On Sun, 17 Nov 2024 18:26:37 +0000
Lothar Rubusch <l.rubusch@xxxxxxxxx> wrote:
> Add the possibility to delay FIFO access when SPI is used. According to
> the datasheet this is needed for the adxl345. When initialization
> happens over SPI the need for delay is to be signalized, and the delay
> will be used.
A specific reference to a section of the specification might be useful
here.
One trivial comment inline, but otherwise looks fine to me.
>
> Signed-off-by: Lothar Rubusch <l.rubusch@xxxxxxxxx>
> ---
> drivers/iio/accel/adxl345.h | 2 +-
> drivers/iio/accel/adxl345_core.c | 6 +++++-
> drivers/iio/accel/adxl345_i2c.c | 2 +-
> drivers/iio/accel/adxl345_spi.c | 3 +++
> 4 files changed, 10 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/iio/accel/adxl345.h b/drivers/iio/accel/adxl345.h
> index cf4132715c..4ba493f636 100644
> --- a/drivers/iio/accel/adxl345.h
> +++ b/drivers/iio/accel/adxl345.h
> @@ -62,7 +62,7 @@ struct adxl345_chip_info {
> };
>
> int adxl345_core_probe(struct device *dev, struct regmap *regmap,
> - int irq,
> + int irq, bool fifo_delay_default,
> 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 902bd3568b..51b229cc44 100644
> --- a/drivers/iio/accel/adxl345_core.c
> +++ b/drivers/iio/accel/adxl345_core.c
> @@ -22,6 +22,7 @@ struct adxl34x_state {
> int irq;
> const struct adxl345_chip_info *info;
> struct regmap *regmap;
> + bool fifo_delay; /* delay: delay is needed for SPI */
> };
>
> #define ADXL345_CHANNEL(index, axis) { \
> @@ -199,13 +200,14 @@ static const struct iio_info adxl345_info = {
> * @dev: Driver model representation of the device
> * @regmap: Regmap instance for the device
> * @irq: Interrupt handling for async usage
> + * @fifo_delay_default: Using FIFO with SPI needs delay
> * @setup: Setup routine to be executed right before the standard device
> * setup
> *
> * Return: 0 on success, negative errno on error
> */
> int adxl345_core_probe(struct device *dev, struct regmap *regmap,
> - int irq,
> + int irq, bool fifo_delay_default,
> int (*setup)(struct device*, struct regmap*))
> {
> struct adxl34x_state *st;
> @@ -234,6 +236,8 @@ int adxl345_core_probe(struct device *dev, struct regmap *regmap,
> if (!st->info)
> return -ENODEV;
>
> + st->fifo_delay = fifo_delay_default;
> +
> indio_dev->name = st->info->name;
> indio_dev->info = &adxl345_info;
> indio_dev->modes = INDIO_DIRECT_MODE;
> diff --git a/drivers/iio/accel/adxl345_i2c.c b/drivers/iio/accel/adxl345_i2c.c
> index 604b706c29..fa1b7e7026 100644
> --- a/drivers/iio/accel/adxl345_i2c.c
> +++ b/drivers/iio/accel/adxl345_i2c.c
> @@ -27,7 +27,7 @@ static int adxl345_i2c_probe(struct i2c_client *client)
> if (IS_ERR(regmap))
> return dev_err_probe(&client->dev, PTR_ERR(regmap), "Error initializing regmap\n");
>
> - return adxl345_core_probe(&client->dev, regmap, client->irq, NULL);
> + return adxl345_core_probe(&client->dev, regmap, client->irq, false, NULL);
> }
>
> static const struct adxl345_chip_info adxl345_i2c_info = {
> diff --git a/drivers/iio/accel/adxl345_spi.c b/drivers/iio/accel/adxl345_spi.c
> index 39e7d71e1d..75940d9c1c 100644
> --- a/drivers/iio/accel/adxl345_spi.c
> +++ b/drivers/iio/accel/adxl345_spi.c
> @@ -12,6 +12,7 @@
> #include "adxl345.h"
>
> #define ADXL345_MAX_SPI_FREQ_HZ 5000000
> +#define ADXL345_MAX_FREQ_NO_FIFO_DELAY 1500000
>
> static const struct regmap_config adxl345_spi_regmap_config = {
> .reg_bits = 8,
> @@ -41,10 +42,12 @@ static int adxl345_spi_probe(struct spi_device *spi)
> if (spi->mode & SPI_3WIRE)
> return adxl345_core_probe(&spi->dev, regmap,
> spi->irq,
> + spi->max_speed_hz > ADXL345_MAX_FREQ_NO_FIFO_DELAY,
> adxl345_spi_setup);
> else
> return adxl345_core_probe(&spi->dev, regmap,
> spi->irq,
> + spi->max_speed_hz > ADXL345_MAX_FREQ_NO_FIFO_DELAY,
use a local variable to establish this without the very long line.
> NULL);
> }
>
