+static uint64_t sm501_i2c_read(void *opaque, hwaddr addr, unsigned size)
+{
+ SM501State *s = (SM501State *)opaque;
+ uint8_t ret = 0;
+
+ switch (addr) {
+ case SM501_I2C_BYTE_COUNT:
+ ret = s->i2c_byte_count;
+ break;
+ case SM501_I2C_STATUS:
+ ret = s->i2c_status;
+ break;
+ case SM501_I2C_SLAVE_ADDRESS:
+ ret = s->i2c_addr;
+ break;
+ case SM501_I2C_DATA ... SM501_I2C_DATA + 15:
+ ret = s->i2c_data[addr - SM501_I2C_DATA];
+ break;
+ default:
+ qemu_log_mask(LOG_UNIMP, "sm501 i2c : not implemented register read."
+ " addr=0x%" HWADDR_PRIx "\n", addr);
+ }
+
+ SM501_DPRINTF("sm501 i2c regs : read addr=%" HWADDR_PRIx " val=%x\n",
+ addr, ret);
+ return ret;
+}
+
+static void sm501_i2c_write(void *opaque, hwaddr addr, uint64_t value,
+ unsigned size)
+{
+ SM501State *s = (SM501State *)opaque;
+ SM501_DPRINTF("sm501 i2c regs : write addr=%" HWADDR_PRIx
+ " val=%" PRIx64 "\n", addr, value);
+
+ switch (addr) {
+ case SM501_I2C_BYTE_COUNT:
+ s->i2c_byte_count = value & 0xf;
+ break;
+ case SM501_I2C_CONTROL:
+ if (value & SM501_I2C_CONTROL_ENABLE) {
+ if (value & SM501_I2C_CONTROL_START) {
+ int res = i2c_start_transfer(s->i2c_bus,
+ s->i2c_addr >> 1,
+ s->i2c_addr & 1);
+ s->i2c_status |= (res ? SM501_I2C_STATUS_ERROR : 0);
+ if (!res) {
+ int i;
+ SM501_DPRINTF("sm501 i2c : transferring %d bytes to 0x%x\n",
+ s->i2c_byte_count + 1, s->i2c_addr >> 1);
+ for (i = 0; i <= s->i2c_byte_count; i++) {
+ res = i2c_send_recv(s->i2c_bus, &s->i2c_data[i],
+ !(s->i2c_addr & 1));
+ if (res) {
+ SM501_DPRINTF("sm501 i2c : transfer failed"
+ " i=%d, res=%d\n", i, res);
+ s->i2c_status |= SM501_I2C_STATUS_ERROR;
+ return;
+ }
+ }
+ if (i) {
+ SM501_DPRINTF("sm501 i2c : transferred %d bytes\n", i);
+ s->i2c_status = SM501_I2C_STATUS_COMPLETE;
+ }
+ }
+ } else {
+ SM501_DPRINTF("sm501 i2c : end transfer\n");
+ i2c_end_transfer(s->i2c_bus);
+ s->i2c_status &= ~SM501_I2C_STATUS_ERROR;
+ }
+ }
+ break;
+ case SM501_I2C_RESET:
+ if ((value & SM501_I2C_RESET_ERROR) == 0) {
+ s->i2c_status &= ~SM501_I2C_STATUS_ERROR;
+ }
+ break;
+ case SM501_I2C_SLAVE_ADDRESS:
+ s->i2c_addr = value & 0xff;
+ break;
+ case SM501_I2C_DATA ... SM501_I2C_DATA + 15:
+ s->i2c_data[addr - SM501_I2C_DATA] = value & 0xff;
+ break;
+ default:
+ qemu_log_mask(LOG_UNIMP, "sm501 i2c : not implemented register write. "
+ "addr=0x%" HWADDR_PRIx " val=%" PRIx64 "\n", addr, value);
+ }
+}
+
+static const MemoryRegionOps sm501_i2c_ops = {
+ .read = sm501_i2c_read,
+ .write = sm501_i2c_write,
+ .valid = {
+ .min_access_size = 1,
+ .max_access_size = 1,
+ },
+ .impl = {
+ .min_access_size = 1,
+ .max_access_size = 1,
+ },
+ .endianness = DEVICE_LITTLE_ENDIAN,
+};
+