rtc: zynqmp: correct frequency value

Fix calibration value in case a clock reference is provided.
The actual calibration value written into register is
frequency - 1.

Reviewed-by: Harini T <harini.t@amd.com>
Tested-by: Harini T <harini.t@amd.com>
Signed-off-by: Tomas Melin <tomas.melin@vaisala.com>
Acked-by: Michal Simek <michal.simek@amd.com>
Link: https://patch.msgid.link/20260122-zynqmp-rtc-updates-v4-1-d4edb966b499@vaisala.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

diff --git a/drivers/rtc/rtc-zynqmp.c b/drivers/rtc/rtc-zynqmp.c
index 3baa2b481d9f2008750046005283b98a0d546c5c..856bc1678e7d31144f320ae9f75fc58c742a2a64 100644 (file)
--- a/drivers/rtc/rtc-zynqmp.c
+++ b/drivers/rtc/rtc-zynqmp.c
@@ -345,7 +345,10 @@ static int xlnx_rtc_probe(struct platform_device *pdev)
                                           &xrtcdev->freq);
                if (ret)
                        xrtcdev->freq = RTC_CALIB_DEF;
+       } else {
+               xrtcdev->freq--;
        }
+
        ret = readl(xrtcdev->reg_base + RTC_CALIB_RD);
        if (!ret)
                writel(xrtcdev->freq, (xrtcdev->reg_base + RTC_CALIB_WR));