From 4119693bd260dabbbf34abf262ece477bc3ed57c Mon Sep 17 00:00:00 2001 From: Frank Crawford Date: Sat, 28 Jan 2023 17:03:02 +1100 Subject: [PATCH] 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: Frank Crawford 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: Guenter Roeck --- drivers/hwmon/it87.c | 26 ++++++++++++++++++-------- 1 file changed, 18 insertions(+), 8 deletions(-) diff --git a/drivers/hwmon/it87.c b/drivers/hwmon/it87.c index a8a6a0ffee82..8c0001be1127 100644 --- a/drivers/hwmon/it87.c +++ b/drivers/hwmon/it87.c @@ -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) { - outb(0x02, ioreg); - outb(0x02, ioreg + 1); + 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)