The ACCES 104-IDIO-16 family of PC/104 utility boards feature 16
optically isolated inputs and 16 optically isolated FET solid state
outputs. This driver provides GPIO support for these 32 channels of
digital I/O. Change-of-State detection interrupts are not supported.
GPIO 0-15 correspond to digital outputs 0-15, while GPIO 16-31
correspond to digital inputs 0-15. The base port address for the device
may be set via the a_104_idio_16_base module parameter.
Signed-off-by: William Breathitt Gray <vilhelm.g...@gmail.com>
---
Changes in v7:
- Return -EINVAL when gpio_get operation is requested for output-only
pins
- Conform chip label string to platform device/driver name string
- Unregister platform device on platform driver registration failure
drivers/gpio/Kconfig | 10 ++
drivers/gpio/Makefile | 1 +
drivers/gpio/gpio-104-idio-16.c | 217 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 228 insertions(+)
create mode 100644 drivers/gpio/gpio-104-idio-16.c
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 8949b3f..dc843e0 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -684,6 +684,16 @@ config GPIO_SX150X
endmenu
+menu "ISA GPIO drivers"
+
+config GPIO_104_IDIO_16
+ tristate "ACCES 104-IDIO-16 GPIO support"
+ depends on X86
+ help
+ Enables GPIO support for the ACCES 104-IDIO-16 family.
+
+endmenu
+
menu "MFD GPIO expanders"
config GPIO_ADP5520
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index f79a7c4..6f2fea5 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -12,6 +12,7 @@ obj-$(CONFIG_GPIO_ACPI) += gpiolib-acpi.o
# Device drivers. Generally keep list sorted alphabetically
obj-$(CONFIG_GPIO_GENERIC) += gpio-generic.o
+obj-$(CONFIG_GPIO_104_IDIO_16) += gpio-104-idio-16.o
obj-$(CONFIG_GPIO_74X164) += gpio-74x164.o
obj-$(CONFIG_GPIO_74XX_MMIO) += gpio-74xx-mmio.o
obj-$(CONFIG_GPIO_ADNP) += gpio-adnp.o
diff --git a/drivers/gpio/gpio-104-idio-16.c b/drivers/gpio/gpio-104-idio-16.c
new file mode 100644
index 0000000..df7f395
--- /dev/null
+++ b/drivers/gpio/gpio-104-idio-16.c
@@ -0,0 +1,217 @@
+/*
+ * GPIO driver for the ACCES 104-IDIO-16 family
+ * Copyright (C) 2015 William Breathitt Gray
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ */
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/gpio/driver.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/platform_device.h>
+#include <linux/spinlock.h>
+
+static unsigned a_104_idio_16_base;
+module_param(a_104_idio_16_base, uint, 0);
+MODULE_PARM_DESC(a_104_idio_16_base, "ACCES 104-IDIO-16 base address");
+
+/**
+ * struct a_104_idio_16_gpio - GPIO device private data structure
+ * @chip: instance of the gpio_chip
+ * @lock: synchronization lock to prevent gpio_set race conditions
+ * @base: base port address of the GPIO device
+ * @extent: extent of port address region of the GPIO device
+ * @out_state: output bits state
+ */
+struct a_104_idio_16_gpio {
+ struct gpio_chip chip;
+ spinlock_t lock;
+ unsigned base;
+ unsigned extent;
+ unsigned out_state;
+};
+
+static int a_104_idio_16_gpio_get_direction(struct gpio_chip *chip,
+ unsigned offset)
+{
+ if (offset > 15)
+ return 1;
+
+ return 0;
+}
+
+static int a_104_idio_16_gpio_direction_input(struct gpio_chip *chip,
+ unsigned offset)
+{
+ return 0;
+}
+
+static int a_104_idio_16_gpio_direction_output(struct gpio_chip *chip,
+ unsigned offset, int value)
+{
+ chip->set(chip, offset, value);
+ return 0;
+}
+
+static struct a_104_idio_16_gpio *to_a104idio16gp(struct gpio_chip *gc)
+{
+ return container_of(gc, struct a_104_idio_16_gpio, chip);
+}
+
+static int a_104_idio_16_gpio_get(struct gpio_chip *chip, unsigned offset)
+{
+ struct a_104_idio_16_gpio *const a104idio16gp = to_a104idio16gp(chip);
