Re: [PATCH v3 02/14] rtc: pcf2127: adapt for time/date registers at any offset

[Bruno Thomsen <bruno.thomsen@gmail.com>]

Den tor. 15. dec. 2022 kl. 16.20 skrev Hugo Villeneuve <hugo@hugovil.com>:
>
> From: Hugo Villeneuve <hvilleneuve@dimonoff.com>
>
> This will simplify the implementation of new variants into this driver.
>
> Some variants (PCF2131) have a 100th seconds register. This register is
> currently not supported in this driver.
>
> Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
> ---
>  drivers/rtc/rtc-pcf2127.c | 68 ++++++++++++++++++++++-----------------
>  1 file changed, 39 insertions(+), 29 deletions(-)
>
> diff --git a/drivers/rtc/rtc-pcf2127.c b/drivers/rtc/rtc-pcf2127.c
> index b9a5d47a439f..fb0caacaabee 100644
> --- a/drivers/rtc/rtc-pcf2127.c
> +++ b/drivers/rtc/rtc-pcf2127.c
> @@ -44,14 +44,17 @@
>  #define PCF2127_BIT_CTRL3_BF                   BIT(3)
>  #define PCF2127_BIT_CTRL3_BTSE                 BIT(4)
>  /* Time and date registers */
> -#define PCF2127_REG_SC                 0x03
> +#define PCF2127_REG_TIME_DATE_BASE     0x03
> +/* Time and date registers offsets (starting from base register) */
> +#define PCF2127_OFFSET_TD_SC           0
> +#define PCF2127_OFFSET_TD_MN           1
> +#define PCF2127_OFFSET_TD_HR           2
> +#define PCF2127_OFFSET_TD_DM           3
> +#define PCF2127_OFFSET_TD_DW           4
> +#define PCF2127_OFFSET_TD_MO           5
> +#define PCF2127_OFFSET_TD_YR           6
> +/* Time and date registers bits */
>  #define PCF2127_BIT_SC_OSF                     BIT(7)
> -#define PCF2127_REG_MN                 0x04
> -#define PCF2127_REG_HR                 0x05
> -#define PCF2127_REG_DM                 0x06
> -#define PCF2127_REG_DW                 0x07
> -#define PCF2127_REG_MO                 0x08
> -#define PCF2127_REG_YR                 0x09
>  /* Alarm registers */
>  #define PCF2127_REG_ALARM_SC           0x0A
>  #define PCF2127_REG_ALARM_MN           0x0B
> @@ -106,6 +109,7 @@ struct pcf21xx_config {
>         int max_register;
>         unsigned int has_nvmem:1;
>         unsigned int has_bit_wd_ctl_cd0:1;
> +       u8 regs_td_base; /* Time/data base registers. */

There is only one base register, so no need to add s.
I think td is an odd short, so maybe u8 reg_time_base.

