[PATCH v3 5/8] thermal: khadas-mcu-fan: Add fan config from platform data Add regulator support

Ronald Claveau
2026-04-17T16:37:23Z

Replace the hardcoded MAX_LEVEL constant and fan register
with values read from platform_data (fan_reg, max_level),
as new MCUs need different values.

Optionally acquire and enable a "fan" regulator supply
at probe time and on resume,
so boards that gate fan power through a regulator are handled.

Signed-off-by: Ronald Claveau <linux-kernel-dev@aliel.fr>
---
drivers/thermal/khadas_mcu_fan.c | 49 +++++++++++++++++++++++++++++++++++-----
1 file changed, 43 insertions(+), 6 deletions(-)

diff --git a/drivers/thermal/khadas_mcu_fan.c b/drivers/thermal/khadas_mcu_fan.c
index d35e5313bea41..24559bf65de46 100644
--- a/drivers/thermal/khadas_mcu_fan.c
+++ b/drivers/thermal/khadas_mcu_fan.c
@@ -13,13 +13,15 @@
#include <linux/regmap.h>
#include <linux/sysfs.h>
#include <linux/thermal.h>
-
-#define MAX_LEVEL 3
+#include <linux/regulator/consumer.h>

struct khadas_mcu_fan_ctx {
struct khadas_mcu *mcu;
+ unsigned int fan_reg;
unsigned int level;
+ unsigned int max_level;
struct thermal_cooling_device *cdev;
+ struct regulator *power;
};

static int khadas_mcu_fan_set_level(struct khadas_mcu_fan_ctx *ctx,
@@ -27,8 +29,7 @@ static int khadas_mcu_fan_set_level(struct khadas_mcu_fan_ctx *ctx,
{
int ret;

- ret = regmap_write(ctx->mcu->regmap, KHADAS_MCU_CMD_FAN_STATUS_CTRL_REG,
- level);
+ ret = regmap_write(ctx->mcu->regmap, ctx->fan_reg, level);
if (ret)
return ret;

@@ -40,7 +41,9 @@ static int khadas_mcu_fan_set_level(struct khadas_mcu_fan_ctx *ctx,
static int khadas_mcu_fan_get_max_state(struct thermal_cooling_device *cdev,
unsigned long *state)
{
- *state = MAX_LEVEL;
+ struct khadas_mcu_fan_ctx *ctx = cdev->devdata;
+
+ *state = ctx->max_level;

return 0;
}
@@ -61,7 +64,7 @@ khadas_mcu_fan_set_cur_state(struct thermal_cooling_device *cdev,
{
struct khadas_mcu_fan_ctx *ctx = cdev->devdata;

- if (state > MAX_LEVEL)
+ if (state > ctx->max_level)
return -EINVAL;

if (state == ctx->level)
@@ -83,11 +86,32 @@ static int khadas_mcu_fan_probe(struct platform_device *pdev)
struct device *dev = &pdev->dev;
struct khadas_mcu_fan_ctx *ctx;
int ret;
+ const struct khadas_mcu_fan_pdata *pdata = dev_get_platdata(&pdev->dev);

ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
if (!ctx)
return -ENOMEM;
+
ctx->mcu = mcu;
+ ctx->fan_reg = pdata->fan_reg;
+ ctx->max_level = pdata->max_level;
+
+ ctx->power = devm_regulator_get_optional(dev->parent, "fan");
+ if (IS_ERR(ctx->power)) {
+ if (PTR_ERR(ctx->power) == -ENODEV)
+ ctx->power = NULL;
+ else
+ return PTR_ERR(ctx->power);
+ }
+
+ if (ctx->power) {
+ ret = regulator_enable(ctx->power);
+ if (ret) {
+ dev_err(dev, "Failed to enable fan power supply: %d\n", ret);
+ return ret;
+ }
+ }
+
platform_set_drvdata(pdev, ctx);

cdev = devm_thermal_of_cooling_device_register(dev->parent,
@@ -124,12 +148,25 @@ static int khadas_mcu_fan_suspend(struct device *dev)

ctx->level = level_save;

+ if (ctx->power) {
+ ret = regulator_disable(ctx->power);
+ if (ret)
+ return ret;
+ }
+
return 0;
}

static int khadas_mcu_fan_resume(struct device *dev)
{
struct khadas_mcu_fan_ctx *ctx = dev_get_drvdata(dev);
+ int ret;
+
+ if (ctx->power) {
+ ret = regulator_enable(ctx->power);
+ if (ret)
+ return ret;
+ }

return khadas_mcu_fan_set_level(ctx, ctx->level);
}

--
2.49.0