[PATCH v2 1/3] iio: accel: adxl345: Update adxl345

From: Lothar Rubusch
Date: Thu Mar 21 2024 - 20:38:10 EST

Move driver wide constants and fields into the header.
Let probe call a separate setup function. Provide
possibility for an SPI/I2C specific setup to be passed
as function pointer to core.

Signed-off-by: Lothar Rubusch <l.rubusch@xxxxxxxxx>
---
drivers/iio/accel/adxl345.h | 44 +++++++++++-
drivers/iio/accel/adxl345_core.c | 117 +++++++++++++++++--------------
drivers/iio/accel/adxl345_i2c.c | 30 ++++----
drivers/iio/accel/adxl345_spi.c | 28 ++++----
4 files changed, 134 insertions(+), 85 deletions(-)

diff --git a/drivers/iio/accel/adxl345.h b/drivers/iio/accel/adxl345.h
index 284bd387c..01493c999 100644
--- a/drivers/iio/accel/adxl345.h
+++ b/drivers/iio/accel/adxl345.h
@@ -8,6 +8,39 @@
#ifndef _ADXL345_H_
#define _ADXL345_H_

+#include <linux/iio/iio.h>
+
+/* ADXL345 register definitions */
+#define ADXL345_REG_DEVID 0x00
+#define ADXL345_REG_OFSX 0x1E
+#define ADXL345_REG_OFSY 0x1F
+#define ADXL345_REG_OFSZ 0x20
+#define ADXL345_REG_OFS_AXIS(index) (ADXL345_REG_OFSX + (index))
+#define ADXL345_REG_BW_RATE 0x2C
+#define ADXL345_REG_POWER_CTL 0x2D
+#define ADXL345_REG_DATA_FORMAT 0x31
+#define ADXL345_REG_DATAX0 0x32
+#define ADXL345_REG_DATAY0 0x34
+#define ADXL345_REG_DATAZ0 0x36
+#define ADXL345_REG_DATA_AXIS(index) \
+ (ADXL345_REG_DATAX0 + (index) * sizeof(__le16))
+
+#define ADXL345_BW_RATE GENMASK(3, 0)
+#define ADXL345_BASE_RATE_NANO_HZ 97656250LL
+
+#define ADXL345_POWER_CTL_MEASURE BIT(3)
+#define ADXL345_POWER_CTL_STANDBY 0x00
+
+#define ADXL345_DATA_FORMAT_FULL_RES BIT(3) /* Up to 13-bits resolution */
+#define ADXL345_DATA_FORMAT_SPI BIT(6) /* spi-3wire */
+#define ADXL345_DATA_FORMAT_2G 0
+#define ADXL345_DATA_FORMAT_4G 1
+#define ADXL345_DATA_FORMAT_8G 2
+#define ADXL345_DATA_FORMAT_16G 3
+#define ADXL345_DATA_FORMAT_MSK ~((u8) BIT(6)) /* ignore spi-3wire */
+
+#define ADXL345_DEVID 0xE5
+
/*
* In full-resolution mode, scale factor is maintained at ~4 mg/LSB
* in all g ranges.
@@ -23,11 +56,20 @@
*/
#define ADXL375_USCALE 480000

+enum adxl345_device_type {
+ ADXL345,
+ ADXL375,
+};
+
struct adxl345_chip_info {
const char *name;
int uscale;
};

-int adxl345_core_probe(struct device *dev, struct regmap *regmap);
+extern const struct adxl345_chip_info adxl3x5_chip_info[];
+
+int adxl345_core_probe(struct device *dev, struct regmap *regmap,
+ const struct adxl345_chip_info *chip_info,
+ int (*setup)(struct device*, struct regmap*));

#endif /* _ADXL345_H_ */
diff --git a/drivers/iio/accel/adxl345_core.c b/drivers/iio/accel/adxl345_core.c
index 8bd30a23e..040c3f05a 100644
--- a/drivers/iio/accel/adxl345_core.c
+++ b/drivers/iio/accel/adxl345_core.c
@@ -17,38 +17,9 @@

#include "adxl345.h"

