Commit 4d9983de authored by Armin Wolf's avatar Armin Wolf Committed by Guenter Roeck
Browse files

hwmon: (dell-smm) Make fan/temp sensor number a u8 



Right now, we only use bits 0 to 7 of the fan/temp sensor number
by doing number & 0xff. Passing the value as a u8 makes this
step unnecessary. Also add checks to the ioctl handler since
users might get confused when passing 0x00000101 does the same
as passing 0x00000001.

Tested on a Dell Inspiron 3505.

Signed-off-by: default avatarArmin Wolf <W_Armin@gmx.de>
Reviewed-by: default avatarPali Rohár <pali@kernel.org>
Link: https://lore.kernel.org/r/20220215191113.16640-4-W_Armin@gmx.de


Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
parent ec3db1ec

drivers/hwmon/dell-smm-hwmon.c

+45 −23
Original line number Diff line number Diff line
@@ -21,6 +21,7 @@ 
#include <linux/errno.h>

#include <linux/hwmon.h>

#include <linux/init.h>

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/mutex.h>

#include <linux/platform_device.h>
@@ -250,46 +251,52 @@ static int i8k_smm(struct smm_regs *regs) 
/*

 * Read the fan status.

 */

static int i8k_get_fan_status(const struct dell_smm_data *data, int fan)

static int i8k_get_fan_status(const struct dell_smm_data *data, u8 fan)

{

	struct smm_regs regs = { .eax = I8K_SMM_GET_FAN, };

	struct smm_regs regs = {

		.eax = I8K_SMM_GET_FAN,

		.ebx = fan,

	};



	if (data->disallow_fan_support)

		return -EINVAL;



	regs.ebx = fan & 0xff;

	return i8k_smm(&regs) ? : regs.eax & 0xff;

}



/*

 * Read the fan speed in RPM.

 */

static int i8k_get_fan_speed(const struct dell_smm_data *data, int fan)

static int i8k_get_fan_speed(const struct dell_smm_data *data, u8 fan)

{

	struct smm_regs regs = { .eax = I8K_SMM_GET_SPEED, };

	struct smm_regs regs = {

		.eax = I8K_SMM_GET_SPEED,

		.ebx = fan,

	};



	if (data->disallow_fan_support)

		return -EINVAL;



	regs.ebx = fan & 0xff;

	return i8k_smm(&regs) ? : (regs.eax & 0xffff) * data->i8k_fan_mult;

}



/*

 * Read the fan type.

 */

static int _i8k_get_fan_type(const struct dell_smm_data *data, int fan)

static int _i8k_get_fan_type(const struct dell_smm_data *data, u8 fan)

{

	struct smm_regs regs = { .eax = I8K_SMM_GET_FAN_TYPE, };

	struct smm_regs regs = {

		.eax = I8K_SMM_GET_FAN_TYPE,

		.ebx = fan,

	};



	if (data->disallow_fan_support || data->disallow_fan_type_call)

		return -EINVAL;



	regs.ebx = fan & 0xff;

	return i8k_smm(&regs) ? : regs.eax & 0xff;

}



static int i8k_get_fan_type(struct dell_smm_data *data, int fan)

static int i8k_get_fan_type(struct dell_smm_data *data, u8 fan)

{

	/* I8K_SMM_GET_FAN_TYPE SMM call is expensive, so cache values */

	if (data->fan_type[fan] == INT_MIN)
@@ -301,14 +308,16 @@ static int i8k_get_fan_type(struct dell_smm_data *data, int fan) 
/*

 * Read the fan nominal rpm for specific fan speed.

 */

static int __init i8k_get_fan_nominal_speed(const struct dell_smm_data *data, int fan, int speed)

static int __init i8k_get_fan_nominal_speed(const struct dell_smm_data *data, u8 fan, int speed)

{

	struct smm_regs regs = { .eax = I8K_SMM_GET_NOM_SPEED, };

	struct smm_regs regs = {

		.eax = I8K_SMM_GET_NOM_SPEED,

		.ebx = fan | (speed << 8),

	};



	if (data->disallow_fan_support)

		return -EINVAL;



	regs.ebx = (fan & 0xff) | (speed << 8);

	return i8k_smm(&regs) ? : (regs.eax & 0xffff) * data->i8k_fan_mult;

}
@@ -329,7 +338,7 @@ static int i8k_enable_fan_auto_mode(const struct dell_smm_data *data, bool enabl 
/*

 * Set the fan speed (off, low, high, ...).

