arm64: tegra: Add pwm-fan profile settings

-----Original Message-----
From: Sandipan Patra <[email protected]>
Sent: Friday, April 17, 2020 7:03 PM
To: Thierry Reding <[email protected]>; [email protected]; u.kleine- [email protected]; Jonathan Hunter <[email protected]>
Cc: Bibek Basu <[email protected]>; Bitan Biswas <[email protected]>; [email protected]; [email protected]; linux- [email protected]; [email protected]; Sandipan Patra <[email protected]>
Subject: [PATCH 2/2] hwmon: pwm-fan: Add profile support and add remove
module support

This change has 2 parts:
1. Add support for profiles mode settings.
This allows different fan settings for trip point temp/hyst/pwm. T194 has multiple fan-profiles support.

2. Add pwm-fan remove support. This is essential since the config is tristate capable.

Signed-off-by Sandipan Patra <[email protected]>

---
 drivers/hwmon/pwm-fan.c | 113
+++++++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 101 insertions(+), 12 deletions(-)

drivers/hwmon/pwm-fan.c index renamed from drivers/hwmon/pwm-fan.c +0 -0

30b7b3e..6332ed8 100644

drivers/hwmon/pwm-fan.c +78 -12

@@ -3,8 +3,10 @@
  * pwm-fan.c - Hwmon driver for fans connected to PWM lines.
  *
  * Copyright (c) 2014 Samsung Electronics Co., Ltd.
+ * Copyright (c) 2020, NVIDIA Corporation.
  *
  * Author: Kamil Debski <[email protected]>
+ * Author: Sandipan Patra <[email protected]>
  */
 
 #include <linux/hwmon.h>

@@ -21,6 +23,8 @@
 #include <linux/timer.h>
 
 #define MAX_PWM 255
+/* Based on OF max device tree node name length */
+#define MAX_PROFILE_NAME_LENGTH	31
 
 struct pwm_fan_ctx {
 	struct mutex lock;

@@ -38,6 +42,12 @@ struct pwm_fan_ctx {
 	unsigned int pwm_fan_state;
 	unsigned int pwm_fan_max_state;
 	unsigned int *pwm_fan_cooling_levels;
+
+	unsigned int pwm_fan_profiles;
+	const char **fan_profile_names;
+	unsigned int **fan_profile_cooling_levels;
+	unsigned int fan_current_profile;
+
 	struct thermal_cooling_device *cdev;
 };
 

@@ -227,28 +237,86 @@ static int pwm_fan_of_get_cooling_data(struct
 device *dev,
 				       struct pwm_fan_ctx *ctx)
 {
 	struct device_node *np = dev->of_node;
+	struct device_node *base_profile = NULL;
+	struct device_node *profile_np = NULL;
+	const char *default_profile = NULL;
 	int num, i, ret;
 
-	if (!of_find_property(np, "cooling-levels", NULL))
-		return 0;
+	num = of_property_count_u32_elems(np, "cooling-levels");
+	if (num <= 0) {
+		base_profile = of_get_child_by_name(np, "profiles");
+		if (!base_profile) {
+			dev_err(dev, "Wrong Data\n");
+			return -EINVAL;
+		}
+	}
+
+	if (base_profile) {
+		ctx->pwm_fan_profiles =
+			of_get_available_child_count(base_profile);
+
+		if (ctx->pwm_fan_profiles <= 0) {
+			dev_err(dev, "Profiles used but not defined\n");
+			return -EINVAL;
+		}
 
-	ret = of_property_count_u32_elems(np, "cooling-levels");
-	if (ret <= 0) {
-		dev_err(dev, "Wrong data!\n");
-		return ret ? : -EINVAL;
+		ctx->fan_profile_names = devm_kzalloc(dev,
+			sizeof(const char *) * ctx->pwm_fan_profiles,
+							GFP_KERNEL);
+		ctx->fan_profile_cooling_levels = devm_kzalloc(dev,
+			sizeof(int *) * ctx->pwm_fan_profiles,
+							GFP_KERNEL);
+
+		if (!ctx->fan_profile_names
+				|| !ctx->fan_profile_cooling_levels)
+			return -ENOMEM;
+
+		ctx->fan_current_profile = 0;
+		i = 0;
+		for_each_available_child_of_node(base_profile, profile_np) {
+			num = of_property_count_u32_elems(profile_np,
+							"cooling-levels");
+			if (num <= 0) {
+				dev_err(dev, "No data in cooling-levels inside
 profile node!\n");
+				return -EINVAL;
+			}
+
+			of_property_read_string(profile_np, "name",
+						&ctx->fan_profile_names[i]);
+			if (default_profile &&
+				!strncmp(default_profile,
+				ctx->fan_profile_names[i],
+				MAX_PROFILE_NAME_LENGTH))
+				ctx->fan_current_profile = i;
+
+			ctx->fan_profile_cooling_levels[i] =
+				devm_kzalloc(dev, sizeof(int) * num,
+							GFP_KERNEL);
+			if (!ctx->fan_profile_cooling_levels[i])
+				return -ENOMEM;
+
+			of_property_read_u32_array(profile_np, "cooling-
 levels",
+				ctx->fan_profile_cooling_levels[i], num);
+			i++;
+		}
 	}
 
