Hello,
On 23/11/2020 11:38:44+0100, Daniel González Cabanelas wrote:
> The Ricoh R2221x, R2223x, RS5C372, RV5C387A chips can handle 1 week
> alarms.
>
> Read the "wday" alarm register and convert it to a date to support up 1
> week in our driver.
>
> Signed-off-by: Daniel González Cabanelas <dgcbueu@xxxxxxxxx>
> ---
> drivers/rtc/rtc-rs5c372.c | 48 ++++++++++++++++++++++++++++++++++-----
> 1 file changed, 42 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/rtc/rtc-rs5c372.c b/drivers/rtc/rtc-rs5c372.c
> index 3bd6eaa0d..94b778c6e 100644
> --- a/drivers/rtc/rtc-rs5c372.c
> +++ b/drivers/rtc/rtc-rs5c372.c
> @@ -393,7 +393,9 @@ static int rs5c_read_alarm(struct device *dev, struct rtc_wkalrm *t)
> {
> struct i2c_client *client = to_i2c_client(dev);
> struct rs5c372 *rs5c = i2c_get_clientdata(client);
> - int status;
> + int status, wday_offs;
> + struct rtc_time rtc;
You have a few spaces before tabs, please fix them.
> + unsigned long alarm_secs;
>
> status = rs5c_get_regs(rs5c);
> if (status < 0)
> @@ -403,6 +405,30 @@ static int rs5c_read_alarm(struct device *dev, struct rtc_wkalrm *t)
> t->time.tm_sec = 0;
> t->time.tm_min = bcd2bin(rs5c->regs[RS5C_REG_ALARM_A_MIN] & 0x7f);
> t->time.tm_hour = rs5c_reg2hr(rs5c, rs5c->regs[RS5C_REG_ALARM_A_HOURS]);
> + t->time.tm_wday = ffs(rs5c->regs[RS5C_REG_ALARM_A_WDAY] & 0x7f) - 1;
> +
> + /* determine the day, month and year based on alarm wday, taking as a
> + * reference the current time from the rtc
> + */
> + status = rs5c372_rtc_read_time(dev, &rtc);
> + if (status < 0)
> + return status;
> +
> + wday_offs = t->time.tm_wday - rtc.tm_wday;
Note that you can not rely on tm_wday being set correctly. The core will
not (currently) enforce that and most tools jut pass a bogus value or 0.
So you need to calculate wday in rs5c372_rtc_set_time.
I'm currently working on a way for the drivers to ask the core to ensure
wday is correct.
> + alarm_secs = mktime64(rtc.tm_year + 1900,
> + rtc.tm_mon + 1,
> + rtc.tm_mday + wday_offs,
> + t->time.tm_hour,
> + t->time.tm_min,
> + t->time.tm_sec);
> +
> + if (wday_offs < 0 || (wday_offs == 0 &&
> + (t->time.tm_hour < rtc.tm_hour ||
> + (t->time.tm_hour == rtc.tm_hour &&
> + t->time.tm_min <= rtc.tm_min))))
> + alarm_secs += 7 * 86400;
> +
> + rtc_time64_to_tm(alarm_secs, &t->time);
>
> /* ... and status */
> t->enabled = !!(rs5c->regs[RS5C_REG_CTRL1] & RS5C_CTRL1_AALE);
> @@ -417,12 +443,20 @@ static int rs5c_set_alarm(struct device *dev, struct rtc_wkalrm *t)
> struct rs5c372 *rs5c = i2c_get_clientdata(client);
> int status, addr, i;
> unsigned char buf[3];
> + struct rtc_time rtc_tm;
> + unsigned long rtc_secs, alarm_secs;
>
> - /* only handle up to 24 hours in the future, like RTC_ALM_SET */
> - if (t->time.tm_mday != -1
> - || t->time.tm_mon != -1
> - || t->time.tm_year != -1)
> + /* chip only can handle alarms up to one week in the future*/
> + status = rs5c372_rtc_read_time(dev, &rtc_tm);
> + if (status)
> + return status;
> + rtc_secs = rtc_tm_to_time64(&rtc_tm);
> + alarm_secs = rtc_tm_to_time64(&t->time);
> + if (alarm_secs >= rtc_secs + 7 * 86400) {
> + dev_err(dev, "%s: alarm maximum is one week in the future (%d)\n",
> + __func__, status);
Please avoid adding an error message. It will not be read anyway.
> return -EINVAL;
Maybe it is a good opportunity to change to -ERANGE?
> + }
>
> /* REVISIT: round up tm_sec */
>
> @@ -443,7 +477,9 @@ static int rs5c_set_alarm(struct device *dev, struct rtc_wkalrm *t)
> /* set alarm */
> buf[0] = bin2bcd(t->time.tm_min);
> buf[1] = rs5c_hr2reg(rs5c, t->time.tm_hour);
> - buf[2] = 0x7f; /* any/all days */
> + /* each bit is the day of the week, 0x7f means all days */
> + buf[2] = (t->time.tm_wday >= 0 && t->time.tm_wday < 7) ?
> + BIT(t->time.tm_wday) : 0x7f;
Here, you also need to calculate buf[2] from t->time.tm_mday instead of
relying on t->time.tm_wday.
--
Alexandre Belloni, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com
