^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0-only
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * shdlc Link Layer Control
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * Copyright (C) 2012 Intel Corporation. All rights reserved.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) #define pr_fmt(fmt) "shdlc: %s: " fmt, __func__
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/types.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/sched.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/wait.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/slab.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include <linux/skbuff.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #include "llc.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) enum shdlc_state {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) SHDLC_DISCONNECTED = 0,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) SHDLC_CONNECTING = 1,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) SHDLC_NEGOTIATING = 2,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) SHDLC_HALF_CONNECTED = 3,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) SHDLC_CONNECTED = 4
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) struct llc_shdlc {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) struct nfc_hci_dev *hdev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) xmit_to_drv_t xmit_to_drv;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) rcv_to_hci_t rcv_to_hci;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) struct mutex state_mutex;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) enum shdlc_state state;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) int hard_fault;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) wait_queue_head_t *connect_wq;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) int connect_tries;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) int connect_result;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) struct timer_list connect_timer;/* aka T3 in spec 10.6.1 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) u8 w; /* window size */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) bool srej_support;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) struct timer_list t1_timer; /* send ack timeout */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) bool t1_active;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) struct timer_list t2_timer; /* guard/retransmit timeout */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) bool t2_active;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) int ns; /* next seq num for send */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) int nr; /* next expected seq num for receive */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) int dnr; /* oldest sent unacked seq num */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) struct sk_buff_head rcv_q;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) struct sk_buff_head send_q;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) bool rnr; /* other side is not ready to receive */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) struct sk_buff_head ack_pending_q;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) struct work_struct sm_work;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) int tx_headroom;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) int tx_tailroom;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) llc_failure_t llc_failure;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) #define SHDLC_LLC_HEAD_ROOM 2
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) #define SHDLC_MAX_WINDOW 4
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) #define SHDLC_SREJ_SUPPORT false
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) #define SHDLC_CONTROL_HEAD_MASK 0xe0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) #define SHDLC_CONTROL_HEAD_I 0x80
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) #define SHDLC_CONTROL_HEAD_I2 0xa0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) #define SHDLC_CONTROL_HEAD_S 0xc0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) #define SHDLC_CONTROL_HEAD_U 0xe0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) #define SHDLC_CONTROL_NS_MASK 0x38
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) #define SHDLC_CONTROL_NR_MASK 0x07
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) #define SHDLC_CONTROL_TYPE_MASK 0x18
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) #define SHDLC_CONTROL_M_MASK 0x1f
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) enum sframe_type {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) S_FRAME_RR = 0x00,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) S_FRAME_REJ = 0x01,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) S_FRAME_RNR = 0x02,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) S_FRAME_SREJ = 0x03
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) enum uframe_modifier {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) U_FRAME_UA = 0x06,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) U_FRAME_RSET = 0x19
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) #define SHDLC_CONNECT_VALUE_MS 5
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) #define SHDLC_T1_VALUE_MS(w) ((5 * w) / 4)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) #define SHDLC_T2_VALUE_MS 300
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) #define SHDLC_DUMP_SKB(info, skb) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) do { \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) pr_debug("%s:\n", info); \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) print_hex_dump(KERN_DEBUG, "shdlc: ", DUMP_PREFIX_OFFSET, \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) 16, 1, skb->data, skb->len, 0); \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) } while (0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) /* checks x < y <= z modulo 8 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) static bool llc_shdlc_x_lt_y_lteq_z(int x, int y, int z)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) if (x < z)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) return ((x < y) && (y <= z)) ? true : false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) return ((y > x) || (y <= z)) ? true : false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) /* checks x <= y < z modulo 8 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) static bool llc_shdlc_x_lteq_y_lt_z(int x, int y, int z)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) if (x <= z)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) return ((x <= y) && (y < z)) ? true : false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) else /* x > z -> z+8 > x */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) return ((y >= x) || (y < z)) ? true : false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) static struct sk_buff *llc_shdlc_alloc_skb(struct llc_shdlc *shdlc,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) int payload_len)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) struct sk_buff *skb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) skb = alloc_skb(shdlc->tx_headroom + SHDLC_LLC_HEAD_ROOM +
