rtc-pcf8563: add chip id
[pandora-kernel.git] / drivers / rtc / rtc-pcf8563.c
index 4b72b8e..748a502 100644 (file)
 #include <linux/bcd.h>
 #include <linux/rtc.h>
 
-#define DRV_VERSION "0.4.2"
-
-/* Addresses to scan: none
- * This chip cannot be reliably autodetected. An empty eeprom
- * located at 0x51 will pass the validation routine due to
- * the way the registers are implemented.
- */
-static unsigned short normal_i2c[] = { I2C_CLIENT_END };
-
-/* Module parameters */
-I2C_CLIENT_INSMOD;
+#define DRV_VERSION "0.4.3"
 
 #define PCF8563_REG_ST1                0x00 /* status */
 #define PCF8563_REG_ST2                0x01
@@ -53,8 +43,26 @@ I2C_CLIENT_INSMOD;
 #define PCF8563_SC_LV          0x80 /* low voltage */
 #define PCF8563_MO_C           0x80 /* century */
 
-static int pcf8563_probe(struct i2c_adapter *adapter, int address, int kind);
-static int pcf8563_detach(struct i2c_client *client);
+static struct i2c_driver pcf8563_driver;
+
+struct pcf8563 {
+       struct rtc_device *rtc;
+       /*
+        * The meaning of MO_C bit varies by the chip type.
+        * From PCF8563 datasheet: this bit is toggled when the years
+        * register overflows from 99 to 00
+        *   0 indicates the century is 20xx
+        *   1 indicates the century is 19xx
+        * From RTC8564 datasheet: this bit indicates change of
+        * century. When the year digit data overflows from 99 to 00,
+        * this bit is set. By presetting it to 0 while still in the
+        * 20th century, it will be set in year 2000, ...
+        * There seems no reliable way to know how the system use this
+        * bit.  So let's do it heuristically, assuming we are live in
+        * 1970...2069.
+        */
+       int c_polarity; /* 0: MO_C=1 means 19xx, otherwise MO_C=1 means 20xx */
+};
 
 /*
  * In the routines that deal directly with the pcf8563 hardware, we use
@@ -62,6 +70,7 @@ static int pcf8563_detach(struct i2c_client *client);
  */
 static int pcf8563_get_datetime(struct i2c_client *client, struct rtc_time *tm)
 {
+       struct pcf8563 *pcf8563 = i2c_get_clientdata(client);
        unsigned char buf[13] = { PCF8563_REG_ST1 };
 
        struct i2c_msg msgs[] = {
@@ -71,7 +80,7 @@ static int pcf8563_get_datetime(struct i2c_client *client, struct rtc_time *tm)
 
        /* read registers */
        if ((i2c_transfer(client->adapter, msgs, 2)) != 2) {
-               dev_err(&client->dev, "%s: read error\n", __FUNCTION__);
+               dev_err(&client->dev, "%s: read error\n", __func__);
                return -EIO;
        }
 
@@ -82,7 +91,7 @@ static int pcf8563_get_datetime(struct i2c_client *client, struct rtc_time *tm)
        dev_dbg(&client->dev,
                "%s: raw data is st1=%02x, st2=%02x, sec=%02x, min=%02x, hr=%02x, "
                "mday=%02x, wday=%02x, mon=%02x, year=%02x\n",
-               __FUNCTION__,
+               __func__,
                buf[0], buf[1], buf[2], buf[3],
                buf[4], buf[5], buf[6], buf[7],
                buf[8]);
@@ -94,12 +103,16 @@ static int pcf8563_get_datetime(struct i2c_client *client, struct rtc_time *tm)
        tm->tm_mday = BCD2BIN(buf[PCF8563_REG_DM] & 0x3F);
        tm->tm_wday = buf[PCF8563_REG_DW] & 0x07;
        tm->tm_mon = BCD2BIN(buf[PCF8563_REG_MO] & 0x1F) - 1; /* rtc mn 1-12 */
-       tm->tm_year = BCD2BIN(buf[PCF8563_REG_YR])
-               + (buf[PCF8563_REG_MO] & PCF8563_MO_C ? 0 : 100);
+       tm->tm_year = BCD2BIN(buf[PCF8563_REG_YR]);
+       if (tm->tm_year < 70)
+               tm->tm_year += 100;     /* assume we are in 1970...2069 */
+       /* detect the polarity heuristically. see note above. */
+       pcf8563->c_polarity = (buf[PCF8563_REG_MO] & PCF8563_MO_C) ?
+               (tm->tm_year >= 100) : (tm->tm_year < 100);
 
        dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
                "mday=%d, mon=%d, year=%d, wday=%d\n",
-               __FUNCTION__,
+               __func__,
                tm->tm_sec, tm->tm_min, tm->tm_hour,
                tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
 
@@ -114,12 +127,13 @@ static int pcf8563_get_datetime(struct i2c_client *client, struct rtc_time *tm)
 
 static int pcf8563_set_datetime(struct i2c_client *client, struct rtc_time *tm)
 {
+       struct pcf8563 *pcf8563 = i2c_get_clientdata(client);
        int i, err;
        unsigned char buf[9];
 
        dev_dbg(&client->dev, "%s: secs=%d, mins=%d, hours=%d, "
                "mday=%d, mon=%d, year=%d, wday=%d\n",
-               __FUNCTION__,
+               __func__,
                tm->tm_sec, tm->tm_min, tm->tm_hour,
                tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
 
@@ -135,7 +149,7 @@ static int pcf8563_set_datetime(struct i2c_client *client, struct rtc_time *tm)
 
        /* year and century */
        buf[PCF8563_REG_YR] = BIN2BCD(tm->tm_year % 100);
-       if (tm->tm_year < 100)
+       if (pcf8563->c_polarity ? (tm->tm_year >= 100) : (tm->tm_year < 100))
                buf[PCF8563_REG_MO] |= PCF8563_MO_C;
 
        buf[PCF8563_REG_DW] = tm->tm_wday & 0x07;
@@ -149,7 +163,7 @@ static int pcf8563_set_datetime(struct i2c_client *client, struct rtc_time *tm)
                if (err != sizeof(data)) {
                        dev_err(&client->dev,
                                "%s: err=%d addr=%02x, data=%02x\n",
-                               __FUNCTION__, err, data[0], data[1]);
+                               __func__, err, data[0], data[1]);
                        return -EIO;
                }
        };
@@ -194,7 +208,7 @@ static int pcf8563_validate_client(struct i2c_client *client)
                if (xfer != ARRAY_SIZE(msgs)) {
                        dev_err(&client->dev,
                                "%s: could not read register 0x%02X\n",
-                               __FUNCTION__, pattern[i].reg);
+                               __func__, pattern[i].reg);
 
                        return -EIO;
                }
@@ -206,7 +220,7 @@ static int pcf8563_validate_client(struct i2c_client *client)
                        dev_dbg(&client->dev,
                                "%s: pattern=%d, reg=%x, mask=0x%02x, min=%d, "
                                "max=%d, value=%d, raw=0x%02X\n",
-                               __FUNCTION__, i, pattern[i].reg, pattern[i].mask,
+                               __func__, i, pattern[i].reg, pattern[i].mask,
                                pattern[i].min, pattern[i].max,
                                value, buf);
 
@@ -232,97 +246,76 @@ static const struct rtc_class_ops pcf8563_rtc_ops = {
        .set_time       = pcf8563_rtc_set_time,
 };
 
