sound/soc/codecs/sigmadsp.c

   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");