}
/* These are only stubs now. */
-static void pxa2xx_i2c_event(I2CSlave *i2c, enum i2c_event event)
+static int pxa2xx_i2c_event(I2CSlave *i2c, enum i2c_event event)
{
PXA2xxI2CSlaveState *slave = PXA2XX_I2C_SLAVE(i2c);
PXA2xxI2CState *s = slave->host;
break;
}
pxa2xx_i2c_update(s);
+
+ return 0;
}
static int pxa2xx_i2c_rx(I2CSlave *i2c)
return 0;
}
-static void tosa_dac_event(I2CSlave *i2c, enum i2c_event event)
+static int tosa_dac_event(I2CSlave *i2c, enum i2c_event event)
{
TosaDACState *s = TOSA_DAC(i2c);
default:
break;
}
+
+ return 0;
}
static int tosa_dac_recv(I2CSlave *s)
return 0;
}
-static void aer915_event(I2CSlave *i2c, enum i2c_event event)
+static int aer915_event(I2CSlave *i2c, enum i2c_event event)
{
AER915State *s = AER915(i2c);
default:
break;
}
+
+ return 0;
}
static int aer915_recv(I2CSlave *slave)
s->i2c_len = 0;
}
-static void wm8750_event(I2CSlave *i2c, enum i2c_event event)
+static int wm8750_event(I2CSlave *i2c, enum i2c_event event)
{
WM8750State *s = WM8750(i2c);
default:
break;
}
+
+ return 0;
}
#define WM8750_LINVOL 0x00
return 0;
}
-static void ssd0303_event(I2CSlave *i2c, enum i2c_event event)
+static int ssd0303_event(I2CSlave *i2c, enum i2c_event event)
{
ssd0303_state *s = SSD0303(i2c);
/* Nothing to do. */
break;
}
+
+ return 0;
}
static void ssd0303_update_display(void *opaque)
return 0;
}
-static void max7310_event(I2CSlave *i2c, enum i2c_event event)
+static int max7310_event(I2CSlave *i2c, enum i2c_event event)
{
MAX7310State *s = MAX7310(i2c);
s->len = 0;
default:
break;
}
+
+ return 0;
}
static const VMStateDescription vmstate_max7310 = {
return !QLIST_EMPTY(&bus->current_devs);
}
+/* TODO: Make this handle multiple masters. */
/*
- * Returns non-zero if the address is not valid. If this is called
- * again without an intervening i2c_end_transfer(), like in the SMBus
- * case where the operation is switched from write to read, this
- * function will not rescan the bus and thus cannot fail.
+ * Start or continue an i2c transaction. When this is called for the
+ * first time or after an i2c_end_transfer(), if it returns an error
+ * the bus transaction is terminated (or really never started). If
+ * this is called after another i2c_start_transfer() without an
+ * intervening i2c_end_transfer(), and it returns an error, the
+ * transaction will not be terminated. The caller must do it.
+ *
+ * This corresponds with the way real hardware works. The SMBus
+ * protocol uses a start transfer to switch from write to read mode
+ * without releasing the bus. If that fails, the bus is still
+ * in a transaction.
