root/drivers/hwmon/occ/sysfs.c
// SPDX-License-Identifier: GPL-2.0+
// Copyright IBM Corp 2019

#include <linux/bitops.h>
#include <linux/device.h>
#include <linux/export.h>
#include <linux/hwmon-sysfs.h>
#include <linux/kernel.h>
#include <linux/kstrtox.h>
#include <linux/sysfs.h>

#include "common.h"

/* OCC status register */
#define OCC_STAT_MASTER                 BIT(7)

/* OCC extended status register */
#define OCC_EXT_STAT_DVFS_OT            BIT(7)
#define OCC_EXT_STAT_DVFS_POWER         BIT(6)
#define OCC_EXT_STAT_MEM_THROTTLE       BIT(5)
#define OCC_EXT_STAT_QUICK_DROP         BIT(4)
#define OCC_EXT_STAT_DVFS_VDD           BIT(3)
#define OCC_EXT_STAT_GPU_THROTTLE       GENMASK(2, 0)

static ssize_t occ_active_store(struct device *dev,
                                struct device_attribute *attr,
                                const char *buf, size_t count)
{
        int rc;
        bool active;
        struct occ *occ = dev_get_drvdata(dev);

        rc = kstrtobool(buf, &active);
        if (rc)
                return rc;

        rc = occ_active(occ, active);
        if (rc)
                return rc;

        return count;
}

static ssize_t occ_sysfs_show(struct device *dev,
                              struct device_attribute *attr, char *buf)
{
        int rc;
        int val = 0;
        struct occ *occ = dev_get_drvdata(dev);
        struct occ_poll_response_header *header;
        struct sensor_device_attribute *sattr = to_sensor_dev_attr(attr);

        if (occ->active) {
                rc = occ_update_response(occ);
                if (rc)
                        return rc;

                header = (struct occ_poll_response_header *)occ->resp.data;

                switch (sattr->index) {
                case 0:
                        val = !!(header->status & OCC_STAT_MASTER);
                        break;
                case 1:
                        val = 1;
                        break;
                case 2:
                        val = !!(header->ext_status & OCC_EXT_STAT_DVFS_OT);
                        break;
                case 3:
                        val = !!(header->ext_status & OCC_EXT_STAT_DVFS_POWER);
                        break;
                case 4:
                        val = !!(header->ext_status &
                                 OCC_EXT_STAT_MEM_THROTTLE);
                        break;
                case 5:
                        val = !!(header->ext_status & OCC_EXT_STAT_QUICK_DROP);
                        break;
                case 6:
                        val = header->occ_state;
                        break;
                case 7:
                        if (header->status & OCC_STAT_MASTER)
                                val = hweight8(header->occs_present);
                        else
                                val = 1;
                        break;
                case 8:
                        val = header->ips_status;
                        break;
                case 9:
                        val = header->mode;
                        break;
                case 10:
                        val = !!(header->ext_status & OCC_EXT_STAT_DVFS_VDD);
                        break;
                case 11:
                        val = header->ext_status & OCC_EXT_STAT_GPU_THROTTLE;
                        break;
                default:
                        return -EINVAL;
                }
        } else {
                if (sattr->index == 1)
                        val = 0;
                else if (sattr->index <= 11)
                        val = -ENODATA;
                else
                        return -EINVAL;
        }

        return sysfs_emit(buf, "%d\n", val);
}

static ssize_t occ_error_show(struct device *dev,
                              struct device_attribute *attr, char *buf)
{
        struct occ *occ = dev_get_drvdata(dev);

        occ_update_response(occ);

        return sysfs_emit(buf, "%d\n", occ->error);
}

static SENSOR_DEVICE_ATTR(occ_master, 0444, occ_sysfs_show, NULL, 0);
static SENSOR_DEVICE_ATTR(occ_active, 0644, occ_sysfs_show, occ_active_store,
                          1);
static SENSOR_DEVICE_ATTR(occ_dvfs_overtemp, 0444, occ_sysfs_show, NULL, 2);
static SENSOR_DEVICE_ATTR(occ_dvfs_power, 0444, occ_sysfs_show, NULL, 3);
static SENSOR_DEVICE_ATTR(occ_mem_throttle, 0444, occ_sysfs_show, NULL, 4);
static SENSOR_DEVICE_ATTR(occ_quick_pwr_drop, 0444, occ_sysfs_show, NULL, 5);
static SENSOR_DEVICE_ATTR(occ_state, 0444, occ_sysfs_show, NULL, 6);
static SENSOR_DEVICE_ATTR(occs_present, 0444, occ_sysfs_show, NULL, 7);
static SENSOR_DEVICE_ATTR(occ_ips_status, 0444, occ_sysfs_show, NULL, 8);
static SENSOR_DEVICE_ATTR(occ_mode, 0444, occ_sysfs_show, NULL, 9);
static SENSOR_DEVICE_ATTR(occ_dvfs_vdd, 0444, occ_sysfs_show, NULL, 10);
static SENSOR_DEVICE_ATTR(occ_gpu_throttle, 0444, occ_sysfs_show, NULL, 11);
static DEVICE_ATTR_RO(occ_error);

