2 files changed, 262 insertions, 92 deletions

diff --git a/drivers/i2c/chips/Kconfig b/drivers/i2c/chips/Kconfig
index 7aa5c38f0855..87ee3ce58618 100644
--- a/drivers/i2c/chips/Kconfig
+++ b/drivers/i2c/chips/Kconfig
@@ -39,6 +39,7 @@ config SENSORS_EEPROM
 config SENSORS_PCF8574
         tristate "Philips PCF8574 and PCF8574A"
         depends on I2C && EXPERIMENTAL
+        default n
         help
           If you say yes here you get support for Philips PCF8574 and 
           PCF8574A chips.
@@ -46,6 +47,9 @@ config SENSORS_PCF8574
           This driver can also be built as a module.  If so, the module
           will be called pcf8574.
 
+          These devices are hard to detect and rarely found on mainstream
+          hardware.  If unsure, say N.
+
 config SENSORS_PCA9539
         tristate "Philips PCA9539 16-bit I/O port"
         depends on I2C && EXPERIMENTAL
@@ -59,12 +63,16 @@ config SENSORS_PCA9539
 config SENSORS_PCF8591
         tristate "Philips PCF8591"
         depends on I2C && EXPERIMENTAL
+        default n
         help
           If you say yes here you get support for Philips PCF8591 chips.
 
           This driver can also be built as a module.  If so, the module
           will be called pcf8591.
 
+          These devices are hard to detect and rarely found on mainstream
+          hardware.  If unsure, say N.
+
 config ISP1301_OMAP
         tristate "Philips ISP1301 with OMAP OTG"
         depends on I2C && ARCH_OMAP_OTG
diff --git a/drivers/i2c/chips/m41t00.c b/drivers/i2c/chips/m41t00.c
index 99ab4ec34390..2dd0a34d9472 100644
--- a/drivers/i2c/chips/m41t00.c
+++ b/drivers/i2c/chips/m41t00.c
@@ -1,11 +1,9 @@
 /*
- * drivers/i2c/chips/m41t00.c
- *
- * I2C client/driver for the ST M41T00 Real-Time Clock chip.
+ * I2C client/driver for the ST M41T00 family of i2c rtc chips.
  *
  * Author: Mark A. Greer <mgreer@mvista.com>
  *
- * 2005 (c) MontaVista Software, Inc. This file is licensed under
+ * 2005, 2006 (c) MontaVista Software, Inc. This file is licensed under
  * the terms of the GNU General Public License version 2. This program
  * is licensed "as is" without any warranty of any kind, whether express
  * or implied.
@@ -13,9 +11,6 @@
 /*
  * This i2c client/driver wedges between the drivers/char/genrtc.c RTC
  * interface and the SMBus interface of the i2c subsystem.
- * It would be more efficient to use i2c msgs/i2c_transfer directly but, as
- * recommened in .../Documentation/i2c/writing-clients section
- * "Sending and receiving", using SMBus level communication is preferred.
  */
 
 #include <linux/kernel.h>
@@ -24,56 +19,110 @@
 #include <linux/i2c.h>
 #include <linux/rtc.h>
 #include <linux/bcd.h>
-#include <linux/mutex.h>
 #include <linux/workqueue.h>
-
+#include <linux/platform_device.h>
+#include <linux/m41t00.h>
 #include <asm/time.h>
 #include <asm/rtc.h>
 
-#define M41T00_DRV_NAME         "m41t00"
-
-static DEFINE_MUTEX(m41t00_mutex);
-
 static struct i2c_driver m41t00_driver;
 static struct i2c_client *save_client;
 
 static unsigned short ignore[] = { I2C_CLIENT_END };
-static unsigned short normal_addr[] = { 0x68, I2C_CLIENT_END };
+static unsigned short normal_addr[] = { I2C_CLIENT_END, I2C_CLIENT_END };
 
 static struct i2c_client_address_data addr_data = {
-        .normal_i2c             = normal_addr,
-        .probe                  = ignore,
-        .ignore                 = ignore,
+        .normal_i2c     = normal_addr,
+        .probe          = ignore,
+        .ignore         = ignore,
+};
+
+struct m41t00_chip_info {
+        u8      type;
+        char    *name;
+        u8      read_limit;
+        u8      sec;            /* Offsets for chip regs */
+        u8      min;
+        u8      hour;
+        u8      day;
+        u8      mon;
+        u8      year;
+        u8      alarm_mon;
+        u8      alarm_hour;
+        u8      sqw;
+        u8      sqw_freq;
 };
 
+static struct m41t00_chip_info m41t00_chip_info_tbl[] = {
+        {
+                .type           = M41T00_TYPE_M41T00,
+                .name           = "m41t00",
+                .read_limit     = 5,
+                .sec            = 0,
+                .min            = 1,
+                .hour           = 2,
+                .day            = 4,
+                .mon            = 5,
+                .year           = 6,
+        },
+        {
+                .type           = M41T00_TYPE_M41T81,
+                .name           = "m41t81",
+                .read_limit     = 1,
+                .sec            = 1,
+                .min            = 2,
+                .hour           = 3,
+                .day            = 5,
+                .mon            = 6,
+                .year           = 7,
+                .alarm_mon      = 0xa,
+                .alarm_hour     = 0xc,
+                .sqw            = 0x13,
+        },
+        {
+                .type           = M41T00_TYPE_M41T85,
+                .name           = "m41t85",
+                .read_limit     = 1,
+                .sec            = 1,
+                .min            = 2,
+                .hour           = 3,
+                .day            = 5,
+                .mon            = 6,
+                .year           = 7,
+                .alarm_mon      = 0xa,
+                .alarm_hour     = 0xc,
+                .sqw            = 0x13,
+        },
+};
+static struct m41t00_chip_info *m41t00_chip;
+
 ulong
 m41t00_get_rtc_time(void)
 {
-        s32     sec, min, hour, day, mon, year;
-        s32     sec1, min1, hour1, day1, mon1, year1;
-        ulong   limit = 10;
+        s32 sec, min, hour, day, mon, year;
+        s32 sec1, min1, hour1, day1, mon1, year1;
+        u8 reads = 0;
+        u8 buf[8], msgbuf[1] = { 0 }; /* offset into rtc's regs */
+        struct i2c_msg msgs[] = {
+                {
+                        .addr   = save_client->addr,
+                        .flags  = 0,
+                        .len    = 1,
+                        .buf    = msgbuf,
+                },
+                {
+                        .addr   = save_client->addr,
+                        .flags  = I2C_M_RD,
+                        .len    = 8,
+                        .buf    = buf,
+                },
+        };
 
         sec = min = hour = day = mon = year = 0;
-        sec1 = min1 = hour1 = day1 = mon1 = year1 = 0;
 
-        mutex_lock(&m41t00_mutex);
         do {
-                if (((sec = i2c_smbus_read_byte_data(save_client, 0)) >= 0)
-                        && ((min = i2c_smbus_read_byte_data(save_client, 1))
-                                >= 0)
-                        && ((hour = i2c_smbus_read_byte_data(save_client, 2))
-                                >= 0)
-                        && ((day = i2c_smbus_read_byte_data(save_client, 4))
-                                >= 0)
-                        && ((mon = i2c_smbus_read_byte_data(save_client, 5))
-                                >= 0)
-                        && ((year = i2c_smbus_read_byte_data(save_client, 6))
-                                >= 0)
-                        && ((sec == sec1) && (min == min1) && (hour == hour1)
-                                && (day == day1) && (mon == mon1)
-                                && (year == year1)))
-
-                                break;
+                if (i2c_transfer(save_client->adapter, msgs, 2) < 0)
+                        goto read_err;
 
                 sec1 = sec;
                 min1 = min;
@@ -81,69 +130,88 @@ m41t00_get_rtc_time(void)
                 day1 = day;
                 mon1 = mon;
                 year1 = year;
-        } while (--limit > 0);
-        mutex_unlock(&m41t00_mutex);
-
-        if (limit == 0) {
-                dev_warn(&save_client->dev,
-                        "m41t00: can't read rtc chip\n");
-                sec = min = hour = day = mon = year = 0;
-        }
-
-        sec &= 0x7f;
-        min &= 0x7f;
-        hour &= 0x3f;
-        day &= 0x3f;
-        mon &= 0x1f;
-        year &= 0xff;
 
-        BCD_TO_BIN(sec);
-        BCD_TO_BIN(min);
-        BCD_TO_BIN(hour);
-        BCD_TO_BIN(day);
-        BCD_TO_BIN(mon);
-        BCD_TO_BIN(year);
+                sec = buf[m41t00_chip->sec] & 0x7f;
+                min = buf[m41t00_chip->min] & 0x7f;
+                hour = buf[m41t00_chip->hour] & 0x3f;
+                day = buf[m41t00_chip->day] & 0x3f;
+                mon = buf[m41t00_chip->mon] & 0x1f;
+                year = buf[m41t00_chip->year];
+        } while ((++reads < m41t00_chip->read_limit) && ((sec != sec1)
+                        || (min != min1) || (hour != hour1) || (day != day1)
+                        || (mon != mon1) || (year != year1)));
+
+        if ((m41t00_chip->read_limit > 1) && ((sec != sec1) || (min != min1)
+                        || (hour != hour1) || (day != day1) || (mon != mon1)
+                        || (year != year1)))
+                goto read_err;
+
+        sec = BCD2BIN(sec);
+        min = BCD2BIN(min);
+        hour = BCD2BIN(hour);
+        day = BCD2BIN(day);
+        mon = BCD2BIN(mon);
+        year = BCD2BIN(year);
 
