Simplify generic_i2c, removing the link between i2c address and i2c interface, adding the concept of an i2c bus index.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@20193 a1c6a512-1295-4272-9138-f99709370657

4 files changed, 39 insertions, 58 deletions

diff --git a/firmware/drivers/generic_i2c.c b/firmware/drivers/generic_i2c.c
index dcbe46f..206ded9 100644
--- a/firmware/drivers/generic_i2c.c
+++ b/firmware/drivers/generic_i2c.c
@@ -28,9 +28,9 @@
 #define MAX_I2C_INTERFACES 5
 
 static int i2c_num_ifs = 0;
-static struct i2c_interface *i2c_if[MAX_I2C_INTERFACES];
+static const struct i2c_interface *i2c_if[MAX_I2C_INTERFACES];
 
-static void i2c_start(struct i2c_interface *iface)
+static void i2c_start(const struct i2c_interface *iface)
 {
     iface->sda_output();
 
@@ -41,7 +41,7 @@ static void i2c_start(struct i2c_interface *iface)
     iface->scl_lo();
 }
 
-static void i2c_stop(struct i2c_interface *iface)
+static void i2c_stop(const struct i2c_interface *iface)
 {
     iface->sda_output();
 
@@ -51,7 +51,7 @@ static void i2c_stop(struct i2c_interface *iface)
     iface->sda_hi();
 }
 
-static void i2c_ack(struct i2c_interface *iface, bool ack)
+static void i2c_ack(const struct i2c_interface *iface, bool ack)
 {
     iface->sda_output();
     iface->scl_lo();
@@ -66,7 +66,7 @@ static void i2c_ack(struct i2c_interface *iface, bool ack)
     iface->scl_lo();
 }
 
-static int i2c_getack(struct i2c_interface *iface)
+static int i2c_getack(const struct i2c_interface *iface)
 {
     int ret = 1;
 
@@ -85,7 +85,7 @@ static int i2c_getack(struct i2c_interface *iface)
     return ret;
 }
 
-static unsigned char i2c_inb(struct i2c_interface *iface, bool ack)
+static unsigned char i2c_inb(const struct i2c_interface *iface, bool ack)
 {
     int i;
     unsigned char byte = 0;
@@ -107,7 +107,7 @@ static unsigned char i2c_inb(struct i2c_interface *iface, bool ack)
     return byte;
 }
 
-static int i2c_outb(struct i2c_interface *iface, unsigned char byte)
+static int i2c_outb(const struct i2c_interface *iface, unsigned char byte)
 {
     int i;
 
@@ -127,32 +127,19 @@ static int i2c_outb(struct i2c_interface *iface, unsigned char byte)
    }
 
    iface->sda_hi();
-   
-   return i2c_getack(iface);
-}
-
-static struct i2c_interface *find_if(int address)
-{
-    int i;
 
-    for(i = 0;i < i2c_num_ifs;i++) {
-        if(i2c_if[i]->address == address)
-            return i2c_if[i];
-    }
-    return NULL;
+   return i2c_getack(iface);
 }
 
-int i2c_write_data(int bus_address, int address,
+int i2c_write_data(int bus_index, int bus_address, int address,
                    const unsigned char* buf, int count)
 {
     int i;
     int ret = 0;
-    struct i2c_interface *iface = find_if(bus_address);
-    if(!iface)
-        return -1;
+    const struct i2c_interface *iface = i2c_if[bus_index];;
 
     i2c_start(iface);
-    if (!i2c_outb(iface, iface->address & 0xfe))
+    if (!i2c_outb(iface, bus_address & 0xfe))
     {
         ret = -2;
         goto end;
@@ -181,19 +168,17 @@ end:
     return ret;
 }
 
-int i2c_read_data(int bus_address, int address,
+int i2c_read_data(int bus_index, int bus_address, int address,
                   unsigned char* buf, int count)
 {
     int i;
     int ret = 0;
-    struct i2c_interface *iface = find_if(bus_address);
-    if(!iface)
-        return -1;
+    const struct i2c_interface *iface = i2c_if[bus_index];;
 
     if (address != -1)
     {
         i2c_start(iface);
-        if (!i2c_outb(iface, iface->address & 0xfe))
+        if (!i2c_outb(iface, bus_address & 0xfe))
         {
             ret = -2;
             goto end;
@@ -206,7 +191,7 @@ int i2c_read_data(int bus_address, int address,
     }
 
     i2c_start(iface);
-    if (!i2c_outb(iface, iface->address | 1))
+    if (!i2c_outb(iface, bus_address | 1))
     {
         ret = -4;
         goto end;
@@ -222,14 +207,18 @@ end:
     return ret;
 }
 
-int i2c_add_node(struct i2c_interface *iface)
+/* returns bus index which can be used as a handle, or <0 on error */
+int i2c_add_node(const struct i2c_interface *iface)
 {
+    int bus_index;
+
     if (i2c_num_ifs == MAX_I2C_INTERFACES)
         return -1;
 
