Re: [PATCH v4 5/6] iio: imu: kmx61: Add support for data ready triggers

Hartmut Knaack
2014-12-14T23:04:35Z

Daniel Baluta schrieb am 03.12.2014 um 14:31:
> This creates a data ready trigger per IIO device.
>
I found some issues here, and some recommendations. See inline.

> Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
> ---
> drivers/iio/imu/Kconfig | 2 +
> drivers/iio/imu/kmx61.c | 295 +++++++++++++++++++++++++++++++++++++++++++++++-
> 2 files changed, 296 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/iio/imu/Kconfig b/drivers/iio/imu/Kconfig
> index db4221d..5e610f7 100644
> --- a/drivers/iio/imu/Kconfig
> +++ b/drivers/iio/imu/Kconfig
> @@ -28,6 +28,8 @@ config ADIS16480
> config KMX61
> tristate "Kionix KMX61 6-axis accelerometer and magnetometer"
> depends on I2C
> + select IIO_BUFFER
> + select IIO_TRIGGERED_BUFFER
> help
> Say Y here if you want to build a driver for Kionix KMX61 6-axis
> accelerometer and magnetometer.
> diff --git a/drivers/iio/imu/kmx61.c b/drivers/iio/imu/kmx61.c
> index f69ae5a7..0f6816a 100644
> --- a/drivers/iio/imu/kmx61.c
> +++ b/drivers/iio/imu/kmx61.c
> @@ -20,9 +20,14 @@
> #include <linux/pm_runtime.h>
> #include <linux/iio/iio.h>
> #include <linux/iio/sysfs.h>
> +#include <linux/iio/trigger.h>
> +#include <linux/iio/buffer.h>
> +#include <linux/iio/triggered_buffer.h>
> +#include <linux/iio/trigger_consumer.h>
>
> #define KMX61_DRV_NAME "kmx61"
> #define KMX61_GPIO_NAME "kmx61_int"
> +#define KMX61_IRQ_NAME "kmx61_event"
>
> #define KMX61_REG_WHO_AM_I 0x00
>
> @@ -55,9 +60,11 @@
> #define KMX61_MAG_ZOUT_L 0x16
> #define KMX61_MAG_ZOUT_H 0x17
>
> +#define KMX61_REG_INL 0x28
> #define KMX61_REG_STBY 0x29
> #define KMX61_REG_CTRL1 0x2A
> #define KMX61_REG_ODCNTL 0x2C
> +#define KMX61_REG_INC1 0x2D
>
> #define KMX61_ACC_STBY_BIT BIT(0)
> #define KMX61_MAG_STBY_BIT BIT(1)
> @@ -67,6 +74,13 @@
>
> #define KMX61_REG_CTRL1_GSEL_MASK 0x03
>
> +#define KMX61_REG_CTRL1_BIT_RES BIT(4)
> +#define KMX61_REG_CTRL1_BIT_DRDYE BIT(5)
> +
> +#define KMX61_REG_INC1_BIT_DRDYM BIT(1)
> +#define KMX61_REG_INC1_BIT_DRDYA BIT(2)
> +#define KMX61_REG_INC1_BIT_IEN BIT(5)
> +
> #define KMX61_ACC_ODR_SHIFT 0
> #define KMX61_MAG_ODR_SHIFT 4
> #define KMX61_ACC_ODR_MASK 0x0F
> @@ -100,9 +114,13 @@ struct kmx61_data {
>
> /* accelerometer specific data */
> struct iio_dev *acc_indio_dev;
> + struct iio_trigger *acc_dready_trig;
> + bool acc_dready_trig_on;
>
> /* magnetometer specific data */
> struct iio_dev *mag_indio_dev;
> + struct iio_trigger *mag_dready_trig;
> + bool mag_dready_trig_on;
> };
>
> enum kmx61_range {
> @@ -466,6 +484,69 @@ static int kmx61_chip_init(struct kmx61_data *data)
> return 0;
> }
>
> +static int kmx61_setup_new_data_interrupt(struct kmx61_data *data,
> + bool status, u8 device)