 */

static int i8k_set_fan(const struct dell_smm_data *data, int fan, int speed)

static int i8k_set_fan(const struct dell_smm_data *data, u8 fan, int speed)

{

	struct smm_regs regs = { .eax = I8K_SMM_SET_FAN, };
@@ -337,33 +346,35 @@ static int i8k_set_fan(const struct dell_smm_data *data, int fan, int speed) 
		return -EINVAL;



	speed = (speed < 0) ? 0 : ((speed > data->i8k_fan_max) ? data->i8k_fan_max : speed);

	regs.ebx = (fan & 0xff) | (speed << 8);

	regs.ebx = fan | (speed << 8);



	return i8k_smm(&regs);

}



static int __init i8k_get_temp_type(int sensor)

static int __init i8k_get_temp_type(u8 sensor)

{

	struct smm_regs regs = { .eax = I8K_SMM_GET_TEMP_TYPE, };

	struct smm_regs regs = {

		.eax = I8K_SMM_GET_TEMP_TYPE,

		.ebx = sensor,

	};



	regs.ebx = sensor & 0xff;

	return i8k_smm(&regs) ? : regs.eax & 0xff;

}



/*

 * Read the cpu temperature.

 */

static int _i8k_get_temp(int sensor)

static int _i8k_get_temp(u8 sensor)

{

	struct smm_regs regs = {

		.eax = I8K_SMM_GET_TEMP,

		.ebx = sensor & 0xff,

		.ebx = sensor,

	};



	return i8k_smm(&regs) ? : regs.eax & 0xff;

}



static int i8k_get_temp(int sensor)

static int i8k_get_temp(u8 sensor)

{

	int temp = _i8k_get_temp(sensor);
@@ -496,6 +507,9 @@ static long i8k_ioctl(struct file *fp, unsigned int cmd, unsigned long arg) 
		if (copy_from_user(&val, argp, sizeof(int)))

			return -EFAULT;



		if (val > U8_MAX || val < 0)

			return -EINVAL;



		val = i8k_get_fan_speed(data, val);

		break;
@@ -503,6 +517,9 @@ static long i8k_ioctl(struct file *fp, unsigned int cmd, unsigned long arg) 
		if (copy_from_user(&val, argp, sizeof(int)))

			return -EFAULT;



		if (val > U8_MAX || val < 0)

			return -EINVAL;



		val = i8k_get_fan_status(data, val);

		break;
@@ -513,6 +530,9 @@ static long i8k_ioctl(struct file *fp, unsigned int cmd, unsigned long arg) 
		if (copy_from_user(&val, argp, sizeof(int)))

			return -EFAULT;



		if (val > U8_MAX || val < 0)

			return -EINVAL;



		if (copy_from_user(&speed, argp + 1, sizeof(int)))

			return -EFAULT;
@@ -920,7 +940,8 @@ static int __init dell_smm_init_hwmon(struct device *dev) 
{

	struct dell_smm_data *data = dev_get_drvdata(dev);

	struct device *dell_smm_hwmon_dev;

	int i, state, err;

	int state, err;

	u8 i;



	for (i = 0; i < DELL_SMM_NO_TEMP; i++) {

		data->temp_type[i] = i8k_get_temp_type(i);
@@ -1236,7 +1257,8 @@ static int __init dell_smm_probe(struct platform_device *pdev) 
{

	struct dell_smm_data *data;

	const struct dmi_system_id *id, *fan_control;

	int fan, ret;

	int ret;

	u8 fan;



	data = devm_kzalloc(&pdev->dev, sizeof(struct dell_smm_data), GFP_KERNEL);

	if (!data)