diff options
author | Henrique de Moraes Holschuh <hmh@hmh.eng.br> | 2006-11-24 13:47:08 (GMT) |
---|---|---|
committer | Len Brown <len.brown@intel.com> | 2006-12-07 06:38:38 (GMT) |
commit | 60eb0b35a9cc3400251cb4028d100e350649cf8a (patch) | |
tree | 2f655a273572e46b6c4f662071d027e57cad1bcf /drivers/acpi/ibm_acpi.c | |
parent | a26f878abcd0491906b5bbac8dd174f27019e907 (diff) | |
download | linux-fsl-qoriq-60eb0b35a9cc3400251cb4028d100e350649cf8a.tar.xz |
ACPI: ibm-acpi: Implement direct-ec-access thermal reading modes for up to 16 sensors
This patch extends ibm-acpi to support reading thermal sensors directly
through ACPI EC register access. It uses a DMI match to detect ThinkPads
with a new-style embedded controller, that are known to have forward-
compatible register maps and use 0x00 to fill in non-used registers and
export thermal sensors at EC offsets 0x78-7F and 0xC0-C7.
Direct ACPI EC register access is implemented for 8-sensor and 16-sensor
new-style ThinkPad controller firmwares as an experimental feature. The
code does some limited sanity checks on the temperatures read through EC
access, and will default to the old ACPI TMP0-7 mode if anything is amiss.
Userspace ABI is not changed for 8 sensors, but /proc/acpi/ibm/thermal is
extended for 16 sensors if the firmware supports 16 sensors.
A documentation update is also provided.
The information about the ThinkPad register map was determined by studying
ibm-acpi "ecdump" output from various ThinkPad models, submitted by
subscribers of the linux-thinkpad mailinglist. Futher information was
gathered from the DSDT tables, as they describe the EC register map in
recent ThinkPads.
DSDT source shows that TMP0-7 access and direct register access are
actually the same thing on these firmwares, but unfortunately IBM never
did update their DSDT EC register map to export TMP8-TMP15 for the second
range of sensors.
Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Diffstat (limited to 'drivers/acpi/ibm_acpi.c')
-rw-r--r-- | drivers/acpi/ibm_acpi.c | 93 |
1 files changed, 91 insertions, 2 deletions
diff --git a/drivers/acpi/ibm_acpi.c b/drivers/acpi/ibm_acpi.c index baf9492..1703c61 100644 --- a/drivers/acpi/ibm_acpi.c +++ b/drivers/acpi/ibm_acpi.c @@ -80,6 +80,7 @@ #include <linux/proc_fs.h> #include <linux/backlight.h> #include <asm/uaccess.h> +#include <linux/dmi.h> #include <acpi/acpi_drivers.h> #include <acpi/acnamesp.h> @@ -221,13 +222,17 @@ enum thermal_access_mode { IBMACPI_THERMAL_NONE = 0, /* No thermal support */ IBMACPI_THERMAL_ACPI_TMP07, /* Use ACPI TMP0-7 */ IBMACPI_THERMAL_ACPI_UPDT, /* Use ACPI TMP0-7 with UPDT */ + IBMACPI_THERMAL_TPEC_8, /* Use ACPI EC regs, 8 sensors */ + IBMACPI_THERMAL_TPEC_16, /* Use ACPI EC regs, 16 sensors */ }; -#define IBMACPI_MAX_THERMAL_SENSORS 8 /* Max thermal sensors supported */ +#define IBMACPI_MAX_THERMAL_SENSORS 16 /* Max thermal sensors supported */ struct ibm_thermal_sensors_struct { s32 temp[IBMACPI_MAX_THERMAL_SENSORS]; }; +static int ibm_thinkpad_ec_found; + struct