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Message-ID: <20230924153958.56755045@jic23-huawei>
Date: Sun, 24 Sep 2023 15:39:58 +0100
From: Jonathan Cameron <jic23@...nel.org>
To: alisadariana@...il.com
Cc: Alisa-Dariana Roman <alisa.roman@...log.com>,
Lars-Peter Clausen <lars@...afoo.de>,
Alexandru Tachici <alexandru.tachici@...log.com>,
Michael Hennerich <Michael.Hennerich@...log.com>,
linux-iio@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v2 1/3] iio: adc: ad7192: Use bitfield access macros
On Wed, 20 Sep 2023 03:33:40 +0300
alisadariana@...il.com wrote:
> From: Alisa-Dariana Roman <alisadariana@...il.com>
>
> Include bitfield.h and update driver to use bitfield access macros
> GENMASK, FIELD_PREP and FIELD_GET.
>
> Remove old macros in favor of using FIELD_PREP and masks.
>
> Signed-off-by: Alisa-Dariana Roman <alisa.roman@...log.com>
Hi Alisa-Darinana,
Please fix the author for these to match your sign off
git commit --amend --author="Alisa-Dariana Roman <alisa.roman@...log.com>"
should fix that up.
There are a few interesting corners in the original code where a single
macro was used for the get and set paths. I think a few places you picked
the one with the wrong semantics whilst cleaning it up.
Also some unnecessary !! horribleness now we are extracting the value rather
than a shifted version of the value.
Thanks,
Jonathan
> ---
> drivers/iio/adc/ad7192.c | 73 ++++++++++++++++++++--------------------
> 1 file changed, 37 insertions(+), 36 deletions(-)
>
> diff --git a/drivers/iio/adc/ad7192.c b/drivers/iio/adc/ad7192.c
> index 69d1103b9508..64bc09ce3cb1 100644
> --- a/drivers/iio/adc/ad7192.c
> +++ b/drivers/iio/adc/ad7192.c
> @@ -6,6 +6,7 @@
> */
>
> #include <linux/interrupt.h>
> +#include <linux/bitfield.h>
> #include <linux/clk.h>
> #include <linux/device.h>
> #include <linux/kernel.h>
> @@ -43,7 +44,7 @@
> #define AD7192_COMM_WEN BIT(7) /* Write Enable */
> #define AD7192_COMM_WRITE 0 /* Write Operation */
> #define AD7192_COMM_READ BIT(6) /* Read Operation */
> -#define AD7192_COMM_ADDR(x) (((x) & 0x7) << 3) /* Register Address */
> +#define AD7192_COMM_ADDR_MASK GENMASK(5, 3) /* Register Address Mask */
> #define AD7192_COMM_CREAD BIT(2) /* Continuous Read of Data Register */
>
> /* Status Register Bit Designations (AD7192_REG_STAT) */
> @@ -56,17 +57,16 @@
> #define AD7192_STAT_CH1 BIT(0) /* Channel 1 */
>
> /* Mode Register Bit Designations (AD7192_REG_MODE) */
> -#define AD7192_MODE_SEL(x) (((x) & 0x7) << 21) /* Operation Mode Select */
> -#define AD7192_MODE_SEL_MASK (0x7 << 21) /* Operation Mode Select Mask */
> -#define AD7192_MODE_STA(x) (((x) & 0x1) << 20) /* Status Register transmission */
> +#define AD7192_MODE_SEL_MASK GENMASK(23, 21) /* Operation Mode Select Mask */
> #define AD7192_MODE_STA_MASK BIT(20) /* Status Register transmission Mask */
> -#define AD7192_MODE_CLKSRC(x) (((x) & 0x3) << 18) /* Clock Source Select */
> +#define AD7192_MODE_CLKSRC_MASK GENMASK(19, 18) /* Clock Source Select Mask */
> #define AD7192_MODE_SINC3 BIT(15) /* SINC3 Filter Select */
> #define AD7192_MODE_ENPAR BIT(13) /* Parity Enable */
> #define AD7192_MODE_CLKDIV BIT(12) /* Clock divide by 2 (AD7190/2 only)*/
> #define AD7192_MODE_SCYCLE BIT(11) /* Single cycle conversion */
> #define AD7192_MODE_REJ60 BIT(10) /* 50/60Hz notch filter */
> -#define AD7192_MODE_RATE(x) ((x) & 0x3FF) /* Filter Update Rate Select */
> +#define AD7192_MODE_RATE_MASK GENMASK(9, 0)
> + /* Filter Update Rate Select Mask */
Put the comment on the line above the thing it is talking about, not the line below.
