[PATCH v2 3/3] iio: accel: st_accel: Add support for Silan SC7A20

Samuel Holland
2022-02-02T23:51:07Z

This chip appears to be register-compatible with the LIS2DH. The new
description is a copy of the LIS2DH's description with a different WAI
value.

Datasheet: http://linux-chenxing.org/silan/SC7A20-SilanMicroelectronics.pdf
Datasheet: http://www.siitek.com.cn/Upfiles/down/SC7A20说明书_0.92(智能穿戴).pdf
Signed-off-by: Samuel Holland <samuel@sholland.org>
---

Changes in v2:
- Add a comment about the WAI value
- Update commit messages

drivers/iio/accel/st_accel.h | 2 +
drivers/iio/accel/st_accel_core.c | 83 +++++++++++++++++++++++++++++++
drivers/iio/accel/st_accel_i2c.c | 5 ++
3 files changed, 90 insertions(+)

diff --git a/drivers/iio/accel/st_accel.h b/drivers/iio/accel/st_accel.h
index 8750dea56fcb..00e056c21bfc 100644
--- a/drivers/iio/accel/st_accel.h
+++ b/drivers/iio/accel/st_accel.h
@@ -36,6 +36,7 @@ enum st_accel_type {
LIS3DHH,
LIS2DE12,
LIS2HH12,
+ SC7A20,
ST_ACCEL_MAX,
};

@@ -61,6 +62,7 @@ enum st_accel_type {
#define LIS3DE_ACCEL_DEV_NAME "lis3de"
#define LIS2DE12_ACCEL_DEV_NAME "lis2de12"
#define LIS2HH12_ACCEL_DEV_NAME "lis2hh12"
+#define SC7A20_ACCEL_DEV_NAME "sc7a20"

#ifdef CONFIG_IIO_BUFFER
int st_accel_allocate_ring(struct iio_dev *indio_dev);
diff --git a/drivers/iio/accel/st_accel_core.c b/drivers/iio/accel/st_accel_core.c
index 31ea19d0ba71..2ada8d6fb503 100644
--- a/drivers/iio/accel/st_accel_core.c
+++ b/drivers/iio/accel/st_accel_core.c
@@ -1087,6 +1087,89 @@ static const struct st_sensor_settings st_accel_sensors_settings[] = {
.multi_read_bit = true,
.bootime = 2,
},
+ {
+ /*
+ * Not an ST part. Register-compatible with the LIS2DH, even
+ * though the WAI value is different.
+ */
+ .wai = 0x11,
+ .wai_addr = ST_SENSORS_DEFAULT_WAI_ADDRESS,
+ .sensors_supported = {
+ [0] = SC7A20_ACCEL_DEV_NAME,
+ },
+ .ch = (struct iio_chan_spec *)st_accel_12bit_channels,
+ .odr = {
+ .addr = 0x20,
+ .mask = 0xf0,
+ .odr_avl = {
+ { .hz = 1, .value = 0x01, },
+ { .hz = 10, .value = 0x02, },
+ { .hz = 25, .value = 0x03, },
+ { .hz = 50, .value = 0x04, },
+ { .hz = 100, .value = 0x05, },
+ { .hz = 200, .value = 0x06, },
+ { .hz = 400, .value = 0x07, },
+ { .hz = 1600, .value = 0x08, },
+ },
+ },
+ .pw = {
+ .addr = 0x20,
+ .mask = 0xf0,
+ .value_off = ST_SENSORS_DEFAULT_POWER_OFF_VALUE,
+ },
+ .enable_axis = {
+ .addr = ST_SENSORS_DEFAULT_AXIS_ADDR,
+ .mask = ST_SENSORS_DEFAULT_AXIS_MASK,
+ },
+ .fs = {
+ .addr = 0x23,
+ .mask = 0x30,
+ .fs_avl = {
+ [0] = {
+ .num = ST_ACCEL_FS_AVL_2G,
+ .value = 0x00,
+ .gain = IIO_G_TO_M_S_2(1000),
+ },
+ [1] = {
+ .num = ST_ACCEL_FS_AVL_4G,
+ .value = 0x01,
+ .gain = IIO_G_TO_M_S_2(2000),
+ },
+ [2] = {
+ .num = ST_ACCEL_FS_AVL_8G,
+ .value = 0x02,
+ .gain = IIO_G_TO_M_S_2(4000),
+ },
+ [3] = {
+ .num = ST_ACCEL_FS_AVL_16G,
+ .value = 0x03,
+ .gain = IIO_G_TO_M_S_2(12000),
+ },
+ },
+ },
+ .bdu = {
+ .addr = 0x23,
+ .mask = 0x80,
+ },
+ .drdy_irq = {
+ .int1 = {
+ .addr = 0x22,
+ .mask = 0x10,
+ },
+ .addr_ihl = 0x25,
+ .mask_ihl = 0x02,
+ .stat_drdy = {
+ .addr = ST_SENSORS_DEFAULT_STAT_ADDR,
+ .mask = 0x07,
+ },
+ },
+ .sim = {
+ .addr = 0x23,
+ .value = BIT(0),
+ },
+ .multi_read_bit = true,
+ .bootime = 2,
+ },
};

/* Default accel DRDY is available on INT1 pin */
diff --git a/drivers/iio/accel/st_accel_i2c.c b/drivers/iio/accel/st_accel_i2c.c
index c0ce78eebad9..7f5888570e87 100644
--- a/drivers/iio/accel/st_accel_i2c.c
+++ b/drivers/iio/accel/st_accel_i2c.c
@@ -107,6 +107,10 @@ static const struct of_device_id st_accel_of_match[] = {
.compatible = "st,lis2hh12",
.data = LIS2HH12_ACCEL_DEV_NAME,
},
+ {
+ .compatible = "silan,sc7a20",
+ .data = SC7A20_ACCEL_DEV_NAME,
+ },
{},
};
MODULE_DEVICE_TABLE(of, st_accel_of_match);
@@ -142,6 +146,7 @@ static const struct i2c_device_id st_accel_id_table[] = {
{ LIS3DE_ACCEL_DEV_NAME },
{ LIS2DE12_ACCEL_DEV_NAME },
{ LIS2HH12_ACCEL_DEV_NAME },
+ { SC7A20_ACCEL_DEV_NAME },
{},
};
MODULE_DEVICE_TABLE(i2c, st_accel_id_table);
--
2.33.1