Re: [PATCH v12] gpio: add a driver for the Synopsys DesignWare APB GPIO block
From: delicious quinoa
Date: Wed Feb 26 2014 - 10:53:20 EST
On Tue, Feb 25, 2014 at 5:01 PM, Alan Tull <delicious.quinoa@xxxxxxxxx> wrote:
> From: Jamie Iles <jamie@xxxxxxxxxxxxx>
>
> The Synopsys DesignWare block is used in some ARM devices (picoxcell)
> and can be configured to provide multiple banks of GPIO pins.
>
> Signed-off-by: Jamie Iles <jamie@xxxxxxxxxxxxx>
> Signed-off-by: Alan Tull <atull@xxxxxxxxxx>
> Reviewed-by: Sebastian Hesselbarth <sebastian.hesselbarth@xxxxxxxxx>
>
> v12: - Add irq_startup/shutdown
> - do irq_create_mapping() in probe, irq_find_mapping() in to_irq()
> - Adjust mappings to show support for 1 gpio per port.
> - gpio-cells = <1>
> v11: - Use NULL when checking existence of 'interrupts' property
> - Bindings descriptions cleanup
> v10: - in documentation nr-gpio -> nr-gpios
> v9: - cleanup in dt bindings doc
> - use of_get_child_count()
> v8: - remove socfpga.dtsi changes
> - minor cleanup in devicetree documentation
> v7: - use irq_generic_chip
> - support one irq per gpio line or one irq for many
> - s/bank/port/ and other cleanup
> v6: - (atull) squash the set of patches
> - use linear irq domain
> - build fixes. Original driver was reviewed on v3.2.
> - Fix setting irq edge type for 'rising' and 'both'.
> - Support as a loadable module.
> - Use bgpio_chip's spinlock during register access.
> - Clean up register names to match spec
> - s/bank/port/ because register names use the word 'port'
> - s/nr-gpio/nr-gpios/
> - don't get/put the of_node
> - remove signoffs/acked-by's because of changes
> - other cleanup
> v5: - handle sparse bank population correctly
> v3: - depend on rather than select IRQ_DOMAIN
> - split IRQ support into a separate patch
> v2: - use Rob Herring's irqdomain in generic irq chip patches
> - use reg property to indicate bank index
> - support irqs on both edges based on LinusW's u300 driver
> ---
> .../devicetree/bindings/gpio/snps-dwapb-gpio.txt | 57 +++
> drivers/gpio/Kconfig | 9 +
> drivers/gpio/Makefile | 1 +
> drivers/gpio/gpio-dwapb.c | 438 ++++++++++++++++++++
> 4 files changed, 505 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/gpio/snps-dwapb-gpio.txt
> create mode 100644 drivers/gpio/gpio-dwapb.c
>
> diff --git a/Documentation/devicetree/bindings/gpio/snps-dwapb-gpio.txt b/Documentation/devicetree/bindings/gpio/snps-dwapb-gpio.txt
> new file mode 100644
> index 0000000..0934950
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/gpio/snps-dwapb-gpio.txt
> @@ -0,0 +1,57 @@
> +* Synopsys DesignWare APB GPIO controller
> +
> +Required properties:
> +- compatible : Should contain "snps,dw-apb-gpio"
> +- reg : Address and length of the register set for the device.
> +- #address-cells : should be 1 (for addressing port subnodes).
> +- #size-cells : should be 0 (port subnodes).
> +
> +The GPIO controller has a configurable number of ports, each of which are
> +represented as child nodes with the following properties:
> +
> +Required properties:
> +- compatible : "snps,dw-apb-gpio-port"
> +- gpio-controller : Marks the device node as a gpio controller.
> +- #gpio-cells : Should be 1. It is the pin number.
> +- reg : The integer port index of the port, a single cell.
> +
> +Optional properties:
> +- interrupt-controller : The first port may be configured to be an interrupt
> +controller.
> +- #interrupt-cells : Specifies the number of cells needed to encode an
> + interrupt. Shall be set to 2. The first cell defines the interrupt number,
> + the second encodes the triger flags encoded as described in
> + Documentation/devicetree/bindings/interrupts.txt
> +- interrupt-parent : The parent interrupt controller.
