Something went wrong. Try again.
(I'm so sorry!) Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux
Something went wrong. Try again.
123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236// SPDX-License-Identifier: GPL-2.0+/* * Thermal sensor subsystem driver for Surface System Aggregator Module (SSAM). * * Copyright (C) 2022-2023 Maximilian Luz <luzmaximilian@gmail.com> */
#include <linux/bitops.h>#include <linux/hwmon.h>#include <linux/kernel.h>#include <linux/module.h>#include <linux/types.h>
#include <linux/surface_aggregator/controller.h>#include <linux/surface_aggregator/device.h>
/* -- SAM interface. -------------------------------------------------------- */
/* * Available sensors are indicated by a 16-bit bitfield, where a 1 marks the * presence of a sensor. So we have at most 16 possible sensors/channels. */#define SSAM_TMP_SENSOR_MAX_COUNT 16
/* * All names observed so far are 6 characters long, but there's only * zeros after the name, so perhaps they can be longer. This number reflects * the maximum zero-padded space observed in the returned buffer. */#define SSAM_TMP_SENSOR_NAME_LENGTH 18
struct ssam_tmp_get_name_rsp { __le16 unknown1; char unknown2; char name[SSAM_TMP_SENSOR_NAME_LENGTH];} __packed;
static_assert(sizeof(struct ssam_tmp_get_name_rsp) == 21);
SSAM_DEFINE_SYNC_REQUEST_CL_R(__ssam_tmp_get_available_sensors, __le16, { .target_category = SSAM_SSH_TC_TMP, .command_id = 0x04,});
SSAM_DEFINE_SYNC_REQUEST_MD_R(__ssam_tmp_get_temperature, __le16, { .target_category = SSAM_SSH_TC_TMP, .command_id = 0x01,});
SSAM_DEFINE_SYNC_REQUEST_MD_R(__ssam_tmp_get_name, struct ssam_tmp_get_name_rsp, { .target_category = SSAM_SSH_TC_TMP, .command_id = 0x0e,});
static int ssam_tmp_get_available_sensors(struct ssam_device *sdev, s16 *sensors){ __le16 sensors_le; int status;
status = __ssam_tmp_get_available_sensors(sdev, &sensors_le); if (status) return status;
*sensors = le16_to_cpu(sensors_le); return 0;}
static int ssam_tmp_get_temperature(struct ssam_device *sdev, u8 iid, long *temperature){ __le16 temp_le; int status;
status = __ssam_tmp_get_temperature(sdev->ctrl, sdev->uid.target, iid, &temp_le); if (status) return status;
/* Convert 1/10 °K to 1/1000 °C */ *temperature = (le16_to_cpu(temp_le) - 2731) * 100L; return 0;}
static int ssam_tmp_get_name(struct ssam_device *sdev, u8 iid, char *buf, size_t buf_len){ struct ssam_tmp_get_name_rsp name_rsp; int status;
status = __ssam_tmp_get_name(sdev->ctrl, sdev->uid.target, iid, &name_rsp); if (status) return status;
/* * This should not fail unless the name in the returned struct is not * null-terminated or someone changed something in the struct * definitions above, since our buffer and struct have the same * capacity by design. So if this fails, log an error message. Since * the more likely cause is that the returned string isn't * null-terminated, we might have received garbage (as opposed to just * an incomplete string), so also fail the function. */ status = strscpy(buf, name_rsp.name, buf_len); if (status < 0) { dev_err(&sdev->dev, "received non-null-terminated sensor name string\n"); return status; }
return 0;}
/* -- Driver.---------------------------------------------------------------- */
