[U-Boot] [PATCH] gpio: Add MT7621 GPIO support
Daniel Schwierzeck
daniel.schwierzeck at gmail.com
Sun Oct 7 18:23:30 UTC 2018
On 04.10.2018 13:39, Stefan Roese wrote:
> This patch adds GPIO support for the Mediatek MT7621 SoC, tested on
> MT7688 (Gardena smart-gateway). The driver is loosly based on the
> Linux kernel version.
>
> Signed-off-by: Stefan Roese <sr at denx.de>
> Cc: Daniel Schwierzeck <daniel.schwierzeck at gmail.com>
> ---
> drivers/gpio/Kconfig | 8 ++
> drivers/gpio/Makefile | 1 +
> drivers/gpio/mt7621_gpio.c | 212 +++++++++++++++++++++++++++++++++++++
> 3 files changed, 221 insertions(+)
> create mode 100644 drivers/gpio/mt7621_gpio.c
>
> diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
> index 5cd8b34400..35344e57c6 100644
> --- a/drivers/gpio/Kconfig
> +++ b/drivers/gpio/Kconfig
> @@ -314,4 +314,12 @@ config MPC8XXX_GPIO
> Aside from the standard functions of input/output mode, and output
> value setting, the open-drain feature, which can configure individual
> GPIOs to work as open-drain outputs, is supported.
> +
> +config MT7621_GPIO
> + bool "MediaTek MT7621 GPIO driver"
> + depends on DM_GPIO && ARCH_MT7620
> + default y
> + help
> + Say yes here to support MediaTek MT7621 compatible GPIOs.
> +
> endmenu
> diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
> index f186120684..7ed9a4ec42 100644
> --- a/drivers/gpio/Makefile
> +++ b/drivers/gpio/Makefile
> @@ -58,3 +58,4 @@ obj-$(CONFIG_MVEBU_GPIO) += mvebu_gpio.o
> obj-$(CONFIG_MSM_GPIO) += msm_gpio.o
> obj-$(CONFIG_$(SPL_)PCF8575_GPIO) += pcf8575_gpio.o
> obj-$(CONFIG_PM8916_GPIO) += pm8916_gpio.o
> +obj-$(CONFIG_MT7621_GPIO) += mt7621_gpio.o
> diff --git a/drivers/gpio/mt7621_gpio.c b/drivers/gpio/mt7621_gpio.c
> new file mode 100644
> index 0000000000..a467b21f2a
> --- /dev/null
> +++ b/drivers/gpio/mt7621_gpio.c
> @@ -0,0 +1,212 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Copyright (C) 2018 Stefan Roese <sr at denx.de>
> + *
> + * Based on the Linux driver version which is:
> + * Copyright (C) 2009-2011 Gabor Juhos <juhosg at openwrt.org>
> + * Copyright (C) 2013 John Crispin <blogic at openwrt.org>
> + */
> +
> +#include <common.h>
> +#include <dm.h>
> +#include <errno.h>
> +#include <fdtdec.h>
> +#include <malloc.h>
> +#include <linux/io.h>
> +#include <asm/io.h>
> +#include <asm/gpio.h>
> +#include <dm/device-internal.h>
> +#include <dt-bindings/gpio/gpio.h>
> +
> +#define MTK_MAX_BANK 3
> +#define MTK_BANK_WIDTH 32
> +
> +enum mediatek_gpio_reg {
> + GPIO_REG_CTRL = 0,
> + GPIO_REG_POL,
> + GPIO_REG_DATA,
> + GPIO_REG_DSET,
> + GPIO_REG_DCLR,
> + GPIO_REG_REDGE,
> + GPIO_REG_FEDGE,
> + GPIO_REG_HLVL,
> + GPIO_REG_LLVL,
> + GPIO_REG_STAT,
> + GPIO_REG_EDGE,
> +};
> +
> +static void __iomem *mediatek_gpio_membase;
> +
> +struct mediatek_gpio_platdata {
> + const char *bank_name; /* Name of bank, e.g. "B" */
> + int gpio_count;
> + int bank;
> +};
> +
> +static void mtk_gpio_w32(int bank, u8 reg, u32 val)
> +{
> + iowrite32(val, mediatek_gpio_membase + (reg * 0x10) + (bank * 0x4));
> +}
> +
> +static u32 mtk_gpio_r32(int bank, u8 reg)
> +{
> + return ioread32(mediatek_gpio_membase + (reg * 0x10) + (bank * 0x4));
> +}
> +
> +static int mediatek_gpio_get_value(struct udevice *dev, unsigned offset)
> +{
> + struct mediatek_gpio_platdata *plat = dev_get_platdata(dev);
> +
> + return !!(mtk_gpio_r32(plat->bank, GPIO_REG_DATA) & BIT(offset));
> +}
> +
> +static int mediatek_gpio_set_value(struct udevice *dev, unsigned offset,
> + int value)
> +{
> + struct mediatek_gpio_platdata *plat = dev_get_platdata(dev);
> +
> + mtk_gpio_w32(plat->bank, (value) ? GPIO_REG_DSET :
> + GPIO_REG_DCLR, BIT(offset));
> +
> + return 0;
> +}
> +
> +static int mediatek_gpio_direction_input(struct udevice *dev, unsigned offset)
> +{
> + struct mediatek_gpio_platdata *plat = dev_get_platdata(dev);
> + u32 t;
> +
> + t = mtk_gpio_r32(plat->bank, GPIO_REG_CTRL);
> + t &= ~BIT(offset);
> + mtk_gpio_w32(plat->bank, GPIO_REG_CTRL, t);
I would only wrap the "(reg * 0x10) + (bank * 0x4)" into a function and
directly use the I/O functions. Then you could also use clrbits, setbits
etc.
