[PATCH v3 6/7] iio: accel: kionix-kx022a: Add a function to retrieve number of bytes in buffer

Mehdi Djait
2023-04-24T22:23:29Z

Since Kionix accelerometers use various numbers of bits to report data, a
device-specific function is required.
Implement the function as a callback in the device-specific chip_info structure

Signed-off-by: Mehdi Djait <mehdi.djait.k@gmail.com>
---
v3:
- fixed the warning of the kernel test robot in kx132_get_fifo_bytes
(invalid assignment: &=, left side has type restricted __le16
right side has type unsigned short)

v2:
- mentioned the kx132-1211 in the Kconfig
- added a kx132-specific get_fifo_bytes function
- changed the device name from "kx132" to "kx132-1211

drivers/iio/accel/kionix-kx022a.c | 30 ++++++++++++++++++++----------
drivers/iio/accel/kionix-kx022a.h | 4 ++++
2 files changed, 24 insertions(+), 10 deletions(-)

diff --git a/drivers/iio/accel/kionix-kx022a.c b/drivers/iio/accel/kionix-kx022a.c
index 66da3c8c3fd0..4a31d17c1f22 100644
--- a/drivers/iio/accel/kionix-kx022a.c
+++ b/drivers/iio/accel/kionix-kx022a.c
@@ -595,11 +595,28 @@ static int kx022a_drop_fifo_contents(struct kx022a_data *data)
return regmap_write(data->regmap, data->chip_info->buf_clear, 0x0);
}

+static int kx022a_get_fifo_bytes(struct kx022a_data *data)
+{
+ struct device *dev = regmap_get_device(data->regmap);
+ int ret, fifo_bytes;
+
+ ret = regmap_read(data->regmap, KX022A_REG_BUF_STATUS_1, &fifo_bytes);
+ if (ret) {
+ dev_err(dev, "Error reading buffer status\n");
+ return ret;
+ }
+
+ /* Let's not overflow if we for some reason get bogus value from i2c */
+ if (fifo_bytes == KX022A_FIFO_FULL_VALUE)
+ fifo_bytes = KX022A_FIFO_MAX_BYTES;
+
+ return fifo_bytes;
+}
+
static int __kx022a_fifo_flush(struct iio_dev *idev, unsigned int samples,
bool irq)
{
struct kx022a_data *data = iio_priv(idev);
- struct device *dev = regmap_get_device(data->regmap);
__le16 *buffer;
uint64_t sample_period;
int count, fifo_bytes;
@@ -611,15 +628,7 @@ static int __kx022a_fifo_flush(struct iio_dev *idev, unsigned int samples,
if (!buffer)
return -ENOMEM;

- ret = regmap_read(data->regmap, KX022A_REG_BUF_STATUS_1, &fifo_bytes);
- if (ret) {
- dev_err(dev, "Error reading buffer status\n");
- return ret;
- }
-
- /* Let's not overflow if we for some reason get bogus value from i2c */
- if (fifo_bytes == KX022A_FIFO_FULL_VALUE)
- fifo_bytes = KX022A_FIFO_MAX_BYTES;
+ fifo_bytes = data->chip_info->get_fifo_bytes(data);

if (fifo_bytes % KX022A_FIFO_SAMPLES_SIZE_BYTES)
dev_warn(data->dev, "Bad FIFO alignment. Data may be corrupt\n");
@@ -1023,6 +1032,7 @@ const struct kx022a_chip_info kx022a_chip_info = {
.inc5 = KX022A_REG_INC5,
.inc6 = KX022A_REG_INC6,
.xout_l = KX022A_REG_XOUT_L,
+ .get_fifo_bytes = kx022a_get_fifo_bytes,
};
EXPORT_SYMBOL_NS_GPL(kx022a_chip_info, IIO_KX022A);

diff --git a/drivers/iio/accel/kionix-kx022a.h b/drivers/iio/accel/kionix-kx022a.h
index 3c31e7d88f78..f043767067b7 100644
--- a/drivers/iio/accel/kionix-kx022a.h
+++ b/drivers/iio/accel/kionix-kx022a.h
@@ -76,6 +76,8 @@

struct device;

+struct kx022a_data;
+
/**
* struct kx022a_chip_info - Kionix accelerometer chip specific information
*
@@ -100,6 +102,7 @@ struct device;
* @inc5: interrupt control register 5
* @inc6: interrupt control register 6
* @xout_l: x-axis output least significant byte
+ * @get_fifo_bytes: function pointer to get number of bytes in the FIFO buffer
*/
struct kx022a_chip_info {
const char *name;
@@ -123,6 +126,7 @@ struct kx022a_chip_info {
u8 inc5;
u8 inc6;
u8 xout_l;
+ int (*get_fifo_bytes)(struct kx022a_data *);
};

int kx022a_probe_internal(struct device *dev, const struct kx022a_chip_info *chip_info);
--
2.30.2