> +{
> + u8 mode;
> + int ret;
> +
> + 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 = i2c_smbus_read_byte_data(data->client, KMX61_REG_INC1);
> + if (ret < 0) {
> + dev_err(&data->client->dev, "Error reading reg_ctrl1\n");
> + return ret;
> + }
> +
> + if (status) {
> + ret |= KMX61_REG_INC1_BIT_IEN;
> + if (device & KMX61_ACC)
> + ret |= KMX61_REG_INC1_BIT_DRDYA;
> + if (device & KMX61_MAG)
> + ret |= KMX61_REG_INC1_BIT_DRDYM;
> + } else {
> + ret &= ~KMX61_REG_INC1_BIT_IEN;
> + if (device & KMX61_ACC)
> + ret &= ~KMX61_REG_INC1_BIT_DRDYA;
> + if (device & KMX61_MAG)
> + ret &= ~KMX61_REG_INC1_BIT_DRDYM;
> + }
> + ret = i2c_smbus_write_byte_data(data->client, KMX61_REG_INC1, ret);
> + if (ret < 0) {
> + dev_err(&data->client->dev, "Error writing reg_int_ctrl1\n");
> + return 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;
> + }
> +
> + if (status)
> + ret |= KMX61_REG_CTRL1_BIT_DRDYE;
> + else
> + ret &= ~KMX61_REG_CTRL1_BIT_DRDYE;
> +
> + 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;
> + }
> +
> + ret = kmx61_set_mode(data, mode, KMX61_ACC | KMX61_MAG, true);
> + if (ret)
> + return ret;
> +
> + return 0;
No need to check ret here, could be simply: return kmx61_set_mode(...);
> +}
> +
> /**
> * kmx61_set_power_state() - set power state for kmx61 @device
> * @data - kmx61 device private pointer
> @@ -626,11 +707,34 @@ static int kmx61_write_raw(struct iio_dev *indio_dev,
> }
> }
>
> +static int kmx61_acc_validate_trigger(struct iio_dev *indio_dev,
> + struct iio_trigger *trig)
> +{
> + struct kmx61_data *data = kmx61_get_data(indio_dev);
> +
> + if (data->acc_dready_trig != trig)
> + return -EINVAL;
> +
> + return 0;
> +}
> +
> +static int kmx61_mag_validate_trigger(struct iio_dev *indio_dev,
> + struct iio_trigger *trig)
> +{
> + struct kmx61_data *data = kmx61_get_data(indio_dev);
> +
> + if (data->mag_dready_trig != trig)
> + return -EINVAL;
> +
> + return 0;
> +}
> +
> static const struct iio_info kmx61_acc_info = {
> .driver_module = THIS_MODULE,
> .read_raw = kmx61_read_raw,
> .write_raw = kmx61_write_raw,
> .attrs = &kmx61_acc_attribute_group,
> + .validate_trigger = kmx61_acc_validate_trigger,
> };
>
> static const struct iio_info kmx61_mag_info = {
> @@ -638,8 +742,109 @@ static const struct iio_info kmx61_mag_info = {
> .read_raw = kmx61_read_raw,
> .write_raw = kmx61_write_raw,
> .attrs = &kmx61_mag_attribute_group,
> + .validate_trigger = kmx61_mag_validate_trigger,
> +};
> +
> +
> +static int kmx61_data_rdy_trigger_set_state(struct iio_trigger *trig,
> + bool state)
> +{
> + int ret = 0;
No need to initialize ret.
> + u8 device;
> +
> + struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
> + struct kmx61_data *data = iio_priv(indio_dev);
Shouldn't that be using kmx61_get_data()?
