X-Git-Url: https://git.proxmox.com/?a=blobdiff_plain;f=drivers%2Frtc%2Frtc-pcf85063.c;h=e8ddbb359d11951f0d9592895a23699941280412;hb=631476d7fd93cc1cde1fc9ea6b3875f8eca79871;hp=63334cbeca41d8233b55e674e120ec4bd895a45a;hpb=e219aafe50fd546b8686582ddbafd24c3c2eda04;p=mirror_ubuntu-artful-kernel.git diff --git a/drivers/rtc/rtc-pcf85063.c b/drivers/rtc/rtc-pcf85063.c index 63334cbeca41..e8ddbb359d11 100644 --- a/drivers/rtc/rtc-pcf85063.c +++ b/drivers/rtc/rtc-pcf85063.c @@ -16,12 +16,12 @@ #include #include -#define DRV_VERSION "0.0.1" - #define PCF85063_REG_CTRL1 0x00 /* status */ +#define PCF85063_REG_CTRL1_STOP BIT(5) #define PCF85063_REG_CTRL2 0x01 #define PCF85063_REG_SC 0x04 /* datetime */ +#define PCF85063_REG_SC_OS 0x80 #define PCF85063_REG_MN 0x05 #define PCF85063_REG_HR 0x06 #define PCF85063_REG_DM 0x07 @@ -29,15 +29,31 @@ #define PCF85063_REG_MO 0x09 #define PCF85063_REG_YR 0x0A -#define PCF85063_MO_C 0x80 /* century */ - static struct i2c_driver pcf85063_driver; -struct pcf85063 { - struct rtc_device *rtc; - int c_polarity; /* 0: MO_C=1 means 19xx, otherwise MO_C=1 means 20xx */ - int voltage_low; /* indicates if a low_voltage was detected */ -}; +static int pcf85063_stop_clock(struct i2c_client *client, u8 *ctrl1) +{ + s32 ret; + + ret = i2c_smbus_read_byte_data(client, PCF85063_REG_CTRL1); + if (ret < 0) { + dev_err(&client->dev, "Failing to stop the clock\n"); + return -EIO; + } + + /* stop the clock */ + ret |= PCF85063_REG_CTRL1_STOP; + + ret = i2c_smbus_write_byte_data(client, PCF85063_REG_CTRL1, ret); + if (ret < 0) { + dev_err(&client->dev, "Failing to stop the clock\n"); + return -EIO; + } + + *ctrl1 = ret; + + return 0; +} /* * In the routines that deal directly with the pcf85063 hardware, we use @@ -45,81 +61,85 @@ struct pcf85063 { */ static int pcf85063_get_datetime(struct i2c_client *client, struct rtc_time *tm) { - struct pcf85063 *pcf85063 = i2c_get_clientdata(client); - unsigned char buf[13] = { PCF85063_REG_CTRL1 }; - struct i2c_msg msgs[] = { - {/* setup read ptr */ - .addr = client->addr, - .len = 1, - .buf = buf - }, - {/* read status + date */ - .addr = client->addr, - .flags = I2C_M_RD, - .len = 13, - .buf = buf - }, - }; - - /* read registers */ - if ((i2c_transfer(client->adapter, msgs, 2)) != 2) { - dev_err(&client->dev, "%s: read error\n", __func__); + int rc; + u8 regs[7]; + + /* + * while reading, the time/date registers are blocked and not updated + * anymore until the access is finished. To not lose a second + * event, the access must be finished within one second. So, read all + * time/date registers in one turn. + */ + rc = i2c_smbus_read_i2c_block_data(client, PCF85063_REG_SC, + sizeof(regs), regs); + if (rc != sizeof(regs)) { + dev_err(&client->dev, "date/time register read error\n"); return -EIO; } - tm->tm_sec = bcd2bin(buf[PCF85063_REG_SC] & 0x7F); - tm->tm_min = bcd2bin(buf[PCF85063_REG_MN] & 0x7F); - tm->tm_hour = bcd2bin(buf[PCF85063_REG_HR] & 0x3F); /* rtc hr 0-23 */ - tm->tm_mday = bcd2bin(buf[PCF85063_REG_DM] & 0x3F); - tm->tm_wday = buf[PCF85063_REG_DW] & 0x07; - tm->tm_mon = bcd2bin(buf[PCF85063_REG_MO] & 0x1F) - 1; /* rtc mn 1-12 */ - tm->tm_year = bcd2bin(buf[PCF85063_REG_YR]); + /* if the clock has lost its power it makes no sense to use its time */ + if (regs[0] & PCF85063_REG_SC_OS) { + dev_warn(&client->dev, "Power loss detected, invalid time\n"); + return -EINVAL; + } + + tm->tm_sec = bcd2bin(regs[0] & 0x7F); + tm->tm_min = bcd2bin(regs[1] & 0x7F); + tm->tm_hour = bcd2bin(regs[2] & 0x3F); /* rtc