Merge remote-tracking branch 'remotes/cminyard/tags/for-qemu-i2c-5' into staging

Minor changes to:

Add an SMBus config entry

Cleanup/simplify/document some I2C interfaces

# gpg: Signature made Thu 16 Jul 2020 18:46:55 BST
# gpg:                using RSA key FD0D5CE67CE0F59A6688268661F38C90919BFF81
# gpg: Good signature from "Corey Minyard <cminyard@mvista.com>" [unknown]
# gpg:                 aka "Corey Minyard <minyard@acm.org>" [unknown]
# gpg:                 aka "Corey Minyard <corey@minyard.net>" [unknown]
# gpg:                 aka "Corey Minyard <minyard@mvista.com>" [unknown]
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg:          There is no indication that the signature belongs to the owner.
# Primary key fingerprint: FD0D 5CE6 7CE0 F59A 6688  2686 61F3 8C90 919B FF81

* remotes/cminyard/tags/for-qemu-i2c-5:
  hw/i2c: Document the I2C qdev helpers
  hw/i2c: Rename i2c_create_slave() as i2c_slave_create_simple()
  hw/i2c: Rename i2c_realize_and_unref() as i2c_slave_realize_and_unref()
  hw/i2c: Rename i2c_try_create_slave() as i2c_slave_new()
  hw/i2c/aspeed_i2c: Simplify aspeed_i2c_get_bus()
  hw/i2c/Kconfig: Add an entry for the SMBus

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

20 files changed, 131 insertions, 77 deletions

diff --git a/hw/arm/aspeed.c b/hw/arm/aspeed.c
index 6a3a345a6f..fcb1a7cd87 100644
--- a/hw/arm/aspeed.c
+++ b/hw/arm/aspeed.c
@@ -386,14 +386,14 @@ static void palmetto_bmc_i2c_init(AspeedMachineState *bmc)
 
     /* The palmetto platform expects a ds3231 RTC but a ds1338 is
      * enough to provide basic RTC features. Alarms will be missing */
-    i2c_create_slave(aspeed_i2c_get_bus(DEVICE(&soc->i2c), 0), "ds1338", 0x68);
+    i2c_slave_create_simple(aspeed_i2c_get_bus(&soc->i2c, 0), "ds1338", 0x68);
 
-    smbus_eeprom_init_one(aspeed_i2c_get_bus(DEVICE(&soc->i2c), 0), 0x50,
+    smbus_eeprom_init_one(aspeed_i2c_get_bus(&soc->i2c, 0), 0x50,
                           eeprom_buf);
 
     /* add a TMP423 temperature sensor */
-    dev = i2c_create_slave(aspeed_i2c_get_bus(DEVICE(&soc->i2c), 2),
-                           "tmp423", 0x4c);
+    dev = DEVICE(i2c_slave_create_simple(aspeed_i2c_get_bus(&soc->i2c, 2),
+                                         "tmp423", 0x4c));
     object_property_set_int(OBJECT(dev), "temperature0", 31000, &error_abort);
     object_property_set_int(OBJECT(dev), "temperature1", 28000, &error_abort);
     object_property_set_int(OBJECT(dev), "temperature2", 20000, &error_abort);
@@ -405,16 +405,16 @@ static void ast2500_evb_i2c_init(AspeedMachineState *bmc)
     AspeedSoCState *soc = &bmc->soc;
     uint8_t *eeprom_buf = g_malloc0(8 * 1024);
 
-    smbus_eeprom_init_one(aspeed_i2c_get_bus(DEVICE(&soc->i2c), 3), 0x50,
+    smbus_eeprom_init_one(aspeed_i2c_get_bus(&soc->i2c, 3), 0x50,
                           eeprom_buf);
 
     /* The AST2500 EVB expects a LM75 but a TMP105 is compatible */
-    i2c_create_slave(aspeed_i2c_get_bus(DEVICE(&soc->i2c), 7),
+    i2c_slave_create_simple(aspeed_i2c_get_bus(&soc->i2c, 7),
                      TYPE_TMP105, 0x4d);
 
     /* The AST2500 EVB does not have an RTC. Let's pretend that one is
      * plugged on the I2C bus header */
-    i2c_create_slave(aspeed_i2c_get_bus(DEVICE(&soc->i2c), 11), "ds1338", 0x32);
+    i2c_slave_create_simple(aspeed_i2c_get_bus(&soc->i2c, 11), "ds1338", 0x32);
 }
 
 static void ast2600_evb_i2c_init(AspeedMachineState *bmc)
@@ -429,36 +429,36 @@ static void romulus_bmc_i2c_init(AspeedMachineState *bmc)
 