> +
> + mutex_lock(&data->lock);
> +
> + if (data->acc_dready_trig == trig)
> + device = KMX61_ACC;
> + else
> + device = KMX61_MAG;
> +
> + ret = kmx61_set_power_state(data, state, device);
> + if (ret < 0) {
> + mutex_unlock(&data->lock);
> + return ret;
> + }
> +
> + ret = kmx61_setup_new_data_interrupt(data, state, device);
> + if (ret < 0) {
> + kmx61_set_power_state(data, false, device);
> + mutex_unlock(&data->lock);
> + return ret;
> + }
> +
> + if (data->acc_dready_trig == trig)
> + data->acc_dready_trig_on = state;
> + else
> + data->mag_dready_trig_on = state;
> +
> + mutex_unlock(&data->lock);
> +
> + return 0;
Could reduce code repetition by placing an error-out label above the
mutex_unlock and then just do: return (ret < 0) ? ret : 0;
(Or even: return ret;)
> +}
> +
> +static int kmx61_trig_try_reenable(struct iio_trigger *trig)
> +{
> + struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
> + struct kmx61_data *data = kmx61_get_data(indio_dev);
> + int ret;
> +
> + ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_INL);
> + if (ret < 0) {
> + dev_err(&data->client->dev, "Error reading reg_inl\n");
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static const struct iio_trigger_ops kmx61_trigger_ops = {
> + .set_trigger_state = kmx61_data_rdy_trigger_set_state,
> + .try_reenable = kmx61_trig_try_reenable,
> + .owner = THIS_MODULE,
> };
>
> +static irqreturn_t kmx61_data_rdy_trig_poll(int irq, void *private)
> +{
> + struct kmx61_data *data = private;
> +
> + if (data->acc_dready_trig_on)
> + iio_trigger_poll(data->acc_dready_trig);
> + if (data->mag_dready_trig_on)
> + iio_trigger_poll(data->mag_dready_trig);
> +
> + return IRQ_HANDLED;
> +}
> +
> +static irqreturn_t kmx61_trigger_handler(int irq, void *p)
> +{
> + struct iio_poll_func *pf = p;
> + struct iio_dev *indio_dev = pf->indio_dev;
> + struct kmx61_data *data = kmx61_get_data(indio_dev);
> + int bit, ret, i = 0;
> + s16 buffer[8];
> +
> + mutex_lock(&data->lock);
> + for_each_set_bit(bit, indio_dev->buffer->scan_mask,
> + indio_dev->masklength) {
> + ret = kmx61_read_measurement(data, KMX61_ACC_XOUT_L, bit);
> + if (ret < 0) {
> + mutex_unlock(&data->lock);
> + goto err;
> + }
> + buffer[i++] = ret;
> + }
> + mutex_unlock(&data->lock);
> +
> + iio_push_to_buffers(indio_dev, buffer);
> +err:
> + iio_trigger_notify_done(indio_dev->trig);
> +
> + return IRQ_HANDLED;
> +}
> +
> static const char *kmx61_match_acpi_device(struct device *dev)
> {
> const struct acpi_device_id *id;
> @@ -702,6 +907,32 @@ static struct iio_dev *kmx61_indiodev_setup(struct kmx61_data *data,
> return indio_dev;
> }
>
> +static struct iio_trigger *kmx61_trigger_setup(struct kmx61_data *data,
> + struct iio_dev *indio_dev,
> + const char *tag)
> +{
> + struct iio_trigger *trig;
> + int ret;
> +
> + trig = devm_iio_trigger_alloc(&data->client->dev,
> + "%s-%s-dev%d",
> + indio_dev->name,
> + tag,
> + indio_dev->id);
> + if (!trig)
> + return ERR_PTR(-ENOMEM);
> +
> + trig->dev.parent = &data->client->dev;
> + trig->ops = &kmx61_trigger_ops;
> + iio_trigger_set_drvdata(trig, indio_dev);
> +
> + ret = iio_trigger_register(trig);
> + if (ret)
> + return ERR_PTR(ret);
> +
> + return trig;
> +}
> +
> static int kmx61_probe(struct i2c_client *client,
> const struct i2c_device_id *id)
> {
> @@ -748,10 +979,55 @@ static int kmx61_probe(struct i2c_client *client,
> if (client->irq < 0)
> client->irq = kmx61_gpio_probe(client, data);
>
> + if (client->irq >= 0) {
> + ret = devm_request_threaded_irq(&client->dev, client->irq,
> + kmx61_data_rdy_trig_poll,
> + NULL,
> + IRQF_TRIGGER_RISING,
> + KMX61_IRQ_NAME,
> + data);
> + if (ret)
> + goto err_chip_uninit;
> +
> + data->acc_dready_trig =
> + kmx61_trigger_setup(data, data->acc_indio_dev,
> + "dready");
> + if (IS_ERR(data->acc_dready_trig))
> + return PTR_ERR(data->acc_dready_trig);
Better store error value in ret and goto err_chip_uninit.