-    i2c_if[i2c_num_ifs++] = iface;
+    bus_index = i2c_num_ifs++;
+    i2c_if[bus_index] = iface;
 
     iface->scl_output();
 
-    return 0;
+    return bus_index;
 }
diff --git a/firmware/export/generic_i2c.h b/firmware/export/generic_i2c.h
index f387285..6679b78 100644
--- a/firmware/export/generic_i2c.h
+++ b/firmware/export/generic_i2c.h
@@ -23,9 +23,6 @@
 
 struct i2c_interface
 {
-    unsigned char address; /* Address of the chip that this interface
-                              describes */
-
     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 */
@@ -47,9 +44,11 @@ struct i2c_interface
     void (*delay_thigh)(void);  /* SCL high period (tHIGH)     4.0us/0.6us */
 };
 
-extern int i2c_add_node(struct i2c_interface *iface);
-extern int i2c_write_data(int bus_address, int address,
-                          const unsigned char* buf, int count);
-extern int i2c_read_data(int bus_address, int address,
-                         unsigned char* buf, int count);
-#endif
+int i2c_add_node(const struct i2c_interface *iface);
+int i2c_write_data(int bus_index, int bus_address, int address,
+                   const unsigned char* buf, int count);
+int i2c_read_data(int bus_index, int bus_address, int address,
+                  unsigned char* buf, int count);
+
+#endif /* _GEN_I2C_ */
+
diff --git a/firmware/target/arm/as3525/fmradio-i2c-as3525.c b/firmware/target/arm/as3525/fmradio-i2c-as3525.c
index 72775ed..528e8c7 100644
--- a/firmware/target/arm/as3525/fmradio-i2c-as3525.c
+++ b/firmware/target/arm/as3525/fmradio-i2c-as3525.c
@@ -22,7 +22,7 @@
 /*
     This is the fmradio_i2c interface, used by the radio driver
     to communicate with the radio tuner chip.
-    
+
     It is implemented using the generic i2c driver, which does "bit-banged"
     I2C with a couple of GPIO pins.
  */
@@ -53,6 +53,8 @@
 #error no FM I2C GPIOPIN defines
 #endif
 
+static int fm_i2c_bus;
+
 static void fm_scl_hi(void)
 {
     I2C_GPIO(I2C_SCL_PIN) = 1 << I2C_SCL_PIN;
@@ -107,22 +109,14 @@ static int fm_scl(void)
 static void fm_delay(void)
 {
     volatile int i;
-    
+
     /* this loop is uncalibrated and could use more sophistication */
     for (i = 0; i < 100; i++) {
     }
 }
 
 /* interface towards the generic i2c driver */
-static struct i2c_interface fm_i2c_interface = {
-#if     defined(SANSA_CLIP) || defined(SANSA_FUZE) || defined(SANSA_E200V2)
-    .address = 0x10 << 1,
-#elif   defined(SANSA_M200V4)
-    .address = 0xC0,
-#elif
-#error no fm i2c address defined
-#endif
-    
+static const struct i2c_interface fm_i2c_interface = {
     .scl_hi = fm_scl_hi,
     .scl_lo = fm_scl_lo,
     .sda_hi = fm_sda_hi,
@@ -133,7 +127,7 @@ static struct i2c_interface fm_i2c_interface = {
     .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,
@@ -145,17 +139,17 @@ static struct i2c_interface fm_i2c_interface = {
 /* initialise i2c for fmradio */
 void fmradio_i2c_init(void)
 {
-    i2c_add_node(&fm_i2c_interface);
+    fm_i2c_bus = i2c_add_node(&fm_i2c_interface);
 }
 
 int fmradio_i2c_write(unsigned char address, const unsigned char* buf, int count)
 {
-    return i2c_write_data(address, -1, buf, count);
+    return i2c_write_data(fm_i2c_bus, address, -1, buf, count);
 }
 
 int fmradio_i2c_read(unsigned char address, unsigned char* buf, int count)
 {
-    return i2c_read_data(address, -1, buf, count);
+    return i2c_read_data(fm_i2c_bus, address, -1, buf, count);
 }
 
 
diff --git a/firmware/target/mips/ingenic_jz47xx/i2c-jz4740.c b/firmware/target/mips/ingenic_jz47xx/i2c-jz4740.c
index 4565420..b97448f 100644
--- a/firmware/target/mips/ingenic_jz47xx/i2c-jz4740.c
+++ b/firmware/target/mips/ingenic_jz47xx/i2c-jz4740.c
@@ -46,7 +46,6 @@
 #include "system.h"
 #include "jz4740.h"
 #include "logf.h"
-#include "generic_i2c.h"
 
 
 /* I2C protocol */