tty: n_smux: Add SMUX TTY Line Discipline Driver
Add new Serial Multiplexer (SMUX) driver.
This driver multiplexes multiple logical channels over a single
physical HSUART channel using the TTY Line Discipline framework.
This driver will be used in Fusion 4 for control plane, data plane
and DIAG traffic between Application processor and QSC modem.
Change-Id: Ibecf6cea872f5baf11fb93ded6124243a37a2085
Signed-off-by: Eric Holmberg <eholmber@codeaurora.org>
Signed-off-by: Angshuman Sarkar <angshuman@codeaurora.org>
Signed-off-by: Karthikeyan Ramasubramanian <kramasub@codeaurora.org>
diff --git a/drivers/tty/smux_private.h b/drivers/tty/smux_private.h
new file mode 100644
index 0000000..5ce8fb8
--- /dev/null
+++ b/drivers/tty/smux_private.h
@@ -0,0 +1,115 @@
+/* drivers/tty/smux_private.h
+ *
+ * Copyright (c) 2012, Code Aurora Forum. All rights reserved.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+#ifndef SMUX_PRIVATE_H
+#define SMUX_PRIVATE_H
+
+#define SMUX_MAX_PKT_SIZE 8192
+
+/* SMUX Protocol Characters */
+#define SMUX_MAGIC 0x33FC
+#define SMUX_MAGIC_WORD1 0xFC
+#define SMUX_MAGIC_WORD2 0x33
+#define SMUX_WAKEUP_REQ 0xFD
+#define SMUX_WAKEUP_ACK 0xFE
+
+/* Unit testing characters */
+#define SMUX_UT_ECHO_REQ 0xF0
+#define SMUX_UT_ECHO_ACK_OK 0xF1
+#define SMUX_UT_ECHO_ACK_FAIL 0xF2
+
+struct tty_struct;
+
+/* Packet header. */
+struct smux_hdr_t {
+ uint16_t magic;
+ uint8_t flags;
+ uint8_t cmd;
+ uint8_t pad_len;
+ uint8_t lcid;
+ uint16_t payload_len;
+};
+
+/* Internal packet structure. */
+struct smux_pkt_t {
+ struct smux_hdr_t hdr;
+ int allocated;
+ unsigned char *payload;
+ int free_payload;
+ struct list_head list;
+ void *priv;
+};
+
+/* SMUX Packet Commands */
+enum {
+ SMUX_CMD_DATA = 0x0,
+ SMUX_CMD_OPEN_LCH = 0x1,
+ SMUX_CMD_CLOSE_LCH = 0x2,
+ SMUX_CMD_STATUS = 0x3,
+ SMUX_CMD_PWR_CTL = 0x4,
+
+ SMUX_CMD_BYTE, /* for internal usage */
+ SMUX_NUM_COMMANDS
+};
+
+/* Open command flags */
+enum {
+ SMUX_CMD_OPEN_ACK = 1 << 0,
+ SMUX_CMD_OPEN_POWER_COLLAPSE = 1 << 1,
+ SMUX_CMD_OPEN_REMOTE_LOOPBACK = 1 << 2,
+};
+
+/* Close command flags */
+enum {
+ SMUX_CMD_CLOSE_ACK = 1 << 0,
+};
+
+/* Power command flags */
+enum {
+ SMUX_CMD_PWR_CTL_ACK = 1 << 0,
+ SMUX_CMD_PWR_CTL_SLEEP_REQ = 1 << 1,
+};
+
+/* Local logical channel states */
+enum {
+ SMUX_LCH_LOCAL_CLOSED,
+ SMUX_LCH_LOCAL_OPENING,
+ SMUX_LCH_LOCAL_OPENED,
+ SMUX_LCH_LOCAL_CLOSING,
+};
+
+/* Remote logical channel states */
+enum {
+ SMUX_LCH_REMOTE_CLOSED,
+ SMUX_LCH_REMOTE_OPENED,
+};
+
+
+int smux_assert_lch_id(uint32_t lcid);
+void smux_init_pkt(struct smux_pkt_t *pkt);
+struct smux_pkt_t *smux_alloc_pkt(void);
+int smux_alloc_pkt_payload(struct smux_pkt_t *pkt);
+void smux_free_pkt(struct smux_pkt_t *pkt);
+int smux_serialize(struct smux_pkt_t *pkt, char *out,
+ unsigned int *out_len);
+
+void smux_rx_state_machine(const unsigned char *data, int len, int flag);
+void smuxld_receive_buf(struct tty_struct *tty, const unsigned char *cp,
+ char *fp, int count);
+
+/* testing parameters */
+extern int smux_byte_loopback;
+extern int smux_simulate_wakeup_delay;
+
+#endif /* SMUX_PRIVATE_H */