From: Uwe Kleine-König uwe@kleine-koenig.org
This patch has been added to the stable tree. If you have any objections, please let us know.
===============
[ Upstream commit f87e904ddd8f0ef120e46045b0addeb1cc88354e ]
There are several issues fixed in this patch:
- When alarm isn't enabled, set .enabled to zero instead of returning -EINVAL. - Ignore how IRQ1 is configured when determining if IRQ2 is on. - The three alarm registers have an enable flag which must be evaluated. - The chip always triggers when the seconds register gets 0.
Note that the rtc framework however doesn't handle the result correctly because it doesn't check wday being initialized and so interprets an alarm being set for 10:00 AM in three days as 10:00 AM tomorrow (or today if that's not over yet).
Signed-off-by: Uwe Kleine-König uwe@kleine-koenig.org Signed-off-by: Alexandre Belloni alexandre.belloni@free-electrons.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com --- drivers/rtc/rtc-s35390a.c | 40 +++++++++++++++++++++++++++++++--------- 1 file changed, 31 insertions(+), 9 deletions(-)
diff --git a/drivers/rtc/rtc-s35390a.c b/drivers/rtc/rtc-s35390a.c index f40afdd0e5f5..6507a01cf9ad 100644 --- a/drivers/rtc/rtc-s35390a.c +++ b/drivers/rtc/rtc-s35390a.c @@ -242,6 +242,8 @@ static int s35390a_set_alarm(struct i2c_client *client, struct rtc_wkalrm *alm)
if (alm->time.tm_wday != -1) buf[S35390A_ALRM_BYTE_WDAY] = bin2bcd(alm->time.tm_wday) | 0x80; + else + buf[S35390A_ALRM_BYTE_WDAY] = 0;
buf[S35390A_ALRM_BYTE_HOURS] = s35390a_hr2reg(s35390a, alm->time.tm_hour) | 0x80; @@ -269,23 +271,43 @@ static int s35390a_read_alarm(struct i2c_client *client, struct rtc_wkalrm *alm) if (err < 0) return err;
- if (bitrev8(sts) != S35390A_INT2_MODE_ALARM) - return -EINVAL; + if ((bitrev8(sts) & S35390A_INT2_MODE_MASK) != S35390A_INT2_MODE_ALARM) { + /* + * When the alarm isn't enabled, the register to configure + * the alarm time isn't accessible. + */ + alm->enabled = 0; + return 0; + } else { + alm->enabled = 1; + }
err = s35390a_get_reg(s35390a, S35390A_CMD_INT2_REG1, buf, sizeof(buf)); if (err < 0) return err;
/* This chip returns the bits of each byte in reverse order */ - for (i = 0; i < 3; ++i) { + for (i = 0; i < 3; ++i) buf[i] = bitrev8(buf[i]); - buf[i] &= ~0x80; - }
- alm->time.tm_wday = bcd2bin(buf[S35390A_ALRM_BYTE_WDAY]); - alm->time.tm_hour = s35390a_reg2hr(s35390a, - buf[S35390A_ALRM_BYTE_HOURS]); - alm->time.tm_min = bcd2bin(buf[S35390A_ALRM_BYTE_MINS]); + /* + * B0 of the three matching registers is an enable flag. Iff it is set + * the configured value is used for matching. + */ + if (buf[S35390A_ALRM_BYTE_WDAY] & 0x80) + alm->time.tm_wday = + bcd2bin(buf[S35390A_ALRM_BYTE_WDAY] & ~0x80); + + if (buf[S35390A_ALRM_BYTE_HOURS] & 0x80) + alm->time.tm_hour = + s35390a_reg2hr(s35390a, + buf[S35390A_ALRM_BYTE_HOURS] & ~0x80); + + if (buf[S35390A_ALRM_BYTE_MINS] & 0x80) + alm->time.tm_min = bcd2bin(buf[S35390A_ALRM_BYTE_MINS] & ~0x80); + + /* alarm triggers always at s=0 */ + alm->time.tm_sec = 0;
dev_dbg(&client->dev, "%s: alm is mins=%d, hours=%d, wday=%d\n", __func__, alm->time.tm_min, alm->time.tm_hour,