libertas: add sysfs hooks to update boot2 and persistent firmware

To use these features, copy the boot2 and firmware images to /lib/firmware and:

echo <boot2_image_name> > /sys/class/net/ethX/lbs_flash_boot2
echo <firmware_image_name> > /sys/class/net/ethX/lbs_flash_fw
Signed-off-by: Brian Cavagnolo <brian@cozybit.com>
Acked-by: Dan Williams <dcbw@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/libertas/if_usb.c

@@ -51,6 +51,62 @@ static void if_usb_free(struct if_usb_card *cardp);
 static int if_usb_submit_rx_urb(struct if_usb_card *cardp);
 static int if_usb_reset_device(struct if_usb_card *cardp);
 
+/* sysfs hooks */
+
+/**
+ *  Set function to write firmware to device's persistent memory
+ */
+static ssize_t if_usb_firmware_set(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct lbs_private *priv = to_net_dev(dev)->priv;
+	struct if_usb_card *cardp = priv->card;
+	char fwname[FIRMWARE_NAME_MAX];
+	int ret;
+
+	sscanf(buf, "%29s", fwname); /* FIRMWARE_NAME_MAX - 1 = 29 */
+	ret = if_usb_prog_firmware(cardp, fwname, BOOT_CMD_UPDATE_FW);
+	if (ret == 0)
+		return count;
+
+	return ret;
+}
+
+/**
+ * lbs_flash_fw attribute to be exported per ethX interface through sysfs
+ * (/sys/class/net/ethX/lbs_flash_fw).  Use this like so to write firmware to
+ * the device's persistent memory:
+ * echo usb8388-5.126.0.p5.bin > /sys/class/net/ethX/lbs_flash_fw
+ */
+static DEVICE_ATTR(lbs_flash_fw, 0200, NULL, if_usb_firmware_set);
+
+/**
+ *  Set function to write firmware to device's persistent memory
+ */
+static ssize_t if_usb_boot2_set(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct lbs_private *priv = to_net_dev(dev)->priv;
+	struct if_usb_card *cardp = priv->card;
+	char fwname[FIRMWARE_NAME_MAX];
+	int ret;
+
+	sscanf(buf, "%29s", fwname); /* FIRMWARE_NAME_MAX - 1 = 29 */
+	ret = if_usb_prog_firmware(cardp, fwname, BOOT_CMD_UPDATE_BOOT2);
+	if (ret == 0)
+		return count;
+
+	return ret;
+}
+
+/**
+ * lbs_flash_boot2 attribute to be exported per ethX interface through sysfs
+ * (/sys/class/net/ethX/lbs_flash_boot2).  Use this like so to write firmware
+ * to the device's persistent memory:
+ * echo usb8388-5.126.0.p5.bin > /sys/class/net/ethX/lbs_flash_boot2
+ */
+static DEVICE_ATTR(lbs_flash_boot2, 0200, NULL, if_usb_boot2_set);
+
 /**
  *  @brief  call back function to handle the status of the URB
  *  @param urb 		pointer to urb structure
@@ -263,6 +319,12 @@ static int if_usb_probe(struct usb_interface *intf,
 	usb_get_dev(udev);
 	usb_set_intfdata(intf, cardp);
 
+	if (device_create_file(&priv->dev->dev, &dev_attr_lbs_flash_fw))
+		lbs_pr_err("cannot register lbs_flash_fw attribute\n");
+
+	if (device_create_file(&priv->dev->dev, &dev_attr_lbs_flash_boot2))
+		lbs_pr_err("cannot register lbs_flash_boot2 attribute\n");
+
 	return 0;
 
 err_start_card:
@@ -288,6 +350,9 @@ static void if_usb_disconnect(struct usb_interface *intf)
 
 	lbs_deb_enter(LBS_DEB_MAIN);
 
+	device_remove_file(&priv->dev->dev, &dev_attr_lbs_flash_boot2);
+	device_remove_file(&priv->dev->dev, &dev_attr_lbs_flash_fw);
+
 	cardp->surprise_removed = 1;
 
 	if (priv) {