hw/misc: add an EMC141{3,4} device model

Largely inspired by the TMP421 temperature sensor, here is a model for
the EMC1413/EMC1414 temperature sensors.

Specs can be found here :
  http://ww1.microchip.com/downloads/en/DeviceDoc/20005274A.pdf

Signed-off-by: John Wang <wangzhiqiang.bj@bytedance.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20201122105134.671-1-wangzhiqiang.bj@bytedance.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>

2 files changed, 82 insertions, 0 deletions

diff --git a/tests/qtest/emc141x-test.c b/tests/qtest/emc141x-test.c
new file mode 100644
index 0000000000..714058806a
--- /dev/null
+++ b/tests/qtest/emc141x-test.c
@@ -0,0 +1,81 @@
+/*
+ * QTest testcase for the EMC141X temperature sensor
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+
+#include "libqtest-single.h"
+#include "libqos/qgraph.h"
+#include "libqos/i2c.h"
+#include "qapi/qmp/qdict.h"
+#include "hw/misc/emc141x_regs.h"
+
+#define EMC1414_TEST_ID   "emc1414-test"
+
+static int qmp_emc1414_get_temperature(const char *id)
+{
+    QDict *response;
+    int ret;
+
+    response = qmp("{ 'execute': 'qom-get', 'arguments': { 'path': %s, "
+                   "'property': 'temperature0' } }", id);
+    g_assert(qdict_haskey(response, "return"));
+    ret = qdict_get_int(response, "return");
+    qobject_unref(response);
+    return ret;
+}
+
+static void qmp_emc1414_set_temperature(const char *id, int value)
+{
+    QDict *response;
+
+    response = qmp("{ 'execute': 'qom-set', 'arguments': { 'path': %s, "
+                   "'property': 'temperature0', 'value': %d } }", id, value);
+    g_assert(qdict_haskey(response, "return"));
+    qobject_unref(response);
+}
+
+static void send_and_receive(void *obj, void *data, QGuestAllocator *alloc)
+{
+    uint16_t value;
+    QI2CDevice *i2cdev = (QI2CDevice *)obj;
+
+    value = qmp_emc1414_get_temperature(EMC1414_TEST_ID);
+    g_assert_cmpuint(value, ==, 0);
+
+    value = i2c_get8(i2cdev, EMC141X_TEMP_HIGH0);
+    g_assert_cmphex(value, ==, 0);
+
+    /* The default max value is 85C, 0x55=85 */
+    value = i2c_get8(i2cdev, EMC141X_TEMP_MAX_HIGH0);
+    g_assert_cmphex(value, ==, 0x55);
+
+    value = i2c_get8(i2cdev, EMC141X_TEMP_MIN_HIGH0);
+    g_assert_cmphex(value, ==, 0);
+
+    /* 3000mc = 30C */
+    qmp_emc1414_set_temperature(EMC1414_TEST_ID, 30000);
+    value = qmp_emc1414_get_temperature(EMC1414_TEST_ID);
+    g_assert_cmpuint(value, ==, 30000);
+
+    value = i2c_get8(i2cdev, EMC141X_TEMP_HIGH0);
+    g_assert_cmphex(value, ==, 30);
+
+}
+
+static void emc1414_register_nodes(void)
+{
+    QOSGraphEdgeOptions opts = {
+        .extra_device_opts = "id=" EMC1414_TEST_ID ",address=0x70"
+    };
+    add_qi2c_address(&opts, &(QI2CAddress) { 0x70 });
+
+    qos_node_create_driver("emc1414", i2c_device_create);
+    qos_node_consumes("emc1414", "i2c-bus", &opts);
+
+    qos_add_test("tx-rx", "emc1414", send_and_receive, NULL);
+}
+libqos_init(emc1414_register_nodes);
diff --git a/tests/qtest/meson.build b/tests/qtest/meson.build
index c19f1c8503..d776befd6e 100644
--- a/tests/qtest/meson.build
+++ b/tests/qtest/meson.build
@@ -188,6 +188,7 @@ qos_test_ss.add(
   'sdhci-test.c',
   'spapr-phb-test.c',
   'tmp105-test.c',
+  'emc141x-test.c',
   'usb-hcd-ohci-test.c',
   'virtio-test.c',
   'virtio-blk-test.c',