Re: [PATCH] Fix to correct wrong temp reporting on some ThinkPads

Ilpo Järvinen
2024-02-06T11:03:49Z

On Thu, 1 Feb 2024, Vishnu Sankar wrote:

> Added non-standard thermal register support for some ThinkPads.
>
> Some of the Thinkpads use a non-standard ECFW which uses different
> thermal register addresses.
> This is a Fix to correct the wrong temperature reporting on
> those systems.
>
> Tested on Lenovo Thinkpad L13 Yoga Gen2
>
> Suggested-by: Mark Pearson <mpearson-lenovo@squebb.ca>
> Signed-off-by: Vishnu Sankar <vishnuocv@gmail.com>
> ---
> drivers/platform/x86/thinkpad_acpi.c | 132 ++++++++++++++++++++-------
> 1 file changed, 97 insertions(+), 35 deletions(-)
>
> diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c
> index c4895e9bc714..a4631196513f 100644
> --- a/drivers/platform/x86/thinkpad_acpi.c
> +++ b/drivers/platform/x86/thinkpad_acpi.c
> @@ -6126,12 +6126,15 @@ enum thermal_access_mode {
> TPACPI_THERMAL_ACPI_TMP07, /* Use ACPI TMP0-7 */
> TPACPI_THERMAL_ACPI_UPDT, /* Use ACPI TMP0-7 with UPDT */
> TPACPI_THERMAL_TPEC_8, /* Use ACPI EC regs, 8 sensors */
> + TPACPI_THERMAL_TPEC_12, /* Use ACPI EC regs, 12 sensors */
> TPACPI_THERMAL_TPEC_16, /* Use ACPI EC regs, 16 sensors */
> };
>
> enum { /* TPACPI_THERMAL_TPEC_* */
> TP_EC_THERMAL_TMP0 = 0x78, /* ACPI EC regs TMP 0..7 */
> TP_EC_THERMAL_TMP8 = 0xC0, /* ACPI EC regs TMP 8..15 */
> + TP_EC_THERMAL_TMP0_NS = 0xA8, /* ACPI EC Non-Standard regs TMP 0..7 */
> + TP_EC_THERMAL_TMP8_NS = 0xB8, /* ACPI EC Non-standard regs TMP 8..11 */
> TP_EC_FUNCREV = 0xEF, /* ACPI EC Functional revision */
> TP_EC_THERMAL_TMP_NA = -128, /* ACPI EC sensor not available */
>
> @@ -6144,8 +6147,22 @@ struct ibm_thermal_sensors_struct {
> s32 temp[TPACPI_MAX_THERMAL_SENSORS];
> };
>
> +static const struct tpacpi_quirk thermal_quirk_table[] __initconst = {
> + /* Non-standard address for thermal registers on some ThinkPads */
> + TPACPI_Q_LNV3('R', '1', 'F', true), /* L13 Yoga Gen 2 */
> + TPACPI_Q_LNV3('N', '2', 'U', true), /* X13 Yoga Gen 2*/
> + TPACPI_Q_LNV3('R', '0', 'R', true), /* L380 */
> + TPACPI_Q_LNV3('R', '1', '5', true), /* L13 Yoga Gen 1*/
> + TPACPI_Q_LNV3('R', '1', '0', true), /* L390 */
> + TPACPI_Q_LNV3('N', '2', 'L', true), /* X13 Yoga Gen 1*/
> + TPACPI_Q_LNV3('R', '0', 'T', true), /* 11e Gen5 GL*/
> + TPACPI_Q_LNV3('R', '1', 'D', true), /* 11e Gen5 GL-R*/
> + TPACPI_Q_LNV3('R', '0', 'V', true), /* 11e Gen5 KL-Y*/
> +};
> +
> static enum thermal_access_mode thermal_read_mode;
> static bool thermal_use_labels;
> +static bool thermal_with_ns_address; /*Non-standard thermal reg address*/
>
> /* idx is zero-based */
> static int thermal_get_sensor(int idx, s32 *value)
> @@ -6154,7 +6171,7 @@ static int thermal_get_sensor(int idx, s32 *value)
> s8 tmp;
> char tmpi[5];
>
> - t = TP_EC_THERMAL_TMP0;
> + t = thermal_with_ns_address ? TP_EC_THERMAL_TMP0_NS : TP_EC_THERMAL_TMP0;
>
> switch (thermal_read_mode) {
> #if TPACPI_MAX_THERMAL_SENSORS >= 16
> @@ -6174,6 +6191,21 @@ static int thermal_get_sensor(int idx, s32 *value)
> }
> break;
>
> + /* The Non-standard EC uses 12 Thermal areas */
> + case TPACPI_THERMAL_TPEC_12:
> + if (idx <= 11) {
> + if (idx <= 7) {
> + if (!acpi_ec_read(TP_EC_THERMAL_TMP0_NS + idx, &tmp))
> + return -EIO;
> + } else {
> + if (!acpi_ec_read(TP_EC_THERMAL_TMP8_NS + (idx - 8), &tmp))
> + return -EIO;
> + }
> + *value = tmp * 1000;
> + return 0;
> + }
> + break;