> +- interrupts : The interrupt to the parent controller raised when GPIOs
> + generate the interrupts.
> +- snps,nr-gpios : The number of pins in the port, a single cell.
> +
> +Example:
> +
> +gpio: gpio@20000 {
> + compatible = "snps,dw-apb-gpio";
> + reg = <0x20000 0x1000>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + porta: gpio-controller@0 {
> + compatible = "snps,dw-apb-gpio-port";
> + gpio-controller;
> + #gpio-cells = <1>;
> + snps,nr-gpios = <8>;
> + reg = <0>;
> + interrupt-controller;
> + #interrupt-cells = <2>;
> + interrupt-parent = <&vic1>;
> + interrupts = <0>;
> + };
> +
> + portb: gpio-controller@1 {
> + compatible = "snps,dw-apb-gpio-port";
> + gpio-controller;
> + #gpio-cells = <1>;
> + snps,nr-gpios = <8>;
> + reg = <1>;
> + };
> +};
Hi Rob,
Are these bindings acceptable?
Alan
> diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
> index 903f24d..9979017 100644
> --- a/drivers/gpio/Kconfig
> +++ b/drivers/gpio/Kconfig
> @@ -128,6 +128,15 @@ config GPIO_GENERIC_PLATFORM
> help
> Say yes here to support basic platform_device memory-mapped GPIO controllers.
>
> +config GPIO_DWAPB
> + tristate "Synopsys DesignWare APB GPIO driver"
> + select GPIO_GENERIC
> + select GENERIC_IRQ_CHIP
> + depends on OF_GPIO && IRQ_DOMAIN
> + help
> + Say Y or M here to build support for the Synopsys DesignWare APB
> + GPIO block.
> +
> config GPIO_IT8761E
> tristate "IT8761E GPIO support"
> depends on X86 # unconditional access to IO space.
> diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
> index 5d50179..2d09f04 100644
> --- a/drivers/gpio/Makefile
> +++ b/drivers/gpio/Makefile
> @@ -23,6 +23,7 @@ obj-$(CONFIG_GPIO_CS5535) += gpio-cs5535.o
> obj-$(CONFIG_GPIO_DA9052) += gpio-da9052.o
> obj-$(CONFIG_GPIO_DA9055) += gpio-da9055.o
> obj-$(CONFIG_GPIO_DAVINCI) += gpio-davinci.o
> +obj-$(CONFIG_GPIO_DWAPB) += gpio-dwapb.o
> obj-$(CONFIG_GPIO_EM) += gpio-em.o
> obj-$(CONFIG_GPIO_EP93XX) += gpio-ep93xx.o
> obj-$(CONFIG_GPIO_F7188X) += gpio-f7188x.o
> diff --git a/drivers/gpio/gpio-dwapb.c b/drivers/gpio/gpio-dwapb.c
> new file mode 100644
> index 0000000..2797fbb
> --- /dev/null
> +++ b/drivers/gpio/gpio-dwapb.c
> @@ -0,0 +1,438 @@
> +/*
> + * Copyright (c) 2011 Jamie Iles
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * All enquiries to support@xxxxxxxxxxxx
> + */
> +#include <linux/basic_mmio_gpio.h>
> +#include <linux/err.h>
> +#include <linux/init.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/ioport.h>
> +#include <linux/irq.h>
> +#include <linux/irqdomain.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/of_irq.h>
> +#include <linux/platform_device.h>
> +#include <linux/spinlock.h>
> +
> +#define GPIO_SWPORTA_DR 0x00
> +#define GPIO_SWPORTA_DDR 0x04
> +#define GPIO_SWPORTB_DR 0x0c
> +#define GPIO_SWPORTB_DDR 0x10
> +#define GPIO_SWPORTC_DR 0x18
> +#define GPIO_SWPORTC_DDR 0x1c
> +#define GPIO_SWPORTD_DR 0x24
> +#define GPIO_SWPORTD_DDR 0x28
