Commit 0a2abbfd authored by Rasmus Villemoes's avatar Rasmus Villemoes Committed by Alexandre Belloni
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rtc: isl12022: drop redundant write to HR register 



There's nothing in the data sheet that says writing to one of the time
keeping registers is necessary to start the RTC. It does so at the
stop condition of the i2c transfer setting the WRTC bit:

  Upon initialization or power-up, the WRTC must be set to "1" to
  enable the RTC. Upon the completion of a valid write (STOP), the RTC
  starts counting.

Moreover, even if such a write to one of the timekeeping registers was
necessary, that's exactly what we do anyway just below when we
actually write the given struct rtc_time to the device.

Signed-off-by: default avatarRasmus Villemoes <linux@rasmusvillemoes.dk>
Link: https://lore.kernel.org/r/20220921114624.3250848-8-linux@rasmusvillemoes.dk


Signed-off-by: default avatarAlexandre Belloni <alexandre.belloni@bootlin.com>
parent 31b108ac

drivers/rtc/rtc-isl12022.c

+0 −14
Original line number Diff line number Diff line
@@ -171,20 +171,6 @@ static int isl12022_rtc_set_time(struct device *dev, struct rtc_time *tm) 
						 buf[0] | ISL12022_INT_WRTC);

			if (ret)

				return ret;



			/* Write to any RTC register to start RTC, we use the

			 * HR register, setting the MIL bit to use the 24 hour

			 * format. */

			ret = isl12022_read_regs(client, ISL12022_REG_HR,

						 buf, 1);

			if (ret)

				return ret;



			ret = isl12022_write_reg(client,

						 ISL12022_REG_HR,

						 buf[0] | ISL12022_HR_MIL);

			if (ret)

				return ret;

		}



		isl12022->write_enabled = true;