hr 0-23 */ + tm->tm_mday = bcd2bin(regs[3] & 0x3F); + tm->tm_wday = regs[4] & 0x07; + tm->tm_mon = bcd2bin(regs[5] & 0x1F) - 1; /* rtc mn 1-12 */ + tm->tm_year = bcd2bin(regs[6]); if (tm->tm_year < 70) tm->tm_year += 100; /* assume we are in 1970...2069 */ - /* detect the polarity heuristically. see note above. */ - pcf85063->c_polarity = (buf[PCF85063_REG_MO] & PCF85063_MO_C) ? - (tm->tm_year >= 100) : (tm->tm_year < 100); return rtc_valid_tm(tm); } static int pcf85063_set_datetime(struct i2c_client *client, struct rtc_time *tm) { - int i = 0, err = 0; - unsigned char buf[11]; + int rc; + u8 regs[8]; - /* Control & status */ - buf[PCF85063_REG_CTRL1] = 0; - buf[PCF85063_REG_CTRL2] = 5; + /* + * to accurately set the time, reset the divider chain and keep it in + * reset state until all time/date registers are written + */ + rc = pcf85063_stop_clock(client, ®s[7]); + if (rc != 0) + return rc; /* hours, minutes and seconds */ - buf[PCF85063_REG_SC] = bin2bcd(tm->tm_sec) & 0x7F; + regs[0] = bin2bcd(tm->tm_sec) & 0x7F; /* clear OS flag */ - buf[PCF85063_REG_MN] = bin2bcd(tm->tm_min); - buf[PCF85063_REG_HR] = bin2bcd(tm->tm_hour); + regs[1] = bin2bcd(tm->tm_min); + regs[2] = bin2bcd(tm->tm_hour); /* Day of month, 1 - 31 */ - buf[PCF85063_REG_DM] = bin2bcd(tm->tm_mday); + regs[3] = bin2bcd(tm->tm_mday); /* Day, 0 - 6 */ - buf[PCF85063_REG_DW] = tm->tm_wday & 0x07; + regs[4] = tm->tm_wday & 0x07; /* month, 1 - 12 */ - buf[PCF85063_REG_MO] = bin2bcd(tm->tm_mon + 1); + regs[5] = bin2bcd(tm->tm_mon + 1); /* year and century */ - buf[PCF85063_REG_YR] = bin2bcd(tm->tm_year % 100); - - /* write register's data */ - for (i = 0; i < sizeof(buf); i++) { - unsigned char data[2] = { i, buf[i] }; - - err = i2c_master_send(client, data, sizeof(data)); - if (err != sizeof(data)) { - dev_err(&client->dev, "%s: err=%d addr=%02x, data=%02x\n", - __func__, err, data[0], data[1]); - return -EIO; - } + regs[6] = bin2bcd(tm->tm_year % 100); + + /* + * after all time/date registers are written, let the 'address auto + * increment' feature wrap around and write register CTRL1 to re-enable + * the clock divider chain again + */ + regs[7] &= ~PCF85063_REG_CTRL1_STOP; + + /* write all registers at once */ + rc = i2c_smbus_write_i2c_block_data(client, PCF85063_REG_SC, + sizeof(regs), regs); + if (rc < 0) { + dev_err(&client->dev, "date/time register write error\n"); + return rc; } return 0; @@ -143,27 +163,18 @@ static const struct rtc_class_ops pcf85063_rtc_ops = { static int pcf85063_probe(struct i2c_client *client, const struct i2c_device_id *id) { - struct pcf85063 *pcf85063; + struct rtc_device *rtc; dev_dbg(&client->dev, "%s\n", __func__); if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) return -ENODEV; - pcf85063 = devm_kzalloc(&client->dev, sizeof(struct pcf85063), - GFP_KERNEL); - if (!pcf85063) - return -ENOMEM; - - dev_info(&client->dev, "chip found, driver version " DRV_VERSION "\n"); - - i2c_set_clientdata(client, pcf85063); - - pcf85063->rtc = devm_rtc_device_register(&client->dev, - pcf85063_driver.driver.name, - &pcf85063_rtc_ops, THIS_MODULE); + rtc = devm_rtc_device_register(&client->dev, + pcf85063_driver.driver.name, + &pcf85063_rtc_ops, THIS_MODULE); - return PTR_ERR_OR_ZERO(pcf85063->rtc); + return PTR_ERR_OR_ZERO(rtc); } static const struct i2c_device_id pcf85063_id[] = { @@ -194,4 +205,3 @@ module_i2c_driver(pcf85063_driver); MODULE_AUTHOR("Søren Andersen "); MODULE_DESCRIPTION("PCF85063 RTC driver"); MODULE_LICENSE("GPL"); -MODULE_VERSION(DRV_VERSION);