[PATCH 15/15] power: supply: ab8500_fg: Avoid reserved AB8505 CCConf bit

[Linus Walleij <linusw@kernel.org>]

AB8500 defines CCConf bit 1 as CCDeepSleepEna, but AB8505 reserves
bits 7:1 and only defines bit 0, CCPwrUpEna. The fuel-gauge driver
currently writes both bits whenever it starts the coulomb counter.

The Samsung-GT-S7710-Skomer and related Samsung product trees use the
same unconditional value in their fuel-gauge drivers, so they provide
no AB8505 workaround to carry over. Select the value from the detected
PMIC variant instead, retaining the deep-sleep enable bit on all
existing non-AB8505 paths and avoiding the reserved bit on AB8505.

Fixes: a982362c1723 ("mfd: Support for the AB8500 AB8505 variant")
Assisted-by: LLM
Signed-off-by: Linus Walleij <linusw@kernel.org>
---
 drivers/power/supply/ab8500_fg.c | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/power/supply/ab8500_fg.c b/drivers/power/supply/ab8500_fg.c
index b3f29a43745d..069e7fee1d16 100644
--- a/drivers/power/supply/ab8500_fg.c
+++ b/drivers/power/supply/ab8500_fg.c
@@ -451,6 +451,16 @@ static void ab8500_fg_fill_cap_sample(struct ab8500_fg *di, int sample)
 	avg->avg = sample;
 }
 
+static u8 ab8500_fg_cc_config(struct ab8500_fg *di)
+{
+	u8 config = CC_PWR_UP_ENA;
+
+	if (!is_ab8505(di->parent))
+		config |= CC_DEEP_SLEEP_ENA;
+
+	return config;
+}
+
 /**
  * ab8500_fg_coulomb_counter() - enable coulomb counter
  * @di:		pointer to the ab8500_fg structure
@@ -481,7 +491,7 @@ static int ab8500_fg_coulomb_counter(struct ab8500_fg *di, bool enable)
 		/* Start the CC */
 		ret = abx500_set_register_interruptible(di->dev, AB8500_RTC,
 			AB8500_RTC_CC_CONF_REG,
-			(CC_DEEP_SLEEP_ENA | CC_PWR_UP_ENA));
+			ab8500_fg_cc_config(di));
 		if (ret)
 			goto cc_err;
 
@@ -555,7 +565,7 @@ int ab8500_fg_inst_curr_start(struct ab8500_fg *di)
 		/* Start the CC */
 		ret = abx500_set_register_interruptible(di->dev, AB8500_RTC,
 			AB8500_RTC_CC_CONF_REG,
-			(CC_DEEP_SLEEP_ENA | CC_PWR_UP_ENA));
+			ab8500_fg_cc_config(di));
 		if (ret)
 			goto fail;
 	} else {

-- 
2.55.0