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5 x( _0 n; U" Q( N6 K4 u( U$ e3 O3 Otypedef signed int rt_int32_t;- I; }4 q; I- O# T% m- T
typedef unsigned int rt_uint32_t;
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3 c- J- K+ b+ v+ o) L, v1 b8 C" L6 hstruct rt_i2c_bit_ops
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. p8 Z" ]: V' C/ t! w t, G void *data; /* private data for lowlevel routines */
0 a/ \9 w! N: ~. n void (*set_sda)(void *data, rt_int32_t state);
7 N) U. {; o, d) }1 s void (*set_scl)(void *data, rt_int32_t state);0 y5 D: W$ O7 F6 l; x9 [& t% q9 B
rt_int32_t (*get_sda)(void *data);
C: K& f3 m( w4 w, d rt_int32_t (*get_scl)(void *data);
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0 ~$ Y3 Y- ?7 @/ I void (*udelay)(rt_uint32_t us);
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rt_uint32_t delay_us; /* scl and sda line delay */6 O% N5 P4 I9 } w( F: J" V
rt_uint32_t timeout; /* in tick */
+ h$ X/ T" y+ X ~};
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//结构体功能函数的使用 它的精妙之处在这里,用宏把结构体函数使用起来
: W* D" l3 X3 j! Y#define SET_SDA(ops, val) ops->set_sda(ops->data, val)
E6 g `# ?, n2 c1 a+ c#define SET_SCL(ops, val) ops->set_scl(ops->data, val)
# o/ n: ^6 f$ k* _9 t#define GET_SDA(ops) ops->get_sda(ops->data) z4 r. x# P$ u5 g% ]# I
#define GET_SCL(ops) ops->get_scl(ops->data)% o$ W9 X p- u2 A% k
//结构体功能函数的使用2 `/ d! C* G% |: A9 a
#define SDA_L(ops) SET_SDA(ops, 0)
f! S- I7 |. x% C#define SDA_H(ops) SET_SDA(ops, 1)
1 f: P5 P- F6 I#define SCL_L(ops) SET_SCL(ops, 0)
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//提供对外使用
7 u5 I+ G8 o9 p# g7 Q( [* @inline void i2c_delay(struct rt_i2c_bit_ops *ops)- x2 e/ K- ^" p0 K( t
{
" D0 D: @8 f6 I ops->udelay((ops->delay_us + 1) >> 1);
, W! S" T( W- l: i5 L7 F& s' K, e3 o}
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inline void i2c_delay2(struct rt_i2c_bit_ops *ops)( L; y/ [, A2 J, `
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ops->udelay(ops->delay_us);
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//以下为rt_i2c_bit_ops指针函数
) c1 @& b, O8 w. T2 uvoid i2c_set_sda(void *data, rt_int32_t state)
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if(state)$ Z4 Y; y5 P' L$ B$ S* J
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printf("sda->H\r\n");
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{
$ b" d+ p" \0 ] u& Z! ` printf("sda->L\r\n");
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}
: H4 w. }& o+ B8 {8 K( ?8 \9 Xvoid i2c_set_scl(void *data, rt_int32_t state)
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) u( r# U( ]* g( S3 N0 z; C if(state)4 v$ p; L$ S0 ?' e
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printf("scl->H\r\n");
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printf("scl->L\r\n");
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rt_int32_t i2c_get_sda(void *data)- M! H! v. F) ?2 u
{
, }2 b* ?( w& Y printf("sda return 1\r\n");
9 t* W* _ Q# O- ~' D return 1;
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rt_int32_t i2c_get_scl(void *data)6 U6 n/ ~% I k3 w
{
1 w5 L. X& h# }1 p3 {/ p, ` printf("scl return 1\r\n");
9 W- _; `! u/ d& g/ K, o return 1;4 x8 c) b2 e, o; {- l+ C X+ w% H
}
: v9 c8 n9 b) A; Qvoid udelay(rt_uint32_t us)
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printf("udelay %d us\r\n",us);, b ~9 Q2 y, _% v) A5 z4 p
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//以上为rt_i2c_bit_ops指针函数" y" y/ N& W) E5 z- ^
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//模拟i2c的其他信号可以类似i2c_restart一样调用# R. X8 R/ H. X2 f- w& q f* X
static void i2c_restart(struct rt_i2c_bit_ops *ops)
& x( S$ H* I7 z7 W{
3 W( r* M* d. m D3 M1 v l/ l SDA_H(ops);) o+ u; o* H8 J. @& S9 P% L
i2c_delay(ops);% D4 M2 w. N# p1 m* m2 b! ^. R
SDA_L(ops);
8 B- Y7 e/ O( g$ s6 u' k4 {8 O. j i2c_delay(ops);( J% S$ W$ i& x; H5 ^
SCL_L(ops);& q1 \$ M a6 p, z7 z
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int main(int argc, char* argv[])! ? ^' G. ?/ e
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rt_i2c_bit_ops i2c_ops;6 ?- k6 }8 p3 P$ ^+ G( _ @5 M: H
i2c_ops.data = (void *)0x88; p! Y1 h+ L8 x3 i! H
i2c_ops.delay_us = 5;
/ w4 B/ N7 i) X5 }# ? i2c_ops.udelay = udelay;
! [5 G9 _# A8 ]( i3 ?1 R+ v i2c_ops.get_scl = i2c_get_scl;
' Q3 E+ I; j3 J* L5 N i2c_ops.get_sda = i2c_get_sda;, P; A# R: Q& ]! W
i2c_ops.set_scl = i2c_set_scl;1 H* R) e2 G! ^' {* P! o. J
i2c_ops.set_sda = i2c_set_sda;; I+ d8 }8 M$ U' G1 E# M5 S6 V+ _
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printf("==========TEST===========!\n");4 z" _, Q4 L/ G/ b& I% V4 h
! G* o! \" J6 ^5 N( P$ v 以上设置完专门的i2c接口后,类似与i2c_restart这样的i2c发送和接收的业务逻辑函数基本上不用修改了,直接按不同的i2c接口传参即可完成i2c的功能。
1 o6 {+ a7 l# J i2c_restart(&i2c_ops);7 g6 ~9 t, u8 c
return 0;
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