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+=====================
+Kernel driver w1-gpio
+=====================
+
+Author: Ville Syrjala <syrjala@sci.fi>
+
+
+Description
+-----------
+
+GPIO 1-wire bus master driver. The driver uses the GPIO API to control the
+wire and the GPIO pin can be specified using GPIO machine descriptor tables.
+It is also possible to define the master using device tree, see
+Documentation/devicetree/bindings/w1/w1-gpio.yaml
+
+
+Example (mach-at91)
+-------------------
+
+::
+
+ #include <linux/gpio/machine.h>
+ #include <linux/w1-gpio.h>
+
+ static struct gpiod_lookup_table foo_w1_gpiod_table = {
+ .dev_id = "w1-gpio",
+ .table = {
+ GPIO_LOOKUP_IDX("at91-gpio", AT91_PIN_PB20, NULL, 0,
+ GPIO_ACTIVE_HIGH|GPIO_OPEN_DRAIN),
+ },
+ };
+
+ static struct w1_gpio_platform_data foo_w1_gpio_pdata = {
+ .ext_pullup_enable_pin = -EINVAL,
+ };
+
+ static struct platform_device foo_w1_device = {
+ .name = "w1-gpio",
+ .id = -1,
+ .dev.platform_data = &foo_w1_gpio_pdata,
+ };
+
+ ...
+ at91_set_GPIO_periph(foo_w1_gpio_pdata.pin, 1);
+ at91_set_multi_drive(foo_w1_gpio_pdata.pin, 1);
+ gpiod_add_lookup_table(&foo_w1_gpiod_table);
+ platform_device_register(&foo_w1_device);