>
> /* Mode Register: AD7192_MODE_SEL options */
> #define AD7192_MODE_CONT 0 /* Continuous Conversion Mode */
> @@ -92,13 +92,12 @@
> #define AD7192_CONF_CHOP BIT(23) /* CHOP enable */
> #define AD7192_CONF_ACX BIT(22) /* AC excitation enable(AD7195 only) */
> #define AD7192_CONF_REFSEL BIT(20) /* REFIN1/REFIN2 Reference Select */
> -#define AD7192_CONF_CHAN(x) ((x) << 8) /* Channel select */
> -#define AD7192_CONF_CHAN_MASK (0x7FF << 8) /* Channel select mask */
> +#define AD7192_CONF_CHAN_MASK GENMASK(18, 8) /* Channel select mask */
> #define AD7192_CONF_BURN BIT(7) /* Burnout current enable */
> #define AD7192_CONF_REFDET BIT(6) /* Reference detect enable */
> #define AD7192_CONF_BUF BIT(4) /* Buffered Mode Enable */
> #define AD7192_CONF_UNIPOLAR BIT(3) /* Unipolar/Bipolar Enable */
> -#define AD7192_CONF_GAIN(x) ((x) & 0x7) /* Gain Select */
> +#define AD7192_CONF_GAIN_MASK GENMASK(2, 0) /* Gain Select */
>
> #define AD7192_CH_AIN1P_AIN2M BIT(0) /* AIN1(+) - AIN2(-) */
> #define AD7192_CH_AIN3P_AIN4M BIT(1) /* AIN3(+) - AIN4(-) */
> @@ -130,7 +129,7 @@
> #define CHIPID_AD7192 0x0
> #define CHIPID_AD7193 0x2
> #define CHIPID_AD7195 0x6
> -#define AD7192_ID_MASK 0x0F
> +#define AD7192_ID_MASK GENMASK(3, 0)
>
> /* GPOCON Register Bit Designations (AD7192_REG_GPOCON) */
> #define AD7192_GPOCON_BPDSW BIT(6) /* Bridge power-down switch enable */
> @@ -272,7 +271,7 @@ static int ad7192_set_channel(struct ad_sigma_delta *sd, unsigned int channel)
> struct ad7192_state *st = ad_sigma_delta_to_ad7192(sd);
>
> st->conf &= ~AD7192_CONF_CHAN_MASK;
> - st->conf |= AD7192_CONF_CHAN(channel);
> + st->conf |= FIELD_PREP(AD7192_CONF_CHAN_MASK, channel);
>
> return ad_sd_write_reg(&st->sd, AD7192_REG_CONF, 3, st->conf);
> }
> @@ -283,7 +282,7 @@ static int ad7192_set_mode(struct ad_sigma_delta *sd,
> struct ad7192_state *st = ad_sigma_delta_to_ad7192(sd);
>
> st->mode &= ~AD7192_MODE_SEL_MASK;
> - st->mode |= AD7192_MODE_SEL(mode);
> + st->mode |= FIELD_PREP(AD7192_MODE_SEL_MASK, mode);
>
> return ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode);
> }
> @@ -295,7 +294,7 @@ static int ad7192_append_status(struct ad_sigma_delta *sd, bool append)
> int ret;
>
> mode &= ~AD7192_MODE_STA_MASK;
> - mode |= AD7192_MODE_STA(append);
> + mode |= FIELD_PREP(AD7192_MODE_STA_MASK, append);
>
> ret = ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, mode);
> if (ret < 0)
> @@ -399,17 +398,17 @@ static int ad7192_setup(struct iio_dev *indio_dev, struct device_node *np)
> if (ret)
> return ret;
>
> - id &= AD7192_ID_MASK;
> + id = FIELD_GET(AD7192_ID_MASK, id);
>
> if (id != st->chip_info->chip_id)
> dev_warn(&st->sd.spi->dev, "device ID query failed (0x%X != 0x%X)\n",
> id, st->chip_info->chip_id);
>
> - st->mode = AD7192_MODE_SEL(AD7192_MODE_IDLE) |
> - AD7192_MODE_CLKSRC(st->clock_sel) |
