Merge tag 'staging-5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging

Pull staging/IIO updates from Greg KH:
 "Here is the big staging/iio driver pull request for 5.1-rc1.

  Lots of good IIO driver updates and cleanups in here as always.
  Combined with the removal of the xgifb driver, we have a net "loss" of
  over 9000 lines in the pull request, always a nice thing.

  As the outreachy application process is currently happening, there are
  loads of tiny checkpatch cleanup fixes all over the staging tree,
  which accounts for the majority of the fixups"

* tag 'staging-5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (341 commits)
  staging: mt7621-dma: remove license boilerplate text
  staging: mt7621-dma: add SPDX GPL-2.0+ license identifier
  Staging: ks7010: Replace typecast to int
  Staging: vt6655: Align a static function declaration
  staging: speakup: fix line over 80 characters.
  staging: mt7621-eth: Remove license boilerplate text
  staging: mt7621-eth: Add SPDX license identifier
  staging: ks7010: removed custom Michael MIC implementation.
  staging: rtl8192e: Fix space and suspect issue
  Staging: vt6655: Modify comment style of SPDX License Identifier
  Staging: vt6655: Modify comment style for SPDX-License-Identifier
  Staging: vt6655: Align a function declaration
  Staging: vt6655: Alignment of function declaration
  staging: rtl8712: Fix indentation issue
  staging: wilc1000: fix incorrent type in initializer
  staging: rtl8188eu: remove unused P2P_PRIVATE_IOCTL_SET_LEN
  staging: rtl8188eu: remove unused enum P2P_PROTO_WK_ID
  staging: rtl8723bs: Remove duplicated include from drv_types.h
  Staging: vt6655: Alignment should match open parenthesis
  staging: erofs: fix mis-acted TAIL merging behavior
  ...

1 files changed, 548 insertions, 0 deletions

diff --git a/drivers/iio/chemical/sps30.c b/drivers/iio/chemical/sps30.c
new file mode 100644
index 000000000000..edbb956e81e8
--- /dev/null
+++ b/drivers/iio/chemical/sps30.c
@@ -0,0 +1,548 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Sensirion SPS30 particulate matter sensor driver
+ *
+ * Copyright (c) Tomasz Duszynski <tduszyns@gmail.com>
+ *
+ * I2C slave address: 0x69
+ */
+
+#include <asm/unaligned.h>
+#include <linux/crc8.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+
+#define SPS30_CRC8_POLYNOMIAL 0x31
+/* max number of bytes needed to store PM measurements or serial string */
+#define SPS30_MAX_READ_SIZE 48
+/* sensor measures reliably up to 3000 ug / m3 */
+#define SPS30_MAX_PM 3000
+/* minimum and maximum self cleaning periods in seconds */
+#define SPS30_AUTO_CLEANING_PERIOD_MIN 0
+#define SPS30_AUTO_CLEANING_PERIOD_MAX 604800
+
+/* SPS30 commands */
+#define SPS30_START_MEAS 0x0010
+#define SPS30_STOP_MEAS 0x0104
+#define SPS30_RESET 0xd304
+#define SPS30_READ_DATA_READY_FLAG 0x0202
+#define SPS30_READ_DATA 0x0300
+#define SPS30_READ_SERIAL 0xd033
+#define SPS30_START_FAN_CLEANING 0x5607
+#define SPS30_AUTO_CLEANING_PERIOD 0x8004
+/* not a sensor command per se, used only to distinguish write from read */
+#define SPS30_READ_AUTO_CLEANING_PERIOD 0x8005
+
+enum {
+	PM1,
+	PM2P5,
+	PM4,
+	PM10,
+};
+
+enum {
+	RESET,
+	MEASURING,
+};
+
+struct sps30_state {
+	struct i2c_client *client;
+	/*
+	 * Guards against concurrent access to sensor registers.
+	 * Must be held whenever sequence of commands is to be executed.
