Hi Daniel, It is not supposed to use difrac[0] all the time. I agree that the code is ambiguous and should be written in the form that you have suggested. Best regards, Mark -----Original Message----- From: Daniel Glöckner [mailto:dg@xxxxxxxxx] Sent: 06 January 2011 23:47 To: Mark Adamson Cc: linux-usb@xxxxxxxxxxxxxxx Subject: ftdi_sio FT2232H baud rate calculations Hi, these calculations done in ftdi_2232h_baud_base_to_divisor look suspicious to me: /* hi-speed baud rate is 10-bit sampling instead of 16-bit */ divisor3 = (base / 10 / baud) * 8; divisor = divisor3 >> 3; divisor |= (__u32)divfrac[divisor3 & 0x7] << 14; Is it supposed to always use divfrac[0] (== 0)? If not, I'd write divisor3 = base * 8 / (baud * 10); instead. Daniel -- Dipl.-Math. Daniel Glöckner, emlix GmbH, http://www.emlix.com Fon +49 551 30664-0, Fax -11, Bahnhofsallee 1b, 37081 Göttingen, Germany Sitz der Gesellschaft: Göttingen, Amtsgericht Göttingen HR B 3160 Geschäftsführung: Dr. Uwe Kracke, Ust-IdNr.: DE 205 198 055 emlix - your embedded linux partner -- This message has been scanned for viruses and dangerous content by Alchemist CleanFeed, and is believed to be clean. -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
