Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-serial

[pandora-kernel.git] / drivers / rtc / rtc-ds1672.c

diff --git a/drivers/rtc/rtc-ds1672.c b/drivers/rtc/rtc-ds1672.c
index 358695a..9c68ec9 100644 (file)
--- a/drivers/rtc/rtc-ds1672.c
+++ b/drivers/rtc/rtc-ds1672.c
@@ -1,6 +1,8 @@
 /*
  * An rtc/i2c driver for the Dallas DS1672
- * Copyright 2005 Alessandro Zummo
+ * Copyright 2005-06 Tower Technologies
+ *
+ * Author: Alessandro Zummo <a.zummo@towertech.it>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
@@ -11,7 +13,7 @@
 #include <linux/i2c.h>
 #include <linux/rtc.h>
 
-#define DRV_VERSION "0.2"
+#define DRV_VERSION "0.3"
 
 /* Addresses to scan: none. This chip cannot be detected. */
 static unsigned short normal_i2c[] = { I2C_CLIENT_END };
@@ -25,6 +27,7 @@ I2C_CLIENT_INSMOD;
 #define DS1672_REG_CONTROL     4
 #define DS1672_REG_TRICKLE     5
 
+#define DS1672_REG_CONTROL_EOSC        0x80
 
 /* Prototypes */
 static int ds1672_probe(struct i2c_adapter *adapter, int address, int kind);
@@ -53,8 +56,7 @@ static int ds1672_get_datetime(struct i2c_client *client, struct rtc_time *tm)
 
        dev_dbg(&client->dev,
                "%s: raw read data - counters=%02x,%02x,%02x,%02x\n"
-               __FUNCTION__,
-               buf[0], buf[1], buf[2], buf[3]);
+               __FUNCTION__, buf[0], buf[1], buf[2], buf[3]);
 
        time = (buf[3] << 24) | (buf[2] << 16) | (buf[1] << 8) | buf[0];
 
@@ -62,8 +64,7 @@ static int ds1672_get_datetime(struct i2c_client *client, struct rtc_time *tm)
 
        dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
                "mday=%d, mon=%d, year=%d, wday=%d\n",
-               __FUNCTION__,
-               tm->tm_sec, tm->tm_min, tm->tm_hour,
+               __FUNCTION__, tm->tm_sec, tm->tm_min, tm->tm_hour,
                tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
 
        return 0;
@@ -72,16 +73,17 @@ static int ds1672_get_datetime(struct i2c_client *client, struct rtc_time *tm)
 static int ds1672_set_mmss(struct i2c_client *client, unsigned long secs)
 {
        int xfer;
-       unsigned char buf[5];
+       unsigned char buf[6];
 
        buf[0] = DS1672_REG_CNT_BASE;
        buf[1] = secs & 0x000000FF;
        buf[2] = (secs & 0x0000FF00) >> 8;
        buf[3] = (secs & 0x00FF0000) >> 16;
        buf[4] = (secs & 0xFF000000) >> 24;
+       buf[5] = 0;     /* set control reg to enable counting */
 
-       xfer = i2c_master_send(client, buf, 5);
-       if (xfer != 5) {
+       xfer = i2c_master_send(client, buf, 6);
+       if (xfer != 6) {
                dev_err(&client->dev, "%s: send: %d\n", __FUNCTION__, xfer);
                return -EIO;
        }
@@ -120,7 +122,41 @@ static int ds1672_rtc_set_mmss(struct device *dev, unsigned long secs)
        return ds1672_set_mmss(to_i2c_client(dev), secs);
 }
 
-static struct rtc_class_ops ds1672_rtc_ops = {
+static int ds1672_get_control(struct i2c_client *client, u8 *status)
+{
+       unsigned char addr = DS1672_REG_CONTROL;
+
+       struct i2c_msg msgs[] = {
+               { client->addr, 0, 1, &addr },          /* setup read ptr */
+               { client->addr, I2C_M_RD, 1, status },  /* read control */
+       };
+
+       /* read control register */
+       if ((i2c_transfer(client->adapter, &msgs[0], 2)) != 2) {
+               dev_err(&client->dev, "%s: read error\n", __FUNCTION__);
+               return -EIO;
+       }
+
+       return 0;
+}
+
+/* following are the sysfs callback functions */
+static ssize_t show_control(struct device *dev, struct device_attribute *attr, char *buf)
+{
+       struct i2c_client *client = to_i2c_client(dev);
+       u8 control;
+       int err;
+
+       err = ds1672_get_control(client, &control);
+       if (err)
+               return err;
+
+       return sprintf(buf, "%s\n", (control & DS1672_REG_CONTROL_EOSC)
+                                       ? "disabled" : "enabled");
+}
+static DEVICE_ATTR(control, S_IRUGO, show_control, NULL);
+
+static const struct rtc_class_ops ds1672_rtc_ops = {
        .read_time      = ds1672_rtc_read_time,
        .set_time       = ds1672_rtc_set_time,
        .set_mmss       = ds1672_rtc_set_mmss,
@@ -128,7 +164,6 @@ static struct rtc_class_ops ds1672_rtc_ops = {
 
 static int ds1672_attach(struct i2c_adapter *adapter)
 {
-       dev_dbg(&adapter->dev, "%s\n", __FUNCTION__);
        return i2c_probe(adapter, &addr_data, ds1672_probe);
 }
 
@@ -137,8 +172,6 @@ static int ds1672_detach(struct i2c_client *client)
        int err;
        struct rtc_device *rtc = i2c_get_clientdata(client);
 
-       dev_dbg(&client->dev, "%s\n", __FUNCTION__);
-
        if (rtc)
                rtc_device_unregister(rtc);
 
@@ -162,6 +195,7 @@ static struct i2c_driver ds1672_driver = {
 static int ds1672_probe(struct i2c_adapter *adapter, int address, int kind)
 {
        int err = 0;
+       u8 control;
        struct i2c_client *client;
        struct rtc_device *rtc;
 
@@ -195,13 +229,23 @@ static int ds1672_probe(struct i2c_adapter *adapter, int address, int kind)
 
        if (IS_ERR(rtc)) {
                err = PTR_ERR(rtc);
-               dev_err(&client->dev,
-                       "unable to register the class device\n");
                goto exit_detach;
        }
 
        i2c_set_clientdata(client, rtc);
 
+       /* read control register */
+       err = ds1672_get_control(client, &control);
+       if (err)
+               goto exit_detach;
+
+       if (control & DS1672_REG_CONTROL_EOSC)
+               dev_warn(&client->dev, "Oscillator not enabled. "
+                                       "Set time to enable.\n");
+
+       /* Register sysfs hooks */
+       device_create_file(&client->dev, &dev_attr_control);
+
        return 0;
 
 exit_detach: