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authorTroy Kisky <troy.kisky@boundarydevices.com>2017-11-02 18:58:16 -0700
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2018-01-05 15:48:59 +0100
commit566fb9906ee25a697f4b694dd624398712adf00b (patch)
treeaf7cc9f2c58d0b6595bd521e6bd5d18c9dbde502 /drivers/rtc
parent7623bd95a6dccf74e30a21e437f2f789fbbe27f7 (diff)
rtc: m41t80: remove unneeded checks from m41t80_sqw_set_rate
commit 05a03bf260e0480bfc0db91b1fdbc2115e3f193b upstream. 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@boundarydevices.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> Cc: Christoph Fritz <chf.fritz@googlemail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/rtc')
-rw-r--r--drivers/rtc/rtc-m41t80.c17
1 files 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)