> - AD7192_MODE_RATE(480);
> + st->mode = FIELD_PREP(AD7192_MODE_SEL_MASK, AD7192_MODE_IDLE) |
> + FIELD_PREP(AD7192_MODE_CLKSRC_MASK, st->clock_sel) |
> + FIELD_PREP(AD7192_MODE_RATE_MASK, 480);
>
> - st->conf = AD7192_CONF_GAIN(0);
> + st->conf = FIELD_PREP(AD7192_CONF_GAIN_MASK, 0);
>
> rej60_en = of_property_read_bool(np, "adi,rejection-60-Hz-enable");
> if (rej60_en)
> @@ -455,7 +454,7 @@ static int ad7192_setup(struct iio_dev *indio_dev, struct device_node *np)
> for (i = 0; i < ARRAY_SIZE(st->scale_avail); i++) {
> scale_uv = ((u64)st->int_vref_mv * 100000000)
> >> (indio_dev->channels[0].scan_type.realbits -
> - ((st->conf & AD7192_CONF_UNIPOLAR) ? 0 : 1));
> + !FIELD_GET(AD7192_CONF_UNIPOLAR, st->conf));
> scale_uv >>= i;
>
> st->scale_avail[i][1] = do_div(scale_uv, 100000000) * 10;
> @@ -472,7 +471,7 @@ static ssize_t ad7192_show_ac_excitation(struct device *dev,
> struct iio_dev *indio_dev = dev_to_iio_dev(dev);
> struct ad7192_state *st = iio_priv(indio_dev);
>
> - return sysfs_emit(buf, "%d\n", !!(st->conf & AD7192_CONF_ACX));
> + return sysfs_emit(buf, "%d\n", !!FIELD_GET(AD7192_CONF_ACX, st->conf));
Can drop the !! as FIELD_GET() will shift it so the value is 0 or 1 anyway.
> }
>
> static ssize_t ad7192_show_bridge_switch(struct device *dev,
> @@ -482,7 +481,8 @@ static ssize_t ad7192_show_bridge_switch(struct device *dev,
> struct iio_dev *indio_dev = dev_to_iio_dev(dev);
> struct ad7192_state *st = iio_priv(indio_dev);
>
> - return sysfs_emit(buf, "%d\n", !!(st->gpocon & AD7192_GPOCON_BPDSW));
> + return sysfs_emit(buf, "%d\n",
> + !!FIELD_GET(AD7192_GPOCON_BPDSW, st->gpocon));
Drop the !!
> }
>
> static ssize_t ad7192_set(struct device *dev,
> @@ -537,14 +537,14 @@ static void ad7192_get_available_filter_freq(struct ad7192_state *st,
>
> /* Formulas for filter at page 25 of the datasheet */
> fadc = DIV_ROUND_CLOSEST(st->fclk,
> - AD7192_SYNC4_FILTER * AD7192_MODE_RATE(st->mode));
> + AD7192_SYNC4_FILTER * FIELD_PREP(AD7192_MODE_RATE_MASK, st->mode));
FIELD_GET()
> freq[0] = DIV_ROUND_CLOSEST(fadc * 240, 1024);
>
> fadc = DIV_ROUND_CLOSEST(st->fclk,
> - AD7192_SYNC3_FILTER * AD7192_MODE_RATE(st->mode));
> + AD7192_SYNC3_FILTER * FIELD_PREP(AD7192_MODE_RATE_MASK, st->mode));
FIELD_GET()
> freq[1] = DIV_ROUND_CLOSEST(fadc * 240, 1024);
>
> - fadc = DIV_ROUND_CLOSEST(st->fclk, AD7192_MODE_RATE(st->mode));
> + fadc = DIV_ROUND_CLOSEST(st->fclk, FIELD_PREP(AD7192_MODE_RATE_MASK, st->mode));
As below FIELD_GET()
> freq[2] = DIV_ROUND_CLOSEST(fadc * 230, 1024);
> freq[3] = DIV_ROUND_CLOSEST(fadc * 272, 1024);
> }
> @@ -665,11 +665,11 @@ static int ad7192_get_3db_filter_freq(struct ad7192_state *st)
> unsigned int fadc;
>
> fadc = DIV_ROUND_CLOSEST(st->fclk,
> - st->f_order * AD7192_MODE_RATE(st->mode));
> + st->f_order * FIELD_PREP(AD7192_MODE_RATE_MASK, st->mode));
