From: Laurentiu Palcu <laurentiu.palcu@intel.com>
To: Peter Meerwald <pmeerw@pmeerw.net>
Cc: Jonathan Cameron <jic23@kernel.org>,
Hartmut Knaack <knaack.h@gmx.de>,
Lars-Peter Clausen <lars@metafoo.de>,
Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>,
linux-iio@vger.kernel.org
Subject: Re: [PATCH v3 3/3] iio: accel: BMC150: add support for other Bosch chips
Date: Mon, 1 Sep 2014 16:03:54 +0300 [thread overview]
Message-ID: <20140901130354.GD12606@lpalcu-linux> (raw)
In-Reply-To: <20140901125509.GC12606@lpalcu-linux>
On Mon, Sep 01, 2014 at 03:55:09PM +0300, Laurentiu Palcu wrote:
> Hi Peter,
>
> On Mon, Sep 01, 2014 at 01:02:02PM +0200, Peter Meerwald wrote:
> >
> > > The following chips are either similar or have only the resolution
> > > different. Hence, change this driver to support these chips too:
> > >
> > > BMI055 - combo chip (accelerometer part is identical to BMC150's)
> > > BMA255 - identical to BMC150's accelerometer
> > > BMA222E - 8 bit resolution
> > > BMA250E - 10 bit resolution
> > > BMA280 - 14 bit resolution
> > >
> > > Additionally:
> > > * add bmc150_accel_match_acpi_device() function to check that the device
> > > has been enumerated through ACPI;
> > > * rename bmc150_accel_acpi_gpio_probe() to bmc150_accel_gpio_probe()
> > > since the ACPI matching has been moved to the new function. Also, this
> > > will allow for the GPIO matching to be done against a device tree too, not only
> > > ACPI tree;
> >
> > similar comment below
> >
> > > Signed-off-by: Laurentiu Palcu <laurentiu.palcu@intel.com>
> > > ---
> > >
> > > Changes in v3:
> > > * remove the chip id macros since they were not used anywhere else and put the id
> > > values directly in the chip info table;
> > > * fix the unnecessary casting from const char * to char * and back;
> > >
> > > Thank you Jonathan for the reviews,
> > > laurentiu
> > >
> > > drivers/iio/accel/bmc150-accel.c | 225 +++++++++++++++++++++++++++++----------
> > > 1 file changed, 171 insertions(+), 54 deletions(-)
> > >
> > > diff --git a/drivers/iio/accel/bmc150-accel.c b/drivers/iio/accel/bmc150-accel.c
> > > index 0e6566a..72f4250 100644
> > > --- a/drivers/iio/accel/bmc150-accel.c
> > > +++ b/drivers/iio/accel/bmc150-accel.c
> > > @@ -1,5 +1,12 @@
> > > /*
> > > - * BMC150 3-axis accelerometer driver
> > > + * 3-axis accelerometer driver supporting following Bosch-Sensortec chips:
> > > + * - BMC150
> > > + * - BMI055
> > > + * - BMA255
> > > + * - BMA250E
> > > + * - BMA222E
> > > + * - BMA280
> > > + *
> > > * Copyright (c) 2014, Intel Corporation.
> > > *
> > > * This program is free software; you can redistribute it and/or modify it
> > > @@ -34,7 +41,6 @@
> > > #define BMC150_ACCEL_GPIO_NAME "bmc150_accel_int"
> > >
> > > #define BMC150_ACCEL_REG_CHIP_ID 0x00
> > > -#define BMC150_ACCEL_CHIP_ID_VAL 0xFA
> > >
> > > #define BMC150_ACCEL_REG_INT_STATUS_2 0x0B
> > > #define BMC150_ACCEL_ANY_MOTION_MASK 0x07
> > > @@ -126,6 +132,18 @@ enum bmc150_power_modes {
> > > BMC150_ACCEL_SLEEP_MODE_SUSPEND = 0x04,
> > > };
> > >
> > > +struct bmc150_scale_info {
> > > + int scale;
> > > + int range;
> >
> > range could be u8 and probably named reg_range to have the same naming
> > convention for these mappings (see below, reg_value)
> I'm not keen on changing unrelated things in the same patch, since this
> declaration existed in the original patch and I only moved it several
> line up, but I agree that the naming should be consistent.
