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/* SPDX-License-Identifier: GPL-2.0-only */
/*
 *  FM Driver for Connectivity chip of Texas Instruments.
 *
 *  Common header for all FM driver sub-modules.
 *
 *  Copyright (C) 2011 Texas Instruments
 */

#ifndef _FM_DRV_H
#define _FM_DRV_H

#include <linux/skbuff.h>
#include <linux/interrupt.h>
#include <sound/core.h>
#include <sound/initval.h>
#include <linux/timer.h>
#include <media/v4l2-ioctl.h>
#include <media/v4l2-common.h>
#include <media/v4l2-device.h>
#include <media/v4l2-ctrls.h>

#define FM_DRV_VERSION            "0.1.1"
#define FM_DRV_NAME               "ti_fmdrv"
#define FM_DRV_CARD_SHORT_NAME    "TI FM Radio"
#define FM_DRV_CARD_LONG_NAME     "Texas Instruments FM Radio"

/* Flag info */
#define FM_INTTASK_RUNNING            0
#define FM_INTTASK_SCHEDULE_PENDING   1
#define FM_FW_DW_INPROGRESS     2
#define FM_CORE_READY                 3
#define FM_CORE_TRANSPORT_READY       4
#define FM_AF_SWITCH_INPROGRESS	      5
#define FM_CORE_TX_XMITING	      6

#define FM_TUNE_COMPLETE	      0x1
#define FM_BAND_LIMIT		      0x2

#define FM_DRV_TX_TIMEOUT      (5*HZ)	/* 5 seconds */
#define FM_DRV_RX_SEEK_TIMEOUT (20*HZ)	/* 20 seconds */

#define fmerr(format, ...) \
	printk(KERN_ERR "fmdrv: " format, ## __VA_ARGS__)
#define fmwarn(format, ...) \
	printk(KERN_WARNING "fmdrv: " format, ##__VA_ARGS__)
#ifdef DEBUG
#define fmdbg(format, ...) \
	printk(KERN_DEBUG "fmdrv: " format, ## __VA_ARGS__)
#else /* DEBUG */
#define fmdbg(format, ...) do {} while(0)
#endif
enum {
	FM_MODE_OFF,
	FM_MODE_TX,
	FM_MODE_RX,
	FM_MODE_ENTRY_MAX
};

#define FM_RX_RDS_INFO_FIELD_MAX	8	/* 4 Group * 2 Bytes */

/* RX RDS data format */
struct fm_rdsdata_format {
	union {
		struct {
			u8 buff[FM_RX_RDS_INFO_FIELD_MAX];
		} groupdatabuff;
		struct {
			u16 pidata;
			u8 blk_b[2];
			u8 blk_c[2];
			u8 blk_d[2];
		} groupgeneral;
		struct {
			u16 pidata;
			u8 blk_b[2];
			u8 af[2];
			u8 ps[2];
		} group0A;
		struct {
			u16 pi[2];
			u8 blk_b[2];
			u8 ps[2];
		} group0B;
	} data;
};

/* FM region (Europe/US, Japan) info */
struct region_info {
	u32 chanl_space;
	u32 bot_freq;
	u32 top_freq;
	u8 fm_band;
};
struct fmdev;
typedef void (*int_handler_prototype) (struct fmdev *);

/* FM Interrupt processing related info */
struct fm_irq {
	u8 stage;
	u16 flag;	/* FM interrupt flag */
	u16 mask;	/* FM interrupt mask */
	/* Interrupt process timeout handler */
	struct timer_list timer;
	u8 retry;
	int_handler_prototype *handlers;
};

/* RDS info */
struct fm_rds {
	u8 flag;	/* RX RDS on/off status */
	u8 last_blk_idx;	/* Last received RDS block */

	/* RDS buffer */
	wait_queue_head_t read_queue;
	u32 buf_size;	/* Size is always multiple of 3 */
	u32 wr_idx;
	u32 rd_idx;
	u8 *buff;
};

