diff --git a/tests/ds1338-test.c b/tests/ds1338-test.c
index 26968bc..742dad9 100644
--- a/tests/ds1338-test.c
+++ b/tests/ds1338-test.c
@@ -61,16 +61,14 @@ int main(int argc, char **argv)
     g_test_init(&argc, &argv, NULL);
 
     s = qtest_start("-display none -machine imx25-pdk");
-    i2c = imx_i2c_create(IMX25_I2C_0_BASE);
+    i2c = imx_i2c_create(s, IMX25_I2C_0_BASE);
     addr = DS1338_ADDR;
 
     qtest_add_func("/ds1338/tx-rx", send_and_receive);
 
     ret = g_test_run();
 
-    if (s) {
-        qtest_quit(s);
-    }
+    qtest_quit(s);
     g_free(i2c);
 
     return ret;
diff --git a/tests/libqos/i2c-imx.c b/tests/libqos/i2c-imx.c
index 1c4b431..0945f2e 100644
--- a/tests/libqos/i2c-imx.c
+++ b/tests/libqos/i2c-imx.c
@@ -40,8 +40,8 @@ typedef struct IMXI2C {
 static void imx_i2c_set_slave_addr(IMXI2C *s, uint8_t addr,
                                    enum IMXI2CDirection direction)
 {
-    writeb(s->addr + I2DR_ADDR, (addr << 1) |
-           (direction == IMX_I2C_READ ? 1 : 0));
+    qtest_writeb(s->parent.qts, s->addr + I2DR_ADDR,
+                 (addr << 1) | (direction == IMX_I2C_READ ? 1 : 0));
 }
 
 static void imx_i2c_send(I2CAdapter *i2c, uint8_t addr,
@@ -63,35 +63,35 @@ static void imx_i2c_send(I2CAdapter *i2c, uint8_t addr,
            I2CR_MTX |
            I2CR_TXAK;
 
-    writeb(s->addr + I2CR_ADDR, data);
-    status = readb(s->addr + I2SR_ADDR);
+    qtest_writeb(i2c->qts, s->addr + I2CR_ADDR, data);
+    status = qtest_readb(i2c->qts, s->addr + I2SR_ADDR);
     g_assert((status & I2SR_IBB) != 0);
 
     /* set the slave address */
     imx_i2c_set_slave_addr(s, addr, IMX_I2C_WRITE);
-    status = readb(s->addr + I2SR_ADDR);
+    status = qtest_readb(i2c->qts, s->addr + I2SR_ADDR);
     g_assert((status & I2SR_IIF) != 0);
     g_assert((status & I2SR_RXAK) == 0);
 
     /* ack the interrupt */
-    writeb(s->addr + I2SR_ADDR, 0);
-    status = readb(s->addr + I2SR_ADDR);
+    qtest_writeb(i2c->qts, s->addr + I2SR_ADDR, 0);
+    status = qtest_readb(i2c->qts, s->addr + I2SR_ADDR);
     g_assert((status & I2SR_IIF) == 0);
 
     while (size < len) {
         /* check we are still busy */
-        status = readb(s->addr + I2SR_ADDR);
+        status = qtest_readb(i2c->qts, s->addr + I2SR_ADDR);
         g_assert((status & I2SR_IBB) != 0);
 
         /* write the data */
-        writeb(s->addr + I2DR_ADDR, buf[size]);
-        status = readb(s->addr + I2SR_ADDR);
+        qtest_writeb(i2c->qts, s->addr + I2DR_ADDR, buf[size]);
+        status = qtest_readb(i2c->qts, s->addr + I2SR_ADDR);
         g_assert((status & I2SR_IIF) != 0);
         g_assert((status & I2SR_RXAK) == 0);
 
         /* ack the interrupt */
-        writeb(s->addr + I2SR_ADDR, 0);
-        status = readb(s->addr + I2SR_ADDR);
+        qtest_writeb(i2c->qts, s->addr + I2SR_ADDR, 0);
+        status = qtest_readb(i2c->qts, s->addr + I2SR_ADDR);
         g_assert((status & I2SR_IIF) == 0);
 
         size++;
@@ -99,8 +99,8 @@ static void imx_i2c_send(I2CAdapter *i2c, uint8_t addr,
 
     /* release the bus */
     data &= ~(I2CR_MSTA | I2CR_MTX);
-    writeb(s->addr + I2CR_ADDR, data);
-    status = readb(s->addr + I2SR_ADDR);
+    qtest_writeb(i2c->qts, s->addr + I2CR_ADDR, data);
+    status = qtest_readb(i2c->qts, s->addr + I2SR_ADDR);
     g_assert((status & I2SR_IBB) == 0);
 }
 
