include/linux/ti_wilink_st.h

0001 /* SPDX-License-Identifier: GPL-2.0-only */
0002 /*
0003  *  Shared Transport Header file
0004  *  To be included by the protocol stack drivers for
0005  *  Texas Instruments BT,FM and GPS combo chip drivers
0006  *  and also serves the sub-modules of the shared transport driver.
0007  *
0008  *  Copyright (C) 2009-2010 Texas Instruments
0009  *  Author: Pavan Savoy <pavan_savoy@ti.com>
0010  */
0011
0012 #ifndef TI_WILINK_ST_H
0013 #define TI_WILINK_ST_H
0014
0015 #include <linux/skbuff.h>
0016
0017 /**
0018  * enum proto-type - The protocol on WiLink chips which share a
0019  *  common physical interface like UART.
0020  */
0021 enum proto_type {
0022     ST_BT,
0023     ST_FM,
0024     ST_GPS,
0025     ST_MAX_CHANNELS = 16,
0026 };
0027
0028 /**
0029  * struct st_proto_s - Per Protocol structure from BT/FM/GPS to ST
0030  * @type: type of the protocol being registered among the
0031  *  available proto_type(BT, FM, GPS the protocol which share TTY).
0032  * @recv: the receiver callback pointing to a function in the
0033  *  protocol drivers called by the ST driver upon receiving
0034  *  relevant data.
0035  * @match_packet: reserved for future use, to make ST more generic
0036  * @reg_complete_cb: callback handler pointing to a function in protocol
0037  *  handler called by ST when the pending registrations are complete.
0038  *  The registrations are marked pending, in situations when fw
0039  *  download is in progress.
0040  * @write: pointer to function in ST provided to protocol drivers from ST,
0041  *  to be made use when protocol drivers have data to send to TTY.
0042  * @priv_data: privdate data holder for the protocol drivers, sent
0043  *  from the protocol drivers during registration, and sent back on
0044  *  reg_complete_cb and recv.
0045  * @chnl_id: channel id the protocol driver is interested in, the channel
0046  *  id is nothing but the 1st byte of the packet in UART frame.
0047  * @max_frame_size: size of the largest frame the protocol can receive.
0048  * @hdr_len: length of the header structure of the protocol.
0049  * @offset_len_in_hdr: this provides the offset of the length field in the
0050  *  header structure of the protocol header, to assist ST to know
0051  *  how much to receive, if the data is split across UART frames.
0052  * @len_size: whether the length field inside the header is 2 bytes
0053  *  or 1 byte.
0054  * @reserve: the number of bytes ST needs to reserve in the skb being
0055  *  prepared for the protocol driver.
0056  */
0057 struct st_proto_s {
0058     enum proto_type type;
0059     long (*recv) (void *, struct sk_buff *);
0060     unsigned char (*match_packet) (const unsigned char *data);
0061     void (*reg_complete_cb) (void *, int data);
0062     long (*write) (struct sk_buff *skb);
0063     void *priv_data;
0064
0065     unsigned char chnl_id;
0066     unsigned short max_frame_size;
0067     unsigned char hdr_len;
0068     unsigned char offset_len_in_hdr;
0069     unsigned char len_size;
0070     unsigned char reserve;
0071 };
0072
0073 extern long st_register(struct st_proto_s *);
0074 extern long st_unregister(struct st_proto_s *);
0075
0076
0077 /*
0078  * header information used by st_core.c
0079  */
0080
0081 /* states of protocol list */
0082 #define ST_NOTEMPTY 1
0083 #define ST_EMPTY    0
0084
0085 /*
0086  * possible st_states
0087  */
0088 #define ST_INITIALIZING     1
0089 #define ST_REG_IN_PROGRESS  2
0090 #define ST_REG_PENDING      3
0091 #define ST_WAITING_FOR_RESP 4
0092
0093 /**
0094  * struct st_data_s - ST core internal structure
0095  * @st_state: different states of ST like initializing, registration
0096  *  in progress, this is mainly used to return relevant err codes
0097  *  when protocol drivers are registering. It is also used to track
0098  *  the recv function, as in during fw download only HCI events
0099  *  can occur , where as during other times other events CH8, CH9
0100  *  can occur.
0101  * @tty: tty provided by the TTY core for line disciplines.
0102  * @tx_skb: If for some reason the tty's write returns lesser bytes written
0103  *  then to maintain the rest of data to be written on next instance.
0104  *  This needs to be protected, hence the lock inside wakeup func.