#define FM_RDS_MAX_AF_LIST		25

/*
 * Current RX channel Alternate Frequency cache.
 * This info is used to switch to other freq (AF)
 * when current channel signal strength is below RSSI threshold.
 */
struct tuned_station_info {
	u16 picode;
	u32 af_cache[FM_RDS_MAX_AF_LIST];
	u8 afcache_size;
	u8 af_list_max;
};

/* FM RX mode info */
struct fm_rx {
	struct region_info region;	/* Current selected band */
	u32 freq;	/* Current RX frquency */
	u8 mute_mode;	/* Current mute mode */
	u8 deemphasis_mode; /* Current deemphasis mode */
	/* RF dependent soft mute mode */
	u8 rf_depend_mute;
	u16 volume;	/* Current volume level */
	u16 rssi_threshold;	/* Current RSSI threshold level */
	/* Holds the index of the current AF jump */
	u8 afjump_idx;
	/* Will hold the frequency before the jump */
	u32 freq_before_jump;
	u8 rds_mode;	/* RDS operation mode (RDS/RDBS) */
	u8 af_mode;	/* Alternate frequency on/off */
	struct tuned_station_info stat_info;
	struct fm_rds rds;
};

#define FMTX_RDS_TXT_STR_SIZE	25
/*
 * FM TX RDS data
 *
 * @ text_type: is the text following PS or RT
 * @ text: radio text string which could either be PS or RT
 * @ af_freq: alternate frequency for Tx
 * TODO: to be declared in application
 */
struct tx_rds {
	u8 text_type;
	u8 text[FMTX_RDS_TXT_STR_SIZE];
	u8 flag;
	u32 af_freq;
};
/*
 * FM TX global data
 *
 * @ pwr_lvl: Power Level of the Transmission from mixer control
 * @ xmit_state: Transmission state = Updated locally upon Start/Stop
 * @ audio_io: i2S/Analog
 * @ tx_frq: Transmission frequency
 */
struct fmtx_data {
	u8 pwr_lvl;
	u8 xmit_state;
	u8 audio_io;
	u8 region;
	u16 aud_mode;
	u32 preemph;
	u32 tx_frq;
	struct tx_rds rds;
};

/* FM driver operation structure */
struct fmdev {
	struct video_device *radio_dev;	/* V4L2 video device pointer */
	struct v4l2_device v4l2_dev;	/* V4L2 top level struct */
	struct snd_card *card;	/* Card which holds FM mixer controls */
	u16 asci_id;
	spinlock_t rds_buff_lock; /* To protect access to RDS buffer */
	spinlock_t resp_skb_lock; /* To protect access to received SKB */

	long flag;		/*  FM driver state machine info */
	int streg_cbdata; /* status of ST registration */

	struct sk_buff_head rx_q;	/* RX queue */
	struct tasklet_struct rx_task;	/* RX Tasklet */

	struct sk_buff_head tx_q;	/* TX queue */
	struct tasklet_struct tx_task;	/* TX Tasklet */
	unsigned long last_tx_jiffies;	/* Timestamp of last pkt sent */
	atomic_t tx_cnt;	/* Number of packets can send at a time */

	struct sk_buff *resp_skb;	/* Response from the chip */
	/* Main task completion handler */
	struct completion maintask_comp;
	/* Opcode of last command sent to the chip */
	u8 pre_op;
	/* Handler used for wakeup when response packet is received */
	struct completion *resp_comp;
	struct fm_irq irq_info;
	u8 curr_fmmode; /* Current FM chip mode (TX, RX, OFF) */
	struct fm_rx rx;	/* FM receiver info */
	struct fmtx_data tx_data;

	/* V4L2 ctrl framework handler*/
	struct v4l2_ctrl_handler ctrl_handler;

	/* For core assisted locking */
	struct mutex mutex;
};
#endif