A code reader would be served much better if this convoluted logic is
simplied to:

case TPACPI_THERMAL_TPEC_12:
if (idx >= 12)
return -EINVAL;

if (idx <= 7)
ec_offset = TP_EC_THERMAL_TMP0_NS + idx;
else
ec_offset = TP_EC_THERMAL_TMP8_NS + (idx - 8);

if (!acpi_ec_read(ec_offset, &tmp))
return -EIO;

*value = tmp * 1000;
return 0;

I know it's different from the pre-existing style but to me this reads
much better.

> +
> case TPACPI_THERMAL_ACPI_UPDT:
> if (idx <= 7) {
> snprintf(tmpi, sizeof(tmpi), "TMP%c", '0' + idx);
> @@ -6219,6 +6251,8 @@ static int thermal_get_sensors(struct ibm_thermal_sensors_struct *s)
>
> if (thermal_read_mode == TPACPI_THERMAL_TPEC_16)
> n = 16;
> + else if (thermal_read_mode == TPACPI_THERMAL_TPEC_12)
> + n = 12;
>
> for (i = 0 ; i < n; i++) {
> res = thermal_get_sensor(i, &s->temp[i]);
> @@ -6317,18 +6351,36 @@ static struct attribute *thermal_temp_input_attr[] = {
> NULL
> };
>
> +#define to_dev_attr(_attr) container_of(_attr, struct device_attribute, attr)
> +
> static umode_t thermal_attr_is_visible(struct kobject *kobj,
> struct attribute *attr, int n)
> {
> - if (thermal_read_mode == TPACPI_THERMAL_NONE)
> + struct device_attribute *dev_attr = to_dev_attr(attr);
> + struct sensor_device_attribute *sensor_attr =
> + to_sensor_dev_attr(dev_attr);
> +
> + int idx = sensor_attr->index;
> +
> + switch (thermal_read_mode) {
> + case TPACPI_THERMAL_NONE:
> return 0;
>
> - if (attr == THERMAL_ATTRS(8) || attr == THERMAL_ATTRS(9) ||
> - attr == THERMAL_ATTRS(10) || attr == THERMAL_ATTRS(11) ||
> - attr == THERMAL_ATTRS(12) || attr == THERMAL_ATTRS(13) ||
> - attr == THERMAL_ATTRS(14) || attr == THERMAL_ATTRS(15)) {
> - if (thermal_read_mode != TPACPI_THERMAL_TPEC_16)
> + case TPACPI_THERMAL_ACPI_TMP07:
> + case TPACPI_THERMAL_ACPI_UPDT:
> + case TPACPI_THERMAL_TPEC_8:
> + if (idx >= 8)
> + return 0;
> + break;
> +
> + case TPACPI_THERMAL_TPEC_12:
> + if (idx >= 12)
> return 0;
> + break;
> +
> + default:
> + break;
> +
> }
>
> return attr->mode;
> @@ -6398,40 +6450,50 @@ static int __init thermal_init(struct ibm_init_struct *iibm)
> if (!acpi_ec_read(TP_EC_FUNCREV, &ver))
> pr_warn("Thinkpad ACPI EC unable to access EC version\n");
>
> - ta1 = ta2 = 0;
> - for (i = 0; i < 8; i++) {
> - if (acpi_ec_read(TP_EC_THERMAL_TMP0 + i, &t)) {
> - ta1 |= t;
> - } else {
> - ta1 = 0;
> - break;
> - }