0105  * @tx_state: if the data is being written onto the TTY and protocol driver
0106  *  wants to send more, queue up data and mark that there is
0107  *  more data to send.
0108  * @list: the list of protocols registered, only MAX can exist, one protocol
0109  *  can register only once.
0110  * @rx_state: states to be maintained inside st's tty receive
0111  * @rx_count: count to be maintained inside st's tty receieve
0112  * @rx_skb: the skb where all data for a protocol gets accumulated,
0113  *  since tty might not call receive when a complete event packet
0114  *  is received, the states, count and the skb needs to be maintained.
0115  * @rx_chnl: the channel ID for which the data is getting accumalated for.
0116  * @txq: the list of skbs which needs to be sent onto the TTY.
0117  * @tx_waitq: if the chip is not in AWAKE state, the skbs needs to be queued
0118  *  up in here, PM(WAKEUP_IND) data needs to be sent and then the skbs
0119  *  from waitq can be moved onto the txq.
0120  *  Needs locking too.
0121  * @lock: the lock to protect skbs, queues, and ST states.
0122  * @protos_registered: count of the protocols registered, also when 0 the
0123  *  chip enable gpio can be toggled, and when it changes to 1 the fw
0124  *  needs to be downloaded to initialize chip side ST.
0125  * @ll_state: the various PM states the chip can be, the states are notified
0126  *  to us, when the chip sends relevant PM packets(SLEEP_IND, WAKE_IND).
0127  * @kim_data: reference to the parent encapsulating structure.
0128  *
0129  */
0130 struct st_data_s {
0131     unsigned long st_state;
0132     struct sk_buff *tx_skb;
0133 #define ST_TX_SENDING   1
0134 #define ST_TX_WAKEUP    2
0135     unsigned long tx_state;
0136     struct st_proto_s *list[ST_MAX_CHANNELS];
0137     bool is_registered[ST_MAX_CHANNELS];
0138     unsigned long rx_state;
0139     unsigned long rx_count;
0140     struct sk_buff *rx_skb;
0141     unsigned char rx_chnl;
0142     struct sk_buff_head txq, tx_waitq;
0143     spinlock_t lock;
0144     unsigned char   protos_registered;
0145     unsigned long ll_state;
0146     void *kim_data;
0147     struct tty_struct *tty;
0148     struct work_struct work_write_wakeup;
0149 };
0150
0151 /*
0152  * wrapper around tty->ops->write_room to check
0153  * availability during firmware download
0154  */
0155 int st_get_uart_wr_room(struct st_data_s *st_gdata);
0156 /**
0157  * st_int_write -
0158  * point this to tty->driver->write or tty->ops->write
0159  * depending upon the kernel version
0160  */
0161 int st_int_write(struct st_data_s*, const unsigned char*, int);
0162
0163 /**
0164  * st_write -
0165  * internal write function, passed onto protocol drivers
0166  * via the write function ptr of protocol struct
0167  */
0168 long st_write(struct sk_buff *);
0169
0170 /* function to be called from ST-LL */
0171 void st_ll_send_frame(enum proto_type, struct sk_buff *);
0172
0173 /* internal wake up function */
0174 void st_tx_wakeup(struct st_data_s *st_data);
0175
0176 /* init, exit entry funcs called from KIM */
0177 int st_core_init(struct st_data_s **);
0178 void st_core_exit(struct st_data_s *);
0179
0180 /* ask for reference from KIM */
0181 void st_kim_ref(struct st_data_s **, int);
0182
0183 #define GPS_STUB_TEST
0184 #ifdef GPS_STUB_TEST
0185 int gps_chrdrv_stub_write(const unsigned char*, int);
0186 void gps_chrdrv_stub_init(void);
0187 #endif
0188
0189 /*
0190  * header information used by st_kim.c
0191  */
0192
0193 /* time in msec to wait for
0194  * line discipline to be installed
0195  */
0196 #define LDISC_TIME  1000
0197 #define CMD_RESP_TIME   800
0198 #define CMD_WR_TIME 5000
0199 #define MAKEWORD(a, b)  ((unsigned short)(((unsigned char)(a)) \
0200     | ((unsigned short)((unsigned char)(b))) << 8))
0201
0202 #define GPIO_HIGH 1
0203 #define GPIO_LOW  0
0204
0205 /* the Power-On-Reset logic, requires to attempt
0206  * to download firmware onto chip more than once
0207  * since the self-test for chip takes a while
0208  */
0209 #define POR_RETRY_COUNT 5
0210
0211 /**
0212  * struct chip_version - save the chip version
0213  */
0214 struct chip_version {
0215     unsigned short full;
0216     unsigned short chip;
0217     unsigned short min_ver;
0218     unsigned short maj_ver;
0219 };
0220
0221 #define UART_DEV_NAME_LEN 32
0222 /**
0223  * struct kim_data_s - the KIM internal data, embedded as the
0224  *  platform's drv data. One for each ST device in the system.
