Re: [Qemu-devel] [PATCH 2/3] i2c: Add an SMBus vmstate structure

[Peter Maydell <peter.maydell@linaro.org>]

On 8 November 2018 at 14:23, Philippe Mathieu-Daudé <philmd@redhat.com> wrote:
> Hi Corey,
>
>
> On 7/11/18 16:54, minyard@acm.org wrote:
>>
>> From: Corey Minyard <cminyard@mvista.com>
>>
>> There is no vmstate handling for SMBus, so no device sitting on SMBus
>> can have a state transfer that works reliable.  So add it.
>>
>> Signed-off-by: Corey Minyard <cminyard@mvista.com>
>> Cc: Paolo Bonzini <pbonzini@redhat.com>
>> Cc: Michael S. Tsirkin <mst@redhat.com>
>> Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
>> ---
>>   hw/i2c/smbus.c         | 14 ++++++++++++++
>>   include/hw/i2c/smbus.h | 18 +++++++++++++++---
>>   2 files changed, 29 insertions(+), 3 deletions(-)
>>
>> diff --git a/hw/i2c/smbus.c b/hw/i2c/smbus.c
>> index 6ff77c582f..b0774d7683 100644
>> --- a/hw/i2c/smbus.c
>> +++ b/hw/i2c/smbus.c
>> @@ -349,6 +349,20 @@ int smbus_write_block(I2CBus *bus, uint8_t addr,
>> uint8_t command, uint8_t *data,
>>       return 0;
>>   }
>>   +const VMStateDescription vmstate_smbus_device = {
>> +    .name = TYPE_SMBUS_DEVICE,
>> +    .version_id = 1,
>> +    .minimum_version_id = 1,
>> +    .fields      = (VMStateField[]) {
>> +        VMSTATE_I2C_SLAVE(i2c, SMBusDevice),
>> +        VMSTATE_INT32(mode, SMBusDevice),
>> +        VMSTATE_INT32(data_len, SMBusDevice),
>> +        VMSTATE_UINT8_ARRAY(data_buf, SMBusDevice, SMBUS_DATA_MAX_LEN),
>> +        VMSTATE_UINT8(command, SMBusDevice),
>> +        VMSTATE_END_OF_LIST()
>> +    }
>> +};
>> +
>>   static void smbus_device_class_init(ObjectClass *klass, void *data)
>>   {
>>       I2CSlaveClass *sc = I2C_SLAVE_CLASS(klass);
>> diff --git a/include/hw/i2c/smbus.h b/include/hw/i2c/smbus.h
>> index d8b1b9ee81..7b52020121 100644
>> --- a/include/hw/i2c/smbus.h
>> +++ b/include/hw/i2c/smbus.h
>> @@ -53,14 +53,16 @@ typedef struct SMBusDeviceClass
>>       uint8_t (*read_data)(SMBusDevice *dev, uint8_t cmd, int n);
>>   } 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.  */
>> -    int mode;
>> -    int data_len;
>> -    uint8_t data_buf[34]; /* command + len + 32 bytes of data.  */
>> +    int32_t mode;
>> +    int32_t data_len;
>> +    uint8_t data_buf[SMBUS_DATA_MAX_LEN];
>
>
> Those changes are not in your commit description.
> Can you include them in a separate patch?

These are just the standard "promote types in the state struct
to fixed-width ones required by the VMSTATE macros", aren't
they? I think they're fine as part of the vmstate conversion.

thanks
-- PMM