diff options
author | Stephen Boyd <sboyd@codeaurora.org> | 2016-04-17 15:21:42 +0300 |
---|---|---|
committer | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2016-04-17 15:24:53 +0300 |
commit | eda5ecc0a6b865561997e177c393f0b0136fe3b7 (patch) | |
tree | 3d19c74c486fe015b0ebbbf6bdb6dc674ef84c0b /drivers/input/misc/pmic8xxx-pwrkey.c | |
parent | ca3704c23a3b3dfc9d721cf21953fd6b3cbfc3e0 (diff) | |
download | linux-eda5ecc0a6b865561997e177c393f0b0136fe3b7.tar.xz |
Input: pmic8xxx-pwrkey - fix algorithm for converting trigger delay
The trigger delay algorithm that converts from microseconds to
the register value looks incorrect. According to most of the PMIC
documentation, the equation is
delay (Seconds) = (1 / 1024) * 2 ^ (x + 4)
except for one case where the documentation looks to have a
formatting issue and the equation looks like
delay (Seconds) = (1 / 1024) * 2 x + 4
Most likely this driver was written with the improper
documentation to begin with. According to the downstream sources
the valid delays are from 2 seconds to 1/64 second, and the
latter equation just doesn't make sense for that. Let's fix the
algorithm and the range check to match the documentation and the
downstream sources.
Reported-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Fixes: 92d57a73e410 ("input: Add support for Qualcomm PMIC8XXX power key")
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Tested-by: John Stultz <john.stultz@linaro.org>
Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Diffstat (limited to 'drivers/input/misc/pmic8xxx-pwrkey.c')
-rw-r--r-- | drivers/input/misc/pmic8xxx-pwrkey.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/drivers/input/misc/pmic8xxx-pwrkey.c b/drivers/input/misc/pmic8xxx-pwrkey.c index 3f02e0e03d12..67aab86048ad 100644 --- a/drivers/input/misc/pmic8xxx-pwrkey.c +++ b/drivers/input/misc/pmic8xxx-pwrkey.c @@ -353,7 +353,8 @@ static int pmic8xxx_pwrkey_probe(struct platform_device *pdev) if (of_property_read_u32(pdev->dev.of_node, "debounce", &kpd_delay)) kpd_delay = 15625; - if (kpd_delay > 62500 || kpd_delay == 0) { + /* Valid range of pwr key trigger delay is 1/64 sec to 2 seconds. */ + if (kpd_delay > USEC_PER_SEC * 2 || kpd_delay < USEC_PER_SEC / 64) { dev_err(&pdev->dev, "invalid power key trigger delay\n"); return -EINVAL; } @@ -385,8 +386,8 @@ static int pmic8xxx_pwrkey_probe(struct platform_device *pdev) pwr->name = "pmic8xxx_pwrkey"; pwr->phys = "pmic8xxx_pwrkey/input0"; - delay = (kpd_delay << 10) / USEC_PER_SEC; - delay = 1 + ilog2(delay); + delay = (kpd_delay << 6) / USEC_PER_SEC; + delay = ilog2(delay); err = regmap_read(regmap, PON_CNTL_1, &pon_cntl); if (err < 0) { |