3 files changed, 105 insertions, 121 deletions

diff --git a/firmware/drivers/generic_i2c.c b/firmware/drivers/generic_i2c.c
index 87e9091a3d..effb5372b4 100644
--- a/firmware/drivers/generic_i2c.c
+++ b/firmware/drivers/generic_i2c.c
@@ -32,55 +32,51 @@ static const struct i2c_interface *i2c_if[MAX_I2C_INTERFACES];
 
 static void i2c_start(const struct i2c_interface *iface)
 {
-    iface->sda_output();
-
-    iface->sda_hi();
-    iface->scl_hi();
-    iface->delay_su_sta();
-    iface->sda_lo();
-    iface->delay_hd_sta();
-    iface->scl_lo();
-    iface->delay_hd_dat();
+    iface->sda_dir(true);
+
+    iface->sda_out(1);
+    iface->scl_out(1);
+    iface->delay(iface->delay_su_sta);
+    iface->sda_out(0);
+    iface->delay(iface->delay_hd_sta);
+    iface->scl_out(0);
+    iface->delay(iface->delay_hd_dat);
 }
 
 static void i2c_stop(const struct i2c_interface *iface)
 {
-    iface->sda_output();
+    iface->sda_dir(true);
 
-    iface->sda_lo();
-    iface->delay_su_dat();
-    iface->scl_hi();
-    iface->delay_su_sto();
-    iface->sda_hi();
+    iface->sda_out(0);
+    iface->delay(iface->delay_su_dat);
+    iface->scl_out(1);
+    iface->delay(iface->delay_su_sto);
+    iface->sda_out(1);
 }
 
 static void i2c_ack(const struct i2c_interface *iface, bool ack)
 {
-    iface->sda_output();
-    if ( ack )
-        iface->sda_lo();
-    else
-        iface->sda_hi();
-
-    iface->delay_su_dat();
-    iface->scl_hi();
-    iface->delay_thigh();
-    iface->scl_lo();
-    iface->delay_hd_dat();
+    iface->sda_dir(true);
+    iface->sda_out(!ack);
+    iface->delay(iface->delay_su_dat);
+    iface->scl_out(1);
+    iface->delay(iface->delay_thigh);
+    iface->scl_out(0);
+    iface->delay(iface->delay_hd_dat);
 }
 
 static int i2c_getack(const struct i2c_interface *iface)
 {
     int ret = 1;
 
-    iface->sda_input();
-    iface->delay_su_dat();
-    iface->scl_hi();
-    iface->delay_thigh();
-    if (iface->sda())
+    iface->sda_dir(false);
+    iface->delay(iface->delay_su_dat);
+    iface->scl_out(1);
+    iface->delay(iface->delay_thigh);
+    if (iface->sda_in())
         ret = 0; /* ack failed */
-    iface->scl_lo();
-    iface->delay_hd_dat();
+    iface->scl_out(0);
+    iface->delay(iface->delay_hd_dat);
     return ret;
 }
 
@@ -89,17 +85,17 @@ static unsigned char i2c_inb(const struct i2c_interface *iface, bool ack)
     int i;
     unsigned char byte = 0;
 
-    iface->sda_input();
+    iface->sda_dir(false);
 
     /* clock in each bit, MSB first */
     for ( i=0x80; i; i>>=1 ) {
-        iface->delay_su_dat();
-        iface->scl_hi();
-        iface->delay_thigh();
-        if (iface->sda())
+        iface->delay(iface->delay_su_dat);
+        iface->scl_out(1);
+        iface->delay(iface->delay_thigh);
+        if (iface->sda_in())
             byte |= i;
-        iface->scl_lo();
-        iface->delay_hd_dat();
+        iface->scl_out(0);
+        iface->delay(iface->delay_hd_dat);
     }
 
     i2c_ack(iface, ack);
@@ -111,18 +107,16 @@ static int i2c_outb(const struct i2c_interface *iface, unsigned char byte)
 {
     int i;
 
-    iface->sda_output();
+    iface->sda_dir(true);
 
