare_enable(cgpio->pclk);
+ if (ret) {
+ dev_err(&pdev->dev,
+ "Failed to enable the peripheral clock, %d\n", ret);
+ goto err_revert_dir;
+ }
+
+ ret = devm_gpiochip_add_data(&pdev->dev, &cgpio->gc, cgpio);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
+ goto err_disable_clk;
+ }
+
+ /*
+ * irq_chip support
+ */
+ irq = platform_get_irq(pdev, 0);
+ if (irq >= 0) {
+ ret = gpiochip_irqchip_add(&cgpio->gc, &cdns_gpio_irqchip,
+ 0, handle_level_irq,
+ IRQ_TYPE_NONE);
+ if (ret) {
+ dev_err(&pdev->dev, "Could not add irqchip, %d\n",
+ ret);
+ goto err_disable_clk;
+ }
+ gpiochip_set_chained_irqchip(&cgpio->gc, &cdns_gpio_irqchip,
+ irq, cdns_gpio_irq_handler);
+ }
+
+ cgpio->bypass_orig = ioread32(cgpio->regs + CDNS_GPIO_BYPASS_MODE);
+
+ /*
+ * Enable gpio outputs, ignored for input direction
+ */
+ iowrite32(GENMASK(num_gpios - 1, 0),
+ cgpio->regs + CDNS_GPIO_OUTPUT_EN);
+ iowrite32(0, cgpio->regs + CDNS_GPIO_BYPASS_MODE);
+
+ platform_set_drvdata(pdev, cgpio);
+ return 0;
+
+err_disable_clk:
+ clk_disable_unprepare(cgpio->pclk);
+
+err_revert_dir:
+ iowrite32(dir_prev, cgpio->regs + CDNS_GPIO_DIRECTION_MODE);
+
+ return ret;
+}
+
+static int cdns_gpio_remove(struct platform_device *pdev)
+{
+ struct cdns_gpio_chip *cgpio = platform_get_drvdata(pdev);
+
+ iowrite32(cgpio->bypass_orig, cgpio->regs + CDNS_GPIO_BYPASS_MODE);
+ clk_disable_unprepare(cgpio->pclk);
+
+ return 0;
+}
+
+static const struct of_device_id cdns_of_ids[] = {
+ { .compatible = "cdns,gpio-r1p02" },
+ { /* sentinel */ },
+};
+
+static struct platform_driver cdns_gpio_driver = {
+ .driver = {
+ .name = "cdns-gpio",
+ .of_match_table = cdns_of_ids,
+ },
+ .probe = cdns_gpio_probe,
+ .remove = cdns_gpio_remove,
+};
+module_platform_driver(cdns_gpio_driver);
+
+MODULE_AUTHOR("Jan Kotas <jank@cadence.com>");
+MODULE_DESCRIPTION("Cadence GPIO driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:cdns-gpio");
--
2.15.0
^ permalink raw reply related [flat|nested] 5+ messages in thread