> +#define GPIO_INTEN 0x30
> +#define GPIO_INTMASK 0x34
> +#define GPIO_INTTYPE_LEVEL 0x38
> +#define GPIO_INT_POLARITY 0x3c
> +#define GPIO_INTSTATUS 0x40
> +#define GPIO_PORTA_EOI 0x4c
> +#define GPIO_EXT_PORTA 0x50
> +#define GPIO_EXT_PORTB 0x54
> +#define GPIO_EXT_PORTC 0x58
> +#define GPIO_EXT_PORTD 0x5c
> +
> +#define DWAPB_MAX_PORTS 4
> +#define GPIO_EXT_PORT_SIZE (GPIO_EXT_PORTB - GPIO_EXT_PORTA)
> +#define GPIO_SWPORT_DR_SIZE (GPIO_SWPORTB_DR - GPIO_SWPORTA_DR)
> +#define GPIO_SWPORT_DDR_SIZE (GPIO_SWPORTB_DDR - GPIO_SWPORTA_DDR)
> +
> +struct dwapb_gpio;
> +
> +struct dwapb_gpio_port {
> + struct bgpio_chip bgc;
> + bool is_registered;
> + struct dwapb_gpio *gpio;
> +};
> +
> +struct dwapb_gpio {
> + struct device *dev;
> + void __iomem *regs;
> + struct dwapb_gpio_port *ports;
> + unsigned int nr_ports;
> + struct irq_domain *domain;
> +};
> +
> +static int dwapb_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
> +{
> + struct bgpio_chip *bgc = to_bgpio_chip(gc);
> + struct dwapb_gpio_port *port = container_of(bgc, struct
> + dwapb_gpio_port, bgc);
> + struct dwapb_gpio *gpio = port->gpio;
> +
> + return irq_find_mapping(gpio->domain, offset);
> +}
> +
> +static void dwapb_toggle_trigger(struct dwapb_gpio *gpio, unsigned int offs)
> +{
> + u32 v = readl(gpio->regs + GPIO_INT_POLARITY);
> +
> + if (gpio_get_value(gpio->ports[0].bgc.gc.base + offs))
> + v &= ~BIT(offs);
> + else
> + v |= BIT(offs);
> +
> + writel(v, gpio->regs + GPIO_INT_POLARITY);
> +}
> +
> +static void dwapb_irq_handler(u32 irq, struct irq_desc *desc)
> +{
> + struct dwapb_gpio *gpio = irq_get_handler_data(irq);
> + struct irq_chip *chip = irq_desc_get_chip(desc);
> + u32 irq_status = readl_relaxed(gpio->regs + GPIO_INTSTATUS);
> +
> + while (irq_status) {
> + int hwirq = fls(irq_status) - 1;
> + int gpio_irq = irq_find_mapping(gpio->domain, hwirq);
> +
> + generic_handle_irq(gpio_irq);
> + irq_status &= ~BIT(hwirq);
> +
> + if ((irq_get_trigger_type(gpio_irq) & IRQ_TYPE_SENSE_MASK)
> + == IRQ_TYPE_EDGE_BOTH)
> + dwapb_toggle_trigger(gpio, hwirq);
> + }
> +
> + if (chip->irq_eoi)
> + chip->irq_eoi(irq_desc_get_irq_data(desc));
> +}
> +
> +static void dwapb_irq_enable(struct irq_data *d)
> +{
> + struct irq_chip_generic *igc = irq_data_get_irq_chip_data(d);
> + struct dwapb_gpio *gpio = igc->private;
> + struct bgpio_chip *bgc = &gpio->ports[0].bgc;
> + unsigned long flags;
> + u32 val;
> +
> + spin_lock_irqsave(&bgc->lock, flags);
> + val = readl(gpio->regs + GPIO_INTEN);
> + val |= BIT(d->hwirq);
> + writel(val, gpio->regs + GPIO_INTEN);
> + spin_unlock_irqrestore(&bgc->lock, flags);
> +}
> +
> +static void dwapb_irq_disable(struct irq_data *d)
> +{
> + struct irq_chip_generic *igc = irq_data_get_irq_chip_data(d);
> + struct dwapb_gpio *gpio = igc->private;
> + struct bgpio_chip *bgc = &gpio->ports[0].bgc;
> + unsigned long flags;
> + u32 val;
> +
> + spin_lock_irqsave(&bgc->lock, flags);
> + val = readl(gpio->regs + GPIO_INTEN);
