From 9989b3c0ff9771760c103d46e6b5e8645fd3d836 Mon Sep 17 00:00:00 2001 From: Frank Crawford Date: Sun, 16 Apr 2023 14:25:07 +1000 Subject: [PATCH] hwmon: (it87) Disable SMBus access for environmental controller registers. Add functions to disable and re-enable access by the SMBus for specific chips. Signed-off-by: Frank Crawford Signed-off-by: Guenter Roeck --- drivers/hwmon/it87.c | 58 ++++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 56 insertions(+), 2 deletions(-) diff --git a/drivers/hwmon/it87.c b/drivers/hwmon/it87.c index f774a07..b74dd86 100644 --- a/drivers/hwmon/it87.c +++ b/drivers/hwmon/it87.c @@ -162,8 +162,11 @@ static inline void superio_exit(int ioreg, bool noexit) #define IT8623E_DEVID 0x8623 #define IT8628E_DEVID 0x8628 #define IT87952E_DEVID 0x8695 -#define IT87_ACT_REG 0x30 -#define IT87_BASE_REG 0x60 + +/* Logical device 4 (Environmental Monitor) registers */ +#define IT87_ACT_REG 0x30 +#define IT87_BASE_REG 0x60 +#define IT87_SPECIAL_CFG_REG 0xf3 /* special configuration register */ /* Logical device 7 registers (IT8712F and later) */ #define IT87_SIO_GPIO1_REG 0x25 @@ -284,6 +287,8 @@ struct it87_devices { u32 features; u8 peci_mask; u8 old_peci_mask; + u8 smbus_bitmap; /* SMBus enable bits in extra config register */ + u8 ec_special_config; }; #define FEAT_12MV_ADC BIT(0) @@ -533,6 +538,8 @@ struct it87_sio_data { u8 skip_fan; u8 skip_pwm; u8 skip_temp; + u8 smbus_bitmap; + u8 ec_special_config; }; /* @@ -547,6 +554,9 @@ struct it87_data { u8 peci_mask; u8 old_peci_mask; + u8 smbus_bitmap; /* !=0 if SMBus needs to be disabled */ + u8 ec_special_config; /* EC special config register restore value */ + unsigned short addr; const char *name; struct mutex update_lock; @@ -701,6 +711,39 @@ static const unsigned int pwm_freq[8] = { 750000, }; +static int smbus_disable(struct it87_data *data) +{ + int err; + + if (data->smbus_bitmap) { + err = superio_enter(data->sioaddr); + if (err) + return err; + superio_select(data->sioaddr, PME); + superio_outb(data->sioaddr, IT87_SPECIAL_CFG_REG, + data->ec_special_config & ~data->smbus_bitmap); + superio_exit(data->sioaddr, has_conf_noexit(data)); + } + return 0; +} + +static int smbus_enable(struct it87_data *data) +{ + int err; + + if (data->smbus_bitmap) { + err = superio_enter(data->sioaddr); + if (err) + return err; + + superio_select(data->sioaddr, PME); + superio_outb(data->sioaddr, IT87_SPECIAL_CFG_REG, + data->ec_special_config); + superio_exit(data->sioaddr, has_conf_noexit(data)); + } + return 0; +} + /* * Must be called with data->update_lock held, except during initialization. * We ignore the IT87 BUSY flag at this moment - it could lead to deadlocks, @@ -2859,6 +2902,15 @@ static int __init it87_find(int sioaddr, unsigned short *address, if (dmi_data) sio_data->skip_pwm |= dmi_data->skip_pwm; + if (config->smbus_bitmap) { + u8 reg; + + superio_select(sioaddr, PME); + reg = superio_inb(sioaddr, IT87_SPECIAL_CFG_REG); + sio_data->ec_special_config = reg; + sio_data->smbus_bitmap = reg & config->smbus_bitmap; + } + exit: superio_exit(sioaddr, config ? has_conf_noexit(config) : false); return err; @@ -3094,6 +3146,8 @@ static int it87_probe(struct platform_device *pdev) data->addr = res->start; data->sioaddr = sio_data->sioaddr; data->type = sio_data->type; + data->smbus_bitmap = sio_data->smbus_bitmap; + data->ec_special_config = sio_data->ec_special_config; data->features = it87_devices[sio_data->type].features; data->peci_mask = it87_devices[sio_data->type].peci_mask; data->old_peci_mask = it87_devices[sio_data->type].old_peci_mask; -- 2.7.4