     /* The romulus board expects Epson RX8900 I2C RTC but a ds1338 is
      * good enough */
-    i2c_create_slave(aspeed_i2c_get_bus(DEVICE(&soc->i2c), 11), "ds1338", 0x32);
+    i2c_slave_create_simple(aspeed_i2c_get_bus(&soc->i2c, 11), "ds1338", 0x32);
 }
 
 static void swift_bmc_i2c_init(AspeedMachineState *bmc)
 {
     AspeedSoCState *soc = &bmc->soc;
 
-    i2c_create_slave(aspeed_i2c_get_bus(DEVICE(&soc->i2c), 3), "pca9552", 0x60);
+    i2c_slave_create_simple(aspeed_i2c_get_bus(&soc->i2c, 3), "pca9552", 0x60);
 
     /* The swift board expects a TMP275 but a TMP105 is compatible */
-    i2c_create_slave(aspeed_i2c_get_bus(DEVICE(&soc->i2c), 7), "tmp105", 0x48);
+    i2c_slave_create_simple(aspeed_i2c_get_bus(&soc->i2c, 7), "tmp105", 0x48);
     /* The swift board expects a pca9551 but a pca9552 is compatible */
-    i2c_create_slave(aspeed_i2c_get_bus(DEVICE(&soc->i2c), 7), "pca9552", 0x60);
+    i2c_slave_create_simple(aspeed_i2c_get_bus(&soc->i2c, 7), "pca9552", 0x60);
 
     /* The swift board expects an Epson RX8900 RTC but a ds1338 is compatible */
-    i2c_create_slave(aspeed_i2c_get_bus(DEVICE(&soc->i2c), 8), "ds1338", 0x32);
-    i2c_create_slave(aspeed_i2c_get_bus(DEVICE(&soc->i2c), 8), "pca9552", 0x60);
+    i2c_slave_create_simple(aspeed_i2c_get_bus(&soc->i2c, 8), "ds1338", 0x32);
+    i2c_slave_create_simple(aspeed_i2c_get_bus(&soc->i2c, 8), "pca9552", 0x60);
 
-    i2c_create_slave(aspeed_i2c_get_bus(DEVICE(&soc->i2c), 9), "tmp423", 0x4c);
+    i2c_slave_create_simple(aspeed_i2c_get_bus(&soc->i2c, 9), "tmp423", 0x4c);
     /* The swift board expects a pca9539 but a pca9552 is compatible */
-    i2c_create_slave(aspeed_i2c_get_bus(DEVICE(&soc->i2c), 9), "pca9552", 0x74);
+    i2c_slave_create_simple(aspeed_i2c_get_bus(&soc->i2c, 9), "pca9552", 0x74);
 
-    i2c_create_slave(aspeed_i2c_get_bus(DEVICE(&soc->i2c), 10), "tmp423", 0x4c);
+    i2c_slave_create_simple(aspeed_i2c_get_bus(&soc->i2c, 10), "tmp423", 0x4c);
     /* The swift board expects a pca9539 but a pca9552 is compatible */
-    i2c_create_slave(aspeed_i2c_get_bus(DEVICE(&soc->i2c), 10), "pca9552",
+    i2c_slave_create_simple(aspeed_i2c_get_bus(&soc->i2c, 10), "pca9552",
                      0x74);
 
     /* The swift board expects a TMP275 but a TMP105 is compatible */
-    i2c_create_slave(aspeed_i2c_get_bus(DEVICE(&soc->i2c), 12), "tmp105", 0x48);
-    i2c_create_slave(aspeed_i2c_get_bus(DEVICE(&soc->i2c), 12), "tmp105", 0x4a);
+    i2c_slave_create_simple(aspeed_i2c_get_bus(&soc->i2c, 12), "tmp105", 0x48);
+    i2c_slave_create_simple(aspeed_i2c_get_bus(&soc->i2c, 12), "tmp105", 0x4a);
 }
 
 static void sonorapass_bmc_i2c_init(AspeedMachineState *bmc)
@@ -466,32 +466,32 @@ static void sonorapass_bmc_i2c_init(AspeedMachineState *bmc)
     AspeedSoCState *soc = &bmc->soc;
 
