On Fri, 24 Jan 2025 18:27:46 +0000
Sam Winchenbach <swinchenbach@xxxxxxxx> wrote:
> From f851ce8225fc239fcbfc2e06adaa93336a9242ae Mon Sep 17 00:00:00 2001
> From: Sam Winchenbach <swinchenbach@xxxxxxxx>
> Date: Thu, 23 Jan 2025 15:24:09 -0500
> Subject: [PATCH] iio: filter: admv8818: Force initialization of SDO
Hi Sam, we shouldn't be seeing the email header in the patch.
I can tidy that up if you can't fix it though.
>
> When a weak pull-up is present on the SDO line, regmap_update_bits fails
> to write both the SOFTRESET and SDOACTIVE bits because it incorrectly
> reads them as already set.
>
> Since the soft reset disables the SDO line, performing a
> read-modify-write operation on ADI_SPI_CONFIG_A to enable the SDO line
> doesn't make sense. This change directly writes to the register instead
> of using regmap_update_bits.
>
Sounds like a fix, so could you send an appropriate Fixes tag
in a v2 and/or a reply to this email.
> Signed-off-by: Sam Winchenbach <swinchenbach@xxxxxxxx>
> ---
> drivers/iio/filter/admv8818.c | 14 ++++----------
> 1 file changed, 4 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/iio/filter/admv8818.c b/drivers/iio/filter/admv8818.c
> index 195e58bc4..9cd1eee84 100644
> --- a/drivers/iio/filter/admv8818.c
> +++ b/drivers/iio/filter/admv8818.c
> @@ -577,21 +577,15 @@ static int admv8818_init(struct admv8818_state *st)
> struct spi_device *spi = st->spi;
> unsigned int chip_id;
>
> - ret = regmap_update_bits(st->regmap, ADMV8818_REG_SPI_CONFIG_A,
> - ADMV8818_SOFTRESET_N_MSK |
> - ADMV8818_SOFTRESET_MSK,
> - FIELD_PREP(ADMV8818_SOFTRESET_N_MSK, 1) |
> - FIELD_PREP(ADMV8818_SOFTRESET_MSK, 1));
> + ret = regmap_write(st->regmap, ADMV8818_REG_SPI_CONFIG_A,
> + ADMV8818_SOFTRESET_N_MSK | ADMV8818_SOFTRESET_MSK);
> if (ret) {
> dev_err(&spi->dev, "ADMV8818 Soft Reset failed.\n");
> return ret;
> }
>
> - ret = regmap_update_bits(st->regmap, ADMV8818_REG_SPI_CONFIG_A,
> - ADMV8818_SDOACTIVE_N_MSK |
> - ADMV8818_SDOACTIVE_MSK,
> - FIELD_PREP(ADMV8818_SDOACTIVE_N_MSK, 1) |
> - FIELD_PREP(ADMV8818_SDOACTIVE_MSK, 1));
> + ret = regmap_write(st->regmap, ADMV8818_REG_SPI_CONFIG_A,
> + ADMV8818_SDOACTIVE_N_MSK | ADMV8818_SDOACTIVE_MSK);
> if (ret) {
> dev_err(&spi->dev, "ADMV8818 SDO Enable failed.\n");
> return ret;