ibm_struct { char *name; char param[32]; @@ -1290,7 +1295,52 @@ static enum thermal_access_mode thermal_read_mode; static int thermal_init(void) { - if (acpi_evalf(ec_handle, NULL, "TMP7", "qv")) { + u8 t, ta1, ta2; + int i; + int acpi_tmp7 = acpi_evalf(ec_handle, NULL, "TMP7", "qv"); + + if (ibm_thinkpad_ec_found && experimental) { + /* + * Direct EC access mode: sensors at registers + * 0x78-0x7F, 0xC0-0xC7. Registers return 0x00 for + * non-implemented, thermal sensors return 0x80 when + * not available + */ + + ta1 = ta2 = 0; + for (i = 0; i < 8; i++) { + if (likely(acpi_ec_read(0x78 + i, &t))) { + ta1 |= t; + } else { + ta1 = 0; + break; + } + if (likely(acpi_ec_read(0xC0 + i, &t))) { + ta2 |= t; + } else { + ta1 = 0; + break; + } + } + if (ta1 == 0) { + /* This is sheer paranoia, but we handle it anyway */ + if (acpi_tmp7) { + printk(IBM_ERR + "ThinkPad ACPI EC access misbehaving, " + "falling back to ACPI TMPx access mode\n"); + thermal_read_mode = IBMACPI_THERMAL_ACPI_TMP07; + } else { + printk(IBM_ERR + "ThinkPad ACPI EC access misbehaving, " + "disabling thermal sensors access\n"); + thermal_read_mode = IBMACPI_THERMAL_NONE; + } + } else { + thermal_read_mode = + (ta2 != 0) ? + IBMACPI_THERMAL_TPEC_16 : IBMACPI_THERMAL_TPEC_8; + } + } else if (acpi_tmp7) { if (acpi_evalf(ec_handle, NULL, "UPDT", "qv")) { /* 600e/x, 770e, 770x */ thermal_read_mode = IBMACPI_THERMAL_ACPI_UPDT; @@ -1309,12 +1359,30 @@ static int thermal_init(void) static int thermal_get_sensors(struct ibm_thermal_sensors_struct *s) { int i, t; + s8 tmp; char tmpi[] = "TMPi"; if (!s) return -EINVAL; switch (thermal_read_mode) { +#if IBMACPI_MAX_THERMAL_SENSORS >= 16 + case IBMACPI_THERMAL_TPEC_16: + for (i = 0; i < 8; i++) { + if (!acpi_ec_read(0xC0 + i, &tmp)) + return -EIO; + s->temp[i + 8] = tmp * 1000; + } + /* fallthrough */ +#endif + case IBMACPI_THERMAL_TPEC_8: + for (i = 0; i < 8; i++) { + if (!acpi_ec_read(0x78 + i, &tmp)) + return -EIO; + s->temp[i] = tmp * 1000; + } + return (thermal_read_mode == IBMACPI_THERMAL_TPEC_16) ? 16 : 8; + case IBMACPI_THERMAL_ACPI_UPDT: if (!acpi_evalf(ec_handle, NULL, "UPDT", "v")) return -EIO; @@ -2052,6 +2120,24 @@ static void acpi_ibm_exit(void) remove_proc_entry(IBM_DIR, acpi_root_dir); } +static int __init check_dmi_for_ec(void) +{ + struct dmi_device *dev = NULL; + + /* + * ThinkPad T23 or newer, A31 or newer, R50e or newer, + * X32 or newer, all Z series; Some models must have an + * up-to-date BIOS or they will not be detected. + * + * See http://thinkwiki.org/wiki/List_of_DMI_IDs + */ + while ((dev = dmi_find_device(DMI_DEV_TYPE_OEM_STRING, NULL, dev))) { + if (strstr(dev->name, "IBM ThinkPad Embedded Controller")) + return 1; + } + return 0; +} + static int __init acpi_ibm_init(void) { int ret, i; @@ -2071,6 +2157,9 @@ static int __init acpi_ibm_init(void) return -ENODEV; } + /* Models with newer firmware report the EC in DMI */ + ibm_thinkpad_ec_found = check_dmi_for_ec(); + /* these handles are not required */ IBM_HANDLE_INIT(vid); IBM_HANDLE_INIT(vid2); |