From ad8dc96e3b2c3e28854e0de4ab49351ed547b30c Mon Sep 17 00:00:00 2001
From: Ville Syrjala <syrjala@sci.fi>
Date: Wed, 6 Feb 2008 01:39:01 -0800
Subject: w1-gpio: add GPIO w1 bus master driver

Add a GPIO 1-wire bus master driver.  The driver used the GPIO API to
control the wire and the GPIO pin can be specified using platform data
similar to i2c-gpio.  The driver was tested with AT91SAM9260 + DS2401.

Signed-off-by: Ville Syrjala <syrjala@sci.fi>
Cc: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
 Documentation/w1/masters/00-INDEX |  2 ++
 Documentation/w1/masters/w1-gpio  | 33 +++++++++++++++++++++++++++++++++
 2 files changed, 35 insertions(+)
 create mode 100644 Documentation/w1/masters/w1-gpio

(limited to 'Documentation/w1')

diff --git a/Documentation/w1/masters/00-INDEX b/Documentation/w1/masters/00-INDEX
index 752613c4cea..7b0ceaaad7a 100644
--- a/Documentation/w1/masters/00-INDEX
+++ b/Documentation/w1/masters/00-INDEX
@@ -4,3 +4,5 @@ ds2482
 	- The Maxim/Dallas Semiconductor DS2482 provides 1-wire busses.
 ds2490
 	- The Maxim/Dallas Semiconductor DS2490 builds USB <-> W1 bridges.
+w1-gpio
+	- GPIO 1-wire bus master driver.
diff --git a/Documentation/w1/masters/w1-gpio b/Documentation/w1/masters/w1-gpio
new file mode 100644
index 00000000000..af5d3b4aa85
--- /dev/null
+++ b/Documentation/w1/masters/w1-gpio
@@ -0,0 +1,33 @@
+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 platform data.
+
+
+Example (mach-at91)
+-------------------
+
+#include <linux/w1-gpio.h>
+
+static struct w1_gpio_platform_data foo_w1_gpio_pdata = {
+	.pin		= AT91_PIN_PB20,
+	.is_open_drain	= 1,
+};
+
+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);
+	platform_device_register(&foo_w1_device);
-- 
cgit v1.2.3-70-g09d2