@@ -123,19 +123,19 @@ static void imx_i2c_recv(I2CAdapter *i2c, uint8_t addr,
            I2CR_MTX |
            I2CR_TXAK;
 
-    writeb(s->addr + I2CR_ADDR, data);
-    status = readb(s->addr + I2SR_ADDR);
+    qtest_writeb(i2c->qts, s->addr + I2CR_ADDR, data);
+    status = qtest_readb(i2c->qts, s->addr + I2SR_ADDR);
     g_assert((status & I2SR_IBB) != 0);
 
     /* set the slave address */
     imx_i2c_set_slave_addr(s, addr, IMX_I2C_READ);
-    status = readb(s->addr + I2SR_ADDR);
+    status = qtest_readb(i2c->qts, s->addr + I2SR_ADDR);
     g_assert((status & I2SR_IIF) != 0);
     g_assert((status & I2SR_RXAK) == 0);
 
     /* ack the interrupt */
-    writeb(s->addr + I2SR_ADDR, 0);
-    status = readb(s->addr + I2SR_ADDR);
+    qtest_writeb(i2c->qts, s->addr + I2SR_ADDR, 0);
+    status = qtest_readb(i2c->qts, s->addr + I2SR_ADDR);
     g_assert((status & I2SR_IIF) == 0);
 
     /* set the bus for read */
@@ -144,23 +144,23 @@ static void imx_i2c_recv(I2CAdapter *i2c, uint8_t addr,
     if (len != 1) {
         data &= ~I2CR_TXAK;
     }
-    writeb(s->addr + I2CR_ADDR, data);
-    status = readb(s->addr + I2SR_ADDR);
+    qtest_writeb(i2c->qts, s->addr + I2CR_ADDR, data);
+    status = qtest_readb(i2c->qts, s->addr + I2SR_ADDR);
     g_assert((status & I2SR_IBB) != 0);
 
     /* dummy read */
-    readb(s->addr + I2DR_ADDR);
-    status = readb(s->addr + I2SR_ADDR);
+    qtest_readb(i2c->qts, s->addr + I2DR_ADDR);
+    status = qtest_readb(i2c->qts, s->addr + I2SR_ADDR);
     g_assert((status & I2SR_IIF) != 0);
 
     /* ack the interrupt */
-    writeb(s->addr + I2SR_ADDR, 0);
-    status = readb(s->addr + I2SR_ADDR);
+    qtest_writeb(i2c->qts, s->addr + I2SR_ADDR, 0);
+    status = qtest_readb(i2c->qts, s->addr + I2SR_ADDR);
     g_assert((status & I2SR_IIF) == 0);
 
     while (size < len) {
         /* check we are still busy */
-        status = readb(s->addr + I2SR_ADDR);
+        status = qtest_readb(i2c->qts, s->addr + I2SR_ADDR);
         g_assert((status & I2SR_IBB) != 0);
 
         if (size == (len - 1)) {
@@ -170,30 +170,30 @@ static void imx_i2c_recv(I2CAdapter *i2c, uint8_t addr,
             /* ack the data read */
             data |= I2CR_TXAK;
         }
-        writeb(s->addr + I2CR_ADDR, data);
+        qtest_writeb(i2c->qts, s->addr + I2CR_ADDR, data);
 
         /* read the data */
-        buf[size] = readb(s->addr + I2DR_ADDR);
+        buf[size] = qtest_readb(i2c->qts, s->addr + I2DR_ADDR);
 
         if (size != (len - 1)) {
-            status = readb(s->addr + I2SR_ADDR);
+            status = qtest_readb(i2c->qts, s->addr + I2SR_ADDR);
             g_assert((status & I2SR_IIF) != 0);
 
             /* ack the interrupt */
-            writeb(s->addr + I2SR_ADDR, 0);
+            qtest_writeb(i2c->qts, s->addr + I2SR_ADDR, 0);
         }
 
-        status = readb(s->addr + I2SR_ADDR);
+        status = qtest_readb(i2c->qts, s->addr + I2SR_ADDR);
         g_assert((status & I2SR_IIF) == 0);
 
         size++;
     }
 
-    status = readb(s->addr + I2SR_ADDR);
+    status = qtest_readb(i2c->qts, s->addr + I2SR_ADDR);
     g_assert((status & I2SR_IBB) == 0);
 }
 
