Commit 4119693b authored by Frank Crawford's avatar Frank Crawford Committed by Guenter Roeck
Browse files

hwmon: (it87) Allow disabling exiting of configuration mode 



Disabling configuration mode on some chips can result in system
hang-ups and access failures to the Super-IO chip at the
second SIO address. Never exit configuration mode on these
chips to avoid the problem.

This patch should be applied in conjunction with a previous one to
initialise the second chip for certain mother boards.

Signed-off-by: default avatarFrank Crawford <frank@crawford.emu.id.au>
Link: https://lore.kernel.org/r/20230128060308.1549707-2-frank@crawford.emu.id.au


[groeck: Change feature bit from 28 to 19 to be continuous]
Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
parent 12087a36

drivers/hwmon/it87.c

+18 −8
Original line number Diff line number Diff line
@@ -128,10 +128,12 @@ static inline int superio_enter(int ioreg) 
	return 0;

}



static inline void superio_exit(int ioreg)

static inline void superio_exit(int ioreg, bool noexit)

{

	if (!noexit) {

		outb(0x02, ioreg);

		outb(0x02, ioreg + 1);

	}

	release_region(ioreg, 2);

}
@@ -300,6 +302,13 @@ struct it87_devices { 
#define FEAT_PWM_FREQ2		BIT(16)	/* Separate pwm freq 2 */

#define FEAT_SIX_TEMP		BIT(17)	/* Up to 6 temp sensors */

#define FEAT_VIN3_5V		BIT(18)	/* VIN3 connected to +5V */

/*

 * Disabling configuration mode on some chips can result in system

 * hang-ups and access failures to the Super-IO chip at the

 * second SIO address. Never exit configuration mode on these

 * chips to avoid the problem.

 */

#define FEAT_CONF_NOEXIT	BIT(19)	/* Chip should not exit conf mode */



static const struct it87_devices it87_devices[] = {

	[it87] = {
@@ -493,6 +502,7 @@ static const struct it87_devices it87_devices[] = { 
#define has_pwm_freq2(data)	((data)->features & FEAT_PWM_FREQ2)

#define has_six_temp(data)	((data)->features & FEAT_SIX_TEMP)

#define has_vin3_5v(data)	((data)->features & FEAT_VIN3_5V)

#define has_conf_noexit(data)	((data)->features & FEAT_CONF_NOEXIT)



struct it87_sio_data {

	int sioaddr;
@@ -2404,7 +2414,7 @@ static int __init it87_find(int sioaddr, unsigned short *address, 
{

	int err;

	u16 chip_type;

	const struct it87_devices *config;

	const struct it87_devices *config = NULL;



	err = superio_enter(sioaddr);

	if (err)
@@ -2489,6 +2499,8 @@ static int __init it87_find(int sioaddr, unsigned short *address, 
		goto exit;

	}



	config = &it87_devices[sio_data->type];



	superio_select(sioaddr, PME);

	if (!(superio_inb(sioaddr, IT87_ACT_REG) & 0x01)) {

		pr_info("Device not activated, skipping\n");
@@ -2508,8 +2520,6 @@ static int __init it87_find(int sioaddr, unsigned short *address, 
		it87_devices[sio_data->type].suffix,

		*address, sio_data->revision);



	config = &it87_devices[sio_data->type];



	/* in7 (VSB or VCCH5V) is always internal on some chips */

	if (has_in7_internal(config))

		sio_data->internal |= BIT(1);
@@ -2827,7 +2837,7 @@ static int __init it87_find(int sioaddr, unsigned short *address, 
		sio_data->skip_pwm |= dmi_data->skip_pwm;



exit:

	superio_exit(sioaddr);

	superio_exit(sioaddr, config ? has_conf_noexit(config) : false);

	return err;

}
@@ -3213,7 +3223,7 @@ static void it87_resume_sio(struct platform_device *pdev) 
			     reg2c);

	}



	superio_exit(data->sioaddr);

	superio_exit(data->sioaddr, has_conf_noexit(data));

}



static int it87_resume(struct device *dev)