[PATCH 1/2] hw/misc: add an EMC141{3,4} device model

[John Wang]

Largely inspired by the TMP423 temperature sensor, here is a model for
the EMC1413 temperature sensors.

Specs can be found here :
  https://pdf1.alldatasheet.com/datasheet-pdf/view/533713/SMSC/EMC1413.html

Signed-off-by: John Wang <wangzhiqiang.bj@bytedance.com>
---
 hw/arm/Kconfig      |   1 +
 hw/misc/Kconfig     |   4 +
 hw/misc/emc1413.c   | 309 ++++++++++++++++++++++++++++++++++++++++++++
 hw/misc/meson.build |   1 +
 4 files changed, 315 insertions(+)
 create mode 100644 hw/misc/emc1413.c

diff --git a/hw/arm/Kconfig b/hw/arm/Kconfig
index f303c6bead..8801ada145 100644
--- a/hw/arm/Kconfig
+++ b/hw/arm/Kconfig
@@ -402,6 +402,7 @@ config ASPEED_SOC
     select SSI_M25P80
     select TMP105
     select TMP421
+    select EMC1413
     select UNIMP
 
 config MPS2
diff --git a/hw/misc/Kconfig b/hw/misc/Kconfig
index 3185456110..91badf2d4d 100644
--- a/hw/misc/Kconfig
+++ b/hw/misc/Kconfig
@@ -13,6 +13,10 @@ config TMP421
     bool
     depends on I2C
 