+ const unsigned BIT_MASK = 1U << (offset-16);
+
+ if (offset < 16)
+ return -EINVAL;
+
+ if (offset < 24)
+ return !!(inb(a104idio16gp->base + 1) & BIT_MASK);
+
+ return !!(inb(a104idio16gp->base + 5) & (BIT_MASK>>8));
+}
+
+static void a_104_idio_16_gpio_set(struct gpio_chip *chip, unsigned offset,
+ int value)
+{
+ struct a_104_idio_16_gpio *const a104idio16gp = to_a104idio16gp(chip);
+ const unsigned BIT_MASK = 1U << offset;
+ unsigned long flags;
+
+ if (offset > 15)
+ return;
+
+ spin_lock_irqsave(&a104idio16gp->lock, flags);
+
+ if (value)
+ a104idio16gp->out_state |= BIT_MASK;
+ else
+ a104idio16gp->out_state &= ~BIT_MASK;
+
+ if (offset > 7)
+ outb(~a104idio16gp->out_state >> 8, a104idio16gp->base + 4);
+ else
+ outb(~a104idio16gp->out_state, a104idio16gp->base);
+
+ spin_unlock_irqrestore(&a104idio16gp->lock, flags);
+}
+
+static int __init a_104_idio_16_probe(struct platform_device *pdev)
+{
+ struct a_104_idio_16_gpio *const a104idio16gp = pdev->dev.platform_data;
+ struct device *dev = &pdev->dev;
+ int err;
+
+ const unsigned BASE = a104idio16gp->base;
+ const unsigned EXTENT = a104idio16gp->extent;
+
+ if (!request_region(BASE, EXTENT, "104-idio-16")) {
+ dev_err(dev, "Unable to lock 104-idio-16 port addresses
(0x%X-0x%X)\n",
+ BASE, BASE + EXTENT);
+ err = -EBUSY;
+ goto out_lock_a_104_idio_16_port;
+ }
+
+ spin_lock_init(&a104idio16gp->lock);
+
+ dev_info(dev, "104-IDIO-16 GPIO detected\n");
+ err = gpiochip_add(&a104idio16gp->chip);
+ if (err) {
+ dev_err(dev, "GPIO registering failed (%d)\n", err);
+ goto out_gpio_register;
+ }
+
+ return 0;
+
+out_gpio_register:
+ release_region(BASE, EXTENT);
+out_lock_a_104_idio_16_port:
+ return err;
+}
+
+static int a_104_idio_16_remove(struct platform_device *pdev)
+{
+ struct a_104_idio_16_gpio *const a104idio16gp = pdev->dev.platform_data;
+
+ gpiochip_remove(&a104idio16gp->chip);
+ release_region(a104idio16gp->base, a104idio16gp->extent);
+
+ return 0;
+}
+
+static struct platform_device *a_104_idio_16_device;
+
+static struct platform_driver a_104_idio_16_driver = {
+ .driver = {
+ .name = "104-idio-16",
+ },
+ .remove = a_104_idio_16_remove
+};
+
+static void __exit a_104_idio_16_exit(void)
+{
+ dev_info(&a_104_idio_16_device->dev, "Exiting module\n");
+
+ platform_device_unregister(a_104_idio_16_device);
+ platform_driver_unregister(&a_104_idio_16_driver);
+}
+
+static int __init a_104_idio_16_init(void)
+{
+ int err;
+ struct a_104_idio_16_gpio a104idio16gp = {
+ .chip = {
+ .label = "104-idio-16",
+ .owner = THIS_MODULE,
+ .base = -1,
+ .ngpio = 32,
+ .get_direction = a_104_idio_16_gpio_get_direction,
+ .direction_input = a_104_idio_16_gpio_direction_input,
+ .direction_output = a_104_idio_16_gpio_direction_output,
+ .get = a_104_idio_16_gpio_get,
+ .set = a_104_idio_16_gpio_set
+ },
+ .base = a_104_idio_16_base,
+ .extent = 8
+ };
+
+ a_104_idio_16_device = platform_device_register_data(NULL,
+ "104-idio-16", -1, &a104idio16gp, sizeof(a104idio16gp));
+ if (IS_ERR(a_104_idio_16_device)) {
+ err = PTR_ERR(a_104_idio_16_device);
+ goto out_platform_device;
+ }
+
+ dev_info(&a_104_idio_16_device->dev, "Initializing module\n");
+
+ err = platform_driver_probe(&a_104_idio_16_driver, a_104_idio_16_probe);
+ if (err)
+ goto out_platform_driver;
+
+ return 0;
+
+out_platform_driver:
+ platform_device_unregister(a_104_idio_16_device);
+out_platform_device:
+ return err;
+}
+
+module_init(a_104_idio_16_init);
+module_exit(a_104_idio_16_exit);
+
+MODULE_AUTHOR("William Breathitt Gray <vilhelm.g...@gmail.com>");
+MODULE_DESCRIPTION("ACCES 104-IDIO-16 GPIO driver");
+MODULE_LICENSE("GPL");
--
2.4.9
--
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