1 /*
2  * Qualcomm Technologies HIDMA Management SYS interface
3  *
4  * Copyright (c) 2015, The Linux Foundation. All rights reserved.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 and
8  * only version 2 as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  */
15 
16 #include <linux/sysfs.h>
17 #include <linux/platform_device.h>
18 
19 #include "hidma_mgmt.h"
20 
21 struct hidma_chan_attr {
22 	struct hidma_mgmt_dev *mdev;
23 	int index;
24 	struct kobj_attribute attr;
25 };
26 
27 struct hidma_mgmt_fileinfo {
28 	char *name;
29 	int mode;
30 	int (*get)(struct hidma_mgmt_dev *mdev);
31 	int (*set)(struct hidma_mgmt_dev *mdev, u64 val);
32 };
33 
34 #define IMPLEMENT_GETSET(name)					\
35 static int get_##name(struct hidma_mgmt_dev *mdev)		\
36 {								\
37 	return mdev->name;					\
38 }								\
39 static int set_##name(struct hidma_mgmt_dev *mdev, u64 val)	\
40 {								\
41 	u64 tmp;						\
42 	int rc;							\
43 								\
44 	tmp = mdev->name;					\
45 	mdev->name = val;					\
46 	rc = hidma_mgmt_setup(mdev);				\
47 	if (rc)							\
48 		mdev->name = tmp;				\
49 	return rc;						\
50 }
51 
52 #define DECLARE_ATTRIBUTE(name, mode)				\
53 	{#name, mode, get_##name, set_##name}
54 
55 IMPLEMENT_GETSET(hw_version_major)
56 IMPLEMENT_GETSET(hw_version_minor)
57 IMPLEMENT_GETSET(max_wr_xactions)
58 IMPLEMENT_GETSET(max_rd_xactions)
59 IMPLEMENT_GETSET(max_write_request)
60 IMPLEMENT_GETSET(max_read_request)
61 IMPLEMENT_GETSET(dma_channels)
62 IMPLEMENT_GETSET(chreset_timeout_cycles)
63 
64 static int set_priority(struct hidma_mgmt_dev *mdev, unsigned int i, u64 val)
65 {
66 	u64 tmp;
67 	int rc;
68 
69 	if (i >= mdev->dma_channels)
70 		return -EINVAL;
71 
72 	tmp = mdev->priority[i];
73 	mdev->priority[i] = val;
74 	rc = hidma_mgmt_setup(mdev);
75 	if (rc)
76 		mdev->priority[i] = tmp;
77 	return rc;
78 }
79 
80 static int set_weight(struct hidma_mgmt_dev *mdev, unsigned int i, u64 val)
81 {
82 	u64 tmp;
83 	int rc;
84 
85 	if (i >= mdev->dma_channels)
86 		return -EINVAL;
87 
88 	tmp = mdev->weight[i];
89 	mdev->weight[i] = val;
90 	rc = hidma_mgmt_setup(mdev);
91 	if (rc)
92 		mdev->weight[i] = tmp;
93 	return rc;
94 }
95 
96 static struct hidma_mgmt_fileinfo hidma_mgmt_files[] = {
97 	DECLARE_ATTRIBUTE(hw_version_major, S_IRUGO),
98 	DECLARE_ATTRIBUTE(hw_version_minor, S_IRUGO),
99 	DECLARE_ATTRIBUTE(dma_channels, S_IRUGO),
100 	DECLARE_ATTRIBUTE(chreset_timeout_cycles, S_IRUGO),
101 	DECLARE_ATTRIBUTE(max_wr_xactions, S_IRUGO),
102 	DECLARE_ATTRIBUTE(max_rd_xactions, S_IRUGO),
103 	DECLARE_ATTRIBUTE(max_write_request, S_IRUGO),
104 	DECLARE_ATTRIBUTE(max_read_request, S_IRUGO),
105 };
106 
107 static ssize_t show_values(struct device *dev, struct device_attribute *attr,
108 			   char *buf)
109 {
110 	struct hidma_mgmt_dev *mdev = dev_get_drvdata(dev);
111 	unsigned int i;
112 
113 	buf[0] = 0;
114 
115 	for (i = 0; i < ARRAY_SIZE(hidma_mgmt_files); i++) {
116 		if (strcmp(attr->attr.name, hidma_mgmt_files[i].name) == 0) {
117 			sprintf(buf, "%d\n", hidma_mgmt_files[i].get(mdev));
118 			break;
119 		}
120 	}
121 	return strlen(buf);
122 }
123 
124 static ssize_t set_values(struct device *dev, struct device_attribute *attr,
125 			  const char *buf, size_t count)
126 {
127 	struct hidma_mgmt_dev *mdev = dev_get_drvdata(dev);
128 	unsigned long tmp;
129 	unsigned int i;
130 	int rc;
131 
132 	rc = kstrtoul(buf, 0, &tmp);
133 	if (rc)
134 		return rc;
135 
136 	for (i = 0; i < ARRAY_SIZE(hidma_mgmt_files); i++) {
137 		if (strcmp(attr->attr.name, hidma_mgmt_files[i].name) == 0) {
138 			rc = hidma_mgmt_files[i].set(mdev, tmp);
139 			if (rc)
140 				return rc;
141 
142 			break;
143 		}
144 	}
145 	return count;
146 }
147 
148 static ssize_t show_values_channel(struct kobject *kobj,
149 				   struct kobj_attribute *attr, char *buf)
150 {
151 	struct hidma_chan_attr *chattr;
152 	struct hidma_mgmt_dev *mdev;
153 
154 	buf[0] = 0;
155 	chattr = container_of(attr, struct hidma_chan_attr, attr);
