rtc: ds1307: store previous charge default per chip

[sfrench/cifs-2.6.git] / drivers / rtc / rtc-ds1307.c

diff --git a/drivers/rtc/rtc-ds1307.c b/drivers/rtc/rtc-ds1307.c
index 64fa1318817c8a43cec008b4161d7a92c16bac2f..fdd6f9fda6f9fabcb03190acf587762220650c3e 100644 (file)
--- a/drivers/rtc/rtc-ds1307.c
+++ b/drivers/rtc/rtc-ds1307.c
@@ -195,6 +195,11 @@ struct chip_desc {
         * the resistor between Vcc and Vbackup?
         */
        bool                    requires_trickle_resistor;
+       /* Some RTC's batteries and supercaps were charged by default, others
+        * allow charging but were not configured previously to do so.
+        * Remember this behavior to stay backwards compatible.
+        */
+       bool                    charge_default;
 };
 
 static const struct chip_desc chips[last_ds_type];
@@ -991,6 +996,7 @@ static const struct chip_desc chips[last_ds_type] = {
                .trickle_charger_reg = 0x10,
                .do_trickle_setup = &do_trickle_setup_ds1339,
                .requires_trickle_resistor = true,
+               .charge_default = true,
        },
        [ds_1340] = {
                .century_reg    = DS1307_REG_HOUR,
@@ -999,6 +1005,7 @@ static const struct chip_desc chips[last_ds_type] = {
                .do_trickle_setup = &do_trickle_setup_ds1339,
                .trickle_charger_reg = 0x08,
                .requires_trickle_resistor = true,
+               .charge_default = true,
        },
        [ds_1341] = {
                .century_reg    = DS1307_REG_MONTH,
@@ -1307,7 +1314,7 @@ static u8 ds1307_trickle_init(struct ds1307 *ds1307,
                              const struct chip_desc *chip)
 {
        u32 ohms;
-       bool diode = true;
+       bool diode = chip->charge_default;
 
        if (!chip->do_trickle_setup)
                return 0;