Re: [PATCH v3 08/10] gpio: Add gpio driver for Actions OWL S900 SoC

[Andy Shevchenko <andy.shevchenko@gmail.com>]

On Wed, Feb 28, 2018 at 8:14 PM, Manivannan Sadhasivam
<manivannan.sadhasivam@linaro.org> wrote:
> Add gpio driver for Actions Semi OWL family S900 SoC. Set of registers
> controlling the gpio shares the same register range with pinctrl block.
>
> GPIO registers are organized as 6 banks and each bank controls the
> maximum of 32 gpios.
>

FWIW,
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>

P.S. Comma in terminator line is not needed.

> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
> ---
>  drivers/gpio/Kconfig    |   8 ++
>  drivers/gpio/Makefile   |   1 +
>  drivers/gpio/gpio-owl.c | 218 ++++++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 227 insertions(+)
>  create mode 100644 drivers/gpio/gpio-owl.c
>
> diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
> index 8dbb2280538d..09ceb98e2434 100644
> --- a/drivers/gpio/Kconfig
> +++ b/drivers/gpio/Kconfig
> @@ -364,6 +364,14 @@ config GPIO_OMAP
>         help
>           Say yes here to enable GPIO support for TI OMAP SoCs.
>
> +config GPIO_OWL
> +       tristate "Actions OWL GPIO support"
> +       default ARCH_ACTIONS
> +       depends on ARCH_ACTIONS || COMPILE_TEST
> +       depends on OF_GPIO
> +       help
> +         Say yes here to enable GPIO support for Actions OWL SoCs.
> +
>  config GPIO_PL061
>         bool "PrimeCell PL061 GPIO support"
>         depends on ARM_AMBA
> diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
> index cccb0d40846c..b2bb11d4675f 100644
> --- a/drivers/gpio/Makefile
> +++ b/drivers/gpio/Makefile
> @@ -91,6 +91,7 @@ obj-$(CONFIG_GPIO_MXC)                += gpio-mxc.o
>  obj-$(CONFIG_GPIO_MXS)         += gpio-mxs.o
>  obj-$(CONFIG_GPIO_OCTEON)      += gpio-octeon.o
>  obj-$(CONFIG_GPIO_OMAP)                += gpio-omap.o
> +obj-$(CONFIG_GPIO_OWL)         += gpio-owl.o
>  obj-$(CONFIG_GPIO_PCA953X)     += gpio-pca953x.o
>  obj-$(CONFIG_GPIO_PCF857X)     += gpio-pcf857x.o
>  obj-$(CONFIG_GPIO_PCH)         += gpio-pch.o
> diff --git a/drivers/gpio/gpio-owl.c b/drivers/gpio/gpio-owl.c
> new file mode 100644
> index 000000000000..98f2e98197bc
> --- /dev/null
> +++ b/drivers/gpio/gpio-owl.c
> @@ -0,0 +1,218 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * OWL SoC's GPIO driver
> + *
> + * Copyright (c) 2018 Linaro Ltd.
> + * Author: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
> + */
> +
> +#include <linux/bitops.h>
> +#include <linux/err.h>
> +#include <linux/gpio/driver.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/of_address.h>
> +#include <linux/of_device.h>
> +#include <linux/platform_device.h>
> +#include <linux/slab.h>
> +
> +#define GPIO_OUTEN     0x0000
> +#define GPIO_INEN      0x0004
> +#define GPIO_DAT       0x0008
> +
> +#define OWL_GPIO_PORT_A 0
> +#define OWL_GPIO_PORT_B 1
> +#define OWL_GPIO_PORT_C 2
> +#define OWL_GPIO_PORT_D 3
> +#define OWL_GPIO_PORT_E 4
> +#define OWL_GPIO_PORT_F 5
> +
> +struct owl_gpio_port {
> +       const char *name;
> +       unsigned int offset;
> +       unsigned int pins;
> +};
> +
> +struct owl_gpio {
> +       struct gpio_chip gpio;
> +       const struct owl_gpio_port *port;
> +       void __iomem *base;
> +       int id;
> +};
> +
> +static void owl_gpio_set_reg(void __iomem *base, unsigned int pin, int flag)
> +{
> +       u32 val;
> +
> +       val = readl_relaxed(base);
> +
> +       if (flag)
> +               val |= BIT(pin);
> +       else
> +               val &= ~BIT(pin);
> +
> +       writel_relaxed(val, base);
> +}
> +
> +static int owl_gpio_request(struct gpio_chip *chip, unsigned int offset)
> +{
> +       struct owl_gpio *gpio = gpiochip_get_data(chip);
> +       const struct owl_gpio_port *port = gpio->port;
> +       void __iomem *gpio_base = gpio->base + port->offset;
> +
> +       /*
> +        * GPIOs have higher priority over other modules, so either setting
> +        * them as OUT or IN is sufficient
> +        */
> +       owl_gpio_set_reg(gpio_base + GPIO_OUTEN, offset, true);
> +
> +       return 0;
> +}
> +
> +static void owl_gpio_free(struct gpio_chip *chip, unsigned int offset)
> +{
> +       struct owl_gpio *gpio = gpiochip_get_data(chip);
> +       const struct owl_gpio_port *port = gpio->port;
> +       void __iomem *gpio_base = gpio->base + port->offset;
> +
> +       /* disable gpio output */
> +       owl_gpio_set_reg(gpio_base + GPIO_OUTEN, offset, false);
> +
> +       /* disable gpio input */
> +       owl_gpio_set_reg(gpio_base + GPIO_INEN, offset, false);
> +}
> +
