Convert goto to a loop and set a hard upper limit on the number of times driver would try to make RTC work (as opposed to having an infinite retry loop).
Signed-off-by: Andrey Smirnov <[email protected]> --- drivers/rtc/rtc-ds1307.c | 151 +++++++++++++++++++++++++---------------------- 1 file changed, 82 insertions(+), 69 deletions(-) diff --git a/drivers/rtc/rtc-ds1307.c b/drivers/rtc/rtc-ds1307.c index 67907f1..cbbe9f0 100644 --- a/drivers/rtc/rtc-ds1307.c +++ b/drivers/rtc/rtc-ds1307.c @@ -1424,87 +1424,100 @@ static int ds1307_chip_configure(const struct ds1307 *ds1307) static int ds1307_chip_sanity_check(const struct ds1307 *ds1307) { - int tmp; + int tmp, retries; u8 regs[DS1307_REG_COUNT]; struct i2c_client *client = ds1307->client; -read_rtc: - /* read RTC registers */ - tmp = ds1307->read_block_data(ds1307->client, ds1307->offset, 8, regs); - if (tmp != 8) { - dev_dbg(&client->dev, "read error %d\n", tmp); - return -EIO; - } - - /* - * minimal sanity checking; some chips (like DS1340) don't - * specify the extra bits as must-be-zero, but there are - * still a few values that are clearly out-of-range. - */ - tmp = regs[DS1307_REG_SECS]; - switch (ds1307->type) { - case ds_1307: - case m41t00: - /* clock halted? turn it on, so clock can tick. */ - if (tmp & DS1307_BIT_CH) { - i2c_smbus_write_byte_data(client, DS1307_REG_SECS, 0); - dev_warn(&client->dev, "SET TIME!\n"); - goto read_rtc; - } - break; - case ds_1338: - /* clock halted? turn it on, so clock can tick. */ - if (tmp & DS1307_BIT_CH) - i2c_smbus_write_byte_data(client, DS1307_REG_SECS, 0); - - /* oscillator fault? clear flag, and warn */ - if (regs[DS1307_REG_CONTROL] & DS1338_BIT_OSF) { - i2c_smbus_write_byte_data(client, DS1307_REG_CONTROL, - regs[DS1307_REG_CONTROL] - & ~DS1338_BIT_OSF); - dev_warn(&client->dev, "SET TIME!\n"); - goto read_rtc; - } - break; - case ds_1340: - /* clock halted? turn it on, so clock can tick. */ - if (tmp & DS1340_BIT_nEOSC) - i2c_smbus_write_byte_data(client, DS1307_REG_SECS, 0); - - tmp = i2c_smbus_read_byte_data(client, DS1340_REG_FLAG); - if (tmp < 0) { + for (retries = 0; retries < 5; retries++) { + /* read RTC registers */ + tmp = ds1307->read_block_data(ds1307->client, + ds1307->offset, 8, regs); + if (tmp != 8) { dev_dbg(&client->dev, "read error %d\n", tmp); return -EIO; } - /* oscillator fault? clear flag, and warn */ - if (tmp & DS1340_BIT_OSF) { - i2c_smbus_write_byte_data(client, DS1340_REG_FLAG, 0); - dev_warn(&client->dev, "SET TIME!\n"); - } - break; - case mcp794xx: - /* make sure that the backup battery is enabled */ - if (!(regs[DS1307_REG_WDAY] & MCP794XX_BIT_VBATEN)) { - i2c_smbus_write_byte_data(client, DS1307_REG_WDAY, - regs[DS1307_REG_WDAY] - | MCP794XX_BIT_VBATEN); - } + /* + * minimal sanity checking; some chips (like DS1340) + * don't specify the extra bits as must-be-zero, but + * there are still a few values that are clearly + * out-of-range. + */ + tmp = regs[DS1307_REG_SECS]; + switch (ds1307->type) { + case ds_1307: + case m41t00: + /* clock halted? turn it on, so clock can tick. */ + if (tmp & DS1307_BIT_CH) { + i2c_smbus_write_byte_data(client, + DS1307_REG_SECS, 0); + dev_warn(&client->dev, "SET TIME!\n"); + continue; + } + break; + case ds_1338: + /* clock halted? turn it on, so clock can tick. */ + if (tmp & DS1307_BIT_CH) + i2c_smbus_write_byte_data(client, + DS1307_REG_SECS, 0); + + /* oscillator fault? clear flag, and warn */ + if (regs[DS1307_REG_CONTROL] & DS1338_BIT_OSF) { + i2c_smbus_write_byte_data(client, + DS1307_REG_CONTROL, + regs[DS1307_REG_CONTROL] + & ~DS1338_BIT_OSF); + dev_warn(&client->dev, "SET TIME!\n"); + continue; + } + break; + case ds_1340: + /* clock halted? turn it on, so clock can tick. */ + if (tmp & DS1340_BIT_nEOSC) + i2c_smbus_write_byte_data(client, + DS1307_REG_SECS, 0); + + tmp = i2c_smbus_read_byte_data(client, DS1340_REG_FLAG); + if (tmp < 0) { + dev_dbg(&client->dev, "read error %d\n", tmp); + return -EIO; + } + + /* oscillator fault? clear flag, and warn */ + if (tmp & DS1340_BIT_OSF) { + i2c_smbus_write_byte_data(client, + DS1340_REG_FLAG, 0); + dev_warn(&client->dev, "SET TIME!\n"); + } + return 0; - /* clock halted? turn it on, so clock can tick. */ - if (!(tmp & MCP794XX_BIT_ST)) { - i2c_smbus_write_byte_data(client, DS1307_REG_SECS, - MCP794XX_BIT_ST); - dev_warn(&client->dev, "SET TIME!\n"); - goto read_rtc; + case mcp794xx: + /* make sure that the backup battery is enabled */ + if (!(regs[DS1307_REG_WDAY] & MCP794XX_BIT_VBATEN)) { + i2c_smbus_write_byte_data(client, + DS1307_REG_WDAY, + regs[DS1307_REG_WDAY] + | MCP794XX_BIT_VBATEN); + } + + /* clock halted? turn it on, so clock can tick. */ + if (!(tmp & MCP794XX_BIT_ST)) { + i2c_smbus_write_byte_data(client, + DS1307_REG_SECS, + MCP794XX_BIT_ST); + dev_warn(&client->dev, "SET TIME!\n"); + continue; + } + + break; + default: + break; } - break; - default: - break; + return 0; } - return 0; + return -EIO; } static int ds1307_probe(struct i2c_client *client, -- 2.5.5