0225  * @uim_pid: KIM needs to communicate with UIM to request to install
0226  *  the ldisc by opening UART when protocol drivers register.
0227  * @kim_pdev: the platform device added in one of the board-XX.c file
0228  *  in arch/XX/ directory, 1 for each ST device.
0229  * @kim_rcvd: completion handler to notify when data was received,
0230  *  mainly used during fw download, which involves multiple send/wait
0231  *  for each of the HCI-VS commands.
0232  * @ldisc_installed: completion handler to notify that the UIM accepted
0233  *  the request to install ldisc, notify from tty_open which suggests
0234  *  the ldisc was properly installed.
0235  * @resp_buffer: data buffer for the .bts fw file name.
0236  * @fw_entry: firmware class struct to request/release the fw.
0237  * @rx_state: the rx state for kim's receive func during fw download.
0238  * @rx_count: the rx count for the kim's receive func during fw download.
0239  * @rx_skb: all of fw data might not come at once, and hence data storage for
0240  *  whole of the fw response, only HCI_EVENTs and hence diff from ST's
0241  *  response.
0242  * @core_data: ST core's data, which mainly is the tty's disc_data
0243  * @version: chip version available via a sysfs entry.
0244  *
0245  */
0246 struct kim_data_s {
0247     long uim_pid;
0248     struct platform_device *kim_pdev;
0249     struct completion kim_rcvd, ldisc_installed;
0250     char resp_buffer[30];
0251     const struct firmware *fw_entry;
0252     unsigned nshutdown;
0253     unsigned long rx_state;
0254     unsigned long rx_count;
0255     struct sk_buff *rx_skb;
0256     struct st_data_s *core_data;
0257     struct chip_version version;
0258     unsigned char ldisc_install;
0259     unsigned char dev_name[UART_DEV_NAME_LEN + 1];
0260     unsigned flow_cntrl;
0261     unsigned baud_rate;
0262 };
0263
0264 /**
0265  * functions called when 1 of the protocol drivers gets
0266  * registered, these need to communicate with UIM to request
0267  * ldisc installed, read chip_version, download relevant fw
0268  */
0269 long st_kim_start(void *);
0270 long st_kim_stop(void *);
0271
0272 void st_kim_complete(void *);
0273 void kim_st_list_protocols(struct st_data_s *, void *);
0274 void st_kim_recv(void *, const unsigned char *, long);
0275
0276
0277 /*
0278  * BTS headers
0279  */
0280 #define ACTION_SEND_COMMAND     1
0281 #define ACTION_WAIT_EVENT       2
0282 #define ACTION_SERIAL           3
0283 #define ACTION_DELAY            4
0284 #define ACTION_RUN_SCRIPT       5
0285 #define ACTION_REMARKS          6
0286
0287 /**
0288  * struct bts_header - the fw file is NOT binary which can
0289  *  be sent onto TTY as is. The .bts is more a script
0290  *  file which has different types of actions.
0291  *  Each such action needs to be parsed by the KIM and
0292  *  relevant procedure to be called.
0293  */
0294 struct bts_header {
0295     u32 magic;
0296     u32 version;
0297     u8 future[24];
0298     u8 actions[];
0299 } __attribute__ ((packed));
0300
0301 /**
0302  * struct bts_action - Each .bts action has its own type of
0303  *  data.
0304  */
0305 struct bts_action {
0306     u16 type;
0307     u16 size;
0308     u8 data[];
0309 } __attribute__ ((packed));
0310
0311 struct bts_action_send {
0312     u8 data[0];
0313 } __attribute__ ((packed));
0314
0315 struct bts_action_wait {
0316     u32 msec;
0317     u32 size;
0318     u8 data[];
0319 } __attribute__ ((packed));
0320
0321 struct bts_action_delay {
0322     u32 msec;
0323 } __attribute__ ((packed));
0324
0325 struct bts_action_serial {
0326     u32 baud;
0327     u32 flow_control;
0328 } __attribute__ ((packed));
0329
0330 /**
0331  * struct hci_command - the HCI-VS for intrepreting
0332  *  the change baud rate of host-side UART, which
0333  *  needs to be ignored, since UIM would do that
0334  *  when it receives request from KIM for ldisc installation.