+	 */
+	struct mutex lock;
+	int state;
+};
+
+DECLARE_CRC8_TABLE(sps30_crc8_table);
+
+static int sps30_write_then_read(struct sps30_state *state, u8 *txbuf,
+				 int txsize, u8 *rxbuf, int rxsize)
+{
+	int ret;
+
+	/*
+	 * Sensor does not support repeated start so instead of
+	 * sending two i2c messages in a row we just send one by one.
+	 */
+	ret = i2c_master_send(state->client, txbuf, txsize);
+	if (ret != txsize)
+		return ret < 0 ? ret : -EIO;
+
+	if (!rxbuf)
+		return 0;
+
+	ret = i2c_master_recv(state->client, rxbuf, rxsize);
+	if (ret != rxsize)
+		return ret < 0 ? ret : -EIO;
+
+	return 0;
+}
+
+static int sps30_do_cmd(struct sps30_state *state, u16 cmd, u8 *data, int size)
+{
+	/*
+	 * Internally sensor stores measurements in a following manner:
+	 *
+	 * PM1: upper two bytes, crc8, lower two bytes, crc8
+	 * PM2P5: upper two bytes, crc8, lower two bytes, crc8
+	 * PM4: upper two bytes, crc8, lower two bytes, crc8
+	 * PM10: upper two bytes, crc8, lower two bytes, crc8
+	 *
+	 * What follows next are number concentration measurements and
+	 * typical particle size measurement which we omit.
+	 */
+	u8 buf[SPS30_MAX_READ_SIZE] = { cmd >> 8, cmd };
+	int i, ret = 0;
+
+	switch (cmd) {
+	case SPS30_START_MEAS:
+		buf[2] = 0x03;
+		buf[3] = 0x00;
+		buf[4] = crc8(sps30_crc8_table, &buf[2], 2, CRC8_INIT_VALUE);
+		ret = sps30_write_then_read(state, buf, 5, NULL, 0);
+		break;
+	case SPS30_STOP_MEAS:
+	case SPS30_RESET:
+	case SPS30_START_FAN_CLEANING:
+		ret = sps30_write_then_read(state, buf, 2, NULL, 0);
+		break;
+	case SPS30_READ_AUTO_CLEANING_PERIOD:
+		buf[0] = SPS30_AUTO_CLEANING_PERIOD >> 8;
+		buf[1] = (u8)SPS30_AUTO_CLEANING_PERIOD;
+		/* fall through */
+	case SPS30_READ_DATA_READY_FLAG:
+	case SPS30_READ_DATA:
+	case SPS30_READ_SERIAL:
+		/* every two data bytes are checksummed */
+		size += size / 2;
+		ret = sps30_write_then_read(state, buf, 2, buf, size);
+		break;
+	case SPS30_AUTO_CLEANING_PERIOD:
+		buf[2] = data[0];
+		buf[3] = data[1];
+		buf[4] = crc8(sps30_crc8_table, &buf[2], 2, CRC8_INIT_VALUE);
+		buf[5] = data[2];
+		buf[6] = data[3];
+		buf[7] = crc8(sps30_crc8_table, &buf[5], 2, CRC8_INIT_VALUE);
+		ret = sps30_write_then_read(state, buf, 8, NULL, 0);
+		break;
+	}
+
+	if (ret)
+		return ret;
+
+	/* validate received data and strip off crc bytes */
+	for (i = 0; i < size; i += 3) {
+		u8 crc = crc8(sps30_crc8_table, &buf[i], 2, CRC8_INIT_VALUE);
+
+		if (crc != buf[i + 2]) {
+			dev_err(&state->client->dev,
+				"data integrity check failed\n");
+			return -EIO;
+		}
+
+		*data++ = buf[i];
+		*data++ = buf[i + 1];
+	}
+
+	return 0;
+}
+
+static s32 sps30_float_to_int_clamped(const u8 *fp)
+{
+	int val = get_unaligned_be32(fp);
+	int mantissa = val & GENMASK(22, 0);
+	/* this is fine since passed float is always non-negative */
+	int exp = val >> 23;
+	int fraction, shift;
+
+	/* special case 0 */
+	if (!exp && !mantissa)
+		return 0;
+
+	exp -= 127;
+	if (exp < 0) {
+		/* return values ranging from 1 to 99 */
+		return ((((1 << 23) + mantissa) * 100) >> 23) >> (-exp);
+	}
+
+	/* return values ranging from 100 to 300000 */
+	shift = 23 - exp;
+	val = (1 << exp) + (mantissa >> shift);
+	if (val >= SPS30_MAX_PM)