     /* bus 2 : */
-    i2c_create_slave(aspeed_i2c_get_bus(DEVICE(&soc->i2c), 2), "tmp105", 0x48);
-    i2c_create_slave(aspeed_i2c_get_bus(DEVICE(&soc->i2c), 2), "tmp105", 0x49);
+    i2c_slave_create_simple(aspeed_i2c_get_bus(&soc->i2c, 2), "tmp105", 0x48);
+    i2c_slave_create_simple(aspeed_i2c_get_bus(&soc->i2c, 2), "tmp105", 0x49);
     /* bus 2 : pca9546 @ 0x73 */
 
     /* bus 3 : pca9548 @ 0x70 */
 
     /* bus 4 : */
     uint8_t *eeprom4_54 = g_malloc0(8 * 1024);
-    smbus_eeprom_init_one(aspeed_i2c_get_bus(DEVICE(&soc->i2c), 4), 0x54,
+    smbus_eeprom_init_one(aspeed_i2c_get_bus(&soc->i2c, 4), 0x54,
                           eeprom4_54);
     /* PCA9539 @ 0x76, but PCA9552 is compatible */
-    i2c_create_slave(aspeed_i2c_get_bus(DEVICE(&soc->i2c), 4), "pca9552", 0x76);
+    i2c_slave_create_simple(aspeed_i2c_get_bus(&soc->i2c, 4), "pca9552", 0x76);
     /* PCA9539 @ 0x77, but PCA9552 is compatible */
-    i2c_create_slave(aspeed_i2c_get_bus(DEVICE(&soc->i2c), 4), "pca9552", 0x77);
+    i2c_slave_create_simple(aspeed_i2c_get_bus(&soc->i2c, 4), "pca9552", 0x77);
 
     /* bus 6 : */
-    i2c_create_slave(aspeed_i2c_get_bus(DEVICE(&soc->i2c), 6), "tmp105", 0x48);
-    i2c_create_slave(aspeed_i2c_get_bus(DEVICE(&soc->i2c), 6), "tmp105", 0x49);
+    i2c_slave_create_simple(aspeed_i2c_get_bus(&soc->i2c, 6), "tmp105", 0x48);
+    i2c_slave_create_simple(aspeed_i2c_get_bus(&soc->i2c, 6), "tmp105", 0x49);
     /* bus 6 : pca9546 @ 0x73 */
 
     /* bus 8 : */
     uint8_t *eeprom8_56 = g_malloc0(8 * 1024);
-    smbus_eeprom_init_one(aspeed_i2c_get_bus(DEVICE(&soc->i2c), 8), 0x56,
+    smbus_eeprom_init_one(aspeed_i2c_get_bus(&soc->i2c, 8), 0x56,
                           eeprom8_56);
-    i2c_create_slave(aspeed_i2c_get_bus(DEVICE(&soc->i2c), 8), "pca9552", 0x60);
-    i2c_create_slave(aspeed_i2c_get_bus(DEVICE(&soc->i2c), 8), "pca9552", 0x61);
+    i2c_slave_create_simple(aspeed_i2c_get_bus(&soc->i2c, 8), "pca9552", 0x60);
+    i2c_slave_create_simple(aspeed_i2c_get_bus(&soc->i2c, 8), "pca9552", 0x61);
     /* bus 8 : adc128d818 @ 0x1d */
     /* bus 8 : adc128d818 @ 0x1f */
 
@@ -514,28 +514,30 @@ static void witherspoon_bmc_i2c_init(AspeedMachineState *bmc)
     /* Bus 3: TODO bmp280@77 */
     /* Bus 3: TODO max31785@52 */
     /* Bus 3: TODO dps310@76 */
-    dev = i2c_try_create_slave(TYPE_PCA9552, 0x60);
+    dev = DEVICE(i2c_slave_new(TYPE_PCA9552, 0x60));
     qdev_prop_set_string(dev, "description", "pca1");
-    i2c_realize_and_unref(dev, aspeed_i2c_get_bus(DEVICE(&soc->i2c), 3),
-                          &error_fatal);
+    i2c_slave_realize_and_unref(I2C_SLAVE(dev),
+                                aspeed_i2c_get_bus(&soc->i2c, 3),
+                                &error_fatal);
 