         year += 1900;
         if (year < 1970)
                 year += 100;
 
         return mktime(year, mon, day, hour, min, sec);
+
+read_err:
+        dev_err(&save_client->dev, "m41t00_get_rtc_time: Read error\n");
+        return 0;
 }
+EXPORT_SYMBOL_GPL(m41t00_get_rtc_time);
 
 static void
 m41t00_set(void *arg)
 {
         struct rtc_time tm;
-        ulong   nowtime = *(ulong *)arg;
+        int nowtime = *(int *)arg;
+        s32 sec, min, hour, day, mon, year;
+        u8 wbuf[9], *buf = &wbuf[1], msgbuf[1] = { 0 };
+        struct i2c_msg msgs[] = {
+                {
+                        .addr   = save_client->addr,
+                        .flags  = 0,
+                        .len    = 1,
+                        .buf    = msgbuf,
+                },
+                {
+                        .addr   = save_client->addr,
+                        .flags  = I2C_M_RD,
+                        .len    = 8,
+                        .buf    = buf,
+                },
+        };
 
         to_tm(nowtime, &tm);
         tm.tm_year = (tm.tm_year - 1900) % 100;
 
-        BIN_TO_BCD(tm.tm_sec);
-        BIN_TO_BCD(tm.tm_min);
-        BIN_TO_BCD(tm.tm_hour);
-        BIN_TO_BCD(tm.tm_mon);
-        BIN_TO_BCD(tm.tm_mday);
-        BIN_TO_BCD(tm.tm_year);
-
-        mutex_lock(&m41t00_mutex);
-        if ((i2c_smbus_write_byte_data(save_client, 0, tm.tm_sec & 0x7f) < 0)
-                || (i2c_smbus_write_byte_data(save_client, 1, tm.tm_min & 0x7f)
-                        < 0)
-                || (i2c_smbus_write_byte_data(save_client, 2, tm.tm_hour & 0x3f)
-                        < 0)
-                || (i2c_smbus_write_byte_data(save_client, 4, tm.tm_mday & 0x3f)
-                        < 0)
-                || (i2c_smbus_write_byte_data(save_client, 5, tm.tm_mon & 0x1f)
-                        < 0)
-                || (i2c_smbus_write_byte_data(save_client, 6, tm.tm_year & 0xff)
-                        < 0))
-
-                dev_warn(&save_client->dev,"m41t00: can't write to rtc chip\n");
-
-        mutex_unlock(&m41t00_mutex);
-        return;
+        sec = BIN2BCD(tm.tm_sec);
+        min = BIN2BCD(tm.tm_min);
+        hour = BIN2BCD(tm.tm_hour);
+        day = BIN2BCD(tm.tm_mday);
+        mon = BIN2BCD(tm.tm_mon);
+        year = BIN2BCD(tm.tm_year);
+
+        /* Read reg values into buf[0..7]/wbuf[1..8] */
+        if (i2c_transfer(save_client->adapter, msgs, 2) < 0) {
+                dev_err(&save_client->dev, "m41t00_set: Read error\n");
+                return;
+        }
+
+        wbuf[0] = 0; /* offset into rtc's regs */
+        buf[m41t00_chip->sec] = (buf[m41t00_chip->sec] & ~0x7f) | (sec & 0x7f);
+        buf[m41t00_chip->min] = (buf[m41t00_chip->min] & ~0x7f) | (min & 0x7f);
+        buf[m41t00_chip->hour] = (buf[m41t00_chip->hour] & ~0x3f) | (hour& 0x3f);
+        buf[m41t00_chip->day] = (buf[m41t00_chip->day] & ~0x3f) | (day & 0x3f);
+        buf[m41t00_chip->mon] = (buf[m41t00_chip->mon] & ~0x1f) | (mon & 0x1f);
+
+        if (i2c_master_send(save_client, wbuf, 9) < 0)
+                dev_err(&save_client->dev, "m41t00_set: Write error\n");
 }
 
 static ulong new_time;
@@ -162,6 +230,48 @@ m41t00_set_rtc_time(ulong nowtime)
 
         return 0;
 }
+EXPORT_SYMBOL_GPL(m41t00_set_rtc_time);
+
+/*
+ *****************************************************************************
+ *
+ *      platform_data Driver Interface
+ *
+ *****************************************************************************
+ */
+static int __init
+m41t00_platform_probe(struct platform_device *pdev)
+{
+        struct m41t00_platform_data *pdata;
+        int i;
+
+        if (pdev && (pdata = pdev->dev.platform_data)) {
+                normal_addr[0] = pdata->i2c_addr;
+
+                for (i=0; i<ARRAY_SIZE(m41t00_chip_info_tbl); i++)
+                        if (m41t00_chip_info_tbl[i].type == pdata->type) {
+                                m41t00_chip = &m41t00_chip_info_tbl[i];
+                                m41t00_chip->sqw_freq = pdata->sqw_freq;
+                                return 0;
+                        }
+        }
+        return -ENODEV;
+}
+
+static int __exit
+m41t00_platform_remove(struct platform_device *pdev)
+{
+        return 0;
+}
+
+static struct platform_driver m41t00_platform_driver = {
+        .probe  = m41t00_platform_probe,
+        .remove = m41t00_platform_remove,
+        .driver = {
+                .owner = THIS_MODULE,
+                .name  = M41T00_DRV_NAME,
+        },
+};
 