+		return SPS30_MAX_PM * 100;
+
+	fraction = mantissa & GENMASK(shift - 1, 0);
+
+	return val * 100 + ((fraction * 100) >> shift);
+}
+
+static int sps30_do_meas(struct sps30_state *state, s32 *data, int size)
+{
+	int i, ret, tries = 5;
+	u8 tmp[16];
+
+	if (state->state == RESET) {
+		ret = sps30_do_cmd(state, SPS30_START_MEAS, NULL, 0);
+		if (ret)
+			return ret;
+
+		state->state = MEASURING;
+	}
+
+	while (tries--) {
+		ret = sps30_do_cmd(state, SPS30_READ_DATA_READY_FLAG, tmp, 2);
+		if (ret)
+			return -EIO;
+
+		/* new measurements ready to be read */
+		if (tmp[1] == 1)
+			break;
+
+		msleep_interruptible(300);
+	}
+
+	if (tries == -1)
+		return -ETIMEDOUT;
+
+	ret = sps30_do_cmd(state, SPS30_READ_DATA, tmp, sizeof(int) * size);
+	if (ret)
+		return ret;
+
+	for (i = 0; i < size; i++)
+		data[i] = sps30_float_to_int_clamped(&tmp[4 * i]);
+
+	return 0;
+}
+
+static irqreturn_t sps30_trigger_handler(int irq, void *p)
+{
+	struct iio_poll_func *pf = p;
+	struct iio_dev *indio_dev = pf->indio_dev;
+	struct sps30_state *state = iio_priv(indio_dev);
+	int ret;
+	s32 data[4 + 2]; /* PM1, PM2P5, PM4, PM10, timestamp */
+
+	mutex_lock(&state->lock);
+	ret = sps30_do_meas(state, data, 4);
+	mutex_unlock(&state->lock);
+	if (ret)
+		goto err;
+
+	iio_push_to_buffers_with_timestamp(indio_dev, data,
+					   iio_get_time_ns(indio_dev));
+err:
+	iio_trigger_notify_done(indio_dev->trig);
+
+	return IRQ_HANDLED;
+}
+
+static int sps30_read_raw(struct iio_dev *indio_dev,
+			  struct iio_chan_spec const *chan,
+			  int *val, int *val2, long mask)
+{
+	struct sps30_state *state = iio_priv(indio_dev);
+	int data[4], ret = -EINVAL;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_PROCESSED:
+		switch (chan->type) {
+		case IIO_MASSCONCENTRATION:
+			mutex_lock(&state->lock);
+			/* read up to the number of bytes actually needed */
+			switch (chan->channel2) {
+			case IIO_MOD_PM1:
+				ret = sps30_do_meas(state, data, 1);
+				break;
+			case IIO_MOD_PM2P5:
+				ret = sps30_do_meas(state, data, 2);
+				break;
+			case IIO_MOD_PM4:
+				ret = sps30_do_meas(state, data, 3);
+				break;
+			case IIO_MOD_PM10:
+				ret = sps30_do_meas(state, data, 4);
+				break;
+			}
+			mutex_unlock(&state->lock);
+			if (ret)
+				return ret;
+
+			*val = data[chan->address] / 100;
+			*val2 = (data[chan->address] % 100) * 10000;
+
+			return IIO_VAL_INT_PLUS_MICRO;
+		default:
+			return -EINVAL;
+		}
+	case IIO_CHAN_INFO_SCALE:
+		switch (chan->type) {
+		case IIO_MASSCONCENTRATION:
+			switch (chan->channel2) {
+			case IIO_MOD_PM1:
+			case IIO_MOD_PM2P5:
+			case IIO_MOD_PM4:
+			case IIO_MOD_PM10:
+				*val = 0;
+				*val2 = 10000;
+
+				return IIO_VAL_INT_PLUS_MICRO;
+			default:
+				return -EINVAL;
+			}
+		default:
+			return -EINVAL;
+		}
+	}
+
+	return -EINVAL;
+}
+
+static int sps30_do_cmd_reset(struct sps30_state *state)
+{
+	int ret;
+
+	ret = sps30_do_cmd(state, SPS30_RESET, NULL, 0);
+	msleep(300);
+	/*
+	 * Power-on-reset causes sensor to produce some glitch on i2c bus and
+	 * some controllers end up in error state. Recover simply by placing
+	 * some data on the bus, for example STOP_MEAS command, which
+	 * is NOP in this case.
