On Mon, Feb 15, 2016 at 9:38 PM, Arnd Bergmann <[email protected]> wrote: > On Monday 15 February 2016 21:56:42 Viresh Kumar wrote: >> We are currently required to do two checks for regulator pointer: >> IS_ERR() and IS_NULL(). >> >> And multiple instances are reported, about both of these not being used >> consistently and so resulting in crashes. >> >> Fix that by initializing regulator pointer with an error value and >> checking it only against an error. >> >> This makes code consistent and efficient. > > There is usually something else wrong if you have to check for both. > Why exactly do you need to check for both IS_ERR and NULL? > >> diff --git a/drivers/base/power/opp/core.c b/drivers/base/power/opp/core.c >> index d7cd4e265766..146b6197d598 100644 >> --- a/drivers/base/power/opp/core.c >> +++ b/drivers/base/power/opp/core.c >> @@ -257,7 +257,7 @@ unsigned long dev_pm_opp_get_max_volt_latency(struct >> device *dev) >> } >> >> reg = dev_opp->regulator; >> - if (IS_ERR_OR_NULL(reg)) { >> + if (IS_ERR(reg)) { >> /* Regulator may not be required for device */ >> if (reg) >> dev_err(dev, "%s: Invalid regulator (%ld)\n", __func__, >> @@ -798,6 +798,9 @@ static struct device_opp *_add_device_opp(struct device >> *dev) >> of_node_put(np); >> } >> >> + /* Set regulator to a non-NULL error value */ >> + dev_opp->regulator = ERR_PTR(-EFAULT); >> + >> /* Find clk for the device */ >> dev_opp->clk = clk_get(dev, NULL); >> if (IS_ERR(dev_opp->clk)) { > > -EFAULT has a very specific meaning (accessing an invalid pointer from > user space), I don't think you want that one.
Yeah, agreed. That should be something like -ENXIO IMO. Thanks, Rafael
