static s32 amd8111_access()

in busses/i2c-amd8111.c [189:397]

• 189 lines of code
• 60 McCabe index (conditional complexity)

static s32 amd8111_access(struct i2c_adapter *adap, u16 addr,
		unsigned short flags, char read_write, u8 command, int size,
		union i2c_smbus_data *data)
{
	struct amd_smbus *smbus = adap->algo_data;
	unsigned char protocol, len, pec, temp[2];
	int i, status;

	protocol = (read_write == I2C_SMBUS_READ) ? AMD_SMB_PRTCL_READ
						  : AMD_SMB_PRTCL_WRITE;
	pec = (flags & I2C_CLIENT_PEC) ? AMD_SMB_PRTCL_PEC : 0;

	switch (size) {
	case I2C_SMBUS_QUICK:
		protocol |= AMD_SMB_PRTCL_QUICK;
		read_write = I2C_SMBUS_WRITE;
		break;

	case I2C_SMBUS_BYTE:
		if (read_write == I2C_SMBUS_WRITE) {
			status = amd_ec_write(smbus, AMD_SMB_CMD,
						command);
			if (status)
				return status;
		}
		protocol |= AMD_SMB_PRTCL_BYTE;
		break;

	case I2C_SMBUS_BYTE_DATA:
		status = amd_ec_write(smbus, AMD_SMB_CMD, command);
		if (status)
			return status;
		if (read_write == I2C_SMBUS_WRITE) {
			status = amd_ec_write(smbus, AMD_SMB_DATA,
						data->byte);
			if (status)
				return status;
		}
		protocol |= AMD_SMB_PRTCL_BYTE_DATA;
		break;

	case I2C_SMBUS_WORD_DATA:
		status = amd_ec_write(smbus, AMD_SMB_CMD, command);
		if (status)
			return status;
		if (read_write == I2C_SMBUS_WRITE) {
			status = amd_ec_write(smbus, AMD_SMB_DATA,
						data->word & 0xff);
			if (status)
				return status;
			status = amd_ec_write(smbus, AMD_SMB_DATA + 1,
						data->word >> 8);
			if (status)
				return status;
		}
		protocol |= AMD_SMB_PRTCL_WORD_DATA | pec;
		break;

	case I2C_SMBUS_BLOCK_DATA:
		status = amd_ec_write(smbus, AMD_SMB_CMD, command);
		if (status)
			return status;
		if (read_write == I2C_SMBUS_WRITE) {
			len = min_t(u8, data->block[0],
					I2C_SMBUS_BLOCK_MAX);
			status = amd_ec_write(smbus, AMD_SMB_BCNT, len);
			if (status)
				return status;
			for (i = 0; i < len; i++) {
				status =
					amd_ec_write(smbus, AMD_SMB_DATA + i,
						data->block[i + 1]);
				if (status)
					return status;
			}
		}
		protocol |= AMD_SMB_PRTCL_BLOCK_DATA | pec;
		break;

	case I2C_SMBUS_I2C_BLOCK_DATA:
		len = min_t(u8, data->block[0],
				I2C_SMBUS_BLOCK_MAX);
		status = amd_ec_write(smbus, AMD_SMB_CMD, command);
		if (status)
			return status;
		status = amd_ec_write(smbus, AMD_SMB_BCNT, len);
		if (status)
			return status;
		if (read_write == I2C_SMBUS_WRITE)
			for (i = 0; i < len; i++) {
				status =
					amd_ec_write(smbus, AMD_SMB_DATA + i,
						data->block[i + 1]);
				if (status)
					return status;
			}
		protocol |= AMD_SMB_PRTCL_I2C_BLOCK_DATA;
		break;

	case I2C_SMBUS_PROC_CALL:
		status = amd_ec_write(smbus, AMD_SMB_CMD, command);
		if (status)
			return status;
		status = amd_ec_write(smbus, AMD_SMB_DATA,
					data->word & 0xff);
		if (status)
			return status;
		status = amd_ec_write(smbus, AMD_SMB_DATA + 1,
					data->word >> 8);
		if (status)
			return status;
		protocol = AMD_SMB_PRTCL_PROC_CALL | pec;
		read_write = I2C_SMBUS_READ;
		break;

	case I2C_SMBUS_BLOCK_PROC_CALL:
		len = min_t(u8, data->block[0],
				I2C_SMBUS_BLOCK_MAX - 1);
		status = amd_ec_write(smbus, AMD_SMB_CMD, command);
		if (status)
			return status;
		status = amd_ec_write(smbus, AMD_SMB_BCNT, len);
		if (status)
			return status;
		for (i = 0; i < len; i++) {
			status = amd_ec_write(smbus, AMD_SMB_DATA + i,
						data->block[i + 1]);
			if (status)
				return status;
		}
		protocol = AMD_SMB_PRTCL_BLOCK_PROC_CALL | pec;
		read_write = I2C_SMBUS_READ;
		break;

	default:
		dev_warn(&adap->dev, "Unsupported transaction %d\n", size);
		return -EOPNOTSUPP;
	}

	status = amd_ec_write(smbus, AMD_SMB_ADDR, addr << 1);
	if (status)
		return status;
	status = amd_ec_write(smbus, AMD_SMB_PRTCL, protocol);
	if (status)
		return status;

	status = amd_ec_read(smbus, AMD_SMB_STS, temp + 0);
	if (status)
		return status;

	if (~temp[0] & AMD_SMB_STS_DONE) {
		udelay(500);
		status = amd_ec_read(smbus, AMD_SMB_STS, temp + 0);
		if (status)
			return status;
	}

	if (~temp[0] & AMD_SMB_STS_DONE) {
		msleep(1);
		status = amd_ec_read(smbus, AMD_SMB_STS, temp + 0);
		if (status)
			return status;
	}

	if ((~temp[0] & AMD_SMB_STS_DONE) || (temp[0] & AMD_SMB_STS_STATUS))
		return -EIO;

	if (read_write == I2C_SMBUS_WRITE)
		return 0;

	switch (size) {
	case I2C_SMBUS_BYTE:
	case I2C_SMBUS_BYTE_DATA:
		status = amd_ec_read(smbus, AMD_SMB_DATA, &data->byte);
		if (status)
			return status;
		break;

	case I2C_SMBUS_WORD_DATA:
	case I2C_SMBUS_PROC_CALL:
		status = amd_ec_read(smbus, AMD_SMB_DATA, temp + 0);
		if (status)
			return status;
		status = amd_ec_read(smbus, AMD_SMB_DATA + 1, temp + 1);
		if (status)
			return status;
		data->word = (temp[1] << 8) | temp[0];
		break;

	case I2C_SMBUS_BLOCK_DATA:
	case I2C_SMBUS_BLOCK_PROC_CALL:
		status = amd_ec_read(smbus, AMD_SMB_BCNT, &len);
		if (status)
			return status;
		len = min_t(u8, len, I2C_SMBUS_BLOCK_MAX);
		fallthrough;
	case I2C_SMBUS_I2C_BLOCK_DATA:
		for (i = 0; i < len; i++) {
			status = amd_ec_read(smbus, AMD_SMB_DATA + i,
						data->block + i + 1);
			if (status)
				return status;
		}
		data->block[0] = len;
		break;
	}

	return 0;
}