On Wed, Jun 24, 2020 at 10:37 PM, Uwe Kleine-König wrote:
> On Wed, Jun 24, 2020 at 12:04:24PM +0900, Roy Im wrote:
> > Hello Uwe,
> >
> > On Tue, June 23, 2020 11:41 PM, Uwe Kleine-König wrote:
> > >
> > > Hello,
> > >
> > > On Mon, Jun 15, 2020 at 08:40:23PM +0900, Roy Im wrote:
> > > > Adds support for the Dialog DA7280 LRA/ERM Haptic Driver with
> > > > multiple mode and integrated waveform memory and wideband support.
> > > > It communicates via an I2C bus to the device.
> > > >
> > > > Signed-off-by: Roy Im <roy.im.opensource@xxxxxxxxxxx>
> > > >
> > > > + period2freq = 1000000 / state.period;
> > > > + if (period2freq < DA7280_MIN_PWM_FREQ_KHZ ||
> > > > + period2freq > DA7280_MAX_PWM_FREQ_KHZ) {
> > > > + dev_err(dev, "Not supported PWM frequency(%d)\n",
> > > > + period2freq);
> > >
> > > Doesn't the compiler warn here about period2freq being unsigned and %d being for signed int values?
> > >
> > > For my (non-native) English ear s/Not supported/Unsupported/ sounds
> > > better. Also my eyes would be pleases by a space before the opening brace.
> >
> > I didn't see any warning message, but I will change/improve them to proper one and the log as below.
> >
> > period2freq = 1000000 / state.period;
> > if (period2freq < DA7280_MIN_PWM_FREQ_KHZ ||
> > period2freq > DA7280_MAX_PWM_FREQ_KHZ) {
> > dev_err(dev, "Unsupported PWM frequency (%u)\n",
> > period2freq);
> > return -EINVAL;
> > }
> > If you look ok, let me update this so.
>
> looks fine.
>
> Note that you don't need the division if you check for:
>
> if (state.period > 100000 || state.period < 4000) {
> ...
>
> (maybe the compiler is already clever enough to get rid of the division for you, but then the check is:
>
> if (state.period > 100000 || state.period < 3985) {
>
> because of rounding errors.)
OK, you are right, that will be better. So let me change that as below if you look fine.
/* Check PWM period, PWM freq = 1000000 / state.period.
* The valid PWM freq range: 10k ~ 250kHz.
*/
if (state.period > 100000 || state.period < 3985) {
dev_err(dev, "Unsupported PWM period (%u)\n",
state.period);
return -EINVAL;
}
>
> Best regards
> Uwe
>
> --
> Pengutronix e.K. | Uwe Kleine-König |
> Industrial Linux Solutions | https://www.pengutronix.de/ |
