net: cdc_ncm: factor out one-time device initialization
[pandora-kernel.git] / drivers / net / usb / cdc_ncm.c
index e5f5153..b70e061 100644 (file)
@@ -120,19 +120,51 @@ static void cdc_ncm_update_rxtx_max(struct usbnet *dev, u32 new_rx, u32 new_tx)
        ctx->tx_max = val;
 }
 
-static int cdc_ncm_setup(struct usbnet *dev)
+/* helpers for NCM and MBIM differences */
+static u8 cdc_ncm_flags(struct usbnet *dev)
 {
        struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
-       u32 val;
-       u8 flags;
-       u8 iface_no;
-       int err;
-       int eth_hlen;
-       u16 mbim_mtu;
-       u16 ntb_fmt_supported;
-       __le16 max_datagram_size;
 
-       iface_no = ctx->control->cur_altsetting->desc.bInterfaceNumber;
+       if (cdc_ncm_comm_intf_is_mbim(dev->intf->cur_altsetting) && ctx->mbim_desc)
+               return ctx->mbim_desc->bmNetworkCapabilities;
+       if (ctx->func_desc)
+               return ctx->func_desc->bmNetworkCapabilities;
+       return 0;
+}
+
+static int cdc_ncm_eth_hlen(struct usbnet *dev)
+{
+       if (cdc_ncm_comm_intf_is_mbim(dev->intf->cur_altsetting))
+               return 0;
+       return ETH_HLEN;
+}
+
+static u32 cdc_ncm_min_dgram_size(struct usbnet *dev)
+{
+       if (cdc_ncm_comm_intf_is_mbim(dev->intf->cur_altsetting))
+               return CDC_MBIM_MIN_DATAGRAM_SIZE;
+       return CDC_NCM_MIN_DATAGRAM_SIZE;
+}
+
+static u32 cdc_ncm_max_dgram_size(struct usbnet *dev)
+{
+       struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
+
+       if (cdc_ncm_comm_intf_is_mbim(dev->intf->cur_altsetting) && ctx->mbim_desc)
+               return le16_to_cpu(ctx->mbim_desc->wMaxSegmentSize);
+       if (ctx->ether_desc)
+               return le16_to_cpu(ctx->ether_desc->wMaxSegmentSize);
+       return CDC_NCM_MAX_DATAGRAM_SIZE;
+}
+
+/* initial one-time device setup.  MUST be called with the data interface
+ * in altsetting 0
+ */
+static int cdc_ncm_init(struct usbnet *dev)
+{
+       struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
+       u8 iface_no = ctx->control->cur_altsetting->desc.bInterfaceNumber;
+       int err;
 
        err = usbnet_read_cmd(dev, USB_CDC_GET_NTB_PARAMETERS,
                              USB_TYPE_CLASS | USB_DIR_IN
@@ -144,7 +176,35 @@ static int cdc_ncm_setup(struct usbnet *dev)
                return err; /* GET_NTB_PARAMETERS is required */
        }
 