-#define ADXL345_REG_DEVID 0x00
-#define ADXL345_REG_OFSX 0x1e
-#define ADXL345_REG_OFSY 0x1f
-#define ADXL345_REG_OFSZ 0x20
-#define ADXL345_REG_OFS_AXIS(index) (ADXL345_REG_OFSX + (index))
-#define ADXL345_REG_BW_RATE 0x2C
-#define ADXL345_REG_POWER_CTL 0x2D
-#define ADXL345_REG_DATA_FORMAT 0x31
-#define ADXL345_REG_DATAX0 0x32
-#define ADXL345_REG_DATAY0 0x34
-#define ADXL345_REG_DATAZ0 0x36
-#define ADXL345_REG_DATA_AXIS(index) \
- (ADXL345_REG_DATAX0 + (index) * sizeof(__le16))
-
-#define ADXL345_BW_RATE GENMASK(3, 0)
-#define ADXL345_BASE_RATE_NANO_HZ 97656250LL
-
-#define ADXL345_POWER_CTL_MEASURE BIT(3)
-#define ADXL345_POWER_CTL_STANDBY 0x00
-
-#define ADXL345_DATA_FORMAT_FULL_RES BIT(3) /* Up to 13-bits resolution */
-#define ADXL345_DATA_FORMAT_2G 0
-#define ADXL345_DATA_FORMAT_4G 1
-#define ADXL345_DATA_FORMAT_8G 2
-#define ADXL345_DATA_FORMAT_16G 3
-
-#define ADXL345_DEVID 0xE5
-
struct adxl345_data {
const struct adxl345_chip_info *info;
struct regmap *regmap;
- u8 data_range;
};

#define ADXL345_CHANNEL(index, axis) { \
@@ -62,6 +33,18 @@ struct adxl345_data {
BIT(IIO_CHAN_INFO_SAMP_FREQ), \
}

+const struct adxl345_chip_info adxl3x5_chip_info[] = {
+ [ADXL345] = {
+ .name = "adxl345",
+ .uscale = ADXL345_USCALE,
+ },
+ [ADXL375] = {
+ .name = "adxl375",
+ .uscale = ADXL375_USCALE,
+ },
+};
+EXPORT_SYMBOL_NS_GPL(adxl3x5_chip_info, IIO_ADXL345);
+
static const struct iio_chan_spec adxl345_channels[] = {
ADXL345_CHANNEL(0, X),
ADXL345_CHANNEL(1, Y),
@@ -197,14 +180,21 @@ static void adxl345_powerdown(void *regmap)
regmap_write(regmap, ADXL345_REG_POWER_CTL, ADXL345_POWER_CTL_STANDBY);
}

-int adxl345_core_probe(struct device *dev, struct regmap *regmap)
+static int adxl345_setup(struct device *dev, struct adxl345_data *data,
+ int (*setup)(struct device*, struct regmap*))
{
- struct adxl345_data *data;
- struct iio_dev *indio_dev;
u32 regval;
int ret;

- ret = regmap_read(regmap, ADXL345_REG_DEVID, &regval);
+ /* Perform bus specific settings if available */
+ if (setup) {
+ ret = setup(dev, data->regmap);
+ if (ret)
+ return ret;
+ }
+
+ /* Read out DEVID */
+ ret = regmap_read(data->regmap, ADXL345_REG_DEVID, &regval);
if (ret < 0)
return dev_err_probe(dev, ret, "Error reading device ID\n");

@@ -212,37 +202,62 @@ int adxl345_core_probe(struct device *dev, struct regmap *regmap)
return dev_err_probe(dev, -ENODEV, "Invalid device ID: %x, expected %x\n",
regval, ADXL345_DEVID);

