[Qemu-devel] [PATCH 1/2] i2c: Introduce device address mask

[Jan Kiszka]

Some devices react on multiple addresses. To emulate this, we could
register them multiple times, but that is cumbersome. The AT24C16, e.g.
listens on 8 different addresses.

Instead, introduce a device address mask that is applied on the
transmitted address before matching it against the stored one. Moreover,
the transmitted address is passed as additional parameter to the event
callback of the device.

Signed-off-by: Jan Kiszka <address@hidden>
---
 hw/ds1338.c   |    2 +-
 hw/i2c.c      |    9 +++++----
 hw/i2c.h      |    3 ++-
 hw/lm832x.c   |    2 +-
 hw/max7310.c  |    2 +-
 hw/pxa2xx.c   |    3 ++-
 hw/smbus.c    |    2 +-
 hw/ssd0303.c  |    2 +-
 hw/tmp105.c   |    2 +-
 hw/tosa.c     |    2 +-
 hw/twl92230.c |    2 +-
 hw/wm8750.c   |    2 +-
 hw/z2.c       |    2 +-
 13 files changed, 19 insertions(+), 16 deletions(-)

diff --git a/hw/ds1338.c b/hw/ds1338.c
index b576d56..59fcc01 100644
--- a/hw/ds1338.c
+++ b/hw/ds1338.c
@@ -75,7 +75,7 @@ static void inc_regptr(DS1338State *s)
     }
 }
 
-static void ds1338_event(I2CSlave *i2c, enum i2c_event event)
+static void ds1338_event(I2CSlave *i2c, enum i2c_event event, uint8_t param)
 {
     DS1338State *s = FROM_I2C_SLAVE(DS1338State, i2c);
 
diff --git a/hw/i2c.c b/hw/i2c.c
index 296bece..72b8f07 100644
--- a/hw/i2c.c
+++ b/hw/i2c.c
@@ -93,7 +93,7 @@ int i2c_start_transfer(i2c_bus *bus, uint8_t address, int 
recv)
     QTAILQ_FOREACH(kid, &bus->qbus.children, sibling) {
         DeviceState *qdev = kid->child;
         I2CSlave *candidate = I2C_SLAVE_FROM_QDEV(qdev);
-        if (candidate->address == address) {
+        if (candidate->address == (address & candidate->address_mask)) {
             slave = candidate;
             break;
         }
@@ -108,7 +108,7 @@ int i2c_start_transfer(i2c_bus *bus, uint8_t address, int 
recv)
        start condition.  */
     bus->current_dev = slave;
     if (sc->event) {
-        sc->event(slave, recv ? I2C_START_RECV : I2C_START_SEND);
+        sc->event(slave, recv ? I2C_START_RECV : I2C_START_SEND, address);
     }
     return 0;
 }
@@ -124,7 +124,7 @@ void i2c_end_transfer(i2c_bus *bus)
 
     sc = I2C_SLAVE_GET_CLASS(dev);
     if (sc->event) {
-        sc->event(dev, I2C_FINISH);
+        sc->event(dev, I2C_FINISH, 0);
     }
 
     bus->current_dev = NULL;
@@ -175,7 +175,7 @@ void i2c_nack(i2c_bus *bus)
 
     sc = I2C_SLAVE_GET_CLASS(dev);
     if (sc->event) {
-        sc->event(dev, I2C_NACK);
+        sc->event(dev, I2C_NACK, 0);
     }
 }
 
@@ -207,6 +207,7 @@ static int i2c_slave_qdev_init(DeviceState *dev)
     I2CSlave *s = I2C_SLAVE_FROM_QDEV(dev);
     I2CSlaveClass *sc = I2C_SLAVE_GET_CLASS(s);
 
+    s->address_mask = 0x7f;
     return sc->init(s);
 }
 
diff --git a/hw/i2c.h b/hw/i2c.h
index 0f5682b..6cf164b 100644
--- a/hw/i2c.h
+++ b/hw/i2c.h
@@ -39,7 +39,7 @@ typedef struct I2CSlaveClass
     int (*recv)(I2CSlave *s);
 
     /* Notify the slave of a bus state change.  */
-    void (*event)(I2CSlave *s, enum i2c_event event);
+    void (*event)(I2CSlave *s, enum i2c_event event, uint8_t param);
 } I2CSlaveClass;
 
 struct I2CSlave
@@ -48,6 +48,7 @@ struct I2CSlave
 
     /* Remaining fields for internal use by the I2C code.  */
     uint8_t address;
+    uint8_t address_mask;
 };
 
 i2c_bus *i2c_init_bus(DeviceState *parent, const char *name);
diff --git a/hw/lm832x.c b/hw/lm832x.c
index 8e09f9b..d69aa4b 100644
--- a/hw/lm832x.c
+++ b/hw/lm832x.c
@@ -378,7 +378,7 @@ static void lm_kbd_write(LM823KbdState *s, int reg, int 
byte, uint8_t value)
     }
 }
 
-static void lm_i2c_event(I2CSlave *i2c, enum i2c_event event)
+static void lm_i2c_event(I2CSlave *i2c, enum i2c_event event, uint8_t param)
 {
     LM823KbdState *s = FROM_I2C_SLAVE(LM823KbdState, i2c);
 
diff --git a/hw/max7310.c b/hw/max7310.c
index 1ed18ba..63999be 100644
--- a/hw/max7310.c
+++ b/hw/max7310.c
@@ -123,7 +123,7 @@ static int max7310_tx(I2CSlave *i2c, uint8_t data)
     return 0;
 }
 
