hans-christian.egtvedt at atmel
Jul 7, 2008, 5:11 AM
Post #1 of 1
(63 views)
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[PATCH 1/1] Optimize order of calculating Rt in ads7846_rx function
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This patch alters the if expression for calculating Rt. The old implementation
would run unnecessary code when the ADS7843 device was used.
The patch also fixes the code style to kernel standard.
Signed-off-by: Hans-Christian Egtvedt <hans-christian.egtvedt[at]atmel.com>
---
drivers/input/touchscreen/ads7846.c | 10 +++++-----
1 files changed, 5 insertions(+), 5 deletions(-)
diff --git a/drivers/input/touchscreen/ads7846.c b/drivers/input/touchscreen/ads7846.c
index 57a1c28..3044fad 100644
--- a/drivers/input/touchscreen/ads7846.c
+++ b/drivers/input/touchscreen/ads7846.c
@@ -527,7 +527,9 @@ static void ads7846_rx(void *ads)
if (x == MAX_12BIT)
x = 0;
- if (likely(x && z1)) {
+ if (ts->model == 7843) {
+ Rt = ts->pressure_max / 2;
+ } else if (likely(x && z1)) {
/* compute touch pressure resistance using equation #2 */
Rt = z2;
Rt -= z1;
@@ -535,11 +537,9 @@ static void ads7846_rx(void *ads)
Rt *= ts->x_plate_ohms;
Rt /= z1;
Rt = (Rt + 2047) >> 12;
- } else
+ } else {
Rt = 0;
-
- if (ts->model == 7843)
- Rt = ts->pressure_max / 2;
+ }
/* Sample found inconsistent by debouncing or pressure is beyond
* the maximum. Don't report it to user space, repeat at least
--
1.5.4.3
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