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) shdlc->tx_tailroom + payload_len, GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) if (skb)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) skb_reserve(skb, shdlc->tx_headroom + SHDLC_LLC_HEAD_ROOM);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) return skb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) /* immediately sends an S frame. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) static int llc_shdlc_send_s_frame(struct llc_shdlc *shdlc,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) enum sframe_type sframe_type, int nr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) int r;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) struct sk_buff *skb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) pr_debug("sframe_type=%d nr=%d\n", sframe_type, nr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) skb = llc_shdlc_alloc_skb(shdlc, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) if (skb == NULL)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) *(u8 *)skb_push(skb, 1) = SHDLC_CONTROL_HEAD_S | (sframe_type << 3) | nr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) r = shdlc->xmit_to_drv(shdlc->hdev, skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) kfree_skb(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) return r;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) /* immediately sends an U frame. skb may contain optional payload */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) static int llc_shdlc_send_u_frame(struct llc_shdlc *shdlc,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) struct sk_buff *skb,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) enum uframe_modifier uframe_modifier)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) int r;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) pr_debug("uframe_modifier=%d\n", uframe_modifier);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) *(u8 *)skb_push(skb, 1) = SHDLC_CONTROL_HEAD_U | uframe_modifier;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) r = shdlc->xmit_to_drv(shdlc->hdev, skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) kfree_skb(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) return r;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) * Free ack_pending frames until y_nr - 1, and reset t2 according to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) * the remaining oldest ack_pending frame sent time
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) static void llc_shdlc_reset_t2(struct llc_shdlc *shdlc, int y_nr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) struct sk_buff *skb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) int dnr = shdlc->dnr; /* MUST initially be < y_nr */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) pr_debug("release ack pending up to frame %d excluded\n", y_nr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) while (dnr != y_nr) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) pr_debug("release ack pending frame %d\n", dnr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) skb = skb_dequeue(&shdlc->ack_pending_q);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) kfree_skb(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) dnr = (dnr + 1) % 8;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) if (skb_queue_empty(&shdlc->ack_pending_q)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) if (shdlc->t2_active) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) del_timer_sync(&shdlc->t2_timer);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) shdlc->t2_active = false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) pr_debug
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) ("All sent frames acked. Stopped T2(retransmit)\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) skb = skb_peek(&shdlc->ack_pending_q);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) mod_timer(&shdlc->t2_timer, *(unsigned long *)skb->cb +
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) msecs_to_jiffies(SHDLC_T2_VALUE_MS));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) shdlc->t2_active = true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) pr_debug
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) ("Start T2(retransmit) for remaining unacked sent frames\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) * Receive validated frames from lower layer. skb contains HCI payload only.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) * Handle according to algorithm at spec:10.8.2
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) static void llc_shdlc_rcv_i_frame(struct llc_shdlc *shdlc,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) struct sk_buff *skb, int ns, int nr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226) int x_ns = ns;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227) int y_nr = nr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229) pr_debug("recvd I-frame %d, remote waiting frame %d\n", ns, nr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231) if (shdlc->state != SHDLC_CONNECTED)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232) goto exit;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) if (x_ns != shdlc->nr) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) llc_shdlc_send_s_frame(shdlc, S_FRAME_REJ, shdlc->nr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236) goto exit;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) if (shdlc->t1_active == false) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240) shdlc->t1_active = true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241) mod_timer(&shdlc->t1_timer, jiffies +
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242) msecs_to_jiffies(SHDLC_T1_VALUE_MS(shdlc->w)));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243) pr_debug("(re)Start T1(send ack)\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246) if (skb->len) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247) shdlc->rcv_to_hci(shdlc->hdev, skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248) skb = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251) shdlc->nr = (shdlc->nr + 1) % 8;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253) if (llc_shdlc_x_lt_y_lteq_z(shdlc->dnr, y_nr, shdlc->ns)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254) llc_shdlc_reset_t2(shdlc, y_nr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256) shdlc->dnr = y_nr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259) exit:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260) kfree_skb(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) static void llc_shdlc_rcv_ack(struct llc_shdlc *shdlc, int y_nr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265) pr_debug("remote acked up to frame %d excluded\n", y_nr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267) if (llc_shdlc_x_lt_y_lteq_z(shdlc->dnr, y_nr, shdlc->ns)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268) llc_shdlc_reset_t2(shdlc, y_nr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269) shdlc->dnr = y_nr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273) static void llc_shdlc_requeue_ack_pending(struct llc_shdlc *shdlc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275) struct sk_buff *skb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277) pr_debug("ns reset to %d\n", shdlc->dnr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279) while ((skb = skb_dequeue_tail(&shdlc->ack_pending_q))) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280) skb_pull(skb, 1); /* remove control field */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281) skb_queue_head(&shdlc->send_q, skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283) shdlc->ns = shdlc->dnr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286) static void llc_shdlc_rcv_rej(struct llc_shdlc *shdlc, int y_nr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288) struct sk_buff *skb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290) pr_debug("remote asks retransmission from frame %d\n", y_nr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292) if (llc_shdlc_x_lteq_y_lt_z(shdlc->dnr, y_nr, shdlc->ns)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293) if (shdlc->t2_active) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 294) del_timer_sync(&shdlc->t2_timer);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 295) shdlc->t2_active = false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 296) pr_debug("Stopped T2(retransmit)\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 297) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 298)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 299) if (shdlc->dnr != y_nr) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 300) while ((shdlc->dnr = ((shdlc->dnr + 1) % 8)) != y_nr) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 301) skb = skb_dequeue(&shdlc->ack_pending_q);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 302) kfree_skb(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 303) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 304) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 305)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 306) llc_shdlc_requeue_ack_pending(shdlc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 307) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 308) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 309)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 310) /* See spec RR:10.8.3 REJ:10.8.4 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 311) static void llc_shdlc_rcv_s_frame(struct llc_shdlc *shdlc,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 312) enum sframe_type s_frame_type, int nr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 313) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 314) struct sk_buff *skb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 315)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 316) if (shdlc->state != SHDLC_CONNECTED)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 317) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 318)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 319) switch (s_frame_type) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 320) case S_FRAME_RR:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 321) llc_shdlc_rcv_ack(shdlc, nr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 322) if (shdlc->rnr == true) { /* see SHDLC 10.7.7 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 323) shdlc->rnr = false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 324) if (shdlc->send_q.qlen == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 325) skb = llc_shdlc_alloc_skb(shdlc, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 326) if (skb)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 327) skb_queue_tail(&shdlc->send_q, skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 328) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 329) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 330) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 331) case S_FRAME_REJ:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 332) llc_shdlc_rcv_rej(shdlc, nr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 333) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 334) case S_FRAME_RNR:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 335) llc_shdlc_rcv_ack(shdlc, nr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 336) shdlc->rnr = true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 337) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 338) default:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 339) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 340) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 341) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 342)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 343) static void llc_shdlc_connect_complete(struct llc_shdlc *shdlc, int r)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 344) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 345) pr_debug("result=%d\n", r);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 346)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 347) del_timer_sync(&shdlc->connect_timer);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 348)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 349) if (r == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 350) shdlc->ns = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 351) shdlc->nr = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 352) shdlc->dnr = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 353)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 354) shdlc->state = SHDLC_HALF_CONNECTED;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 355) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 356) shdlc->state = SHDLC_DISCONNECTED;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 357) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 358)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 359) shdlc->connect_result = r;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 360)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 361) wake_up(shdlc->connect_wq);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 362) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 363)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 364) static int llc_shdlc_connect_initiate(struct llc_shdlc *shdlc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 365) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 366) struct sk_buff *skb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 367)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 368) pr_debug("\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 369)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 370) skb = llc_shdlc_alloc_skb(shdlc, 2);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 371) if (skb == NULL)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 372) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 373)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 374) skb_put_u8(skb, SHDLC_MAX_WINDOW);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 375) skb_put_u8(skb, SHDLC_SREJ_SUPPORT ? 1 : 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 376)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 377) return llc_shdlc_send_u_frame(shdlc, skb, U_FRAME_RSET);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 378) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 379)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 380) static int llc_shdlc_connect_send_ua(struct llc_shdlc *shdlc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 381) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 382) struct sk_buff *skb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 383)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 384) pr_debug("\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 385)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 386) skb = llc_shdlc_alloc_skb(shdlc, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 387) if (skb == NULL)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 388) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 389)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 390) return llc_shdlc_send_u_frame(shdlc, skb, U_FRAME_UA);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 391) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 392)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 393) static void llc_shdlc_rcv_u_frame(struct llc_shdlc *shdlc,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 394) struct sk_buff *skb,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 395) enum uframe_modifier u_frame_modifier)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 396) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 397) u8 w = SHDLC_MAX_WINDOW;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 398) bool srej_support = SHDLC_SREJ_SUPPORT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 399) int r;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 400)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 401) pr_debug("u_frame_modifier=%d\n", u_frame_modifier);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 402)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 403) switch (u_frame_modifier) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 404) case U_FRAME_RSET:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 405) switch (shdlc->state) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 406) case SHDLC_NEGOTIATING:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 407) case SHDLC_CONNECTING:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 408) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 409) * We sent RSET, but chip wants to negociate or we
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 410) * got RSET before we managed to send out our.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 411) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 412) if (skb->len > 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 413) w = skb->data[0];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 414)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 415) if (skb->len > 1)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 416) srej_support = skb->data[1] & 0x01 ? true :
