On 31.07.2012 02:59, Ville Syrjälä wrote:
> On Mon, Jul 30, 2012 at 10:12:39PM +0400, Evgeniy Polyakov wrote:
>> Hi
>>
>> Sorry for long delay
>> [resend with fixed Greg's address :)]
>>
>> On Wed, Jul 25, 2012 at 10:54:29PM +0200, Daniel Mack (zon...@gmail.com)
>> wrote:
>>> In the process of porting boards to devicetree implemenation, we should
>>> keep information about external circuitry where they belong - the
>>> individual drivers.
>>>
>>> This patch adds a way to specify a GPIO to drive the (optional) external
>>> pull-up logic, rather than using a function pointer for that.
>>
>> I do not object against this patch, but I have rather limited knowledge
>> about gpio driver. Patch looks good, feel free to add my
>> Acked-by: Evgeniy Polyakov <z...@ioremap.net>
>>
>> Greg, please pull it into your tree, if Ville does not object.
>
> No objections from me.
I take this as an Acked-by:?
> The only cosmetic issue I spotted was 'pdata' being assigned twice in
> w1_gpio_probe().
Right. Amended patch below.
Thanks a lot,
Daniel
>From 37385d15bbd9dbc637f1e46d962c90be5eeb1409 Mon Sep 17 00:00:00 2001
From: Daniel Mack <zon...@gmail.com>
Date: Mon, 23 Jul 2012 16:36:35 +0200
Subject: [PATCH v2] onewire: w1-gpio: add DT bindings
This patch add DT bindings to the w1-gpio driver, along with some
documentation on how to use them.
Signed-off-by: Daniel Mack <zon...@gmail.com>
Acked-by: Evgeniy Polyakov <z...@ioremap.net>
Acked-by: Ville Syrjala <syrj...@sci.fi>
---
Documentation/devicetree/bindings/w1/w1-gpio.txt | 22 +++++++++++
drivers/w1/masters/w1-gpio.c | 48 +++++++++++++++++++++++-
2 files changed, 69 insertions(+), 1 deletion(-)
create mode 100644 Documentation/devicetree/bindings/w1/w1-gpio.txt
diff --git a/Documentation/devicetree/bindings/w1/w1-gpio.txt b/Documentation/devicetree/bindings/w1/w1-gpio.txt
new file mode 100644
index 0000000..6e09c35
--- /dev/null
+++ b/Documentation/devicetree/bindings/w1/w1-gpio.txt
@@ -0,0 +1,22 @@
+w1-gpio devicetree bindings
+
+Required properties:
+
+ - compatible: "w1-gpio"
+ - gpios: one or two GPIO specs:
+ - the first one is used as data I/O pin
+ - the second one is optional. If specified, it is used as
+ enable pin for an external pin pullup.
+
+Optional properties:
+
+ - linux,open-drain: if specified, the data pin is considered in
+ open-drain mode.
+
+Examples:
+
+ onewire@0 {
+ compatible = "w1-gpio";
+ gpios = <&gpio 126 0>, <&gpio 105 0>;
+ };
+
diff --git a/drivers/w1/masters/w1-gpio.c b/drivers/w1/masters/w1-gpio.c
index dac88ff..6012c4e 100644
--- a/drivers/w1/masters/w1-gpio.c
+++ b/drivers/w1/masters/w1-gpio.c
@@ -14,6 +14,8 @@
#include <linux/slab.h>
#include <linux/w1-gpio.h>
#include <linux/gpio.h>
+#include <linux/of_platform.h>
+#include <linux/of_gpio.h>
#include "../w1.h"
#include "../w1_int.h"
@@ -42,12 +44,55 @@ static u8 w1_gpio_read_bit(void *data)
return gpio_get_value(pdata->pin) ? 1 : 0;
}
+#ifdef CONFIG_OF
+static struct of_device_id w1_gpio_dt_ids[] = {
+ { .compatible = "w1-gpio" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, w1_gpio_dt_ids);
+
+static int w1_gpio_probe_dt(struct platform_device *pdev)
+{
+ struct w1_gpio_platform_data *pdata = pdev->dev.platform_data;
+ struct device_node *np = pdev->dev.of_node;
+ const struct of_device_id *of_id =
+ of_match_device(w1_gpio_dt_ids, &pdev->dev);
+
+ if (!of_id)
+ return 0;
+
+ pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
+ if (!pdata)
+ return -ENOMEM;
+
+ if (of_get_property(np, "linux,open-drain", NULL))
+ pdata->is_open_drain = 1;
+
+ pdata->pin = of_get_gpio(np, 0);
+ pdata->ext_pullup_enable_pin = of_get_gpio(np, 1);
+ pdev->dev.platform_data = pdata;
+
+ return 0;
+}
+#else
+static int w1_gpio_probe_dt(struct platform_device *pdev)
+{
+ return 0;
+}
+#endif
+
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;
+ struct w1_gpio_platform_data *pdata;
int err;
+ err = w1_gpio_probe_dt(pdev);
+ if (err < 0)
+ return err;
+
+ pdata = pdev->dev.platform_data;
+
if (!pdata)
return -ENXIO;
@@ -151,6 +196,7 @@ static struct platform_driver w1_gpio_driver = {
.driver = {
.name = "w1-gpio",
.owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(w1_gpio_dt_ids),
},
.remove = __exit_p(w1_gpio_remove),
.suspend = w1_gpio_suspend,
--
1.7.11.2
