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--- a/drivers/w1/masters/Kconfig
+++ b/drivers/w1/masters/Kconfig
@@ -42,5 +42,15 @@ config W1_MASTER_DS1WM
in HP iPAQ devices like h5xxx, h2200, and ASIC3-based like
hx4700.
+config W1_MASTER_GPIO
+ tristate "GPIO 1-wire busmaster"
+ depends on GENERIC_GPIO
+ help
+ Say Y here if you want to communicate with your 1-wire devices using
+ GPIO pins. This driver uses the GPIO API to control the wire.
+
+ This support is also available as a module. If so, the module
+ will be called w1-gpio.ko.
+
endmenu
--- a/drivers/w1/masters/Makefile
+++ b/drivers/w1/masters/Makefile
@@ -6,3 +6,4 @@ obj-$(CONFIG_W1_MASTER_MATROX) += matro
obj-$(CONFIG_W1_MASTER_DS2490) += ds2490.o
obj-$(CONFIG_W1_MASTER_DS2482) += ds2482.o
obj-$(CONFIG_W1_MASTER_DS1WM) += ds1wm.o
+obj-$(CONFIG_W1_MASTER_GPIO) += w1-gpio.o
--- /dev/null
+++ b/drivers/w1/masters/w1-gpio.c
@@ -0,0 +1,124 @@
+/*
+ * w1-gpio - GPIO w1 bus master driver
+ *
+ * Copyright (C) 2007 Ville Syrjala <syrjala@sci.fi>
+ *
+ * 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.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/w1-gpio.h>
+
+#include "../w1.h"
+#include "../w1_int.h"
+
+#include <asm/gpio.h>
+
+static void w1_gpio_write_bit_dir(void *data, u8 bit)
+{
+ struct w1_gpio_platform_data *pdata = data;
+
+ if (bit)
+ gpio_direction_input(pdata->pin);
+ else
+ gpio_direction_output(pdata->pin, 0);
+}
+
+static void w1_gpio_write_bit_val(void *data, u8 bit)
+{
+ struct w1_gpio_platform_data *pdata = data;
+
+ gpio_set_value(pdata->pin, bit);
+}
+
+static u8 w1_gpio_read_bit(void *data)
+{
+ struct w1_gpio_platform_data *pdata = data;
+
+ return gpio_get_value(pdata->pin);
+}
+
+static int __init w1_gpio_probe(struct platform_device *pdev)
+{
+ struct w1_bus_master *master;
+ struct w1_gpio_platform_data *pdata = pdev->dev.platform_data;
+ int err;
+
+ if (!pdata)
+ return -ENXIO;
+
+ master = kzalloc(sizeof(struct w1_bus_master), GFP_KERNEL);
+ if (!master)
+ return -ENOMEM;
+
+ err = gpio_request(pdata->pin, "w1");
+ if (err)
+ goto free_master;
+
+ master->data = pdata;
+ master->read_bit = w1_gpio_read_bit;
+
+ if (pdata->is_open_drain) {
+ gpio_direction_output(pdata->pin, 1);
+ master->write_bit = w1_gpio_write_bit_val;
+ } else {
+ gpio_direction_input(pdata->pin);
+ master->write_bit = w1_gpio_write_bit_dir;
+ }
+
+ err = w1_add_master_device(master);
+ if (err)
+ goto free_gpio;
+
+ platform_set_drvdata(pdev, master);
+
+ return 0;
+
+ free_gpio:
+ gpio_free(pdata->pin);
+ free_master:
+ kfree(master);
+
+ return err;
+}
+
+static int __exit w1_gpio_remove(struct platform_device *pdev)
+{
+ struct w1_bus_master *master = platform_get_drvdata(pdev);
+ struct w1_gpio_platform_data *pdata = pdev->dev.platform_data;
+
+ w1_remove_master_device(master);
+ gpio_free(pdata->pin);
+ kfree(master);
+
+ return 0;
+}
+
+static struct platform_driver w1_gpio_driver = {
+ .driver = {
+ .name = "w1-gpio",
+ .owner = THIS_MODULE,
+ },
+ .remove = __exit_p(w1_gpio_remove),
+};
+
+static int __init w1_gpio_init(void)
+{
+ return platform_driver_probe(&w1_gpio_driver, w1_gpio_probe);
+}
+
+static void __exit w1_gpio_exit(void)
+{
+ platform_driver_unregister(&w1_gpio_driver);
+}
+
+module_init(w1_gpio_init);
+module_exit(w1_gpio_exit);
+
+MODULE_DESCRIPTION("GPIO w1 bus master driver");
+MODULE_AUTHOR("Ville Syrjala <syrjala@sci.fi>");
+MODULE_LICENSE("GPL");
--- /dev/null
+++ b/include/linux/w1-gpio.h
@@ -0,0 +1,23 @@
+/*
+ * w1-gpio interface to platform code
+ *
+ * Copyright (C) 2007 Ville Syrjala <syrjala@sci.fi>
+ *
+ * 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.
+ */
+#ifndef _LINUX_W1_GPIO_H
+#define _LINUX_W1_GPIO_H
+
+/**
+ * struct w1_gpio_platform_data - Platform-dependent data for w1-gpio
+ * @pin: GPIO pin to use
+ * @is_open_drain: GPIO pin is configured as open drain
+ */
+struct w1_gpio_platform_data {
+ unsigned int pin;
+ unsigned int is_open_drain:1;
+};
+
+#endif /* _LINUX_W1_GPIO_H */
|
