Re: [PATCH v2 03/22] rtc: pm8xxx: use regmap_update_bits()

From: David Collins
Date: Mon Feb 06 2023 - 22:14:53 EST


On 2/2/23 07:54, Johan Hovold wrote:
> Switch to using regmap_update_bits() instead of open coding
> read-modify-write accesses.
>
> Signed-off-by: Johan Hovold <johan+linaro@xxxxxxxxxx>
> ---
> drivers/rtc/rtc-pm8xxx.c | 87 ++++++++++------------------------------
> 1 file changed, 22 insertions(+), 65 deletions(-)

Reviewed-by: David Collins <quic_collinsd@xxxxxxxxxxx>


> diff --git a/drivers/rtc/rtc-pm8xxx.c b/drivers/rtc/rtc-pm8xxx.c
> index f49bda999e02..8c2847ac64f4 100644
> --- a/drivers/rtc/rtc-pm8xxx.c
> +++ b/drivers/rtc/rtc-pm8xxx.c
> @@ -78,10 +78,10 @@ static int pm8xxx_rtc_set_time(struct device *dev, struct rtc_time *tm)
> {
> int rc, i;
> unsigned long secs, irq_flags;
> - u8 value[NUM_8_BIT_RTC_REGS], alarm_enabled = 0, rtc_disabled = 0;
> - unsigned int ctrl_reg, rtc_ctrl_reg;
> struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
> const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
> + u8 value[NUM_8_BIT_RTC_REGS];
> + bool alarm_enabled;
>
> if (!rtc_dd->allow_set_time)
> return -ENODEV;
> @@ -97,31 +97,16 @@ static int pm8xxx_rtc_set_time(struct device *dev, struct rtc_time *tm)
>
> spin_lock_irqsave(&rtc_dd->ctrl_reg_lock, irq_flags);
>
> - rc = regmap_read(rtc_dd->regmap, regs->alarm_ctrl, &ctrl_reg);
> + rc = regmap_update_bits_check(rtc_dd->regmap, regs->alarm_ctrl,
> + regs->alarm_en, 0, &alarm_enabled);
> if (rc)
> goto rtc_rw_fail;
>
> - if (ctrl_reg & regs->alarm_en) {
> - alarm_enabled = 1;
> - ctrl_reg &= ~regs->alarm_en;
> - rc = regmap_write(rtc_dd->regmap, regs->alarm_ctrl, ctrl_reg);
> - if (rc)
> - goto rtc_rw_fail;
> - }
> -

I like this usage of regmap_update_bits_check(). It is a great helper
to use in this situation. It really helps to simplify the logic.

Take care,
David