Re: [PATCH v2 2/2] gpio: Add xgs-iproc driver

Bartosz Golaszewski
2019-10-17T15:17:18Z

czw., 17 paź 2019 o 05:11 Chris Packham
<chris.packham@alliedtelesis.co.nz> napisał(a):
>
> This driver supports the Chip Common A GPIO controller present on a
> number of Broadcom switch ASICs with integrated SoCs. The controller is
> similar to the pinctrl-nsp-gpio and pinctrl-iproc-gpio blocks but
> different enough that a separate driver is required.
>
> This has been ported from Broadcom's XLDK 5.0.3 retaining only the CCA
> support (pinctrl-iproc-gpio covers CCB).
>
> Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
> ---
>
> Notes:
> Changes in v2:
> - use more of the generic infrastructure for gpio chips
> - handling the root interrupt is still done manually due to sharing with uart0.
>
> drivers/gpio/Kconfig | 9 +
> drivers/gpio/Makefile | 1 +
> drivers/gpio/gpio-xgs-iproc.c | 301 ++++++++++++++++++++++++++++++++++
> 3 files changed, 311 insertions(+)
> create mode 100644 drivers/gpio/gpio-xgs-iproc.c
>
> diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
> index 38e096e6925f..4b3c0f8397d7 100644
> --- a/drivers/gpio/Kconfig
> +++ b/drivers/gpio/Kconfig
> @@ -156,6 +156,15 @@ config GPIO_BRCMSTB
> help
> Say yes here to enable GPIO support for Broadcom STB (BCM7XXX) SoCs.
>
> +config GPIO_XGS_IPROC
> + tristate "BRCM XGS iProc GPIO support"
> + depends on OF_GPIO && (ARCH_BCM_IPROC || COMPILE_TEST)
> + select GPIO_GENERIC
> + select GPIOLIB_IRQCHIP
> + default ARCH_BCM_IPROC
> + help
> + Say yes here to enable GPIO support for Broadcom XGS iProc SoCs.
> +
> config GPIO_CADENCE
> tristate "Cadence GPIO support"
> depends on OF_GPIO
> diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
> index d2fd19c15bae..3783c3d43fbe 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_BD70528) += gpio-bd70528.o
> obj-$(CONFIG_GPIO_BD9571MWV) += gpio-bd9571mwv.o
> obj-$(CONFIG_GPIO_BRCMSTB) += gpio-brcmstb.o
> +obj-$(CONFIG_GPIO_XGS_IPROC) += gpio-xgs-iproc.o
> obj-$(CONFIG_GPIO_BT8XX) += gpio-bt8xx.o
> obj-$(CONFIG_GPIO_CADENCE) += gpio-cadence.o
> obj-$(CONFIG_GPIO_CLPS711X) += gpio-clps711x.o
> diff --git a/drivers/gpio/gpio-xgs-iproc.c b/drivers/gpio/gpio-xgs-iproc.c
> new file mode 100644
> index 000000000000..a0277acf9369
> --- /dev/null
> +++ b/drivers/gpio/gpio-xgs-iproc.c
> @@ -0,0 +1,301 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2017 Broadcom Corporation
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/init.h>
> +#include <linux/module.h>
> +#include <linux/irq.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/ioport.h>
> +#include <linux/of_device.h>
> +#include <linux/of_address.h>
> +#include <linux/of_gpio.h>

None of these of_ headers seem to be needed.

> +
> +#define CCA_INT_F_GPIOINT BIT(0)
> +#define CCA_INT_STS 0x20
> +#define CCA_INT_MASK 0x24
> +
> +#define GPIO_CCA_DIN 0x0
> +#define GPIO_CCA_DOUT 0x4
> +#define GPIO_CCA_OUT_EN 0x8
> +#define GPIO_CCA_INT_LEVEL 0x10
> +#define GPIO_CCA_INT_LEVEL_MASK 0x14
> +#define GPIO_CCA_INT_EVENT 0x18
> +#define GPIO_CCA_INT_EVENT_MASK 0x1C
> +#define GPIO_CCA_INT_EDGE 0x24

Please use a common prefix for all symbols.

> +
> +struct iproc_gpio_chip {
> + struct irq_chip irqchip;
> + struct gpio_chip gc;
> + spinlock_t lock;

You're not using this lock anywhere.

