Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751766AbaKYWoY (ORCPT ); Tue, 25 Nov 2014 17:44:24 -0500 Received: from mail-wg0-f45.google.com ([74.125.82.45]:55705 "EHLO mail-wg0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751571AbaKYWoV convert rfc822-to-8bit (ORCPT ); Tue, 25 Nov 2014 17:44:21 -0500 MIME-Version: 1.0 In-Reply-To: <5475035C.8040107@gmx.de> References: <1416329275-7130-1-git-send-email-daniel.baluta@intel.com> <5473D111.9050509@gmx.de> <5475035C.8040107@gmx.de> Date: Wed, 26 Nov 2014 00:44:20 +0200 X-Google-Sender-Auth: nK-LCZj9KjFDupuzjVf4OP7fTwI Message-ID: Subject: Re: [PATCH v3] iio: imu: Add support for Kionix KMX61 sensor From: Daniel Baluta To: Hartmut Knaack Cc: Daniel Baluta , Jonathan Cameron , Peter Meerwald , Srinivas Pandruvada , "linux-iio@vger.kernel.org" , Linux Kernel Mailing List Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Nov 26, 2014 at 12:31 AM, Hartmut Knaack wrote: > Daniel Baluta schrieb am 25.11.2014 10:54: >> On Tue, Nov 25, 2014 at 2:45 AM, Hartmut Knaack wrote: >>> Daniel Baluta schrieb am 18.11.2014 17:47: >>>> Minimal implementation for KMX61 6-axis accelerometer/magnetometer. It exports >>>> raw accel/magn readings together with scale and sampling frequency. >>>> >>>> Datasheet will be available at: >>>> http://www.kionix.com/6-axis-accelerometer-magnetometer/kmx61 >>>> >>> Finally managed to have a close look, and found a few issues. >>>> Signed-off-by: Daniel Baluta >>>> --- >>>> Changes since v2: >>>> * mostly style fixes after comments received from Jonathan and Peter >>>> * http://marc.info/?l=linux-iio&m=141564019602400&w=2 >>>> * implemented PM runtime and PM sleep resume/suspend hooks >>>> * introduced new parameter for kmx61_set_mode to help updating >>>> stby bits in kmx61_data. >>>> * use kmx6111021 instead of kmx61 for i2c_device_id. >>>> >>>> drivers/iio/imu/Kconfig | 9 + >>>> drivers/iio/imu/Makefile | 2 + >>>> drivers/iio/imu/kmx61.c | 766 +++++++++++++++++++++++++++++++++++++++++++++++ >>>> 3 files changed, 777 insertions(+) >>>> create mode 100644 drivers/iio/imu/kmx61.c >>>> >>>> diff --git a/drivers/iio/imu/Kconfig b/drivers/iio/imu/Kconfig >>>> index 2b0e451..d675f43 100644 >>>> --- a/drivers/iio/imu/Kconfig >>>> +++ b/drivers/iio/imu/Kconfig >>>> @@ -25,6 +25,15 @@ config ADIS16480 >>>> Say yes here to build support for Analog Devices ADIS16375, ADIS16480, >>>> ADIS16485, ADIS16488 inertial sensors. >>>> >>>> +config KMX61 >>>> + tristate "Kionix KMX61 6-axis accelerometer and magnetometer" >>>> + depends on I2C >>>> + help >>>> + Say Y here if you want to build a driver for Kionix KMX61 6-axis accelerometer >>>> + and magnetometer. >>>> + To compile this driver as module, choose M here: the module will be called >>>> + kmx61. >>>> + >>> This help text is more than 80 characters wide and may better be wrapped a bit differently. >> >> Good catch. checkpatch.pl didn't complain. >> >>>> source "drivers/iio/imu/inv_mpu6050/Kconfig" >>>> >>>> endmenu >>>> diff --git a/drivers/iio/imu/Makefile b/drivers/iio/imu/Makefile >>>> index 114d2c1..e1e6e3d 100644 >>>> --- a/drivers/iio/imu/Makefile >>>> +++ b/drivers/iio/imu/Makefile >>>> @@ -14,3 +14,5 @@ adis_lib-$(CONFIG_IIO_ADIS_LIB_BUFFER) += adis_buffer.o >>>> obj-$(CONFIG_IIO_ADIS_LIB) += adis_lib.o >>>> >>>> obj-y += inv_mpu6050/ >>>> + >>>> +obj-$(CONFIG_KMX61) += kmx61.o >>>> diff --git a/drivers/iio/imu/kmx61.c b/drivers/iio/imu/kmx61.c >>>> new file mode 100644 >>>> index 0000000..f68b3ef >>>> --- /dev/null >>>> +++ b/drivers/iio/imu/kmx61.c >>>> @@ -0,0 +1,766 @@ >>>> +/* >>>> + * KMX61 - Kionix 6-axis Accelerometer/Magnetometer >>>> + * >>>> + * Copyright (c) 2014, Intel Corporation. >>>> + * >>>> + * This