m41t80_sqw_set_rate will be called with the result from m41t80_sqw_round_rate, so might as well make m41t80_sqw_set_rate(n) same as m41t80_sqw_set_rate(m41t80_sqw_round_rate(n)) As Russell King wrote[1], "clk_round_rate() is supposed to tell you what you end up with if you ask clk_set_rate() to set the exact same value you passed in - but clk_round_rate() won't modify the hardware." [1] http://lists.infradead.org/pipermail/linux-arm-kernel/2012-January/080175.html Signed-off-by: Troy Kisky <troy.kisky@xxxxxxxxxxxxxxxxxxx> --- drivers/rtc/rtc-m41t80.c | 17 ++++++----------- 1 file changed, 6 insertions(+), 11 deletions(-) diff --git a/drivers/rtc/rtc-m41t80.c b/drivers/rtc/rtc-m41t80.c index 96a606d5f6e6..c90fba3ed861 100644 --- a/drivers/rtc/rtc-m41t80.c +++ b/drivers/rtc/rtc-m41t80.c @@ -490,17 +490,12 @@ static int m41t80_sqw_set_rate(struct clk_hw *hw, unsigned long rate, M41T80_REG_WDAY : M41T80_REG_SQW; int reg, ret, val = 0; - if (rate) { - if (!is_power_of_2(rate)) - return -EINVAL; - val = ilog2(rate); - if (val == ilog2(M41T80_SQW_MAX_FREQ)) - val = 1; - else if (val < (ilog2(M41T80_SQW_MAX_FREQ) - 1)) - val = ilog2(M41T80_SQW_MAX_FREQ) - val; - else - return -EINVAL; - } + if (rate >= M41T80_SQW_MAX_FREQ) + val = 1; + else if (rate >= M41T80_SQW_MAX_FREQ / 4) + val = 2; + else if (rate) + val = 15 - ilog2(rate); reg = i2c_smbus_read_byte_data(client, reg_sqw); if (reg < 0) -- 2.11.0