+config EMC1413
+    bool
+    depends on I2C
+
 config ISA_DEBUG
     bool
     depends on ISA_BUS
diff --git a/hw/misc/emc1413.c b/hw/misc/emc1413.c
new file mode 100644
index 0000000000..2430c3f074
--- /dev/null
+++ b/hw/misc/emc1413.c
@@ -0,0 +1,309 @@
+/*
+ * SMSC EMC1413 temperature sensor.
+ *
+ * Copyright (c) 2020 Bytedance Corporation
+ * Written by John Wang <wangzhiqiang.bj@bytedance.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 or
+ * (at your option) version 3 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "qemu/osdep.h"
+#include "hw/i2c/i2c.h"
+#include "migration/vmstate.h"
+#include "qapi/error.h"
+#include "qapi/visitor.h"
+#include "qemu/module.h"
+#include "qom/object.h"
+
+#define DEVICE_ID_REG                    0xfd
+#define MANUFACTURER_ID_REG              0xfe
+#define REVISION_REG                     0xff
+#define EMC1413_DEVICE_ID                0x21
+#define EMC1414_DEVICE_ID                0x25
+
+typedef struct DeviceInfo {
+    uint8_t model;
+    const char *name;
+} DeviceInfo;
+
+static const DeviceInfo devices[] = {
+    { EMC1413_DEVICE_ID, "emc1413" },
+    { EMC1414_DEVICE_ID, "emc1414" },
+};
+
+struct EMC1413State {
+    I2CSlave i2c;
+    uint8_t temperature[4];
+    uint8_t min[4];
+    uint8_t max[4];
+    uint8_t len;
+    uint8_t data;
+    uint8_t pointer;
+
+};
+
+struct EMC1413Class {
+    I2CSlaveClass parent_class;
+    DeviceInfo *dev;
+};
+
+#define TYPE_EMC1413 "emc1413-generic"
+OBJECT_DECLARE_TYPE(EMC1413State, EMC1413Class, EMC1413)
+
+
+/* the EMC1413 registers */
+#define EMC1413_TEMP_HIGH0               0x00
+#define EMC1413_TEMP_HIGH1               0x01
+#define EMC1413_TEMP_HIGH2               0x23
+#define EMC1413_TEMP_HIGH3               0x2a
+#define EMC1413_TEMP_MAX_HIGH0           0x05
+#define EMC1413_TEMP_MIN_HIGH0           0x06
+#define EMC1413_TEMP_MAX_HIGH1           0x07
+#define EMC1413_TEMP_MIN_HIGH1           0x08
+#define EMC1413_TEMP_MAX_HIGH2           0x15
+#define EMC1413_TEMP_MIN_HIGH2           0x16
+#define EMC1413_TEMP_MAX_HIGH3           0x2c
+#define EMC1413_TEMP_MIN_HIGH3           0x2d
+
+static void emc1413_get_temperature(Object *obj, Visitor *v, const char *name,
+                                   void *opaque, Error **errp)
+{
+    EMC1413State *s = EMC1413(obj);
+    int64_t value;
+    int tempid;
+
+    if (sscanf(name, "temperature%d", &tempid) != 1) {
+        error_setg(errp, "error reading %s: %s", name, g_strerror(errno));
+        return;
+    }
+
+    if (tempid >= 4 || tempid < 0) {
+        error_setg(errp, "error reading %s", name);
+        return;
+    }
+
+    value = s->temperature[tempid] * 1000;
+
+    visit_type_int(v, name, &value, errp);
+}
+
+static void emc1413_set_temperature(Object *obj, Visitor *v, const char *name,
+                                   void *opaque, Error **errp)
+{
+    EMC1413State *s = EMC1413(obj);
+    int64_t temp;
+    int tempid;
+
+    if (!visit_type_int(v, name, &temp, errp)) {
+        return;
+    }
+
+    if (sscanf(name, "temperature%d", &tempid) != 1) {
+        error_setg(errp, "error reading %s: %s", name, g_strerror(errno));
+        return;
+    }
+
+    if (tempid >= 4 || tempid < 0) {
+        error_setg(errp, "error reading %s", name);
+        return;
+    }
+
+    s->temperature[tempid] = temp / 1000;
+}
+
+struct emc1413_reg {
+    uint8_t addr;
+    uint8_t *data;
+};
+
+static void emc1413_read(EMC1413State *s)
+{
+    EMC1413Class *sc = EMC1413_GET_CLASS(s);
+    uint8_t smsc_manufacturer_id = 0x5d;
+    uint8_t revision = 0x04;
+    struct emc1413_reg emc1413_regs[] = {
+        {DEVICE_ID_REG, &sc->dev->model},
+        {MANUFACTURER_ID_REG, &smsc_manufacturer_id},
+        {REVISION_REG, &revision},
+        {EMC1413_TEMP_HIGH0, &s->temperature[0]},
+        {EMC1413_TEMP_HIGH1, &s->temperature[1]},
+        {EMC1413_TEMP_HIGH2, &s->temperature[2]},
+        {EMC1413_TEMP_HIGH3, &s->temperature[3]},
+        {EMC1413_TEMP_MAX_HIGH0, &s->max[0]},
+        {EMC1413_TEMP_MAX_HIGH1, &s->max[1]},
+        {EMC1413_TEMP_MAX_HIGH2, &s->max[2]},
+        {EMC1413_TEMP_MAX_HIGH3, &s->max[3]},
+        {EMC1413_TEMP_MIN_HIGH0, &s->min[0]},
+        {EMC1413_TEMP_MIN_HIGH1, &s->min[1]},
+        {EMC1413_TEMP_MIN_HIGH2, &s->min[2]},
+        {EMC1413_TEMP_MIN_HIGH3, &s->min[3]},
+    };
+    size_t i;
+    for (i = 0; i < ARRAY_SIZE(emc1413_regs); i++) {
+        if (emc1413_regs[i].addr == s->pointer) {
+            s->data = *(emc1413_regs[i].data);
+            return;
+        }
+    }
+}
+
+static void emc1413_write(EMC1413State *s)
+{
+    struct emc1413_reg emc1413_regs[] = {