file is subject to the terms and conditions of version 2 of >>>> + * the GNU General Public License. See the file COPYING in the main >>>> + * directory of this archive for more details. >>>> + * >>>> + * IIO driver for KMX61 (7-bit I2C slave address 0x0E or 0x0F). >>>> + * >>>> + * TODO: buffer, interrupt, thresholds, acpi, temperature sensor >>>> + * >>>> + */ >>>> + >>>> +#include >>>> +#include >>>> +#include >>>> +#include >>>> +#include >>>> +#include >>>> + >>>> +#define KMX61_DRV_NAME "kmx61" >>>> + >>>> +#define KMX61_REG_WHO_AM_I 0x00 >>>> + >>>> +/* >>>> + * three 16-bit accelerometer output registers for X/Y/Z axis >>>> + * we use only XOUT_L as a base register, all other addresses >>>> + * can be obtained by applying an offset and are provided here >>>> + * only for clarity. >>>> + */ >>>> +#define KMX61_ACC_XOUT_L 0x0A >>>> +#define KMX61_ACC_XOUT_H 0x0B >>>> +#define KMX61_ACC_YOUT_L 0x0C >>>> +#define KMX61_ACC_YOUT_H 0x0D >>>> +#define KMX61_ACC_ZOUT_L 0x0E >>>> +#define KMX61_ACC_ZOUT_H 0x0F >>>> + >>>> +/* >>>> + * one 16-bit temperature output register >>>> + */ >>>> +#define KMX61_TEMP_L 0x10 >>>> +#define KMX61_TEMP_H 0x11 >>>> + >>>> +/* >>>> + * three 16-bit magnetometer output registers for X/Y/Z axis >>>> + */ >>>> +#define KMX61_MAG_XOUT_L 0x12 >>>> +#define KMX61_MAG_XOUT_H 0x13 >>>> +#define KMX61_MAG_YOUT_L 0x14 >>>> +#define KMX61_MAG_YOUT_H 0x15 >>>> +#define KMX61_MAG_ZOUT_L 0x16 >>>> +#define KMX61_MAG_ZOUT_H 0x17 >>>> + >>>> +#define KMX61_REG_ODCNTL 0x2C >>>> +#define KMX61_REG_STBY 0x29 >>>> +#define KMX61_REG_CTRL1 0x2A >>>> + >>>> +#define KMX61_ACC_STBY_BIT BIT(0) >>>> +#define KMX61_MAG_STBY_BIT BIT(1) >>>> +#define KMX61_ACT_STBY_BIT BIT(7) >>>> + >>>> +#define KMX61_ALL_STBY (KMX61_ACC_STBY_BIT | KMX61_MAG_STBY_BIT) >>>> + >>>> +#define KMX61_REG_CTRL1_GSEL0_SHIFT 0 >>>> +#define KMX61_REG_CTRL1_GSEL1_SHIFT 1 >>>> +#define KMX61_REG_CTRL1_GSEL0_MASK 0x01 >>>> +#define KMX61_REG_CTRL1_GSEL1_MASK 0x02 >>> I don't see the benefit of separating GSEL0 and GSEL1. >>>> + >>>> +#define KMX61_REG_CTRL1_BIT_RES BIT(4) >>>> + >>>> +#define KMX61_ACC_ODR_SHIFT 0 >>>> +#define KMX61_MAG_ODR_SHIFT 4 >>>> +#define KMX61_ACC_ODR_MASK 0x0F >>>> +#define KMX61_MAG_ODR_MASK 0xF0 >>>> + >>>> +#define KMX61_SLEEP_DELAY_MS 2000 >>>> + >>>> +#define KMX61_CHIP_ID 0x12 >>>> + >>>> +struct kmx61_data { >>>> + struct i2c_client *client; >>>> + >>>> + /* serialize access to non-atomic ops, e.g set_mode */ >>>> + struct mutex lock; >>>> + u8 range; >>>> + u8 odr_bits; >>>> + >>>> + /* standby state */ >>>> + u8 acc_stby; >>>> + u8 mag_stby; >>> Why u8 instead of bool? >> >> Hmm, correct. I was thinking bitwise, but you are right. Will fix. >> >>>> + >>>> + /* power state */ >>>> + bool acc_ps; >>>> + bool mag_ps; >>>> +}; >>>> + >>>> +enum kmx61_range { >>>> + KMX61_RANGE_2G, >>>> + KMX61_RANGE_4G, >>>> + KMX61_RANGE_8G, >>>> +}; >>>> + >>>> +enum kmx61_scan { >>>> + KMX61_SCAN_ACC_X, >>>> + KMX61_SCAN_ACC_Y, >>>> + KMX61_SCAN_ACC_Z, >>>> + KMX61_SCAN_TEMP, >>>> + KMX61_SCAN_MAG_X, >>>> + KMX61_SCAN_MAG_Y, >>>> + KMX61_SCAN_MAG_Z, >>>> +}; >>>> + >>>> +static const struct { >>>> + u16 uscale; >>>> + u8 gsel0; >>>> + u8 gsel1; >>>> +} kmx61_scale_table[] = { >>>> + {9582, 0, 0}, >>>> + {19163, 1, 0}, >>>> + {38326, 0, 1}, >>> Why not consolidate gsel0 and gsel1 to gsel? Then this could become u16 kmx61_scale[] = {9582, 19163, 38326} with gsel as index. >> >> True. Will fix. >> >>>> +}; >>>> + >>>> +/* KMX61 devices */ >>>> +#define KMX61_ACC 0x01 >>>> +#define KMX61_MAG 0x02 >>>> + >>>> +static const struct { >>>> + int val; >>>> + int val2; >>>> + u8 odr_bits; >>>> +} kmx61_samp_freq_table[] = { {12, 500000, 