On Wed, Feb 13, 2019 at 06:51:25PM +0100, Uwe Kleine-König wrote:
> Hello Dan,
>
> On Wed, Feb 13, 2019 at 04:17:31PM +0300, Dan Carpenter wrote:
> > The patch 501f98266cad: "rtc: ds1307: rx8130: honor Voltage Loss Flag
> > when reading the time" from Jan 25, 2019, leads to the following
> > static checker warning:
> >
> > drivers/rtc/rtc-ds1307.c:314 ds1307_set_time()
> > warn: this cast is a no-op
> >
> > drivers/rtc/rtc-ds1307.c
> > 304 result = regmap_bulk_write(ds1307->regmap, chip->offset, regs,
> > 305 sizeof(regs));
> > 306 if (result) {
> > 307 dev_err(dev, "%s error %d\n", "write", result);
> > 308 return result;
> > 309 }
> > 310
> > 311 if (ds1307->type == rx_8130) {
> > 312 /* clear Voltage Loss Flag as data is available now */
> > 313 result = regmap_write(ds1307->regmap, RX8130_REG_FLAG,
> > --> 314 ~(u8)RX8130_REG_FLAG_VLF);
> > ^^^^^^^^^^^^^^^^^^^^^^^^
> > RX8130_REG_FLAG_VLF is 0x2. The cast to u8 doesn't change anything
> > because it gets type promoted to int. I don't know what was intended.
>
> This reasoning looks right, yes. I don't remember why I added it.
> Probably because I intended to create the value 0xfd and not 0xfffffffd
> (aka -3).
>
> Feel free to fix this in a patch blaming me.
If it's working as-is then I'm not going to be the one to break it... :P
regards,
dan carpenter
