Re: [PATCH 2/2 v5] iio: Add SEMTECH SX9310/9311 sensor driver
From: Andy Shevchenko
Date: Tue Mar 24 2020 - 12:19:03 EST
On Mon, Mar 23, 2020 at 8:46 PM Daniel Campello <campello@xxxxxxxxxxxx> wrote:
>
> Add SEMTECH SX9310/9311 driver.
>
> The device has the following entry points:
>
> Usual frequency:
> - sampling_frequency
> - sampling_frequency_available
>
> Instant reading of current values for different sensors:
> - in_proximity0_raw
> - in_proximity1_raw
> - in_proximity2_raw
> - in_proximity3_comb_raw
> and associated events in events/
...
> +#include <linux/acpi.h>
> +#include <linux/of.h>
No users for these (see ID table handling below), but property.h would
be needed.
...
> +#define SX9310_EVENT_IRQ (SX9310_FAR_IRQ | \
> + SX9310_CLOSE_IRQ)
Better formatting is
#define FOO \
(BAR | ZOO)
...
> +struct sx9310_data {
> + struct i2c_client *client;
Do you really need client? Perhaps struct device will be enough?
> + struct iio_trigger *trig;
> + struct regmap *regmap;
> + /*
> + * Last reading of the proximity status for each channel.
> + * We only send an event to user space when this changes.
> + */
> + bool prox_stat[SX9310_NUM_CHANNELS];
> + bool trigger_enabled;
> + __be16 buffer[SX9310_NUM_CHANNELS +
> + 4]; /* 64-bit data + 64-bit timestamp */
Please, fix formatting.
> +};
...
> +static int sx9310_update_chan_en(struct sx9310_data *data,
> + unsigned int chan_read,
> + unsigned int chan_event)
> +{
> + int ret;
> +
> + if ((data->chan_read | data->chan_event) != (chan_read | chan_event)) {
> + ret = regmap_update_bits(data->regmap, SX9310_REG_PROX_CTRL0,
> + SX9310_CHAN_ENABLED_MASK,
> + chan_read | chan_event);
unsigned int readevent = chan_read | chan_event;
...
if (... != readevent) {
..., readevent);
}
> + if (ret)
> + return ret;
> + }
> + data->chan_read = chan_read;
> + data->chan_event = chan_event;
> + return 0;
> +}
...
> +static int sx9310_read_prox_data(struct sx9310_data *data,
> + const struct iio_chan_spec *chan, __be16 *val)
> +{
> + int ret;
> +
> + ret = regmap_write(data->regmap, SX9310_REG_SENSOR_SEL, chan->channel);
> + if (ret < 0)
> + return ret;
> +
> + return regmap_bulk_read(data->regmap, chan->address, val, 2);
sizeof()?
> +}
...
> + if (data->client->irq > 0) {
> + ret = wait_for_completion_interruptible(&data->completion);
> + reinit_completion(&data->completion);
Logically reinit better to be called before you start measurement.
> + } else {
> + ret = sx9310_wait_for_sample(data);
> + }
...
> + *val = sign_extend32(be16_to_cpu(rawval),
> + (chan->address == SX9310_REG_DIFF_MSB ? 11 : 15));
Too many parentheses.
...
> + mutex_lock(&data->mutex);
> +
> + ret = regmap_update_bits(data->regmap, SX9310_REG_PROX_CTRL0,
> + SX9310_SCAN_PERIOD_MASK,
> + i << SX9310_SCAN_PERIOD_SHIFT);
> +
> + mutex_unlock(&data->mutex);
Btw, can you use locking provided by regmap?
...
> + /*
> + * Even if no event is enabled, we need to wake the thread to
> + * clear the interrupt state by reading SX9310_REG_IRQ_SRC. It
Move it to the next line.
> + * is not possible to do that here because regmap_read takes a
> + * mutex.
> + */
...
> + for (chan = 0; chan < SX9310_NUM_CHANNELS; chan++) {
> + int dir;
> + u64 ev;
> + bool new_prox = val & BIT(chan);
> +
> + if (!(data->chan_event & BIT(chan)))
> + continue;
for_each_set_bit()
> + if (new_prox == data->prox_stat[chan])
> + /* No change on this channel. */
> + continue;
> + }
...