static struct attribute *occ_attributes[] = {
        &sensor_dev_attr_occ_master.dev_attr.attr,
        &sensor_dev_attr_occ_active.dev_attr.attr,
        &sensor_dev_attr_occ_dvfs_overtemp.dev_attr.attr,
        &sensor_dev_attr_occ_dvfs_power.dev_attr.attr,
        &sensor_dev_attr_occ_mem_throttle.dev_attr.attr,
        &sensor_dev_attr_occ_quick_pwr_drop.dev_attr.attr,
        &sensor_dev_attr_occ_state.dev_attr.attr,
        &sensor_dev_attr_occs_present.dev_attr.attr,
        &sensor_dev_attr_occ_ips_status.dev_attr.attr,
        &sensor_dev_attr_occ_mode.dev_attr.attr,
        &sensor_dev_attr_occ_dvfs_vdd.dev_attr.attr,
        &sensor_dev_attr_occ_gpu_throttle.dev_attr.attr,
        &dev_attr_occ_error.attr,
        NULL
};

static const struct attribute_group occ_sysfs = {
        .attrs = occ_attributes,
};

void occ_sysfs_poll_done(struct occ *occ)
{
        const char *name;
        struct occ_poll_response_header *header =
                (struct occ_poll_response_header *)occ->resp.data;

        /*
         * On the first poll response, we haven't yet created the sysfs
         * attributes, so don't make any notify calls.
         */
        if (!occ->active)
                goto done;

        if ((header->status & OCC_STAT_MASTER) !=
            (occ->prev_stat & OCC_STAT_MASTER)) {
                name = sensor_dev_attr_occ_master.dev_attr.attr.name;
                sysfs_notify(&occ->bus_dev->kobj, NULL, name);
        }

        if ((header->ext_status & OCC_EXT_STAT_DVFS_OT) !=
            (occ->prev_ext_stat & OCC_EXT_STAT_DVFS_OT)) {
                name = sensor_dev_attr_occ_dvfs_overtemp.dev_attr.attr.name;
                sysfs_notify(&occ->bus_dev->kobj, NULL, name);
        }

        if ((header->ext_status & OCC_EXT_STAT_DVFS_POWER) !=
            (occ->prev_ext_stat & OCC_EXT_STAT_DVFS_POWER)) {
                name = sensor_dev_attr_occ_dvfs_power.dev_attr.attr.name;
                sysfs_notify(&occ->bus_dev->kobj, NULL, name);
        }

        if ((header->ext_status & OCC_EXT_STAT_MEM_THROTTLE) !=
            (occ->prev_ext_stat & OCC_EXT_STAT_MEM_THROTTLE)) {
                name = sensor_dev_attr_occ_mem_throttle.dev_attr.attr.name;
                sysfs_notify(&occ->bus_dev->kobj, NULL, name);
        }

        if ((header->ext_status & OCC_EXT_STAT_QUICK_DROP) !=
            (occ->prev_ext_stat & OCC_EXT_STAT_QUICK_DROP)) {
                name = sensor_dev_attr_occ_quick_pwr_drop.dev_attr.attr.name;
                sysfs_notify(&occ->bus_dev->kobj, NULL, name);
        }

        if ((header->ext_status & OCC_EXT_STAT_DVFS_VDD) !=
            (occ->prev_ext_stat & OCC_EXT_STAT_DVFS_VDD)) {
                name = sensor_dev_attr_occ_dvfs_vdd.dev_attr.attr.name;
                sysfs_notify(&occ->bus_dev->kobj, NULL, name);
        }

        if ((header->ext_status & OCC_EXT_STAT_GPU_THROTTLE) !=
            (occ->prev_ext_stat & OCC_EXT_STAT_GPU_THROTTLE)) {
                name = sensor_dev_attr_occ_gpu_throttle.dev_attr.attr.name;
                sysfs_notify(&occ->bus_dev->kobj, NULL, name);
        }

        if ((header->status & OCC_STAT_MASTER) &&
            header->occs_present != occ->prev_occs_present) {
                name = sensor_dev_attr_occs_present.dev_attr.attr.name;
                sysfs_notify(&occ->bus_dev->kobj, NULL, name);
        }

        if (header->ips_status != occ->prev_ips_status) {
                name = sensor_dev_attr_occ_ips_status.dev_attr.attr.name;
                sysfs_notify(&occ->bus_dev->kobj, NULL, name);
        }

        if (header->mode != occ->prev_mode) {
                name = sensor_dev_attr_occ_mode.dev_attr.attr.name;
                sysfs_notify(&occ->bus_dev->kobj, NULL, name);
        }

        if (occ->error && occ->error != occ->prev_error) {
                name = dev_attr_occ_error.attr.name;
                sysfs_notify(&occ->bus_dev->kobj, NULL, name);
        }

        /* no notifications for OCC state; doesn't indicate error condition */

done:
        occ->prev_error = occ->error;
        occ->prev_stat = header->status;
        occ->prev_ext_stat = header->ext_status;
        occ->prev_occs_present = header->occs_present;
        occ->prev_ips_status = header->ips_status;
        occ->prev_mode = header->mode;
}

int occ_setup_sysfs(struct occ *occ)
{
        return sysfs_create_group(&occ->bus_dev->kobj, &occ_sysfs);
}

void occ_shutdown_sysfs(struct occ *occ)
{
        sysfs_remove_group(&occ->bus_dev->kobj, &occ_sysfs);
}