#include <linux/completion.h>
#include <linux/device.h>
#include <linux/errno.h>
#include <linux/iio/buffer.h>
#include <linux/iio/iio.h>
#include <linux/iio/trigger_consumer.h>
#include <linux/iio/triggered_buffer.h>
#include <linux/jiffies.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/serdev.h>
#include <linux/types.h>
#include <linux/unaligned.h>
#define PMS7003_DRIVER_NAME "pms7003"
#define PMS7003_MAGIC 0x424d
#define PMS7003_MAX_DATA_LENGTH 28
#define PMS7003_CHECKSUM_LENGTH 2
#define PMS7003_PM10_OFFSET 10
#define PMS7003_PM2P5_OFFSET 8
#define PMS7003_PM1_OFFSET 6
#define PMS7003_TIMEOUT msecs_to_jiffies(6000)
#define PMS7003_CMD_LENGTH 7
#define PMS7003_PM_MAX 1000
#define PMS7003_PM_MIN 0
enum {
PM1,
PM2P5,
PM10,
};
enum pms7003_cmd {
CMD_WAKEUP,
CMD_ENTER_PASSIVE_MODE,
CMD_READ_PASSIVE,
CMD_SLEEP,
};
static const u8 pms7003_cmd_tbl[][PMS7003_CMD_LENGTH] = {
[CMD_WAKEUP] = { 0x42, 0x4d, 0xe4, 0x00, 0x01, 0x01, 0x74 },
[CMD_ENTER_PASSIVE_MODE] = { 0x42, 0x4d, 0xe1, 0x00, 0x00, 0x01, 0x70 },
[CMD_READ_PASSIVE] = { 0x42, 0x4d, 0xe2, 0x00, 0x00, 0x01, 0x71 },
[CMD_SLEEP] = { 0x42, 0x4d, 0xe4, 0x00, 0x00, 0x01, 0x73 },
};
struct pms7003_frame {
u8 data[PMS7003_MAX_DATA_LENGTH];
u16 expected_length;
u16 length;
};
struct pms7003_state {
struct serdev_device *serdev;
struct pms7003_frame frame;
struct completion frame_ready;
struct mutex lock;
struct {
u16 data[3];
aligned_s64 ts;
} scan;
};
static int pms7003_do_cmd(struct pms7003_state *state, enum pms7003_cmd cmd)
{
int ret;
ret = serdev_device_write(state->serdev, pms7003_cmd_tbl[cmd],
PMS7003_CMD_LENGTH, PMS7003_TIMEOUT);
if (ret < PMS7003_CMD_LENGTH)
return ret < 0 ? ret : -EIO;
ret = wait_for_completion_interruptible_timeout(&state->frame_ready,
PMS7003_TIMEOUT);
if (!ret)
ret = -ETIMEDOUT;
return ret < 0 ? ret : 0;
}
static u16 pms7003_get_pm(const u8 *data)
{
return clamp_val(get_unaligned_be16(data),
PMS7003_PM_MIN, PMS7003_PM_MAX);
}
static irqreturn_t pms7003_trigger_handler(int irq, void *p)
{
struct iio_poll_func *pf = p;
struct iio_dev *indio_dev = pf->indio_dev;
struct pms7003_state *state = iio_priv(indio_dev);
struct pms7003_frame *frame = &state->frame;
int ret;
mutex_lock(&state->lock);
ret = pms7003_do_cmd(state, CMD_READ_PASSIVE);
if (ret) {
mutex_unlock(&state->lock);
goto err;
}
state->scan.data[PM1] =
pms7003_get_pm(frame->data + PMS7003_PM1_OFFSET);
state->scan.data[PM2P5] =
pms7003_get_pm(frame->data + PMS7003_PM2P5_OFFSET);
state->scan.data[PM10] =
pms7003_get_pm(frame->data + PMS7003_PM10_OFFSET);
mutex_unlock(&state->lock);
iio_push_to_buffers_with_ts(indio_dev, &state->scan, sizeof(state->scan),
iio_get_time_ns(indio_dev));
err:
iio_trigger_notify_done(indio_dev->trig);
return IRQ_HANDLED;
}
static int pms7003_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long mask)
{
struct pms7003_state *state = iio_priv(indio_dev);
struct pms7003_frame *frame = &state->frame;
int ret;
switch (mask) {
case IIO_CHAN_INFO_PROCESSED:
switch (chan->type) {
case IIO_MASSCONCENTRATION:
mutex_lock(&state->lock);
ret = pms7003_do_cmd(state, CMD_READ_PASSIVE);
if (ret) {
mutex_unlock(&state->lock);
return ret;
}
*val = pms7003_get_pm(frame->data + chan->address);
mutex_unlock(&state->lock);
return IIO_VAL_INT;
default:
return -EINVAL;
}
}
return -EINVAL;
}
static const struct iio_info pms7003_info = {
.read_raw = pms7003_read_raw,
};
#define PMS7003_CHAN(_index, _mod, _addr) { \
.type = IIO_MASSCONCENTRATION, \
.modified = 1, \
.channel2 = IIO_MOD_ ## _mod, \
.address = _addr, \
.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), \
.scan_index = _index, \
.scan_type = { \
.sign = 'u', \
.realbits = 10, \
.storagebits = 16, \
.endianness = IIO_CPU, \
}, \
}
static const struct iio_chan_spec pms7003_channels[] = {
PMS7003_CHAN(0, PM1, PMS7003_PM1_OFFSET),
PMS7003_CHAN(1, PM2P5, PMS7003_PM2P5_OFFSET),
PMS7003_CHAN(2, PM10, PMS7003_PM10_OFFSET),
