drivers/media/usb/dvb-usb/dvb-usb-firmware.c

Source file repositories/reference/linux-study-clean/drivers/media/usb/dvb-usb/dvb-usb-firmware.c

File Facts

System
Linux kernel
Corpus path
drivers/media/usb/dvb-usb/dvb-usb-firmware.c
Extension
.c
Size
4158 bytes
Lines
156
Domain
Driver Families
Bucket
drivers/media
Inferred role
Driver Families: exported/initcall integration point
Status
integration implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

struct usb_cypress_controller {
	int id;
	const char *name;       /* name of the usb controller */
	u16 cpu_cs_register;    /* needs to be restarted, when the firmware has been downloaded. */
};

static struct usb_cypress_controller cypress[] = {
	{ .id = DEVICE_SPECIFIC, .name = "Device specific", .cpu_cs_register = 0 },
	{ .id = CYPRESS_AN2135,  .name = "Cypress AN2135",  .cpu_cs_register = 0x7f92 },
	{ .id = CYPRESS_AN2235,  .name = "Cypress AN2235",  .cpu_cs_register = 0x7f92 },
	{ .id = CYPRESS_FX2,     .name = "Cypress FX2",     .cpu_cs_register = 0xe600 },
};

/*
 * load a firmware packet to the device
 */
static int usb_cypress_writemem(struct usb_device *udev,u16 addr,u8 *data, u8 len)
{
	return usb_control_msg(udev, usb_sndctrlpipe(udev,0),
			0xa0, USB_TYPE_VENDOR, addr, 0x00, data, len, 5000);
}

int usb_cypress_load_firmware(struct usb_device *udev, const struct firmware *fw, int type)
{
	struct hexline *hx;
	u8 *buf;
	int ret, pos = 0;
	u16 cpu_cs_register = cypress[type].cpu_cs_register;

	buf = kmalloc(sizeof(*hx), GFP_KERNEL);
	if (!buf)
		return -ENOMEM;
	hx = (struct hexline *)buf;

	/* stop the CPU */
	buf[0] = 1;
	if (usb_cypress_writemem(udev, cpu_cs_register, buf, 1) != 1)
		err("could not stop the USB controller CPU.");

	while ((ret = dvb_usb_get_hexline(fw, hx, &pos)) > 0) {
		deb_fw("writing to address 0x%04x (buffer: 0x%02x %02x)\n", hx->addr, hx->len, hx->chk);
		ret = usb_cypress_writemem(udev, hx->addr, hx->data, hx->len);

		if (ret != hx->len) {
			err("error while transferring firmware (transferred size: %d, block size: %d)",
				ret, hx->len);
			ret = -EINVAL;
			break;
		}
	}
	if (ret < 0) {
		err("firmware download failed at %d with %d",pos,ret);
		kfree(buf);
		return ret;
	}

	if (ret == 0) {
		/* restart the CPU */
		buf[0] = 0;
		if (usb_cypress_writemem(udev, cpu_cs_register, buf, 1) != 1) {
			err("could not restart the USB controller CPU.");
			ret = -EINVAL;
		}
	} else
		ret = -EIO;

	kfree(buf);

	return ret;
}
EXPORT_SYMBOL(usb_cypress_load_firmware);

int dvb_usb_download_firmware(struct usb_device *udev,
			      const struct dvb_usb_device_properties *props)
{
	int ret;
	const struct firmware *fw = NULL;

	if ((ret = request_firmware(&fw, props->firmware, &udev->dev)) != 0) {
		err("did not find the firmware file '%s' (status %d). You can use <kernel_dir>/scripts/get_dvb_firmware to get the firmware",
			props->firmware,ret);
		return ret;
	}

	info("downloading firmware from file '%s'",props->firmware);

	switch (props->usb_ctrl) {
		case CYPRESS_AN2135:
		case CYPRESS_AN2235:
		case CYPRESS_FX2:

Annotation

Implementation Notes