+	 */
+	sps30_do_cmd(state, SPS30_STOP_MEAS, NULL, 0);
+	state->state = RESET;
+
+	return ret;
+}
+
+static ssize_t start_cleaning_store(struct device *dev,
+				    struct device_attribute *attr,
+				    const char *buf, size_t len)
+{
+	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+	struct sps30_state *state = iio_priv(indio_dev);
+	int val, ret;
+
+	if (kstrtoint(buf, 0, &val) || val != 1)
+		return -EINVAL;
+
+	mutex_lock(&state->lock);
+	ret = sps30_do_cmd(state, SPS30_START_FAN_CLEANING, NULL, 0);
+	mutex_unlock(&state->lock);
+	if (ret)
+		return ret;
+
+	return len;
+}
+
+static ssize_t cleaning_period_show(struct device *dev,
+				      struct device_attribute *attr,
+				      char *buf)
+{
+	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+	struct sps30_state *state = iio_priv(indio_dev);
+	u8 tmp[4];
+	int ret;
+
+	mutex_lock(&state->lock);
+	ret = sps30_do_cmd(state, SPS30_READ_AUTO_CLEANING_PERIOD, tmp, 4);
+	mutex_unlock(&state->lock);
+	if (ret)
+		return ret;
+
+	return sprintf(buf, "%d\n", get_unaligned_be32(tmp));
+}
+
+static ssize_t cleaning_period_store(struct device *dev,
+				       struct device_attribute *attr,
+				       const char *buf, size_t len)
+{
+	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+	struct sps30_state *state = iio_priv(indio_dev);
+	int val, ret;
+	u8 tmp[4];
+
+	if (kstrtoint(buf, 0, &val))
+		return -EINVAL;
+
+	if ((val < SPS30_AUTO_CLEANING_PERIOD_MIN) ||
+	    (val > SPS30_AUTO_CLEANING_PERIOD_MAX))
+		return -EINVAL;
+
+	put_unaligned_be32(val, tmp);
+
+	mutex_lock(&state->lock);
+	ret = sps30_do_cmd(state, SPS30_AUTO_CLEANING_PERIOD, tmp, 0);
+	if (ret) {
+		mutex_unlock(&state->lock);
+		return ret;
+	}
+
+	msleep(20);
+
+	/*
+	 * sensor requires reset in order to return up to date self cleaning
+	 * period
+	 */
+	ret = sps30_do_cmd_reset(state);
+	if (ret)
+		dev_warn(dev,
+			 "period changed but reads will return the old value\n");
+
+	mutex_unlock(&state->lock);
+
+	return len;
+}
+
+static ssize_t cleaning_period_available_show(struct device *dev,
+					      struct device_attribute *attr,
+					      char *buf)
+{
+	return snprintf(buf, PAGE_SIZE, "[%d %d %d]\n",
+			SPS30_AUTO_CLEANING_PERIOD_MIN, 1,
+			SPS30_AUTO_CLEANING_PERIOD_MAX);
+}
+
+static IIO_DEVICE_ATTR_WO(start_cleaning, 0);
+static IIO_DEVICE_ATTR_RW(cleaning_period, 0);
+static IIO_DEVICE_ATTR_RO(cleaning_period_available, 0);
+
+static struct attribute *sps30_attrs[] = {
+	&iio_dev_attr_start_cleaning.dev_attr.attr,
+	&iio_dev_attr_cleaning_period.dev_attr.attr,
+	&iio_dev_attr_cleaning_period_available.dev_attr.attr,
+	NULL
+};
+
+static const struct attribute_group sps30_attr_group = {
+	.attrs = sps30_attrs,
+};
+
+static const struct iio_info sps30_info = {
+	.attrs = &sps30_attr_group,
+	.read_raw = sps30_read_raw,
+};
+
+#define SPS30_CHAN(_index, _mod) { \
+	.type = IIO_MASSCONCENTRATION, \
+	.modified = 1, \
