static s32 ali1535_access()

in busses/i2c-ali1535.c [341:463]

• 113 lines of code
• 25 McCabe index (conditional complexity)

static s32 ali1535_access(struct i2c_adapter *adap, u16 addr,
			  unsigned short flags, char read_write, u8 command,
			  int size, union i2c_smbus_data *data)
{
	int i, len;
	int temp;
	int timeout;
	s32 result = 0;

	/* make sure SMBus is idle */
	temp = inb_p(SMBHSTSTS);
	for (timeout = 0;
	     (timeout < MAX_TIMEOUT) && !(temp & ALI1535_STS_IDLE);
	     timeout++) {
		usleep_range(1000, 2000);
		temp = inb_p(SMBHSTSTS);
	}
	if (timeout >= MAX_TIMEOUT)
		dev_warn(&adap->dev, "Idle wait Timeout! STS=0x%02x\n", temp);

	/* clear status register (clear-on-write) */
	outb_p(0xFF, SMBHSTSTS);

	switch (size) {
	case I2C_SMBUS_QUICK:
		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
		       SMBHSTADD);
		size = ALI1535_QUICK;
		outb_p(size, SMBHSTTYP);	/* output command */
		break;
	case I2C_SMBUS_BYTE:
		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
		       SMBHSTADD);
		size = ALI1535_BYTE;
		outb_p(size, SMBHSTTYP);	/* output command */
		if (read_write == I2C_SMBUS_WRITE)
			outb_p(command, SMBHSTCMD);
		break;
	case I2C_SMBUS_BYTE_DATA:
		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
		       SMBHSTADD);
		size = ALI1535_BYTE_DATA;
		outb_p(size, SMBHSTTYP);	/* output command */
		outb_p(command, SMBHSTCMD);
		if (read_write == I2C_SMBUS_WRITE)
			outb_p(data->byte, SMBHSTDAT0);
		break;
	case I2C_SMBUS_WORD_DATA:
		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
		       SMBHSTADD);
		size = ALI1535_WORD_DATA;
		outb_p(size, SMBHSTTYP);	/* output command */
		outb_p(command, SMBHSTCMD);
		if (read_write == I2C_SMBUS_WRITE) {
			outb_p(data->word & 0xff, SMBHSTDAT0);
			outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1);
		}
		break;
	case I2C_SMBUS_BLOCK_DATA:
		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
		       SMBHSTADD);
		size = ALI1535_BLOCK_DATA;
		outb_p(size, SMBHSTTYP);	/* output command */
		outb_p(command, SMBHSTCMD);
		if (read_write == I2C_SMBUS_WRITE) {
			len = data->block[0];
			if (len < 0) {
				len = 0;
				data->block[0] = len;
			}
			if (len > 32) {
				len = 32;
				data->block[0] = len;
			}
			outb_p(len, SMBHSTDAT0);
			/* Reset SMBBLKDAT */
			outb_p(inb_p(SMBHSTTYP) | ALI1535_BLOCK_CLR, SMBHSTTYP);
			for (i = 1; i <= len; i++)
				outb_p(data->block[i], SMBBLKDAT);
		}
		break;
	default:
		dev_warn(&adap->dev, "Unsupported transaction %d\n", size);
		result = -EOPNOTSUPP;
		goto EXIT;
	}

	result = ali1535_transaction(adap);
	if (result)
		goto EXIT;

	if ((read_write == I2C_SMBUS_WRITE) || (size == ALI1535_QUICK)) {
		result = 0;
		goto EXIT;
	}

	switch (size) {
	case ALI1535_BYTE:	/* Result put in SMBHSTDAT0 */
		data->byte = inb_p(SMBHSTDAT0);
		break;
	case ALI1535_BYTE_DATA:
		data->byte = inb_p(SMBHSTDAT0);
		break;
	case ALI1535_WORD_DATA:
		data->word = inb_p(SMBHSTDAT0) + (inb_p(SMBHSTDAT1) << 8);
		break;
	case ALI1535_BLOCK_DATA:
		len = inb_p(SMBHSTDAT0);
		if (len > 32)
			len = 32;
		data->block[0] = len;
		/* Reset SMBBLKDAT */
		outb_p(inb_p(SMBHSTTYP) | ALI1535_BLOCK_CLR, SMBHSTTYP);
		for (i = 1; i <= data->block[0]; i++) {
			data->block[i] = inb_p(SMBBLKDAT);
			dev_dbg(&adap->dev, "Blk: len=%d, i=%d, data=%02x\n",
				len, i, data->block[i]);
		}
		break;
	}
EXIT:
	return result;
}