usb: gadget: ncm: make global variable ndp*_opts read only

There is ndp16_opts and ndp32_opts which are both global and only one
member is ever written. This patch makes the variable read-only and
moves the one member that is ever written into the private struct f_ncm.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Felipe Balbi <balbi@ti.com>

diff --git a/drivers/usb/gadget/f_ncm.c b/drivers/usb/gadget/f_ncm.c
index 6c8362f..5e7557e 100644 (file)
--- a/drivers/usb/gadget/f_ncm.c
+++ b/drivers/usb/gadget/f_ncm.c
@@ -56,8 +56,9 @@ struct f_ncm {
        u8                              notify_state;
        bool                            is_open;
 
-       struct ndp_parser_opts          *parser_opts;
+       const struct ndp_parser_opts    *parser_opts;
        bool                            is_crc;
+       u32                             ndp_sign;
 
        /*
         * for notification, it is accessed from both
@@ -390,8 +391,8 @@ struct ndp_parser_opts {
                .next_fp_index = 2,                             \
        }
 
-static struct ndp_parser_opts ndp16_opts = INIT_NDP16_OPTS;
-static struct ndp_parser_opts ndp32_opts = INIT_NDP32_OPTS;
+static const struct ndp_parser_opts ndp16_opts = INIT_NDP16_OPTS;
+static const struct ndp_parser_opts ndp32_opts = INIT_NDP32_OPTS;
 
 static inline void put_ncm(__le16 **p, unsigned size, unsigned val)
 {
@@ -732,8 +733,7 @@ static int ncm_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
                default:
                        goto invalid;
                }
-               ncm->parser_opts->ndp_sign &= ~NCM_NDP_HDR_CRC_MASK;
-               ncm->parser_opts->ndp_sign |= ndp_hdr_crc;
+               ncm->ndp_sign = ncm->parser_opts->ndp_sign | ndp_hdr_crc;
                value = 0;
                break;
        }
@@ -875,7 +875,7 @@ static struct sk_buff *ncm_wrap_ntb(struct gether *port,
        int             ndp_align;
        int             ndp_pad;
        unsigned        max_size = ncm->port.fixed_in_len;
-       struct ndp_parser_opts *opts = ncm->parser_opts;
+       const struct ndp_parser_opts *opts = ncm->parser_opts;
        unsigned        crc_len = ncm->is_crc ? sizeof(uint32_t) : 0;
 
        div = le16_to_cpu(ntb_parameters.wNdpInDivisor);
@@ -921,7 +921,7 @@ static struct sk_buff *ncm_wrap_ntb(struct gether *port,
        tmp = (void *)tmp + ndp_pad;
 
        /* NDP */
-       put_unaligned_le32(opts->ndp_sign, tmp); /* dwSignature */
+       put_unaligned_le32(ncm->ndp_sign, tmp); /* dwSignature */
        tmp += 2;
        /* wLength */
        put_unaligned_le16(ncb_len - opts->nth_size - pad, tmp++);
@@ -965,7 +965,7 @@ static int ncm_unwrap_ntb(struct gether *port,
        struct sk_buff  *skb2;
        int             ret = -EINVAL;
        unsigned        max_size = le32_to_cpu(ntb_parameters.dwNtbOutMaxSize);
-       struct ndp_parser_opts *opts = ncm->parser_opts;
+       const struct ndp_parser_opts *opts = ncm->parser_opts;
        unsigned        crc_len = ncm->is_crc ? sizeof(uint32_t) : 0;
        int             dgram_counter;
 
@@ -1002,7 +1002,7 @@ static int ncm_unwrap_ntb(struct gether *port,
 
        /* walk through NDP */
        tmp = ((void *)skb->data) + index;
-       if (get_unaligned_le32(tmp) != opts->ndp_sign) {
+       if (get_unaligned_le32(tmp) != ncm->ndp_sign) {
                INFO(port->func.config->cdev, "Wrong NDP SIGN\n");
                goto err;
        }