Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752791AbcD2TFh (ORCPT ); Fri, 29 Apr 2016 15:05:37 -0400 Received: from mga03.intel.com ([134.134.136.65]:36806 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752639AbcD2TFg (ORCPT ); Fri, 29 Apr 2016 15:05:36 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.24,552,1455004800"; d="scan'208";a="94450248" From: Crestez Dan Leonard To: Jonathan Cameron , linux-iio@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Hartmut Knaack , Lars-Peter Clausen , Peter Meerwald-Stadler , Daniel Baluta , Crestez Dan Leonard Subject: [PATCH] iio: ak8975: Support adapters limited to BYTE_DATA Date: Fri, 29 Apr 2016 22:05:32 +0300 Message-Id: X-Mailer: git-send-email 2.5.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2470 Lines: 71 The device has simple 8-bit registers but the driver incorrectly uses block or word reads without checking functionality bits. Fix by using i2c_smbus_read_i2c_block_data_or_emulated instead of i2c_smbus_read_i2c_block_data or i2c_smbus_read_word_data. This will check functionality bits and use the fastest available transfer method. Signed-off-by: Crestez Dan Leonard --- drivers/iio/magnetometer/ak8975.c | 20 ++++++++++++-------- 1 file changed, 12 insertions(+), 8 deletions(-) diff --git a/drivers/iio/magnetometer/ak8975.c b/drivers/iio/magnetometer/ak8975.c index dbf0661..c24b8a5 100644 --- a/drivers/iio/magnetometer/ak8975.c +++ b/drivers/iio/magnetometer/ak8975.c @@ -430,8 +430,8 @@ static int ak8975_who_i_am(struct i2c_client *client, * AK8975 | DEVICE_ID | NA * AK8963 | DEVICE_ID | NA */ - ret = i2c_smbus_read_i2c_block_data(client, AK09912_REG_WIA1, - 2, wia_val); + ret = i2c_smbus_read_i2c_block_data_or_emulated( + client, AK09912_REG_WIA1, 2, wia_val); if (ret < 0) { dev_err(&client->dev, "Error reading WIA\n"); return ret; @@ -543,9 +543,9 @@ static int ak8975_setup(struct i2c_client *client) } /* Get asa data and store in the device data. */ - ret = i2c_smbus_read_i2c_block_data(client, - data->def->ctrl_regs[ASA_BASE], - 3, data->asa); + ret = i2c_smbus_read_i2c_block_data_or_emulated( + client, data->def->ctrl_regs[ASA_BASE], + 3, data->asa); if (ret < 0) { dev_err(&client->dev, "Not able to read asa data\n"); return ret; @@ -686,6 +686,7 @@ static int ak8975_read_axis(struct iio_dev *indio_dev, int index, int *val) struct ak8975_data *data = iio_priv(indio_dev); const struct i2c_client *client = data->client; const struct ak_def *def = data->def; + u16 buff; int ret; mutex_lock(&data->lock); @@ -694,14 +695,17 @@ static int ak8975_read_axis(struct iio_dev *indio_dev, int index, int *val) if (ret) goto exit; - ret = i2c_smbus_read_word_data(client, def->data_regs[index]); + ret = i2c_smbus_read_i2c_block_data_or_emulated( + client, def->data_regs[index], + sizeof(buff), (u8*)&buff); if (ret < 0) goto exit; mutex_unlock(&data->lock); - /* Clamp to valid range. */ - *val = clamp_t(s16, ret, -def->range, def->range); + /* Swap bytes and convert to valid range. */ + buff = le16_to_cpu(buff); + *val = clamp_t(s16, buff, -def->range, def->range); return IIO_VAL_INT; exit: -- 2.5.5