/Bruno

>  };
>
>  struct pcf2127 {
> @@ -125,27 +129,31 @@ struct pcf2127 {
>  static int pcf2127_rtc_read_time(struct device *dev, struct rtc_time *tm)
>  {
>         struct pcf2127 *pcf2127 = dev_get_drvdata(dev);
> -       unsigned char buf[10];
> +       unsigned char buf[7];
> +       unsigned int ctrl3;
>         int ret;
>
>         /*
>          * Avoid reading CTRL2 register as it causes WD_VAL register
>          * value to reset to 0 which means watchdog is stopped.
>          */
> -       ret = regmap_bulk_read(pcf2127->regmap, PCF2127_REG_CTRL3,
> -                              (buf + PCF2127_REG_CTRL3),
> -                              ARRAY_SIZE(buf) - PCF2127_REG_CTRL3);
> -       if (ret) {
> -               dev_err(dev, "%s: read error\n", __func__);
> +       ret = regmap_read(pcf2127->regmap, PCF2127_REG_CTRL3, &ctrl3);
> +       if (ret)
>                 return ret;
> -       }
>
> -       if (buf[PCF2127_REG_CTRL3] & PCF2127_BIT_CTRL3_BLF)
> +       if (ctrl3 & PCF2127_BIT_CTRL3_BLF)
>                 dev_info(dev,
>                         "low voltage detected, check/replace RTC battery.\n");
>
> +       ret = regmap_bulk_read(pcf2127->regmap, pcf2127->cfg->regs_td_base,
> +                              buf, sizeof(buf));
> +       if (ret) {
> +               dev_err(dev, "%s: read error\n", __func__);
> +               return ret;
> +       }
> +
>         /* Clock integrity is not guaranteed when OSF flag is set. */
> -       if (buf[PCF2127_REG_SC] & PCF2127_BIT_SC_OSF) {
> +       if (buf[PCF2127_OFFSET_TD_SC] & PCF2127_BIT_SC_OSF) {
>                 /*
>                  * no need clear the flag here,
>                  * it will be cleared once the new date is saved
> @@ -158,18 +166,18 @@ static int pcf2127_rtc_read_time(struct device *dev, struct rtc_time *tm)
>         dev_dbg(dev,
>                 "%s: raw data is cr3=%02x, sec=%02x, min=%02x, hr=%02x, "
>                 "mday=%02x, wday=%02x, mon=%02x, year=%02x\n",
> -               __func__, buf[PCF2127_REG_CTRL3], buf[PCF2127_REG_SC],
> -               buf[PCF2127_REG_MN], buf[PCF2127_REG_HR],
> -               buf[PCF2127_REG_DM], buf[PCF2127_REG_DW],
> -               buf[PCF2127_REG_MO], buf[PCF2127_REG_YR]);
> -
> -       tm->tm_sec = bcd2bin(buf[PCF2127_REG_SC] & 0x7F);
> -       tm->tm_min = bcd2bin(buf[PCF2127_REG_MN] & 0x7F);
> -       tm->tm_hour = bcd2bin(buf[PCF2127_REG_HR] & 0x3F); /* rtc hr 0-23 */
> -       tm->tm_mday = bcd2bin(buf[PCF2127_REG_DM] & 0x3F);
> -       tm->tm_wday = buf[PCF2127_REG_DW] & 0x07;
> -       tm->tm_mon = bcd2bin(buf[PCF2127_REG_MO] & 0x1F) - 1; /* rtc mn 1-12 */
> -       tm->tm_year = bcd2bin(buf[PCF2127_REG_YR]);
> +               __func__, ctrl3, buf[PCF2127_OFFSET_TD_SC],
> +               buf[PCF2127_OFFSET_TD_MN], buf[PCF2127_OFFSET_TD_HR],
> +               buf[PCF2127_OFFSET_TD_DM], buf[PCF2127_OFFSET_TD_DW],
> +               buf[PCF2127_OFFSET_TD_MO], buf[PCF2127_OFFSET_TD_YR]);
> +
> +       tm->tm_sec = bcd2bin(buf[PCF2127_OFFSET_TD_SC] & 0x7F);
> +       tm->tm_min = bcd2bin(buf[PCF2127_OFFSET_TD_MN] & 0x7F);
> +       tm->tm_hour = bcd2bin(buf[PCF2127_OFFSET_TD_HR] & 0x3F); /* rtc hr 0-23 */
> +       tm->tm_mday = bcd2bin(buf[PCF2127_OFFSET_TD_DM] & 0x3F);
> +       tm->tm_wday = buf[PCF2127_OFFSET_TD_DW] & 0x07;
> +       tm->tm_mon = bcd2bin(buf[PCF2127_OFFSET_TD_MO] & 0x1F) - 1; /* rtc mn 1-12 */
> +       tm->tm_year = bcd2bin(buf[PCF2127_OFFSET_TD_YR]);
>         tm->tm_year += 100;
>
>         dev_dbg(dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
> @@ -207,7 +215,7 @@ static int pcf2127_rtc_set_time(struct device *dev, struct rtc_time *tm)
>         buf[i++] = bin2bcd(tm->tm_year - 100);
>
>         /* write register's data */
> -       err = regmap_bulk_write(pcf2127->regmap, PCF2127_REG_SC, buf, i);
> +       err = regmap_bulk_write(pcf2127->regmap, pcf2127->cfg->regs_td_base, buf, i);
>         if (err) {
>                 dev_err(dev,
>                         "%s: err=%d", __func__, err);
> @@ -650,11 +658,13 @@ static struct pcf21xx_config pcf21xx_cfg[] = {
>                 .max_register = 0x1d,
>                 .has_nvmem = 1,
>                 .has_bit_wd_ctl_cd0 = 1,
> +               .regs_td_base = PCF2127_REG_TIME_DATE_BASE,
>         },
>         [PCF2129] = {
>                 .max_register = 0x19,
>                 .has_nvmem = 0,
>                 .has_bit_wd_ctl_cd0 = 0,
> +               .regs_td_base = PCF2127_REG_TIME_DATE_BASE,
>         },
>  };
>
> --
> 2.30.2
>