/*
- * 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.
/*
* 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>
#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;
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_tlet(ulong arg)
+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 & 0x7f)
- < 0)
- || (i2c_smbus_write_byte_data(save_client, 4, tm.tm_mday & 0x7f)
- < 0)
- || (i2c_smbus_write_byte_data(save_client, 5, tm.tm_mon & 0x7f)
- < 0)
- || (i2c_smbus_write_byte_data(save_client, 6, tm.tm_year & 0x7f)
- < 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;
+static ulong new_time;
+/* well, isn't this API just _lovely_? */
+static void
+m41t00_barf(struct work_struct *unusable)
+{
+ m41t00_set(&new_time);
+}
-DECLARE_TASKLET_DISABLED(m41t00_tasklet, m41t00_set_tlet, (ulong)&new_time);
+static struct workqueue_struct *m41t00_wq;
+static DECLARE_WORK(m41t00_work, m41t00_barf);
int
m41t00_set_rtc_time(ulong nowtime)
new_time = nowtime;
if (in_interrupt())
- tasklet_schedule(&m41t00_tasklet);
+ queue_work(m41t00_wq, &m41t00_work);
else
- m41t00_set_tlet((ulong)&new_time);
+ m41t00_set(&new_time);
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,
+ },
+};
/*
*****************************************************************************
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;
}
+ /* 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
static int
m41t00_detach(struct i2c_client *client)
{
- int rc;
+ int rc;
if ((rc = i2c_detach_client(client)) == 0) {
kfree(client);
- tasklet_kill(&m41t00_tasklet);
+ destroy_workqueue(m41t00_wq);
}
return rc;
}
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);
git.openpandora.org / pandora-kernel.git / blobdiff