[PATCH v2] iio: inkern: Add of_xlate function to struct iio_info

[PATCH v2] iio: inkern: Add of_xlate function to struct iio_info

[Ivan T. Ivanov]

When #iio-cells is greater than '0', the driver could provide
a custom of_xlate function that reads the *args* and returns
the appropriate index in registered IIO channels array.

Add simple translation function, suitable for the most 1:1
mapped channels in IIO chips, and use it when driver did not
provide custom implementation.

Signed-off-by: Ivan T. Ivanov <iivanov@mm-sol.com>
---

Changes:
- Move of_xlate function from iio_dev to iio_info structure,
  where all the other callbacks are. 

 drivers/iio/inkern.c    | 33 ++++++++++++++++++++++++++++-----
 include/linux/iio/iio.h |  8 ++++++++
 2 files changed, 36 insertions(+), 5 deletions(-)

diff --git a/drivers/iio/inkern.c b/drivers/iio/inkern.c
index f084610..866fe90 100644
--- a/drivers/iio/inkern.c
+++ b/drivers/iio/inkern.c
@@ -100,6 +100,28 @@ static int iio_dev_node_match(struct device *dev, void *data)
 	return dev->of_node == data && dev->type == &iio_device_type;
 }
 
+/**
+ * __of_iio_simple_xlate - translate iiospec to the IIO channel index
+ * @indio_dev:	pointer to the iio_dev structure
+ * @iiospec:	IIO specifier as found in the device tree
+ *
+ * This is simple translation function, suitable for the most 1:1 mapped
+ * channels in IIO chips. This function performs only one sanity check:
+ * whether IIO index is less than num_channels (that is specified in the
+ * iio_dev).
+ */
+static int __of_iio_simple_xlate(struct iio_dev *indio_dev,
+				const struct of_phandle_args *iiospec)
+{
+	if (!iiospec->args_count)
+		return 0;
+
+	if (iiospec->args[0] >= indio_dev->num_channels)
+		return -EINVAL;
+
+	return iiospec->args[0];
+}
+
 static int __of_iio_channel_get(struct iio_channel *channel,
 				struct device_node *np, int index)
 {
@@ -122,18 +144,19 @@ static int __of_iio_channel_get(struct iio_channel *channel,
 
 	indio_dev = dev_to_iio_dev(idev);
 	channel->indio_dev = indio_dev;
-	index = iiospec.args_count ? iiospec.args[0] : 0;
-	if (index >= indio_dev->num_channels) {
-		err = -EINVAL;
+	if (indio_dev->info->of_xlate)
+		index = indio_dev->info->of_xlate(indio_dev, &iiospec);
+	else
+		index = __of_iio_simple_xlate(indio_dev, &iiospec);
+	if (index < 0)
 		goto err_put;
-	}
 	channel->channel = &indio_dev->channels[index];
 
 	return 0;
 
 err_put:
 	iio_device_put(indio_dev);
-	return err;
+	return index;
 }
 
 static struct iio_channel *of_iio_channel_get(struct device_node *np, int index)
diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h
index 15dc6bc..3642ce7 100644
--- a/include/linux/iio/iio.h
+++ b/include/linux/iio/iio.h
@@ -13,6 +13,7 @@
 #include <linux/device.h>
 #include <linux/cdev.h>
 #include <linux/iio/types.h>
+#include <linux/of.h>
 /* IIO TODO LIST */
 /*
  * Provide means of adjusting timer accuracy.
@@ -326,6 +327,11 @@ struct iio_dev;
  * @update_scan_mode:	function to configure device and scan buffer when
  *			channels have changed
  * @debugfs_reg_access:	function to read or write register value of device
+ * @of_xlate:		function pointer to obtain channel specifier index.
+ *			When #iio-cells is greater than '0', the driver could
+ *			provide a custom of_xlate function that reads the
+ *			*args* and returns the appropriate index in registered
+ *			IIO channels array.
  **/
 struct iio_info {
 	struct module			*driver_module;
@@ -385,6 +391,8 @@ struct iio_info {
 	int (*debugfs_reg_access)(struct iio_dev *indio_dev,
 				  unsigned reg, unsigned writeval,
 				  unsigned *readval);
+	int (*of_xlate)(struct iio_dev *indio_dev,
+			const struct of_phandle_args *iiospec);
 };
 
 /**
-- 
1.9.1

Re: [PATCH v2] iio: inkern: Add of_xlate function to struct iio_info

[Lars-Peter Clausen]

On 10/22/2014 05:29 PM, Ivan T. Ivanov wrote:
> When #iio-cells is greater than '0', the driver could provide
> a custom of_xlate function that reads the *args* and returns
> the appropriate index in registered IIO channels array.
>
> Add simple translation function, suitable for the most 1:1
> mapped channels in IIO chips, and use it when driver did not
> provide custom implementation.
>
> Signed-off-by: Ivan T. Ivanov <iivanov@mm-sol.com>

Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>

Thanks.