> +
> + data->mag_dready_trig =
> + kmx61_trigger_setup(data, data->mag_indio_dev,
> + "dready");
> + if (IS_ERR(data->mag_dready_trig)) {
> + ret = PTR_ERR(data->mag_dready_trig);
> + goto err_trigger_unregister;
> + }
> +
> + ret = iio_triggered_buffer_setup(data->acc_indio_dev,
> + &iio_pollfunc_store_time,
> + kmx61_trigger_handler,
> + NULL);
> + if (ret < 0) {
> + dev_err(&data->client->dev,
> + "Failed to setup acc triggered buffer\n");
> + goto err_trigger_unregister;
> + }
> +
> + ret = iio_triggered_buffer_setup(data->mag_indio_dev,
> + &iio_pollfunc_store_time,
> + kmx61_trigger_handler,
> + NULL);
> + if (ret < 0) {
> + dev_err(&data->client->dev,
> + "Failed to setup mag triggered buffer\n");
> + goto err_trigger_unregister;
Better make sure to call iio_triggered_buffer_cleanup for data->acc_indio_dev?
> + }
> + }
> +
> ret = iio_device_register(data->acc_indio_dev);
> if (ret < 0) {
> dev_err(&client->dev, "Failed to register acc iio device\n");
> - goto err_chip_uninit;
> + goto err_buffer_cleanup;
> }
>
> ret = iio_device_register(data->mag_indio_dev);
> @@ -774,6 +1050,16 @@ err_iio_unregister_mag:
> iio_device_unregister(data->mag_indio_dev);
> err_iio_unregister_acc:
> iio_device_unregister(data->acc_indio_dev);
> +err_buffer_cleanup:
> + if (client->irq >= 0) {
> + iio_triggered_buffer_cleanup(data->acc_indio_dev);
> + iio_triggered_buffer_cleanup(data->mag_indio_dev);
> + }
> +err_trigger_unregister:
> + if (data->acc_dready_trig)
> + iio_trigger_unregister(data->acc_dready_trig);
> + if (data->mag_dready_trig)
> + iio_trigger_unregister(data->mag_dready_trig);
> err_chip_uninit:
> kmx61_set_mode(data, KMX61_ALL_STBY, KMX61_ACC | KMX61_MAG, true);
> return ret;
> @@ -790,6 +1076,13 @@ static int kmx61_remove(struct i2c_client *client)
> iio_device_unregister(data->acc_indio_dev);
> iio_device_unregister(data->mag_indio_dev);
>
> + if (client->irq >= 0) {
> + iio_triggered_buffer_cleanup(data->acc_indio_dev);
> + iio_triggered_buffer_cleanup(data->mag_indio_dev);
> + iio_trigger_unregister(data->acc_dready_trig);
> + iio_trigger_unregister(data->mag_dready_trig);
Minor nitpick: could be in reverse order of initialization (mag before acc).
Although we missed it for iio_device_unregister() :-(
> + }
> +
> mutex_lock(&data->lock);
> kmx61_set_mode(data, KMX61_ALL_STBY, KMX61_ACC | KMX61_MAG, true);
> mutex_unlock(&data->lock);
>