[PATCH 4/9] gpio: add driver for 74xx-ICs with MMIO access
Antony Pavlov
antonynpavlov at gmail.com
Wed May 5 03:08:55 PDT 2021
This patch adds driver to support GPIO functionality
for 74xx-compatible ICs with MMIO access.
Compatible models include:
1 bit: 741G125 (Input), 741G74 (Output)
2 bits: 742G125 (Input), 7474 (Output)
4 bits: 74125 (Input), 74175 (Output)
6 bits: 74365 (Input), 74174 (Output)
8 bits: 74244 (Input), 74273 (Output)
16 bits: 741624 (Input), 7416374 (Output)
Signed-off-by: Antony Pavlov <antonynpavlov at gmail.com>
Cc: Alexander Shiyan <shc_work at mail.ru>
---
drivers/gpio/Kconfig | 14 +++
drivers/gpio/Makefile | 1 +
drivers/gpio/gpio-74xx-mmio.c | 170 ++++++++++++++++++++++++++++++++++
3 files changed, 185 insertions(+)
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 261b6e6662..59cb00ff22 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -21,6 +21,20 @@ config GPIO_74164
shift registers. This driver can be used to provide access
to more gpio outputs.
+config GPIO_74XX_MMIO
+ tristate "GPIO driver for 74xx-ICs with MMIO access"
+ depends on OFDEVICE
+ select GPIO_GENERIC
+ help
+ Say yes here to support GPIO functionality for 74xx-compatible ICs
+ with MMIO access. Compatible models include:
+ 1 bit: 741G125 (Input), 741G74 (Output)
+ 2 bits: 742G125 (Input), 7474 (Output)
+ 4 bits: 74125 (Input), 74175 (Output)
+ 6 bits: 74365 (Input), 74174 (Output)
+ 8 bits: 74244 (Input), 74273 (Output)
+ 16 bits: 741624 (Input), 7416374 (Output)
+
config GPIO_CLPS711X
bool "GPIO support for CLPS711X"
depends on ARCH_CLPS711X || COMPILE_TEST
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 77dcf58f64..7ece8621d2 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -1,6 +1,7 @@
obj-$(CONFIG_GPIOLIB) += gpiolib.o
obj-$(CONFIG_GPIO_74164) += gpio-74164.o
+obj-$(CONFIG_GPIO_74XX_MMIO) += gpio-74xx-mmio.o
obj-$(CONFIG_MACH_MIPS_ATH79) += gpio-ath79.o
obj-$(CONFIG_GPIO_DAVINCI) += gpio-davinci.o
obj-$(CONFIG_GPIO_CLPS711X) += gpio-clps711x.o
diff --git a/drivers/gpio/gpio-74xx-mmio.c b/drivers/gpio/gpio-74xx-mmio.c
new file mode 100644
index 0000000000..2c05d022f1
--- /dev/null
+++ b/drivers/gpio/gpio-74xx-mmio.c
@@ -0,0 +1,170 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * 74xx MMIO GPIO driver
+ *
+ * Copyright (C) 2014 Alexander Shiyan <shc_work at mail.ru>
+ *
+ * Ported to barebox from linux-v5.4-rc6
+ * Copyright (C) 2019-2021 Antony Pavlov <antonynpavlov at gmail.com>
+ *
+ */
+
+#include <common.h>
+#include <driver.h>
+#include <errno.h>
+#include <gpio.h>
+#include <init.h>
+#include <io.h>
+#include <malloc.h>
+
+#include <linux/err.h>
+#include <linux/basic_mmio_gpio.h>
+
+#define MMIO_74XX_DIR_IN (0 << 8)
+#define MMIO_74XX_DIR_OUT (1 << 8)
+#define MMIO_74XX_BIT_CNT(x) ((x) & 0xff)
+
+struct mmio_74xx_gpio_priv {
+ struct bgpio_chip bgc;
+ unsigned int flags;
+};
+
+static const struct of_device_id mmio_74xx_gpio_ids[] = {
+ {
+ .compatible = "ti,741g125",
+ .data = (const void *)(MMIO_74XX_DIR_IN | 1),
+ },
+ {
+ .compatible = "ti,742g125",
+ .data = (const void *)(MMIO_74XX_DIR_IN | 2),
+ },
+ {
