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
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
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
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__ */