     /* clock out each bit, MSB first */
     for (i=0x80; i; i>>=1) {
-        if (i & byte)
-            iface->sda_hi();
-        else
-            iface->sda_lo();
-        iface->delay_su_dat();
-        iface->scl_hi();
-        iface->delay_thigh();
-        iface->scl_lo();
+        iface->sda_out(i & byte);
+        iface->delay(iface->delay_su_dat);
+        iface->scl_out(1);
+        iface->delay(iface->delay_thigh);
+        iface->scl_out(0);
+        iface->delay(iface->delay_hd_dat);
    }
 
    return i2c_getack(iface);
@@ -215,7 +209,7 @@ int i2c_add_node(const struct i2c_interface *iface)
     bus_index = i2c_num_ifs++;
     i2c_if[bus_index] = iface;
 
-    iface->scl_output();
+    iface->scl_dir(true);
 
     return bus_index;
 }
diff --git a/firmware/export/generic_i2c.h b/firmware/export/generic_i2c.h
index 6679b78415..f71736acf0 100644
--- a/firmware/export/generic_i2c.h
+++ b/firmware/export/generic_i2c.h
@@ -21,27 +21,26 @@
 #ifndef _GEN_I2C_
 #define _GEN_I2C_
 
+#include <stdbool.h>
+
 struct i2c_interface
 {
-    void (*scl_hi)(void);  /* Drive SCL high, might sleep on clk stretch */
-    void (*scl_lo)(void);  /* Drive SCL low */
-    void (*sda_hi)(void);  /* Drive SDA high */
-    void (*sda_lo)(void);  /* Drive SDA low */
-    void (*sda_input)(void);  /* Set SDA as input */
-    void (*sda_output)(void); /* Set SDA as output */
-    void (*scl_input)(void);  /* Set SCL as input */
-    void (*scl_output)(void); /* Set SCL as output */
-    int (*scl)(void);      /* Read SCL, returns 0 or non-zero */
-    int (*sda)(void);      /* Read SDA, returns 0 or non-zero */
-
+    void (*scl_dir)(bool out);  /* Set SCL as input or output */
+    void (*sda_dir)(bool out);  /* Set SDA as input or output */
+    void (*scl_out)(bool high); /* Drive SCL, might sleep on clk stretch */
+    void (*sda_out)(bool high); /* Drive SDA */
+    bool (*scl_in)(void);       /* Read SCL, returns true if high */
+    bool (*sda_in)(void);       /* Read SDA, returns true if high */
+    void (*delay)(int delay);   /* Delay for the specified amount */
+    
     /* These are the delays specified in the I2C specification, the
        time pairs to the right are the minimum 100kHz and 400kHz specs */
-    void (*delay_hd_sta)(void); /* START SDA hold (tHD:SDA)    4.0us/0.6us */
-    void (*delay_hd_dat)(void); /* SDA hold (tHD:DAT)          5.0us/0us   */
-    void (*delay_su_dat)(void); /* SDA setup (tSU:DAT)         250ns/100ns */
-    void (*delay_su_sto)(void); /* STOP setup (tSU:STO)        4.0us/0.6us */
-    void (*delay_su_sta)(void); /* Rep. START setup (tSU:STA)  4.7us/0.6us */
-    void (*delay_thigh)(void);  /* SCL high period (tHIGH)     4.0us/0.6us */
+    int delay_hd_sta;           /* START SDA hold (tHD:SDA)    4.0us/0.6us */
+    int delay_hd_dat;           /* SDA hold (tHD:DAT)          5.0us/0us   */
+    int delay_su_dat;           /* SDA setup (tSU:DAT)         250ns/100ns */
+    int delay_su_sto;           /* STOP setup (tSU:STO)        4.0us/0.6us */
+    int delay_su_sta;           /* Rep. START setup (tSU:STA)  4.7us/0.6us */
+    int delay_thigh;            /* SCL high period (tHIGH)     4.0us/0.6us */
 };
 
 int i2c_add_node(const struct i2c_interface *iface);
diff --git a/firmware/target/arm/as3525/fmradio-i2c-as3525.c b/firmware/target/arm/as3525/fmradio-i2c-as3525.c
index 33d12f9fa7..9e8dc63144 100644
--- a/firmware/target/arm/as3525/fmradio-i2c-as3525.c
+++ b/firmware/target/arm/as3525/fmradio-i2c-as3525.c
@@ -28,6 +28,7 @@
  */
 
 #include "as3525.h"
+#include "system.h"
 #include "generic_i2c.h"
 #include "fmradio_i2c.h"
 
@@ -77,85 +78,75 @@
 
 static int fm_i2c_bus;
 