Re: [PATCH v2] iio: inkern: Add of_xlate function to struct iio_info

[Jonathan Cameron]

On 22/10/14 16:32, Lars-Peter Clausen wrote:
> On 10/22/2014 05:29 PM, Ivan T. Ivanov wrote:
>> When #iio-cells is greater than '0', the driver could provide
>> a custom of_xlate function that reads the *args* and returns
>> the appropriate index in registered IIO channels array.
>>
>> Add simple translation function, suitable for the most 1:1
>> mapped channels in IIO chips, and use it when driver did not
>> provide custom implementation.
>>
>> Signed-off-by: Ivan T. Ivanov <iivanov@mm-sol.com>
> 
> Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
> 
Applied to the togreg branch of iio.git - initially pushed out as testing
for the autobuilders to play with it.

Thanks,

Jonathan

Re: [PATCH v2] iio: inkern: Add of_xlate function to struct iio_info

[Ivan T. Ivanov]

On Sat, 2014-10-25 at 11:04 +0100, Jonathan Cameron wrote:
> On 22/10/14 16:32, Lars-Peter Clausen wrote:
> > On 10/22/2014 05:29 PM, Ivan T. Ivanov wrote:
> > > When #iio-cells is greater than '0', the driver could provide
> > > a custom of_xlate function that reads the *args* and returns
> > > the appropriate index in registered IIO channels array.
> > > 
> > > Add simple translation function, suitable for the most 1:1
> > > mapped channels in IIO chips, and use it when driver did not
> > > provide custom implementation.
> > > 
> > > Signed-off-by: Ivan T. Ivanov <iivanov-NEYub+7Iv8PQT0dZR+AlfA@public.gmane.org>
> > 
> > Reviewed-by: Lars-Peter Clausen <lars-Qo5EllUWu/uELgA04lAiVw@public.gmane.org>
> > 
> Applied to the togreg branch of iio.git - initially pushed out as testing
> for the autobuilders to play with it.

Thank you. Probably my git skills failed me, but I can not
find it in aforementioned branches. Is it publicly pushed?

Regards,
Ivan

Re: [PATCH v2] iio: inkern: Add of_xlate function to struct iio_info

[Lars-Peter Clausen]

On 11/03/2014 11:07 AM, Ivan T. Ivanov wrote:
>
> On Sat, 2014-10-25 at 11:04 +0100, Jonathan Cameron wrote:
>> On 22/10/14 16:32, Lars-Peter Clausen wrote:
>>> On 10/22/2014 05:29 PM, Ivan T. Ivanov wrote:
>>>> When #iio-cells is greater than '0', the driver could provide
>>>> a custom of_xlate function that reads the *args* and returns
>>>> the appropriate index in registered IIO channels array.
>>>>
>>>> Add simple translation function, suitable for the most 1:1
>>>> mapped channels in IIO chips, and use it when driver did not
>>>> provide custom implementation.
>>>>
>>>> Signed-off-by: Ivan T. Ivanov <iivanov@mm-sol.com>
>>>
>>> Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
>>>
>> Applied to the togreg branch of iio.git - initially pushed out as testing
>> for the autobuilders to play with it.
>
> Thank you. Probably my git skills failed me, but I can not
> find it in aforementioned branches. Is it publicly pushed?