+ /* Update data_format to full-resolution mode */
+ ret = regmap_update_bits(data->regmap, ADXL345_REG_DATA_FORMAT,
+ ADXL345_DATA_FORMAT_MSK, ADXL345_DATA_FORMAT_FULL_RES);
+ if (ret)
+ return dev_err_probe(dev, ret, "Failed to update data_format register\n");
+
+ /* Enable measurement mode */
+ ret = adxl345_powerup(data->regmap);
+ if (ret < 0)
+ return dev_err_probe(dev, ret, "Failed to enable measurement mode\n");
+
+ ret = devm_add_action_or_reset(dev, adxl345_powerdown, data->regmap);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+/**
+ * adxl345_core_probe() - probe and setup for the adxl345 accelerometer,
+ * also covers the adlx375 accelerometer
+ * @dev: Driver model representation of the device
+ * @regmap: Regmap instance for the device
+ * @chip_info: Structure containing device specific data
+ * @setup: Setup routine to be executed right before the standard device
+ * setup, can also be set to NULL if not required
+ *
+ * Return: 0 on success, negative errno on error
+ */
+int adxl345_core_probe(struct device *dev, struct regmap *regmap,
+ const struct adxl345_chip_info *chip_info,
+ int (*setup)(struct device*, struct regmap*))
+{
+ struct adxl345_data *data;
+ struct iio_dev *indio_dev;
+ int ret;
+
indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
if (!indio_dev)
return -ENOMEM;

data = iio_priv(indio_dev);
data->regmap = regmap;
- /* Enable full-resolution mode */
- data->data_range = ADXL345_DATA_FORMAT_FULL_RES;
- data->info = device_get_match_data(dev);
- if (!data->info)
- return -ENODEV;
-
- ret = regmap_write(data->regmap, ADXL345_REG_DATA_FORMAT,
- data->data_range);
- if (ret < 0)
- return dev_err_probe(dev, ret, "Failed to set data range\n");
+ data->info = chip_info;

- indio_dev->name = data->info->name;
+ indio_dev->name = chip_info->name;
indio_dev->info = &adxl345_info;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->channels = adxl345_channels;
indio_dev->num_channels = ARRAY_SIZE(adxl345_channels);

- /* Enable measurement mode */
- ret = adxl345_powerup(data->regmap);
- if (ret < 0)
- return dev_err_probe(dev, ret, "Failed to enable measurement mode\n");
-
- ret = devm_add_action_or_reset(dev, adxl345_powerdown, data->regmap);
- if (ret < 0)
+ ret = adxl345_setup(dev, data, setup);
+ if (ret) {
+ dev_err(dev, "ADXL345 setup failed\n");
return ret;
+ }

return devm_iio_device_register(dev, indio_dev);
}
diff --git a/drivers/iio/accel/adxl345_i2c.c b/drivers/iio/accel/adxl345_i2c.c
index a3084b0a8..3f882e2e0 100644
--- a/drivers/iio/accel/adxl345_i2c.c
+++ b/drivers/iio/accel/adxl345_i2c.c
@@ -9,6 +9,7 @@
*/

#include <linux/i2c.h>
+#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/regmap.h>

@@ -21,41 +22,36 @@ static const struct regmap_config adxl345_i2c_regmap_config = {

static int adxl345_i2c_probe(struct i2c_client *client)
{
+ const struct adxl345_chip_info *chip_data;
struct regmap *regmap;

+ /* Retrieve device data, i.e. the name, to pass it to the core */
+ chip_data = i2c_get_match_data(client);
+
regmap = devm_regmap_init_i2c(client, &adxl345_i2c_regmap_config);
if (IS_ERR(regmap))
- return dev_err_probe(&client->dev, PTR_ERR(regmap), "Error initializing regmap\n");
+ return dev_err_probe(&client->dev, PTR_ERR(regmap),
+ "Error initializing regmap\n");

- return adxl345_core_probe(&client->dev, regmap);
+ return adxl345_core_probe(&client->dev, regmap, chip_data, NULL);
}

-static const struct adxl345_chip_info adxl345_i2c_info = {
- .name = "adxl345",
- .uscale = ADXL345_USCALE,
-};
-
-static const struct adxl345_chip_info adxl375_i2c_info = {
- .name = "adxl375",
- .uscale = ADXL375_USCALE,
-};
-
static const struct i2c_device_id adxl345_i2c_id[] = {
- { "adxl345", (kernel_ulong_t)&adxl345_i2c_info },
- { "adxl375", (kernel_ulong_t)&adxl375_i2c_info },
+ { "adxl345", (kernel_ulong_t)&adxl3x5_chip_info[ADXL345] },
+ { "adxl375", (kernel_ulong_t)&adxl3x5_chip_info[ADXL375] },
{ }
};
MODULE_DEVICE_TABLE(i2c, adxl345_i2c_id);

