Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760055Ab3GSJNy (ORCPT ); Fri, 19 Jul 2013 05:13:54 -0400 Received: from mail1.bemta12.messagelabs.com ([216.82.251.16]:27287 "EHLO mail1.bemta12.messagelabs.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751456Ab3GSJNv (ORCPT ); Fri, 19 Jul 2013 05:13:51 -0400 X-Env-Sender: Hector.Palacios@digi.com X-Msg-Ref: server-11.tower-29.messagelabs.com!1374225229!23329061!1 X-Originating-IP: [66.77.174.14] X-StarScan-Received: X-StarScan-Version: 6.9.11; banners=-,-,- X-VirusChecked: Checked From: Hector Palacios To: CC: , , , , , , , Subject: [PATCH v2 1/5] iio: mxs-lradc: change the realbits to 12 Date: Fri, 19 Jul 2013 11:13:24 +0200 Message-ID: <1374225208-28940-2-git-send-email-hector.palacios@digi.com> X-Mailer: git-send-email 1.8.3 In-Reply-To: <1374225208-28940-1-git-send-email-hector.palacios@digi.com> References: <1374225208-28940-1-git-send-email-hector.palacios@digi.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2434 Lines: 57 The LRADC virtual channels have an 18 bit field to store the sum of up to 2^5 accumulated samples. The read_raw function however only operates over a single sample (12 bit resolution). In order to use this field for scaling operations, we need it to be the exact resolution value of the LRADC. Besides, the driver was using an 18 bit mask (LRADC_CH_VALUE_MASK) to report touch coordinates to userland. A 12 bit mask should be used instead or else the touch libraries will expect a coordinates range between 0 and 0x3ffff (18 bits), instead of between 0 and 0xfff (12 bits). Signed-off-by: Hector Palacios --- drivers/staging/iio/adc/mxs-lradc.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/drivers/staging/iio/adc/mxs-lradc.c b/drivers/staging/iio/adc/mxs-lradc.c index d92c97a..91282dc 100644 --- a/drivers/staging/iio/adc/mxs-lradc.c +++ b/drivers/staging/iio/adc/mxs-lradc.c @@ -225,6 +225,9 @@ struct mxs_lradc { #define LRADC_CTRL4_LRADCSELECT_MASK(n) (0xf << ((n) * 4)) #define LRADC_CTRL4_LRADCSELECT_OFFSET(n) ((n) * 4) +#define LRADC_RESOLUTION 12 +#define LRADC_SINGLE_SAMPLE_MASK ((1 << LRADC_RESOLUTION) - 1) + /* * Raw I/O operations */ @@ -547,9 +550,10 @@ static int mxs_lradc_ts_register(struct mxs_lradc *lradc) __set_bit(EV_ABS, input->evbit); __set_bit(EV_KEY, input->evbit); __set_bit(BTN_TOUCH, input->keybit); - input_set_abs_params(input, ABS_X, 0, LRADC_CH_VALUE_MASK, 0, 0); - input_set_abs_params(input, ABS_Y, 0, LRADC_CH_VALUE_MASK, 0, 0); - input_set_abs_params(input, ABS_PRESSURE, 0, LRADC_CH_VALUE_MASK, 0, 0); + input_set_abs_params(input, ABS_X, 0, LRADC_SINGLE_SAMPLE_MASK, 0, 0); + input_set_abs_params(input, ABS_Y, 0, LRADC_SINGLE_SAMPLE_MASK, 0, 0); + input_set_abs_params(input, ABS_PRESSURE, 0, LRADC_SINGLE_SAMPLE_MASK, + 0, 0); lradc->ts_input = input; input_set_drvdata(input, lradc); @@ -821,7 +825,7 @@ static const struct iio_buffer_setup_ops mxs_lradc_buffer_ops = { .channel = (idx), \ .scan_type = { \ .sign = 'u', \ - .realbits = 18, \ + .realbits = LRADC_RESOLUTION, \ .storagebits = 32, \ }, \ } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/