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Diffstat (limited to 'include/hw/i2c/smbus_slave.h')
| -rw-r--r-- | include/hw/i2c/smbus_slave.h | 100 |
1 files changed, 100 insertions, 0 deletions
diff --git a/include/hw/i2c/smbus_slave.h b/include/hw/i2c/smbus_slave.h new file mode 100644 index 0000000000..ebe068304e --- /dev/null +++ b/include/hw/i2c/smbus_slave.h @@ -0,0 +1,100 @@ +/* + * QEMU SMBus device (slave) API + * + * Copyright (c) 2007 Arastra, Inc. + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ + +#ifndef HW_SMBUS_SLAVE_H +#define HW_SMBUS_SLAVE_H + +#include "hw/i2c/i2c.h" + +#define TYPE_SMBUS_DEVICE "smbus-device" +#define SMBUS_DEVICE(obj) \ + OBJECT_CHECK(SMBusDevice, (obj), TYPE_SMBUS_DEVICE) +#define SMBUS_DEVICE_CLASS(klass) \ + OBJECT_CLASS_CHECK(SMBusDeviceClass, (klass), TYPE_SMBUS_DEVICE) +#define SMBUS_DEVICE_GET_CLASS(obj) \ + OBJECT_GET_CLASS(SMBusDeviceClass, (obj), TYPE_SMBUS_DEVICE) + +typedef struct SMBusDevice SMBusDevice; + +typedef struct SMBusDeviceClass +{ + I2CSlaveClass parent_class; + + /* + * An operation with no data, special in SMBus. + * This may be NULL, quick commands are ignore in that case. + */ + void (*quick_cmd)(SMBusDevice *dev, uint8_t read); + + /* + * We can't distinguish between a word write and a block write with + * length 1, so pass the whole data block including the length byte + * (if present). The device is responsible figuring out what type of + * command this is. + * This may be NULL if no data is written to the device. Writes + * will be ignore in that case. + */ + int (*write_data)(SMBusDevice *dev, uint8_t *buf, uint8_t len); + + /* + * Likewise we can't distinguish between different reads, or even know + * the length of the read until the read is complete, so read data a + * byte at a time. The device is responsible for adding the length + * byte on block reads. This call cannot fail, it should return + * something, preferably 0xff if nothing is available. + * This may be NULL if no data is read from the device. Reads will + * return 0xff in that case. + */ + uint8_t (*receive_byte)(SMBusDevice *dev); +} SMBusDeviceClass; + +#define SMBUS_DATA_MAX_LEN 34 /* command + len + 32 bytes of data. */ + +struct SMBusDevice { + /* The SMBus protocol is implemented on top of I2C. */ + I2CSlave i2c; + + /* Remaining fields for internal use only. */ + int32_t mode; + int32_t data_len; + uint8_t data_buf[SMBUS_DATA_MAX_LEN]; +}; + +extern const VMStateDescription vmstate_smbus_device; + +#define VMSTATE_SMBUS_DEVICE(_field, _state) { \ + .name = (stringify(_field)), \ + .size = sizeof(SMBusDevice), \ + .vmsd = &vmstate_smbus_device, \ + .flags = VMS_STRUCT, \ + .offset = vmstate_offset_value(_state, _field, SMBusDevice), \ +} + +/* + * Users should call this in their .needed functions to know if the + * SMBus slave data needs to be transferred. + */ +bool smbus_vmstate_needed(SMBusDevice *dev); + +#endif |