ASoC: Move SigmaDSP firmware loader to ASoC

It has been pointed out previously, that the firmware subsystem is not the right
place for the SigmaDSP firmware loader. Furthermore the SigmaDSP is currently
only used in audio products and we are aiming for better integration into the
ASoC framework in the future, with support for ALSA controls for firmware
parameters and support dynamic power management as well. So the natural choice
for the SigmaDSP firmware loader is the ASoC subsystem.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 154 insertions, 0 deletions

diff --git a/sound/soc/codecs/sigmadsp.c b/sound/soc/codecs/sigmadsp.c
new file mode 100644
index 000000000000..acb97a9834aa
--- /dev/null
+++ b/sound/soc/codecs/sigmadsp.c
@@ -0,0 +1,154 @@
+/*
+ * Load Analog Devices SigmaStudio firmware files
+ *
+ * Copyright 2009-2011 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+#include <linux/crc32.h>
+#include <linux/delay.h>
+#include <linux/firmware.h>
+#include <linux/kernel.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+
+#include "sigmadsp.h"
+
+static size_t sigma_action_size(struct sigma_action *sa)
+{
+        size_t payload = 0;
+
+        switch (sa->instr) {
+        case SIGMA_ACTION_WRITEXBYTES:
+        case SIGMA_ACTION_WRITESINGLE:
+        case SIGMA_ACTION_WRITESAFELOAD:
+                payload = sigma_action_len(sa);
+                break;
+        default:
+                break;
+        }
+
+        payload = ALIGN(payload, 2);
+
+        return payload + sizeof(struct sigma_action);
+}
+
+/*
+ * Returns a negative error value in case of an error, 0 if processing of
+ * the firmware should be stopped after this action, 1 otherwise.
+ */
+static int
+process_sigma_action(struct i2c_client *client, struct sigma_action *sa)
+{
+        size_t len = sigma_action_len(sa);
+        int ret;
+
+        pr_debug("%s: instr:%i addr:%#x len:%zu\n", __func__,
+                sa->instr, sa->addr, len);
+
+        switch (sa->instr) {
+        case SIGMA_ACTION_WRITEXBYTES:
+        case SIGMA_ACTION_WRITESINGLE:
+        case SIGMA_ACTION_WRITESAFELOAD:
+                ret = i2c_master_send(client, (void *)&sa->addr, len);
+                if (ret < 0)
+                        return -EINVAL;
+                break;
+        case SIGMA_ACTION_DELAY:
+                udelay(len);
+                len = 0;
+                break;
+        case SIGMA_ACTION_END:
+                return 0;
+        default:
+                return -EINVAL;
+        }
+
+        return 1;
+}
+
+static int
+process_sigma_actions(struct i2c_client *client, struct sigma_firmware *ssfw)
+{
+        struct sigma_action *sa;
+        size_t size;
+        int ret;
+
+        while (ssfw->pos + sizeof(*sa) <= ssfw->fw->size) {
+                sa = (struct sigma_action *)(ssfw->fw->data + ssfw->pos);
+
+                size = sigma_action_size(sa);
+                ssfw->pos += size;
+                if (ssfw->pos > ssfw->fw->size || size == 0)
+                        break;
+
+                ret = process_sigma_action(client, sa);
+
+                pr_debug("%s: action returned %i\n", __func__, ret);
+
+                if (ret <= 0)
+                        return ret;
+        }
+
+        if (ssfw->pos != ssfw->fw->size)
+                return -EINVAL;
+
+        return 0;
+}
+
+int process_sigma_firmware(struct i2c_client *client, const char *name)
+{
+        int ret;
+        struct sigma_firmware_header *ssfw_head;
+        struct sigma_firmware ssfw;
+        const struct firmware *fw;
+        u32 crc;
+
+        pr_debug("%s: loading firmware %s\n", __func__, name);
+
+        /* first load the blob */
+        ret = request_firmware(&fw, name, &client->dev);
+        if (ret) {
+                pr_debug("%s: request_firmware() failed with %i\n", __func__, ret);
+                return ret;
+        }
+        ssfw.fw = fw;
+
+        /* then verify the header */
+        ret = -EINVAL;
+
+        /*
+         * Reject too small or unreasonable large files. The upper limit has been
+         * chosen a bit arbitrarily, but it should be enough for all practical
+         * purposes and having the limit makes it easier to avoid integer
+         * overflows later in the loading process.
+         */
+        if (fw->size < sizeof(*ssfw_head) || fw->size >= 0x4000000)
+                goto done;
+
+        ssfw_head = (void *)fw->data;
+        if (memcmp(ssfw_head->magic, SIGMA_MAGIC, ARRAY_SIZE(ssfw_head->magic)))
+                goto done;
+
+        crc = crc32(0, fw->data + sizeof(*ssfw_head),
+                        fw->size - sizeof(*ssfw_head));
+        pr_debug("%s: crc=%x\n", __func__, crc);
+        if (crc != le32_to_cpu(ssfw_head->crc))
+                goto done;
+
+        ssfw.pos = sizeof(*ssfw_head);
+
+        /* finally process all of the actions */
+        ret = process_sigma_actions(client, &ssfw);
+
+ done:
+        release_firmware(fw);
+
+        pr_debug("%s: loaded %s\n", __func__, name);
+
+        return ret;
+}
+EXPORT_SYMBOL(process_sigma_firmware);
+
+MODULE_LICENSE("GPL");