-    i2c_create_slave(aspeed_i2c_get_bus(DEVICE(&soc->i2c), 4), "tmp423", 0x4c);
-    i2c_create_slave(aspeed_i2c_get_bus(DEVICE(&soc->i2c), 5), "tmp423", 0x4c);
+    i2c_slave_create_simple(aspeed_i2c_get_bus(&soc->i2c, 4), "tmp423", 0x4c);
+    i2c_slave_create_simple(aspeed_i2c_get_bus(&soc->i2c, 5), "tmp423", 0x4c);
 
     /* The Witherspoon expects a TMP275 but a TMP105 is compatible */
-    i2c_create_slave(aspeed_i2c_get_bus(DEVICE(&soc->i2c), 9), TYPE_TMP105,
+    i2c_slave_create_simple(aspeed_i2c_get_bus(&soc->i2c, 9), TYPE_TMP105,
                      0x4a);
 
     /* The witherspoon board expects Epson RX8900 I2C RTC but a ds1338 is
      * good enough */
-    i2c_create_slave(aspeed_i2c_get_bus(DEVICE(&soc->i2c), 11), "ds1338", 0x32);
+    i2c_slave_create_simple(aspeed_i2c_get_bus(&soc->i2c, 11), "ds1338", 0x32);
 
-    smbus_eeprom_init_one(aspeed_i2c_get_bus(DEVICE(&soc->i2c), 11), 0x51,
+    smbus_eeprom_init_one(aspeed_i2c_get_bus(&soc->i2c, 11), 0x51,
                           eeprom_buf);
-    dev = i2c_try_create_slave(TYPE_PCA9552, 0x60);
+    dev = DEVICE(i2c_slave_new(TYPE_PCA9552, 0x60));
     qdev_prop_set_string(dev, "description", "pca0");
-    i2c_realize_and_unref(dev, aspeed_i2c_get_bus(DEVICE(&soc->i2c), 11),
-                          &error_fatal);
+    i2c_slave_realize_and_unref(I2C_SLAVE(dev),
+                                aspeed_i2c_get_bus(&soc->i2c, 11),
+                                &error_fatal);
     /* Bus 11: TODO ucd90160@64 */
 }
 
diff --git a/hw/arm/musicpal.c b/hw/arm/musicpal.c
index ff9a7c8cc6..c3b9780f35 100644
--- a/hw/arm/musicpal.c
+++ b/hw/arm/musicpal.c
@@ -1584,7 +1584,7 @@ static void musicpal_init(MachineState *machine)
     DeviceState *i2c_dev;
     DeviceState *lcd_dev;
     DeviceState *key_dev;
-    DeviceState *wm8750_dev;
+    I2CSlave *wm8750_dev;
     SysBusDevice *s;
     I2CBus *i2c;
     int i;
@@ -1687,7 +1687,7 @@ static void musicpal_init(MachineState *machine)
         qdev_connect_gpio_out(key_dev, i, qdev_get_gpio_in(dev, i + 15));
     }
 
-    wm8750_dev = i2c_create_slave(i2c, TYPE_WM8750, MP_WM_ADDR);
+    wm8750_dev = i2c_slave_create_simple(i2c, TYPE_WM8750, MP_WM_ADDR);
     dev = qdev_new(TYPE_MV88W8618_AUDIO);
     s = SYS_BUS_DEVICE(dev);
     object_property_set_link(OBJECT(dev), "wm8750", OBJECT(wm8750_dev),
diff --git a/hw/arm/nseries.c b/hw/arm/nseries.c
index 428a2a2c5a..e48092ca04 100644
--- a/hw/arm/nseries.c
+++ b/hw/arm/nseries.c
@@ -215,7 +215,7 @@ static void n8x0_i2c_setup(struct n800_s *s)
     I2CBus *i2c = omap_i2c_bus(s->mpu->i2c[0]);
 
     /* Attach a menelaus PM chip */
-    dev = i2c_create_slave(i2c, "twl92230", N8X0_MENELAUS_ADDR);
+    dev = DEVICE(i2c_slave_create_simple(i2c, "twl92230", N8X0_MENELAUS_ADDR));
     qdev_connect_gpio_out(dev, 3,
                           qdev_get_gpio_in(s->mpu->ih[0],
                                            OMAP_INT_24XX_SYS_NIRQ));
@@ -224,7 +224,7 @@ static void n8x0_i2c_setup(struct n800_s *s)
     qemu_register_powerdown_notifier(&n8x0_system_powerdown_notifier);
 
