This patch adds driver to support GPIO functionality for 74xx-compatible
ICs with MMIO access. Compatible models include:
1 bit: 74AHC1G125 (Input), 74AUC1G74 (Output)
2 bits: 74LVC2G125 (Input), 74HC74 (Output)
4 bits: 74HC125 (Input), 74HC175 (Output)
6 bits: 74HC365 (Input), 74HC174 (Output)
8 bits: 74HC244 (Input), 74HC273 (Output)
16 bits: 74AC1624 (Input), 74AC16374 (Output)
Signed-off-by: Alexander Shiyan <shc_work@xxxxxxx>
---
drivers/gpio/Kconfig | 14 ++++
drivers/gpio/Makefile | 1 +
drivers/gpio/gpio-74xx-mmio.c | 170 ++++++++++++++++++++++++++++++++++++++++++
3 files changed, 185 insertions(+)
create mode 100644 drivers/gpio/gpio-74xx-mmio.c
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index ec398be..5397dfa6 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -112,6 +112,20 @@ config GPIO_MAX730X
comment "Memory mapped GPIO drivers:"
+config GPIO_74XX_MMIO
+ tristate "GPIO driver for 74xx-ICs with MMIO access"
+ depends on OF_GPIO
+ select GPIO_GENERIC
+ help
+ Say yes here to support GPIO functionality for 74xx-compatible ICs
+ with MMIO access. Compatible models include:
+ 1 bit:<---->74AHC1G125 (Input), 74AUC1G74 (Output)
+ 2 bits:<--->74LVC2G125 (Input), 74HC74 (Output)
+ 4 bits:<--->74HC125 (Input), 74HC175 (Output)
+ 6 bits:<--->74HC365 (Input), 74HC174 (Output)
+ 8 bits:<--->74HC244 (Input), 74HC273 (Output)
+ 16 bits:<-->74AC1624 (Input), 74AC16374 (Output)
+
config GPIO_CLPS711X
tristate "CLPS711X GPIO support"
depends on ARCH_CLPS711X || COMPILE_TEST
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index e5d346c..4486bbd 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -13,6 +13,7 @@ obj-$(CONFIG_GPIO_ACPI) += gpiolib-acpi.o
obj-$(CONFIG_GPIO_GENERIC) += gpio-generic.o
obj-$(CONFIG_GPIO_74X164) += gpio-74x164.o
+obj-$(CONFIG_GPIO_74XX_MMIO) += gpio-74xx-mmio.o
obj-$(CONFIG_GPIO_ADNP) += gpio-adnp.o
obj-$(CONFIG_GPIO_ADP5520) += gpio-adp5520.o
obj-$(CONFIG_GPIO_ADP5588) += gpio-adp5588.o
diff --git a/drivers/gpio/gpio-74xx-mmio.c b/drivers/gpio/gpio-74xx-mmio.c
new file mode 100644
index 0000000..6efa7ed
--- /dev/null
+++ b/drivers/gpio/gpio-74xx-mmio.c
@@ -0,0 +1,170 @@
+/*
+ * 74xx MMIO GPIO driver
+ *
+ * Copyright (C) 2014 Alexander Shiyan <shc_work@xxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/err.h>
+#include <linux/gpio.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/basic_mmio_gpio.h>
+#include <linux/platform_device.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 flags;
+};
+
+static const struct of_device_id mmio_74xx_gpio_ids[] = {
+ {
+ .compatible = "ti,74ahc1g125",
+ .data = (const void *)(MMIO_74XX_DIR_IN | 1),
+ },
+ {
+ .compatible = "ti,74lvc2g125",
+ .data = (const void *)(MMIO_74XX_DIR_IN | 2),
+ },
+ {
+ .compatible = "ti,74hc125",
+ .data = (const void *)(MMIO_74XX_DIR_IN | 4),
+ },
+ {
+ .compatible = "ti,74hc365",
+ .data = (const void *)(MMIO_74XX_DIR_IN | 6),
+ },
+ {
+ .compatible = "ti,74hc244",
+ .data = (const void *)(MMIO_74XX_DIR_IN | 8),
