1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Qualcomm Technologies HIDMA Management SYS interface
4  *
5  * Copyright (c) 2015, The Linux Foundation. All rights reserved.
6  */
7 
8 #include <linux/sysfs.h>
9 #include <linux/platform_device.h>
10 
11 #include "hidma_mgmt.h"
12 
13 struct hidma_chan_attr {
14 	struct hidma_mgmt_dev *mdev;
15 	int index;
16 	struct kobj_attribute attr;
17 };
18 
19 struct hidma_mgmt_fileinfo {
20 	char *name;
21 	int mode;
22 	int (*get)(struct hidma_mgmt_dev *mdev);
23 	int (*set)(struct hidma_mgmt_dev *mdev, u64 val);
24 };
25 
26 #define IMPLEMENT_GETSET(name)					\
27 static int get_##name(struct hidma_mgmt_dev *mdev)		\
28 {								\
29 	return mdev->name;					\
30 }								\
31 static int set_##name(struct hidma_mgmt_dev *mdev, u64 val)	\
32 {								\
33 	u64 tmp;						\
34 	int rc;							\
35 								\
36 	tmp = mdev->name;					\
37 	mdev->name = val;					\
38 	rc = hidma_mgmt_setup(mdev);				\
39 	if (rc)							\
40 		mdev->name = tmp;				\
41 	return rc;						\
42 }
43 
44 #define DECLARE_ATTRIBUTE(name, mode)				\
45 	{#name, mode, get_##name, set_##name}
46 
47 IMPLEMENT_GETSET(hw_version_major)
48 IMPLEMENT_GETSET(hw_version_minor)
49 IMPLEMENT_GETSET(max_wr_xactions)
50 IMPLEMENT_GETSET(max_rd_xactions)
51 IMPLEMENT_GETSET(max_write_request)
52 IMPLEMENT_GETSET(max_read_request)
53 IMPLEMENT_GETSET(dma_channels)
54 IMPLEMENT_GETSET(chreset_timeout_cycles)
55 
56 static int set_priority(struct hidma_mgmt_dev *mdev, unsigned int i, u64 val)
57 {
58 	u64 tmp;
59 	int rc;
60 
61 	if (i >= mdev->dma_channels)
62 		return -EINVAL;
63 
64 	tmp = mdev->priority[i];
65 	mdev->priority[i] = val;
66 	rc = hidma_mgmt_setup(mdev);
67 	if (rc)
68 		mdev->priority[i] = tmp;
69 	return rc;
70 }
71 
72 static int set_weight(struct hidma_mgmt_dev *mdev, unsigned int i, u64 val)
73 {
74 	u64 tmp;
75 	int rc;
76 
77 	if (i >= mdev->dma_channels)
78 		return -EINVAL;
79 
80 	tmp = mdev->weight[i];
81 	mdev->weight[i] = val;
82 	rc = hidma_mgmt_setup(mdev);
83 	if (rc)
84 		mdev->weight[i] = tmp;
85 	return rc;
86 }
87 
88 static struct hidma_mgmt_fileinfo hidma_mgmt_files[] = {
89 	DECLARE_ATTRIBUTE(hw_version_major, S_IRUGO),
90 	DECLARE_ATTRIBUTE(hw_version_minor, S_IRUGO),
91 	DECLARE_ATTRIBUTE(dma_channels, S_IRUGO),
92 	DECLARE_ATTRIBUTE(chreset_timeout_cycles, S_IRUGO),
93 	DECLARE_ATTRIBUTE(max_wr_xactions, S_IRUGO),
94 	DECLARE_ATTRIBUTE(max_rd_xactions, S_IRUGO),
95 	DECLARE_ATTRIBUTE(max_write_request, S_IRUGO),
96 	DECLARE_ATTRIBUTE(max_read_request, S_IRUGO),
97 };
98 
99 static ssize_t show_values(struct device *dev, struct device_attribute *attr,
100 			   char *buf)
101 {
102 	struct hidma_mgmt_dev *mdev = dev_get_drvdata(dev);
103 	unsigned int i;
104 
105 	buf[0] = 0;
106 
107 	for (i = 0; i < ARRAY_SIZE(hidma_mgmt_files); i++) {
108 		if (strcmp(attr->attr.name, hidma_mgmt_files[i].name) == 0) {
109 			sprintf(buf, "%d\n", hidma_mgmt_files[i].get(mdev));
110 			break;
111 		}
112 	}
113 	return strlen(buf);
114 }
115 
116 static ssize_t set_values(struct device *dev, struct device_attribute *attr,
117 			  const char *buf, size_t count)
118 {
119 	struct hidma_mgmt_dev *mdev = dev_get_drvdata(dev);
120 	unsigned long tmp;
121 	unsigned int i;
122 	int rc;
123 
124 	rc = kstrtoul(buf, 0, &tmp);
125 	if (rc)
126 		return rc;
127 
128 	for (i = 0; i < ARRAY_SIZE(hidma_mgmt_files); i++) {
129 		if (strcmp(attr->attr.name, hidma_mgmt_files[i].name) == 0) {
130 			rc = hidma_mgmt_files[i].set(mdev, tmp);
131 			if (rc)
132 				return rc;
133 
134 			break;
135 		}
136 	}
137 	return count;
138 }
139 
140 static ssize_t show_values_channel(struct kobject *kobj,
141 				   struct kobj_attribute *attr, char *buf)
142 {
143 	struct hidma_chan_attr *chattr;
144 	struct hidma_mgmt_dev *mdev;
145 
146 	buf[0] = 0;
147 	chattr = container_of(attr, struct hidma_chan_attr, attr);
148 	mdev = chattr->mdev;