-static int pcf8563_attach(struct i2c_adapter *adapter)
-{
-       return i2c_probe(adapter, &addr_data, pcf8563_probe);
-}
-
-static struct i2c_driver pcf8563_driver = {
-       .driver         = {
-               .name   = "pcf8563",
-       },
-       .id             = I2C_DRIVERID_PCF8563,
-       .attach_adapter = &pcf8563_attach,
-       .detach_client  = &pcf8563_detach,
-};
-
-static int pcf8563_probe(struct i2c_adapter *adapter, int address, int kind)
+static int pcf8563_probe(struct i2c_client *client,
+                               const struct i2c_device_id *id)
 {
-       struct i2c_client *client;
-       struct rtc_device *rtc;
+       struct pcf8563 *pcf8563;
 
        int err = 0;
 
-       dev_dbg(adapter->class_dev.dev, "%s\n", __FUNCTION__);
-
-       if (!i2c_check_functionality(adapter, I2C_FUNC_I2C)) {
-               err = -ENODEV;
-               goto exit;
-       }
-
-       if (!(client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL))) {
-               err = -ENOMEM;
-               goto exit;
-       }
+       dev_dbg(&client->dev, "%s\n", __func__);
 
-       client->addr = address;
-       client->driver = &pcf8563_driver;
-       client->adapter = adapter;
+       if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
+               return -ENODEV;
 
-       strlcpy(client->name, pcf8563_driver.driver.name, I2C_NAME_SIZE);
+       pcf8563 = kzalloc(sizeof(struct pcf8563), GFP_KERNEL);
+       if (!pcf8563)
+               return -ENOMEM;
 
        /* Verify the chip is really an PCF8563 */
-       if (kind < 0) {
-               if (pcf8563_validate_client(client) < 0) {
-                       err = -ENODEV;
-                       goto exit_kfree;
-               }
-       }
-
-       /* Inform the i2c layer */
-       if ((err = i2c_attach_client(client)))
+       if (pcf8563_validate_client(client) < 0) {
+               err = -ENODEV;
                goto exit_kfree;
+       }
 
        dev_info(&client->dev, "chip found, driver version " DRV_VERSION "\n");
 
-       rtc = rtc_device_register(pcf8563_driver.driver.name, &client->dev,
-                               &pcf8563_rtc_ops, THIS_MODULE);
+       pcf8563->rtc = rtc_device_register(pcf8563_driver.driver.name,
+                               &client->dev, &pcf8563_rtc_ops, THIS_MODULE);
 
-       if (IS_ERR(rtc)) {
-               err = PTR_ERR(rtc);
-               goto exit_detach;
+       if (IS_ERR(pcf8563->rtc)) {
+               err = PTR_ERR(pcf8563->rtc);
+               goto exit_kfree;
        }
 
-       i2c_set_clientdata(client, rtc);
+       i2c_set_clientdata(client, pcf8563);
 
        return 0;
 
-exit_detach:
-       i2c_detach_client(client);
-
 exit_kfree:
-       kfree(client);
+       kfree(pcf8563);
 
-exit:
        return err;
 }
 
-static int pcf8563_detach(struct i2c_client *client)
+static int pcf8563_remove(struct i2c_client *client)
 {
-       int err;
-       struct rtc_device *rtc = i2c_get_clientdata(client);
-
-       if (rtc)
-               rtc_device_unregister(rtc);
+       struct pcf8563 *pcf8563 = i2c_get_clientdata(client);
 
-       if ((err = i2c_detach_client(client)))
-               return err;
+       if (pcf8563->rtc)
+               rtc_device_unregister(pcf8563->rtc);
 
-       kfree(client);
+       kfree(pcf8563);
 
        return 0;
 }
 
+static const struct i2c_device_id pcf8563_id[] = {
+       { "pcf8563", 0 },
+       { "rtc8564", 0 },
+       { }
+};
+MODULE_DEVICE_TABLE(i2c, pcf8563_id);
+
+static struct i2c_driver pcf8563_driver = {
+       .driver         = {
+               .name   = "rtc-pcf8563",
+       },
+       .probe          = pcf8563_probe,
+       .remove         = pcf8563_remove,
+       .id_table       = pcf8563_id,
+};
+
 static int __init pcf8563_init(void)
 {
        return i2c_add_driver(&pcf8563_driver);