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/module.h>
 15#include <linux/sigma.h>
 16
 17/* Return: 0==OK, <0==error, =1 ==no more actions */
 18static int
 19process_sigma_action(struct i2c_client *client, struct sigma_firmware *ssfw)
 20{
 21	struct sigma_action *sa = (void *)(ssfw->fw->data + ssfw->pos);
 22	size_t len = sigma_action_len(sa);
 23	int ret = 0;
 24
 25	pr_debug("%s: instr:%i addr:%#x len:%zu\n", __func__,
 26		sa->instr, sa->addr, len);
 27
 28	switch (sa->instr) {
 29	case SIGMA_ACTION_WRITEXBYTES:
 30	case SIGMA_ACTION_WRITESINGLE:
 31	case SIGMA_ACTION_WRITESAFELOAD:
 32		if (ssfw->fw->size < ssfw->pos + len)
 33			return -EINVAL;
 34		ret = i2c_master_send(client, (void *)&sa->addr, len);
 35		if (ret < 0)
 36			return -EINVAL;
 37		break;
 38
 39	case SIGMA_ACTION_DELAY:
 40		ret = 0;
 41		udelay(len);
 42		len = 0;
 43		break;
 44
 45	case SIGMA_ACTION_END:
 46		return 1;
 47
 48	default:
 49		return -EINVAL;
 50	}
 51
 52	/* when arrive here ret=0 or sent data */
 53	ssfw->pos += sigma_action_size(sa, len);
 54	return ssfw->pos == ssfw->fw->size;
 55}
 56
 57static int
 58process_sigma_actions(struct i2c_client *client, struct sigma_firmware *ssfw)
 59{
 60	pr_debug("%s: processing %p\n", __func__, ssfw);
 61
 62	while (1) {
 63		int ret = process_sigma_action(client, ssfw);
 64		pr_debug("%s: action returned %i\n", __func__, ret);
 65		if (ret == 1)
 66			return 0;
 67		else if (ret)
 68			return ret;
 69	}
 70}
 71
 72int process_sigma_firmware(struct i2c_client *client, const char *name)
 73{
 74	int ret;
 75	struct sigma_firmware_header *ssfw_head;
 76	struct sigma_firmware ssfw;
 77	const struct firmware *fw;
 78	u32 crc;
 79
 80	pr_debug("%s: loading firmware %s\n", __func__, name);
 81
 82	/* first load the blob */
 83	ret = request_firmware(&fw, name, &client->dev);
 84	if (ret) {
 85		pr_debug("%s: request_firmware() failed with %i\n", __func__, ret);
 86		return ret;
 87	}
 88	ssfw.fw = fw;
 89
 90	/* then verify the header */
 91	ret = -EINVAL;
 92	if (fw->size < sizeof(*ssfw_head))
 93		goto done;
 94
 95	ssfw_head = (void *)fw->data;
 96	if (memcmp(ssfw_head->magic, SIGMA_MAGIC, ARRAY_SIZE(ssfw_head->magic)))
 97		goto done;
 98
 99	crc = crc32(0, fw->data, fw->size);
100	pr_debug("%s: crc=%x\n", __func__, crc);
101	if (crc != ssfw_head->crc)
102		goto done;
103
104	ssfw.pos = sizeof(*ssfw_head);
105
106	/* finally process all of the actions */
107	ret = process_sigma_actions(client, &ssfw);
108
109 done:
110	release_firmware(fw);
111
112	pr_debug("%s: loaded %s\n", __func__, name);
113
114	return ret;
115}
116EXPORT_SYMBOL(process_sigma_firmware);
117
118MODULE_LICENSE("GPL");