0x00}, >>>> + {25, 0, 0x01}, >>>> + {50, 0, 0x02}, >>>> + {100, 0, 0x03}, >>>> + {200, 0, 0x04}, >>>> + {400, 0, 0x05}, >>>> + {800, 0, 0x06}, >>>> + {1600, 0, 0x07}, >>>> + {0, 781000, 0x08}, >>>> + {1, 563000, 0x09}, >>>> + {3, 125000, 0x0A}, >>>> + {6, 250000, 0x0B} }; >>>> + >>>> +static IIO_CONST_ATTR(accel_scale_available, "0.009582 0.019163 0.038326"); >>>> +static IIO_CONST_ATTR(magn_scale_available, "0.001465"); >>>> +static IIO_CONST_ATTR_SAMP_FREQ_AVAIL( >>>> + "0.781000 1.563000 3.125000 6.250000 12.500000 25 50 100 200 400 800"); >>>> + >>>> +static struct attribute *kmx61_attributes[] = { >>>> + &iio_const_attr_accel_scale_available.dev_attr.attr, >>>> + &iio_const_attr_magn_scale_available.dev_attr.attr, >>>> + &iio_const_attr_sampling_frequency_available.dev_attr.attr, >>>> + NULL, >>>> +}; >>>> + >>>> +static const struct attribute_group kmx61_attribute_group = { >>>> + .attrs = kmx61_attributes, >>>> +}; >>>> + >>>> +#define KMX61_ACC_CHAN(_axis, _index) { \ >>>> + .type = IIO_ACCEL, \ >>>> + .modified = 1, \ >>>> + .channel2 = IIO_MOD_ ## _axis, \ >>>> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ >>>> + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \ >>>> + BIT(IIO_CHAN_INFO_SAMP_FREQ), \ >>>> + .address = KMX61_ACC, \ >>>> + .scan_index = _index, \ >>>> + .scan_type = { \ >>>> + .sign = 's', \ >>>> + .realbits = 12, \ >>>> + .storagebits = 16, \ >>>> + .shift = 4, \ >>>> + .endianness = IIO_LE, \ >>>> + }, \ >>>> +} >>>> + >>>> +#define KMX61_MAG_CHAN(_axis, _index) { \ >>>> + .type = IIO_MAGN, \ >>>> + .modified = 1, \ >>>> + .channel2 = IIO_MOD_ ## _axis, \ >>>> + .address = KMX61_MAG, \ >>>> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ >>>> + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \ >>>> + BIT(IIO_CHAN_INFO_SAMP_FREQ), \ >>>> + .scan_index = _index, \ >>>> + .scan_type = { \ >>>> + .sign = 's', \ >>>> + .realbits = 14, \ >>>> + .storagebits = 16, \ >>>> + .shift = 2, \ >>>> + .endianness = IIO_LE, \ >>>> + }, \ >>>> +} >>>> + >>>> +static const struct iio_chan_spec kmx61_channels[] = { >>>> + KMX61_ACC_CHAN(X, KMX61_SCAN_ACC_X), >>>> + KMX61_ACC_CHAN(Y, KMX61_SCAN_ACC_Y), >>>> + KMX61_ACC_CHAN(Z, KMX61_SCAN_ACC_Z), >>>> + KMX61_MAG_CHAN(X, KMX61_SCAN_MAG_X), >>>> + KMX61_MAG_CHAN(Y, KMX61_SCAN_MAG_Y), >>>> + KMX61_MAG_CHAN(Z, KMX61_SCAN_MAG_Z), >>>> +}; >>>> + >>>> +static int kmx61_convert_freq_to_bit(int val, int val2) >>>> +{ >>>> + int i; >>>> + >>>> + for (i = 0; i < ARRAY_SIZE(kmx61_samp_freq_table); i++) >>>> + if (val == kmx61_samp_freq_table[i].val && >>>> + val2 == kmx61_samp_freq_table[i].val2) >>>> + return kmx61_samp_freq_table[i].odr_bits; >>>> + return -EINVAL; >>>> +} >>>> +/** >>> Like here, the first line of the following multiline comments have one asterisk too much. >> >> I think this is the convention, when adding doxygen style documentation: >> http://lxr.free-electrons.com/source/fs/eventpoll.c#L382 >> >>>> + * kmx61_set_mode() - set KMX61 device operating mode >>>> + * @data - kmx61 device private data pointer >>>> + * @mode - bitmask, indicating operating mode for @device >>>> + * @device - bitmask, indicating device for which @mode needs to be set >>>> + * @update - update stby bits stored in device's private @data >>>> + * >>>> + * For each sensor (accelerometer/magnetometer) there are two operating modes >>>> + * STANDBY and OPERATION. Neither accel nor magn can be disabled independently >>>> + * if they are both enabled. Internal sensors state is saved in acc_stby and >>>> + * mag_stby members of driver's private @data. >>>> + */ >>>> +static int kmx61_set_mode(struct kmx61_data *data, u8 mode, u8 device, >>>> + bool update) >>>> +{ >>>> + int