From: KONRAD Frederic <fred.kon...@greensocs.com>
This does a write to every slaves when the I2C bus get a write to address 0.
Signed-off-by: KONRAD Frederic <fred.kon...@greensocs.com>
Reviewed-by: Alistair Francis <alistair.fran...@xilinx.com>
Reviewed-by: Peter Crosthwaite <crosthwaite.pe...@gmail.com>
Tested-By: Hyun Kwon <hyun.k...@xilinx.com>
---
hw/i2c/core.c | 129 ++++++++++++++++++++++++++++++++++------------------------
1 file changed, 75 insertions(+), 54 deletions(-)
diff --git a/hw/i2c/core.c b/hw/i2c/core.c
index 013ff68..a3921d9 100644
--- a/hw/i2c/core.c
+++ b/hw/i2c/core.c
@@ -10,11 +10,19 @@
#include "qemu/osdep.h"
#include "hw/i2c/i2c.h"
+typedef struct I2CNode I2CNode;
+
+struct I2CNode {
+ I2CSlave *elt;
+ QLIST_ENTRY(I2CNode) next;
+};
+
struct I2CBus
{
BusState qbus;
- I2CSlave *current_dev;
+ QLIST_HEAD(, I2CNode) current_devs;
uint8_t saved_address;
+ bool broadcast;
};
static Property i2c_props[] = {
@@ -35,17 +43,12 @@ static void i2c_bus_pre_save(void *opaque)
{
I2CBus *bus = opaque;
- bus->saved_address = bus->current_dev ? bus->current_dev->address : -1;
-}
-
-static int i2c_bus_post_load(void *opaque, int version_id)
-{
- I2CBus *bus = opaque;
-
- /* The bus is loaded before attached devices, so load and save the
- current device id. Devices will check themselves as loaded. */
- bus->current_dev = NULL;
- return 0;
+ bus->saved_address = -1;
+ if (!QLIST_EMPTY(&bus->current_devs)) {
+ if (!bus->broadcast) {
+ bus->saved_address = QLIST_FIRST(&bus->current_devs)->elt->address;
+ }
+ }
}
static const VMStateDescription vmstate_i2c_bus = {
@@ -53,9 +56,9 @@ static const VMStateDescription vmstate_i2c_bus = {
.version_id = 1,
.minimum_version_id = 1,
.pre_save = i2c_bus_pre_save,
- .post_load = i2c_bus_post_load,
.fields = (VMStateField[]) {
VMSTATE_UINT8(saved_address, I2CBus),
+ VMSTATE_BOOL(broadcast, I2CBus),
VMSTATE_END_OF_LIST()
}
};
@@ -78,7 +81,7 @@ void i2c_set_slave_address(I2CSlave *dev, uint8_t address)
/* Return nonzero if bus is busy. */
int i2c_bus_busy(I2CBus *bus)
{
- return bus->current_dev != NULL;
+ return !QLIST_EMPTY(&bus->current_devs);
}
/* Returns non-zero if the address is not valid. */
@@ -86,95 +89,109 @@ int i2c_bus_busy(I2CBus *bus)
int i2c_start_transfer(I2CBus *bus, uint8_t address, int recv)
{
BusChild *kid;
- I2CSlave *slave = NULL;
I2CSlaveClass *sc;
+ I2CNode *node;
+
+ if (address == 0x00) {
+ /*
+ * This is a broadcast, the current_devs will be all the devices of the
+ * bus.
