rtc: rtc-ds1307 add ds3231
Add ds3231 variant. For that, the BBSQI bit position was changed from a
simple define into a lookup-array as it differs. This also removes
writing to an unused bit in case of the ds1337.
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/rtc/rtc-ds1307.c b/drivers/rtc/rtc-ds1307.c
index 52e2427..8a6f9a9 100644
--- a/drivers/rtc/rtc-ds1307.c
+++ b/drivers/rtc/rtc-ds1307.c
@@ -32,6 +32,7 @@
ds_1339,
ds_1340,
ds_1388,
+ ds_3231,
m41t00,
rx_8025,
// rs5c372 too? different address...
@@ -67,6 +68,7 @@
#define DS1337_REG_CONTROL 0x0e
# define DS1337_BIT_nEOSC 0x80
# define DS1339_BIT_BBSQI 0x20
+# define DS3231_BIT_BBSQW 0x40 /* same as BBSQI */
# define DS1337_BIT_RS2 0x10
# define DS1337_BIT_RS1 0x08
# define DS1337_BIT_INTCN 0x04
@@ -130,6 +132,9 @@
},
[ds_1340] = {
},
+[ds_3231] = {
+ .alarm = 1,
+},
[m41t00] = {
},
[rx_8025] = {
@@ -142,6 +147,7 @@
{ "ds1339", ds_1339 },
{ "ds1388", ds_1388 },
{ "ds1340", ds_1340 },
+ { "ds3231", ds_3231 },
{ "m41t00", m41t00 },
{ "rx8025", rx_8025 },
{ }
@@ -356,6 +362,7 @@
switch (ds1307->type) {
case ds_1337:
case ds_1339:
+ case ds_3231:
buf[DS1307_REG_MONTH] |= DS1337_BIT_CENTURY;
break;
case ds_1340:
@@ -628,6 +635,11 @@
struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
int want_irq = false;
unsigned char *buf;
+ static const int bbsqi_bitpos[] = {
+ [ds_1337] = 0,
+ [ds_1339] = DS1339_BIT_BBSQI,
+ [ds_3231] = DS3231_BIT_BBSQW,
+ };
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)
&& !i2c_check_functionality(adapter, I2C_FUNC_SMBUS_I2C_BLOCK))
@@ -654,6 +666,7 @@
switch (ds1307->type) {
case ds_1337:
case ds_1339:
+ case ds_3231:
/* has IRQ? */
if (ds1307->client->irq > 0 && chip->alarm) {
INIT_WORK(&ds1307->work, ds1307_work);
@@ -673,12 +686,12 @@
ds1307->regs[0] &= ~DS1337_BIT_nEOSC;
/* Using IRQ? Disable the square wave and both alarms.
- * For ds1339, be sure alarms can trigger when we're
- * running on Vbackup (BBSQI); we assume ds1337 will
- * ignore that bit
+ * For some variants, be sure alarms can trigger when we're
+ * running on Vbackup (BBSQI/BBSQW)
*/
if (want_irq) {
- ds1307->regs[0] |= DS1337_BIT_INTCN | DS1339_BIT_BBSQI;
+ ds1307->regs[0] |= DS1337_BIT_INTCN
+ | bbsqi_bitpos[ds1307->type];
ds1307->regs[0] &= ~(DS1337_BIT_A2IE | DS1337_BIT_A1IE);
}
@@ -825,6 +838,7 @@
case ds_1337:
case ds_1339:
case ds_1388:
+ case ds_3231:
break;
}