-I2CAdapter *imx_i2c_create(uint64_t addr)
+I2CAdapter *imx_i2c_create(QTestState *qts, uint64_t addr)
 {
     IMXI2C *s = g_malloc0(sizeof(*s));
     I2CAdapter *i2c = (I2CAdapter *)s;
@@ -202,6 +202,7 @@ I2CAdapter *imx_i2c_create(uint64_t addr)
 
     i2c->send = imx_i2c_send;
     i2c->recv = imx_i2c_recv;
+    i2c->qts = qts;
 
     return i2c;
 }
diff --git a/tests/libqos/i2c-omap.c b/tests/libqos/i2c-omap.c
index f603fdf..1ef6e7b 100644
--- a/tests/libqos/i2c-omap.c
+++ b/tests/libqos/i2c-omap.c
@@ -51,8 +51,8 @@ static void omap_i2c_set_slave_addr(OMAPI2C *s, uint8_t addr)
 {
     uint16_t data = addr;
 
-    writew(s->addr + OMAP_I2C_SA, data);
-    data = readw(s->addr + OMAP_I2C_SA);
+    qtest_writew(s->parent.qts, s->addr + OMAP_I2C_SA, data);
+    data = qtest_readw(s->parent.qts, s->addr + OMAP_I2C_SA);
     g_assert_cmphex(data, ==, addr);
 }
 
@@ -65,38 +65,38 @@ static void omap_i2c_send(I2CAdapter *i2c, uint8_t addr,
     omap_i2c_set_slave_addr(s, addr);
 
     data = len;
-    writew(s->addr + OMAP_I2C_CNT, data);
+    qtest_writew(i2c->qts, s->addr + OMAP_I2C_CNT, data);
 
     data = OMAP_I2C_CON_I2C_EN |
            OMAP_I2C_CON_TRX |
            OMAP_I2C_CON_MST |
            OMAP_I2C_CON_STT |
            OMAP_I2C_CON_STP;
-    writew(s->addr + OMAP_I2C_CON, data);
-    data = readw(s->addr + OMAP_I2C_CON);
+    qtest_writew(i2c->qts, s->addr + OMAP_I2C_CON, data);
+    data = qtest_readw(i2c->qts, s->addr + OMAP_I2C_CON);
     g_assert((data & OMAP_I2C_CON_STP) != 0);
 
-    data = readw(s->addr + OMAP_I2C_STAT);
+    data = qtest_readw(i2c->qts, s->addr + OMAP_I2C_STAT);
     g_assert((data & OMAP_I2C_STAT_NACK) == 0);
 
     while (len > 1) {
-        data = readw(s->addr + OMAP_I2C_STAT);
+        data = qtest_readw(i2c->qts, s->addr + OMAP_I2C_STAT);
         g_assert((data & OMAP_I2C_STAT_XRDY) != 0);
 
         data = buf[0] | ((uint16_t)buf[1] << 8);
-        writew(s->addr + OMAP_I2C_DATA, data);
+        qtest_writew(i2c->qts, s->addr + OMAP_I2C_DATA, data);
         buf = (uint8_t *)buf + 2;
         len -= 2;
     }
     if (len == 1) {
-        data = readw(s->addr + OMAP_I2C_STAT);
+        data = qtest_readw(i2c->qts, s->addr + OMAP_I2C_STAT);
         g_assert((data & OMAP_I2C_STAT_XRDY) != 0);
 
         data = buf[0];
-        writew(s->addr + OMAP_I2C_DATA, data);
+        qtest_writew(i2c->qts, s->addr + OMAP_I2C_DATA, data);
     }
 
-    data = readw(s->addr + OMAP_I2C_CON);
+    data = qtest_readw(i2c->qts, s->addr + OMAP_I2C_CON);
     g_assert((data & OMAP_I2C_CON_STP) == 0);
 }
 
@@ -109,30 +109,30 @@ static void omap_i2c_recv(I2CAdapter *i2c, uint8_t addr,
     omap_i2c_set_slave_addr(s, addr);
 
     data = len;
-    writew(s->addr + OMAP_I2C_CNT, data);
+    qtest_writew(i2c->qts, s->addr + OMAP_I2C_CNT, data);
 
     data = OMAP_I2C_CON_I2C_EN |
            OMAP_I2C_CON_MST |
            OMAP_I2C_CON_STT |
            OMAP_I2C_CON_STP;
-    writew(s->addr + OMAP_I2C_CON, data);
-    data = readw(s->addr + OMAP_I2C_CON);
+    qtest_writew(i2c->qts, s->addr + OMAP_I2C_CON, data);
+    data = qtest_readw(i2c->qts, s->addr + OMAP_I2C_CON);
     g_assert((data & OMAP_I2C_CON_STP) == 0);
 
