Commit c0d79987 authored by Armin Wolf's avatar Armin Wolf Committed by Guenter Roeck
Browse files

hwmon: (dell-smm) Speed up setting of fan speed 



When setting the fan speed, i8k_set_fan() calls i8k_get_fan_status(),
causing an unnecessary SMM call since from the two users of this
function, only i8k_ioctl_unlocked() needs to know the new fan status
while dell_smm_write() ignores the new fan status.
Since SMM calls can be very slow while also making error reporting
difficult for dell_smm_write(), remove the function call from
i8k_set_fan() and call it separately in i8k_ioctl_unlocked().

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/20211021190531.17379-6-W_Armin@gmx.de


Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
parent 927d89ee

drivers/hwmon/dell-smm-hwmon.c

+8 −4
Original line number Diff line number Diff line
@@ -327,7 +327,7 @@ static int i8k_enable_fan_auto_mode(const struct dell_smm_data *data, bool enabl 
}



/*

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

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

 */

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

{
@@ -339,7 +339,7 @@ static int i8k_set_fan(const struct dell_smm_data *data, int fan, int speed) 
	speed = (speed < 0) ? 0 : ((speed > data->i8k_fan_max) ? data->i8k_fan_max : speed);

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



	return i8k_smm(&regs) ? : i8k_get_fan_status(data, fan);

	return i8k_smm(&regs);

}



static int __init i8k_get_temp_type(int sensor)
@@ -453,7 +453,7 @@ static int 
i8k_ioctl_unlocked(struct file *fp, struct dell_smm_data *data, unsigned int cmd, unsigned long arg)

{

	int val = 0;

	int speed;

	int speed, err;

	unsigned char buff[16];

	int __user *argp = (int __user *)arg;
@@ -513,7 +513,11 @@ i8k_ioctl_unlocked(struct file *fp, struct dell_smm_data *data, unsigned int cmd 
		if (copy_from_user(&speed, argp + 1, sizeof(int)))

			return -EFAULT;



		val = i8k_set_fan(data, val, speed);

		err = i8k_set_fan(data, val, speed);

		if (err < 0)

			return err;



		val = i8k_get_fan_status(data, val);

		break;



	default: