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authorJens Thiele <karme@karme.de>2015-03-23 19:04:56 +0300
committerDmitry Torokhov <dmitry.torokhov@gmail.com>2015-03-23 19:11:11 +0300
commit4ed0e032c3cf27c6fabc154164d003c4e0ac4654 (patch)
tree47d8d96c7aa31f08c835777903bda70073601254
parent68c581d5e7d834d8e97534cafd60bd6716ee6fbc (diff)
downloadlinux-4ed0e032c3cf27c6fabc154164d003c4e0ac4654.tar.xz
Input: sun4i-ts - allow controlling filter and sensitivity via DT
This commit introduces two new optional device-tree properties: "tp-sensitive-adjust": adjust sensitivity of pen down detection "filter-type": select median and averaging filter The previous fixed defaults, didn't work well for the Olimex A13-LCD10TS (I have). Signed-off-by: Jens Thiele <karme@karme.de> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
-rw-r--r--Documentation/devicetree/bindings/input/touchscreen/sun4i.txt19
-rw-r--r--drivers/input/touchscreen/sun4i-ts.c20
2 files changed, 33 insertions, 6 deletions
diff --git a/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt b/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt
index d59d25281e9f..89abecd938cb 100644
--- a/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt
+++ b/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt
@@ -9,8 +9,20 @@ Required properties:
- #thermal-sensor-cells: shall be 0
Optional properties:
- - allwinner,ts-attached: boolean indicating that an actual touchscreen is
- attached to the controller
+ - allwinner,ts-attached : boolean indicating that an actual touchscreen
+ is attached to the controller
+ - allwinner,tp-sensitive-adjust : integer (4 bits)
+ adjust sensitivity of pen down detection
+ between 0 (least sensitive) and 15
+ (defaults to 15)
+ - allwinner,filter-type : integer (2 bits)
+ select median and averaging filter
+ samples used for median / averaging filter
+ 0: 4/2
+ 1: 5/3
+ 2: 8/4
+ 3: 16/8
+ (defaults to 1)
Example:
@@ -20,4 +32,7 @@ Example:
interrupts = <29>;
allwinner,ts-attached;
#thermal-sensor-cells = <0>;
+ /* sensitive/noisy touch panel */
+ allwinner,tp-sensitive-adjust = <0>;
+ allwinner,filter-type = <3>;
};
diff --git a/drivers/input/touchscreen/sun4i-ts.c b/drivers/input/touchscreen/sun4i-ts.c
index 178d2efb8353..c0116994067d 100644
--- a/drivers/input/touchscreen/sun4i-ts.c
+++ b/drivers/input/touchscreen/sun4i-ts.c
@@ -30,6 +30,10 @@
* These kinds of heuristics are just asking for trouble (and don't belong
* in the kernel). So this driver offers straight forward, reliable single
* touch functionality only.
+ *
+ * s.a. A20 User Manual "1.15 TP" (Documentation/arm/sunxi/README)
+ * (looks like the description in the A20 User Manual v1.3 is better
+ * than the one in the A10 User Manual v.1.5)
*/
#include <linux/err.h>
@@ -246,6 +250,8 @@ static int sun4i_ts_probe(struct platform_device *pdev)
int error;
u32 reg;
bool ts_attached;
+ u32 tp_sensitive_adjust = 15;
+ u32 filter_type = 1;
ts = devm_kzalloc(dev, sizeof(struct sun4i_ts_data), GFP_KERNEL);
if (!ts)
@@ -322,14 +328,20 @@ static int sun4i_ts_probe(struct platform_device *pdev)
ts->base + TP_CTRL0);
/*
- * sensitive_adjust = 15 : max, which is not all that sensitive,
+ * tp_sensitive_adjust is an optional property
* tp_mode = 0 : only x and y coordinates, as we don't use dual touch
*/
- writel(TP_SENSITIVE_ADJUST(15) | TP_MODE_SELECT(0),
+ of_property_read_u32(np, "allwinner,tp-sensitive-adjust",
+ &tp_sensitive_adjust);
+ writel(TP_SENSITIVE_ADJUST(tp_sensitive_adjust) | TP_MODE_SELECT(0),
ts->base + TP_CTRL2);
- /* Enable median filter, type 1 : 5/3 */
- writel(FILTER_EN(1) | FILTER_TYPE(1), ts->base + TP_CTRL3);
+ /*
+ * Enable median and averaging filter, optional property for
+ * filter type.
+ */
+ of_property_read_u32(np, "allwinner,filter-type", &filter_type);
+ writel(FILTER_EN(1) | FILTER_TYPE(filter_type), ts->base + TP_CTRL3);
/* Enable temperature measurement, period 1953 (2 seconds) */
writel(TEMP_ENABLE(1) | TEMP_PERIOD(1953), ts->base + TP_TPR);