-static void fm_scl_hi(void)
+static void fm_scl_dir(bool out)
 {
-    I2C_SCL_GPIO(I2C_SCL_PIN) = 1 << I2C_SCL_PIN;
-}
-
-static void fm_scl_lo(void)
-{
-    I2C_SCL_GPIO(I2C_SCL_PIN) = 0;
-}
-
-static void fm_sda_hi(void)
-{
-    I2C_SDA_GPIO(I2C_SDA_PIN) = 1 << I2C_SDA_PIN;
-}
-
-static void fm_sda_lo(void)
-{
-    I2C_SDA_GPIO(I2C_SDA_PIN) = 0;
+    if (out) {
+        I2C_SCL_GPIO_DIR |= 1 << I2C_SCL_PIN;
+    } else {
+        I2C_SCL_GPIO_DIR &= ~(1 << I2C_SCL_PIN);
+    }
 }
 
-static void fm_sda_input(void)
+static void fm_sda_dir(bool out)
 {
-    I2C_SDA_GPIO_DIR &= ~(1 << I2C_SDA_PIN);
+    if (out) {
+        I2C_SDA_GPIO_DIR |= 1 << I2C_SDA_PIN;
+    } else {
+        I2C_SDA_GPIO_DIR &= ~(1 << I2C_SDA_PIN);
+    }
 }
 
-static void fm_sda_output(void)
+static void fm_scl_out(bool level)
 {
-    I2C_SDA_GPIO_DIR |= 1 << I2C_SDA_PIN;
+    if (level) {
+        I2C_SCL_GPIO(I2C_SCL_PIN) = 1 << I2C_SCL_PIN;
+    } else {
+        I2C_SCL_GPIO(I2C_SCL_PIN) = 0;
+    }
 }
 
-static void fm_scl_input(void)
+static void fm_sda_out(bool level)
 {
-    I2C_SCL_GPIO_DIR &= ~(1 << I2C_SCL_PIN);
+    if (level) {
+        I2C_SDA_GPIO(I2C_SDA_PIN) = 1 << I2C_SDA_PIN;
+    } else {
+        I2C_SDA_GPIO(I2C_SDA_PIN) = 0;
+    }
 }
 
-static void fm_scl_output(void)
+static bool fm_scl_in(void)
 {
-    I2C_SCL_GPIO_DIR |= 1 << I2C_SCL_PIN;
+    return I2C_SCL_GPIO(I2C_SCL_PIN);
 }
 
-static int fm_sda(void)
+static bool fm_sda_in(void)
 {
     return I2C_SDA_GPIO(I2C_SDA_PIN);
 }
 
-static int fm_scl(void)
+static void fm_delay(int delay)
 {
-    return I2C_SCL_GPIO(I2C_SCL_PIN);
-}
-
-/* simple and crude delay, used for all delays in the generic i2c driver */
-static void fm_delay(void)
-{
-    volatile int i;
-
-    /* this loop is uncalibrated and could use more sophistication */
-    for (i = 0; i < 20; i++) {
+    if (delay != 0) {
+        udelay(delay);
     }
 }
 
 /* interface towards the generic i2c driver */
 static const struct i2c_interface fm_i2c_interface = {
-    .scl_hi = fm_scl_hi,
-    .scl_lo = fm_scl_lo,
-    .sda_hi = fm_sda_hi,
-    .sda_lo = fm_sda_lo,
-    .sda_input = fm_sda_input,
-    .sda_output = fm_sda_output,
-    .scl_input = fm_scl_input,
-    .scl_output = fm_scl_output,
-    .scl = fm_scl,
-    .sda = fm_sda,
-
-    .delay_hd_sta = fm_delay,
-    .delay_hd_dat = fm_delay,
-    .delay_su_dat = fm_delay,
-    .delay_su_sto = fm_delay,
-    .delay_su_sta = fm_delay,
-    .delay_thigh = fm_delay
+    .scl_out = fm_scl_out,
+    .scl_dir = fm_scl_dir,
+    .sda_out = fm_sda_out,
+    .sda_dir = fm_sda_dir,
+    .sda_in = fm_sda_in,
+    .scl_in = fm_scl_in,
+    .delay = fm_delay,
+
+    .delay_hd_sta = 1,
+    .delay_hd_dat = 0,
+    .delay_su_dat = 1,
+    .delay_su_sto = 1,
+    .delay_su_sta = 1,
+    .delay_thigh = 2
 };
 
 /* initialise i2c for fmradio */