*/
-/* TODO: Make this handle multiple masters. */
int i2c_start_transfer(I2CBus *bus, uint8_t address, int recv)
{
BusChild *kid;
I2CSlaveClass *sc;
I2CNode *node;
+ bool bus_scanned = false;
if (address == I2C_BROADCAST) {
/*
}
}
}
+ bus_scanned = true;
}
if (QLIST_EMPTY(&bus->current_devs)) {
}
QLIST_FOREACH(node, &bus->current_devs, next) {
+ int rv;
+
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);
+ rv = sc->event(node->elt, recv ? I2C_START_RECV : I2C_START_SEND);
+ if (rv && !bus->broadcast) {
+ if (bus_scanned) {
+ /* First call, terminate the transfer. */
+ i2c_end_transfer(bus);
+ }
+ return rv;
+ }
}
}
return 0;
s->reg = 0;
}
-static void i2c_ddc_event(I2CSlave *i2c, enum i2c_event event)
+static int i2c_ddc_event(I2CSlave *i2c, enum i2c_event event)
{
I2CDDCState *s = I2CDDC(i2c);
if (event == I2C_START_SEND) {
s->firstbyte = true;
}
+
+ return 0;
}
static int i2c_ddc_rx(I2CSlave *i2c)
}
}
-static void smbus_i2c_event(I2CSlave *s, enum i2c_event event)
+static int smbus_i2c_event(I2CSlave *s, enum i2c_event event)
{
SMBusDevice *dev = SMBUS_DEVICE(s);
break;
}
}
+
+ return 0;
}
static int smbus_i2c_recv(I2CSlave *s)
}
i2c_send(bus, command);
if (i2c_start_transfer(bus, addr, 1)) {
- assert(0);
+ i2c_end_transfer(bus);
+ return -1;
}
data = i2c_recv(bus);
i2c_nack(bus);
}
i2c_send(bus, command);
if (i2c_start_transfer(bus, addr, 1)) {
- assert(0);
+ i2c_end_transfer(bus);
+ return -1;
}
data = i2c_recv(bus);
data |= i2c_recv(bus) << 8;
}
i2c_send(bus, command);
if (i2c_start_transfer(bus, addr, 1)) {
- assert(0);
+ i2c_end_transfer(bus);
+ return -1;
}
len = i2c_recv(bus);
if (len > 32) {
}
}
-static void lm_i2c_event(I2CSlave *i2c, enum i2c_event event)
+static int lm_i2c_event(I2CSlave *i2c, enum i2c_event event)
{
LM823KbdState *s = LM8323(i2c);
default:
break;
}
+
+ return 0;
}
static int lm_i2c_rx(I2CSlave *i2c)
return 0;
}
-static void tmp105_event(I2CSlave *i2c, enum i2c_event event)
+static int tmp105_event(I2CSlave *i2c, enum i2c_event event)
{
TMP105State *s = TMP105(i2c);
}
s->len = 0;
+ return 0;
}
static int tmp105_post_load(void *opaque, int version_id)
}
}
-static void ds1338_event(I2CSlave *i2c, enum i2c_event event)
+static int ds1338_event(I2CSlave *i2c, enum i2c_event event)
{
DS1338State *s = DS1338(i2c);
default:
break;
}
+
+ return 0;
}
static int ds1338_recv(I2CSlave *i2c)
}
}
-static void menelaus_event(I2CSlave *i2c, enum i2c_event event)
+static int menelaus_event(I2CSlave *i2c, enum i2c_event event)
{
MenelausState *s = TWL92230(i2c);
if (event == I2C_START_SEND)
s->firstbyte = 1;
+
+ return 0;
}
static int menelaus_tx(I2CSlave *i2c, uint8_t data)
/* Callbacks provided by the device. */
int (*init)(I2CSlave *dev);
- /* Master to slave. */
+ /* Master to slave. Returns non-zero for a NAK, 0 for success. */
int (*send)(I2CSlave *s, uint8_t data);
- /* Slave to master. */
+ /*
+ * Slave to master. This cannot fail, the device should always
+ * return something here. Negative values probably result in 0xff
+ * and a possible log from the driver, and shouldn't be used.
+ */
int (*recv)(I2CSlave *s);
- /* Notify the slave of a bus state change. */
- void (*event)(I2CSlave *s, enum i2c_event event);
+ /*
+ * Notify the slave of a bus state change. For start event,
+ * returns non-zero to NAK an operation. For other events the
+ * return code is not used and should be zero.
+ */
+ int (*event)(I2CSlave *s, enum i2c_event event);
} I2CSlaveClass;
struct I2CSlave
projects / qemu.git / commitdiff