linux-kernel - [PATCH v2] leds/pca963x: implement power management

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Date: Mon, 29 Jan 2024 16:45:05 +0530
From: Amitesh Singh <singh.amitesh@...il.com>
To: pavel@....cz,
	lee@...nel.org,
	linux-leds@...r.kernel.org,
	linux-kernel@...r.kernel.org
Cc: Amitesh Singh <singh.amitesh@...il.com>
Subject: [PATCH v2] leds/pca963x: implement power management

This implements power management for pca9633
which enables device sleep and resume on system-wide
sleep/hibernation

Signed-off-by: Amitesh Singh <singh.amitesh@...il.com>
---
 drivers/leds/leds-pca963x.c | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/drivers/leds/leds-pca963x.c b/drivers/leds/leds-pca963x.c
index 47223c850e4b..227f24ba2ca2 100644
--- a/drivers/leds/leds-pca963x.c
+++ b/drivers/leds/leds-pca963x.c
@@ -39,6 +39,7 @@
 #define PCA963X_LED_PWM		0x2	/* Controlled through PWM */
 #define PCA963X_LED_GRP_PWM	0x3	/* Controlled through PWM/GRPPWM */
 
+#define PCA963X_MODE1_SLEEP     0x04    /* Normal mode or Low Power mode, oscillator off */
 #define PCA963X_MODE2_OUTDRV	0x04	/* Open-drain or totem pole */
 #define PCA963X_MODE2_INVRT	0x10	/* Normal or inverted direction */
 #define PCA963X_MODE2_DMBLNK	0x20	/* Enable blinking */
@@ -380,6 +381,34 @@ static int pca963x_register_leds(struct i2c_client *client,
 	return ret;
 }
 
+#ifdef CONFIG_PM_SLEEP
+static int pca963x_suspend(struct device *dev)
+{
+	struct pca963x *chip = dev_get_drvdata(dev);
+	u8 reg;
+
+	reg = i2c_smbus_read_byte_data(chip->client, PCA963X_MODE1);
+	reg = reg | BIT(PCA963X_MODE1_SLEEP);
+	i2c_smbus_write_byte_data(chip->client, PCA963X_MODE1, reg);
+
+	return 0;
+}
+
+static int pca963x_resume(struct device *dev)
+{
+	struct pca963x *chip = dev_get_drvdata(dev);
+	u8 reg;
+
+	reg = i2c_smbus_read_byte_data(chip->client, PCA963X_MODE1);
+	reg = reg & ~BIT(PCA963X_MODE1_SLEEP);
+	i2c_smbus_write_byte_data(chip->client, PCA963X_MODE1, reg);
+
+	return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(pca963x_pm, pca963x_suspend, pca963x_resume);
+
 static const struct of_device_id of_pca963x_match[] = {
 	{ .compatible = "nxp,pca9632", },
 	{ .compatible = "nxp,pca9633", },
@@ -430,6 +459,7 @@ static struct i2c_driver pca963x_driver = {
 	.driver = {
 		.name	= "leds-pca963x",
 		.of_match_table = of_pca963x_match,
+		.pm = &pca963x_pm
 	},
 	.probe = pca963x_probe,
 	.id_table = pca963x_id,
-- 
2.43.0