From: Maciej W. Rozycki <macro@xxxxxxxxxxxxxx> Tested-by: Matt Turner <mattst88@xxxxxxxxx> Signed-off-by: Matt Turner <mattst88@xxxxxxxxx> --- drivers/rtc/rtc-m41t80.c | 251 ++++++++++++++++++++-------------------------- 1 files changed, 107 insertions(+), 144 deletions(-) diff --git a/drivers/rtc/rtc-m41t80.c b/drivers/rtc/rtc-m41t80.c index 5a8daa3..2233ed5 100644 --- a/drivers/rtc/rtc-m41t80.c +++ b/drivers/rtc/rtc-m41t80.c @@ -6,6 +6,7 @@ * Based on m41t00.c by Mark A. Greer <mgreer@xxxxxxxxxx> * * 2006 (c) mycable GmbH + * Copyright (c) 2008 Maciej W. Rozycki * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as @@ -38,6 +39,8 @@ #define M41T80_REG_DAY 5 #define M41T80_REG_MON 6 #define M41T80_REG_YEAR 7 +#define M41T80_REG_CONTROL 8 +#define M41T80_REG_WATCHDOG 9 #define M41T80_REG_ALARM_MON 0xa #define M41T80_REG_ALARM_DAY 0xb #define M41T80_REG_ALARM_HOUR 0xc @@ -66,7 +69,7 @@ #define M41T80_FEATURE_WD (1 << 3) /* Extra watchdog resolution */ #define M41T80_FEATURE_SQ_ALT (1 << 4) /* RSx bits are in reg 4 */ -#define DRV_VERSION "0.05" +#define DRV_VERSION "0.06" static DEFINE_MUTEX(m41t80_rtc_mutex); static const struct i2c_device_id m41t80_id[] = { @@ -89,31 +92,89 @@ struct m41t80_data { struct rtc_device *rtc; }; -static int m41t80_get_datetime(struct i2c_client *client, - struct rtc_time *tm) + +static int m41t80_write_block_data(struct i2c_client *client, + u8 reg, u8 num, u8 *buf) { - u8 buf[M41T80_DATETIME_REG_SIZE], dt_addr[1] = { M41T80_REG_SEC }; - struct i2c_msg msgs[] = { - { - .addr = client->addr, - .flags = 0, - .len = 1, - .buf = dt_addr, - }, - { - .addr = client->addr, - .flags = I2C_M_RD, - .len = M41T80_DATETIME_REG_SIZE - M41T80_REG_SEC, - .buf = buf + M41T80_REG_SEC, - }, - }; + int i, rc; + + if (i2c_check_functionality(client->adapter, + I2C_FUNC_SMBUS_WRITE_I2C_BLOCK)) { + i = i2c_smbus_write_i2c_block_data(client, reg, num, buf); + } else { + for (i = 0; i < num; i++) { + rc = i2c_smbus_write_byte_data(client, reg + i, + buf[i]); + if (rc < 0) { + i = rc; + goto out; + } + } + } +out: + return i; +} - if (i2c_transfer(client->adapter, msgs, 2) < 0) { - dev_err(&client->dev, "read error\n"); - return -EIO; +static int m41t80_read_block_data(struct i2c_client *client, + u8 reg, u8 num, u8 *buf) +{ + int i, rc; + + if (i2c_check_functionality(client->adapter, + I2C_FUNC_SMBUS_READ_I2C_BLOCK)) { + i = i2c_smbus_read_i2c_block_data(client, reg, num, buf); + } else { + for (i = 0; i < num; i++) { + rc = i2c_smbus_read_byte_data(client, reg + i); + if (rc < 0) { + i = rc; + goto out; + } + buf[i] = rc; + } } +out: + return i; +} + +static int m41t80_get_datetime(struct i2c_client *client, struct rtc_time *tm) +{ + u8 buf[M41T80_DATETIME_REG_SIZE]; + int loops = 2; + int sec0, sec1; + + /* + * Time registers are latched by this chip if an I2C block + * transfer is used, but with SMBus-style byte accesses + * this is not the case, so check seconds for a wraparound. + */ + do { + if (m41t80_read_block_data(client, M41T80_REG_SEC, + M41T80_DATETIME_REG_SIZE - + M41T80_REG_SEC, + buf + M41T80_REG_SEC) < 0) { + dev_err(&client->dev, "read error\n"); + return -EIO; + } + if (i2c_check_functionality(client->adapter, + I2C_FUNC_SMBUS_READ_I2C_BLOCK)) { + sec1 = buf[M41T80_REG_SEC]; + break; + } + + sec0 = buf[M41T80_REG_SEC]; + sec1 = i2c_smbus_read_byte_data(client, M41T80_REG_SEC); + if (sec1 < 0) { + dev_err(&client->dev, "read error\n"); + return -EIO; + } + + sec0 = bcd2bin(sec0 & 0x7f); + sec1 = bcd2bin(sec1 & 0x7f); + } while (sec1 < sec0 && --loops); - tm->tm_sec = bcd2bin(buf[M41T80_REG_SEC] & 0x7f); + tm->tm_sec = sec1; + tm->tm_min = bcd2bin(buf[M41T80_REG_MIN] & 0x7f); tm->tm_min = bcd2bin(buf[M41T80_REG_MIN] & 0x7f); tm->tm_hour = bcd2bin(buf[M41T80_REG_HOUR] & 0x3f); tm->tm_mday = bcd2bin(buf[M41T80_REG_DAY] & 0x3f); @@ -128,39 +189,16 @@ static int m41t80_get_datetime(struct i2c_client *client, /* Sets the given date and time to the real time clock. */ static int m41t80_set_datetime(struct i2c_client *client, struct rtc_time *tm) { - u8 wbuf[1 + M41T80_DATETIME_REG_SIZE]; - u8 *buf = &wbuf[1]; - u8 dt_addr[1] = { M41T80_REG_SEC }; - struct i2c_msg msgs_in[] = { - { - .addr = client->addr, - .flags = 0, - .len = 1, - .buf = dt_addr, - }, - { - .addr = client->addr, - .flags = I2C_M_RD, - .len = M41T80_DATETIME_REG_SIZE - M41T80_REG_SEC, - .buf = buf + M41T80_REG_SEC, - }, - }; - struct i2c_msg msgs[] = { - { - .addr = client->addr, - .flags = 0, - .len = 1 + M41T80_DATETIME_REG_SIZE, - .buf = wbuf, - }, - }; + u8 buf[M41T80_DATETIME_REG_SIZE]; /* Read current reg values into buf[1..7] */ - if (i2c_transfer(client->adapter, msgs_in, 2) < 0) { + if (m41t80_read_block_data(client, M41T80_REG_SEC, + M41T80_DATETIME_REG_SIZE - M41T80_REG_SEC, + buf + M41T80_REG_SEC) < 0) { dev_err(&client->dev, "read error\n"); return -EIO; } - wbuf[0] = 0; /* offset into rtc's regs */ /* Merge time-data and register flags into buf[0..7] */ buf[M41T80_REG_SSEC] = 0; buf[M41T80_REG_SEC] = @@ -177,8 +215,8 @@ static int m41t80_set_datetime(struct i2c_client *client, struct rtc_time *tm) bin2bcd(tm->tm_mon + 1) | (buf[M41T80_REG_MON] & ~0x1f); /* assume 20YY not 19YY */ buf[M41T80_REG_YEAR] = bin2bcd(tm->tm_year % 100); - - if (i2c_transfer(client->adapter, msgs, 1) != 1) { + if (m41t80_write_block_data(client, M41T80_REG_SSEC, + M41T80_DATETIME_REG_SIZE, buf) < 0) { dev_err(&client->dev, "write error\n"); return -EIO; } @@ -252,34 +290,11 @@ err: static int m41t80_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *t) { struct i2c_client *client = to_i2c_client(dev); - u8 wbuf[1 + M41T80_ALARM_REG_SIZE]; - u8 *buf = &wbuf[1]; + u8 buf[M41T80_ALARM_REG_SIZE]; u8 *reg = buf - M41T80_REG_ALARM_MON; - u8 dt_addr[1] = { M41T80_REG_ALARM_MON }; - struct i2c_msg msgs_in[] = { - { - .addr = client->addr, - .flags = 0, - .len = 1, - .buf = dt_addr, - }, - { - .addr = client->addr, - .flags = I2C_M_RD, - .len = M41T80_ALARM_REG_SIZE, - .buf = buf, - }, - }; - struct i2c_msg msgs[] = { - { - .addr = client->addr, - .flags = 0, - .len = 1 + M41T80_ALARM_REG_SIZE, - .buf = wbuf, - }, - }; - if (i2c_transfer(client->adapter, msgs_in, 2) < 0) { + if (m41t80_read_block_data(client, M41T80_REG_ALARM_MON, + M41T80_ALARM_REG_SIZE, buf) < 0) { dev_err(&client->dev, "read error\n"); return -EIO; } @@ -289,7 +304,6 @@ static int m41t80_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *t) reg[M41T80_REG_ALARM_MIN] = 0; reg[M41T80_REG_ALARM_SEC] = 0; - wbuf[0] = M41T80_REG_ALARM_MON; /* offset into rtc's regs */ reg[M41T80_REG_ALARM_SEC] |= t->time.tm_sec >= 0 ? bin2bcd(t->time.tm_sec) : 0x80; reg[M41T80_REG_ALARM_MIN] |= t->time.tm_min >= 0 ? @@ -303,7 +317,8 @@ static int m41t80_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *t) else reg[M41T80_REG_ALARM_DAY] |= 0x40; - if (i2c_transfer(client->adapter, msgs, 1) != 1) { + if (m41t80_write_block_data(client, M41T80_REG_ALARM_MON, + M41T80_ALARM_REG_SIZE, buf) < 0) { dev_err(&client->dev, "write error\n"); return -EIO; } @@ -323,24 +338,10 @@ static int m41t80_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *t) { struct i2c_client *client = to_i2c_client(dev); u8 buf[M41T80_ALARM_REG_SIZE + 1]; /* all alarm regs and flags */ - u8 dt_addr[1] = { M41T80_REG_ALARM_MON }; u8 *reg = buf - M41T80_REG_ALARM_MON; - struct i2c_msg msgs[] = { - { - .addr = client->addr, - .flags = 0, - .len = 1, - .buf = dt_addr, - }, - { - .addr = client->addr, - .flags = I2C_M_RD, - .len = M41T80_ALARM_REG_SIZE + 1, - .buf = buf, - }, - }; - if (i2c_transfer(client->adapter, msgs, 2) < 0) { + if (m41t80_read_block_data(client, M41T80_REG_ALARM_MON, + M41T80_ALARM_REG_SIZE + 1, buf) < 0) { dev_err(&client->dev, "read error\n"); return -EIO; } @@ -513,26 +514,16 @@ static int boot_flag; */ static void wdt_ping(void) { - unsigned char i2c_data[2]; - struct i2c_msg msgs1[1] = { - { - .addr = save_client->addr, - .flags = 0, - .len = 2, - .buf = i2c_data, - }, - }; - struct m41t80_data *clientdata = i2c_get_clientdata(save_client); + u8 wdt = 0x80; /* WDS = 1 (0x80) */ - i2c_data[0] = 0x09; /* watchdog register */ + struct m41t80_data *clientdata = i2c_get_clientdata(save_client); if (wdt_margin > 31) - i2c_data[1] = (wdt_margin & 0xFC) | 0x83; /* resolution = 4s */ + /* mulitplier = WD_TIMO / 4, resolution = 4s (0x3) */ + wdt |= (wdt_margin & 0xfc) | 0x3; else - /* - * WDS = 1 (0x80), mulitplier = WD_TIMO, resolution = 1s (0x02) - */ - i2c_data[1] = wdt_margin<<2 | 0x82; + /* mulitplier = WD_TIMO, resolution = 1s (0x2) */ + wdt |= wdt_margin << 2 | 0x2; /* * M41T65 has three bits for watchdog resolution. Don't set bit 7, as @@ -541,7 +532,7 @@ static void wdt_ping(void) if (clientdata->features & M41T80_FEATURE_WD) i2c_data[1] &= ~M41T80_WATCHDOG_RB2; - i2c_transfer(save_client->adapter, msgs1, 1); + i2c_smbus_write_byte_data(save_client, M41T80_REG_WATCHDOG, wdt); } /** @@ -551,36 +542,8 @@ static void wdt_ping(void) */ static void wdt_disable(void) { - unsigned char i2c_data[2], i2c_buf[0x10]; - struct i2c_msg msgs0[2] = { - { - .addr = save_client->addr, - .flags = 0, - .len = 1, - .buf = i2c_data, - }, - { - .addr = save_client->addr, - .flags = I2C_M_RD, - .len = 1, - .buf = i2c_buf, - }, - }; - struct i2c_msg msgs1[1] = { - { - .addr = save_client->addr, - .flags = 0, - .len = 2, - .buf = i2c_data, - }, - }; - - i2c_data[0] = 0x09; - i2c_transfer(save_client->adapter, msgs0, 2); - - i2c_data[0] = 0x09; - i2c_data[1] = 0x00; - i2c_transfer(save_client->adapter, msgs1, 1); + i2c_smbus_read_byte_data(save_client, M41T80_REG_WATCHDOG); + i2c_smbus_write_byte_data(save_client, M41T80_REG_WATCHDOG, 0); } /** @@ -782,8 +745,8 @@ static int m41t80_probe(struct i2c_client *client, struct rtc_time tm; struct m41t80_data *clientdata = NULL; - if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C - | I2C_FUNC_SMBUS_BYTE_DATA)) { + if (!i2c_check_functionality(client->adapter, + I2C_FUNC_SMBUS_BYTE_DATA)) { rc = -ENODEV; goto exit; } -- 1.7.3.2