+        {EMC1413_TEMP_MAX_HIGH0, &s->max[0]},
+        {EMC1413_TEMP_MAX_HIGH1, &s->max[1]},
+        {EMC1413_TEMP_MAX_HIGH2, &s->max[2]},
+        {EMC1413_TEMP_MAX_HIGH3, &s->max[3]},
+        {EMC1413_TEMP_MIN_HIGH0, &s->min[0]},
+        {EMC1413_TEMP_MIN_HIGH1, &s->min[1]},
+        {EMC1413_TEMP_MIN_HIGH2, &s->min[2]},
+        {EMC1413_TEMP_MIN_HIGH3, &s->min[3]},
+    };
+    size_t i;
+    for (i = 0; i < ARRAY_SIZE(emc1413_regs); i++) {
+        if (emc1413_regs[i].addr == s->pointer) {
+            *(emc1413_regs[i].data) = s->data;
+            return;
+        }
+    }
+}
+
+static uint8_t emc1413_rx(I2CSlave *i2c)
+{
+    EMC1413State *s = EMC1413(i2c);
+
+    if (s->len == 0) {
+        s->len++;
+        return s->data;
+    } else {
+        return 0xff;
+    }
+}
+
+static int emc1413_tx(I2CSlave *i2c, uint8_t data)
+{
+    EMC1413State *s = EMC1413(i2c);
+
+    if (s->len == 0) {
+        /* first byte is the reg pointer */
+        s->pointer = data;
+        s->len++;
+    } else if (s->len == 1) {
+        s->data = data;
+        emc1413_write(s);
+    }
+
+    return 0;
+}
+
+static int emc1413_event(I2CSlave *i2c, enum i2c_event event)
+{
+    EMC1413State *s = EMC1413(i2c);
+
+    if (event == I2C_START_RECV) {
+        emc1413_read(s);
+    }
+
+    s->len = 0;
+    return 0;
+}
+
+static const VMStateDescription vmstate_emc1413 = {
+    .name = "EMC1413",
+    .version_id = 0,
+    .minimum_version_id = 0,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT8(len, EMC1413State),
+        VMSTATE_UINT8(data, EMC1413State),
+        VMSTATE_UINT8(pointer, EMC1413State),
+        VMSTATE_UINT8_ARRAY(temperature, EMC1413State, 4),
+        VMSTATE_I2C_SLAVE(i2c, EMC1413State),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static void emc1413_reset(I2CSlave *i2c)
+{
+    EMC1413State *s = EMC1413(i2c);
+
+    memset(s->temperature, 0, sizeof(s->temperature));
+    memset(s->min, 0, sizeof(s->min));
+    memset(s->max, 0x55, sizeof(s->max));
+    s->pointer = 0;
+    s->len = 0;
+}
+
+static void emc1413_realize(DeviceState *dev, Error **errp)
+{
+    EMC1413State *s = EMC1413(dev);
+
+    emc1413_reset(&s->i2c);
+}
+
+static void emc1413_initfn(Object *obj)
+{
+    object_property_add(obj, "temperature0", "int",
+                        emc1413_get_temperature,
+                        emc1413_set_temperature, NULL, NULL);
+    object_property_add(obj, "temperature1", "int",
+                        emc1413_get_temperature,
+                        emc1413_set_temperature, NULL, NULL);
+    object_property_add(obj, "temperature2", "int",
+                        emc1413_get_temperature,
+                        emc1413_set_temperature, NULL, NULL);
+    object_property_add(obj, "temperature3", "int",
+                        emc1413_get_temperature,
+                        emc1413_set_temperature, NULL, NULL);
+}
+
+static void emc1413_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+    I2CSlaveClass *k = I2C_SLAVE_CLASS(klass);
+    EMC1413Class *sc = EMC1413_CLASS(klass);
+
+    dc->realize = emc1413_realize;
+    k->event = emc1413_event;
+    k->recv = emc1413_rx;
+    k->send = emc1413_tx;
+    dc->vmsd = &vmstate_emc1413;
+    sc->dev = (DeviceInfo *) data;
+}
+
+static const TypeInfo emc1413_info = {
+    .name          = TYPE_EMC1413,
+    .parent        = TYPE_I2C_SLAVE,
+    .instance_size = sizeof(EMC1413State),
+    .class_size    = sizeof(EMC1413Class),
+    .instance_init = emc1413_initfn,
+    .abstract      = true,
+};
+
+static void emc1413_register_types(void)
+{
+    int i;
+
+    type_register_static(&emc1413_info);
+    for (i = 0; i < ARRAY_SIZE(devices); ++i) {
+        TypeInfo ti = {
+            .name       = devices[i].name,
+            .parent     = TYPE_EMC1413,
+            .class_init = emc1413_class_init,
+            .class_data = (void *) &devices[i],
+        };
+        type_register(&ti);
+    }
+}
+
+type_init(emc1413_register_types)
diff --git a/hw/misc/meson.build b/hw/misc/meson.build
index 793d45b1dc..08821c72ba 100644
--- a/hw/misc/meson.build
+++ b/hw/misc/meson.build
@@ -9,6 +9,7 @@ softmmu_ss.add(when: 'CONFIG_PCI_TESTDEV', if_true: 
files('pci-testdev.c'))
 softmmu_ss.add(when: 'CONFIG_SGA', if_true: files('sga.c'))
 softmmu_ss.add(when: 'CONFIG_TMP105', if_true: files('tmp105.c'))
 softmmu_ss.add(when: 'CONFIG_TMP421', if_true: files('tmp421.c'))
+softmmu_ss.add(when: 'CONFIG_EMC1413', if_true: files('emc1413.c'))
 softmmu_ss.add(when: 'CONFIG_UNIMP', if_true: files('unimp.c'))
 softmmu_ss.add(when: 'CONFIG_EMPTY_SLOT', if_true: files('empty_slot.c'))
 
-- 
2.25.1