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 417) false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 418)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 419) if ((w <= SHDLC_MAX_WINDOW) &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 420) (SHDLC_SREJ_SUPPORT || (srej_support == false))) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 421) shdlc->w = w;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 422) shdlc->srej_support = srej_support;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 423) r = llc_shdlc_connect_send_ua(shdlc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 424) llc_shdlc_connect_complete(shdlc, r);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 425) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 426) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 427) case SHDLC_HALF_CONNECTED:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 428) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 429) * Chip resent RSET due to its timeout - Ignote it
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 430) * as we already sent UA.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 431) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 432) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 433) case SHDLC_CONNECTED:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 434) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 435) * Chip wants to reset link. This is unexpected and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 436) * unsupported.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 437) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 438) shdlc->hard_fault = -ECONNRESET;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 439) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 440) default:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 441) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 442) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 443) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 444) case U_FRAME_UA:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 445) if ((shdlc->state == SHDLC_CONNECTING &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 446) shdlc->connect_tries > 0) ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 447) (shdlc->state == SHDLC_NEGOTIATING)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 448) llc_shdlc_connect_complete(shdlc, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 449) shdlc->state = SHDLC_CONNECTED;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 450) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 451) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 452) default:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 453) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 454) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 455)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 456) kfree_skb(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 457) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 458)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 459) static void llc_shdlc_handle_rcv_queue(struct llc_shdlc *shdlc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 460) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 461) struct sk_buff *skb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 462) u8 control;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 463) int nr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 464) int ns;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 465) enum sframe_type s_frame_type;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 466) enum uframe_modifier u_frame_modifier;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 467)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 468) if (shdlc->rcv_q.qlen)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 469) pr_debug("rcvQlen=%d\n", shdlc->rcv_q.qlen);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 470)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 471) while ((skb = skb_dequeue(&shdlc->rcv_q)) != NULL) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 472) control = skb->data[0];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 473) skb_pull(skb, 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 474) switch (control & SHDLC_CONTROL_HEAD_MASK) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 475) case SHDLC_CONTROL_HEAD_I:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 476) case SHDLC_CONTROL_HEAD_I2:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 477) if (shdlc->state == SHDLC_HALF_CONNECTED)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 478) shdlc->state = SHDLC_CONNECTED;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 479)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 480) ns = (control & SHDLC_CONTROL_NS_MASK) >> 3;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 481) nr = control & SHDLC_CONTROL_NR_MASK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 482) llc_shdlc_rcv_i_frame(shdlc, skb, ns, nr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 483) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 484) case SHDLC_CONTROL_HEAD_S:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 485) if (shdlc->state == SHDLC_HALF_CONNECTED)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 486) shdlc->state = SHDLC_CONNECTED;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 487)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 488) s_frame_type = (control & SHDLC_CONTROL_TYPE_MASK) >> 3;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 489) nr = control & SHDLC_CONTROL_NR_MASK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 490) llc_shdlc_rcv_s_frame(shdlc, s_frame_type, nr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 491) kfree_skb(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 492) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 493) case SHDLC_CONTROL_HEAD_U:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 494) u_frame_modifier = control & SHDLC_CONTROL_M_MASK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 495) llc_shdlc_rcv_u_frame(shdlc, skb, u_frame_modifier);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 496) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 497) default:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 498) pr_err("UNKNOWN Control=%d\n", control);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 499) kfree_skb(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 500) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 501) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 502) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 503) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 504)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 505) static int llc_shdlc_w_used(int ns, int dnr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 506) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 507) int unack_count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 508)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 509) if (dnr <= ns)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 510) unack_count = ns - dnr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 511) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 512) unack_count = 8 - dnr + ns;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 513)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 514) return unack_count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 515) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 516)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 517) /* Send frames according to algorithm at spec:10.8.1 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 518) static void llc_shdlc_handle_send_queue(struct llc_shdlc *shdlc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 519) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 520) struct sk_buff *skb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 521) int r;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 522) unsigned long time_sent;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 523)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 524) if (shdlc->send_q.qlen)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 525) pr_debug
