linux-kernel - [PATCH v3 09/14] rtc: pcf2127: set PWRMNG value for PCF2131

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Date:   Thu, 15 Dec 2022 10:02:10 -0500
From:   Hugo Villeneuve <hugo@...ovil.com>
To:     a.zummo@...ertech.it, alexandre.belloni@...tlin.com,
        robh+dt@...nel.org, krzysztof.kozlowski+dt@...aro.org
Cc:     linux-rtc@...r.kernel.org, devicetree@...r.kernel.org,
        linux-kernel@...r.kernel.org, hugo@...ovil.com,
        Hugo Villeneuve <hvilleneuve@...onoff.com>
Subject: [PATCH v3 09/14] rtc: pcf2127: set PWRMNG value for PCF2131

From: Hugo Villeneuve <hvilleneuve@...onoff.com>

Default PWRMNG[2:0] bits are set to 000b for PCF2127/29, but to
111b for PCF2131.

Set these bits to 000b to select same mode as PCF2127/29.

Signed-off-by: Hugo Villeneuve <hvilleneuve@...onoff.com>
---
 drivers/rtc/rtc-pcf2127.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/drivers/rtc/rtc-pcf2127.c b/drivers/rtc/rtc-pcf2127.c
index 68af4d0438b8..241189ee4a05 100644
--- a/drivers/rtc/rtc-pcf2127.c
+++ b/drivers/rtc/rtc-pcf2127.c
@@ -53,6 +53,7 @@
 #define PCF2127_BIT_CTRL3_BLF			BIT(2)
 #define PCF2127_BIT_CTRL3_BF			BIT(3)
 #define PCF2127_BIT_CTRL3_BTSE			BIT(4)
+#define PCF2127_CTRL3_PWRMNG_MASK		GENMASK(7, 5)
 /* Control register 4 */
 #define PCF2131_REG_CTRL4		0x03
 #define PCF2131_BIT_CTRL4_TSF4			BIT(4)
@@ -1129,6 +1130,20 @@ static int pcf2127_probe(struct device *dev, struct regmap *regmap,
 	regmap_clear_bits(pcf2127->regmap, PCF2127_REG_CTRL1,
 				PCF2127_BIT_CTRL1_POR_OVRD);
 
+	/* Make sure PWRMNG[2:0] is set to 000b. This is the default for
+	 * PCF2127/29, but not for PCF2131 (default of 111b).
+	 *
+	 * PWRMNG[2:0]  = 000b:
+	 *   battery switch-over function is enabled in standard mode;
+	 *   battery low detection function is enabled
+	 */
+	ret = regmap_clear_bits(pcf2127->regmap, PCF2127_REG_CTRL3,
+				PCF2127_CTRL3_PWRMNG_MASK);
+	if (ret < 0) {
+		dev_err(dev, "PWRMNG config failed\n");
+		return ret;
+	}
+
 	ret = regmap_read(pcf2127->regmap, pcf2127->cfg->reg_clkout, &val);
 	if (ret < 0)
 		return ret;
-- 
2.30.2