> - if (ver < 3) {
> - if (acpi_ec_read(TP_EC_THERMAL_TMP8 + i, &t)) {
> - ta2 |= t;
> + /* Quirks to check non-standard EC */
> + thermal_with_ns_address = tpacpi_check_quirks(thermal_quirk_table,
> + ARRAY_SIZE(thermal_quirk_table));
> +
> + /* Support for Thinkpads with non-standard address */
> + if (thermal_with_ns_address) {
> + pr_info("ECFW with non-standard thermal registers found\n");
> + thermal_read_mode = TPACPI_THERMAL_TPEC_12;
> + } else {
> + ta1 = ta2 = 0;
> + for (i = 0; i < 8; i++) {
> + if (acpi_ec_read(TP_EC_THERMAL_TMP0 + i, &t)) {
> + ta1 |= t;
> } else {
> ta1 = 0;
> break;
> }
> + if (ver < 3) {
> + if (acpi_ec_read(TP_EC_THERMAL_TMP8 + i, &t)) {
> + ta2 |= t;
> + } else {
> + ta1 = 0;
> + break;
> + }
> + }
> }
> - }
> - if (ta1 == 0) {
> - /* This is sheer paranoia, but we handle it anyway */
> - if (acpi_tmp7) {
> - pr_err("ThinkPad ACPI EC access misbehaving, falling back to ACPI TMPx access mode\n");
> - thermal_read_mode = TPACPI_THERMAL_ACPI_TMP07;
> - } else {
> - pr_err("ThinkPad ACPI EC access misbehaving, disabling thermal sensors access\n");
> - thermal_read_mode = TPACPI_THERMAL_NONE;
> - }
> - } else {
> - if (ver >= 3) {
> - thermal_read_mode = TPACPI_THERMAL_TPEC_8;
> - thermal_use_labels = true;
> + if (ta1 == 0) {
> + /* This is sheer paranoia, but we handle it anyway */
> + if (acpi_tmp7) {
> + pr_err("ThinkPad ACPI EC access misbehaving, falling back to ACPI TMPx access mode\n");
> + thermal_read_mode = TPACPI_THERMAL_ACPI_TMP07;
> + } else {
> + pr_err("ThinkPad ACPI EC access misbehaving, disabling thermal sensors access\n");
> + thermal_read_mode = TPACPI_THERMAL_NONE;
> + }
> } else {
> - thermal_read_mode =
> - (ta2 != 0) ?
> - TPACPI_THERMAL_TPEC_16 : TPACPI_THERMAL_TPEC_8;
> + if (ver >= 3) {
> + thermal_read_mode = TPACPI_THERMAL_TPEC_8;
> + thermal_use_labels = true;
> + } else {
> + thermal_read_mode =
> + (ta2 != 0) ?
> + TPACPI_THERMAL_TPEC_16 : TPACPI_THERMAL_TPEC_8;
> + }

This entire thermal read mode detection should be refactored into
thermal_detect_read_mode() helper (in a separate patch before this one).
The helper would mitigate the current runaway indentation problem because
the helper function can return its decision mid-function so the code after
that return does not need an else block reducing the indentation level.

> }
> }
> } else if (acpi_tmp7) {
>

--
i.