struct ssam_temp { struct ssam_device *sdev; s16 sensors; char names[SSAM_TMP_SENSOR_MAX_COUNT][SSAM_TMP_SENSOR_NAME_LENGTH];};
static umode_t ssam_temp_hwmon_is_visible(const void *data, enum hwmon_sensor_types type, u32 attr, int channel){ const struct ssam_temp *ssam_temp = data;
if (!(ssam_temp->sensors & BIT(channel))) return 0;
return 0444;}
static int ssam_temp_hwmon_read(struct device *dev, enum hwmon_sensor_types type, u32 attr, int channel, long *value){ const struct ssam_temp *ssam_temp = dev_get_drvdata(dev);
return ssam_tmp_get_temperature(ssam_temp->sdev, channel + 1, value);}
static int ssam_temp_hwmon_read_string(struct device *dev, enum hwmon_sensor_types type, u32 attr, int channel, const char **str){ const struct ssam_temp *ssam_temp = dev_get_drvdata(dev);
*str = ssam_temp->names[channel]; return 0;}
static const struct hwmon_channel_info * const ssam_temp_hwmon_info[] = { HWMON_CHANNEL_INFO(chip, HWMON_C_REGISTER_TZ), HWMON_CHANNEL_INFO(temp, HWMON_T_INPUT | HWMON_T_LABEL, HWMON_T_INPUT | HWMON_T_LABEL, HWMON_T_INPUT | HWMON_T_LABEL, HWMON_T_INPUT | HWMON_T_LABEL, HWMON_T_INPUT | HWMON_T_LABEL, HWMON_T_INPUT | HWMON_T_LABEL, HWMON_T_INPUT | HWMON_T_LABEL, HWMON_T_INPUT | HWMON_T_LABEL, HWMON_T_INPUT | HWMON_T_LABEL, HWMON_T_INPUT | HWMON_T_LABEL, HWMON_T_INPUT | HWMON_T_LABEL, HWMON_T_INPUT | HWMON_T_LABEL, HWMON_T_INPUT | HWMON_T_LABEL, HWMON_T_INPUT | HWMON_T_LABEL, HWMON_T_INPUT | HWMON_T_LABEL, HWMON_T_INPUT | HWMON_T_LABEL), NULL};
static const struct hwmon_ops ssam_temp_hwmon_ops = { .is_visible = ssam_temp_hwmon_is_visible, .read = ssam_temp_hwmon_read, .read_string = ssam_temp_hwmon_read_string,};
static const struct hwmon_chip_info ssam_temp_hwmon_chip_info = { .ops = &ssam_temp_hwmon_ops, .info = ssam_temp_hwmon_info,};
static int ssam_temp_probe(struct ssam_device *sdev){ struct ssam_temp *ssam_temp; struct device *hwmon_dev; s16 sensors; int channel; int status;
status = ssam_tmp_get_available_sensors(sdev, &sensors); if (status) return status;
ssam_temp = devm_kzalloc(&sdev->dev, sizeof(*ssam_temp), GFP_KERNEL); if (!ssam_temp) return -ENOMEM;
ssam_temp->sdev = sdev; ssam_temp->sensors = sensors;
/* Retrieve the name for each available sensor. */ for (channel = 0; channel < SSAM_TMP_SENSOR_MAX_COUNT; channel++) { if (!(sensors & BIT(channel))) continue;
status = ssam_tmp_get_name(sdev, channel + 1, ssam_temp->names[channel], SSAM_TMP_SENSOR_NAME_LENGTH); if (status) return status; }
hwmon_dev = devm_hwmon_device_register_with_info(&sdev->dev, "surface_thermal", ssam_temp, &ssam_temp_hwmon_chip_info, NULL); return PTR_ERR_OR_ZERO(hwmon_dev);}
static const struct ssam_device_id ssam_temp_match[] = { { SSAM_SDEV(TMP, SAM, 0x00, 0x02) }, { },};MODULE_DEVICE_TABLE(ssam, ssam_temp_match);
static struct ssam_device_driver ssam_temp = { .probe = ssam_temp_probe, .match_table = ssam_temp_match, .driver = { .name = "surface_temp", .probe_type = PROBE_PREFER_ASYNCHRONOUS, },};module_ssam_device_driver(ssam_temp);
MODULE_AUTHOR("Maximilian Luz <luzmaximilian@gmail.com>");MODULE_DESCRIPTION("Thermal sensor subsystem driver for Surface System Aggregator Module");MODULE_LICENSE("GPL");