USB: cdc-acm: export parsed capabilities through sysfs

this patch exports the attributes cdc-acm knows about a device through sysfs.

Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

2 files changed, 79 insertions, 5 deletions

diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index 31ae661e586a..14de3b1b6a20 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -212,7 +212,41 @@ static int acm_write_start(struct acm *acm)
         }
         return rc;
 }
+/*
+ * attributes exported through sysfs
+ */
+static ssize_t show_caps
+(struct device *dev, struct device_attribute *attr, char *buf)
+{
+        struct usb_interface *intf = to_usb_interface(dev);
+        struct acm *acm = usb_get_intfdata(intf);
+
+        return sprintf(buf, "%d", acm->ctrl_caps);
+}
+static DEVICE_ATTR(bmCapabilities, S_IRUGO, show_caps, NULL);
+
+static ssize_t show_country_codes
+(struct device *dev, struct device_attribute *attr, char *buf)
+{
+        struct usb_interface *intf = to_usb_interface(dev);
+        struct acm *acm = usb_get_intfdata(intf);
+
+        memcpy(buf, acm->country_codes, acm->country_code_size);
+        return acm->country_code_size;
+}
+
+static DEVICE_ATTR(wCountryCodes, S_IRUGO, show_country_codes, NULL);
+
+static ssize_t show_country_rel_date
+(struct device *dev, struct device_attribute *attr, char *buf)
+{
+        struct usb_interface *intf = to_usb_interface(dev);
+        struct acm *acm = usb_get_intfdata(intf);
+
+        return sprintf(buf, "%d", acm->country_rel_date);
+}
 
+static DEVICE_ATTR(iCountryCodeRelDate, S_IRUGO, show_country_rel_date, NULL);
 /*
  * Interrupt handlers for various ACM device responses
  */
@@ -514,6 +548,7 @@ static void acm_tty_unregister(struct acm *acm)
         usb_free_urb(acm->writeurb);
         for (i = 0; i < nr; i++)
                 usb_free_urb(acm->ru[i].urb);
+        kfree(acm->country_codes);
         kfree(acm);
 }
 
@@ -761,6 +796,7 @@ static int acm_probe (struct usb_interface *intf,
                       const struct usb_device_id *id)
 {
         struct usb_cdc_union_desc *union_header = NULL;
+        struct usb_cdc_country_functional_desc *cfd = NULL;
         char *buffer = intf->altsetting->extra;
         int buflen = intf->altsetting->extralen;
         struct usb_interface *control_interface;
@@ -824,8 +860,9 @@ static int acm_probe (struct usb_interface *intf,
                                 union_header = (struct usb_cdc_union_desc *)
                                                         buffer;
                                 break;
-                        case USB_CDC_COUNTRY_TYPE: /* maybe somehow export */
-                                break; /* for now we ignore it */
+                        case USB_CDC_COUNTRY_TYPE: /* export through sysfs*/
+                                cfd = (struct usb_cdc_country_functional_desc *)buffer;
+                                break;
                         case USB_CDC_HEADER_TYPE: /* maybe check version */ 
                                 break; /* for now we ignore it */ 
                         case USB_CDC_ACM_TYPE:
@@ -983,6 +1020,34 @@ skip_normal_probe:
                 goto alloc_fail7;
         }
 
+        usb_set_intfdata (intf, acm);
+
+        i = device_create_file(&intf->dev, &dev_attr_bmCapabilities);
+        if (i < 0)
+                goto alloc_fail8;
+
+        if (cfd) { /* export the country data */
+                acm->country_codes = kmalloc(cfd->bLength - 4, GFP_KERNEL);
+                if (!acm->country_codes)
+                        goto skip_countries;
+                acm->country_code_size = cfd->bLength - 4;
+                memcpy(acm->country_codes, (u8 *)&cfd->wCountyCode0, cfd->bLength - 4);
+                acm->country_rel_date = cfd->iCountryCodeRelDate;
+
+                i = device_create_file(&intf->dev, &dev_attr_wCountryCodes);
+                if (i < 0) {
+                        kfree(acm->country_codes);
+                        goto skip_countries;
+                }
+
+                i = device_create_file(&intf->dev, &dev_attr_iCountryCodeRelDate);
+                if (i < 0) {
+                        kfree(acm->country_codes);
+                        goto skip_countries;
+                }
+        }
+
+skip_countries:
         usb_fill_int_urb(acm->ctrlurb, usb_dev, usb_rcvintpipe(usb_dev, epctrl->bEndpointAddress),
                          acm->ctrl_buffer, ctrlsize, acm_ctrl_irq, acm, epctrl->bInterval);
         acm->ctrlurb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
@@ -1006,9 +1071,10 @@ skip_normal_probe:
         tty_register_device(acm_tty_driver, minor, &control_interface->dev);
 
         acm_table[minor] = acm;
-        usb_set_intfdata (intf, acm);
-        return 0;
 
+        return 0;
+alloc_fail8:
+        usb_free_urb(acm->writeurb);
 alloc_fail7:
         for (i = 0; i < num_rx_buf; i++)
                 usb_buffer_free(usb_dev, acm->readsize, acm->rb[i].base, acm->rb[i].dma);
@@ -1027,7 +1093,7 @@ alloc_fail:
 
 static void acm_disconnect(struct usb_interface *intf)
 {
-        struct acm *acm = usb_get_intfdata (intf);
+        struct acm *acm = usb_get_intfdata(intf);
         struct usb_device *usb_dev = interface_to_usbdev(intf);
         int i;
 
@@ -1041,6 +1107,11 @@ static void acm_disconnect(struct usb_interface *intf)
                 mutex_unlock(&open_mutex);
                 return;
         }
+        if (acm->country_codes){
+                device_remove_file(&intf->dev, &dev_attr_wCountryCodes);
+                device_remove_file(&intf->dev, &dev_attr_iCountryCodeRelDate);
+        }
+        device_remove_file(&intf->dev, &dev_attr_bmCapabilities);
         acm->dev = NULL;
         usb_set_intfdata(acm->control, NULL);
         usb_set_intfdata(acm->data, NULL);
diff --git a/drivers/usb/class/cdc-acm.h b/drivers/usb/class/cdc-acm.h
index 1bcaea32cfc1..09f7765dbf8d 100644
--- a/drivers/usb/class/cdc-acm.h
+++ b/drivers/usb/class/cdc-acm.h
@@ -91,6 +91,9 @@ struct acm {
         struct urb *ctrlurb, *writeurb;                 /* urbs */
         u8 *ctrl_buffer;                                /* buffers of urbs */
         dma_addr_t ctrl_dma;                            /* dma handles of buffers */
+        u8 *country_codes;                              /* country codes from device */
+        unsigned int country_code_size;                 /* size of this buffer */
+        unsigned int country_rel_date;                  /* release date of version */
         struct acm_wb wb[ACM_NW];
         struct acm_ru ru[ACM_NR];
         struct acm_rb rb[ACM_NR];