-	num = ret;
 	ctx->pwm_fan_cooling_levels = devm_kcalloc(dev, num, sizeof(u32),
 						   GFP_KERNEL);
 	if (!ctx->pwm_fan_cooling_levels)
 		return -ENOMEM;
 
-	ret = of_property_read_u32_array(np, "cooling-levels",
-					 ctx->pwm_fan_cooling_levels, num);
-	if (ret) {
-		dev_err(dev, "Property 'cooling-levels' cannot be read!\n");
-		return ret;
+	if (base_profile) {
+		memcpy(ctx->pwm_fan_cooling_levels,
+		  ctx->fan_profile_cooling_levels[ctx->fan_current_profile],
+						num);
+	} else {
+		ret = of_property_read_u32_array(np, "cooling-levels",
+				ctx->pwm_fan_cooling_levels, num);
+		if (ret) {
+			dev_err(dev, "Property 'cooling-levels' cannot be

read!\n");

drivers/hwmon/pwm-fan.c +20 -0

+			return -EINVAL;
+		}
 	}
 
 	for (i = 0; i < num; i++) {

@@ -390,6 +458,25 @@ static int pwm_fan_probe(struct platform_device
 *pdev)
 	return 0;
 }
 
+static int pwm_fan_remove(struct platform_device *pdev) {
+	struct pwm_fan_ctx *ctx = platform_get_drvdata(pdev);
+	struct pwm_args args;
+
+	if (!ctx)
+		return -EINVAL;
+
+	if (IS_ENABLED(CONFIG_THERMAL))
+		thermal_cooling_device_unregister(ctx->cdev);
+
+	pwm_get_args(ctx->pwm, &args);
+	pwm_config(ctx->pwm, 0, args.period);
+	pwm_disable(ctx->pwm);
+
+	return 0;
+}
+
+
 static int pwm_fan_disable(struct device *dev)  {
 	struct pwm_fan_ctx *ctx = dev_get_drvdata(dev); @@ -465,6 +552,7

@@ MODULE_DEVICE_TABLE(of, of_pwm_fan_match);

static struct platform_driver pwm_fan_driver = {

drivers/hwmon/pwm-fan.c +2 -1

 	.probe		= pwm_fan_probe,
+	.remove         = pwm_fan_remove,
 	.shutdown	= pwm_fan_shutdown,
 	.driver	= {
 		.name		= "pwm-fan",

@@ -476,6 +564,7 @@ static struct platform_driver pwm_fan_driver = {
 module_platform_driver(pwm_fan_driver);
 
 MODULE_AUTHOR("Kamil Debski <[email protected]>");
+MODULE_AUTHOR("Sandipan Patra <[email protected]>");
 MODULE_ALIAS("platform:pwm-fan");
 MODULE_DESCRIPTION("PWM FAN driver");
 MODULE_LICENSE("GPL");
--

2.7.4

-----Original Message-----
From: Sandipan Patra <[email protected]>
Sent: Friday, April 17, 2020 7:03 PM
To: Thierry Reding <[email protected]>; [email protected]; u.kleine- [email protected]; Jonathan Hunter <[email protected]>
Cc: Bibek Basu <[email protected]>; Bitan Biswas <[email protected]>; [email protected]; [email protected]; linux- [email protected]; [email protected]; Sandipan Patra <[email protected]>
Subject: [PATCH 1/2] arm64: tegra: Add pwm-fan profile settings

Add support for profiles in device tree to allow different fan settings for trip point temp/hyst/pwm.

Signed-off-by Sandipan Patra <[email protected]>

---
 arch/arm64/boot/dts/nvidia/tegra194-p2972-0000.dts | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

arch/arm64/boot/dts/nvidia/tegra194-p2972-0000.dts +12 -3

index e15d1ea..ff2b980 100644
@@ -219,10 +219,19 @@
 
 	fan: fan {
 		compatible = "pwm-fan";
-		pwms = <&pwm4 0 45334>;
-
-		cooling-levels = <0 64 128 255>;
 		#cooling-cells = <2>;
+		pwms = <&pwm4 0 45334>;
+		profiles {
+			default = "quiet";
+			quiet {
+				state_cap = <4>;
+				cooling-levels = <0 77 120 160 255 255 255 255
 255 255>;
+			};
+			cool {
+				state_cap = <4>;
+				cooling-levels = <0 77 120 160 255 255 255 255
 255 255>;
+			};
+		};
 	};

gpio-keys {
--
2.7.4