>
> However, I would rename it 'reg_value' too, as it's done below, not
> 'reg_range', because it represents the value we write in the register for
> a certain scale.
My bad. I spoke too fast... :/ I guess reg_range is fine here.
laurentiu
>
> I'll send a v4 with this renaming and, also, change it from int to u8.
>
> laurentiu
>
> >
> > > +};
> > > +
> > > +struct bmc150_accel_chip_info {
> > > + u8 chip_id;
> > > + const struct iio_chan_spec *channels;
> > > + int num_channels;
> > > + const struct bmc150_scale_info scale_table[4];
> > > +};
> > > +
> > > struct bmc150_accel_data {
> > > struct i2c_client *client;
> > > struct iio_trigger *dready_trig;
> > > @@ -140,6 +158,7 @@ struct bmc150_accel_data {
> > > bool dready_trigger_on;
> > > bool motion_trigger_on;
> > > int64_t timestamp;
> > > + const struct bmc150_accel_chip_info *chip_info;
> > > };
> > >
> > > static const struct {
> > > @@ -168,14 +187,6 @@ static const struct {
> > > {0x0F, 1} };
> > >
> > > static const struct {
> > > - int scale;
> > > - int range;
> > > -} bmc150_accel_scale_table[] = { {9610, BMC150_ACCEL_DEF_RANGE_2G},
> > > - {19122, BMC150_ACCEL_DEF_RANGE_4G},
> > > - {38344, BMC150_ACCEL_DEF_RANGE_8G},
> > > - {76590, BMC150_ACCEL_DEF_RANGE_16G} };
> > > -
> > > -static const struct {
> > > int sleep_dur;
> > > int reg_value;
> >
> > reg_value could be u8
> >
> > > } bmc150_accel_sleep_value_table[] = { {0, 0},
> > > @@ -267,7 +278,7 @@ static int bmc150_accel_chip_init(struct bmc150_accel_data *data)
> > > }
> > >
> > > dev_dbg(&data->client->dev, "Chip Id %x\n", ret);
> > > - if (ret != BMC150_ACCEL_CHIP_ID_VAL) {
> > > + if (ret != data->chip_info->chip_id) {
> > > dev_err(&data->client->dev, "Invalid chip %x\n", ret);
> > > return -ENODEV;
> > > }
> > > @@ -541,19 +552,19 @@ static int bmc150_accel_set_scale(struct bmc150_accel_data *data, int val)
> > > {
> > > int ret, i;
> > >
> > > - for (i = 0; i < ARRAY_SIZE(bmc150_accel_scale_table); ++i) {
> > > - if (bmc150_accel_scale_table[i].scale == val) {
> > > + for (i = 0; i < ARRAY_SIZE(data->chip_info->scale_table); ++i) {
> > > + if (data->chip_info->scale_table[i].scale == val) {
> > > ret = i2c_smbus_write_byte_data(
> > > data->client,
> > > BMC150_ACCEL_REG_PMU_RANGE,
> > > - bmc150_accel_scale_table[i].range);
> > > + data->chip_info->scale_table[i].range);
> > > if (ret < 0) {
> > > dev_err(&data->client->dev,
> > > "Error writing pmu_range\n");
> > > return ret;
> > > }
> > >
> > > - data->range = bmc150_accel_scale_table[i].range;
> > > + data->range = data->chip_info->scale_table[i].range;
> > > return 0;
> > > }
> > > }
> > > @@ -580,10 +591,12 @@ static int bmc150_accel_get_temp(struct bmc150_accel_data *data, int *val)
> > > return IIO_VAL_INT;
> > > }
> > >
> > > -static int bmc150_accel_get_axis(struct bmc150_accel_data *data, int axis,
