xref: /linux/sound/soc/codecs/sigmadsp.c (revision 3932b9ca55b0be314a36d3e84faff3e823c081f5)
1 /*
2  * Load Analog Devices SigmaStudio firmware files
3  *
4  * Copyright 2009-2011 Analog Devices Inc.
5  *
6  * Licensed under the GPL-2 or later.
7  */
8 
9 #include <linux/crc32.h>
10 #include <linux/delay.h>
11 #include <linux/firmware.h>
12 #include <linux/kernel.h>
13 #include <linux/i2c.h>
14 #include <linux/regmap.h>
15 #include <linux/module.h>
16 
17 #include "sigmadsp.h"
18 
19 #define SIGMA_MAGIC "ADISIGM"
20 
21 struct sigma_firmware_header {
22 	unsigned char magic[7];
23 	u8 version;
24 	__le32 crc;
25 } __packed;
26 
27 enum {
28 	SIGMA_ACTION_WRITEXBYTES = 0,
29 	SIGMA_ACTION_WRITESINGLE,
30 	SIGMA_ACTION_WRITESAFELOAD,
31 	SIGMA_ACTION_DELAY,
32 	SIGMA_ACTION_PLLWAIT,
33 	SIGMA_ACTION_NOOP,
34 	SIGMA_ACTION_END,
35 };
36 
37 static inline u32 sigma_action_len(struct sigma_action *sa)
38 {
39 	return (sa->len_hi << 16) | le16_to_cpu(sa->len);
40 }
41 
42 static size_t sigma_action_size(struct sigma_action *sa)
43 {
44 	size_t payload = 0;
45 
46 	switch (sa->instr) {
47 	case SIGMA_ACTION_WRITEXBYTES:
48 	case SIGMA_ACTION_WRITESINGLE:
49 	case SIGMA_ACTION_WRITESAFELOAD:
50 		payload = sigma_action_len(sa);
51 		break;
52 	default:
53 		break;
54 	}
55 
56 	payload = ALIGN(payload, 2);
57 
58 	return payload + sizeof(struct sigma_action);
59 }
60 
61 /*
62  * Returns a negative error value in case of an error, 0 if processing of
63  * the firmware should be stopped after this action, 1 otherwise.
64  */
65 static int
66 process_sigma_action(struct sigma_firmware *ssfw, struct sigma_action *sa)
67 {
68 	size_t len = sigma_action_len(sa);
69 	int ret;
70 
71 	pr_debug("%s: instr:%i addr:%#x len:%zu\n", __func__,
72 		sa->instr, sa->addr, len);
73 
74 	switch (sa->instr) {
75 	case SIGMA_ACTION_WRITEXBYTES:
76 	case SIGMA_ACTION_WRITESINGLE:
77 	case SIGMA_ACTION_WRITESAFELOAD:
78 		ret = ssfw->write(ssfw->control_data, sa, len);
79 		if (ret < 0)
80 			return -EINVAL;
81 		break;
82 	case SIGMA_ACTION_DELAY:
83 		udelay(len);
84 		len = 0;
85 		break;
86 	case SIGMA_ACTION_END:
87 		return 0;
88 	default:
89 		return -EINVAL;
90 	}
91 
92 	return 1;
93 }
94 
95 static int
96 process_sigma_actions(struct sigma_firmware *ssfw)
97 {
98 	struct sigma_action *sa;
99 	size_t size;
100 	int ret;
101 
102 	while (ssfw->pos + sizeof(*sa) <= ssfw->fw->size) {
103 		sa = (struct sigma_action *)(ssfw->fw->data + ssfw->pos);
104 
105 		size = sigma_action_size(sa);
106 		ssfw->pos += size;
107 		if (ssfw->pos > ssfw->fw->size || size == 0)
108 			break;
109 
110 		ret = process_sigma_action(ssfw, sa);
111 
112 		pr_debug("%s: action returned %i\n", __func__, ret);
113 
114 		if (ret <= 0)
115 			return ret;
116 	}
117 
118 	if (ssfw->pos != ssfw->fw->size)
119 		return -EINVAL;
120 
121 	return 0;
122 }
123 
124 int _process_sigma_firmware(struct device *dev,
125 	struct sigma_firmware *ssfw, const char *name)
126 {
127 	int ret;
128 	struct sigma_firmware_header *ssfw_head;
129 	const struct firmware *fw;
130 	u32 crc;
131 
132 	pr_debug("%s: loading firmware %s\n", __func__, name);
133 
134 	/* first load the blob */
135 	ret = request_firmware(&fw, name, dev);
136 	if (ret) {
137 		pr_debug("%s: request_firmware() failed with %i\n", __func__, ret);
138 		return ret;
139 	}
140 	ssfw->fw = fw;
141 
142 	/* then verify the header */
143 	ret = -EINVAL;
144 
145 	/*
146 	 * Reject too small or unreasonable large files. The upper limit has been
147 	 * chosen a bit arbitrarily, but it should be enough for all practical
148 	 * purposes and having the limit makes it easier to avoid integer
149 	 * overflows later in the loading process.
150 	 */
151 	if (fw->size < sizeof(*ssfw_head) || fw->size >= 0x4000000) {
152 		dev_err(dev, "Failed to load firmware: Invalid size\n");
153 		goto done;
154 	}
155 
156 	ssfw_head = (void *)fw->data;
157 	if (memcmp(ssfw_head->magic, SIGMA_MAGIC, ARRAY_SIZE(ssfw_head->magic))) {
158 		dev_err(dev, "Failed to load firmware: Invalid magic\n");
159 		goto done;
160 	}
161 
162 	crc = crc32(0, fw->data + sizeof(*ssfw_head),
163 			fw->size - sizeof(*ssfw_head));
164 	pr_debug("%s: crc=%x\n", __func__, crc);
165 	if (crc != le32_to_cpu(ssfw_head->crc)) {
166 		dev_err(dev, "Failed to load firmware: Wrong crc checksum: expected %x got %x\n",
167 			le32_to_cpu(ssfw_head->crc), crc);
168 		goto done;
169 	}
170 
171 	ssfw->pos = sizeof(*ssfw_head);
172 
173 	/* finally process all of the actions */
174 	ret = process_sigma_actions(ssfw);
175 
176  done:
177 	release_firmware(fw);
178 
179 	pr_debug("%s: loaded %s\n", __func__, name);
180 
181 	return ret;
182 }
183 EXPORT_SYMBOL_GPL(_process_sigma_firmware);
184 
185 MODULE_LICENSE("GPL");
186