As below. I think this should be a FIELD_GET()
>
> - if (st->conf & AD7192_CONF_CHOP)
> + if (FIELD_GET(AD7192_CONF_CHOP, st->conf))
> return DIV_ROUND_CLOSEST(fadc * 240, 1024);
> - if (st->mode & AD7192_MODE_SINC3)
> + if (FIELD_GET(AD7192_MODE_SINC3, st->mode))
> return DIV_ROUND_CLOSEST(fadc * 272, 1024);
> else
> return DIV_ROUND_CLOSEST(fadc * 230, 1024);
> @@ -682,7 +682,8 @@ static int ad7192_read_raw(struct iio_dev *indio_dev,
> long m)
> {
> struct ad7192_state *st = iio_priv(indio_dev);
> - bool unipolar = !!(st->conf & AD7192_CONF_UNIPOLAR);
> + bool unipolar = !!FIELD_GET(AD7192_CONF_UNIPOLAR, st->conf);
> + u8 gain = FIELD_PREP(AD7192_CONF_GAIN_MASK, st->conf);
>
> switch (m) {
> case IIO_CHAN_INFO_RAW:
> @@ -691,8 +692,8 @@ static int ad7192_read_raw(struct iio_dev *indio_dev,
> switch (chan->type) {
> case IIO_VOLTAGE:
> mutex_lock(&st->lock);
> - *val = st->scale_avail[AD7192_CONF_GAIN(st->conf)][0];
> - *val2 = st->scale_avail[AD7192_CONF_GAIN(st->conf)][1];
> + *val = st->scale_avail[gain][0];
> + *val2 = st->scale_avail[gain][1];
> mutex_unlock(&st->lock);
> return IIO_VAL_INT_PLUS_NANO;
> case IIO_TEMP:
> @@ -713,7 +714,7 @@ static int ad7192_read_raw(struct iio_dev *indio_dev,
> return IIO_VAL_INT;
> case IIO_CHAN_INFO_SAMP_FREQ:
> *val = st->fclk /
> - (st->f_order * 1024 * AD7192_MODE_RATE(st->mode));
> + (st->f_order * 1024 * FIELD_PREP(AD7192_MODE_RATE_MASK, st->mode));
FIELD_GET() I think. Though not 100% sure of intent and as it just masks
it isn't a code change to flip from one to the other.
> return IIO_VAL_INT;
> case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
> *val = ad7192_get_3db_filter_freq(st);
> @@ -746,8 +747,8 @@ static int ad7192_write_raw(struct iio_dev *indio_dev,
> if (val2 == st->scale_avail[i][1]) {
> ret = 0;
> tmp = st->conf;
> - st->conf &= ~AD7192_CONF_GAIN(-1);
> - st->conf |= AD7192_CONF_GAIN(i);
> + st->conf &= ~AD7192_CONF_GAIN_MASK;
> + st->conf |= FIELD_PREP(AD7192_CONF_GAIN_MASK, i);
> if (tmp == st->conf)
> break;
> ad_sd_write_reg(&st->sd, AD7192_REG_CONF,
> @@ -769,8 +770,8 @@ static int ad7192_write_raw(struct iio_dev *indio_dev,
> break;
> }
>
> - st->mode &= ~AD7192_MODE_RATE(-1);
> - st->mode |= AD7192_MODE_RATE(div);
> + st->mode &= ~AD7192_MODE_RATE_MASK;
> + st->mode |= FIELD_PREP(AD7192_MODE_RATE_MASK, div);
> ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode);
> break;
> case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
> @@ -830,7 +831,7 @@ static int ad7192_update_scan_mode(struct iio_dev *indio_dev, const unsigned lon
>
> conf &= ~AD7192_CONF_CHAN_MASK;
> for_each_set_bit(i, scan_mask, 8)
> - conf |= AD7192_CONF_CHAN(i);
> + conf |= FIELD_PREP(AD7192_CONF_CHAN_MASK, i);
>
> ret = ad_sd_write_reg(&st->sd, AD7192_REG_CONF, 3, conf);
> if (ret < 0)
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