> > > +static int bmc150_accel_get_axis(struct bmc150_accel_data *data,
> > > + struct iio_chan_spec const *chan,
> > > int *val)
> > > {
> > > int ret;
> > > + int axis = chan->scan_index;
> > >
> > > mutex_lock(&data->mutex);
> > > ret = bmc150_accel_set_power_state(data, true);
> > > @@ -600,7 +613,8 @@ static int bmc150_accel_get_axis(struct bmc150_accel_data *data, int axis,
> > > mutex_unlock(&data->mutex);
> > > return ret;
> > > }
> > > - *val = sign_extend32(ret >> 4, 11);
> > > + *val = sign_extend32(ret >> chan->scan_type.shift,
> > > + chan->scan_type.realbits - 1);
> > > ret = bmc150_accel_set_power_state(data, false);
> > > mutex_unlock(&data->mutex);
> > > if (ret < 0)
> > > @@ -625,9 +639,7 @@ static int bmc150_accel_read_raw(struct iio_dev *indio_dev,
> > > if (iio_buffer_enabled(indio_dev))
> > > return -EBUSY;
> > > else
> > > - return bmc150_accel_get_axis(data,
> > > - chan->scan_index,
> > > - val);
> > > + return bmc150_accel_get_axis(data, chan, val);
> > > default:
> > > return -EINVAL;
> > > }
> > > @@ -647,12 +659,13 @@ static int bmc150_accel_read_raw(struct iio_dev *indio_dev,
> > > {
> > > int i;
> > >
> > > - for (i = 0; i < ARRAY_SIZE(bmc150_accel_scale_table);
> > > - ++i) {
> > > - if (bmc150_accel_scale_table[i].range ==
> > > + for (i = 0;
> > > + i < ARRAY_SIZE(data->chip_info->scale_table);
> > > + ++i) {
> > > + if (data->chip_info->scale_table[i].range ==
> > > data->range) {
> > > *val2 =
> > > - bmc150_accel_scale_table[i].scale;
> > > + data->chip_info->scale_table[i].scale;
> > > return IIO_VAL_INT_PLUS_MICRO;
> > > }
> > > }
> > > @@ -840,7 +853,7 @@ static const struct iio_event_spec bmc150_accel_event = {
> > > BIT(IIO_EV_INFO_PERIOD)
> > > };
> > >
> > > -#define BMC150_ACCEL_CHANNEL(_axis) { \
> > > +#define BMC150_ACCEL_CHANNEL(_axis, bits) { \
> > > .type = IIO_ACCEL, \
> > > .modified = 1, \
> > > .channel2 = IIO_MOD_##_axis, \
> > > @@ -850,26 +863,101 @@ static const struct iio_event_spec bmc150_accel_event = {
> > > .scan_index = AXIS_##_axis, \
> > > .scan_type = { \
> > > .sign = 's', \
> > > - .realbits = 12, \
> > > + .realbits = (bits), \
> > > .storagebits = 16, \
> > > - .shift = 4, \
> > > + .shift = 16 - (bits), \
> > > }, \
> > > .event_spec = &bmc150_accel_event, \
> > > .num_event_specs = 1 \
> > > }
> > >
> > > -static const struct iio_chan_spec bmc150_accel_channels[] = {
> > > - {
> > > - .type = IIO_TEMP,
> > > - .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> > > - BIT(IIO_CHAN_INFO_SCALE) |
> > > - BIT(IIO_CHAN_INFO_OFFSET),
> > > - .scan_index = -1,
> > > +#define BMC150_ACCEL_CHANNELS(bits) { \
> > > + { \
> > > + .type = IIO_TEMP, \
> > > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
> > > + BIT(IIO_CHAN_INFO_SCALE) | \
> > > + BIT(IIO_CHAN_INFO_OFFSET), \
> > > + .scan_index = -1, \
> > > + }, \
> > > + BMC150_ACCEL_CHANNEL(X, bits), \
