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.
Best regards
Uwe
--
Pengutronix e.K. | Uwe Kleine-König |
Industrial Linux Solutions | http://www.pengutronix.de/ |
