From fe4f1275b2f596dd5ebc8e5594176d6128b46b04 Mon Sep 17 00:00:00 2001 From: Vic Yang Date: Thu, 29 May 2014 11:15:14 -0700 Subject: Keyborg: improve panel discharge This fix includes: - A faster discharge procedure - Added discharge steps between scanning two columns. This is to prevent the shadow "wraps around" to the beginning of the next column, which is much harder to filter out. BUG=None TEST=Press hard on the end of one column. Check the shadow doesn't wrap around to the next column. BRANCH=None Change-Id: Ie1342f7778d0fe18a0ec2086af79d5e459f1cd7d Signed-off-by: Vic Yang Reviewed-on: https://chromium-review.googlesource.com/202073 Reviewed-by: Vincent Palatin --- board/keyborg/touch_scan.c | 20 ++++++++++++++++++-- 1 file changed, 18 insertions(+), 2 deletions(-) diff --git a/board/keyborg/touch_scan.c b/board/keyborg/touch_scan.c index 5e4044215b..b69ccfe33f 100644 --- a/board/keyborg/touch_scan.c +++ b/board/keyborg/touch_scan.c @@ -81,6 +81,18 @@ void touch_scan_init(void) mccr_list[i] = TS_PIN_TO_CR(col_pins[i]); } +static void discharge(void) +{ + int i; + + /* + * The value 20 is deducted from experiments. + * Somehow this needs to be in reverse order + */ + for (i = 20; i >= 0; --i) + STM32_PMSE_MRCR = mrcr_list[i]; +} + static void start_adc_sample(int id, int wait_cycle) { /* Clear EOC and STRT bit */ @@ -202,7 +214,7 @@ void touch_scan_slave_start(void) return; /* Discharge the panel */ - scan_column(buf[0]); + discharge(); for (col = 0; col < COL_COUNT * 2; ++col) { if (col < COL_COUNT) { @@ -239,10 +251,12 @@ void touch_scan_slave_start(void) /* Start sending the response for the current column */ spi_slave_send_response_async(resp); + /* Disable the current column and discharge */ if (col < COL_COUNT) { enable_col(col, 0); STM32_PMSE_MCCR = 0; } + discharge(); } spi_slave_send_response_flush(); master_slave_sync(20); @@ -268,7 +282,7 @@ int touch_scan_full_matrix(void) return EC_ERROR_UNKNOWN; /* Discharge the panel */ - scan_column(buf[0]); + discharge(); for (col = 0; col < COL_COUNT * 2; ++col) { if (col >= COL_COUNT) { @@ -306,10 +320,12 @@ int touch_scan_full_matrix(void) if (spi_master_wait_response_async() != EC_SUCCESS) return EC_ERROR_UNKNOWN; + /* Disable the current column and discharge */ if (col >= COL_COUNT) { enable_col(col - COL_COUNT, 0); STM32_PMSE_MCCR = 0; } + discharge(); } resp = spi_master_wait_response_done(); -- cgit v1.2.1