> +static int owl_gpio_get(struct gpio_chip *chip, unsigned int offset)
> +{
> +       struct owl_gpio *gpio = gpiochip_get_data(chip);
> +       const struct owl_gpio_port *port = gpio->port;
> +       void __iomem *gpio_base = gpio->base + port->offset;
> +       u32 val;
> +
> +       val = readl_relaxed(gpio_base + GPIO_DAT);
> +
> +       return !!(val & BIT(offset));
> +}
> +
> +static void owl_gpio_set(struct gpio_chip *chip, unsigned int offset, int value)
> +{
> +       struct owl_gpio *gpio = gpiochip_get_data(chip);
> +       const struct owl_gpio_port *port = gpio->port;
> +       void __iomem *gpio_base = gpio->base + port->offset;
> +       u32 val;
> +
> +       val = readl_relaxed(gpio_base + GPIO_DAT);
> +
> +       if (value)
> +               val |= BIT(offset);
> +       else
> +               val &= ~BIT(offset);
> +
> +       writel_relaxed(val, gpio_base + GPIO_DAT);
> +}
> +
> +static int owl_gpio_direction_input(struct gpio_chip *chip, unsigned int offset)
> +{
> +       struct owl_gpio *gpio = gpiochip_get_data(chip);
> +       const struct owl_gpio_port *port = gpio->port;
> +       void __iomem *gpio_base = gpio->base + port->offset;
> +
> +       owl_gpio_set_reg(gpio_base + GPIO_OUTEN, offset, false);
> +       owl_gpio_set_reg(gpio_base + GPIO_INEN, offset, true);
> +
> +       return 0;
> +}
> +
> +static int owl_gpio_direction_output(struct gpio_chip *chip,
> +                               unsigned int offset, int value)
> +{
> +       struct owl_gpio *gpio = gpiochip_get_data(chip);
> +       const struct owl_gpio_port *port = gpio->port;
> +       void __iomem *gpio_base = gpio->base + port->offset;
> +
> +       owl_gpio_set_reg(gpio_base + GPIO_INEN, offset, false);
> +       owl_gpio_set_reg(gpio_base + GPIO_OUTEN, offset, true);
> +       owl_gpio_set(chip, offset, value);
> +
> +       return 0;
> +}
> +
> +#define OWL_GPIO_PORT(port, base, count)               \
> +       [OWL_GPIO_PORT_##port] = {                      \
> +               .name = #port,                          \
> +               .offset = base,                         \
> +               .pins = count,                          \
> +       }
> +
> +static const struct owl_gpio_port s900_gpio_ports[] = {
> +       OWL_GPIO_PORT(A, 0x0000, 32),
> +       OWL_GPIO_PORT(B, 0x000C, 32),
> +       OWL_GPIO_PORT(C, 0x0018, 12),
> +       OWL_GPIO_PORT(D, 0x0024, 30),
> +       OWL_GPIO_PORT(E, 0x0030, 32),
> +       OWL_GPIO_PORT(F, 0x00F0, 8),
> +};
> +
> +static int owl_gpio_probe(struct platform_device *pdev)
> +{
> +       struct owl_gpio *gpio;
> +       const struct owl_gpio_port *port;
> +       int ret;
> +
> +       gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
> +       if (!gpio)
> +               return -ENOMEM;
> +
> +       gpio->base = of_iomap(pdev->dev.of_node, 0);
> +       if (IS_ERR(gpio->base))
> +               return PTR_ERR(gpio->base);
> +
> +       gpio->id = of_alias_get_id(pdev->dev.of_node, "gpio");
> +       if (gpio->id < 0)
> +               return gpio->id;
> +
> +       port = &s900_gpio_ports[gpio->id];
> +
> +       gpio->gpio.request = owl_gpio_request;
> +       gpio->gpio.free = owl_gpio_free;
> +       gpio->gpio.get = owl_gpio_get;
> +       gpio->gpio.set = owl_gpio_set;
> +       gpio->gpio.direction_input = owl_gpio_direction_input;
> +       gpio->gpio.direction_output = owl_gpio_direction_output;
> +
> +       gpio->gpio.base = -1;
> +       gpio->gpio.parent = &pdev->dev;
> +       gpio->gpio.label = port->name;
> +       gpio->gpio.ngpio = port->pins;
> +
> +       gpio->port = port;
> +
> +       platform_set_drvdata(pdev, gpio);
> +
> +       ret = devm_gpiochip_add_data(&pdev->dev, &gpio->gpio, gpio);
> +       if (ret < 0) {
> +               dev_err(&pdev->dev, "Failed to register gpiochip\n");
> +               return ret;
> +       }
> +
> +       return 0;
> +}
> +
> +static const struct of_device_id owl_gpio_of_match[] = {
> +       { .compatible = "actions,s900-gpio", },
> +       { /* sentinel */ },
> +};
> +MODULE_DEVICE_TABLE(of, owl_gpio_of_match);
> +
> +static struct platform_driver owl_gpio_driver = {
> +       .driver         = {
> +               .name   = "owl-gpio",
> +               .of_match_table = owl_gpio_of_match,
> +       },
> +       .probe          = owl_gpio_probe,
> +};
> +module_platform_driver(owl_gpio_driver);
> +
> +MODULE_AUTHOR("Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>");
> +MODULE_DESCRIPTION("Actions Semi OWL SoCs GPIO driver");
> +MODULE_LICENSE("GPL");
> --
> 2.14.1
>



-- 
With Best Regards,
Andy Shevchenko