-       /* read correct set of parameters according to device mode */
+       /* set CRC Mode */
+       if (cdc_ncm_flags(dev) & USB_CDC_NCM_NCAP_CRC_MODE) {
+               dev_dbg(&dev->intf->dev, "Setting CRC mode off\n");
+               err = usbnet_write_cmd(dev, USB_CDC_SET_CRC_MODE,
+                                      USB_TYPE_CLASS | USB_DIR_OUT
+                                      | USB_RECIP_INTERFACE,
+                                      USB_CDC_NCM_CRC_NOT_APPENDED,
+                                      iface_no, NULL, 0);
+               if (err < 0)
+                       dev_err(&dev->intf->dev, "SET_CRC_MODE failed\n");
+       }
+
+       /* set NTB format, if both formats are supported.
+        *
+        * "The host shall only send this command while the NCM Data
+        *  Interface is in alternate setting 0."
+        */
+       if (le16_to_cpu(ctx->ncm_parm.bmNtbFormatsSupported) & USB_CDC_NCM_NTH32_SIGN) {
+               dev_dbg(&dev->intf->dev, "Setting NTB format to 16-bit\n");
+               err = usbnet_write_cmd(dev, USB_CDC_SET_NTB_FORMAT,
+                                      USB_TYPE_CLASS | USB_DIR_OUT
+                                      | USB_RECIP_INTERFACE,
+                                      USB_CDC_NCM_NTB16_FORMAT,
+                                      iface_no, NULL, 0);
+               if (err < 0)
+                       dev_err(&dev->intf->dev, "SET_NTB_FORMAT failed\n");
+       }
+
+       /* set initial device values */
        ctx->rx_max = le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize);
        ctx->tx_max = le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize);
        ctx->tx_remainder = le16_to_cpu(ctx->ncm_parm.wNdpOutPayloadRemainder);
@@ -152,43 +212,73 @@ static int cdc_ncm_setup(struct usbnet *dev)
        ctx->tx_ndp_modulus = le16_to_cpu(ctx->ncm_parm.wNdpOutAlignment);
        /* devices prior to NCM Errata shall set this field to zero */
        ctx->tx_max_datagrams = le16_to_cpu(ctx->ncm_parm.wNtbOutMaxDatagrams);
-       ntb_fmt_supported = le16_to_cpu(ctx->ncm_parm.bmNtbFormatsSupported);
-
-       /* there are some minor differences in NCM and MBIM defaults */
-       if (cdc_ncm_comm_intf_is_mbim(ctx->control->cur_altsetting)) {
-               if (!ctx->mbim_desc)
-                       return -EINVAL;
-               eth_hlen = 0;
-               flags = ctx->mbim_desc->bmNetworkCapabilities;
-               ctx->max_datagram_size = le16_to_cpu(ctx->mbim_desc->wMaxSegmentSize);
-               if (ctx->max_datagram_size < CDC_MBIM_MIN_DATAGRAM_SIZE)
-                       ctx->max_datagram_size = CDC_MBIM_MIN_DATAGRAM_SIZE;
-       } else {
-               if (!ctx->func_desc)
-                       return -EINVAL;
-               eth_hlen = ETH_HLEN;
-               flags = ctx->func_desc->bmNetworkCapabilities;
-               ctx->max_datagram_size = le16_to_cpu(ctx->ether_desc->wMaxSegmentSize);
-               if (ctx->max_datagram_size < CDC_NCM_MIN_DATAGRAM_SIZE)
-                       ctx->max_datagram_size = CDC_NCM_MIN_DATAGRAM_SIZE;
-       }
-
-       /* common absolute max for NCM and MBIM */
-       if (ctx->max_datagram_size > CDC_NCM_MAX_DATAGRAM_SIZE)
-               ctx->max_datagram_size = CDC_NCM_MAX_DATAGRAM_SIZE;
 
        dev_dbg(&dev->intf->dev,
                "dwNtbInMaxSize=%u dwNtbOutMaxSize=%u wNdpOutPayloadRemainder=%u wNdpOutDivisor=%u wNdpOutAlignment=%u wNtbOutMaxDatagrams=%u flags=0x%x\n",
                ctx->rx_max, ctx->tx_max, ctx->tx_remainder, ctx->tx_modulus,
-               ctx->tx_ndp_modulus, ctx->tx_max_datagrams, flags);
+               ctx->tx_ndp_modulus, ctx->tx_max_datagrams, cdc_ncm_flags(dev));
 
        /* max count of tx datagrams */
        if ((ctx->tx_max_datagrams == 0) ||
                        (ctx->tx_max_datagrams > CDC_NCM_DPT_DATAGRAMS_MAX))
                ctx->tx_max_datagrams = CDC_NCM_DPT_DATAGRAMS_MAX;
 
