Re: [PATCH V3 1/2] tps6507x-ts: Add DT support

Hi Prabhakar,

On Tue, Aug 20, 2013 at 11:44 AM, Prabhakar Lad
[off-list ref] wrote:

Hi Manish,

Thanks for the patch.

On Tue, May 21, 2013 at 2:24 PM, Vishwanathrao Badarkhe, Manish
[off-list ref] wrote:

quoted

Add device tree based support for TI's tps6507x touchscreen.

Tested on da850-evm.

Signed-off-by: Vishwanathrao Badarkhe, Manish <redacted>
---
Changes since V2:
 - Removed unnecessary code.
 - Updated Documentation to provide proper names of
   devicetree properties.

Changes since V1:
 - Updated documentation to specify tps6507x as multifunctional
   device.
 - return proper error value in absence of platform and DT
   data for touchscreen.
 - Updated commit message.

:100755 100755 8fffa3c... 65ee2cd... M  Documentation/devicetree/bindings/mfd/tps6507x.txt
:100644 100644 65e0f9a... 89232ee... M  drivers/input/touchscreen/tps6507x-ts.c
 Documentation/devicetree/bindings/mfd/tps6507x.txt |   28 ++++++-
 drivers/input/touchscreen/tps6507x-ts.c            |   98 ++++++++++++++------
 2 files changed, 95 insertions(+), 31 deletions(-)

diff --git a/Documentation/devicetree/bindings/mfd/tps6507x.txt b/Documentation/devicetree/bindings/mfd/tps6507x.txt
index 8fffa3c..65ee2cd 100755
--- a/Documentation/devicetree/bindings/mfd/tps6507x.txt
+++ b/Documentation/devicetree/bindings/mfd/tps6507x.txt

@@ -1,4 +1,8 @@
-TPS6507x Power Management Integrated Circuit
+TPS6507x Multifunctional Device.
+
+Features provided by TPS6507x:
+        1.Power Management Integrated Circuit.
+        2.Touch-Screen.

 Required properties:
 - compatible: "ti,tps6507x"

@@ -23,6 +27,12 @@ Required properties:
        vindcdc1_2-supply: VDCDC1 and VDCDC2 input.
        vindcdc3-supply  : VDCDC3 input.
        vldo1_2-supply   : VLDO1 and VLDO2 input.
+- tsc: This node specifies touch screen data.
+       ti,poll-period : Time at which touch input is getting sampled in ms.
+       ti,min-pressure: Minimum pressure value to trigger touch.
+       ti,vref        : voltage reference for ADC.
+                     0: Reference voltage for ADC is disabled.
+                     1: Reference voltage for ADC is enabled.

 Regulator Optional properties:
 - defdcdc_default: It's property of DCDC2 and DCDC3 regulators.

@@ -30,6 +40,14 @@ Regulator Optional properties:
                        1: If defdcdc pin of DCDC2/DCDC3 is driven HIGH.
   If this property is not defined, it defaults to 0 (not enabled).

+Touchscreen Optional properties:
+- ti,vendor : Touchscreen vendor id to populate
+             in sysclass interface.
+- ti,product: Touchscreen product id to populate
+             in sysclass interface.
+- ti,version: Touchscreen version id to populate
+             in sysclass interface.
+
 Example:

        pmu: tps6507x@48 {

@@ -88,4 +106,12 @@ Example:
                        };
                };

+               tsc {
+                       ti,poll-period = <30>;
+                       ti,min-pressure = <0x30>;
+                       ti,vref = <0>;
+                       ti,vendor = <0>;
+                       ti,product = <65070>;
+                       ti,version = <0x100>;
+               };
        };

diff --git a/drivers/input/touchscreen/tps6507x-ts.c b/drivers/input/touchscreen/tps6507x-ts.c
index 65e0f9a..89232ee 100644
--- a/drivers/input/touchscreen/tps6507x-ts.c
+++ b/drivers/input/touchscreen/tps6507x-ts.c

@@ -21,6 +21,8 @@
 #include <linux/mfd/tps6507x.h>
 #include <linux/input/tps6507x-ts.h>
 #include <linux/delay.h>
+#include <linux/of.h>
+#include <linux/of_device.h>

 #define TSC_DEFAULT_POLL_PERIOD 30 /* ms */
 #define TPS_DEFAULT_MIN_PRESSURE 0x30

@@ -231,36 +233,76 @@ done:
        ret = tps6507x_adc_standby(tsc);
 }

+static int tsc_init_data(struct tps6507x_dev *tps6507x_dev,
+               struct input_dev *input_dev)
+{
+       struct device_node *node = tps6507x_dev->dev->of_node;
+       struct tps6507x_board *tps_board =
+               (struct tps6507x_board *)tps6507x_dev->dev->platform_data;
+       struct touchscreen_init_data *init_data = NULL;
+       int err;
+
+       if (node)
+               node = of_find_node_by_name(node, "tsc");
+       if (tps_board)
+               init_data = tps_board->tps6507x_ts_init_data;
+
+       if (node == NULL || init_data == NULL) {
+               err = -EINVAL;
+               goto error_ret;
+       } else if (init_data) {
+               tps6507x_dev->ts->poll_period = init_data->poll_period;
+               tps6507x_dev->ts->min_pressure = init_data->min_pressure;
+               tps6507x_dev->ts->vref = init_data->vref;
+               input_dev->id.vendor = init_data->vendor;
+               input_dev->id.product = init_data->product;
+               input_dev->id.version = init_data->version;
+       } else if (node) {
+               err = of_property_read_u32(node, "ti,poll-period",
+                                       (u32 *)&tps6507x_dev->ts->poll_period);
+               if (err < 0)
+                       goto error_ret;
+
+               err = of_property_read_u16(node, "ti,min-pressure",
+                                       &tps6507x_dev->ts->min_pressure);
+               if (err < 0)
+                       goto error_ret;
+
+               err = of_property_read_u32(node, "ti,vref",
+                                       &tps6507x_dev->ts->vref);
+               if (err < 0)
+                       goto error_ret;
+
+               err = of_property_read_u16(node, "ti,vendor",
+                                       &input_dev->id.vendor);
+               if (err < 0)
+                       goto error_ret;
+
+               err = of_property_read_u16(node, "ti,product",
+                                       &input_dev->id.product);
+               if (err < 0)
+                       goto error_ret;
+
+               err = of_property_read_u16(node, "ti,version",
+                                       &input_dev->id.version);
+               if (err < 0)
+                       goto error_ret;

All the three above properties as per the documentation  above
are optional, but the code here makes them required property.
May be what you can do is if property is not defined make it as
zero as per documentation.

I already taken care of this as per Dmitry's comment but not yet
posted patch series as
there is discussion going on populating child node's properties.


Regards
Manish Badarkhe