+ },
+ {
+ .compatible = "ti,74ac1624",
+ .data = (const void *)(MMIO_74XX_DIR_IN | 16),
+ },
+ {
+ .compatible = "ti,74auc1g74",
+ .data = (const void *)(MMIO_74XX_DIR_OUT | 1),
+ },
+ {
+ .compatible = "ti,74hc74",
+ .data = (const void *)(MMIO_74XX_DIR_OUT | 2),
+ },
+ {
+ .compatible = "ti,74hc175",
+ .data = (const void *)(MMIO_74XX_DIR_OUT | 4),
+ },
+ {
+ .compatible = "ti,74hc174",
+ .data = (const void *)(MMIO_74XX_DIR_OUT | 6),
+ },
+ {
+ .compatible = "ti,74hc273",
+ .data = (const void *)(MMIO_74XX_DIR_OUT | 8),
+ },
+ {
+ .compatible = "ti,74ac16374",
+ .data = (const void *)(MMIO_74XX_DIR_OUT | 16),
+ },
+ { }
+};
+MODULE_DEVICE_TABLE(of, mmio_74xx_gpio_ids);
+
+static inline struct mmio_74xx_gpio_priv *to_74xx_gpio(struct gpio_chip *gc)
+{
+ struct bgpio_chip *bgc = to_bgpio_chip(gc);
+
+ return container_of(bgc, struct mmio_74xx_gpio_priv, bgc);
+}
+
+static int mmio_74xx_get_direction(struct gpio_chip *gc, unsigned offset)
+{
+ struct mmio_74xx_gpio_priv *priv = to_74xx_gpio(gc);
+
+ return (priv->flags & MMIO_74XX_DIR_OUT) ? GPIOF_DIR_OUT : GPIOF_DIR_IN;
+}
+
+static int mmio_74xx_dir_in(struct gpio_chip *gc, unsigned int gpio)
+{
+ struct mmio_74xx_gpio_priv *priv = to_74xx_gpio(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_74xx_gpio(gc);
+
+ if (priv->flags & MMIO_74XX_DIR_OUT) {
+ gc->set(gc, gpio, val);
+ return 0;
+ }
+
+ return -ENOTSUPP;
+}
+
+static int mmio_74xx_gpio_probe(struct platform_device *pdev)
+{
+ const struct of_device_id *of_id =
+ of_match_device(mmio_74xx_gpio_ids, &pdev->dev);
+ struct mmio_74xx_gpio_priv *priv;
+ struct resource *res;
+ void __iomem *dat;
+ int err;
+
+ priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ dat = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(dat))
+ return PTR_ERR(dat);
+
+ priv->flags = (unsigned)of_id->data;
+
+ err = bgpio_init(&priv->bgc, &pdev->dev,
+ DIV_ROUND_UP(MMIO_74XX_BIT_CNT(priv->flags), 8),
+ dat, NULL, NULL, NULL, NULL, 0);
+ if (err)
+ return err;
+
+ priv->bgc.gc.direction_input = mmio_74xx_dir_in;
+ priv->bgc.gc.direction_output = mmio_74xx_dir_out;
+ priv->bgc.gc.get_direction = mmio_74xx_get_direction;
+ priv->bgc.gc.ngpio = MMIO_74XX_BIT_CNT(priv->flags);
+ priv->bgc.gc.owner = THIS_MODULE;
+
+ platform_set_drvdata(pdev, priv);
+
+ return gpiochip_add(&priv->bgc.gc);
+}
+
+static int mmio_74xx_gpio_remove(struct platform_device *pdev)
+{
+ struct mmio_74xx_gpio_priv *priv = platform_get_drvdata(pdev);
+
+ return bgpio_remove(&priv->bgc);
+}
+
+static struct platform_driver mmio_74xx_gpio_driver = {
+ .driver = {
+ .name = "74xx-mmio-gpio",
+ .of_match_table = mmio_74xx_gpio_ids,
+ },
+ .probe = mmio_74xx_gpio_probe,
+ .remove = mmio_74xx_gpio_remove,
+};
+module_platform_driver(mmio_74xx_gpio_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Alexander Shiyan <shc_work@xxxxxxx>");
+MODULE_DESCRIPTION("74xx MMIO GPIO driver");
--
1.8.5.5
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