> + struct device *dev;
> + void __iomem *base;
> + void __iomem *intr;
> +};
> +
> +static inline struct iproc_gpio_chip *
> +to_iproc_gpio(struct gpio_chip *gc)
> +{
> + return container_of(gc, struct iproc_gpio_chip, gc);
> +}
> +
> +static void iproc_gpio_irq_ack(struct irq_data *d)
> +{
> + struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
> + struct iproc_gpio_chip *chip = to_iproc_gpio(gc);
> + int pin = d->hwirq;
> + u32 irq = d->irq;
> + u32 irq_type, event_status = 0;
> +
> + irq_type = irq_get_trigger_type(irq);
> + if (irq_type & IRQ_TYPE_EDGE_BOTH) {
> + event_status |= BIT(pin);
> + writel(event_status, chip->base + GPIO_CCA_INT_EVENT);
> + }
> +}
> +
> +static void iproc_gpio_irq_unmask(struct irq_data *d)
> +{
> + struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
> + struct iproc_gpio_chip *chip = to_iproc_gpio(gc);
> + int pin = d->hwirq;
> + u32 irq = d->irq;
> + u32 int_mask, irq_type, event_mask;
> +
> + irq_type = irq_get_trigger_type(irq);
> + event_mask = readl(chip->base + GPIO_CCA_INT_EVENT_MASK);

Do you really need to use the non-relaxed versions of readl() and writel()?

> + int_mask = readl(chip->base + GPIO_CCA_INT_LEVEL_MASK);
> +
> + if (irq_type & IRQ_TYPE_EDGE_BOTH) {
> + event_mask |= 1 << pin;
> + writel(event_mask, chip->base + GPIO_CCA_INT_EVENT_MASK);
> + } else {
> + int_mask |= 1 << pin;
> + writel(int_mask, chip->base + GPIO_CCA_INT_LEVEL_MASK);
> + }
> +}
> +
> +static void iproc_gpio_irq_mask(struct irq_data *d)
> +{
> + struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
> + struct iproc_gpio_chip *chip = to_iproc_gpio(gc);
> + int pin = d->hwirq;
> + u32 irq = d->irq;
> + u32 irq_type, int_mask, event_mask;
> +
> + irq_type = irq_get_trigger_type(irq);
> + event_mask = readl(chip->base + GPIO_CCA_INT_EVENT_MASK);
> + int_mask = readl(chip->base + GPIO_CCA_INT_LEVEL_MASK);
> +
> + if (irq_type & IRQ_TYPE_EDGE_BOTH) {
> + event_mask &= ~BIT(pin);
> + writel(event_mask, chip->base + GPIO_CCA_INT_EVENT_MASK);
> + } else {
> + int_mask &= ~BIT(pin);
> + writel(int_mask, chip->base + GPIO_CCA_INT_LEVEL_MASK);
> + }
> +}
> +
> +
> +static int iproc_gpio_irq_set_type(struct irq_data *d, u32 type)
> +{
> + struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
> + struct iproc_gpio_chip *chip = to_iproc_gpio(gc);
> + int pin = d->hwirq;
> + u32 irq = d->irq;
> + u32 event_pol, int_pol;
> +

Remove the extra newline.