+	.channel2 = IIO_MOD_ ## _mod, \
+	.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), \
+	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
+	.address = _mod, \
+	.scan_index = _index, \
+	.scan_type = { \
+		.sign = 'u', \
+		.realbits = 19, \
+		.storagebits = 32, \
+		.endianness = IIO_CPU, \
+	}, \
+}
+
+static const struct iio_chan_spec sps30_channels[] = {
+	SPS30_CHAN(0, PM1),
+	SPS30_CHAN(1, PM2P5),
+	SPS30_CHAN(2, PM4),
+	SPS30_CHAN(3, PM10),
+	IIO_CHAN_SOFT_TIMESTAMP(4),
+};
+
+static void sps30_stop_meas(void *data)
+{
+	struct sps30_state *state = data;
+
+	sps30_do_cmd(state, SPS30_STOP_MEAS, NULL, 0);
+}
+
+static const unsigned long sps30_scan_masks[] = { 0x0f, 0x00 };
+
+static int sps30_probe(struct i2c_client *client)
+{
+	struct iio_dev *indio_dev;
+	struct sps30_state *state;
+	u8 buf[32];
+	int ret;
+
+	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
+		return -EOPNOTSUPP;
+
+	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*state));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	state = iio_priv(indio_dev);
+	i2c_set_clientdata(client, indio_dev);
+	state->client = client;
+	state->state = RESET;
+	indio_dev->dev.parent = &client->dev;
+	indio_dev->info = &sps30_info;
+	indio_dev->name = client->name;
+	indio_dev->channels = sps30_channels;
+	indio_dev->num_channels = ARRAY_SIZE(sps30_channels);
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->available_scan_masks = sps30_scan_masks;
+
+	mutex_init(&state->lock);
+	crc8_populate_msb(sps30_crc8_table, SPS30_CRC8_POLYNOMIAL);
+
+	ret = sps30_do_cmd_reset(state);
+	if (ret) {
+		dev_err(&client->dev, "failed to reset device\n");
+		return ret;
+	}
+
+	ret = sps30_do_cmd(state, SPS30_READ_SERIAL, buf, sizeof(buf));
+	if (ret) {
+		dev_err(&client->dev, "failed to read serial number\n");
+		return ret;
+	}
+	/* returned serial number is already NUL terminated */
+	dev_info(&client->dev, "serial number: %s\n", buf);
+
+	ret = devm_add_action_or_reset(&client->dev, sps30_stop_meas, state);
+	if (ret)
+		return ret;
+
+	ret = devm_iio_triggered_buffer_setup(&client->dev, indio_dev, NULL,
+					      sps30_trigger_handler, NULL);
+	if (ret)
+		return ret;
+
+	return devm_iio_device_register(&client->dev, indio_dev);
+}
+
+static const struct i2c_device_id sps30_id[] = {
+	{ "sps30" },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, sps30_id);
+
+static const struct of_device_id sps30_of_match[] = {
+	{ .compatible = "sensirion,sps30" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, sps30_of_match);
+
+static struct i2c_driver sps30_driver = {
+	.driver = {
+		.name = "sps30",
+		.of_match_table = sps30_of_match,
+	},
+	.id_table = sps30_id,
+	.probe_new = sps30_probe,
+};
+module_i2c_driver(sps30_driver);
+
+MODULE_AUTHOR("Tomasz Duszynski <tduszyns@gmail.com>");
+MODULE_DESCRIPTION("Sensirion SPS30 particulate matter sensor driver");
+MODULE_LICENSE("GPL v2");