1 files changed, 52 insertions, 28 deletions

diff --git a/firmware/drivers/i2c-pp5020.c b/firmware/drivers/i2c-pp5020.c
index 522ddbed77..77671e79d8 100644
--- a/firmware/drivers/i2c-pp5020.c
+++ b/firmware/drivers/i2c-pp5020.c
@@ -57,42 +57,48 @@ static int ipod_i2c_wait_not_busy(void)
          if (!(inb(IPOD_I2C_STATUS) & IPOD_I2C_BUSY)) {
             return 0;
          }
+         yield();
     }
 
     return -1;
 }
 
 
-/* Public functions */
-
-int ipod_i2c_read_byte(unsigned int addr, unsigned int *data)
+static int ipod_i2c_read_byte(unsigned int addr, unsigned int *data)
 {
     if (ipod_i2c_wait_not_busy() < 0)
     {
         return -1;
     }
 
-    /* clear top 15 bits, left shift 1, or in 0x1 for a read */
-    outb(((addr << 17) >> 16) | 0x1, IPOD_I2C_ADDR);
+    {
+        int old_irq_level = set_irq_level(HIGHEST_IRQ_LEVEL);
 
-    outb(inb(IPOD_I2C_CTRL) | 0x20, IPOD_I2C_CTRL);
+        /* clear top 15 bits, left shift 1, or in 0x1 for a read */
+        outb(((addr << 17) >> 16) | 0x1, IPOD_I2C_ADDR);
 
-    outb(inb(IPOD_I2C_CTRL) | IPOD_I2C_SEND, IPOD_I2C_CTRL);
+        outb(inb(IPOD_I2C_CTRL) | 0x20, IPOD_I2C_CTRL);
 
-    if (ipod_i2c_wait_not_busy() < 0)
-    {
-        return -1;
-    }
+        outb(inb(IPOD_I2C_CTRL) | IPOD_I2C_SEND, IPOD_I2C_CTRL);
 
-    if (data)
-    {
-        *data = inb(IPOD_I2C_DATA0);
+        set_irq_level(old_irq_level);
+
+        if (data)
+        {
+            if (ipod_i2c_wait_not_busy() < 0)
+            {
+                return -1;
+            }
+            old_irq_level = set_irq_level(HIGHEST_IRQ_LEVEL);
+            *data = inb(IPOD_I2C_DATA0);
+            set_irq_level(old_irq_level);
+        }
     }
 
     return 0;
 }
 
-int ipod_i2c_send_bytes(unsigned int addr, unsigned int len, unsigned char *data)
+static int ipod_i2c_send_bytes(unsigned int addr, unsigned int len, unsigned char *data)
 {
     int data_addr;
     unsigned int i;
@@ -107,26 +113,32 @@ int ipod_i2c_send_bytes(unsigned int addr, unsigned int len, unsigned char *data
         return -2;
     }
 
-    /* clear top 15 bits, left shift 1 */
-    outb((addr << 17) >> 16, IPOD_I2C_ADDR);
+    {
+        int old_irq_level = set_irq_level(HIGHEST_IRQ_LEVEL);
 
-    outb(inb(IPOD_I2C_CTRL) & ~0x20, IPOD_I2C_CTRL);
+        /* clear top 15 bits, left shift 1 */
+        outb((addr << 17) >> 16, IPOD_I2C_ADDR);
 
-    data_addr = IPOD_I2C_DATA0;
-    for ( i = 0; i < len; i++ )
-    {
-        outb(*data++, data_addr);
-        data_addr += 4;
-    }
+        outb(inb(IPOD_I2C_CTRL) & ~0x20, IPOD_I2C_CTRL);
+
+        data_addr = IPOD_I2C_DATA0;
+        for ( i = 0; i < len; i++ )
+        {
+            outb(*data++, data_addr);
+            data_addr += 4;
+        }
 
-    outb((inb(IPOD_I2C_CTRL) & ~0x26) | ((len-1) << 1), IPOD_I2C_CTRL);
+        outb((inb(IPOD_I2C_CTRL) & ~0x26) | ((len-1) << 1), IPOD_I2C_CTRL);
 
-    outb(inb(IPOD_I2C_CTRL) | IPOD_I2C_SEND, IPOD_I2C_CTRL);
+        outb(inb(IPOD_I2C_CTRL) | IPOD_I2C_SEND, IPOD_I2C_CTRL);
+
+        set_irq_level(old_irq_level);
+    }
 
     return 0x0;
 }
 
-int ipod_i2c_send_byte(unsigned int addr, int data0)
+static int ipod_i2c_send_byte(unsigned int addr, int data0)
 {
     unsigned char data[1];
 
@@ -135,25 +147,35 @@ int ipod_i2c_send_byte(unsigned int addr, int data0)
     return ipod_i2c_send_bytes(addr, 1, data);
 }
 
+/* Public functions */
+static struct mutex i2c_mutex;
 
 int i2c_readbyte(unsigned int dev_addr, int addr)
 {
+    int retval;
     int data;
 
+    mutex_lock(&i2c_mutex);
     ipod_i2c_send_byte(dev_addr, addr);
     ipod_i2c_read_byte(dev_addr, &data);
+    mutex_unlock(&i2c_mutex);
 
     return data;
 }
 
 int ipod_i2c_send(unsigned int addr, int data0, int data1)
 {
+        int retval;
         unsigned char data[2];
 
         data[0] = data0;
         data[1] = data1;
 
-        return ipod_i2c_send_bytes(addr, 2, data);
+        mutex_lock(&i2c_mutex);
+        retval = ipod_i2c_send_bytes(addr, 2, data);
+        mutex_unlock(&i2c_mutex);
+
+        return retval;
 }
 
 void i2c_init(void)
@@ -175,5 +197,7 @@ void i2c_init(void)
    outl(0x0, 0x600060a4);
    outl(0x80 | (0 << 8), 0x600060a4);
 
+   mutex_init(&i2c_mutex);
+   
    i2c_readbyte(0x8, 0);
 }