diff options
Diffstat (limited to 'drivers/nfc')
| -rw-r--r-- | drivers/nfc/trf7970a.c | 25 |
1 files changed, 19 insertions, 6 deletions
diff --git a/drivers/nfc/trf7970a.c b/drivers/nfc/trf7970a.c index a2e0a21d6ea2..d17d424bdcee 100644 --- a/drivers/nfc/trf7970a.c +++ b/drivers/nfc/trf7970a.c @@ -337,6 +337,7 @@ struct trf7970a { nfc_digital_cmd_complete_t cb; void *cb_arg; u8 iso_ctrl; + u8 iso_ctrl_tech; u8 special_fcn_reg1; int technology; int framing; @@ -787,6 +788,7 @@ static int trf7970a_init(struct trf7970a *trf) if (ret) goto err_out; + trf->iso_ctrl = 0xff; return 0; err_out: @@ -889,10 +891,10 @@ static int trf7970a_config_rf_tech(struct trf7970a *trf, int tech) switch (tech) { case NFC_DIGITAL_RF_TECH_106A: - trf->iso_ctrl = TRF7970A_ISO_CTRL_14443A_106; + trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_14443A_106; break; case NFC_DIGITAL_RF_TECH_ISO15693: - trf->iso_ctrl = TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648; + trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648; break; default: dev_dbg(trf->dev, "Unsupported rf technology: %d\n", tech); @@ -906,24 +908,27 @@ static int trf7970a_config_rf_tech(struct trf7970a *trf, int tech) static int trf7970a_config_framing(struct trf7970a *trf, int framing) { + u8 iso_ctrl = trf->iso_ctrl_tech; + int ret; + dev_dbg(trf->dev, "framing: %d\n", framing); switch (framing) { case NFC_DIGITAL_FRAMING_NFCA_SHORT: case NFC_DIGITAL_FRAMING_NFCA_STANDARD: trf->tx_cmd = TRF7970A_CMD_TRANSMIT_NO_CRC; - trf->iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N; + iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N; break; case NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A: case NFC_DIGITAL_FRAMING_NFCA_T4T: case NFC_DIGITAL_FRAMING_ISO15693_INVENTORY: case NFC_DIGITAL_FRAMING_ISO15693_T5T: trf->tx_cmd = TRF7970A_CMD_TRANSMIT; - trf->iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N; + iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N; break; case NFC_DIGITAL_FRAMING_NFCA_T2T: trf->tx_cmd = TRF7970A_CMD_TRANSMIT; - trf->iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N; + iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N; break; default: dev_dbg(trf->dev, "Unsupported Framing: %d\n", framing); @@ -932,7 +937,15 @@ static int trf7970a_config_framing(struct trf7970a *trf, int framing) trf->framing = framing; - return trf7970a_write(trf, TRF7970A_ISO_CTRL, trf->iso_ctrl); + if (iso_ctrl != trf->iso_ctrl) { + ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, iso_ctrl); + if (ret) + return ret; + + trf->iso_ctrl = iso_ctrl; + } + + return 0; } static int trf7970a_in_configure_hw(struct nfc_digital_dev *ddev, int type, |