qaic_sysfs.c

  1// SPDX-License-Identifier: GPL-2.0-only
  2
  3/* Copyright (c) 2020-2025, The Linux Foundation. All rights reserved. */
  4
  5#include <drm/drm_file.h>
  6#include <drm/drm_managed.h>
  7#include <linux/device.h>
  8#include <linux/kernel.h>
  9#include <linux/kobject.h>
 10#include <linux/mutex.h>
 11#include <linux/sysfs.h>
 12
 13#include "qaic.h"
 14
 15#define NAME_LEN		14
 16
 17struct dbc_attribute {
 18	struct device_attribute dev_attr;
 19	u32 dbc_id;
 20	char name[NAME_LEN];
 21};
 22
 23static ssize_t dbc_state_show(struct device *dev, struct device_attribute *a, char *buf)
 24{
 25	struct dbc_attribute *dbc_attr = container_of(a, struct dbc_attribute, dev_attr);
 26	struct drm_minor *minor = dev_get_drvdata(dev);
 27	struct qaic_device *qdev;
 28
 29	qdev = to_qaic_device(minor->dev);
 30	return sysfs_emit(buf, "%d\n", qdev->dbc[dbc_attr->dbc_id].state);
 31}
 32
 33void set_dbc_state(struct qaic_device *qdev, u32 dbc_id, unsigned int state)
 34{
 35	struct device *kdev = to_accel_kdev(qdev->qddev);
 36	char *envp[3] = {};
 37	char state_str[16];
 38	char id_str[12];
 39
 40	envp[0] = id_str;
 41	envp[1] = state_str;
 42
 43	if (state >= DBC_STATE_MAX)
 44		return;
 45	if (dbc_id >= qdev->num_dbc)
 46		return;
 47	if (state == qdev->dbc[dbc_id].state)
 48		return;
 49
 50	scnprintf(id_str, ARRAY_SIZE(id_str), "DBC_ID=%d", dbc_id);
 51	scnprintf(state_str, ARRAY_SIZE(state_str), "DBC_STATE=%d", state);
 52
 53	qdev->dbc[dbc_id].state = state;
 54	kobject_uevent_env(&kdev->kobj, KOBJ_CHANGE, envp);
 55}
 56
 57int qaic_sysfs_init(struct qaic_drm_device *qddev)
 58{
 59	struct device *kdev = to_accel_kdev(qddev);
 60	struct drm_device *drm = to_drm(qddev);
 61	u32 num_dbc = qddev->qdev->num_dbc;
 62	struct dbc_attribute *dbc_attrs;
 63	int i, ret;
 64
 65	dbc_attrs = drmm_kcalloc(drm, num_dbc, sizeof(*dbc_attrs), GFP_KERNEL);
 66	if (!dbc_attrs)
 67		return -ENOMEM;
 68
 69	for (i = 0; i < num_dbc; ++i) {
 70		struct dbc_attribute *dbc_attr = &dbc_attrs[i];
 71
 72		sysfs_attr_init(&dbc_attr->dev_attr.attr);
 73		dbc_attr->dbc_id = i;
 74		scnprintf(dbc_attr->name, NAME_LEN, "dbc%d_state", i);
 75		dbc_attr->dev_attr.attr.name = dbc_attr->name;
 76		dbc_attr->dev_attr.attr.mode = 0444;
 77		dbc_attr->dev_attr.show = dbc_state_show;
 78		ret = sysfs_create_file(&kdev->kobj, &dbc_attr->dev_attr.attr);
 79		if (ret) {
 80			int j;
 81
 82			for (j = 0; j < i; ++j) {
 83				dbc_attr = &dbc_attrs[j];
 84				sysfs_remove_file(&kdev->kobj, &dbc_attr->dev_attr.attr);
 85			}
 86			drmm_kfree(drm, dbc_attrs);
 87			return ret;
 88		}
 89	}
 90
 91	qddev->sysfs_attrs = dbc_attrs;
 92	return 0;
 93}
 94
 95void qaic_sysfs_remove(struct qaic_drm_device *qddev)
 96{
 97	struct dbc_attribute *dbc_attrs = qddev->sysfs_attrs;
 98	struct device *kdev = to_accel_kdev(qddev);
 99	u32 num_dbc = qddev->qdev->num_dbc;
100	int i;
101
102	if (!dbc_attrs)
103		return;
104
105	qddev->sysfs_attrs = NULL;
106	for (i = 0; i < num_dbc; ++i)
107		sysfs_remove_file(&kdev->kobj, &dbc_attrs[i].dev_attr.attr);
108	drmm_kfree(to_drm(qddev), dbc_attrs);
109}