linux-kernel - [PATCH] mfd: cs42l43: Use gpiod_set

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Message-ID: <20241112111230.580086-1-ckeepax@opensource.cirrus.com>
Date: Tue, 12 Nov 2024 11:12:30 +0000
From: Charles Keepax <ckeepax@...nsource.cirrus.com>
To: <lee@...nel.org>
CC: <patches@...nsource.cirrus.com>, <linux-kernel@...r.kernel.org>
Subject: [PATCH] mfd: cs42l43: Use gpiod_set_raw for GPIO operations

The GPIO framework supports specifying if a GPIO is active low or
high and will invert accordingly. Whilst specifying this is part of
the normal GPIO definition flow on device tree systems, it is a DSD
extension under ACPI, that Windows doesn't really use. This means most
ACPI systems do not set the polarity of the pin.

The current cs42l43 driver assumes it is setting the level of the line
directly, which is actually the case on all current systems and likely
most future ones. However if the part was used in a device tree system
or an ACPI system that actually used the DSD extensions this would get
inverted, causing the driver to fail probe. As the driver always knows
the polarity of its own reset line, use the raw set API making the
intention to set the level directly clear and to avoid any such future
issues.

Signed-off-by: Charles Keepax <ckeepax@...nsource.cirrus.com>
---
 drivers/mfd/cs42l43.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/mfd/cs42l43.c b/drivers/mfd/cs42l43.c
index e5f17fc430e48..60e53b7903d5d 100644
--- a/drivers/mfd/cs42l43.c
+++ b/drivers/mfd/cs42l43.c
@@ -982,7 +982,7 @@ static int cs42l43_power_up(struct cs42l43 *cs42l43)
 	/* vdd-p must be on for 50uS before any other supply */
 	usleep_range(CS42L43_VDDP_DELAY_US, 2 * CS42L43_VDDP_DELAY_US);
 
-	gpiod_set_value_cansleep(cs42l43->reset, 1);
+	gpiod_set_raw_value_cansleep(cs42l43->reset, 1);
 
 	ret = regulator_bulk_enable(CS42L43_N_SUPPLIES, cs42l43->core_supplies);
 	if (ret) {
@@ -1003,7 +1003,7 @@ static int cs42l43_power_up(struct cs42l43 *cs42l43)
 err_core_supplies:
 	regulator_bulk_disable(CS42L43_N_SUPPLIES, cs42l43->core_supplies);
 err_reset:
-	gpiod_set_value_cansleep(cs42l43->reset, 0);
+	gpiod_set_raw_value_cansleep(cs42l43->reset, 0);
 	regulator_disable(cs42l43->vdd_p);
 
 	return ret;
@@ -1025,7 +1025,7 @@ static int cs42l43_power_down(struct cs42l43 *cs42l43)
 		return ret;
 	}
 
-	gpiod_set_value_cansleep(cs42l43->reset, 0);
+	gpiod_set_raw_value_cansleep(cs42l43->reset, 0);
 
 	ret = regulator_disable(cs42l43->vdd_p);
 	if (ret) {
@@ -1050,11 +1050,13 @@ int cs42l43_dev_probe(struct cs42l43 *cs42l43)
 
 	regcache_cache_only(cs42l43->regmap, true);
 
-	cs42l43->reset = devm_gpiod_get_optional(cs42l43->dev, "reset", GPIOD_OUT_LOW);
+	cs42l43->reset = devm_gpiod_get_optional(cs42l43->dev, "reset", GPIOD_OUT_HIGH);
 	if (IS_ERR(cs42l43->reset))
 		return dev_err_probe(cs42l43->dev, PTR_ERR(cs42l43->reset),
 				     "Failed to get reset\n");
 
+	gpiod_set_raw_value_cansleep(cs42l43->reset, 0);
+
 	cs42l43->vdd_p = devm_regulator_get(cs42l43->dev, "vdd-p");
 	if (IS_ERR(cs42l43->vdd_p))
 		return dev_err_probe(cs42l43->dev, PTR_ERR(cs42l43->vdd_p),
-- 
2.39.5