1  /* SPDX-License-Identifier: GPL-2.0-or-later */
2  /*
3      tuner-i2c.h - i2c interface for different tuners
4  
5      Copyright (C) 2007 Michael Krufky (mkrufky@linuxtv.org)
6  
7  */
8  
9  #ifndef __TUNER_I2C_H__
10  #define __TUNER_I2C_H__
11  
12  #include <linux/i2c.h>
13  #include <linux/slab.h>
14  
15  struct tuner_i2c_props {
16  	u8 addr;
17  	struct i2c_adapter *adap;
18  
19  	/* used for tuner instance management */
20  	int count;
21  	char *name;
22  };
23  
tuner_i2c_xfer_send(struct tuner_i2c_props * props,unsigned char * buf,int len)24  static inline int tuner_i2c_xfer_send(struct tuner_i2c_props *props,
25  				      unsigned char *buf, int len)
26  {
27  	struct i2c_msg msg = { .addr = props->addr, .flags = 0,
28  			       .buf = buf, .len = len };
29  	int ret = i2c_transfer(props->adap, &msg, 1);
30  
31  	return (ret == 1) ? len : ret;
32  }
33  
tuner_i2c_xfer_recv(struct tuner_i2c_props * props,unsigned char * buf,int len)34  static inline int tuner_i2c_xfer_recv(struct tuner_i2c_props *props,
35  				      unsigned char *buf, int len)
36  {
37  	struct i2c_msg msg = { .addr = props->addr, .flags = I2C_M_RD,
38  			       .buf = buf, .len = len };
39  	int ret = i2c_transfer(props->adap, &msg, 1);
40  
41  	return (ret == 1) ? len : ret;
42  }
43  
tuner_i2c_xfer_send_recv(struct tuner_i2c_props * props,unsigned char * obuf,int olen,unsigned char * ibuf,int ilen)44  static inline int tuner_i2c_xfer_send_recv(struct tuner_i2c_props *props,
45  					   unsigned char *obuf, int olen,
46  					   unsigned char *ibuf, int ilen)
47  {
48  	struct i2c_msg msg[2] = { { .addr = props->addr, .flags = 0,
49  				    .buf = obuf, .len = olen },
50  				  { .addr = props->addr, .flags = I2C_M_RD,
51  				    .buf = ibuf, .len = ilen } };
52  	int ret = i2c_transfer(props->adap, msg, 2);
53  
54  	return (ret == 2) ? ilen : ret;
55  }
56  
57  /* Callers must declare as a global for the module:
58   *
59   * static LIST_HEAD(hybrid_tuner_instance_list);
60   *
61   * hybrid_tuner_instance_list should be the third argument
62   * passed into hybrid_tuner_request_state().
63   *
64   * state structure must contain the following:
65   *
66   *	struct list_head	hybrid_tuner_instance_list;
67   *	struct tuner_i2c_props	i2c_props;
68   *
69   * hybrid_tuner_instance_list (both within state structure and globally)
70   * is only required if the driver is using hybrid_tuner_request_state
71   * and hybrid_tuner_release_state to manage state sharing between
72   * multiple instances of hybrid tuners.
73   */
74  
75  #define tuner_printk(kernlvl, i2cprops, fmt, arg...) do {		\
76  	printk(kernlvl "%s %d-%04x: " fmt, i2cprops.name,		\
77  			i2cprops.adap ?					\
78  				i2c_adapter_id(i2cprops.adap) : -1,	\
79  			i2cprops.addr, ##arg);				\
80  	 } while (0)
81  
82  /* TO DO: convert all callers of these macros to pass in
83   * struct tuner_i2c_props, then remove the macro wrappers */
84  
85  #define __tuner_warn(i2cprops, fmt, arg...) do {			\
86  	tuner_printk(KERN_WARNING, i2cprops, fmt, ##arg);		\
87  	} while (0)
88  
89  #define __tuner_info(i2cprops, fmt, arg...) do {			\
90  	tuner_printk(KERN_INFO, i2cprops, fmt, ##arg);			\
91  	} while (0)
92  
93  #define __tuner_err(i2cprops, fmt, arg...) do {				\
94  	tuner_printk(KERN_ERR, i2cprops, fmt, ##arg);			\
95  	} while (0)
96  
97  #define __tuner_dbg(i2cprops, fmt, arg...) do {				\
98  	if ((debug))							\
99  		tuner_printk(KERN_DEBUG, i2cprops, fmt, ##arg);		\
100  	} while (0)
101  
102  #define tuner_warn(fmt, arg...) __tuner_warn(priv->i2c_props, fmt, ##arg)
103  #define tuner_info(fmt, arg...) __tuner_info(priv->i2c_props, fmt, ##arg)
104  #define tuner_err(fmt, arg...) __tuner_err(priv->i2c_props, fmt, ##arg)
105  #define tuner_dbg(fmt, arg...) __tuner_dbg(priv->i2c_props, fmt, ##arg)
106  
107  /****************************************************************************/
108  
109  /* The return value of hybrid_tuner_request_state indicates the number of
110   * instances using this tuner object.
111   *
112   * 0 - no instances, indicates an error - kzalloc must have failed
113   *
114   * 1 - one instance, indicates that the tuner object was created successfully
115   *
116   * 2 (or more) instances, indicates that an existing tuner object was found
117   */
118  
119  #define hybrid_tuner_request_state(type, state, list, i2cadap, i2caddr, devname)\
120  ({									\
121  	int __ret = 0;							\
122  	list_for_each_entry(state, &list, hybrid_tuner_instance_list) {	\
123  		if (((i2cadap) && (state->i2c_props.adap)) &&		\
124  		    ((i2c_adapter_id(state->i2c_props.adap) ==		\
125  		      i2c_adapter_id(i2cadap)) &&			\
126  		     (i2caddr == state->i2c_props.addr))) {		\
127  			__tuner_info(state->i2c_props,			\
128  				     "attaching existing instance\n");	\
129  			state->i2c_props.count++;			\
130  			__ret = state->i2c_props.count;			\
131  			break;						\
132  		}							\
133  	}								\
134  	if (0 == __ret) {						\
135  		state = kzalloc(sizeof(type), GFP_KERNEL);		\
136  		if (NULL == state)					\
137  			goto __fail;					\
138  		state->i2c_props.addr = i2caddr;			\
139  		state->i2c_props.adap = i2cadap;			\
140  		state->i2c_props.name = devname;			\
141  		__tuner_info(state->i2c_props,				\
142  			     "creating new instance\n");		\
143  		list_add_tail(&state->hybrid_tuner_instance_list, &list);\
144  		state->i2c_props.count++;				\
145  		__ret = state->i2c_props.count;				\
146  	}								\
147  __fail:									\
148  	__ret;								\
149  })
150  
151  #define hybrid_tuner_release_state(state)				\
152  ({									\
153  	int __ret;							\
154  	state->i2c_props.count--;					\
155  	__ret = state->i2c_props.count;					\
156  	if (!state->i2c_props.count) {					\
157  		__tuner_info(state->i2c_props, "destroying instance\n");\
158  		list_del(&state->hybrid_tuner_instance_list);		\
159  		kfree(state);						\
160  	}								\
161  	__ret;								\
162  })
163  
164  #define hybrid_tuner_report_instance_count(state)			\
165  ({									\
166  	int __ret = 0;							\
167  	if (state)							\
168  		__ret = state->i2c_props.count;				\
169  	__ret;								\
170  })
171  
172  #endif /* __TUNER_I2C_H__ */
173