linux/drivers/hwmon/occ/sysfs.c
Eddie James 849b0156d9 hwmon: (occ) Delay hwmon registration until user request
Instead of registering the hwmon device at probe time, use the
existing "occ_active" sysfs file to control when the driver polls
the OCC for sensor data and registers with hwmon. The reason for
this change is that the SBE, which is the device by which the
driver communicates with the OCC, cannot handle communications
during certain system state transitions, resulting in
unrecoverable system errors.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
Link: https://lore.kernel.org/r/20220427140443.11428-1-eajames@linux.ibm.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2022-05-20 10:57:06 -07:00

258 lines
7.2 KiB
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);
}