156 	mdev = chattr->mdev;
157 	if (strcmp(attr->attr.name, "priority") == 0)
158 		sprintf(buf, "%d\n", mdev->priority[chattr->index]);
159 	else if (strcmp(attr->attr.name, "weight") == 0)
160 		sprintf(buf, "%d\n", mdev->weight[chattr->index]);
161 
162 	return strlen(buf);
163 }
164 
165 static ssize_t set_values_channel(struct kobject *kobj,
166 				  struct kobj_attribute *attr, const char *buf,
167 				  size_t count)
168 {
169 	struct hidma_chan_attr *chattr;
170 	struct hidma_mgmt_dev *mdev;
171 	unsigned long tmp;
172 	int rc;
173 
174 	chattr = container_of(attr, struct hidma_chan_attr, attr);
175 	mdev = chattr->mdev;
176 
177 	rc = kstrtoul(buf, 0, &tmp);
178 	if (rc)
179 		return rc;
180 
181 	if (strcmp(attr->attr.name, "priority") == 0) {
182 		rc = set_priority(mdev, chattr->index, tmp);
183 		if (rc)
184 			return rc;
185 	} else if (strcmp(attr->attr.name, "weight") == 0) {
186 		rc = set_weight(mdev, chattr->index, tmp);
187 		if (rc)
188 			return rc;
189 	}
190 	return count;
191 }
192 
193 static int create_sysfs_entry(struct hidma_mgmt_dev *dev, char *name, int mode)
194 {
195 	struct device_attribute *attrs;
196 	char *name_copy;
197 
198 	attrs = devm_kmalloc(&dev->pdev->dev,
199 			     sizeof(struct device_attribute), GFP_KERNEL);
200 	if (!attrs)
201 		return -ENOMEM;
202 
203 	name_copy = devm_kstrdup(&dev->pdev->dev, name, GFP_KERNEL);
204 	if (!name_copy)
205 		return -ENOMEM;
206 
207 	attrs->attr.name = name_copy;
208 	attrs->attr.mode = mode;
209 	attrs->show = show_values;
210 	attrs->store = set_values;
211 	sysfs_attr_init(&attrs->attr);
212 
213 	return device_create_file(&dev->pdev->dev, attrs);
214 }
215 
216 static int create_sysfs_entry_channel(struct hidma_mgmt_dev *mdev, char *name,
217 				      int mode, int index,
218 				      struct kobject *parent)
219 {
220 	struct hidma_chan_attr *chattr;
221 	char *name_copy;
222 
223 	chattr = devm_kmalloc(&mdev->pdev->dev, sizeof(*chattr), GFP_KERNEL);
224 	if (!chattr)
225 		return -ENOMEM;
226 
227 	name_copy = devm_kstrdup(&mdev->pdev->dev, name, GFP_KERNEL);
228 	if (!name_copy)
229 		return -ENOMEM;
230 
231 	chattr->mdev = mdev;
232 	chattr->index = index;
233 	chattr->attr.attr.name = name_copy;
234 	chattr->attr.attr.mode = mode;
235 	chattr->attr.show = show_values_channel;
236 	chattr->attr.store = set_values_channel;
237 	sysfs_attr_init(&chattr->attr.attr);
238 
239 	return sysfs_create_file(parent, &chattr->attr.attr);
240 }
241 
242 int hidma_mgmt_init_sys(struct hidma_mgmt_dev *mdev)
243 {
244 	unsigned int i;
245 	int rc;
246 	int required;
247 	struct kobject *chanops;
248 
249 	required = sizeof(*mdev->chroots) * mdev->dma_channels;
250 	mdev->chroots = devm_kmalloc(&mdev->pdev->dev, required, GFP_KERNEL);
251 	if (!mdev->chroots)
252 		return -ENOMEM;
253 
254 	chanops = kobject_create_and_add("chanops", &mdev->pdev->dev.kobj);
255 	if (!chanops)
256 		return -ENOMEM;
257 
258 	/* create each channel directory here */
259 	for (i = 0; i < mdev->dma_channels; i++) {
260 		char name[20];
261 
262 		snprintf(name, sizeof(name), "chan%d", i);
263 		mdev->chroots[i] = kobject_create_and_add(name, chanops);
264 		if (!mdev->chroots[i])
265 			return -ENOMEM;
266 	}
267 
268 	/* populate common parameters */
269 	for (i = 0; i < ARRAY_SIZE(hidma_mgmt_files); i++) {
270 		rc = create_sysfs_entry(mdev, hidma_mgmt_files[i].name,
271 					hidma_mgmt_files[i].mode);
272 		if (rc)
273 			return rc;
274 	}
275 
276 	/* populate parameters that are per channel */
277 	for (i = 0; i < mdev->dma_channels; i++) {
278 		rc = create_sysfs_entry_channel(mdev, "priority",
279 						(S_IRUGO | S_IWUGO), i,
280 						mdev->chroots[i]);
281 		if (rc)
282 			return rc;
283 
284 		rc = create_sysfs_entry_channel(mdev, "weight",
285 						(S_IRUGO | S_IWUGO), i,
286 						mdev->chroots[i]);
287 		if (rc)
288 			return rc;
289 	}
290 
291 	return 0;
292 }
293 EXPORT_SYMBOL_GPL(hidma_mgmt_init_sys);
294