> > > + BMC150_ACCEL_CHANNEL(Y, bits), \
> > > + BMC150_ACCEL_CHANNEL(Z, bits), \
> > > + IIO_CHAN_SOFT_TIMESTAMP(3), \
> > > +}
> > > +
> > > +static const struct iio_chan_spec bma222e_accel_channels[] =
> > > + BMC150_ACCEL_CHANNELS(8);
> > > +static const struct iio_chan_spec bma250e_accel_channels[] =
> > > + BMC150_ACCEL_CHANNELS(10);
> > > +static const struct iio_chan_spec bmc150_accel_channels[] =
> > > + BMC150_ACCEL_CHANNELS(12);
> > > +static const struct iio_chan_spec bma280_accel_channels[] =
> > > + BMC150_ACCEL_CHANNELS(14);
> > > +
> > > +enum {
> > > + bmc150,
> > > + bmi055,
> > > + bma255,
> > > + bma250e,
> > > + bma222e,
> > > + bma280,
> > > +};
> > > +
> > > +static const struct bmc150_accel_chip_info bmc150_accel_chip_info_tbl[] = {
> > > + [bmc150] = {
> > > + .chip_id = 0xFA,
> > > + .channels = bmc150_accel_channels,
> > > + .num_channels = ARRAY_SIZE(bmc150_accel_channels),
> > > + .scale_table = { {9610, BMC150_ACCEL_DEF_RANGE_2G},
> > > + {19122, BMC150_ACCEL_DEF_RANGE_4G},
> > > + {38344, BMC150_ACCEL_DEF_RANGE_8G},
> > > + {76590, BMC150_ACCEL_DEF_RANGE_16G} },
> > > + },
> > > + [bmi055] = {
> > > + .chip_id = 0xFA,
> > > + .channels = bmc150_accel_channels,
> > > + .num_channels = ARRAY_SIZE(bmc150_accel_channels),
> > > + .scale_table = { {9610, BMC150_ACCEL_DEF_RANGE_2G},
> > > + {19122, BMC150_ACCEL_DEF_RANGE_4G},
> > > + {38344, BMC150_ACCEL_DEF_RANGE_8G},
> > > + {76590, BMC150_ACCEL_DEF_RANGE_16G} },
> > > + },
> > > + [bma255] = {
> > > + .chip_id = 0xFA,
> > > + .channels = bmc150_accel_channels,
> > > + .num_channels = ARRAY_SIZE(bmc150_accel_channels),
> > > + .scale_table = { {9610, BMC150_ACCEL_DEF_RANGE_2G},
> > > + {19122, BMC150_ACCEL_DEF_RANGE_4G},
> > > + {38344, BMC150_ACCEL_DEF_RANGE_8G},
> > > + {76590, BMC150_ACCEL_DEF_RANGE_16G} },
> > > + },
> > > + [bma250e] = {
> > > + .chip_id = 0xF9,
> > > + .channels = bma250e_accel_channels,
> > > + .num_channels = ARRAY_SIZE(bma250e_accel_channels),
> > > + .scale_table = { {38344, BMC150_ACCEL_DEF_RANGE_2G},
> > > + {76590, BMC150_ACCEL_DEF_RANGE_4G},
> > > + {153277, BMC150_ACCEL_DEF_RANGE_8G},
> > > + {306457, BMC150_ACCEL_DEF_RANGE_16G} },
> > > + },
> > > + [bma222e] = {
> > > + .chip_id = 0xF8,
> > > + .channels = bma222e_accel_channels,
> > > + .num_channels = ARRAY_SIZE(bma222e_accel_channels),
> > > + .scale_table = { {153277, BMC150_ACCEL_DEF_RANGE_2G},
> > > + {306457, BMC150_ACCEL_DEF_RANGE_4G},
> > > + {612915, BMC150_ACCEL_DEF_RANGE_8G},
> > > + {1225831, BMC150_ACCEL_DEF_RANGE_16G} },
> > > + },
> > > + [bma280] = {
> > > + .chip_id = 0xFB,
> > > + .channels = bma280_accel_channels,
> > > + .num_channels = ARRAY_SIZE(bma280_accel_channels),
> > > + .scale_table = { {2392, BMC150_ACCEL_DEF_RANGE_2G},
> > > + {4785, BMC150_ACCEL_DEF_RANGE_4G},
> > > + {9581, BMC150_ACCEL_DEF_RANGE_8G},