-       /* clamp rx_max and tx_max and inform device */
-       cdc_ncm_update_rxtx_max(dev, le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize), le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize));
+       return 0;
+}
+
+/* set a new max datagram size */
+static void cdc_ncm_set_dgram_size(struct usbnet *dev, int new_size)
+{
+       struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
+       u8 iface_no = ctx->control->cur_altsetting->desc.bInterfaceNumber;
+       __le16 max_datagram_size;
+       u16 mbim_mtu;
+       int err;
+
+       /* set default based on descriptors */
+       ctx->max_datagram_size = clamp_t(u32, new_size,
+                                        cdc_ncm_min_dgram_size(dev),
+                                        CDC_NCM_MAX_DATAGRAM_SIZE);
+
+       /* inform the device about the selected Max Datagram Size? */
+       if (!(cdc_ncm_flags(dev) & USB_CDC_NCM_NCAP_MAX_DATAGRAM_SIZE))
+               goto out;
+
+       /* read current mtu value from device */
+       err = usbnet_read_cmd(dev, USB_CDC_GET_MAX_DATAGRAM_SIZE,
+                             USB_TYPE_CLASS | USB_DIR_IN | USB_RECIP_INTERFACE,
+                             0, iface_no, &max_datagram_size, 2);
+       if (err < 0) {
+               dev_dbg(&dev->intf->dev, "GET_MAX_DATAGRAM_SIZE failed\n");
+               goto out;
+       }
+
+       if (le16_to_cpu(max_datagram_size) == ctx->max_datagram_size)
+               goto out;
+
+       max_datagram_size = cpu_to_le16(ctx->max_datagram_size);
+       err = usbnet_write_cmd(dev, USB_CDC_SET_MAX_DATAGRAM_SIZE,
+                              USB_TYPE_CLASS | USB_DIR_OUT | USB_RECIP_INTERFACE,
+                              0, iface_no, &max_datagram_size, 2);
+       if (err < 0)
+               dev_dbg(&dev->intf->dev, "SET_MAX_DATAGRAM_SIZE failed\n");
+
+out:
+       /* set MTU to max supported by the device if necessary */
+       dev->net->mtu = min_t(int, dev->net->mtu, ctx->max_datagram_size - cdc_ncm_eth_hlen(dev));
+
+       /* do not exceed operater preferred MTU */
+       if (ctx->mbim_extended_desc) {
+               mbim_mtu = le16_to_cpu(ctx->mbim_extended_desc->wMTU);
+               if (mbim_mtu != 0 && mbim_mtu < dev->net->mtu)
+                       dev->net->mtu = mbim_mtu;
+       }
+}
+
+static void cdc_ncm_fix_modulus(struct usbnet *dev)
+{
+       struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
+       u32 val;
 
        /*
         * verify that the structure alignment is:
@@ -225,68 +315,26 @@ static int cdc_ncm_setup(struct usbnet *dev)
        }
 
        /* adjust TX-remainder according to NCM specification. */
-       ctx->tx_remainder = ((ctx->tx_remainder - eth_hlen) &
+       ctx->tx_remainder = ((ctx->tx_remainder - cdc_ncm_eth_hlen(dev)) &
                             (ctx->tx_modulus - 1));
+}
 