IIO_CHAN_SOFT_TIMESTAMP(3),
};
static u16 pms7003_calc_checksum(struct pms7003_frame *frame)
{
u16 checksum = (PMS7003_MAGIC >> 8) + (u8)(PMS7003_MAGIC & 0xff) +
(frame->length >> 8) + (u8)frame->length;
int i;
for (i = 0; i < frame->length - PMS7003_CHECKSUM_LENGTH; i++)
checksum += frame->data[i];
return checksum;
}
static bool pms7003_frame_is_okay(struct pms7003_frame *frame)
{
int offset = frame->length - PMS7003_CHECKSUM_LENGTH;
u16 checksum = get_unaligned_be16(frame->data + offset);
return checksum == pms7003_calc_checksum(frame);
}
static size_t pms7003_receive_buf(struct serdev_device *serdev, const u8 *buf,
size_t size)
{
struct iio_dev *indio_dev = serdev_device_get_drvdata(serdev);
struct pms7003_state *state = iio_priv(indio_dev);
struct pms7003_frame *frame = &state->frame;
size_t num;
if (!frame->expected_length) {
u16 magic;
if (size < 4)
return 0;
magic = get_unaligned_be16(buf);
if (magic != PMS7003_MAGIC)
return 2;
num = get_unaligned_be16(buf + 2);
if (num <= PMS7003_MAX_DATA_LENGTH) {
frame->expected_length = num;
frame->length = 0;
}
return 4;
}
num = min(size, (size_t)(frame->expected_length - frame->length));
memcpy(frame->data + frame->length, buf, num);
frame->length += num;
if (frame->length == frame->expected_length) {
if (pms7003_frame_is_okay(frame))
complete(&state->frame_ready);
frame->expected_length = 0;
}
return num;
}
static const struct serdev_device_ops pms7003_serdev_ops = {
.receive_buf = pms7003_receive_buf,
.write_wakeup = serdev_device_write_wakeup,
};
static void pms7003_stop(void *data)
{
struct pms7003_state *state = data;
pms7003_do_cmd(state, CMD_SLEEP);
}
static const unsigned long pms7003_scan_masks[] = { 0x07, 0x00 };
static int pms7003_probe(struct serdev_device *serdev)
{
struct pms7003_state *state;
struct iio_dev *indio_dev;
int ret;
indio_dev = devm_iio_device_alloc(&serdev->dev, sizeof(*state));
if (!indio_dev)
return -ENOMEM;
state = iio_priv(indio_dev);
serdev_device_set_drvdata(serdev, indio_dev);
state->serdev = serdev;
indio_dev->info = &pms7003_info;
indio_dev->name = PMS7003_DRIVER_NAME;
indio_dev->channels = pms7003_channels;
indio_dev->num_channels = ARRAY_SIZE(pms7003_channels);
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->available_scan_masks = pms7003_scan_masks;
mutex_init(&state->lock);
init_completion(&state->frame_ready);
serdev_device_set_client_ops(serdev, &pms7003_serdev_ops);
ret = devm_serdev_device_open(&serdev->dev, serdev);
if (ret)
return ret;
serdev_device_set_baudrate(serdev, 9600);
serdev_device_set_flow_control(serdev, false);
ret = serdev_device_set_parity(serdev, SERDEV_PARITY_NONE);
if (ret)
return ret;
ret = pms7003_do_cmd(state, CMD_WAKEUP);
if (ret) {
dev_err(&serdev->dev, "failed to wakeup sensor\n");
return ret;
}
ret = pms7003_do_cmd(state, CMD_ENTER_PASSIVE_MODE);
if (ret) {
dev_err(&serdev->dev, "failed to enter passive mode\n");
return ret;
}
ret = devm_add_action_or_reset(&serdev->dev, pms7003_stop, state);
if (ret)
return ret;
ret = devm_iio_triggered_buffer_setup(&serdev->dev, indio_dev, NULL,
pms7003_trigger_handler, NULL);
if (ret)
return ret;
return devm_iio_device_register(&serdev->dev, indio_dev);
}
static const struct of_device_id pms7003_of_match[] = {
{ .compatible = "plantower,pms1003" },
{ .compatible = "plantower,pms3003" },
{ .compatible = "plantower,pms5003" },
{ .compatible = "plantower,pms6003" },
{ .compatible = "plantower,pms7003" },
{ .compatible = "plantower,pmsa003" },
{ }
};
MODULE_DEVICE_TABLE(of, pms7003_of_match);
static struct serdev_device_driver pms7003_driver = {
.driver = {
.name = PMS7003_DRIVER_NAME,
.of_match_table = pms7003_of_match,
},
.probe = pms7003_probe,
};
module_serdev_device_driver(pms7003_driver);
MODULE_AUTHOR("Tomasz Duszynski <tduszyns@gmail.com>");
MODULE_DESCRIPTION("Plantower PMS7003 particulate matter sensor driver");
MODULE_LICENSE("GPL v2");