> + val &= ~BIT(d->hwirq);
> + writel(val, gpio->regs + GPIO_INTEN);
> + spin_unlock_irqrestore(&bgc->lock, flags);
> +}
> +
> +static unsigned int dwapb_irq_startup(struct irq_data *d)
> +{
> + struct irq_chip_generic *igc = irq_data_get_irq_chip_data(d);
> + struct dwapb_gpio *gpio = igc->private;
> + struct bgpio_chip *bgc = &gpio->ports[0].bgc;
> +
> + if (gpio_lock_as_irq(&bgc->gc, irqd_to_hwirq(d)))
> + dev_err(gpio->dev, "unable to lock HW IRQ %lu for IRQ\n",
> + irqd_to_hwirq(d));
> + dwapb_irq_enable(d);
> + return 0;
> +}
> +
> +static void dwapb_irq_shutdown(struct irq_data *d)
> +{
> + struct irq_chip_generic *igc = irq_data_get_irq_chip_data(d);
> + struct dwapb_gpio *gpio = igc->private;
> + struct bgpio_chip *bgc = &gpio->ports[0].bgc;
> +
> + dwapb_irq_disable(d);
> + gpio_unlock_as_irq(&bgc->gc, irqd_to_hwirq(d));
> +}
> +
> +static int dwapb_irq_set_type(struct irq_data *d, u32 type)
> +{
> + struct irq_chip_generic *igc = irq_data_get_irq_chip_data(d);
> + struct dwapb_gpio *gpio = igc->private;
> + struct bgpio_chip *bgc = &gpio->ports[0].bgc;
> + int bit = d->hwirq;
> + unsigned long level, polarity, flags;
> +
> + if (type & ~(IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING |
> + IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW))
> + return -EINVAL;
> +
> + spin_lock_irqsave(&bgc->lock, flags);
> + level = readl(gpio->regs + GPIO_INTTYPE_LEVEL);
> + polarity = readl(gpio->regs + GPIO_INT_POLARITY);
> +
> + switch (type) {
> + case IRQ_TYPE_EDGE_BOTH:
> + level |= BIT(bit);
> + dwapb_toggle_trigger(gpio, bit);
> + break;
> + case IRQ_TYPE_EDGE_RISING:
> + level |= BIT(bit);
> + polarity |= BIT(bit);
> + break;
> + case IRQ_TYPE_EDGE_FALLING:
> + level |= BIT(bit);
> + polarity &= ~BIT(bit);
> + break;
> + case IRQ_TYPE_LEVEL_HIGH:
> + level &= ~BIT(bit);
> + polarity |= BIT(bit);
> + break;
> + case IRQ_TYPE_LEVEL_LOW:
> + level &= ~BIT(bit);
> + polarity &= ~BIT(bit);
> + break;
> + }
> +
> + writel(level, gpio->regs + GPIO_INTTYPE_LEVEL);
> + writel(polarity, gpio->regs + GPIO_INT_POLARITY);
> + spin_unlock_irqrestore(&bgc->lock, flags);
> +
> + return 0;
> +}
> +
> +static void dwapb_configure_irqs(struct dwapb_gpio *gpio,
> + struct dwapb_gpio_port *port)
> +{
> + struct gpio_chip *gc = &port->bgc.gc;
> + struct device_node *node = gc->of_node;
> + struct irq_chip_generic *irq_gc;
> + unsigned int hwirq, ngpio = gc->ngpio;
> + struct irq_chip_type *ct;
> + int err, irq;
> +
> + irq = irq_of_parse_and_map(node, 0);
> + if (!irq) {
> + dev_warn(gpio->dev, "no irq for bank %s\n",
> + port->bgc.gc.of_node->full_name);
> + return;
> + }
> +
> + gpio->domain = irq_domain_add_linear(node, ngpio,
> + &irq_generic_chip_ops, gpio);
> + if (!gpio->domain)
> + return;
> +
> + err = irq_alloc_domain_generic_chips(gpio->domain, ngpio, 1,
> + "gpio-dwapb", handle_level_irq,
> + IRQ_NOREQUEST, 0,
> + IRQ_GC_INIT_NESTED_LOCK);
> + if (err) {