 /*
  *****************************************************************************
@@ -176,23 +286,71 @@ m41t00_probe(struct i2c_adapter *adap, int addr, int kind)
         struct i2c_client *client;
         int rc;
 
+        if (!i2c_check_functionality(adap, I2C_FUNC_I2C
+                        | I2C_FUNC_SMBUS_BYTE_DATA))
+                return 0;
+
         client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL);
         if (!client)
                 return -ENOMEM;
 
-        strncpy(client->name, M41T00_DRV_NAME, I2C_NAME_SIZE);
+        strlcpy(client->name, m41t00_chip->name, I2C_NAME_SIZE);
         client->addr = addr;
         client->adapter = adap;
         client->driver = &m41t00_driver;
 
-        if ((rc = i2c_attach_client(client)) != 0) {
-                kfree(client);
-                return rc;
+        if ((rc = i2c_attach_client(client)))
+                goto attach_err;
+
+        if (m41t00_chip->type != M41T00_TYPE_M41T00) {
+                /* If asked, disable SQW, set SQW frequency & re-enable */
+                if (m41t00_chip->sqw_freq)
+                        if (((rc = i2c_smbus_read_byte_data(client,
+                                        m41t00_chip->alarm_mon)) < 0)
+                         || ((rc = i2c_smbus_write_byte_data(client,
+                                        m41t00_chip->alarm_mon, rc & ~0x40)) <0)
+                         || ((rc = i2c_smbus_write_byte_data(client,
+                                        m41t00_chip->sqw,
+                                        m41t00_chip->sqw_freq)) < 0)
+                         || ((rc = i2c_smbus_write_byte_data(client,
+                                        m41t00_chip->alarm_mon, rc | 0x40)) <0))
+                                goto sqw_err;
+
+                /* Make sure HT (Halt Update) bit is cleared */
+                if ((rc = i2c_smbus_read_byte_data(client,
+                                m41t00_chip->alarm_hour)) < 0)
+                        goto ht_err;
+
+                if (rc & 0x40)
+                        if ((rc = i2c_smbus_write_byte_data(client,
+                                        m41t00_chip->alarm_hour, rc & ~0x40))<0)
+                                goto ht_err;
         }
 
-        m41t00_wq = create_singlethread_workqueue("m41t00");
+        /* Make sure ST (stop) bit is cleared */
+        if ((rc = i2c_smbus_read_byte_data(client, m41t00_chip->sec)) < 0)
+                goto st_err;
+
+        if (rc & 0x80)
+                if ((rc = i2c_smbus_write_byte_data(client, m41t00_chip->sec,
+                                rc & ~0x80)) < 0)
+                        goto st_err;
+
+        m41t00_wq = create_singlethread_workqueue(m41t00_chip->name);
         save_client = client;
         return 0;
+
+st_err:
+        dev_err(&client->dev, "m41t00_probe: Can't clear ST bit\n");
+        goto attach_err;
+ht_err:
+        dev_err(&client->dev, "m41t00_probe: Can't clear HT bit\n");
+        goto attach_err;
+sqw_err:
+        dev_err(&client->dev, "m41t00_probe: Can't set SQW Frequency\n");
+attach_err:
+        kfree(client);
+        return rc;
 }
 
 static int
@@ -204,7 +362,7 @@ m41t00_attach(struct i2c_adapter *adap)
 static int
 m41t00_detach(struct i2c_client *client)
 {
-        int     rc;
+        int rc;
 
         if ((rc = i2c_detach_client(client)) == 0) {
                 kfree(client);
@@ -225,14 +383,18 @@ static struct i2c_driver m41t00_driver = {
 static int __init
 m41t00_init(void)
 {
-        return i2c_add_driver(&m41t00_driver);
+        int rc;
+
+        if (!(rc = platform_driver_register(&m41t00_platform_driver)))
+                rc = i2c_add_driver(&m41t00_driver);
+        return rc;
 }
 
 static void __exit
 m41t00_exit(void)
 {
         i2c_del_driver(&m41t00_driver);
-        return;
+        platform_driver_unregister(&m41t00_platform_driver);
 }
 
 module_init(m41t00_init);