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> =20 > - cec_write(cec, TEGRA_CEC_HW_CONTROL, TEGRA_CEC_HWCTRL_TX_RX_MODE); > + /* > + * TX_NAK_MODE ensures that the whole message is transmitted even > + * if each byte is NACKed. Without this flag the retransmit of the > + * messages after a NACK can be corrupt. This is a bug in the hardware. > + * > + * While less efficient, in practice you rarely transmit messages > + * that can be NACKed, with the exception of POLL messages which > + * are just one byte anyway. > + */ > + cec_write(cec, TEGRA_CEC_HW_CONTROL, > + TEGRA_CEC_HWCTRL_TX_RX_MODE | > + TEGRA_CEC_HWCTRL_TX_NAK_MODE); > return 0; > } > =20 > --=20 > 2.53.0 >=20 >=20 Reviewed-by: Mikko Perttunen