Finer grained irq masking, blocking for i2c, plus a mutex to prevent conflicting read/writes

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@8922 a1c6a512-1295-4272-9138-f99709370657

4 files changed, 53 insertions, 63 deletions

diff --git a/firmware/drivers/adc.c b/firmware/drivers/adc.c
index f4bdb7a54f..f1a6d7e667 100644
--- a/firmware/drivers/adc.c
+++ b/firmware/drivers/adc.c
@@ -294,10 +294,7 @@ static struct adc_struct adcdata[NUM_ADC_CHANNELS];
 
 static unsigned short adc_scan(struct adc_struct *adc)
 {
-    /* Disable interrupts during the I2C transaction */
-    int old_irq_level = set_irq_level(HIGHEST_IRQ_LEVEL);
     unsigned short data = pcf50605_a2d_read(adc->channelnum);
-    set_irq_level(old_irq_level);
     /* This gives us a 13 bit value corresponding to 0-5.4 volts
      * The range of the value is 13FB-17FA */
     data = (data<<2)+0x13FB;
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);
 }
diff --git a/firmware/drivers/rtc.c b/firmware/drivers/rtc.c
index ecfd2ac6ba..4b4b45826f 100644
--- a/firmware/drivers/rtc.c
+++ b/firmware/drivers/rtc.c
@@ -36,28 +36,18 @@ void rtc_init(void)
 }
 int rtc_read_datetime(unsigned char* buf)
 {
-    int rc;
-    int old_irq_level = set_irq_level(HIGHEST_IRQ_LEVEL);
-
-    rc = pcf50605_read_multiple(0x0a, buf, 7);
-
-    set_irq_level(old_irq_level);
-
-    return rc;
+    return pcf50605_read_multiple(0x0a, buf, 7);
 }
 
 
 int rtc_write_datetime(unsigned char* buf)
 {
     int i;
-    int old_irq_level = set_irq_level(HIGHEST_IRQ_LEVEL);
 
     for (i=0;i<7;i++) {
         pcf50605_write(0x0a+i, buf[i]);
     }
 
-    set_irq_level(old_irq_level);
-
     return 1;
 }
 #elif CONFIG_RTC == RTC_PCF50606
diff --git a/firmware/drivers/wm8758.c b/firmware/drivers/wm8758.c
index 7c9ac77395..3867748417 100644
--- a/firmware/drivers/wm8758.c
+++ b/firmware/drivers/wm8758.c
@@ -86,8 +86,6 @@ void wm8758_write(int reg, int data)
  * Note, I'm using the WM8750 datasheet as its apparently close.
  */
 int wmcodec_init(void) {
-    int old_irq_level = set_irq_level(HIGHEST_IRQ_LEVEL);
-
     /* normal outputs for CDI and I2S pin groups */
     outl(inl(0x70000020) & ~0x300, 0x70000020);
 
@@ -108,7 +106,6 @@ int wmcodec_init(void) {
     /* external dev clock to 24MHz */
     outl(inl(0x70000018) & ~0xc, 0x70000018);
 
-    set_irq_level(old_irq_level);
     return 0;
 }
 
@@ -117,8 +114,6 @@ void wmcodec_enable_output(bool enable)
 {
     if (enable) 
     {
-        int old_irq_level = set_irq_level(HIGHEST_IRQ_LEVEL);
-
         /* reset the I2S controller into known state */
         i2s_reset();
 
@@ -142,7 +137,6 @@ void wmcodec_enable_output(bool enable)
         wm8758_write(LOUTMIX,0x1); /* Enable mixer */
         wm8758_write(ROUTMIX,0x1); /* Enable mixer */
         wmcodec_mute(0);
-        set_irq_level(old_irq_level);
     } else {
         wmcodec_mute(1);
     }
@@ -150,7 +144,6 @@ void wmcodec_enable_output(bool enable)
 
 int wmcodec_set_master_vol(int vol_l, int vol_r)
 {
-    int old_irq_level = set_irq_level(HIGHEST_IRQ_LEVEL);
     /* OUT1 */
     wm8758_write(LOUT1VOL, vol_l);
     wm8758_write(ROUT1VOL, 0x100 | vol_r);
@@ -159,8 +152,6 @@ int wmcodec_set_master_vol(int vol_l, int vol_r)
     wm8758_write(LOUT2VOL, vol_l);
     wm8758_write(ROUT2VOL, 0x100 | vol_r);
     
-    set_irq_level(old_irq_level);
-
     return 0;
 }
 
@@ -204,8 +195,6 @@ void wmcodec_set_treble(int value)
 
 int wmcodec_mute(int mute)
 {
-    int old_irq_level = set_irq_level(HIGHEST_IRQ_LEVEL);
-
     if (mute)
     {
         /* Set DACMU = 1 to soft-mute the audio DACs. */
@@ -215,16 +204,12 @@ int wmcodec_mute(int mute)
         wm8758_write(DACCTRL, 0x0);
     }
 
-    set_irq_level(old_irq_level);
-
     return 0;
 }
 
 /* Nice shutdown of WM8758 codec */
 void wmcodec_close(void)
 {
-    int old_irq_level = set_irq_level(HIGHEST_IRQ_LEVEL);
-
     wmcodec_mute(1);
 
     wm8758_write(PWRMGMT3, 0x0);
@@ -232,8 +217,6 @@ void wmcodec_close(void)
     wm8758_write(PWRMGMT1, 0x0);
 
     wm8758_write(PWRMGMT2, 0x40);
-
-    set_irq_level(old_irq_level);
 }
 
 /* Change the order of the noise shaper, 5th order is recommended above 32kHz */
@@ -245,8 +228,6 @@ void wmcodec_set_nsorder(int order)
 /* Note: Disable output before calling this function */
 void wmcodec_set_sample_rate(int sampling_control)
 {
-    int old_irq_level = set_irq_level(HIGHEST_IRQ_LEVEL);
-
     /**** We force 44.1KHz for now. ****/
     (void)sampling_control;
 
@@ -264,8 +245,6 @@ void wmcodec_set_sample_rate(int sampling_control)
 
     /* set srate */
     wm8758_write(SRATECTRL, (0 << 1));
-
-    set_irq_level(old_irq_level);
 }
 
 void wmcodec_enable_recording(bool source_mic)