-static void max7310_event(I2CSlave *i2c, enum i2c_event event)
+static void max7310_event(I2CSlave *i2c, enum i2c_event event, uint8_t param)
 {
     MAX7310State *s = (MAX7310State *) i2c;
     s->len = 0;
diff --git a/hw/pxa2xx.c b/hw/pxa2xx.c
index e616979..fb1fd0d 100644
--- a/hw/pxa2xx.c
+++ b/hw/pxa2xx.c
@@ -1239,7 +1239,8 @@ static void pxa2xx_i2c_update(PXA2xxI2CState *s)
 }
 
 /* These are only stubs now.  */
-static void pxa2xx_i2c_event(I2CSlave *i2c, enum i2c_event event)
+static void pxa2xx_i2c_event(I2CSlave *i2c, enum i2c_event event,
+                             uint8_t param)
 {
     PXA2xxI2CSlaveState *slave = FROM_I2C_SLAVE(PXA2xxI2CSlaveState, i2c);
     PXA2xxI2CState *s = slave->host;
diff --git a/hw/smbus.c b/hw/smbus.c
index e3cf6a2..7d070d9 100644
--- a/hw/smbus.c
+++ b/hw/smbus.c
@@ -66,7 +66,7 @@ static void smbus_do_write(SMBusDevice *dev)
     }
 }
 
-static void smbus_i2c_event(I2CSlave *s, enum i2c_event event)
+static void smbus_i2c_event(I2CSlave *s, enum i2c_event event, uint8_t param)
 {
     SMBusDevice *dev = SMBUS_DEVICE(s);
 
diff --git a/hw/ssd0303.c b/hw/ssd0303.c
index d7fd828..19a8d66 100644
--- a/hw/ssd0303.c
+++ b/hw/ssd0303.c
@@ -173,7 +173,7 @@ static int ssd0303_send(I2CSlave *i2c, uint8_t data)
     return 0;
 }
 
-static void ssd0303_event(I2CSlave *i2c, enum i2c_event event)
+static void ssd0303_event(I2CSlave *i2c, enum i2c_event event, uint8_t param)
 {
     ssd0303_state *s = (ssd0303_state *)i2c;
     switch (event) {
diff --git a/hw/tmp105.c b/hw/tmp105.c
index 8e8dbd9..a6dc39a 100644
--- a/hw/tmp105.c
+++ b/hw/tmp105.c
@@ -163,7 +163,7 @@ static int tmp105_tx(I2CSlave *i2c, uint8_t data)
     return 0;
 }
 
-static void tmp105_event(I2CSlave *i2c, enum i2c_event event)
+static void tmp105_event(I2CSlave *i2c, enum i2c_event event, uint8_t param)
 {
     TMP105State *s = (TMP105State *) i2c;
 
diff --git a/hw/tosa.c b/hw/tosa.c
index 512278c..2d2ac54 100644
--- a/hw/tosa.c
+++ b/hw/tosa.c
@@ -157,7 +157,7 @@ static int tosa_dac_send(I2CSlave *i2c, uint8_t data)
     return 0;
 }
 
-static void tosa_dac_event(I2CSlave *i2c, enum i2c_event event)
+static void tosa_dac_event(I2CSlave *i2c, enum i2c_event event, uint8_t param)
 {
     TosaDACState *s = FROM_I2C_SLAVE(TosaDACState, i2c);
     s->len = 0;
diff --git a/hw/twl92230.c b/hw/twl92230.c
index 0d70d84..898d3a1 100644
--- a/hw/twl92230.c
+++ b/hw/twl92230.c
@@ -706,7 +706,7 @@ static void menelaus_write(void *opaque, uint8_t addr, 
uint8_t value)
     }
 }
 
-static void menelaus_event(I2CSlave *i2c, enum i2c_event event)
+static void menelaus_event(I2CSlave *i2c, enum i2c_event event, uint8_t param)
 {
     MenelausState *s = (MenelausState *) i2c;
 
diff --git a/hw/wm8750.c b/hw/wm8750.c
index 44f138f..9358342 100644
--- a/hw/wm8750.c
+++ b/hw/wm8750.c
@@ -297,7 +297,7 @@ static void wm8750_reset(I2CSlave *i2c)
     s->i2c_len = 0;
 }
 
-static void wm8750_event(I2CSlave *i2c, enum i2c_event event)
+static void wm8750_event(I2CSlave *i2c, enum i2c_event event, uint8_t param)
 {
     WM8750State *s = (WM8750State *) i2c;
 
diff --git a/hw/z2.c b/hw/z2.c
index f62b806..ca69f60 100644
--- a/hw/z2.c
+++ b/hw/z2.c
@@ -216,7 +216,7 @@ static int aer915_send(I2CSlave *i2c, uint8_t data)
     return 0;
 }
 
-static void aer915_event(I2CSlave *i2c, enum i2c_event event)
+static void aer915_event(I2CSlave *i2c, enum i2c_event event, uint8_t param)
 {
     AER915State *s = FROM_I2C_SLAVE(AER915State, i2c);
     switch (event) {
-- 
1.7.3.4