Hi, thanks for the example patch. > Here is debug log I tested multibyte i2c writes using zl10353 demod. All > returned bytes are not same, but it due to write only register bits I > think. > > dvb_usb_gl861 1-13:1.0: 1 | c0 02 00 1e 50 00 01 00 <<< 03 > dvb_usb_gl861 1-13:1.0: 1 | c0 02 00 1e 51 00 01 00 <<< 44 > dvb_usb_gl861 1-13:1.0: 1 | c0 02 00 1e 52 00 01 00 <<< 46 > dvb_usb_gl861 1-13:1.0: 1 | c0 02 00 1e 53 00 01 00 <<< 15 > dvb_usb_gl861 1-13:1.0: 1 | c0 02 00 1e 54 00 01 00 <<< 0f > dvb_usb_gl861 1-13:1.0: 5 | 40 03 00 1e 50 00 05 00 >>> 0c 77 aa bb cc > dvb_usb_gl861 1-13:1.0: 1 | c0 02 00 1e 50 00 01 00 <<< 0c > dvb_usb_gl861 1-13:1.0: 1 | c0 02 00 1e 51 00 01 00 <<< 77 > dvb_usb_gl861 1-13:1.0: 1 | c0 02 00 1e 52 00 01 00 <<< aa > dvb_usb_gl861 1-13:1.0: 1 | c0 02 00 1e 53 00 01 00 <<< 3b > dvb_usb_gl861 1-13:1.0: 1 | c0 02 00 1e 54 00 01 00 <<< 4c > > > Now if you look your tuner i2c implementation... > > buf[0] = msg->addr << 1; > memcpy(buf + 1, msg->buf, msg->len); > ret = usb_control_msg(d->udev, usb_sndctrlpipe(d->udev, 0), > GL861_REQ_I2C_RAW, GL861_WRITE, > priv->i2c_client_demod->addr << (8 + 1), 0xFE, buf, msg->len + 1, 2000); > > ...it translates same. Log of an 1-byte read from tuner in Friio looks like the following: (re-formatted from my past post: https://patchwork.linuxtv.org/comment/92946/ ) 40 03 00 30 fe 00 01 00 >>> c1 # command a read from the tuner@0x60 (hence 0xc1) c0 02 00 30 00 01 01 00 <<< 7c # get the result (return value: 0x7c) so, - One read is composed of *two* USB messages. (note that friio_tuner_i2c_xfer() does NOT combine the two I2C messages of one read, and issues separate USB message for each, contrary to gl861_i2c_master_xfer()). - The second USB message uses CMD_READ but 'index'(demod register addr) value exceeds 8bit (0x0100), thus cannot use the normal gl861_i2c_master_xfer() as is. It looks to me different. Regards, Akihiro
