3.2.81-rc1 review patch. If anyone has any objections, please let me know.
------------------ From: Stephen Boyd <[email protected]> commit eda5ecc0a6b865561997e177c393f0b0136fe3b7 upstream. 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 <[email protected]> Fixes: 92d57a73e410 ("input: Add support for Qualcomm PMIC8XXX power key") Signed-off-by: Stephen Boyd <[email protected]> Tested-by: John Stultz <[email protected]> Acked-by: Bjorn Andersson <[email protected]> Signed-off-by: Dmitry Torokhov <[email protected]> [bwh: Backported to 3.2: use pdata->kpd_trigger_delay_us not kpd_delay] Signed-off-by: Ben Hutchings <[email protected]> --- --- a/drivers/input/misc/pmic8xxx-pwrkey.c +++ b/drivers/input/misc/pmic8xxx-pwrkey.c @@ -98,7 +98,9 @@ static int __devinit pmic8xxx_pwrkey_pro return -EINVAL; } - if (pdata->kpd_trigger_delay_us > 62500) { + /* Valid range of pwr key trigger delay is 1/64 sec to 2 seconds. */ + if (pdata->kpd_trigger_delay_us > USEC_PER_SEC * 2 || + pdata->kpd_trigger_delay_us < USEC_PER_SEC / 64) { dev_err(&pdev->dev, "invalid power key trigger delay\n"); return -EINVAL; } @@ -120,8 +122,8 @@ static int __devinit pmic8xxx_pwrkey_pro pwr->phys = "pmic8xxx_pwrkey/input0"; pwr->dev.parent = &pdev->dev; - delay = (pdata->kpd_trigger_delay_us << 10) / USEC_PER_SEC; - delay = 1 + ilog2(delay); + delay = (pdata->kpd_trigger_delay_us << 6) / USEC_PER_SEC; + delay = ilog2(delay); err = pm8xxx_readb(pdev->dev.parent, PON_CNTL_1, &pon_cntl); if (err < 0) {