> + dev_info(gpio->dev, "irq_alloc_domain_generic_chips failed\n");
> + irq_domain_remove(gpio->domain);
> + gpio->domain = NULL;
> + return;
> + }
> +
> + irq_gc = irq_get_domain_generic_chip(gpio->domain, 0);
> + if (!irq_gc) {
> + irq_domain_remove(gpio->domain);
> + gpio->domain = NULL;
> + return;
> + }
> +
> + irq_gc->reg_base = gpio->regs;
> + irq_gc->private = gpio;
> +
> + ct = irq_gc->chip_types;
> + ct->chip.irq_ack = irq_gc_ack_set_bit;
> + ct->chip.irq_mask = irq_gc_mask_set_bit;
> + ct->chip.irq_unmask = irq_gc_mask_clr_bit;
> + ct->chip.irq_set_type = dwapb_irq_set_type;
> + ct->chip.irq_enable = dwapb_irq_enable;
> + ct->chip.irq_disable = dwapb_irq_disable;
> + ct->chip.irq_startup = dwapb_irq_startup;
> + ct->chip.irq_shutdown = dwapb_irq_shutdown;
> + ct->regs.ack = GPIO_PORTA_EOI;
> + ct->regs.mask = GPIO_INTMASK;
> +
> + irq_setup_generic_chip(irq_gc, IRQ_MSK(port->bgc.gc.ngpio),
> + IRQ_GC_INIT_NESTED_LOCK, IRQ_NOREQUEST, 0);
> +
> + irq_set_chained_handler(irq, dwapb_irq_handler);
> + irq_set_handler_data(irq, gpio);
> +
> + for (hwirq = 0 ; hwirq < ngpio ; hwirq++)
> + irq_create_mapping(gpio->domain, hwirq);
> +
> + port->bgc.gc.to_irq = dwapb_gpio_to_irq;
> +}
> +
> +static void dwapb_irq_teardown(struct dwapb_gpio *gpio)
> +{
> + struct dwapb_gpio_port *port = &gpio->ports[0];
> + struct gpio_chip *gc = &port->bgc.gc;
> + unsigned int ngpio = gc->ngpio;
> + irq_hw_number_t hwirq;
> +
> + if (!gpio->domain)
> + return;
> +
> + for (hwirq = 0 ; hwirq < ngpio ; hwirq++)
> + irq_dispose_mapping(irq_find_mapping(gpio->domain, hwirq));
> +
> + irq_domain_remove(gpio->domain);
> + gpio->domain = NULL;
> +}
> +
> +static int dwapb_gpio_add_port(struct dwapb_gpio *gpio,
> + struct device_node *port_np,
> + unsigned int offs)
> +{
> + struct dwapb_gpio_port *port;
> + u32 port_idx, ngpio;
> + void __iomem *dat, *set, *dirout;
> + int err;
> +
> + if (of_property_read_u32(port_np, "reg", &port_idx) ||
> + port_idx >= DWAPB_MAX_PORTS) {
> + dev_err(gpio->dev, "missing/invalid port index for %s\n",
> + port_np->full_name);
> + return -EINVAL;
> + }
> +
> + port = &gpio->ports[offs];
> + port->gpio = gpio;
> +
> + if (of_property_read_u32(port_np, "snps,nr-gpios", &ngpio)) {
> + dev_info(gpio->dev, "failed to get number of gpios for %s\n",
> + port_np->full_name);
> + ngpio = 32;
> + }
> +
> + dat = gpio->regs + GPIO_EXT_PORTA + (port_idx * GPIO_EXT_PORT_SIZE);
> + set = gpio->regs + GPIO_SWPORTA_DR + (port_idx * GPIO_SWPORT_DR_SIZE);
> + dirout = gpio->regs + GPIO_SWPORTA_DDR +
> + (port_idx * GPIO_SWPORT_DDR_SIZE);
> +
> + err = bgpio_init(&port->bgc, gpio->dev, 4, dat, set, NULL, dirout,
> + NULL, false);
> + if (err) {
> + dev_err(gpio->dev, "failed to init gpio chip for %s\n",
> + port_np->full_name);
> + return err;
> + }
> +
> + port->bgc.gc.ngpio = ngpio;
> + port->bgc.gc.of_node = port_np;
> +
> + /*
> + * Only port A can provide interrupts in all configurations of the IP.