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 526) ("sendQlen=%d ns=%d dnr=%d rnr=%s w_room=%d unackQlen=%d\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 527) shdlc->send_q.qlen, shdlc->ns, shdlc->dnr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 528) shdlc->rnr == false ? "false" : "true",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 529) shdlc->w - llc_shdlc_w_used(shdlc->ns, shdlc->dnr),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 530) shdlc->ack_pending_q.qlen);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 531)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 532) while (shdlc->send_q.qlen && shdlc->ack_pending_q.qlen < shdlc->w &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 533) (shdlc->rnr == false)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 534)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 535) if (shdlc->t1_active) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 536) del_timer_sync(&shdlc->t1_timer);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 537) shdlc->t1_active = false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 538) pr_debug("Stopped T1(send ack)\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 539) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 540)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 541) skb = skb_dequeue(&shdlc->send_q);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 542)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 543) *(u8 *)skb_push(skb, 1) = SHDLC_CONTROL_HEAD_I | (shdlc->ns << 3) |
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 544) shdlc->nr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 545)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 546) pr_debug("Sending I-Frame %d, waiting to rcv %d\n", shdlc->ns,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 547) shdlc->nr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 548) SHDLC_DUMP_SKB("shdlc frame written", skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 549)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 550) r = shdlc->xmit_to_drv(shdlc->hdev, skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 551) if (r < 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 552) shdlc->hard_fault = r;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 553) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 554) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 555)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 556) shdlc->ns = (shdlc->ns + 1) % 8;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 557)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 558) time_sent = jiffies;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 559) *(unsigned long *)skb->cb = time_sent;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 560)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 561) skb_queue_tail(&shdlc->ack_pending_q, skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 562)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 563) if (shdlc->t2_active == false) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 564) shdlc->t2_active = true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 565) mod_timer(&shdlc->t2_timer, time_sent +
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 566) msecs_to_jiffies(SHDLC_T2_VALUE_MS));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 567) pr_debug("Started T2 (retransmit)\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 568) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 569) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 570) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 571)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 572) static void llc_shdlc_connect_timeout(struct timer_list *t)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 573) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 574) struct llc_shdlc *shdlc = from_timer(shdlc, t, connect_timer);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 575)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 576) pr_debug("\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 577)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 578) schedule_work(&shdlc->sm_work);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 579) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 580)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 581) static void llc_shdlc_t1_timeout(struct timer_list *t)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 582) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 583) struct llc_shdlc *shdlc = from_timer(shdlc, t, t1_timer);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 584)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 585) pr_debug("SoftIRQ: need to send ack\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 586)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 587) schedule_work(&shdlc->sm_work);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 588) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 589)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 590) static void llc_shdlc_t2_timeout(struct timer_list *t)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 591) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 592) struct llc_shdlc *shdlc = from_timer(shdlc, t, t2_timer);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 593)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 594) pr_debug("SoftIRQ: need to retransmit\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 595)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 596) schedule_work(&shdlc->sm_work);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 597) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 598)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 599) static void llc_shdlc_sm_work(struct work_struct *work)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 600) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 601) struct llc_shdlc *shdlc = container_of(work, struct llc_shdlc, sm_work);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 602) int r;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 603)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 604) pr_debug("\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 605)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 606) mutex_lock(&shdlc->state_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 607)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 608) switch (shdlc->state) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 609) case SHDLC_DISCONNECTED:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 610) skb_queue_purge(&shdlc->rcv_q);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 611) skb_queue_purge(&shdlc->send_q);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 612) skb_queue_purge(&shdlc->ack_pending_q);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 613) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 614) case SHDLC_CONNECTING:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 615) if (shdlc->hard_fault) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 616) llc_shdlc_connect_complete(shdlc, shdlc->hard_fault);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 617) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 618) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 619)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 620) if (shdlc->connect_tries++ < 5)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 621) r = llc_shdlc_connect_initiate(shdlc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 622) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 623) r = -ETIME;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 624) if (r < 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 625) llc_shdlc_connect_complete(shdlc, r);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 626) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 627) mod_timer(&shdlc->connect_timer, jiffies +
