diff options
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/i2c/chips/m41t00.c | 313 |
1 files changed, 241 insertions, 72 deletions
diff --git a/drivers/i2c/chips/m41t00.c b/drivers/i2c/chips/m41t00.c index eb2be3e4416c..2dd0a34d9472 100644 --- a/drivers/i2c/chips/m41t00.c +++ b/drivers/i2c/chips/m41t00.c @@ -1,9 +1,9 @@ /* - * 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. @@ -19,21 +19,17 @@ #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, @@ -41,34 +37,92 @@ static struct i2c_client_address_data addr_data = { .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; + 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; @@ -76,21 +130,21 @@ 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; + 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); @@ -104,40 +158,60 @@ m41t00_get_rtc_time(void) 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; - tm.tm_sec = BIN2BCD(tm.tm_sec); - tm.tm_min = BIN2BCD(tm.tm_min); - tm.tm_hour = BIN2BCD(tm.tm_hour); - tm.tm_mon = BIN2BCD(tm.tm_mon); - tm.tm_mday = BIN2BCD(tm.tm_mday); - tm.tm_year = BIN2BCD(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); + 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; @@ -156,6 +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, + }, +}; /* ***************************************************************************** @@ -170,23 +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; - strlcpy(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 @@ -219,13 +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); + platform_driver_unregister(&m41t00_platform_driver); } module_init(m41t00_init); |