Commit 23d8e4e8 authored by Tero Kristo's avatar Tero Kristo Committed by Luis Henriques

rtc: ds1307: Fix alarm programming for mcp794xx

commit 62c8c20a upstream.

mcp794xx alarm registers must be written in BCD format. However, the
alarm programming logic neglected this by adding one to the value
after bin2bcd conversion has been already done, writing bad values
to month register in case the alarm being set is in October. In this
case, the alarm month value becomes 0x0a instead of the expected 0x10.

Fix by moving the +1 addition within the bin2bcd call also.

Fixes: 1d1945d2 ("drivers/rtc/rtc-ds1307.c: add alarm support for mcp7941x chips")
Signed-off-by: default avatarTero Kristo <t-kristo@ti.com>
Acked-by: default avatarNishanth Menon <nm@ti.com>
Signed-off-by: default avatarAlexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: default avatarLuis Henriques <luis.henriques@canonical.com>
parent c444763e
...@@ -727,9 +727,9 @@ static int mcp7941x_set_alarm(struct device *dev, struct rtc_wkalrm *t) ...@@ -727,9 +727,9 @@ static int mcp7941x_set_alarm(struct device *dev, struct rtc_wkalrm *t)
regs[3] = bin2bcd(t->time.tm_sec); regs[3] = bin2bcd(t->time.tm_sec);
regs[4] = bin2bcd(t->time.tm_min); regs[4] = bin2bcd(t->time.tm_min);
regs[5] = bin2bcd(t->time.tm_hour); regs[5] = bin2bcd(t->time.tm_hour);
regs[6] = bin2bcd(t->time.tm_wday) + 1; regs[6] = bin2bcd(t->time.tm_wday + 1);
regs[7] = bin2bcd(t->time.tm_mday); regs[7] = bin2bcd(t->time.tm_mday);
regs[8] = bin2bcd(t->time.tm_mon) + 1; regs[8] = bin2bcd(t->time.tm_mon + 1);
/* Clear the alarm 0 interrupt flag. */ /* Clear the alarm 0 interrupt flag. */
regs[6] &= ~MCP7941X_BIT_ALMX_IF; regs[6] &= ~MCP7941X_BIT_ALMX_IF;
......
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