On 2021/4/1 20:12, Viresh Kumar wrote:
+
+/* vhost-user-i2c definitions */
+
+#define MAX_I2C_VDEV (1 << 7)
+#define MAX_I2C_ADAPTER 16
Generally speaking, 16 is big enough for most cases. But comparing with
static configuration,
I think it is better if we can check how many adapters in the host when
doing initialization and
use that number as "MAX_I2C_ADAPTER".
+
+static VI2cAdapter *vi2c_create_adapter(int32_t bus, uint16_t client_addr[],
+ int32_t n_client)
+{
+ VI2cAdapter *adapter;
+ char path[20];
+ uint64_t funcs;
+ int32_t fd, i;
+
+ if (bus < 0) {
+ return NULL;
+ }
+
+ adapter = g_malloc0(sizeof(*adapter));
+ if (!adapter) {
+ g_printerr("failed to alloc adapter");
+ return NULL;
+ }
+
+ snprintf(path, sizeof(path), "/dev/i2c-%d", bus);
+ path[sizeof(path) - 1] = '\0';
+
+ fd = open(path, O_RDWR);
+ if (fd < 0) {
+ g_printerr("virtio_i2c: failed to open %s\n", path);
+ goto fail;
+ }
+
+ adapter->fd = fd;
+ adapter->bus = bus;
+
+ if (ioctl(fd, I2C_FUNCS, &funcs) < 0) {
+ g_printerr("virtio_i2c: failed to get functionality %s: %d\n", path,
+ errno);
+ goto close_fd;
+ }
+
+ if (funcs & I2C_FUNC_I2C) {
+ adapter->smbus = false;
+ } else if (funcs & I2C_FUNC_SMBUS_WORD_DATA) {
Only I2C_FUNC_SMBUS_WORD_DATA is checked here. But in addition to it,
the smbus_xfer
seems support I2C_FUNC_SMBUS_BYTE, I2C_FUNC_SMBUS_BYTE_DATA. So if an
adapter only
support the latter two, it will never go to smbus_xfer.
+ adapter->smbus = true;
+ } else {
+ g_printerr("virtio_i2c: invalid functionality %lx\n", funcs);
+ goto close_fd;
+ }
+
