libqos: convert I2C to qgraph

Create an i2c-bus interface, corresponding to the I2CAdapter struct.
Wrap IMXI2C and OMAPI2C with a QOSGraphObject, and add the get_driver
function to retrieve the I2CAdapter.

The conversion is still not complete; for simplicity, i2c_recv and
i2c_send (along with their wrappers) still take an adapter/address
pair.  Fixing that would be complicated until the tests are converted
to qgraph, so it is left for after the conversion.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

tests/Makefile.include

@@ -694,6 +694,8 @@ libqos-usb-obj-y = $(libqos-spapr-obj-y) $(libqos-pc-obj-y) tests/libqos/usb.o
 qos-test-obj-y = tests/qos-test.o $(libqgraph-obj-y)
 qos-test-obj-y += $(libqos-pc-obj-y) $(libqos-spapr-obj-y)
 qos-test-obj-y += tests/libqos/e1000e.o
+qos-test-obj-y += $(libqos-imx-obj-y)
+qos-test-obj-y += $(libqos-omap-obj-y)
 qos-test-obj-y += tests/libqos/sdhci.o
 qos-test-obj-y += tests/libqos/tpci200.o
 qos-test-obj-y += tests/libqos/virtio.o

tests/libqos/i2c-imx.c

@@ -186,10 +186,22 @@ static void imx_i2c_recv(I2CAdapter *i2c, uint8_t addr,
     g_assert((status & I2SR_IBB) == 0);
 }
 
+static void *imx_i2c_get_driver(void *obj, const char *interface)
+{
+    IMXI2C *s = obj;
+    if (!g_strcmp0(interface, "i2c-bus")) {
+        return &s->parent;
+    }
+    fprintf(stderr, "%s not present in imx-i2c\n", interface);
+    g_assert_not_reached();
+}
+
 void imx_i2c_init(IMXI2C *s, QTestState *qts, uint64_t addr)
 {
     s->addr = addr;
 
+    s->obj.get_driver = imx_i2c_get_driver;
+
     s->parent.send = imx_i2c_send;
     s->parent.recv = imx_i2c_recv;
     s->parent.qts = qts;
@@ -213,3 +225,11 @@ void imx_i2c_free(I2CAdapter *i2c)
     s = container_of(i2c, IMXI2C, parent);
     g_free(s);
 }
+
+static void imx_i2c_register_nodes(void)
+{
+    qos_node_create_driver("imx.i2c", NULL);
+    qos_node_produces("imx.i2c", "i2c-bus");
+}
+
+libqos_init(imx_i2c_register_nodes);

tests/libqos/i2c-omap.c

@@ -155,20 +155,36 @@ static void omap_i2c_recv(I2CAdapter *i2c, uint8_t addr,
     g_assert((data & OMAP_I2C_CON_STP) == 0);
 }
 
-void omap_i2c_init(OMAPI2C *s, QTestState *qts, uint64_t addr)
+static void *omap_i2c_get_driver(void *obj, const char *interface)
+{
+    OMAPI2C *s = obj;
+    if (!g_strcmp0(interface, "i2c-bus")) {
+        return &s->parent;
+    }
+    fprintf(stderr, "%s not present in omap_i2c\n", interface);
+    g_assert_not_reached();
+}
+
+static void omap_i2c_start_hw(QOSGraphObject *object)
 {
-    I2CAdapter *i2c = (I2CAdapter *)s;
+    OMAPI2C *s = (OMAPI2C *) object;
     uint16_t data;
 
+    /* verify the mmio address by looking for a known signature */
+    data = qtest_readw(s->parent.qts, s->addr + OMAP_I2C_REV);
+    g_assert_cmphex(data, ==, 0x34);
+}
+
+void omap_i2c_init(OMAPI2C *s, QTestState *qts, uint64_t addr)
+{
     s->addr = addr;
 
-    i2c->send = omap_i2c_send;
-    i2c->recv = omap_i2c_recv;
-    i2c->qts = qts;
+    s->obj.get_driver = omap_i2c_get_driver;
+    s->obj.start_hw = omap_i2c_start_hw;
 
-    /* verify the mmio address by looking for a known signature */
-    data = qtest_readw(qts, addr + OMAP_I2C_REV);
-    g_assert_cmphex(data, ==, 0x34);
+    s->parent.send = omap_i2c_send;
+    s->parent.recv = omap_i2c_recv;
+    s->parent.qts = qts;
 }
 
 I2CAdapter *omap_i2c_create(QTestState *qts, uint64_t addr)
@@ -189,3 +205,11 @@ void omap_i2c_free(I2CAdapter *i2c)
     s = container_of(i2c, OMAPI2C, parent);
     g_free(s);
 }
+
+static void omap_i2c_register_nodes(void)
+{
+    qos_node_create_driver("omap_i2c", NULL);
+    qos_node_produces("omap_i2c", "i2c-bus");
+}
+
+libqos_init(omap_i2c_register_nodes);

tests/libqos/i2c.c

@@ -68,3 +68,11 @@ void i2c_set16(I2CAdapter *i2c, uint8_t addr, uint8_t reg,
     data[1] = value & 255;
     i2c_write_block(i2c, addr, reg, data, sizeof(data));
 }
+
+void *i2c_device_create(void *i2c_bus, QGuestAllocator *alloc, void *addr)
+{
+    QI2CDevice *i2cdev = g_new0(QI2CDevice, 1);
+
+    i2cdev->bus = i2c_bus;
+    return &i2cdev->obj;
+}

tests/libqos/i2c.h

@@ -10,6 +10,7 @@
 #define LIBQOS_I2C_H
 
 #include "libqtest.h"
+#include "libqos/qgraph.h"
 
 typedef struct I2CAdapter I2CAdapter;
 struct I2CAdapter {
@@ -21,8 +22,26 @@ struct I2CAdapter {
     QTestState *qts;
 };
 
+typedef struct QI2CDevice QI2CDevice;
+struct QI2CDevice {
+    /*
+     * For now, all devices are simple enough that there is no need for
+     * them to define their own constructor and get_driver functions.
+     * Therefore, QOSGraphObject is included directly in QI2CDevice;
+     * the tests expect to get a QI2CDevice rather than doing something
+     * like obj->get_driver("i2c-device").
+     *
+     * In fact there is no i2c-device interface even, because there are
+     * no generic I2C tests).
+     */
+    QOSGraphObject obj;
+    I2CAdapter *bus;
+};
+
 #define OMAP2_I2C_1_BASE 0x48070000
 
+void *i2c_device_create(void *i2c_bus, QGuestAllocator *alloc, void *addr);
+
 void i2c_send(I2CAdapter *i2c, uint8_t addr,
               const uint8_t *buf, uint16_t len);
 void i2c_recv(I2CAdapter *i2c, uint8_t addr,
@@ -41,6 +60,7 @@ void i2c_set16(I2CAdapter *i2c, uint8_t addr, uint8_t reg,
 
 /* i2c-omap.c */
 typedef struct OMAPI2C {
+    QOSGraphObject obj;
     I2CAdapter parent;
 
     uint64_t addr;
@@ -52,6 +72,7 @@ void omap_i2c_free(I2CAdapter *i2c);
 
 /* i2c-imx.c */
 typedef struct IMXI2C {
+    QOSGraphObject obj;
     I2CAdapter parent;
 
     uint64_t addr;