> > > + {19152, BMC150_ACCEL_DEF_RANGE_16G} },
> > > },
> > > - BMC150_ACCEL_CHANNEL(X),
> > > - BMC150_ACCEL_CHANNEL(Y),
> > > - BMC150_ACCEL_CHANNEL(Z),
> > > - IIO_CHAN_SOFT_TIMESTAMP(3),
> > > };
> > >
> > > static const struct iio_info bmc150_accel_info = {
> > > @@ -1040,10 +1128,23 @@ static irqreturn_t bmc150_accel_data_rdy_trig_poll(int irq, void *private)
> > > return IRQ_HANDLED;
> > > }
> > >
> > > -static int bmc150_accel_acpi_gpio_probe(struct i2c_client *client,
> > > - struct bmc150_accel_data *data)
> > > +static const char *bmc150_accel_match_acpi_device(struct device *dev, int *data)
> > > {
> > > const struct acpi_device_id *id;
> > > +
> > > + id = acpi_match_device(dev->driver->acpi_match_table, dev);
> > > +
> > > + if (!id)
> > > + return NULL;
> > > +
> > > + *data = (int) id->driver_data;
> > > +
> > > + return dev_name(dev);
> > > +}
> > > +
> > > +static int bmc150_accel_gpio_probe(struct i2c_client *client,
> > > + struct bmc150_accel_data *data)
> > > +{
> > > struct device *dev;
> > > struct gpio_desc *gpio;
> > > int ret;
> > > @@ -1052,17 +1153,11 @@ static int bmc150_accel_acpi_gpio_probe(struct i2c_client *client,
> > > return -EINVAL;
> > >
> > > dev = &client->dev;
> > > - if (!ACPI_HANDLE(dev))
> > > - return -ENODEV;
> > > -
> > > - id = acpi_match_device(dev->driver->acpi_match_table, dev);
> > > - if (!id)
> > > - return -ENODEV;
> > >
> > > /* data ready gpio interrupt pin */
> > > gpio = devm_gpiod_get_index(dev, BMC150_ACCEL_GPIO_NAME, 0);
> > > if (IS_ERR(gpio)) {
> > > - dev_err(dev, "Failed: acpi gpio get index\n");
> > > + dev_err(dev, "Failed: gpio get index\n");
> > > return PTR_ERR(gpio);
> > > }
> > >
> > > @@ -1083,6 +1178,8 @@ static int bmc150_accel_probe(struct i2c_client *client,
> > > struct bmc150_accel_data *data;
> > > struct iio_dev *indio_dev;
> > > int ret;
> > > + const char *name = NULL;
> > > + int chip_id = 0;
> > >
> > > indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
> > > if (!indio_dev)
> > > @@ -1092,6 +1189,16 @@ static int bmc150_accel_probe(struct i2c_client *client,
> > > i2c_set_clientdata(client, indio_dev);
> > > data->client = client;
> > >
> > > + if (id) {
> > > + name = id->name;
> > > + chip_id = id->driver_data;
> > > + }
> > > +
> > > + if (ACPI_HANDLE(&client->dev))
> > > + name = bmc150_accel_match_acpi_device(&client->dev, &chip_id);
> > > +
> > > + data->chip_info = &bmc150_accel_chip_info_tbl[chip_id];
> > > +
> > > ret = bmc150_accel_chip_init(data);
> > > if (ret < 0)
> > > return ret;
> > > @@ -1099,14 +1206,14 @@ static int bmc150_accel_probe(struct i2c_client *client,
> > > mutex_init(&data->mutex);
> > >
> > > indio_dev->dev.parent = &client->dev;
> > > - indio_dev->channels = bmc150_accel_channels;
> > > - indio_dev->num_channels = ARRAY_SIZE(bmc150_accel_channels);
> > > - indio_dev->name = BMC150_ACCEL_DRV_NAME;