static const struct of_device_id adxl345_of_match[] = {
- { .compatible = "adi,adxl345", .data = &adxl345_i2c_info },
- { .compatible = "adi,adxl375", .data = &adxl375_i2c_info },
+ { .compatible = "adi,adxl345", .data = &adxl3x5_chip_info[ADXL345] },
+ { .compatible = "adi,adxl375", .data = &adxl3x5_chip_info[ADXL375] },
{ }
};
MODULE_DEVICE_TABLE(of, adxl345_of_match);

static const struct acpi_device_id adxl345_acpi_match[] = {
- { "ADS0345", (kernel_ulong_t)&adxl345_i2c_info },
+ { "ADS0345", (kernel_ulong_t)&adxl3x5_chip_info[ADXL345] },
{ }
};
MODULE_DEVICE_TABLE(acpi, adxl345_acpi_match);
diff --git a/drivers/iio/accel/adxl345_spi.c b/drivers/iio/accel/adxl345_spi.c
index 93ca349f1..c26bac462 100644
--- a/drivers/iio/accel/adxl345_spi.c
+++ b/drivers/iio/accel/adxl345_spi.c
@@ -22,8 +22,14 @@ static const struct regmap_config adxl345_spi_regmap_config = {

static int adxl345_spi_probe(struct spi_device *spi)
{
+ const struct adxl345_chip_info *chip_data;
struct regmap *regmap;

+ /* Retrieve device name to pass it as driver specific data */
+ chip_data = device_get_match_data(&spi->dev);
+ if (!chip_data)
+ chip_data = spi_get_device_match_data(spi);
+
/* Bail out if max_speed_hz exceeds 5 MHz */
if (spi->max_speed_hz > ADXL345_MAX_SPI_FREQ_HZ)
return dev_err_probe(&spi->dev, -EINVAL, "SPI CLK, %d Hz exceeds 5 MHz\n",
@@ -33,35 +39,25 @@ static int adxl345_spi_probe(struct spi_device *spi)
if (IS_ERR(regmap))
return dev_err_probe(&spi->dev, PTR_ERR(regmap), "Error initializing regmap\n");

- return adxl345_core_probe(&spi->dev, regmap);
+ return adxl345_core_probe(&spi->dev, regmap, chip_data, NULL);
}

-static const struct adxl345_chip_info adxl345_spi_info = {
- .name = "adxl345",
- .uscale = ADXL345_USCALE,
-};
-
-static const struct adxl345_chip_info adxl375_spi_info = {
- .name = "adxl375",
- .uscale = ADXL375_USCALE,
-};
-
static const struct spi_device_id adxl345_spi_id[] = {
- { "adxl345", (kernel_ulong_t)&adxl345_spi_info },
- { "adxl375", (kernel_ulong_t)&adxl375_spi_info },
+ { "adxl345", (kernel_ulong_t)&adxl3x5_chip_info[ADXL345] },
+ { "adxl375", (kernel_ulong_t)&adxl3x5_chip_info[ADXL375] },
{ }
};
MODULE_DEVICE_TABLE(spi, adxl345_spi_id);

static const struct of_device_id adxl345_of_match[] = {
- { .compatible = "adi,adxl345", .data = &adxl345_spi_info },
- { .compatible = "adi,adxl375", .data = &adxl375_spi_info },
+ { .compatible = "adi,adxl345", .data = &adxl3x5_chip_info[ADXL345] },
+ { .compatible = "adi,adxl375", .data = &adxl3x5_chip_info[ADXL375] },
{ }
};
MODULE_DEVICE_TABLE(of, adxl345_of_match);

static const struct acpi_device_id adxl345_acpi_match[] = {
- { "ADS0345", (kernel_ulong_t)&adxl345_spi_info },
+ { "ADS0345", (kernel_ulong_t)&adxl3x5_chip_info[ADXL345] },
{ }
};
MODULE_DEVICE_TABLE(acpi, adxl345_acpi_match);
--
2.25.1