> +static struct attribute *sx9310_attributes[] = {
> + &iio_dev_attr_sampling_frequency_available.dev_attr.attr,
> + NULL,
Comma is not needed for terminator.
> +};
...
> +static int sx9310_buffer_preenable(struct iio_dev *indio_dev)
> +{
> + struct sx9310_data *data = iio_priv(indio_dev);
> + unsigned int channels = 0;
> + int bit, ret;
> +
> + mutex_lock(&data->mutex);
> + for_each_set_bit(bit, indio_dev->active_scan_mask,
> + indio_dev->masklength)
> + channels |= BIT(indio_dev->channels[bit].channel);
unsigned long channels;
...
__set_bit(...);
> + ret = sx9310_update_chan_en(data, channels, data->chan_event);
> + mutex_unlock(&data->mutex);
> + return ret;
> +}
...
> +#define SX_INIT(_reg, _def) \
> + { \
> + .reg = SX9310_REG_##_reg, \
> + .def = _def, \
> + }
Usually it's a good tone to #undef custom macro when they are not
needed anymore.
...
> + for (i = 100; i >= 0; i--) {
> + msleep(20);
> + ret = regmap_read(data->regmap, SX9310_REG_STAT1, &val);
> + if (ret < 0)
> + goto out;
> + if (!(val & SX9310_COMPSTAT_MASK))
> + break;
> + }
NIH of regmap_real_poll_timeout();
> +
> + if (i < 0) {
> + dev_err(&data->client->dev,
> + "initial compensation timed out: 0x%02x", val);
> + ret = -ETIMEDOUT;
> + }
...
> + ret = regmap_write(data->regmap, initval->reg, initval->def);
> + if (ret < 0)
Do you need all these ' < 0'?
> + return ret;
...
> + const struct acpi_device_id *acpi_id;
> + /* id will be NULL when enumerated via ACPI */
> + if (id) {
> + if (id->driver_data != whoami)
> + dev_err(dev, "WHOAMI does not match i2c_device_id: %s",
> + id->name);
> + } else if (ACPI_HANDLE(dev)) {
> + acpi_id = acpi_match_device(dev->driver->acpi_match_table, dev);
> + if (!acpi_id)
> + return -ENODEV;
> + if (acpi_id->driver_data != whoami)
> + dev_err(dev, "WHOAMI does not match acpi_device_id: %s",
> + acpi_id->id);
> + } else
> + return -ENODEV;
device_get_match_data().
...
> +static int sx9310_probe(struct i2c_client *client,
> + const struct i2c_device_id *id)
Can you switch to ->probe_new()?
...
> + indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
> + if (indio_dev == NULL)
if (!indio_dev)
> + return -ENOMEM;
...
> + dev_err(&client->dev, "error in reading WHOAMI register: %d",
> + ret);
If you introduce temporary variable the code will be better to read
struct device *dev = &client->dev;
> + ret = sx9310_set_indio_dev_name(&client->dev, indio_dev, id,
> + data->whoami);
> + if (ret < 0)
> + return ret;
...
> +static const struct acpi_device_id sx9310_acpi_match[] = {
> + { "STH9310", SX9310_WHOAMI_VALUE },
> + { "STH9311", SX9311_WHOAMI_VALUE },
Hmm... May I ask some official proof that these IDs are real and
issued by vendor?
> + {},
No comma.
> +};
> +MODULE_DEVICE_TABLE(acpi, sx9310_acpi_match);
> +static const struct of_device_id sx9310_of_match[] = {
> + { .compatible = "semtech,sx9310" },
> + { .compatible = "semtech,sx9311" },
> + {},
No comma.
> +};
> +MODULE_DEVICE_TABLE(of, sx9310_of_match);
> +
> +static const struct i2c_device_id sx9310_id[] = {
> + { "sx9310", SX9310_WHOAMI_VALUE },
> + { "sx9311", SX9311_WHOAMI_VALUE },
> + {},
No comma.
> +};
> +MODULE_DEVICE_TABLE(i2c, sx9310_id);
...
> + .acpi_match_table = ACPI_PTR(sx9310_acpi_match),
> + .of_match_table = of_match_ptr(sx9310_of_match),
Drop these macros. You probably didn't test with !ACPI and/or !OF --
should be compiler warning.
> + .pm = &sx9310_pm_ops,
> + },
--
With Best Regards,
Andy Shevchenko