> +
> + return 0;
> +}
> +
> +static int mediatek_gpio_direction_output(struct udevice *dev, unsigned offset,
> + int value)
> +{
> + struct mediatek_gpio_platdata *plat = dev_get_platdata(dev);
> + u32 t;
> +
> + t = mtk_gpio_r32(plat->bank, GPIO_REG_CTRL);
> + t |= BIT(offset);
> + mtk_gpio_w32(plat->bank, GPIO_REG_CTRL, t);
> + mediatek_gpio_set_value(dev, offset, value);
> +
> + return 0;
> +}
> +
> +static int mediatek_gpio_get_function(struct udevice *dev, unsigned offset)
> +{
> + struct mediatek_gpio_platdata *plat = dev_get_platdata(dev);
> + u32 t;
> +
> + t = mtk_gpio_r32(plat->bank, GPIO_REG_CTRL);
> + if (t & BIT(offset))
> + return GPIOF_OUTPUT;
> +
> + return GPIOF_INPUT;
> +}
> +
> +static const struct dm_gpio_ops gpio_mediatek_ops = {
> + .direction_input = mediatek_gpio_direction_input,
> + .direction_output = mediatek_gpio_direction_output,
> + .get_value = mediatek_gpio_get_value,
> + .set_value = mediatek_gpio_set_value,
> + .get_function = mediatek_gpio_get_function,
> +};
> +
> +/**
> + * Returns the name of a GPIO bank
> + *
> + * GPIO banks are named A, B, C, ...
> + *
> + * @bank: Bank number (0, 1..n-1)
> + * @return allocated string containing the name
> + */
> +static char *gpio_bank_name(int bank)
> +{
> + char *name;
> +
> + name = malloc(3);
> + if (name) {
> + name[0] = 'P';
> + name[1] = 'A' + bank;
> + name[2] = '\0';
> + }
you could save this malloc() if you simply use "char bank_name[3]" in
plat_data and pass it to this function
> +
> + return name;
> +}
> +
> +static int gpio_mediatek_probe(struct udevice *dev)
> +{
> + struct mediatek_gpio_platdata *plat = dev_get_platdata(dev);
> + struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
> +
> + /* Tell the uclass how many GPIOs we have */
> + if (plat) {
> + uc_priv->gpio_count = plat->gpio_count;
> + uc_priv->bank_name = plat->bank_name;
> + }
> +
> + return 0;
> +}
> +
> +/**
> + * We have a top-level GPIO device with no actual GPIOs. It has a child
> + * device for each Mediatek bank.
> + */
> +static int gpio_mediatek_bind(struct udevice *parent)
> +{
> + struct mediatek_gpio_platdata *plat = parent->platdata;
> + const void *blob = gd->fdt_blob;
> + int node = dev_of_offset(parent);
> + int bank = 0;
> + int subnode;
> + int ret;
> +
> + /* If this is a child device, there is nothing to do here */
> + if (plat)
> + return 0;
> +
> + mediatek_gpio_membase = dev_remap_addr(parent);
> + if (!mediatek_gpio_membase)
> + return -EINVAL;
> +
> + fdt_for_each_subnode(subnode, blob, node) {
I think this loop can be rewritten with dev_read_first_subnode() and
dev_read_next_subnode() to be compatible with DM live tree
> + struct mediatek_gpio_platdata *plat;
> + struct udevice *dev;
> +
> + plat = calloc(1, sizeof(*plat));
> + if (!plat)
> + return -ENOMEM;
> + plat->bank_name = gpio_bank_name(bank);
> + plat->gpio_count = MTK_BANK_WIDTH;
> + plat->bank = bank;
> +
> + ret = device_bind(parent, parent->driver,
> + plat->bank_name, plat, -1, &dev);
> + if (ret)
> + return ret;
> +
> + dev_set_of_offset(dev, subnode);
> + bank++;
> + }
> +
> + return 0;
> +}
> +
> +static const struct udevice_id mediatek_gpio_ids[] = {
> + { .compatible = "mtk,mt7621-gpio" },
> + { }
> +};
> +
> +U_BOOT_DRIVER(gpio_mediatek) = {
> + .name = "gpio_mediatek",
> + .id = UCLASS_GPIO,
> + .ops = &gpio_mediatek_ops,
> + .of_match = mediatek_gpio_ids,
> + .bind = gpio_mediatek_bind,
> + .probe = gpio_mediatek_probe,
> +};
>
--
- Daniel
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 833 bytes
Desc: OpenPGP digital signature
URL: <http://lists.denx.de/pipermail/u-boot/attachments/20181007/273fd550/attachment.sig>
More information about the U-Boot
mailing list