linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Brian Masney <masneyb@onstation.org>
To: jic23@kernel.org, linux-iio@vger.kernel.org
Cc: gregkh@linuxfoundation.org, devel@driverdev.osuosl.org,
	knaack.h@gmx.de, lars@metafoo.de, pmeerw@pmeerw.net,
	linux-kernel@vger.kernel.org, Jon.Brenner@ams.com
Subject: [PATCH 4/6] staging: iio: tsl2x7x: cleaned up i2c calls in tsl2x7x_als_calibrate()
Date: Thu, 29 Jun 2017 13:03:50 -0400	[thread overview]
Message-ID: <20170629170352.11264-5-masneyb@onstation.org> (raw)
In-Reply-To: <20170629170352.11264-1-masneyb@onstation.org>

The calibration function calls i2c_smbus_write_byte() and
i2c_smbus_read_byte(). These two function calls are replaced with a
single call to i2c_smbus_read_byte_data() by this patch. This patch
also removes an unnecessary call that reads the CNTRL register
a second time. One of the error paths returned -1 if the ADC was not
enabled and this patch changes that return value to -EINVAL.

Signed-off-by: Brian Masney <masneyb@onstation.org>
---
 drivers/staging/iio/light/tsl2x7x.c | 33 ++++++++++++---------------------
 1 file changed, 12 insertions(+), 21 deletions(-)

diff --git a/drivers/staging/iio/light/tsl2x7x.c b/drivers/staging/iio/light/tsl2x7x.c
index d917b9d..620f40c 100644
--- a/drivers/staging/iio/light/tsl2x7x.c
+++ b/drivers/staging/iio/light/tsl2x7x.c
@@ -542,39 +542,30 @@ static void tsl2x7x_defaults(struct tsl2X7X_chip *chip)
 static int tsl2x7x_als_calibrate(struct iio_dev *indio_dev)
 {
 	struct tsl2X7X_chip *chip = iio_priv(indio_dev);
-	u8 reg_val;
 	int gain_trim_val;
 	int ret;
 	int lux_val;
 
-	ret = i2c_smbus_write_byte(chip->client,
-				   (TSL2X7X_CMD_REG | TSL2X7X_CNTRL));
+	ret = i2c_smbus_read_byte_data(chip->client,
+				       TSL2X7X_CMD_REG | TSL2X7X_CNTRL);
 	if (ret < 0) {
 		dev_err(&chip->client->dev,
-			"failed to write CNTRL register, ret=%d\n", ret);
+			"%s: failed to read from the CNTRL register\n",
+			__func__);
 		return ret;
 	}
 
-	reg_val = i2c_smbus_read_byte(chip->client);
-	if ((reg_val & (TSL2X7X_CNTL_ADC_ENBL | TSL2X7X_CNTL_PWR_ON))
-		!= (TSL2X7X_CNTL_ADC_ENBL | TSL2X7X_CNTL_PWR_ON)) {
+	if ((ret & (TSL2X7X_CNTL_ADC_ENBL | TSL2X7X_CNTL_PWR_ON))
+			!= (TSL2X7X_CNTL_ADC_ENBL | TSL2X7X_CNTL_PWR_ON)) {
 		dev_err(&chip->client->dev,
-			"%s: failed: ADC not enabled\n", __func__);
-		return -1;
-	}
-
-	ret = i2c_smbus_write_byte(chip->client,
-				   (TSL2X7X_CMD_REG | TSL2X7X_CNTRL));
-	if (ret < 0) {
-		dev_err(&chip->client->dev,
-			"failed to write ctrl reg: ret=%d\n", ret);
-		return ret;
+			"%s: Device is not powered on and/or ADC is not enabled\n",
+			__func__);
+		return -EINVAL;
 	}
-
-	reg_val = i2c_smbus_read_byte(chip->client);
-	if ((reg_val & TSL2X7X_STA_ADC_VALID) != TSL2X7X_STA_ADC_VALID) {
+	else if ((ret & TSL2X7X_STA_ADC_VALID) != TSL2X7X_STA_ADC_VALID) {
 		dev_err(&chip->client->dev,
-			"%s: failed: STATUS - ADC not valid.\n", __func__);
+			"%s: The two ADC channels have not completed an integration cycle\n",
+			__func__);
 		return -ENODATA;
 	}
 
-- 
2.9.4

  parent reply	other threads:[~2017-06-29 17:12 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-06-29 17:03 [PATCH 0/6] staging: iio: tsl2x7x: staging cleanups Brian Masney
2017-06-29 17:03 ` [PATCH 1/6] staging: iio: tsl2x7x: add of_match table for device tree support Brian Masney
2017-07-06 18:55   ` Rob Herring
2017-06-29 17:03 ` [PATCH 2/6] staging: iio: tsl2x7x: remove redundant power_state sysfs attribute Brian Masney
2017-06-29 17:03 ` [PATCH 3/6] staging: iio: tsl2x7x: remove tsl2x7x_i2c_read() Brian Masney
2017-06-29 19:26   ` Frans Klaver
2017-06-29 17:03 ` Brian Masney [this message]
2017-06-29 17:03 ` [PATCH 5/6] staging: iio: tsl2x7x: refactor {read,write}_event_value to allow handling multiple iio_event_infos Brian Masney
2017-07-01  9:40   ` Jonathan Cameron
2017-07-01 10:37     ` Brian Masney
2017-07-01 11:58       ` Jonathan Cameron
2017-06-29 17:03 ` [PATCH 6/6] staging: iio: tsl2x7x: use usleep_range() instead of mdelay() Brian Masney
2017-06-30 15:21 ` [PATCH 0/6] staging: iio: tsl2x7x: staging cleanups Brian Masney
2017-06-30 16:08   ` Jon Brenner
2017-07-01  9:42   ` Jonathan Cameron

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20170629170352.11264-5-masneyb@onstation.org \
    --to=masneyb@onstation.org \
    --cc=Jon.Brenner@ams.com \
    --cc=devel@driverdev.osuosl.org \
    --cc=gregkh@linuxfoundation.org \
    --cc=jic23@kernel.org \
    --cc=knaack.h@gmx.de \
    --cc=lars@metafoo.de \
    --cc=linux-iio@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=pmeerw@pmeerw.net \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).