     /* Attach a TMP105 PM chip (A0 wired to ground) */
-    dev = i2c_create_slave(i2c, TYPE_TMP105, N8X0_TMP105_ADDR);
+    dev = DEVICE(i2c_slave_create_simple(i2c, TYPE_TMP105, N8X0_TMP105_ADDR));
     qdev_connect_gpio_out(dev, 0, tmp_irq);
 }
 
@@ -416,8 +416,8 @@ static void n810_kbd_setup(struct n800_s *s)
 
     /* Attach the LM8322 keyboard to the I2C bus,
      * should happen in n8x0_i2c_setup and s->kbd be initialised here.  */
-    s->kbd = i2c_create_slave(omap_i2c_bus(s->mpu->i2c[0]),
-                           "lm8323", N810_LM8323_ADDR);
+    s->kbd = DEVICE(i2c_slave_create_simple(omap_i2c_bus(s->mpu->i2c[0]),
+                                            "lm8323", N810_LM8323_ADDR));
     qdev_connect_gpio_out(s->kbd, 0, kbd_irq);
 }
 
diff --git a/hw/arm/pxa2xx.c b/hw/arm/pxa2xx.c
index f104a33463..6203c4cfe0 100644
--- a/hw/arm/pxa2xx.c
+++ b/hw/arm/pxa2xx.c
@@ -1522,8 +1522,9 @@ PXA2xxI2CState *pxa2xx_i2c_init(hwaddr base,
     s = PXA2XX_I2C(i2c_dev);
     /* FIXME: Should the slave device really be on a separate bus?  */
     i2cbus = i2c_init_bus(dev, "dummy");
-    dev = i2c_create_slave(i2cbus, TYPE_PXA2XX_I2C_SLAVE, 0);
-    s->slave = PXA2XX_I2C_SLAVE(dev);
+    s->slave = PXA2XX_I2C_SLAVE(i2c_slave_create_simple(i2cbus,
+                                                        TYPE_PXA2XX_I2C_SLAVE,
+                                                        0));
     s->slave->host = s;
 
     return s;
diff --git a/hw/arm/realview.c b/hw/arm/realview.c
index 22e132058e..c1ff172b13 100644
--- a/hw/arm/realview.c
+++ b/hw/arm/realview.c
@@ -285,7 +285,7 @@ static void realview_init(MachineState *machine,
 
     dev = sysbus_create_simple(TYPE_VERSATILE_I2C, 0x10002000, NULL);
     i2c = (I2CBus *)qdev_get_child_bus(dev, "i2c");
-    i2c_create_slave(i2c, "ds1338", 0x68);
+    i2c_slave_create_simple(i2c, "ds1338", 0x68);
 
     /* Memory map for RealView Emulation Baseboard:  */
     /* 0x10000000 System registers.  */
diff --git a/hw/arm/spitz.c b/hw/arm/spitz.c
index f020aff974..7ac8254aa6 100644
--- a/hw/arm/spitz.c
+++ b/hw/arm/spitz.c
@@ -787,7 +787,7 @@ static void spitz_i2c_setup(PXA2xxState *cpu)
     DeviceState *wm;
 
     /* Attach a WM8750 to the bus */
-    wm = i2c_create_slave(bus, TYPE_WM8750, 0);
+    wm = DEVICE(i2c_slave_create_simple(bus, TYPE_WM8750, 0));
 
     spitz_wm8750_addr(wm, 0, 0);
     qdev_connect_gpio_out(cpu->gpio, SPITZ_GPIO_WM,
@@ -802,7 +802,7 @@ static void spitz_i2c_setup(PXA2xxState *cpu)
 static void spitz_akita_i2c_setup(PXA2xxState *cpu)
 {
     /* Attach a Max7310 to Akita I2C bus.  */
-    i2c_create_slave(pxa2xx_i2c_bus(cpu->i2c[0]), "max7310",
+    i2c_slave_create_simple(pxa2xx_i2c_bus(cpu->i2c[0]), "max7310",
                      AKITA_MAX_ADDR);
 }
 
diff --git a/hw/arm/stellaris.c b/hw/arm/stellaris.c
index 7156fb3ece..28eb15c76c 100644
--- a/hw/arm/stellaris.c
+++ b/hw/arm/stellaris.c
@@ -1380,7 +1380,7 @@ static void stellaris_init(MachineState *ms, stellaris_board_info *board)
                                    qdev_get_gpio_in(nvic, 8));
         i2c = (I2CBus *)qdev_get_child_bus(dev, "i2c");
         if (board->peripherals & BP_OLED_I2C) {
-            i2c_create_slave(i2c, "ssd0303", 0x3d);
+            i2c_slave_create_simple(i2c, "ssd0303", 0x3d);
         }
     }
 
