linux-kernel - [PATCH v4 14/19] power: reset: regulator-poweroff: Use devm_register_sys_off_handler(POWER

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Message-ID: <20240212162831.67838-15-afd@ti.com>
Date: Mon, 12 Feb 2024 10:28:26 -0600
From: Andrew Davis <afd@...com>
To: Sebastian Reichel <sre@...nel.org>,
        Manivannan Sadhasivam
	<manivannan.sadhasivam@...aro.org>,
        Cristian Ciocaltea
	<cristian.ciocaltea@...il.com>,
        Florian Fainelli
	<florian.fainelli@...adcom.com>,
        Ray Jui <rjui@...adcom.com>, Scott Branden
	<sbranden@...adcom.com>,
        Bjorn Andersson <andersson@...nel.org>,
        Konrad
 Dybcio <konrad.dybcio@...aro.org>,
        Sean Wang <sean.wang@...iatek.com>,
        Matthias Brugger <matthias.bgg@...il.com>,
        AngeloGioacchino Del Regno
	<angelogioacchino.delregno@...labora.com>
CC: <linux-pm@...r.kernel.org>, <linux-kernel@...r.kernel.org>,
        <linux-actions@...ts.infradead.org>, <linux-arm-msm@...r.kernel.org>,
        <linux-arm-kernel@...ts.infradead.org>,
        <linux-mediatek@...ts.infradead.org>, Andrew Davis <afd@...com>
Subject: [PATCH v4 14/19] power: reset: regulator-poweroff: Use devm_register_sys_off_handler(POWER_OFF)

Use device life-cycle managed register function to simplify probe and
exit paths.

Signed-off-by: Andrew Davis <afd@...com>
---
 drivers/power/reset/regulator-poweroff.c | 36 +++++++++---------------
 1 file changed, 13 insertions(+), 23 deletions(-)

diff --git a/drivers/power/reset/regulator-poweroff.c b/drivers/power/reset/regulator-poweroff.c
index 15160809c423a..fed4978e38580 100644
--- a/drivers/power/reset/regulator-poweroff.c
+++ b/drivers/power/reset/regulator-poweroff.c
@@ -13,18 +13,15 @@
 #include <linux/of.h>
 #include <linux/platform_device.h>
 #include <linux/pm.h>
+#include <linux/reboot.h>
 #include <linux/regulator/consumer.h>
 
 #define TIMEOUT_MS 3000
 
-/*
- * Hold configuration here, cannot be more than one instance of the driver
- * since pm_power_off itself is global.
- */
-static struct regulator *cpu_regulator;
-
-static void regulator_poweroff_do_poweroff(void)
+static int regulator_poweroff_do_poweroff(struct sys_off_data *data)
 {
+	struct regulator *cpu_regulator = data->cb_data;
+
 	if (cpu_regulator && regulator_is_enabled(cpu_regulator))
 		regulator_force_disable(cpu_regulator);
 
@@ -32,30 +29,24 @@ static void regulator_poweroff_do_poweroff(void)
 	mdelay(TIMEOUT_MS);
 
 	WARN_ON(1);
+
+	return NOTIFY_DONE;
 }
 
 static int regulator_poweroff_probe(struct platform_device *pdev)
 {
-	/* If a pm_power_off function has already been added, leave it alone */
-	if (pm_power_off != NULL) {
-		dev_err(&pdev->dev,
-			"%s: pm_power_off function already registered\n",
-			__func__);
-		return -EBUSY;
-	}
+	struct regulator *cpu_regulator;
 
 	cpu_regulator = devm_regulator_get(&pdev->dev, "cpu");
 	if (IS_ERR(cpu_regulator))
 		return PTR_ERR(cpu_regulator);
 
-	pm_power_off = &regulator_poweroff_do_poweroff;
-	return 0;
-}
-
-static void regulator_poweroff_remove(struct platform_device *pdev)
-{
-	if (pm_power_off == &regulator_poweroff_do_poweroff)
-		pm_power_off = NULL;
+	/* Set this handler to low priority to not override an existing handler */
+	return devm_register_sys_off_handler(&pdev->dev,
+					     SYS_OFF_MODE_POWER_OFF,
+					     SYS_OFF_PRIO_LOW,
+					     regulator_poweroff_do_poweroff,
+					     cpu_regulator);
 }
 
 static const struct of_device_id of_regulator_poweroff_match[] = {
@@ -66,7 +57,6 @@ MODULE_DEVICE_TABLE(of, of_regulator_poweroff_match);
 
 static struct platform_driver regulator_poweroff_driver = {
 	.probe = regulator_poweroff_probe,
-	.remove_new = regulator_poweroff_remove,
 	.driver = {
 		.name = "poweroff-regulator",
 		.of_match_table = of_regulator_poweroff_match,
-- 
2.39.2