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 628) msecs_to_jiffies(SHDLC_CONNECT_VALUE_MS));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 629)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 630) shdlc->state = SHDLC_NEGOTIATING;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 631) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 632) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 633) case SHDLC_NEGOTIATING:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 634) if (timer_pending(&shdlc->connect_timer) == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 635) shdlc->state = SHDLC_CONNECTING;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 636) schedule_work(&shdlc->sm_work);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 637) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 638)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 639) llc_shdlc_handle_rcv_queue(shdlc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 640)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 641) if (shdlc->hard_fault) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 642) llc_shdlc_connect_complete(shdlc, shdlc->hard_fault);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 643) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 644) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 645) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 646) case SHDLC_HALF_CONNECTED:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 647) case SHDLC_CONNECTED:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 648) llc_shdlc_handle_rcv_queue(shdlc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 649) llc_shdlc_handle_send_queue(shdlc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 650)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 651) if (shdlc->t1_active && timer_pending(&shdlc->t1_timer) == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 652) pr_debug
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 653) ("Handle T1(send ack) elapsed (T1 now inactive)\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 654)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 655) shdlc->t1_active = false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 656) r = llc_shdlc_send_s_frame(shdlc, S_FRAME_RR,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 657) shdlc->nr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 658) if (r < 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 659) shdlc->hard_fault = r;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 660) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 661)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 662) if (shdlc->t2_active && timer_pending(&shdlc->t2_timer) == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 663) pr_debug
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 664) ("Handle T2(retransmit) elapsed (T2 inactive)\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 665)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 666) shdlc->t2_active = false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 667)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 668) llc_shdlc_requeue_ack_pending(shdlc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 669) llc_shdlc_handle_send_queue(shdlc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 670) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 671)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 672) if (shdlc->hard_fault)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 673) shdlc->llc_failure(shdlc->hdev, shdlc->hard_fault);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 674) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 675) default:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 676) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 677) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 678) mutex_unlock(&shdlc->state_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 679) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 680)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 681) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 682) * Called from syscall context to establish shdlc link. Sleeps until
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 683) * link is ready or failure.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 684) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 685) static int llc_shdlc_connect(struct llc_shdlc *shdlc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 686) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 687) DECLARE_WAIT_QUEUE_HEAD_ONSTACK(connect_wq);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 688)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 689) pr_debug("\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 690)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 691) mutex_lock(&shdlc->state_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 692)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 693) shdlc->state = SHDLC_CONNECTING;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 694) shdlc->connect_wq = &connect_wq;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 695) shdlc->connect_tries = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 696) shdlc->connect_result = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 697)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 698) mutex_unlock(&shdlc->state_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 699)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 700) schedule_work(&shdlc->sm_work);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 701)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 702) wait_event(connect_wq, shdlc->connect_result != 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 703)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 704) return shdlc->connect_result;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 705) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 706)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 707) static void llc_shdlc_disconnect(struct llc_shdlc *shdlc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 708) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 709) pr_debug("\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 710)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 711) mutex_lock(&shdlc->state_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 712)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 713) shdlc->state = SHDLC_DISCONNECTED;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 714)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 715) mutex_unlock(&shdlc->state_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 716)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 717) schedule_work(&shdlc->sm_work);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 718) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 719)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 720) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 721) * Receive an incoming shdlc frame. Frame has already been crc-validated.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 722) * skb contains only LLC header and payload.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 723) * If skb == NULL, it is a notification that the link below is dead.