diff --git a/hw/arm/tosa.c b/hw/arm/tosa.c
index 383b3b22e2..e29566f7b3 100644
--- a/hw/arm/tosa.c
+++ b/hw/arm/tosa.c
@@ -234,7 +234,7 @@ static uint8_t tosa_dac_recv(I2CSlave *s)
 static void tosa_tg_init(PXA2xxState *cpu)
 {
     I2CBus *bus = pxa2xx_i2c_bus(cpu->i2c[0]);
-    i2c_create_slave(bus, TYPE_TOSA_DAC, DAC_BASE);
+    i2c_slave_create_simple(bus, TYPE_TOSA_DAC, DAC_BASE);
     ssi_create_slave(cpu->ssp[1], "tosa-ssp");
 }
 
diff --git a/hw/arm/versatilepb.c b/hw/arm/versatilepb.c
index d09ea24ae2..9dc93182b6 100644
--- a/hw/arm/versatilepb.c
+++ b/hw/arm/versatilepb.c
@@ -317,7 +317,7 @@ static void versatile_init(MachineState *machine, int board_id)
 
     dev = sysbus_create_simple(TYPE_VERSATILE_I2C, 0x10002000, NULL);
     i2c = (I2CBus *)qdev_get_child_bus(dev, "i2c");
-    i2c_create_slave(i2c, "ds1338", 0x68);
+    i2c_slave_create_simple(i2c, "ds1338", 0x68);
 
     /* Add PL041 AACI Interface to the LM4549 codec */
     pl041 = qdev_new("pl041");
diff --git a/hw/arm/vexpress.c b/hw/arm/vexpress.c
index 762b068e90..1dc971c34f 100644
--- a/hw/arm/vexpress.c
+++ b/hw/arm/vexpress.c
@@ -642,7 +642,7 @@ static void vexpress_common_init(MachineState *machine)
 
     dev = sysbus_create_simple(TYPE_VERSATILE_I2C, map[VE_SERIALDVI], NULL);
     i2c = (I2CBus *)qdev_get_child_bus(dev, "i2c");
-    i2c_create_slave(i2c, "sii9022", 0x39);
+    i2c_slave_create_simple(i2c, "sii9022", 0x39);
 
     sysbus_create_simple("pl031", map[VE_RTC], pic[4]); /* RTC */
 
diff --git a/hw/arm/z2.c b/hw/arm/z2.c
index e1f22f5868..9a9bbc653b 100644
--- a/hw/arm/z2.c
+++ b/hw/arm/z2.c
@@ -330,8 +330,8 @@ static void z2_init(MachineState *machine)
     type_register_static(&aer915_info);
     z2_lcd = ssi_create_slave(mpu->ssp[1], TYPE_ZIPIT_LCD);
     bus = pxa2xx_i2c_bus(mpu->i2c[0]);
-    i2c_create_slave(bus, TYPE_AER915, 0x55);
-    wm = i2c_create_slave(bus, TYPE_WM8750, 0x1b);
+    i2c_slave_create_simple(bus, TYPE_AER915, 0x55);
+    wm = DEVICE(i2c_slave_create_simple(bus, TYPE_WM8750, 0x1b));
     mpu->i2s->opaque = wm;
     mpu->i2s->codec_out = wm8750_dac_dat;
     mpu->i2s->codec_in = wm8750_adc_dat;
diff --git a/hw/display/sii9022.c b/hw/display/sii9022.c
index 0710ce9de5..3b82a8567f 100644
--- a/hw/display/sii9022.c
+++ b/hw/display/sii9022.c
@@ -161,7 +161,7 @@ static void sii9022_realize(DeviceState *dev, Error **errp)
     I2CBus *bus;
 
     bus = I2C_BUS(qdev_get_parent_bus(dev));
-    i2c_create_slave(bus, TYPE_I2CDDC, 0x50);
+    i2c_slave_create_simple(bus, TYPE_I2CDDC, 0x50);
 }
 
 static void sii9022_class_init(ObjectClass *klass, void *data)
diff --git a/hw/i2c/Kconfig b/hw/i2c/Kconfig
index 2bbd395813..09642a6dcb 100644
--- a/hw/i2c/Kconfig
+++ b/hw/i2c/Kconfig
@@ -1,9 +1,13 @@
 config I2C
     bool
 