It's in the testing branch.

http://git.kernel.org/cgit/linux/kernel/git/jic23/iio.git/log/?h=testing

Re: [PATCH v2] iio: inkern: Add of_xlate function to struct iio_info

[Srinivas Pandruvada]

On Mon, 2014-11-03 at 12:07 +0200, Ivan T. Ivanov wrote:
> On Sat, 2014-10-25 at 11:04 +0100, Jonathan Cameron wrote:
> > On 22/10/14 16:32, Lars-Peter Clausen wrote:
> > > On 10/22/2014 05:29 PM, Ivan T. Ivanov wrote:
> > > > When #iio-cells is greater than '0', the driver could provide
> > > > a custom of_xlate function that reads the *args* and returns
> > > > the appropriate index in registered IIO channels array.
> > > > 
> > > > Add simple translation function, suitable for the most 1:1
> > > > mapped channels in IIO chips, and use it when driver did not
> > > > provide custom implementation.
> > > > 
> > > > Signed-off-by: Ivan T. Ivanov <iivanov@mm-sol.com>
> > > 
> > > Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
> > > 
> > Applied to the togreg branch of iio.git - initially pushed out as testing
> > for the autobuilders to play with it.
> 
> Thank you. Probably my git skills failed me, but I can not
> find it in aforementioned branches. Is it publicly pushed?
> 
check here
https://www.kernel.org/pub/scm/linux/kernel/git/jic23/iio.git
checkout branch: remotes/origin/testing

> Regards,
> Ivan
> 

Re: [PATCH v2] iio: inkern: Add of_xlate function to struct iio_info

[Ivan T. Ivanov]

On Mon, 2014-11-03 at 02:36 -0800, Srinivas Pandruvada wrote:
> On Mon, 2014-11-03 at 12:07 +0200, Ivan T. Ivanov wrote:
> > On Sat, 2014-10-25 at 11:04 +0100, Jonathan Cameron wrote:
> > > On 22/10/14 16:32, Lars-Peter Clausen wrote:
> > > > On 10/22/2014 05:29 PM, Ivan T. Ivanov wrote:
> > > > > When #iio-cells is greater than '0', the driver could provide
> > > > > a custom of_xlate function that reads the *args* and returns
> > > > > the appropriate index in registered IIO channels array.
> > > > > 
> > > > > Add simple translation function, suitable for the most 1:1
> > > > > mapped channels in IIO chips, and use it when driver did not
> > > > > provide custom implementation.
> > > > > 
> > > > > Signed-off-by: Ivan T. Ivanov <iivanov-NEYub+7Iv8PQT0dZR+AlfA@public.gmane.org>
> > > > 
> > > > Reviewed-by: Lars-Peter Clausen <lars-Qo5EllUWu/uELgA04lAiVw@public.gmane.org>
> > > > 
> > > Applied to the togreg branch of iio.git - initially pushed out as testing
> > > for the autobuilders to play with it.
> > 
> > Thank you. Probably my git skills failed me, but I can not
> > find it in aforementioned branches. Is it publicly pushed?
> > 
> check here
> https://www.kernel.org/pub/scm/linux/kernel/git/jic23/iio.git
> checkout branch: remotes/origin/testing

Thank you.
Ivan

Re: [PATCH v2] iio: inkern: Add of_xlate function to struct iio_info

[Ivan T. Ivanov]

On Mon, 2014-11-03 at 11:31 +0100, Lars-Peter Clausen wrote:
> On 11/03/2014 11:07 AM, Ivan T. Ivanov wrote:
> > On Sat, 2014-10-25 at 11:04 +0100, Jonathan Cameron wrote:
> > > On 22/10/14 16:32, Lars-Peter Clausen wrote:
> > > > On 10/22/2014 05:29 PM, Ivan T. Ivanov wrote:
> > > > > When #iio-cells is greater than '0', the driver could provide
> > > > > a custom of_xlate function that reads the *args* and returns
> > > > > the appropriate index in registered IIO channels array.
> > > > > 
> > > > > Add simple translation function, suitable for the most 1:1
> > > > > mapped channels in IIO chips, and use it when driver did not
> > > > > provide custom implementation.
> > > > > 
> > > > > Signed-off-by: Ivan T. Ivanov <iivanov-NEYub+7Iv8PQT0dZR+AlfA@public.gmane.org>
> > > > 
> > > > Reviewed-by: Lars-Peter Clausen <lars-Qo5EllUWu/uELgA04lAiVw@public.gmane.org>
> > > > 
> > > Applied to the togreg branch of iio.git - initially pushed out as testing
> > > for the autobuilders to play with it.
> > 
> > Thank you. Probably my git skills failed me, but I can not
> > find it in aforementioned branches. Is it publicly pushed?
> 
> It's in the testing branch.
> 
> http://git.kernel.org/cgit/linux/kernel/git/jic23/iio.git/log/?h=testing
> 

Thank you. Ivan