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 724) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 725) static void llc_shdlc_recv_frame(struct llc_shdlc *shdlc, struct sk_buff *skb)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 726) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 727) if (skb == NULL) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 728) pr_err("NULL Frame -> link is dead\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 729) shdlc->hard_fault = -EREMOTEIO;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 730) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 731) SHDLC_DUMP_SKB("incoming frame", skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 732) skb_queue_tail(&shdlc->rcv_q, skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 733) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 734)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 735) schedule_work(&shdlc->sm_work);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 736) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 737)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 738) static void *llc_shdlc_init(struct nfc_hci_dev *hdev, xmit_to_drv_t xmit_to_drv,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 739) rcv_to_hci_t rcv_to_hci, int tx_headroom,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 740) int tx_tailroom, int *rx_headroom, int *rx_tailroom,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 741) llc_failure_t llc_failure)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 742) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 743) struct llc_shdlc *shdlc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 744)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 745) *rx_headroom = SHDLC_LLC_HEAD_ROOM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 746) *rx_tailroom = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 747)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 748) shdlc = kzalloc(sizeof(struct llc_shdlc), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 749) if (shdlc == NULL)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 750) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 751)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 752) mutex_init(&shdlc->state_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 753) shdlc->state = SHDLC_DISCONNECTED;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 754)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 755) timer_setup(&shdlc->connect_timer, llc_shdlc_connect_timeout, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 756) timer_setup(&shdlc->t1_timer, llc_shdlc_t1_timeout, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 757) timer_setup(&shdlc->t2_timer, llc_shdlc_t2_timeout, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 758)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 759) shdlc->w = SHDLC_MAX_WINDOW;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 760) shdlc->srej_support = SHDLC_SREJ_SUPPORT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 761)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 762) skb_queue_head_init(&shdlc->rcv_q);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 763) skb_queue_head_init(&shdlc->send_q);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 764) skb_queue_head_init(&shdlc->ack_pending_q);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 765)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 766) INIT_WORK(&shdlc->sm_work, llc_shdlc_sm_work);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 767)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 768) shdlc->hdev = hdev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 769) shdlc->xmit_to_drv = xmit_to_drv;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 770) shdlc->rcv_to_hci = rcv_to_hci;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 771) shdlc->tx_headroom = tx_headroom;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 772) shdlc->tx_tailroom = tx_tailroom;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 773) shdlc->llc_failure = llc_failure;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 774)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 775) return shdlc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 776) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 777)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 778) static void llc_shdlc_deinit(struct nfc_llc *llc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 779) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 780) struct llc_shdlc *shdlc = nfc_llc_get_data(llc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 781)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 782) skb_queue_purge(&shdlc->rcv_q);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 783) skb_queue_purge(&shdlc->send_q);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 784) skb_queue_purge(&shdlc->ack_pending_q);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 785)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 786) kfree(shdlc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 787) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 788)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 789) static int llc_shdlc_start(struct nfc_llc *llc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 790) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 791) struct llc_shdlc *shdlc = nfc_llc_get_data(llc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 792)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 793) return llc_shdlc_connect(shdlc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 794) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 795)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 796) static int llc_shdlc_stop(struct nfc_llc *llc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 797) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 798) struct llc_shdlc *shdlc = nfc_llc_get_data(llc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 799)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 800) llc_shdlc_disconnect(shdlc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 801)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 802) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 803) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 804)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 805) static void llc_shdlc_rcv_from_drv(struct nfc_llc *llc, struct sk_buff *skb)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 806) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 807) struct llc_shdlc *shdlc = nfc_llc_get_data(llc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 808)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 809) llc_shdlc_recv_frame(shdlc, skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 810) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 811)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 812) static int llc_shdlc_xmit_from_hci(struct nfc_llc *llc, struct sk_buff *skb)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 813) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 814) struct llc_shdlc *shdlc = nfc_llc_get_data(llc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 815)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 816) skb_queue_tail(&shdlc->send_q, skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 817)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 818) schedule_work(&shdlc->sm_work);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 819)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 820) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 821) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 822)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 823) static struct nfc_llc_ops llc_shdlc_ops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 824) .init = llc_shdlc_init,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 825) .deinit = llc_shdlc_deinit,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 826) .start = llc_shdlc_start,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 827) .stop = llc_shdlc_stop,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 828) .rcv_from_drv = llc_shdlc_rcv_from_drv,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 829) .xmit_from_hci = llc_shdlc_xmit_from_hci,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 830) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 831)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 832) int nfc_llc_shdlc_register(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 833) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 834) return nfc_llc_register(LLC_SHDLC_NAME, &llc_shdlc_ops);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 835) }
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
3 Commits
0 Branches
0 Tags