+config SMBUS
+    bool
+    select I2C
+
 config SMBUS_EEPROM
     bool
-    depends on I2C
+    select SMBUS
 
 config VERSATILE_I2C
     bool
@@ -11,7 +15,7 @@ config VERSATILE_I2C
 
 config ACPI_SMBUS
     bool
-    select I2C
+    select SMBUS
 
 config BITBANG_I2C
     bool
diff --git a/hw/i2c/Makefile.objs b/hw/i2c/Makefile.objs
index 6ba976b257..f2c61eaa8b 100644
--- a/hw/i2c/Makefile.objs
+++ b/hw/i2c/Makefile.objs
@@ -1,4 +1,5 @@
-common-obj-$(CONFIG_I2C) += core.o smbus_slave.o smbus_master.o
+common-obj-$(CONFIG_I2C) += core.o
+common-obj-$(CONFIG_SMBUS) += smbus_slave.o smbus_master.o
 common-obj-$(CONFIG_SMBUS_EEPROM) += smbus_eeprom.o
 common-obj-$(CONFIG_VERSATILE_I2C) += versatile_i2c.o
 common-obj-$(CONFIG_ACPI_X86_ICH) += smbus_ich9.o
diff --git a/hw/i2c/aspeed_i2c.c b/hw/i2c/aspeed_i2c.c
index fb973a983d..518a3f5c6f 100644
--- a/hw/i2c/aspeed_i2c.c
+++ b/hw/i2c/aspeed_i2c.c
@@ -959,9 +959,8 @@ static void aspeed_i2c_register_types(void)
 type_init(aspeed_i2c_register_types)
 
 
-I2CBus *aspeed_i2c_get_bus(DeviceState *dev, int busnr)
+I2CBus *aspeed_i2c_get_bus(AspeedI2CState *s, int busnr)
 {
-    AspeedI2CState *s = ASPEED_I2C(dev);
     AspeedI2CClass *aic = ASPEED_I2C_GET_CLASS(s);
     I2CBus *bus = NULL;
 
diff --git a/hw/i2c/core.c b/hw/i2c/core.c
index acf34a12d6..21ec52ac5a 100644
--- a/hw/i2c/core.c
+++ b/hw/i2c/core.c
@@ -267,26 +267,25 @@ const VMStateDescription vmstate_i2c_slave = {
     }
 };
 
-DeviceState *i2c_try_create_slave(const char *name, uint8_t addr)
+I2CSlave *i2c_slave_new(const char *name, uint8_t addr)
 {
     DeviceState *dev;
 
     dev = qdev_new(name);
     qdev_prop_set_uint8(dev, "address", addr);
-    return dev;
+    return I2C_SLAVE(dev);
 }
 
-bool i2c_realize_and_unref(DeviceState *dev, I2CBus *bus, Error **errp)
+bool i2c_slave_realize_and_unref(I2CSlave *dev, I2CBus *bus, Error **errp)
 {
-    return qdev_realize_and_unref(dev, &bus->qbus, errp);
+    return qdev_realize_and_unref(&dev->qdev, &bus->qbus, errp);
 }
 
-DeviceState *i2c_create_slave(I2CBus *bus, const char *name, uint8_t addr)
+I2CSlave *i2c_slave_create_simple(I2CBus *bus, const char *name, uint8_t addr)
 {
-    DeviceState *dev;
+    I2CSlave *dev = i2c_slave_new(name, addr);
 
-    dev = i2c_try_create_slave(name, addr);
-    i2c_realize_and_unref(dev, bus, &error_fatal);
+    i2c_slave_realize_and_unref(dev, bus, &error_abort);
 
     return dev;
 }
diff --git a/hw/ppc/e500.c b/hw/ppc/e500.c
index 5448d101d9..ab9884e315 100644
--- a/hw/ppc/e500.c
+++ b/hw/ppc/e500.c
@@ -941,7 +941,7 @@ void ppce500_init(MachineState *machine)
     memory_region_add_subregion(ccsr_addr_space, MPC8544_I2C_REGS_OFFSET,
                                 sysbus_mmio_get_region(s, 0));
     i2c = (I2CBus *)qdev_get_child_bus(dev, "i2c");
-    i2c_create_slave(i2c, "ds1338", RTC_REGS_OFFSET);
+    i2c_slave_create_simple(i2c, "ds1338", RTC_REGS_OFFSET);
 