ret; >>>> + int acc_stby = -1, mag_stby = -1; >>>> + >>>> + ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_STBY); >>>> + if (ret < 0) { >>>> + dev_err(&data->client->dev, "Error reading reg_stby\n"); >>>> + return ret; >>>> + } >>>> + if (device & KMX61_ACC) { >>>> + if (mode & KMX61_ACC_STBY_BIT) { >>>> + ret |= KMX61_ACC_STBY_BIT; >>>> + acc_stby = 1; >>>> + } else { >>>> + ret &= ~KMX61_ACC_STBY_BIT; >>>> + acc_stby = 0; >>>> + } >>>> + } >>>> + >>>> + if (device & KMX61_MAG) { >>>> + if (mode & KMX61_MAG_STBY_BIT) { >>>> + ret |= KMX61_MAG_STBY_BIT; >>>> + mag_stby = 1; >>>> + } else { >>>> + ret &= ~KMX61_MAG_STBY_BIT; >>>> + mag_stby = 0; >>>> + } >>>> + } >>>> + >>>> + ret = i2c_smbus_write_byte_data(data->client, KMX61_REG_STBY, ret); >>>> + if (ret < 0) { >>>> + dev_err(&data->client->dev, "Error writing reg_stby\n"); >>>> + return ret; >>>> + } >>>> + >>>> + if (acc_stby != -1 && update) >>>> + data->acc_stby = !!acc_stby; >>>> + if (mag_stby != -1 && update) >>>> + data->mag_stby = !!mag_stby; >>> Why is there a need for double negation? >> >> Correct. Now it doesn't make sense since data->acc_stby is u8. >> >> But, with your suggestion if I will use bool to represent data->acc_stby >> then I think the code should use double negation to make it clear >> that data->acc_stby is bool and acc_stby is int. >> > Well, if it makes you happy, then go ahead. My interpretation of a bool is, that an assignment of 0 becomes 0/false, and an assignment of anything else becomes 1/true. So, I wouldn't see a need here (especially since acc_stby/mag_stby were distinctly assigned either 0 or 1). All right. It makes sense. >>>> + >>>> + return ret; >>> Since no error occured until this point, just return 0. >> >> Ok. Will fix. >> >>>> +} >>>> + >>>> +static int kmx61_get_mode(struct kmx61_data *data, u8 *mode, u8 device) >>>> +{ >>>> + int ret; >>>> + >>>> + ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_STBY); >>>> + if (ret < 0) { >>>> + dev_err(&data->client->dev, "Error reading reg_stby\n"); >>>> + return ret; >>>> + } >>>> + *mode = 0; >>>> + >>>> + if (device & KMX61_ACC) { >>>> + if (ret & KMX61_ACC_STBY_BIT) >>>> + *mode |= KMX61_ACC_STBY_BIT; >>>> + else >>>> + *mode &= ~KMX61_ACC_STBY_BIT; >>> Simply: >>> *mode |= ret & KMX61_ACC_STBY_BIT; >> Ok. >> >>>> + } >>>> + >>>> + if (device & KMX61_MAG) { >>>> + if (ret & KMX61_MAG_STBY_BIT) >>>> + *mode |= KMX61_MAG_STBY_BIT; >>>> + else >>>> + *mode &= ~KMX61_MAG_STBY_BIT; >>> Same here: >> Ok. >> >>> *mode |= ret & KMX61_MAG_STBY_BIT; >>>> + } >>>> + >>>> + return 0; >>>> +} >>>> + >>>> +static int kmx61_set_odr(struct kmx61_data *data, int val, int val2, u8 device) >>>> +{ >>>> + int ret; >>>> + u8 mode; >>>> + int lodr_bits, odr_bits; >>>> + >>>> + ret = kmx61_get_mode(data, &mode, KMX61_ACC | KMX61_MAG); >>>> + if (ret < 0) >>>> + return ret; >>>> + >>>> + lodr_bits = kmx61_convert_freq_to_bit(val, val2); >>>> + if (lodr_bits < 0) >>>> + return lodr_bits; >>>> + >>>> + /* To change ODR, accel and magn must be in STDBY */ >>>> + ret = kmx61_set_mode(data, KMX61_ALL_STBY, KMX61_ACC | KMX61_MAG, >>>> + true); >>>> + if (ret < 0) >>>> + return ret; >>>> + >>>> + odr_bits = 0; >>>> + if (device & KMX61_ACC) >>>> + odr_bits |= lodr_bits; >>>> + if (device & KMX61_MAG) >>>> + odr_bits |= (lodr_bits << KMX61_MAG_ODR_SHIFT); >>> No need for parenthesis. >> ok. >> >>>> + >>>> + ret = i2c_smbus_write_byte_data(data->client, KMX61_REG_ODCNTL, >>>> + odr_bits); >>>> + if (ret < 0) >>>> + return ret; >>>> + >>>> + ret = kmx61_set_mode(data, mode, KMX61_ACC | KMX61_MAG, true); >>>> + if (ret < 0) >>>> + return ret; >>>> + >>>> + data->odr_bits = lodr_bits; >>>> + >>>> + return 