+ */
+ bus->broadcast = true;
+ }
QTAILQ_FOREACH(kid, &bus->qbus.children, sibling) {
DeviceState *qdev = kid->child;
I2CSlave *candidate = I2C_SLAVE(qdev);
- if (candidate->address == address) {
- slave = candidate;
- break;
+ if ((candidate->address == address) || (bus->broadcast)) {
+ node = g_malloc(sizeof(struct I2CNode));
+ node->elt = candidate;
+ QLIST_INSERT_HEAD(&bus->current_devs, node, next);
+ if (!bus->broadcast) {
+ break;
+ }
}
}
- if (!slave) {
+ if (QLIST_EMPTY(&bus->current_devs)) {
return 1;
}
- sc = I2C_SLAVE_GET_CLASS(slave);
- /* If the bus is already busy, assume this is a repeated
- start condition. */
- bus->current_dev = slave;
- if (sc->event) {
- sc->event(slave, recv ? I2C_START_RECV : I2C_START_SEND);
+ QLIST_FOREACH(node, &bus->current_devs, next) {
+ sc = I2C_SLAVE_GET_CLASS(node->elt);
+ /* If the bus is already busy, assume this is a repeated
+ start condition. */
+ if (sc->event) {
+ sc->event(node->elt, recv ? I2C_START_RECV : I2C_START_SEND);
+ }
}
return 0;
}
void i2c_end_transfer(I2CBus *bus)
{
- I2CSlave *dev = bus->current_dev;
I2CSlaveClass *sc;
+ I2CNode *node;
- if (!dev) {
+ if (QLIST_EMPTY(&bus->current_devs)) {
return;
}
- sc = I2C_SLAVE_GET_CLASS(dev);
- if (sc->event) {
- sc->event(dev, I2C_FINISH);
+ QLIST_FOREACH(node, &bus->current_devs, next) {
+ sc = I2C_SLAVE_GET_CLASS(node->elt);
+ if (sc->event) {
+ sc->event(node->elt, I2C_FINISH);
+ }
+ QLIST_REMOVE(node, next);
+ g_free(node);
}
-
- bus->current_dev = NULL;
+ bus->broadcast = false;
}
int i2c_send(I2CBus *bus, uint8_t data)
{
- I2CSlave *dev = bus->current_dev;
I2CSlaveClass *sc;
+ I2CNode *node;
+ int ret = -1;
- if (!dev) {
- return -1;
- }
-
- sc = I2C_SLAVE_GET_CLASS(dev);
- if (sc->send) {
- return sc->send(dev, data);
+ QLIST_FOREACH(node, &bus->current_devs, next) {
+ sc = I2C_SLAVE_GET_CLASS(node->elt);
+ if (sc->send) {
+ ret |= sc->send(node->elt, data);
+ }
}
-
- return -1;
+ return ret;
}
int i2c_recv(I2CBus *bus)
{
- I2CSlave *dev = bus->current_dev;
I2CSlaveClass *sc;
- if (!dev) {
+ if ((QLIST_EMPTY(&bus->current_devs)) || (bus->broadcast)) {
return -1;
}
- sc = I2C_SLAVE_GET_CLASS(dev);
+ sc = I2C_SLAVE_GET_CLASS(QLIST_FIRST(&bus->current_devs)->elt);
if (sc->recv) {
- return sc->recv(dev);
+ return sc->recv(QLIST_FIRST(&bus->current_devs)->elt);
}
-
return -1;
}
void i2c_nack(I2CBus *bus)
{
- I2CSlave *dev = bus->current_dev;
I2CSlaveClass *sc;
+ I2CNode *node;
- if (!dev) {
+ if (QLIST_EMPTY(&bus->current_devs)) {
return;
}
- sc = I2C_SLAVE_GET_CLASS(dev);
- if (sc->event) {
- sc->event(dev, I2C_NACK);
+ QLIST_FOREACH(node, &bus->current_devs, next) {
+ sc = I2C_SLAVE_GET_CLASS(node->elt);
+ if (sc->event) {
+ sc->event(node->elt, I2C_NACK);
+ }
}
}
@@ -182,9 +199,13 @@ static int i2c_slave_post_load(void *opaque, int
version_id)
{
I2CSlave *dev = opaque;
I2CBus *bus;
+ I2CNode *node;
+
bus = I2C_BUS(qdev_get_parent_bus(DEVICE(dev)));
- if (bus->saved_address == dev->address) {
- bus->current_dev = dev;
+ if ((bus->saved_address == dev->address) || (bus->broadcast)) {
+ node = g_malloc(sizeof(struct I2CNode));
+ node->elt = dev;
+ QLIST_INSERT_HEAD(&bus->current_devs, node, next);
}
return 0;
}
--
1.9.0
