1 files changed, 49 insertions, 5 deletions

diff --git a/drivers/rtc/rtc-max8998.c b/drivers/rtc/rtc-max8998.c
index f22dee35f330..3f7bc6b9fefa 100644
--- a/drivers/rtc/rtc-max8998.c
+++ b/drivers/rtc/rtc-max8998.c
@@ -20,6 +20,7 @@
 #include <linux/platform_device.h>
 #include <linux/mfd/max8998.h>
 #include <linux/mfd/max8998-private.h>
+#include <linux/delay.h>
 
 #define MAX8998_RTC_SEC                 0x00
 #define MAX8998_RTC_MIN                 0x01
@@ -73,6 +74,7 @@ struct max8998_rtc_info {
         struct i2c_client       *rtc;
         struct rtc_device       *rtc_dev;
         int irq;
+        bool lp3974_bug_workaround;
 };
 
 static void max8998_data_to_tm(u8 *data, struct rtc_time *tm)
@@ -124,10 +126,16 @@ static int max8998_rtc_set_time(struct device *dev, struct rtc_time *tm)
 {
         struct max8998_rtc_info *info = dev_get_drvdata(dev);
         u8 data[8];
+        int ret;
 
         max8998_tm_to_data(tm, data);
 
-        return max8998_bulk_write(info->rtc, MAX8998_RTC_SEC, 8, data);
+        ret = max8998_bulk_write(info->rtc, MAX8998_RTC_SEC, 8, data);
+
+        if (info->lp3974_bug_workaround)
+                msleep(2000);
+
+        return ret;
 }
 
 static int max8998_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
@@ -163,12 +171,29 @@ static int max8998_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 
 static int max8998_rtc_stop_alarm(struct max8998_rtc_info *info)
 {
-        return max8998_write_reg(info->rtc, MAX8998_ALARM0_CONF, 0);
+        int ret = max8998_write_reg(info->rtc, MAX8998_ALARM0_CONF, 0);
+
+        if (info->lp3974_bug_workaround)
+                msleep(2000);
+
+        return ret;
 }
 
 static int max8998_rtc_start_alarm(struct max8998_rtc_info *info)
 {
-        return max8998_write_reg(info->rtc, MAX8998_ALARM0_CONF, 0x77);
+        int ret;
+        u8 alarm0_conf = 0x77;
+
+        /* LP3974 with delay bug chips has rtc alarm bugs with "MONTH" field */
+        if (info->lp3974_bug_workaround)
+                alarm0_conf = 0x57;
+
+        ret = max8998_write_reg(info->rtc, MAX8998_ALARM0_CONF, alarm0_conf);
+
+        if (info->lp3974_bug_workaround)
+                msleep(2000);
+
+        return ret;
 }
 
 static int max8998_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
@@ -187,10 +212,13 @@ static int max8998_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
         if (ret < 0)
                 return ret;
 
+        if (info->lp3974_bug_workaround)
+                msleep(2000);
+
         if (alrm->enabled)
-                return max8998_rtc_start_alarm(info);
+                ret = max8998_rtc_start_alarm(info);
 
-        return 0;
+        return ret;
 }
 
 static int max8998_rtc_alarm_irq_enable(struct device *dev,
@@ -224,6 +252,7 @@ static const struct rtc_class_ops max8998_rtc_ops = {
 static int __devinit max8998_rtc_probe(struct platform_device *pdev)
 {
         struct max8998_dev *max8998 = dev_get_drvdata(pdev->dev.parent);
+        struct max8998_platform_data *pdata = dev_get_platdata(max8998->dev);
         struct max8998_rtc_info *info;
         int ret;
 
@@ -249,10 +278,18 @@ static int __devinit max8998_rtc_probe(struct platform_device *pdev)
 
         ret = request_threaded_irq(info->irq, NULL, max8998_rtc_alarm_irq, 0,
                         "rtc-alarm0", info);
+
         if (ret < 0)
                 dev_err(&pdev->dev, "Failed to request alarm IRQ: %d: %d\n",
                         info->irq, ret);
 
+        dev_info(&pdev->dev, "RTC CHIP NAME: %s\n", pdev->id_entry->name);
+        if (pdata->rtc_delay) {
+                info->lp3974_bug_workaround = true;
+                dev_warn(&pdev->dev, "LP3974 with RTC REGERR option."
+                                " RTC updates will be extremely slow.\n");
+        }
+
         return 0;
 
 out_rtc:
@@ -273,6 +310,12 @@ static int __devexit max8998_rtc_remove(struct platform_device *pdev)
         return 0;
 }
 
+static const struct platform_device_id max8998_rtc_id[] = {
+        { "max8998-rtc", TYPE_MAX8998 },
+        { "lp3974-rtc", TYPE_LP3974 },
+        { }
+};
+
 static struct platform_driver max8998_rtc_driver = {
         .driver         = {
                 .name   = "max8998-rtc",
@@ -280,6 +323,7 @@ static struct platform_driver max8998_rtc_driver = {
         },
         .probe          = max8998_rtc_probe,
         .remove         = __devexit_p(max8998_rtc_remove),
+        .id_table       = max8998_rtc_id,
 };
 
 static int __init max8998_rtc_init(void)