149 	if (strcmp(attr->attr.name, "priority") == 0)
150 		sprintf(buf, "%d\n", mdev->priority[chattr->index]);
151 	else if (strcmp(attr->attr.name, "weight") == 0)
152 		sprintf(buf, "%d\n", mdev->weight[chattr->index]);
153 
154 	return strlen(buf);
155 }
156 
157 static ssize_t set_values_channel(struct kobject *kobj,
158 				  struct kobj_attribute *attr, const char *buf,
159 				  size_t count)
160 {
161 	struct hidma_chan_attr *chattr;
162 	struct hidma_mgmt_dev *mdev;
163 	unsigned long tmp;
164 	int rc;
165 
166 	chattr = container_of(attr, struct hidma_chan_attr, attr);
167 	mdev = chattr->mdev;
168 
169 	rc = kstrtoul(buf, 0, &tmp);
170 	if (rc)
171 		return rc;
172 
173 	if (strcmp(attr->attr.name, "priority") == 0) {
174 		rc = set_priority(mdev, chattr->index, tmp);
175 		if (rc)
176 			return rc;
177 	} else if (strcmp(attr->attr.name, "weight") == 0) {
178 		rc = set_weight(mdev, chattr->index, tmp);
179 		if (rc)
180 			return rc;
181 	}
182 	return count;
183 }
184 
185 static int create_sysfs_entry(struct hidma_mgmt_dev *dev, char *name, int mode)
186 {
187 	struct device_attribute *attrs;
188 	char *name_copy;
189 
190 	attrs = devm_kmalloc(&dev->pdev->dev,
191 			     sizeof(struct device_attribute), GFP_KERNEL);
192 	if (!attrs)
193 		return -ENOMEM;
194 
195 	name_copy = devm_kstrdup(&dev->pdev->dev, name, GFP_KERNEL);
196 	if (!name_copy)
197 		return -ENOMEM;
198 
199 	attrs->attr.name = name_copy;
200 	attrs->attr.mode = mode;
201 	attrs->show = show_values;
202 	attrs->store = set_values;
203 	sysfs_attr_init(&attrs->attr);
204 
205 	return device_create_file(&dev->pdev->dev, attrs);
206 }
207 
208 static int create_sysfs_entry_channel(struct hidma_mgmt_dev *mdev, char *name,
209 				      int mode, int index,
210 				      struct kobject *parent)
211 {
212 	struct hidma_chan_attr *chattr;
213 	char *name_copy;
214 
215 	chattr = devm_kmalloc(&mdev->pdev->dev, sizeof(*chattr), GFP_KERNEL);
216 	if (!chattr)
217 		return -ENOMEM;
218 
219 	name_copy = devm_kstrdup(&mdev->pdev->dev, name, GFP_KERNEL);
220 	if (!name_copy)
221 		return -ENOMEM;
222 
223 	chattr->mdev = mdev;
224 	chattr->index = index;
225 	chattr->attr.attr.name = name_copy;
226 	chattr->attr.attr.mode = mode;
227 	chattr->attr.show = show_values_channel;
228 	chattr->attr.store = set_values_channel;
229 	sysfs_attr_init(&chattr->attr.attr);
230 
231 	return sysfs_create_file(parent, &chattr->attr.attr);
232 }
233 
234 int hidma_mgmt_init_sys(struct hidma_mgmt_dev *mdev)
235 {
236 	unsigned int i;
237 	int rc;
238 	int required;
239 	struct kobject *chanops;
240 
241 	required = sizeof(*mdev->chroots) * mdev->dma_channels;
242 	mdev->chroots = devm_kmalloc(&mdev->pdev->dev, required, GFP_KERNEL);
243 	if (!mdev->chroots)
244 		return -ENOMEM;
245 
246 	chanops = kobject_create_and_add("chanops", &mdev->pdev->dev.kobj);
247 	if (!chanops)
248 		return -ENOMEM;
249 
250 	/* create each channel directory here */
251 	for (i = 0; i < mdev->dma_channels; i++) {
252 		char name[20];
253 
254 		snprintf(name, sizeof(name), "chan%d", i);
255 		mdev->chroots[i] = kobject_create_and_add(name, chanops);
256 		if (!mdev->chroots[i])
257 			return -ENOMEM;
258 	}
259 
260 	/* populate common parameters */
261 	for (i = 0; i < ARRAY_SIZE(hidma_mgmt_files); i++) {
262 		rc = create_sysfs_entry(mdev, hidma_mgmt_files[i].name,
263 					hidma_mgmt_files[i].mode);
264 		if (rc)
265 			return rc;
266 	}
267 
268 	/* populate parameters that are per channel */
269 	for (i = 0; i < mdev->dma_channels; i++) {
270 		rc = create_sysfs_entry_channel(mdev, "priority",
271 						(S_IRUGO | S_IWUGO), i,
272 						mdev->chroots[i]);
273 		if (rc)
274 			return rc;
275 
276 		rc = create_sysfs_entry_channel(mdev, "weight",
277 						(S_IRUGO | S_IWUGO), i,
278 						mdev->chroots[i]);
279 		if (rc)
280 			return rc;
281 	}
282 
283 	return 0;
284 }
285 EXPORT_SYMBOL_GPL(hidma_mgmt_init_sys);
286