+ .compatible = "ti,74125",
+ .data = (const void *)(MMIO_74XX_DIR_IN | 4),
+ },
+ {
+ .compatible = "ti,74365",
+ .data = (const void *)(MMIO_74XX_DIR_IN | 6),
+ },
+ {
+ .compatible = "ti,74244",
+ .data = (const void *)(MMIO_74XX_DIR_IN | 8),
+ },
+ {
+ .compatible = "ti,741624",
+ .data = (const void *)(MMIO_74XX_DIR_IN | 16),
+ },
+ {
+ .compatible = "ti,741g74",
+ .data = (const void *)(MMIO_74XX_DIR_OUT | 1),
+ },
+ {
+ .compatible = "ti,7474",
+ .data = (const void *)(MMIO_74XX_DIR_OUT | 2),
+ },
+ {
+ .compatible = "ti,74175",
+ .data = (const void *)(MMIO_74XX_DIR_OUT | 4),
+ },
+ {
+ .compatible = "ti,74174",
+ .data = (const void *)(MMIO_74XX_DIR_OUT | 6),
+ },
+ {
+ .compatible = "ti,74273",
+ .data = (const void *)(MMIO_74XX_DIR_OUT | 8),
+ },
+ {
+ .compatible = "ti,7416374",
+ .data = (const void *)(MMIO_74XX_DIR_OUT | 16),
+ },
+ { }
+};
+
+static inline
+struct mmio_74xx_gpio_priv *to_mmio_74xx_gpio_priv(struct gpio_chip *gc)
+{
+ struct bgpio_chip *bgc =
+ container_of(gc, struct bgpio_chip, gc);
+
+ return container_of(bgc, struct mmio_74xx_gpio_priv, bgc);
+}
+
+static int mmio_74xx_get_direction(struct gpio_chip *gc, unsigned int offset)
+{
+ struct mmio_74xx_gpio_priv *priv = to_mmio_74xx_gpio_priv(gc);
+
+ if (priv->flags & MMIO_74XX_DIR_OUT)
+ return GPIOF_DIR_OUT;
+
+ return GPIOF_DIR_IN;
+}
+
+static int mmio_74xx_dir_in(struct gpio_chip *gc, unsigned int gpio)
+{
+ struct mmio_74xx_gpio_priv *priv = to_mmio_74xx_gpio_priv(gc);
+
+ return (priv->flags & MMIO_74XX_DIR_OUT) ? -ENOTSUPP : 0;
+}
+
+static int mmio_74xx_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
+{
+ struct mmio_74xx_gpio_priv *priv = to_mmio_74xx_gpio_priv(gc);
+
+ if (priv->flags & MMIO_74XX_DIR_OUT) {
+ gc->ops->set(gc, gpio, val);
+ return 0;
+ }
+
+ return -ENOTSUPP;
+}
+
+static int mmio_74xx_gpio_probe(struct device_d *dev)
+{
+ struct mmio_74xx_gpio_priv *priv;
+ void __iomem *dat;
+ int err;
+ struct gpio_chip *gc;
+
+ priv = xzalloc(sizeof(*priv));
+
+ err = dev_get_drvdata(dev, (const void **)&priv->flags);
+ if (err)
+ return err;
+
+ dat = dev_request_mem_region(dev, 0);
+ if (IS_ERR(dat))
+ return PTR_ERR(dat);
+
+ err = bgpio_init(&priv->bgc, dev,
+ DIV_ROUND_UP(MMIO_74XX_BIT_CNT(priv->flags), 8),
+ dat, NULL, NULL, NULL, NULL, 0);
+ if (err)
+ return err;
+
+ gc = &priv->bgc.gc;
+ gc->ops->direction_input = mmio_74xx_dir_in;
+ gc->ops->direction_output = mmio_74xx_dir_out;
+ gc->ops->get_direction = mmio_74xx_get_direction;
+ gc->ngpio = MMIO_74XX_BIT_CNT(priv->flags);
+
+ dev->priv = priv;
+
+ return gpiochip_add(gc);
+}
+
+static struct driver_d mmio_74xx_gpio_driver = {
+ .name = "74xx-mmio-gpio",
+ .of_compatible = DRV_OF_COMPAT(mmio_74xx_gpio_ids),
+ .probe = mmio_74xx_gpio_probe,
+};
+
+static int mmio_74xx_gpio_init(void)
+{
+ return platform_driver_register(&mmio_74xx_gpio_driver);
+}
+coredevice_initcall(mmio_74xx_gpio_init);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Alexander Shiyan <shc_work at mail.ru>");
+MODULE_DESCRIPTION("74xx MMIO GPIO driver");
--
2.31.1
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