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 <frank@xxxxxxxxxxxxxxxxxx>
---
v3:
* Correct possible uninitialised pointer issue.
v2:
* Convert to use feature flag and related macros rather than a separate
field, as suggested in review.
* Reverse sense of flag in superio_exit to simplify feature macro.
---
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..923a9563be92 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(28) /* 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)
--
2.39.1