0; >>>> +} >>>> + >>>> +static >>>> +int kmx61_get_odr(struct kmx61_data *data, int *val, int *val2, u8 device) >>> Usually wrap parameters? And don't put code on line with {. >> >> Will fix. >> >>>> +{ int i; >>>> + u8 lodr_bits; >>>> + >>>> + if (device & KMX61_ACC) >>>> + lodr_bits = (data->odr_bits >> KMX61_ACC_ODR_SHIFT) & >>>> + KMX61_ACC_ODR_MASK; >>> KMX61_ACC_ODR_SHIFT is just a placebo and not used in kmx61_set_odr. Choose one way and stay consistent. >> >> placebo is good. will fix kmx61_set_odr :) >> >>>> + else if (device & KMX61_MAG) >>>> + lodr_bits = (data->odr_bits >> KMX61_MAG_ODR_SHIFT) & >>>> + KMX61_MAG_ODR_MASK; >>>> + else >>>> + return -EINVAL; >>>> + >>>> + for (i = 0; i < ARRAY_SIZE(kmx61_samp_freq_table); i++) >>>> + if (lodr_bits == kmx61_samp_freq_table[i].odr_bits) { >>>> + *val = kmx61_samp_freq_table[i].val; >>>> + *val2 = kmx61_samp_freq_table[i].val2; >>>> + return 0; >>> return IIO_VAL_INT_PLUS_MICRO allows you to faciliate _read_raw a bit to just return ret there. >> >> Hmm, If you don't mind I want to keep this as it is, just to >> be consistent with the rest of the functions. The convention >> used is to return 0 in case of success. >> > Up to you. Though kmx61_read_raw() would be an example of a function that doesn't follow this convention ;-) And there is no real benefit of checking an error code there, which is passed up anyway. >>>> + } >>>> + return -EINVAL; >>>> +} >>>> + >>>> +static int kmx61_set_range(struct kmx61_data *data, int range) >>>> +{ >>>> + int ret; >>>> + >>>> + ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_CTRL1); >>>> + if (ret < 0) { >>>> + dev_err(&data->client->dev, "Error reading reg_ctrl1\n"); >>>> + return ret; >>>> + } >>>> + >>>> + ret &= ~(KMX61_REG_CTRL1_GSEL0_MASK | KMX61_REG_CTRL1_GSEL1_MASK); >>>> + ret |= kmx61_scale_table[range].gsel0 << KMX61_REG_CTRL1_GSEL0_SHIFT; >>>> + ret |= kmx61_scale_table[range].gsel1 << KMX61_REG_CTRL1_GSEL1_SHIFT; >>>> + >>>> + ret = i2c_smbus_write_byte_data(data->client, KMX61_REG_CTRL1, ret); >>>> + if (ret < 0) { >>>> + dev_err(&data->client->dev, "Error writing reg_ctrl1\n"); >>>> + return ret; >>>> + } >>>> + >>>> + data->range = range; >>>> + >>>> + return 0; >>>> +} >>>> + >>>> +static int kmx61_set_scale(struct kmx61_data *data, int uscale) >>>> +{ >>>> + int ret, i; >>>> + u8 mode; >>>> + >>>> + for (i = 0; i < ARRAY_SIZE(kmx61_scale_table); i++) { >>>> + if (kmx61_scale_table[i].uscale == uscale) { >>>> + ret = kmx61_get_mode(data, &mode, >>>> + KMX61_ACC | KMX61_MAG); >>>> + if (ret < 0) >>>> + return ret; >>>> + >>>> + ret = kmx61_set_mode(data, KMX61_ALL_STBY, >>>> + KMX61_ACC | KMX61_MAG, true); >>>> + if (ret < 0) >>>> + return ret; >>>> + >>>> + ret = kmx61_set_range(data, i); >>>> + if (ret < 0) >>>> + return ret; >>>> + >>>> + return kmx61_set_mode(data, mode, >>>> + KMX61_ACC | KMX61_MAG, true); >>>> + } >>>> + } >>>> + return -EINVAL; >>>> +} >>>> + >>>> +static int kmx61_chip_init(struct kmx61_data *data) >>>> +{ >>>> + int ret; >>>> + >>>> + ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_WHO_AM_I); >>>> + if (ret < 0) { >>>> + dev_err(&data->client->dev, "Error reading who_am_i\n"); >>>> + return ret; >>>> + } >>>> + >>>> + if (ret != KMX61_CHIP_ID) { >>>> + dev_err(&data->client->dev, >>>> + "Wrong chip id, got %x expected %x\n", >>>> + ret, KMX61_CHIP_ID); >>>> + return -EINVAL; >>>> + } >>>> + >>>> + /* set accel 12bit, 4g range */ >>>> + ret = kmx61_set_range(data, KMX61_RANGE_4G); >>>> + if (ret < 0) >>>> + return ret; >>>> + >>>> + /* set acc/magn to OPERATION mode */ >>>> + ret = kmx61_set_mode(data, 0, KMX61_ACC | KMX61_MAG, true); >>> Just return kmx61_set_mode(data, 0, KMX61_ACC | KMX61_MAG, true); >> >> Ok. >> >>>> + if (ret < 0) >>>> + return ret; >>>> + >>>> + return 0; >>>> +} >>>> +/** >>>> + * kmx61_set_power_state() - set power state for kmx61 @device >>>> + * @data - kmx61 device private pointer >>>> + * @on - power state to be set for @device >>>> + * @device - bitmask indicating device for which @on state needs to be set >>>> + * >>>> + * Notice that when ACC power state needs to be set to ON and MAG is in >>>> + * OPERATION then we know that kmx61_runtime_resume was already called >>>> + * so we must set ACC OPERATION mode here. The same happens when MAG power >>>> + * state needs to be set to ON and ACC is in OPERATION. >>>> + */ >>>> +static int kmx61_set_power_state(struct kmx61_data *data, bool on, u8 device) >>>> +{ >>>> +#ifdef CONFIG_PM_RUNTIME >>>> + int ret; >>>> + >>>> + if (device & KMX61_ACC) { >>>> + if (on && !data->acc_ps && !data->mag_stby) >>>> + kmx61_set_mode(data, 0, KMX61_ACC, true); >>>> + data->acc_ps = on; >>>> + } >>>> + if (device & KMX61_MAG) { >>>> + if (on && !data->mag_ps && !data->acc_stby) >>>> + kmx61_set_mode(data, 0, KMX61_MAG, true); >>>> + data->mag_ps = on; >>>> + } >>>> + >>>> + if (on) { >>>> + ret = pm_runtime_get_sync(&data->client->dev); >>>> + } else { >>>> + pm_runtime_mark_last_busy(&data->client->dev); >>>> + ret = pm_runtime_put_autosuspend(&data->client->dev); >>>> + } >>>> + if (ret < 0) { >>>> + dev_err(&data->client->dev, >>>> + "Failed: kmx61_set_power_state for %d, ret %d\n", >>>> + on, ret); >>>> + return ret; >>>> + } >>>> +#endif >>>> + return 0; >>>> +} >>>> + >>>> +static int kmx61_read_measurement(struct kmx61_data *data, int base, int offset) >>> u8 base, u8 offset? >> >> Correct. >> >>>> +{ >>>> + int ret; >>>> + u8 reg = base + offset * 2; >>>> + >>>> + ret = i2c_smbus_read_word_data(data->client, reg); >>>> + if (ret < 0) { >>>> + dev_err(&data->client->dev, "failed to read reg at %x\n", reg); >>>> + return ret; >>> This return is unnecessary. >> >> Ok. >> >>>> + } >>>> + >>>> + return ret; >>>> +} >>>> + >>>> +static int kmx61_read_raw(struct iio_dev *indio_dev, >>>> + struct iio_chan_spec const *chan, int *val, >>>> + int *val2, long mask) >>> Indentation of the parameters is a bit too high. >> >> Ok, will fix. >> >>>> +{ >>>> + struct kmx61_data *data = iio_priv(indio_dev); >>>> + int ret; >>>> + u8 base_reg; >>>> + >>>> + switch (mask) { >>>> + case IIO_CHAN_INFO_RAW: >>>> + switch (chan->type) { >>>> + case IIO_ACCEL: >>>> + case IIO_MAGN: >>>> + base_reg = KMX61_ACC_XOUT_L; >>>> + break; >>>> + default: >>>> + return -EINVAL; >>>> + } >>>> + mutex_lock(&data->lock); >>>> + >>>> + kmx61_set_power_state(data, true, chan->address); >>>> + ret = kmx61_read_measurement(data, base_reg, chan->scan_index); >>>> + if (ret < 0) { >>>> + kmx61_set_power_state(data, false, chan->address); >>>> + mutex_unlock(&data->lock); >>>> + return ret; >>>> + } >>>> + *val = sign_extend32(ret >> chan->scan_type.shift, >>>> + chan->scan_type.realbits - 1); >>>> + kmx61_set_power_state(data, false, chan->address); >>>> + >>>> + mutex_unlock(&data->lock); >>>> + return IIO_VAL_INT; >>>> + case IIO_CHAN_INFO_SCALE: >>>> + switch (chan->type) { >>>> + case IIO_ACCEL: >>>> + *val = 0; >>>> + *val2 = kmx61_scale_table[data->range].uscale; >>>> + return IIO_VAL_INT_PLUS_MICRO; >>>> + case IIO_MAGN: >>>> + /* 14 bits res, 1465 microGauss per magn count */ >>>> + *val = 0; >>>> + *val2 = 1465; >>>> + return IIO_VAL_INT_PLUS_MICRO; >>>> + default: >>>> + return -EINVAL; >>>> + } >>>> + case IIO_CHAN_INFO_SAMP_FREQ: >>>> + if (chan->type != IIO_ACCEL && chan->type != IIO_MAGN) >>>> + return -EINVAL; >>>> + >>>> + mutex_lock(&data->lock); >>>> + ret = kmx61_get_odr(data, val, val2, chan->address); >>>> + mutex_unlock(&data->lock); >>> Could be just return ret here, if kmx61_get_odr() returns IIO_VAL_INT_PLUS_MICRO on success and -EINVAL on error. >> >> As explained above, I prefer not to do this. More than that, I can't do ret here >> because the data->lock is held. >> > Well, I actually intended to have an unconditional "return ret;" right after the mutex_unlock. But up to you. I also see a good point to make it obvious here, that the return value is IIO_VAL_INT_PLUS_MICRO. So, up to you. >>>> + if (ret) >>>> + return -EINVAL; >>>> + return IIO_VAL_INT_PLUS_MICRO; >>>> + } >>>> + return -EINVAL; >>>> +} >>>> + >>>> +static int kmx61_write_raw(struct iio_dev *indio_dev, >>>> + struct iio_chan_spec const *chan, int val, >>>> + int val2, long mask) >>> Indentation of parameters is too high. >> Ok. >>>> +{ >>>> + struct kmx61_data *data = iio_priv(indio_dev); >>>> + int ret; >>>> + >>>> + switch (mask) { >>>> + case IIO_CHAN_INFO_SAMP_FREQ: >>>> + if (chan->type != IIO_ACCEL && chan->type != IIO_MAGN) >>>> + return -EINVAL; >>>> + >>>> + mutex_lock(&data->lock); >>>> + ret = kmx61_set_odr(data, val, val2, chan->address); >>>> + mutex_unlock(&data->lock); >>>> + return ret; >>>> + case IIO_CHAN_INFO_SCALE: >>>> + switch (chan->type) { >>>> + case IIO_ACCEL: >>>> + if (val != 0) >>>> + return -EINVAL; >>>> + mutex_lock(&data->lock); >>>> + ret = kmx61_set_scale(data, val2); >>>> + mutex_unlock(&data->lock); >>>> + return ret; >>>> + default: >>>> + return -EINVAL; >>>> + } >>>> + return ret; >>> This won't be reached (if so, ret would not be initialized). >>>> + default: >>>> + return -EINVAL; >>>> + } >>>> + return ret; >>> Same here. >> >> I know. Would initializing ret with 0 will be enough? > Since the switch already catches all cases and returns, there is no need for return ret, here. But if you prefer to have a return at the end of the function, you could drop the default case, or leave it empty, or just put a break in there - and return -EINVAL at the end. Ok. I will remove the the unnecessary return. >> >>>> +} >>>> + >>>> +static const struct iio_info kmx61_info = { >>>> + .driver_module = THIS_MODULE, >>>> + .read_raw = kmx61_read_raw, >>>> + .write_raw = kmx61_write_raw, >>>> + .attrs = &kmx61_attribute_group, >>>> +}; >>>> + >>>> +static int kmx61_probe(struct i2c_client *client, >>>> + const struct i2c_device_id *id) >>>> +{ >>>> + struct kmx61_data *data; >>>> + struct iio_dev *indio_dev; >>>> + int ret; >>>> + const char *name = NULL; >>>> + >>>> + indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); >>>> + if (!indio_dev) >>>> + return -ENOMEM; >>>> + >>>> + data = iio_priv(indio_dev); >>>> + i2c_set_clientdata(client, indio_dev); >>>> + data->client = client; >>>> + >>>> + if (id) >>>> + name = id->name; >>>> + >>>> + indio_dev->dev.parent = &client->dev; >>>> + indio_dev->channels = kmx61_channels; >>>> + indio_dev->num_channels = ARRAY_SIZE(kmx61_channels); >>>> + indio_dev->name = name; >>>> + indio_dev->modes = INDIO_DIRECT_MODE; >>>> + indio_dev->info = &kmx61_info; >>>> + >>>> + mutex_init(&data->lock); >>>> + >>>> + ret = kmx61_chip_init(data); >>>> + if (ret < 0) >>>> + return ret; >>>> + >>>> + ret = iio_device_register(indio_dev); >>>> + if (ret < 0) { >>>> + dev_err(&client->dev, "Failed to register iio device\n"); >>>> + goto err_iio_device_register; >>>> + } >>>> + >>>> + ret = pm_runtime_set_active(&client->dev); >>>> + if (ret < 0) >>>> + goto err_pm_runtime_set_active; >>>> + >>>> + pm_runtime_enable(&client->dev); >>>> + pm_runtime_set_autosuspend_delay(&client->dev, KMX61_SLEEP_DELAY_MS); >>>> + pm_runtime_use_autosuspend(&client->dev); >>>> + >>>> + return 