0335  */
0336 struct hci_command {
0337     u8 prefix;
0338     u16 opcode;
0339     u8 plen;
0340     u32 speed;
0341 } __attribute__ ((packed));
0342
0343 /*
0344  * header information used by st_ll.c
0345  */
0346
0347 /* ST LL receiver states */
0348 #define ST_W4_PACKET_TYPE       0
0349 #define ST_W4_HEADER        1
0350 #define ST_W4_DATA      2
0351
0352 /* ST LL state machines */
0353 #define ST_LL_ASLEEP               0
0354 #define ST_LL_ASLEEP_TO_AWAKE      1
0355 #define ST_LL_AWAKE                2
0356 #define ST_LL_AWAKE_TO_ASLEEP      3
0357 #define ST_LL_INVALID          4
0358
0359 /* different PM notifications coming from chip */
0360 #define LL_SLEEP_IND    0x30
0361 #define LL_SLEEP_ACK    0x31
0362 #define LL_WAKE_UP_IND  0x32
0363 #define LL_WAKE_UP_ACK  0x33
0364
0365 /* initialize and de-init ST LL */
0366 long st_ll_init(struct st_data_s *);
0367 long st_ll_deinit(struct st_data_s *);
0368
0369 /**
0370  * enable/disable ST LL along with KIM start/stop
0371  * called by ST Core
0372  */
0373 void st_ll_enable(struct st_data_s *);
0374 void st_ll_disable(struct st_data_s *);
0375
0376 /**
0377  * various funcs used by ST core to set/get the various PM states
0378  * of the chip.
0379  */
0380 unsigned long st_ll_getstate(struct st_data_s *);
0381 unsigned long st_ll_sleep_state(struct st_data_s *, unsigned char);
0382 void st_ll_wakeup(struct st_data_s *);
0383
0384 /*
0385  * header information used by st_core.c for FM and GPS
0386  * packet parsing, the bluetooth headers are already available
0387  * at net/bluetooth/
0388  */
0389
0390 struct fm_event_hdr {
0391     u8 plen;
0392 } __attribute__ ((packed));
0393
0394 #define FM_MAX_FRAME_SIZE 0xFF  /* TODO: */
0395 #define FM_EVENT_HDR_SIZE 1 /* size of fm_event_hdr */
0396 #define ST_FM_CH8_PKT 0x8
0397
0398 /* gps stuff */
0399 struct gps_event_hdr {
0400     u8 opcode;
0401     u16 plen;
0402 } __attribute__ ((packed));
0403
0404 /**
0405  * struct ti_st_plat_data - platform data shared between ST driver and
0406  *  platform specific board file which adds the ST device.
0407  * @nshutdown_gpio: Host's GPIO line to which chip's BT_EN is connected.
0408  * @dev_name: The UART/TTY name to which chip is interfaced. (eg: /dev/ttyS1)
0409  * @flow_cntrl: Should always be 1, since UART's CTS/RTS is used for PM
0410  *  purposes.
0411  * @baud_rate: The baud rate supported by the Host UART controller, this will
0412  *  be shared across with the chip via a HCI VS command from User-Space Init
0413  *  Mgr application.
0414  * @suspend:
0415  * @resume: legacy PM routines hooked to platform specific board file, so as
0416  *  to take chip-host interface specific action.
0417  * @chip_enable:
0418  * @chip_disable: Platform/Interface specific mux mode setting, GPIO
0419  *  configuring, Host side PM disabling etc.. can be done here.
0420  * @chip_asleep:
0421  * @chip_awake: Chip specific deep sleep states is communicated to Host
0422  *  specific board-xx.c to take actions such as cut UART clocks when chip
0423  *  asleep or run host faster when chip awake etc..
0424  *
0425  */
0426 struct ti_st_plat_data {
0427     u32 nshutdown_gpio;
0428     unsigned char dev_name[UART_DEV_NAME_LEN]; /* uart name */
0429     u32 flow_cntrl; /* flow control flag */
0430     u32 baud_rate;
0431     int (*suspend)(struct platform_device *, pm_message_t);
0432     int (*resume)(struct platform_device *);
0433     int (*chip_enable) (struct kim_data_s *);
0434     int (*chip_disable) (struct kim_data_s *);
0435     int (*chip_asleep) (struct kim_data_s *);
0436     int (*chip_awake) (struct kim_data_s *);
0437 };
0438
0439 #endif /* TI_WILINK_ST_H */