[U-Boot] [PATCH] gpio: Add MT7621 GPIO support
Stefan Roese
sr at denx.de
Thu Oct 4 11:39:06 UTC 2018
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);
+
+ 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';
+ }
+
+ 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) {
+ 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,
+};
--
2.19.0
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