0; >>>> + >>>> +err_pm_runtime_set_active: >>>> + iio_device_unregister(indio_dev); >>>> +err_iio_device_register: >>>> + kmx61_set_mode(data, KMX61_ALL_STBY, KMX61_ACC | KMX61_MAG, true); >>>> + return ret; >>>> +} >>>> + >>>> +static int kmx61_remove(struct i2c_client *client) >>>> +{ >>>> + struct iio_dev *indio_dev = i2c_get_clientdata(client); >>>> + struct kmx61_data *data = iio_priv(indio_dev); >>>> + int ret; >>>> + >>>> + pm_runtime_disable(&client->dev); >>>> + pm_runtime_set_suspended(&client->dev); >>>> + pm_runtime_put_noidle(&client->dev); >>>> + >>>> + iio_device_unregister(indio_dev); >>>> + >>>> + mutex_lock(&data->lock); >>>> + ret = kmx61_set_mode(data, KMX61_ALL_STBY, KMX61_ACC | KMX61_MAG, true); >>>> + mutex_unlock(&data->lock); >>>> + >>>> + return ret; >>>> +} >>>> + >>>> +#ifdef CONFIG_PM_SLEEP >>>> +static int kmx61_suspend(struct device *dev) >>>> +{ >>>> + struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev)); >>>> + struct kmx61_data *data = iio_priv(indio_dev); >>>> + int ret; >>>> + >>>> + mutex_lock(&data->lock); >>>> + ret = kmx61_set_mode(data, KMX61_ALL_STBY, KMX61_ACC | KMX61_MAG, >>>> + false); >>>> + mutex_unlock(&data->lock); >>>> + >>>> + return ret; >>>> +} >>>> + >>>> +static int kmx61_resume(struct device *dev) >>>> +{ >>>> + struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev)); >>>> + struct kmx61_data *data = iio_priv(indio_dev); >>>> + u8 stby = 0; >>>> + >>>> + if (data->acc_stby) >>>> + stby |= KMX61_ACC_STBY_BIT; >>>> + if (data->mag_stby) >>>> + stby |= KMX61_MAG_STBY_BIT; >>>> + >>>> + return kmx61_set_mode(data, stby, KMX61_ACC | KMX61_MAG, true); >>>> +} >>>> +#endif >>>> + >>>> +#ifdef CONFIG_PM_RUNTIME >>>> +static int kmx61_runtime_suspend(struct device *dev) >>>> +{ >>>> + struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev)); >>>> + struct kmx61_data *data = iio_priv(indio_dev); >>>> + int ret; >>>> + >>>> + mutex_lock(&data->lock); >>>> + ret = kmx61_set_mode(data, KMX61_ALL_STBY, KMX61_ACC | KMX61_MAG, true); >>>> + mutex_unlock(&data->lock); >>>> + >>>> + return ret; >>>> +} >>>> + >>>> +static int kmx61_runtime_resume(struct device *dev) >>>> +{ >>>> + struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev)); >>>> + struct kmx61_data *data = iio_priv(indio_dev); >>>> + u8 stby = 0; >>>> + >>>> + if (!data->acc_ps) >>>> + stby |= KMX61_ACC_STBY_BIT; >>>> + if (!data->mag_ps) >>>> + stby |= KMX61_MAG_STBY_BIT; >>>> + >>>> + return kmx61_set_mode(data, stby, KMX61_ACC | KMX61_MAG, true); >>>> +} >>>> +#endif >>>> + >>>> +static const struct dev_pm_ops kmx61_pm_ops = { >>>> + SET_SYSTEM_SLEEP_PM_OPS(kmx61_suspend, kmx61_resume) >>>> + SET_RUNTIME_PM_OPS(kmx61_runtime_suspend, kmx61_runtime_resume, NULL) >>>> +}; >>>> + >>>> +static const struct i2c_device_id kmx61_id[] = { >>>> + {"kmx611021", 0}, >>>> + {} >>>> +}; >>>> + >>>> +MODULE_DEVICE_TABLE(i2c, kmx61_id); >>>> + >>>> +static struct i2c_driver kmx61_driver = { >>>> + .driver = { >>>> + .name = KMX61_DRV_NAME, >>>> + .pm = &kmx61_pm_ops, >>>> + }, >>>> + .probe = kmx61_probe, >>>> + .remove = kmx61_remove, >>>> + .id_table = kmx61_id, >>>> +}; >>>> + >>>> +module_i2c_driver(kmx61_driver); >>>> + >>>> +MODULE_AUTHOR("Daniel Baluta "); >>>> +MODULE_DESCRIPTION("KMX61 accelerometer/magnetometer driver"); >>>> +MODULE_LICENSE("GPL v2"); >> >> Hartmut, thanks a lot for your reviews. I will send a patch series >> with these cleanups together with changes for ACPI, buffer and trigger >> support. > Don't know if Jonathan would like to see it smashed together, already. > Take care By together I mean separate patches in the same patch set. I will take Daniel. -- 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/