[U-Boot] [PATCH 1/2] gpio: Add DW APB GPIO driver

[Simon Glass]

Hi Marek,

On 27 July 2015 at 14:44, Marek Vasut <marex at denx.de> wrote:
> Add driver for the DesignWare APB GPIO IP block.
> This driver is DM capable and probes from DT.
>
> Signed-off-by: Marek Vasut <marex at denx.de>
> Cc: Simon Glass <sjg at chromium.org>
> ---
>  drivers/gpio/Makefile     |   1 +
>  drivers/gpio/dwapb_gpio.c | 167 ++++++++++++++++++++++++++++++++++++++++++++++
>  2 files changed, 168 insertions(+)
>  create mode 100644 drivers/gpio/dwapb_gpio.c
>
> diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
> index 67c6374..603c96b 100644
> --- a/drivers/gpio/Makefile
> +++ b/drivers/gpio/Makefile
> @@ -6,6 +6,7 @@
>  #
>
>  ifndef CONFIG_SPL_BUILD
> +obj-$(CONFIG_DWAPB_GPIO)       += dwapb_gpio.o
>  obj-$(CONFIG_AXP_GPIO)         += axp_gpio.o
>  endif
>  obj-$(CONFIG_DM_GPIO)          += gpio-uclass.o
> diff --git a/drivers/gpio/dwapb_gpio.c b/drivers/gpio/dwapb_gpio.c
> new file mode 100644
> index 0000000..cdb6e78
> --- /dev/null
> +++ b/drivers/gpio/dwapb_gpio.c
> @@ -0,0 +1,167 @@
> +/*
> + * (C) Copyright 2015 Marek Vasut <marex at denx.de>
> + *
> + * DesignWare APB GPIO driver
> + *
> + * SPDX-License-Identifier:    GPL-2.0+
> + */
> +
> +#include <common.h>
> +#include <malloc.h>
> +#include <asm/arch/gpio.h>
> +#include <asm/gpio.h>
> +#include <asm/io.h>
> +#include <dm.h>
> +#include <dm/device-internal.h>
> +#include <dm/lists.h>
> +#include <dm/root.h>
> +#include <errno.h>
> +
> +DECLARE_GLOBAL_DATA_PTR;
> +
> +#define GPIO_SWPORTA_DR                0x00
> +#define GPIO_SWPORTA_DDR       0x04
> +#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_DEBOUNCE    0x48
> +#define GPIO_PORTA_EOI         0x4c
> +#define GPIO_EXT_PORTA         0x50

Should use C structure, right?

> +
> +struct gpio_dwapb_platdata {
> +       char            name[24];
> +       int             bank;
> +       int             pins;
> +       fdt_addr_t      base;
> +};
> +
> +static int dwapb_gpio_direction_input(struct udevice *dev, unsigned pin)
> +{
> +       struct gpio_dwapb_platdata *plat = dev_get_platdata(dev);

blank line after declarations

> +       clrbits_le32(plat->base + GPIO_SWPORTA_DDR, 1 << pin);
> +       return 0;
> +}
> +
> +static int dwapb_gpio_direction_output(struct udevice *dev, unsigned pin,
> +                                    int val)
> +{
> +       struct gpio_dwapb_platdata *plat = dev_get_platdata(dev);
> +
> +       setbits_le32(plat->base + GPIO_SWPORTA_DDR, 1 << pin);
> +
> +       if (val)
> +               setbits_le32(plat->base + GPIO_SWPORTA_DR, 1 << pin);
> +       else
> +               clrbits_le32(plat->base + GPIO_SWPORTA_DR, 1 << pin);
> +
> +       return 0;
> +}
> +
> +static int dwapb_gpio_get_value(struct udevice *dev, unsigned pin)
> +{
> +       struct gpio_dwapb_platdata *plat = dev_get_platdata(dev);
> +       return !!(readl(plat->base + GPIO_EXT_PORTA) & (1 << pin));
> +}
> +
> +
> +static int dwapb_gpio_set_value(struct udevice *dev, unsigned pin, int val)
> +{
> +       struct gpio_dwapb_platdata *plat = dev_get_platdata(dev);
> +
> +       if (val)
> +               setbits_le32(plat->base + GPIO_SWPORTA_DR, 1 << pin);
> +       else
> +               clrbits_le32(plat->base + GPIO_SWPORTA_DR, 1 << pin);
> +
> +       return 0;
> +}
> +
> +static const struct dm_gpio_ops gpio_dwapb_ops = {
> +       .direction_input        = dwapb_gpio_direction_input,
> +       .direction_output       = dwapb_gpio_direction_output,
> +       .get_value              = dwapb_gpio_get_value,
> +       .set_value              = dwapb_gpio_set_value,

Do you want to implement .function?

> +};
> +
> +static int gpio_dwapb_probe(struct udevice *dev)
> +{
> +       struct gpio_dev_priv *priv = dev_get_uclass_priv(dev);
> +       struct gpio_dwapb_platdata *plat = dev->platdata;
> +
> +       if (!plat)
> +               return 0;
> +
> +       priv->gpio_count = plat->pins;
> +       priv->bank_name = plat->name;
> +
> +       return 0;
> +}
> +
> +static int gpio_dwapb_bind(struct udevice *dev)
> +{
> +       struct gpio_dwapb_platdata *plat = dev_get_platdata(dev);
> +       const void *blob = gd->fdt_blob;
> +       struct udevice *subdev;
> +       fdt_addr_t base;
> +       int node, bank = 0;
> +       const char *name;
> +
> +       /* If this is a child device, there is nothing to do here */
> +       if (plat)
> +               return 0;
> +
> +       base = fdtdec_get_addr(blob, dev->of_offset, "reg");
> +       if (base == FDT_ADDR_T_NONE) {
> +               debug("Can't get the GPIO register base address\n");
> +               return -ENXIO;
> +       }
> +
> +       name = fdt_get_name(blob, dev->of_offset, NULL);
> +
> +       for (node = fdt_first_subnode(blob, dev->of_offset);
> +            node > 0;
> +            node = fdt_next_subnode(blob, node)) {
> +               int ret;
> +
> +               if (!fdtdec_get_bool(blob, node, "gpio-controller"))
> +                       continue;
> +
> +               plat = NULL;
> +               plat = calloc(1, sizeof(*plat));

I suppose this should use devm_alloc() now.

> +               if (!plat)
> +                       return -ENOMEM;
> +
> +               plat->base = base;
> +               plat->bank = bank;
> +               plat->pins = fdtdec_get_int(blob, node, "snps,nr-gpios", 0);
> +               snprintf(plat->name, sizeof(plat->name) - 1, "%s-bank%i-",
> +                        name, bank);

Why such a long name? That's going to be a pain to type in the 'gpio' command.

> +
> +               ret = device_bind(dev, dev->driver, plat->name,
> +                                 plat, -1, &subdev);
> +               if (ret)
> +                       return ret;
> +
> +               subdev->of_offset = node;
> +               bank++;
> +       }
> +
> +
> +       return 0;
> +}
> +
> +static const struct udevice_id gpio_dwapb_ids[] = {
> +       { .compatible = "snps,dw-apb-gpio" },
> +       { }
> +};
> +
> +U_BOOT_DRIVER(gpio_dwapb) = {
> +       .name           = "gpio-dwapb",
> +       .id             = UCLASS_GPIO,
> +       .of_match       = gpio_dwapb_ids,
> +       .ops            = &gpio_dwapb_ops,
> +       .bind           = gpio_dwapb_bind,
> +       .probe          = gpio_dwapb_probe,
> +};
> --
> 2.1.4
>

Regards,
Simon