Bart

> +
> + switch (type & IRQ_TYPE_SENSE_MASK) {
> + case IRQ_TYPE_EDGE_RISING:
> + event_pol = readl(chip->base + GPIO_CCA_INT_EDGE);
> + event_pol &= ~BIT(pin);
> + writel(event_pol, chip->base + GPIO_CCA_INT_EDGE);
> + break;
> + case IRQ_TYPE_EDGE_FALLING:
> + event_pol = readl(chip->base + GPIO_CCA_INT_EDGE);
> + event_pol |= BIT(pin);
> + writel(event_pol, chip->base + GPIO_CCA_INT_EDGE);
> + break;
> + case IRQ_TYPE_LEVEL_HIGH:
> + int_pol = readl(chip->base + GPIO_CCA_INT_LEVEL);
> + int_pol &= ~BIT(pin);
> + writel(int_pol, chip->base + GPIO_CCA_INT_LEVEL);
> + break;
> + case IRQ_TYPE_LEVEL_LOW:
> + int_pol = readl(chip->base + GPIO_CCA_INT_LEVEL);
> + int_pol |= BIT(pin);
> + writel(int_pol, chip->base + GPIO_CCA_INT_LEVEL);
> + break;
> + default:
> + /* should not come here */
> + return -EINVAL;
> + }
> +
> + if (type & IRQ_TYPE_LEVEL_MASK)
> + irq_set_handler_locked(irq_get_irq_data(irq), handle_level_irq);
> + else if (type & IRQ_TYPE_EDGE_BOTH)
> + irq_set_handler_locked(irq_get_irq_data(irq), handle_edge_irq);
> +
> + return 0;
> +}
> +
> +static irqreturn_t iproc_gpio_irq_handler(int irq, void *data)
> +{
> + struct gpio_chip *gc = (struct gpio_chip *)data;
> + struct iproc_gpio_chip *chip = to_iproc_gpio(gc);
> + int bit;
> + unsigned long int_bits = 0;
> + u32 int_status;
> +
> + /* go through the entire GPIOs and handle all interrupts */
> + int_status = readl(chip->intr + CCA_INT_STS);
> + if (int_status & CCA_INT_F_GPIOINT) {
> + u32 event, level;
> +
> + /* Get level and edge interrupts */
> + event = readl(chip->base + GPIO_CCA_INT_EVENT_MASK);
> + event &= readl(chip->base + GPIO_CCA_INT_EVENT);
> + level = readl(chip->base + GPIO_CCA_DIN);
> + level ^= readl(chip->base + GPIO_CCA_INT_LEVEL);
> + level &= readl(chip->base + GPIO_CCA_INT_LEVEL_MASK);
> + int_bits = level | event;
> +
> + for_each_set_bit(bit, &int_bits, gc->ngpio)
> + generic_handle_irq(
> + irq_linear_revmap(gc->irq.domain, bit));
> + }
> +
> + return int_bits ? IRQ_HANDLED : IRQ_NONE;
> +}
> +
> +static int iproc_gpio_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct device_node *dn = pdev->dev.of_node;
> + struct iproc_gpio_chip *chip;
> + u32 num_gpios;
> + int irq, ret;
> +
> + chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
> + if (!chip)
> + return -ENOMEM;
> +
> + chip->dev = dev;
> + platform_set_drvdata(pdev, chip);
> +
> + chip->base = devm_platform_ioremap_resource(pdev, 0);
> + if (IS_ERR(chip->base))
> + return PTR_ERR(chip->base);
> +
> + ret = bgpio_init(&chip->gc, dev, 4,
> + chip->base + GPIO_CCA_DIN,
> + chip->base + GPIO_CCA_DOUT,
> + NULL,
> + chip->base + GPIO_CCA_OUT_EN,
> + NULL,
> + 0);
> + if (ret) {
> + dev_err(dev, "unable to init GPIO chip\n");
> + return ret;
> + }
> +
> + chip->gc.label = dev_name(dev);
> + if (of_property_read_u32(dn, "ngpios", &num_gpios))
> + chip->gc.ngpio = num_gpios;
> +
> + irq = platform_get_irq(pdev, 0);
> + if (irq > 0) {
> + struct gpio_irq_chip *girq;
> + struct irq_chip *irqc;
> + u32 val;
> +
> + irqc = &chip->irqchip;
> + irqc->name = dev_name(dev);
> + irqc->irq_ack = iproc_gpio_irq_ack;
> + irqc->irq_mask = iproc_gpio_irq_mask;
> + irqc->irq_unmask = iproc_gpio_irq_unmask;
> + irqc->irq_set_type = iproc_gpio_irq_set_type;
> +
> + chip->intr = devm_platform_ioremap_resource(pdev, 1);
> + if (IS_ERR(chip->intr))
> + return PTR_ERR(chip->intr);
> +
> + /* Enable GPIO interrupts for CCA GPIO */
> + val = readl(chip->intr + CCA_INT_MASK);
> + val |= CCA_INT_F_GPIOINT;
> + writel(val, chip->intr + CCA_INT_MASK);
> +
> + /*
> + * Directly request the irq here instead of passing
> + * a flow-handler to gpiochip_set_chained_irqchip,
> + * because the irq is shared.
> + */
> + ret = devm_request_irq(dev, irq, iproc_gpio_irq_handler,
> + IRQF_SHARED, chip->gc.label, &chip->gc);
> + if (ret) {
> + dev_err(dev, "Fail to request IRQ%d: %d\n", irq, ret);
> + return ret;
> + }
> +
> + girq = &chip->gc.irq;
> + girq->chip = irqc;
> + /* This will let us handle the parent IRQ in the driver */
> + girq->parent_handler = NULL;
> + girq->num_parents = 0;
> + girq->parents = NULL;
> + girq->default_type = IRQ_TYPE_NONE;
> + girq->handler = handle_simple_irq;
> + }
> +
> + ret = devm_gpiochip_add_data(dev, &chip->gc, chip);
> + if (ret) {
> + dev_err(dev, "unable to add GPIO chip\n");
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int __exit iproc_gpio_remove(struct platform_device *pdev)
> +{
> + struct iproc_gpio_chip *chip;
> +
> + chip = platform_get_drvdata(pdev);
> + if (!chip)
> + return -ENODEV;
> +
> + if (chip->intr) {
> + u32 val;
> +
> + val = readl(chip->intr + CCA_INT_MASK);
> + val &= ~CCA_INT_F_GPIOINT;
> + writel(val, chip->intr + CCA_INT_MASK);
> + }
> +
> + return 0;
> +}
> +
> +static const struct of_device_id bcm_iproc_gpio_of_match[] __initconst = {
> + { .compatible = "brcm,iproc-gpio-cca" },
> + {}
> +};
> +MODULE_DEVICE_TABLE(of, bcm_iproc_gpio_of_match);
> +
> +static struct platform_driver bcm_iproc_gpio_driver = {
> + .driver = {
> + .name = "iproc-xgs-gpio",
> + .owner = THIS_MODULE,
> + .of_match_table = bcm_iproc_gpio_of_match,
> + },
> + .probe = iproc_gpio_probe,
> + .remove = iproc_gpio_remove,
> +};
> +
> +module_platform_driver(bcm_iproc_gpio_driver);
> +
> +MODULE_DESCRIPTION("XGS IPROC GPIO driver");
> +MODULE_LICENSE("GPL v2");
> --
> 2.23.0
>