> + */
> + if (port_idx == 0 &&
> + of_property_read_bool(port_np, "interrupt-controller"))
> + dwapb_configure_irqs(gpio, port);
> +
> + err = gpiochip_add(&port->bgc.gc);
> + if (err)
> + dev_err(gpio->dev, "failed to register gpiochip for %s\n",
> + port_np->full_name);
> + else
> + port->is_registered = true;
> +
> + return err;
> +}
> +
> +static void dwapb_gpio_unregister(struct dwapb_gpio *gpio)
> +{
> + unsigned int m;
> +
> + for (m = 0; m < gpio->nr_ports; ++m)
> + if (gpio->ports[m].is_registered)
> + WARN_ON(gpiochip_remove(&gpio->ports[m].bgc.gc));
> +}
> +
> +static int dwapb_gpio_probe(struct platform_device *pdev)
> +{
> + struct resource *res;
> + struct dwapb_gpio *gpio;
> + struct device_node *np;
> + int err;
> + unsigned int offs = 0;
> +
> + gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
> + if (!gpio)
> + return -ENOMEM;
> + gpio->dev = &pdev->dev;
> +
> + gpio->nr_ports = of_get_child_count(pdev->dev.of_node);
> + if (!gpio->nr_ports) {
> + err = -EINVAL;
> + goto out_err;
> + }
> + gpio->ports = devm_kzalloc(&pdev->dev, gpio->nr_ports *
> + sizeof(*gpio->ports), GFP_KERNEL);
> + if (!gpio->ports) {
> + err = -ENOMEM;
> + goto out_err;
> + }
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + gpio->regs = devm_ioremap_resource(&pdev->dev, res);
> + if (IS_ERR(gpio->regs)) {
> + err = PTR_ERR(gpio->regs);
> + goto out_err;
> + }
> +
> + for_each_child_of_node(pdev->dev.of_node, np) {
> + err = dwapb_gpio_add_port(gpio, np, offs++);
> + if (err)
> + goto out_unregister;
> + }
> + platform_set_drvdata(pdev, gpio);
> +
> + return 0;
> +
> +out_unregister:
> + dwapb_gpio_unregister(gpio);
> + dwapb_irq_teardown(gpio);
> +
> +out_err:
> + return err;
> +}
> +
> +static int dwapb_gpio_remove(struct platform_device *pdev)
> +{
> + struct dwapb_gpio *gpio = platform_get_drvdata(pdev);
> +
> + dwapb_gpio_unregister(gpio);
> + dwapb_irq_teardown(gpio);
> +
> + return 0;
> +}
> +
> +static const struct of_device_id dwapb_of_match[] = {
> + { .compatible = "snps,dw-apb-gpio" },
> + { /* Sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, dwapb_of_match);
> +
> +static struct platform_driver dwapb_gpio_driver = {
> + .driver = {
> + .name = "gpio-dwapb",
> + .owner = THIS_MODULE,
> + .of_match_table = of_match_ptr(dwapb_of_match),
> + },
> + .probe = dwapb_gpio_probe,
> + .remove = dwapb_gpio_remove,
> +};
> +
> +module_platform_driver(dwapb_gpio_driver);
> +
> +MODULE_LICENSE("GPL");
> +MODULE_AUTHOR("Jamie Iles");
> +MODULE_DESCRIPTION("Synopsys DesignWare APB GPIO driver");
> --
> 1.7.9.5
>
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