> > > + indio_dev->channels = data->chip_info->channels;
> > > + indio_dev->num_channels = data->chip_info->num_channels;
> > > + indio_dev->name = name;
> > > indio_dev->modes = INDIO_DIRECT_MODE;
> > > indio_dev->info = &bmc150_accel_info;
> > >
> > > if (client->irq < 0)
> > > - client->irq = bmc150_accel_acpi_gpio_probe(client, data);
> > > + client->irq = bmc150_accel_gpio_probe(client, data);
> > >
> > > if (client->irq >= 0) {
> > > ret = devm_request_threaded_irq(
> > > @@ -1284,14 +1391,24 @@ static const struct dev_pm_ops bmc150_accel_pm_ops = {
> > > };
> > >
> > > static const struct acpi_device_id bmc150_accel_acpi_match[] = {
> > > - {"BSBA0150", 0},
> > > - {"BMC150A", 0},
> > > + {"BSBA0150", bmc150},
> > > + {"BMC150A", bmc150},
> > > + {"BMI055A", bmi055},
> > > + {"BMA0255", bma255},
> > > + {"BMA250E", bma250e},
> > > + {"BMA222E", bma222e},
> > > + {"BMA0280", bma280},
> > > { },
> > > };
> > > MODULE_DEVICE_TABLE(acpi, bmc150_accel_acpi_match);
> > >
> > > static const struct i2c_device_id bmc150_accel_id[] = {
> > > - {"bmc150_accel", 0},
> > > + {"bmc150_accel", bmc150},
> > > + {"bmi055_accel", bmi055},
> > > + {"bma255", bma255},
> > > + {"bma250e", bma250e},
> > > + {"bma222e", bma222e},
> > > + {"bma280", bma280},
> > > {}
> > > };
> > >
> > >
> >
> > --
> >
> > Peter Meerwald
> > +43-664-2444418 (mobile)
> > --
> > To unsubscribe from this list: send the line "unsubscribe linux-iio" in
> > the body of a message to majordomo@vger.kernel.org
> > More majordomo info at http://vger.kernel.org/majordomo-info.html
> --
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next prev parent reply other threads:[~2014-09-01 13:03 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-08-29 8:38 [PATCH v2 0/3] iio: accel: BMC150: add support for more Bosch chips Laurentiu Palcu
2014-08-29 8:38 ` [PATCH v2 1/3] iio: accel: BMC150: fix scale value for 16G Laurentiu Palcu
2014-08-30 10:36 ` Jonathan Cameron
2014-08-29 8:38 ` [PATCH v2 2/3] iio: accel: BMC150: fix issues when CONFIG_PM_RUNTIME is not set Laurentiu Palcu
2014-08-30 10:45 ` Jonathan Cameron
2014-09-01 9:24 ` Laurentiu Palcu
2014-08-29 8:38 ` [PATCH v2 3/3] iio: accel: BMC150: add support for other Bosch chips Laurentiu Palcu
2014-08-30 10:54 ` Jonathan Cameron
2014-09-01 9:11 ` [PATCH v3 " Laurentiu Palcu
2014-09-01 11:02 ` Peter Meerwald
2014-09-01 12:55 ` Laurentiu Palcu
2014-09-01 13:03 ` Laurentiu Palcu [this message]
2014-09-01 14:29 ` [PATCH v4 " Laurentiu Palcu
2014-09-02 9:30 ` [PATCH v5 " Laurentiu Palcu
2014-09-10 19:35 ` Jonathan Cameron
2014-09-10 19:43 ` Srinivas Pandruvada
2014-09-13 20:37 ` Jonathan Cameron
2014-09-01 15:36 ` [PATCH v3 " Joe Perches
2014-09-01 15:51 ` Srinivas Pandruvada
2014-09-02 10:30 ` Laurentiu Palcu
2014-09-10 19:32 ` Jonathan Cameron
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