Re: [PATCH 3/5] iio: imu: adis: Add support for SPI transfer cs_change_stall_delay_us

From: Jonathan Cameron
Date: Wed Jun 26 2019 - 14:35:50 EST


On Tue, 25 Jun 2019 16:13:26 +0300
Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx> wrote:

> The ADIS16460 requires a higher delay before the next transfer. Since the
> SPI framework supports configuring the delay before the next transfer, this
> driver will become the first user of it.
>
> The support for this functionality in ADIS16460 requires an addition to the
> ADIS lib to support the `cs_change_stall_delay_us` functionality in SPI.
>
> Signed-off-by: Michael Hennerich <michael.hennerich@xxxxxxxxxx>
> Signed-off-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>
Subject to previous patch naming etc, this is fine and I'll pick it up once
that's sorted.

Thanks,

Jonathan

> ---
> drivers/iio/imu/adis.c | 9 +++++++++
> include/linux/iio/imu/adis.h | 2 ++
> 2 files changed, 11 insertions(+)
>
> diff --git a/drivers/iio/imu/adis.c b/drivers/iio/imu/adis.c
> index c771ae6803a9..90dac69910b3 100644
> --- a/drivers/iio/imu/adis.c
> +++ b/drivers/iio/imu/adis.c
> @@ -40,28 +40,33 @@ int adis_write_reg(struct adis *adis, unsigned int reg,
> .len = 2,
> .cs_change = 1,
> .delay_usecs = adis->data->write_delay,
> + .cs_change_stall_delay_us = adis->data->cs_stall_delay,
> }, {
> .tx_buf = adis->tx + 2,
> .bits_per_word = 8,
> .len = 2,
> .cs_change = 1,
> .delay_usecs = adis->data->write_delay,
> + .cs_change_stall_delay_us = adis->data->cs_stall_delay,
> }, {
> .tx_buf = adis->tx + 4,
> .bits_per_word = 8,
> .len = 2,
> .cs_change = 1,
> .delay_usecs = adis->data->write_delay,
> + .cs_change_stall_delay_us = adis->data->cs_stall_delay,
> }, {
> .tx_buf = adis->tx + 6,
> .bits_per_word = 8,
> .len = 2,
> .delay_usecs = adis->data->write_delay,
> + .cs_change_stall_delay_us = adis->data->cs_stall_delay,
> }, {
> .tx_buf = adis->tx + 8,
> .bits_per_word = 8,
> .len = 2,
> .delay_usecs = adis->data->write_delay,
> + .cs_change_stall_delay_us = adis->data->cs_stall_delay,
> },
> };
>
> @@ -134,12 +139,14 @@ int adis_read_reg(struct adis *adis, unsigned int reg,
> .len = 2,
> .cs_change = 1,
> .delay_usecs = adis->data->write_delay,
> + .cs_change_stall_delay_us = adis->data->cs_stall_delay,
> }, {
> .tx_buf = adis->tx + 2,
> .bits_per_word = 8,
> .len = 2,
> .cs_change = 1,
> .delay_usecs = adis->data->read_delay,
> + .cs_change_stall_delay_us = adis->data->cs_stall_delay,
> }, {
> .tx_buf = adis->tx + 4,
> .rx_buf = adis->rx,
> @@ -147,11 +154,13 @@ int adis_read_reg(struct adis *adis, unsigned int reg,
> .len = 2,
> .cs_change = 1,
> .delay_usecs = adis->data->read_delay,
> + .cs_change_stall_delay_us = adis->data->cs_stall_delay,
> }, {
> .rx_buf = adis->rx + 2,
> .bits_per_word = 8,
> .len = 2,
> .delay_usecs = adis->data->read_delay,
> + .cs_change_stall_delay_us = adis->data->cs_stall_delay,
> },
> };
>
> diff --git a/include/linux/iio/imu/adis.h b/include/linux/iio/imu/adis.h
> index 469a493f7ae0..4aa248b6b3bd 100644
> --- a/include/linux/iio/imu/adis.h
> +++ b/include/linux/iio/imu/adis.h
> @@ -27,6 +27,7 @@ struct adis_burst;
> * struct adis_data - ADIS chip variant specific data
> * @read_delay: SPI delay for read operations in us
> * @write_delay: SPI delay for write operations in us
> + * @cs_stall_delay: SPI stall delay between transfers in us
> * @glob_cmd_reg: Register address of the GLOB_CMD register
> * @msc_ctrl_reg: Register address of the MSC_CTRL register
> * @diag_stat_reg: Register address of the DIAG_STAT register
> @@ -36,6 +37,7 @@ struct adis_burst;
> struct adis_data {
> unsigned int read_delay;
> unsigned int write_delay;
> + unsigned int cs_stall_delay;
>
> unsigned int glob_cmd_reg;
> unsigned int msc_ctrl_reg;