4 files changed, 40 insertions, 27 deletions

diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 5a538fc1cc85..53eb4e55b289 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -8,7 +8,7 @@ config RTC_LIB
 menuconfig RTC_CLASS
         bool "Real Time Clock"
         default n
-        depends on !S390
+        depends on !S390 && !UML
         select RTC_LIB
         help
           Generic RTC class support. If you say yes here, you will
diff --git a/drivers/rtc/class.c b/drivers/rtc/class.c
index 01a7df5317c1..e8326f26fa2f 100644
--- a/drivers/rtc/class.c
+++ b/drivers/rtc/class.c
@@ -21,16 +21,13 @@
 #include "rtc-core.h"
 
 
-static DEFINE_IDR(rtc_idr);
-static DEFINE_MUTEX(idr_lock);
+static DEFINE_IDA(rtc_ida);
 struct class *rtc_class;
 
 static void rtc_device_release(struct device *dev)
 {
         struct rtc_device *rtc = to_rtc_device(dev);
-        mutex_lock(&idr_lock);
-        idr_remove(&rtc_idr, rtc->id);
-        mutex_unlock(&idr_lock);
+        ida_simple_remove(&rtc_ida, rtc->id);
         kfree(rtc);
 }
 
@@ -146,25 +143,16 @@ struct rtc_device *rtc_device_register(const char *name, struct device *dev,
         struct rtc_wkalrm alrm;
         int id, err;
 
-        if (idr_pre_get(&rtc_idr, GFP_KERNEL) == 0) {
-                err = -ENOMEM;
+        id = ida_simple_get(&rtc_ida, 0, 0, GFP_KERNEL);
+        if (id < 0) {
+                err = id;
                 goto exit;
         }
 
-
-        mutex_lock(&idr_lock);
-        err = idr_get_new(&rtc_idr, NULL, &id);
-        mutex_unlock(&idr_lock);
-
-        if (err < 0)
-                goto exit;
-
-        id = id & MAX_ID_MASK;
-
         rtc = kzalloc(sizeof(struct rtc_device), GFP_KERNEL);
         if (rtc == NULL) {
                 err = -ENOMEM;
-                goto exit_idr;
+                goto exit_ida;
         }
 
         rtc->id = id;
@@ -222,10 +210,8 @@ struct rtc_device *rtc_device_register(const char *name, struct device *dev,
 exit_kfree:
         kfree(rtc);
 
-exit_idr:
-        mutex_lock(&idr_lock);
-        idr_remove(&rtc_idr, id);
-        mutex_unlock(&idr_lock);
+exit_ida:
+        ida_simple_remove(&rtc_ida, id);
 
 exit:
         dev_err(dev, "rtc core: unable to register %s, err = %d\n",
@@ -276,7 +262,7 @@ static void __exit rtc_exit(void)
 {
         rtc_dev_exit();
         class_destroy(rtc_class);
-        idr_destroy(&rtc_idr);
+        ida_destroy(&rtc_ida);
 }
 
 subsys_initcall(rtc_init);
diff --git a/drivers/rtc/rtc-ds1307.c b/drivers/rtc/rtc-ds1307.c
index b2005b44e4f7..62b0763b7b9a 100644
--- a/drivers/rtc/rtc-ds1307.c
+++ b/drivers/rtc/rtc-ds1307.c
@@ -34,6 +34,7 @@ enum ds_type {
         ds_1388,
         ds_3231,
         m41t00,
+        mcp7941x,
         rx_8025,
         // rs5c372 too?  different address...
 };
@@ -43,6 +44,7 @@ enum ds_type {
 #define DS1307_REG_SECS         0x00    /* 00-59 */
 #       define DS1307_BIT_CH            0x80
 #       define DS1340_BIT_nEOSC         0x80
+#       define MCP7941X_BIT_ST          0x80
 #define DS1307_REG_MIN          0x01    /* 00-59 */
 #define DS1307_REG_HOUR         0x02    /* 00-23, or 1-12{am,pm} */
 #       define DS1307_BIT_12HR          0x40    /* in REG_HOUR */
@@ -50,6 +52,7 @@ enum ds_type {
 #       define DS1340_BIT_CENTURY_EN    0x80    /* in REG_HOUR */
 #       define DS1340_BIT_CENTURY       0x40    /* in REG_HOUR */
 #define DS1307_REG_WDAY         0x03    /* 01-07 */
+#       define MCP7941X_BIT_VBATEN      0x08
 #define DS1307_REG_MDAY         0x04    /* 01-31 */
 #define DS1307_REG_MONTH        0x05    /* 01-12 */
 #       define DS1337_BIT_CENTURY       0x80    /* in REG_MONTH */
@@ -137,6 +140,8 @@ static const struct chip_desc chips[] = {
 },
 [m41t00] = {
 },
+[mcp7941x] = {
+},
 [rx_8025] = {
 }, };
 