 
     /* General Utility device */
diff --git a/hw/ppc/sam460ex.c b/hw/ppc/sam460ex.c
index 1a106a68de..1702344c46 100644
--- a/hw/ppc/sam460ex.c
+++ b/hw/ppc/sam460ex.c
@@ -339,7 +339,7 @@ static void sam460ex_init(MachineState *machine)
     spd_data[20] = 4; /* SO-DIMM module */
     smbus_eeprom_init_one(i2c, 0x50, spd_data);
     /* RTC */
-    i2c_create_slave(i2c, "m41t80", 0x68);
+    i2c_slave_create_simple(i2c, "m41t80", 0x68);
 
     dev = sysbus_create_simple(TYPE_PPC4xx_I2C, 0x4ef600800, uic[0][3]);
 
diff --git a/include/hw/i2c/aspeed_i2c.h b/include/hw/i2c/aspeed_i2c.h
index f1b9e5bf91..243789ae5d 100644
--- a/include/hw/i2c/aspeed_i2c.h
+++ b/include/hw/i2c/aspeed_i2c.h
@@ -93,6 +93,6 @@ typedef struct AspeedI2CClass {
 
 } AspeedI2CClass;
 
-I2CBus *aspeed_i2c_get_bus(DeviceState *dev, int busnr);
+I2CBus *aspeed_i2c_get_bus(AspeedI2CState *s, int busnr);
 
 #endif /* ASPEED_I2C_H */
diff --git a/include/hw/i2c/i2c.h b/include/hw/i2c/i2c.h
index d6e3d85faf..a9c030a512 100644
--- a/include/hw/i2c/i2c.h
+++ b/include/hw/i2c/i2c.h
@@ -79,9 +79,57 @@ int i2c_send_recv(I2CBus *bus, uint8_t *data, bool send);
 int i2c_send(I2CBus *bus, uint8_t data);
 uint8_t i2c_recv(I2CBus *bus);
 
-DeviceState *i2c_create_slave(I2CBus *bus, const char *name, uint8_t addr);
-DeviceState *i2c_try_create_slave(const char *name, uint8_t addr);
-bool i2c_realize_and_unref(DeviceState *dev, I2CBus *bus, Error **errp);
+/**
+ * Create an I2C slave device on the heap.
+ * @name: a device type name
+ * @addr: I2C address of the slave when put on a bus
+ *
+ * This only initializes the device state structure and allows
+ * properties to be set. Type @name must exist. The device still
+ * needs to be realized. See qdev-core.h.
+ */
+I2CSlave *i2c_slave_new(const char *name, uint8_t addr);
+
+/**
+ * Create and realize an I2C slave device on the heap.
+ * @bus: I2C bus to put it on
+ * @name: I2C slave device type name
+ * @addr: I2C address of the slave when put on a bus
+ *
+ * Create the device state structure, initialize it, put it on the
+ * specified @bus, and drop the reference to it (the device is realized).
+ */
+I2CSlave *i2c_slave_create_simple(I2CBus *bus, const char *name, uint8_t addr);
+
+/**
+ * Realize and and drop a reference an I2C slave device
+ * @dev: I2C slave device to realize
+ * @bus: I2C bus to put it on
+ * @addr: I2C address of the slave on the bus
+ * @errp: pointer to NULL initialized error object
+ *
+ * Returns: %true on success, %false on failure.
+ *
+ * Call 'realize' on @dev, put it on the specified @bus, and drop the
+ * reference to it.
+ *
+ * This function is useful if you have created @dev via qdev_new(),
+ * i2c_slave_new() or i2c_slave_try_new() (which take a reference to
+ * the device it returns to you), so that you can set properties on it
+ * before realizing it. If you don't need to set properties then
+ * i2c_slave_create_simple() is probably better (as it does the create,
+ * init and realize in one step).
+ *
+ * If you are embedding the I2C slave into another QOM device and
+ * initialized it via some variant on object_initialize_child() then
+ * do not use this function, because that family of functions arrange
+ * for the only reference to the child device to be held by the parent
+ * via the child<> property, and so the reference-count-drop done here
+ * would be incorrect.  (Instead you would want i2c_slave_realize(),
+ * which doesn't currently exist but would be trivial to create if we
+ * had any code that wanted it.)
+ */
+bool i2c_slave_realize_and_unref(I2CSlave *dev, I2CBus *bus, Error **errp);
 
 /* lm832x.c */
 void lm832x_key_event(DeviceState *dev, int key, int state);