-       /* additional configuration */
-
-       /* set CRC Mode */
-       if (flags & USB_CDC_NCM_NCAP_CRC_MODE) {
-               err = usbnet_write_cmd(dev, USB_CDC_SET_CRC_MODE,
-                                      USB_TYPE_CLASS | USB_DIR_OUT
-                                      | USB_RECIP_INTERFACE,
-                                      USB_CDC_NCM_CRC_NOT_APPENDED,
-                                      iface_no, NULL, 0);
-               if (err < 0)
-                       dev_dbg(&dev->intf->dev, "Setting CRC mode off failed\n");
-       }
-
-       /* set NTB format, if both formats are supported */
-       if (ntb_fmt_supported & USB_CDC_NCM_NTH32_SIGN) {
-               err = usbnet_write_cmd(dev, USB_CDC_SET_NTB_FORMAT,
-                                      USB_TYPE_CLASS | USB_DIR_OUT
-                                      | USB_RECIP_INTERFACE,
-                                      USB_CDC_NCM_NTB16_FORMAT,
-                                      iface_no, NULL, 0);
-               if (err < 0)
-                       dev_dbg(&dev->intf->dev, "Setting NTB format to 16-bit failed\n");
-       }
-
-       /* inform the device about the selected Max Datagram Size */
-       if (!(flags & USB_CDC_NCM_NCAP_MAX_DATAGRAM_SIZE))
-               goto out;
-
-       /* read current mtu value from device */
-       err = usbnet_read_cmd(dev, USB_CDC_GET_MAX_DATAGRAM_SIZE,
-                             USB_TYPE_CLASS | USB_DIR_IN | USB_RECIP_INTERFACE,
-                             0, iface_no, &max_datagram_size, 2);
-       if (err < 0) {
-               dev_dbg(&dev->intf->dev, "GET_MAX_DATAGRAM_SIZE failed\n");
-               goto out;
-       }
+static int cdc_ncm_setup(struct usbnet *dev)
+{
+       struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
 
-       if (le16_to_cpu(max_datagram_size) == ctx->max_datagram_size)
-               goto out;
+       /* initialize basic device settings */
+       cdc_ncm_init(dev);
 
-       max_datagram_size = cpu_to_le16(ctx->max_datagram_size);
-       err = usbnet_write_cmd(dev, USB_CDC_SET_MAX_DATAGRAM_SIZE,
-                              USB_TYPE_CLASS | USB_DIR_OUT | USB_RECIP_INTERFACE,
-                              0, iface_no, &max_datagram_size, 2);
-       if (err < 0)
-               dev_dbg(&dev->intf->dev, "SET_MAX_DATAGRAM_SIZE failed\n");
-
-out:
-       /* set MTU to max supported by the device if necessary */
-       if (dev->net->mtu > ctx->max_datagram_size - eth_hlen)
-               dev->net->mtu = ctx->max_datagram_size - eth_hlen;
+       /* clamp rx_max and tx_max and inform device */
+       cdc_ncm_update_rxtx_max(dev, le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize),
+                               le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize));
 
-       /* do not exceed operater preferred MTU */
-       if (ctx->mbim_extended_desc) {
-               mbim_mtu = le16_to_cpu(ctx->mbim_extended_desc->wMTU);
-               if (mbim_mtu != 0 && mbim_mtu < dev->net->mtu)
-                       dev->net->mtu = mbim_mtu;
-       }
+       /* sanitize the modulus and remainder values */
+       cdc_ncm_fix_modulus(dev);
 
+       /* set max datagram size */
+       cdc_ncm_set_dgram_size(dev, cdc_ncm_max_dgram_size(dev));
        return 0;
 }
 
@@ -450,10 +498,21 @@ advance:
        }
 
        /* check if we got everything */
-       if (!ctx->data || (!ctx->mbim_desc && !ctx->ether_desc)) {
-               dev_dbg(&intf->dev, "CDC descriptors missing\n");
+       if (!ctx->data) {
+               dev_dbg(&intf->dev, "CDC Union missing and no IAD found\n");
                goto error;
        }
+       if (cdc_ncm_comm_intf_is_mbim(intf->cur_altsetting)) {
+               if (!ctx->mbim_desc) {
+                       dev_dbg(&intf->dev, "MBIM functional descriptor missing\n");
+                       goto error;
+               }
+       } else {
+               if (!ctx->ether_desc || !ctx->func_desc) {
+                       dev_dbg(&intf->dev, "NCM or ECM functional descriptors missing\n");
+                       goto error;
+               }
+       }
 
        /* claim data interface, if different from control */
        if (ctx->data != ctx->control) {