@@ -149,6 +154,7 @@ static const struct i2c_device_id ds1307_id[] = {
         { "ds1340", ds_1340 },
         { "ds3231", ds_3231 },
         { "m41t00", m41t00 },
+        { "mcp7941x", mcp7941x },
         { "pt7c4338", ds_1307 },
         { "rx8025", rx_8025 },
         { }
@@ -365,6 +371,10 @@ static int ds1307_set_time(struct device *dev, struct rtc_time *t)
                 buf[DS1307_REG_HOUR] |= DS1340_BIT_CENTURY_EN
                                 | DS1340_BIT_CENTURY;
                 break;
+        case mcp7941x:
+                buf[DS1307_REG_SECS] |= MCP7941X_BIT_ST;
+                buf[DS1307_REG_WDAY] |= MCP7941X_BIT_VBATEN;
+                break;
         default:
                 break;
         }
@@ -809,6 +819,23 @@ read_rtc:
                         dev_warn(&client->dev, "SET TIME!\n");
                 }
                 break;
+        case mcp7941x:
+                /* make sure that the backup battery is enabled */
+                if (!(ds1307->regs[DS1307_REG_WDAY] & MCP7941X_BIT_VBATEN)) {
+                        i2c_smbus_write_byte_data(client, DS1307_REG_WDAY,
+                                        ds1307->regs[DS1307_REG_WDAY]
+                                        | MCP7941X_BIT_VBATEN);
+                }
+
+                /* clock halted?  turn it on, so clock can tick. */
+                if (!(tmp & MCP7941X_BIT_ST)) {
+                        i2c_smbus_write_byte_data(client, DS1307_REG_SECS,
+                                        MCP7941X_BIT_ST);
+                        dev_warn(&client->dev, "SET TIME!\n");
+                        goto read_rtc;
+                }
+
+                break;
         case rx_8025:
         case ds_1337:
         case ds_1339:
diff --git a/drivers/rtc/rtc-mc13xxx.c b/drivers/rtc/rtc-mc13xxx.c
index a1a278bc340d..9d0c3b478d55 100644
--- a/drivers/rtc/rtc-mc13xxx.c
+++ b/drivers/rtc/rtc-mc13xxx.c
@@ -309,7 +309,7 @@ static irqreturn_t mc13xxx_rtc_reset_handler(int irq, void *dev)
         return IRQ_HANDLED;
 }
 
-static int __devinit mc13xxx_rtc_probe(struct platform_device *pdev)
+static int __init mc13xxx_rtc_probe(struct platform_device *pdev)
 {
         int ret;
         struct mc13xxx_rtc *priv;
@@ -378,7 +378,7 @@ err_reset_irq_request:
         return ret;
 }
 
-static int __devexit mc13xxx_rtc_remove(struct platform_device *pdev)
+static int __exit mc13xxx_rtc_remove(struct platform_device *pdev)
 {
         struct mc13xxx_rtc *priv = platform_get_drvdata(pdev);
 
@@ -410,7 +410,7 @@ const struct platform_device_id mc13xxx_rtc_idtable[] = {
 
 static struct platform_driver mc13xxx_rtc_driver = {
         .id_table = mc13xxx_rtc_idtable,
-        .remove = __devexit_p(mc13xxx_rtc_remove),
+        .remove = __exit_p(mc13xxx_rtc_remove),
         .driver = {
                 .name = DRIVER_NAME,
                 .owner = THIS_MODULE,