On ThinkPad X120e, fan speed is incorrectly reported in ticks per revolution rather than RPM. Recaculate the fan speed value reported for ThinkPad X120e to RPM based on a 22.5 kHz clock. Based on the information on https://www.thinkwiki.org/wiki/How_to_control_fan_speed, the same problem is highly likely to be relevant to at least Edge11, but Edge11 is not addressed in this patch. Signed-off-by: Sybil Isabel Dorsett <sybdorsett@xxxxxxxxx> --- Notes: v2: addressed review comments - name of the new variable is changed from "fan_speed_requires_conversion" to "fan_speed_in_tpr"; - rephrased the commit message; - "KHz" is respelled as "kHz". drivers/platform/x86/thinkpad_acpi.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c index 1fcb0f996..e7778ea41 100644 --- a/drivers/platform/x86/thinkpad_acpi.c +++ b/drivers/platform/x86/thinkpad_acpi.c @@ -7885,6 +7885,7 @@ static struct ibm_struct volume_driver_data = { #define FAN_NS_CTRL_STATUS BIT(2) /* Bit which determines control is enabled or not */ #define FAN_NS_CTRL BIT(4) /* Bit which determines control is by host or EC */ +#define FAN_CLOCK_TPM (22500*60) /* Ticks per minute for a 22.5 kHz clock */ enum { /* Fan control constants */ fan_status_offset = 0x2f, /* EC register 0x2f */ @@ -7940,6 +7941,7 @@ static int fan_watchdog_maxinterval; static bool fan_with_ns_addr; static bool ecfw_with_fan_dec_rpm; +static bool fan_speed_in_tpr; static struct mutex fan_mutex; @@ -8142,8 +8144,11 @@ static int fan_get_speed(unsigned int *speed) !acpi_ec_read(fan_rpm_offset + 1, &hi))) return -EIO; - if (likely(speed)) + if (likely(speed)) { *speed = (hi << 8) | lo; + if (fan_speed_in_tpr && *speed != 0) + *speed = FAN_CLOCK_TPM / *speed; + } break; case TPACPI_FAN_RD_TPEC_NS: if (!acpi_ec_read(fan_rpm_status_ns, &lo)) @@ -8176,8 +8181,11 @@ static int fan2_get_speed(unsigned int *speed) if (rc) return -EIO; - if (likely(speed)) + if (likely(speed)) { *speed = (hi << 8) | lo; + if (fan_speed_in_tpr && *speed != 0) + *speed = FAN_CLOCK_TPM / *speed; + } break; case TPACPI_FAN_RD_TPEC_NS: @@ -8788,6 +8796,7 @@ static const struct attribute_group fan_driver_attr_group = { #define TPACPI_FAN_NOFAN 0x0008 /* no fan available */ #define TPACPI_FAN_NS 0x0010 /* For EC with non-Standard register addresses */ #define TPACPI_FAN_DECRPM 0x0020 /* For ECFW's with RPM in register as decimal */ +#define TPACPI_FAN_TPR 0x0040 /* Fan speed is in Ticks Per Revolution */ static const struct tpacpi_quirk fan_quirk_table[] __initconst = { TPACPI_QEC_IBM('1', 'Y', TPACPI_FAN_Q1), @@ -8817,6 +8826,7 @@ static const struct tpacpi_quirk fan_quirk_table[] __initconst = { TPACPI_Q_LNV3('R', '0', 'V', TPACPI_FAN_NS), /* 11e Gen5 KL-Y */ TPACPI_Q_LNV3('N', '1', 'O', TPACPI_FAN_NOFAN), /* X1 Tablet (2nd gen) */ TPACPI_Q_LNV3('R', '0', 'Q', TPACPI_FAN_DECRPM),/* L480 */ + TPACPI_Q_LNV('8', 'F', TPACPI_FAN_TPR), /* ThinkPad x120e */ }; static int __init fan_init(struct ibm_init_struct *iibm) @@ -8887,6 +8897,8 @@ static int __init fan_init(struct ibm_init_struct *iibm) if (quirks & TPACPI_FAN_Q1) fan_quirk1_setup(); + if (quirks & TPACPI_FAN_TPR) + fan_speed_in_tpr = true; /* Try and probe the 2nd fan */ tp_features.second_fan = 1; /* needed for get_speed to work */ res = fan2_get_speed(&speed); -- 2.39.5