drivers/iio/pressure/hp03.c

Source file repositories/reference/linux-study-clean/drivers/iio/pressure/hp03.c

File Facts

System
Linux kernel
Corpus path
drivers/iio/pressure/hp03.c
Extension
.c
Size
7068 bytes
Lines
293
Domain
Driver Families
Bucket
drivers/iio
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

struct hp03_priv {
	struct i2c_client	*client;
	struct mutex		lock;
	struct gpio_desc	*xclr_gpio;

	struct i2c_client	*eeprom_client;
	struct regmap		*eeprom_regmap;

	s32			pressure;	/* kPa */
	s32			temp;		/* Deg. C */
};

static const struct iio_chan_spec hp03_channels[] = {
	{
		.type = IIO_PRESSURE,
		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
	},
	{
		.type = IIO_TEMP,
		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
	},
};

static bool hp03_is_writeable_reg(struct device *dev, unsigned int reg)
{
	return false;
}

static bool hp03_is_volatile_reg(struct device *dev, unsigned int reg)
{
	return false;
}

static const struct regmap_config hp03_regmap_config = {
	.reg_bits	= 8,
	.val_bits	= 8,

	.max_register	= HP03_EEPROM_CD_OFFSET + 1,
	.cache_type	= REGCACHE_RBTREE,

	.writeable_reg	= hp03_is_writeable_reg,
	.volatile_reg	= hp03_is_volatile_reg,
};

static int hp03_get_temp_pressure(struct hp03_priv *priv, const u8 reg)
{
	int ret;

	ret = i2c_smbus_write_byte_data(priv->client, HP03_ADC_WRITE_REG, reg);
	if (ret < 0)
		return ret;

	msleep(50);	/* Wait for conversion to finish */

	return i2c_smbus_read_word_data(priv->client, HP03_ADC_READ_REG);
}

static int hp03_update_temp_pressure(struct hp03_priv *priv)
{
	struct device *dev = &priv->client->dev;
	u8 coefs[18];
	u16 cx_val[7];
	int ab_val, d1_val, d2_val, diff_val, dut, off, sens, x;
	int i, ret;

	/* Sample coefficients from EEPROM */
	ret = regmap_bulk_read(priv->eeprom_regmap, HP03_EEPROM_CX_OFFSET,
			       coefs, sizeof(coefs));
	if (ret < 0) {
		dev_err(dev, "Failed to read EEPROM (reg=%02x)\n",
			HP03_EEPROM_CX_OFFSET);
		return ret;
	}

	/* Sample Temperature and Pressure */
	gpiod_set_value_cansleep(priv->xclr_gpio, 1);

	ret = hp03_get_temp_pressure(priv, HP03_ADC_READ_PRESSURE);
	if (ret < 0) {
		dev_err(dev, "Failed to read pressure\n");
		goto err_adc;
	}
	d1_val = ret;

	ret = hp03_get_temp_pressure(priv, HP03_ADC_READ_TEMP);
	if (ret < 0) {
		dev_err(dev, "Failed to read temperature\n");
		goto err_adc;

Annotation

Implementation Notes