-    data = readw(s->addr + OMAP_I2C_STAT);
+    data = qtest_readw(i2c->qts, s->addr + OMAP_I2C_STAT);
     g_assert((data & OMAP_I2C_STAT_NACK) == 0);
 
-    data = readw(s->addr + OMAP_I2C_CNT);
+    data = qtest_readw(i2c->qts, s->addr + OMAP_I2C_CNT);
     g_assert_cmpuint(data, ==, len);
 
     while (len > 0) {
-        data = readw(s->addr + OMAP_I2C_STAT);
+        data = qtest_readw(i2c->qts, s->addr + OMAP_I2C_STAT);
         g_assert((data & OMAP_I2C_STAT_RRDY) != 0);
         g_assert((data & OMAP_I2C_STAT_ROVR) == 0);
 
-        data = readw(s->addr + OMAP_I2C_DATA);
+        data = qtest_readw(i2c->qts, s->addr + OMAP_I2C_DATA);
 
-        stat = readw(s->addr + OMAP_I2C_STAT);
+        stat = qtest_readw(i2c->qts, s->addr + OMAP_I2C_STAT);
 
         if (unlikely(len == 1)) {
             g_assert((stat & OMAP_I2C_STAT_SBD) != 0);
@@ -148,11 +148,11 @@ static void omap_i2c_recv(I2CAdapter *i2c, uint8_t addr,
         }
     }
 
-    data = readw(s->addr + OMAP_I2C_CON);
+    data = qtest_readw(i2c->qts, s->addr + OMAP_I2C_CON);
     g_assert((data & OMAP_I2C_CON_STP) == 0);
 }
 
-I2CAdapter *omap_i2c_create(uint64_t addr)
+I2CAdapter *omap_i2c_create(QTestState *qts, uint64_t addr)
 {
     OMAPI2C *s = g_malloc0(sizeof(*s));
     I2CAdapter *i2c = (I2CAdapter *)s;
@@ -162,9 +162,10 @@ I2CAdapter *omap_i2c_create(uint64_t addr)
 
     i2c->send = omap_i2c_send;
     i2c->recv = omap_i2c_recv;
+    i2c->qts = qts;
 
     /* verify the mmio address by looking for a known signature */
-    data = readw(addr + OMAP_I2C_REV);
+    data = qtest_readw(qts, addr + OMAP_I2C_REV);
     g_assert_cmphex(data, ==, 0x34);
 
     return i2c;
diff --git a/tests/libqos/i2c.h b/tests/libqos/i2c.h
index 6e648f9..eb40b80 100644
--- a/tests/libqos/i2c.h
+++ b/tests/libqos/i2c.h
@@ -9,6 +9,7 @@
 #ifndef LIBQOS_I2C_H
 #define LIBQOS_I2C_H
 
+#include "libqtest.h"
 
 typedef struct I2CAdapter I2CAdapter;
 struct I2CAdapter {
@@ -16,6 +17,8 @@ struct I2CAdapter {
                  const uint8_t *buf, uint16_t len);
     void (*recv)(I2CAdapter *adapter, uint8_t addr,
                  uint8_t *buf, uint16_t len);
+
+    QTestState *qts;
 };
 
 void i2c_send(I2CAdapter *i2c, uint8_t addr,
@@ -24,9 +27,9 @@ void i2c_recv(I2CAdapter *i2c, uint8_t addr,
               uint8_t *buf, uint16_t len);
 
 /* libi2c-omap.c */
-I2CAdapter *omap_i2c_create(uint64_t addr);
+I2CAdapter *omap_i2c_create(QTestState *qts, uint64_t addr);
 
 /* libi2c-imx.c */
-I2CAdapter *imx_i2c_create(uint64_t addr);
+I2CAdapter *imx_i2c_create(QTestState *qts, uint64_t addr);
 
 #endif
diff --git a/tests/tmp105-test.c b/tests/tmp105-test.c
index a7940a4..382f88b 100644
--- a/tests/tmp105-test.c
+++ b/tests/tmp105-test.c
@@ -154,15 +154,13 @@ int main(int argc, char **argv)
     s = qtest_start("-machine n800 "
                     "-device tmp105,bus=i2c-bus.0,id=" TMP105_TEST_ID
                     ",address=0x49");
-    i2c = omap_i2c_create(OMAP2_I2C_1_BASE);
+    i2c = omap_i2c_create(s, OMAP2_I2C_1_BASE);
 
     qtest_add_func("/tmp105/tx-rx", send_and_receive);
 
     ret = g_test_run();
 
-    if (s) {
-        qtest_quit(s);
-    }
+    qtest_quit(s);
     g_free(i2c);
 
     return ret;
