net: cdc_ncm: adding MBIM support to ncm_setup

MBIM and NCM are very similar, so we can reuse most of the
setup and bind logic in cdc_ncm for CDC MBIM devices.  Handle
a few minor differences in ncm_setup.

Signed-off-by: Greg Suarez <gsuarez@smithmicro.com>
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/usb/cdc_ncm.c b/drivers/net/usb/cdc_ncm.c
index 32bdf542be1c6b3e1d30d703bcb594ad7c25eda2..77c6728d875fa7592adcd1e36ab2cc3fe957cb90 100644 (file)
--- a/drivers/net/usb/cdc_ncm.c
+++ b/drivers/net/usb/cdc_ncm.c
@@ -64,6 +64,9 @@
 /* Minimum value for MaxDatagramSize, ch. 6.2.9 */
 #define        CDC_NCM_MIN_DATAGRAM_SIZE               1514    /* bytes */
 
+/* Minimum value for MaxDatagramSize, ch. 8.1.3 */
+#define CDC_MBIM_MIN_DATAGRAM_SIZE              2048    /* bytes */
+
 #define        CDC_NCM_MIN_TX_PKT                      512     /* bytes */
 
 /* Default value for MaxDatagramSize */
@@ -98,6 +101,7 @@ struct cdc_ncm_ctx {
        struct tasklet_struct bh;
 
        const struct usb_cdc_ncm_desc *func_desc;
+       const struct usb_cdc_mbim_desc *mbim_desc;
        const struct usb_cdc_header_desc *header_desc;
        const struct usb_cdc_union_desc *union_desc;
        const struct usb_cdc_ether_desc *ether_desc;
@@ -158,7 +162,10 @@ static u8 cdc_ncm_setup(struct cdc_ncm_ctx *ctx)
        u8 flags;
        u8 iface_no;
        int err;
+       int eth_hlen;
        u16 ntb_fmt_supported;
+       u32 min_dgram_size;
+       u32 min_hdr_size;
 
        iface_no = ctx->control->cur_altsetting->desc.bInterfaceNumber;
 
@@ -184,10 +191,19 @@ static u8 cdc_ncm_setup(struct cdc_ncm_ctx *ctx)
        ctx->tx_max_datagrams = le16_to_cpu(ctx->ncm_parm.wNtbOutMaxDatagrams);
        ntb_fmt_supported = le16_to_cpu(ctx->ncm_parm.bmNtbFormatsSupported);
 
-       if (ctx->func_desc != NULL)
+       eth_hlen = ETH_HLEN;
+       min_dgram_size = CDC_NCM_MIN_DATAGRAM_SIZE;
+       min_hdr_size = CDC_NCM_MIN_HDR_SIZE;
+       if (ctx->mbim_desc != NULL) {
+               flags = ctx->mbim_desc->bmNetworkCapabilities;
+               eth_hlen = 0;
+               min_dgram_size = CDC_MBIM_MIN_DATAGRAM_SIZE;
+               min_hdr_size = 0;
+       } else if (ctx->func_desc != NULL) {
                flags = ctx->func_desc->bmNetworkCapabilities;
-       else
+       } else {
                flags = 0;
+       }
 
        pr_debug("dwNtbInMaxSize=%u dwNtbOutMaxSize=%u "
                 "wNdpOutPayloadRemainder=%u wNdpOutDivisor=%u "
@@ -237,7 +253,7 @@ size_err:
 
        /* verify maximum size of transmitted NTB in bytes */
        if ((ctx->tx_max <
-           (CDC_NCM_MIN_HDR_SIZE + CDC_NCM_MIN_DATAGRAM_SIZE)) ||
+           (min_hdr_size + min_dgram_size)) ||
            (ctx->tx_max > CDC_NCM_NTB_MAX_SIZE_TX)) {
                pr_debug("Using default maximum transmit length=%d\n",
                                                CDC_NCM_NTB_MAX_SIZE_TX);
@@ -279,8 +295,8 @@ size_err:
        }
 
        /* adjust TX-remainder according to NCM specification. */
-       ctx->tx_remainder = ((ctx->tx_remainder - ETH_HLEN) &
-                                               (ctx->tx_modulus - 1));
+       ctx->tx_remainder = ((ctx->tx_remainder - eth_hlen) &
+                            (ctx->tx_modulus - 1));
 
        /* additional configuration */
 
@@ -307,12 +323,18 @@ size_err:
                        pr_debug("Setting NTB format to 16-bit failed\n");
        }
 
-       ctx->max_datagram_size = CDC_NCM_MIN_DATAGRAM_SIZE;
+       ctx->max_datagram_size = min_dgram_size;
 
        /* set Max Datagram Size (MTU) */
        if (flags & USB_CDC_NCM_NCAP_MAX_DATAGRAM_SIZE) {
                __le16 *max_datagram_size;
-               u16 eth_max_sz = le16_to_cpu(ctx->ether_desc->wMaxSegmentSize);
+               u16 eth_max_sz;
+               if (ctx->ether_desc != NULL)
+                       eth_max_sz = le16_to_cpu(ctx->ether_desc->wMaxSegmentSize);
+               else if (ctx->mbim_desc != NULL)
+                       eth_max_sz = le16_to_cpu(ctx->mbim_desc->wMaxSegmentSize);
+               else
+                       goto max_dgram_err;
 
                max_datagram_size = kzalloc(sizeof(*max_datagram_size),
                                GFP_KERNEL);
@@ -329,7 +351,7 @@ size_err:
                                2, 1000);
                if (err < 0) {
                        pr_debug("GET_MAX_DATAGRAM_SIZE failed, use size=%u\n",
-                                               CDC_NCM_MIN_DATAGRAM_SIZE);
+                                min_dgram_size);
                } else {
                        ctx->max_datagram_size =
                                le16_to_cpu(*max_datagram_size);
@@ -338,12 +360,10 @@ size_err:
                                        ctx->max_datagram_size = eth_max_sz;
 
                        if (ctx->max_datagram_size > CDC_NCM_MAX_DATAGRAM_SIZE)
-                               ctx->max_datagram_size =
-                                               CDC_NCM_MAX_DATAGRAM_SIZE;
+                               ctx->max_datagram_size = CDC_NCM_MAX_DATAGRAM_SIZE;
 
-                       if (ctx->max_datagram_size < CDC_NCM_MIN_DATAGRAM_SIZE)
-                               ctx->max_datagram_size =
-                                       CDC_NCM_MIN_DATAGRAM_SIZE;
+                       if (ctx->max_datagram_size < min_dgram_size)
+                               ctx->max_datagram_size = min_dgram_size;
 
                        /* if value changed, update device */
                        if (ctx->max_datagram_size !=
@@ -364,8 +384,8 @@ size_err:
        }
 
 max_dgram_err:
-       if (ctx->netdev->mtu != (ctx->max_datagram_size - ETH_HLEN))
-               ctx->netdev->mtu = ctx->max_datagram_size - ETH_HLEN;
+       if (ctx->netdev->mtu != (ctx->max_datagram_size - eth_hlen))
+               ctx->netdev->mtu = ctx->max_datagram_size - eth_hlen;
 
        return 0;
 }