From a81d1ab3cad77e20c2df8baef0a35a4980fc511c Mon Sep 17 00:00:00 2001 From: Mark Greer Date: Thu, 15 Jun 2017 10:46:17 -0700 Subject: [PATCH] Revert "NFC: trf7970a: Handle extra byte in response to Type 5 RMB commands" This reverts commit ab714817d7e891608d31f6996b1e4c43cf2bf342. The original commit was designed to handle a bug in the trf7970a NFC controller where an extra byte was returned in Read Multiple Blocks (RMB) command responses. However, it has become less clear whether it is a bug in the trf7970a or in the tag. In addition, it was assumed that the extra byte was always returned but it turns out that is not always the case. The result is that a byte of good data is trimmed off when the extra byte is not present ultimately causing the neard deamon to fail the read. Since the trf7970a driver does not have the context to know when to trim the byte or not, remove the code from the trf7970a driver all together (and move it up to the neard daemon). This has the added benefit of simplifying the kernel driver and putting the extra complexity into userspace. CC: Rob Herring CC: devicetree@vger.kernel.org Signed-off-by: Mark Greer Signed-off-by: Samuel Ortiz --- .../devicetree/bindings/net/nfc/trf7970a.txt | 4 ---- drivers/nfc/trf7970a.c | 25 ++++------------------ 2 files changed, 4 insertions(+), 25 deletions(-) diff --git a/Documentation/devicetree/bindings/net/nfc/trf7970a.txt b/Documentation/devicetree/bindings/net/nfc/trf7970a.txt index a24a93a..60c833d6 100644 --- a/Documentation/devicetree/bindings/net/nfc/trf7970a.txt +++ b/Documentation/devicetree/bindings/net/nfc/trf7970a.txt @@ -17,9 +17,6 @@ Optional SoC Specific Properties: "IRQ Status Read" erratum. - en2-rf-quirk: Specify that the trf7970a being used has the "EN2 RF" erratum. -- t5t-rmb-extra-byte-quirk: Specify that the trf7970a has the erratum - where an extra byte is returned by Read Multiple Block commands issued - to Type 5 tags. - vdd-io-supply: Regulator specifying voltage for vdd-io - clock-frequency: Set to specify that the input frequency to the trf7970a is 13560000Hz or 27120000Hz @@ -43,7 +40,6 @@ Example (for ARM-based BeagleBone with TRF7970A on SPI1): autosuspend-delay = <30000>; irq-status-read-quirk; en2-rf-quirk; - t5t-rmb-extra-byte-quirk; clock-frequency = <27120000>; status = "okay"; }; diff --git a/drivers/nfc/trf7970a.c b/drivers/nfc/trf7970a.c index 914463a..6ee7b03 100644 --- a/drivers/nfc/trf7970a.c +++ b/drivers/nfc/trf7970a.c @@ -150,7 +150,6 @@ */ #define TRF7970A_QUIRK_IRQ_STATUS_READ BIT(0) #define TRF7970A_QUIRK_EN2_MUST_STAY_LOW BIT(1) -#define TRF7970A_QUIRK_T5T_RMB_EXTRA_BYTE BIT(2) /* Direct commands */ #define TRF7970A_CMD_IDLE 0x00 @@ -449,7 +448,6 @@ struct trf7970a { u8 md_rf_tech; u8 tx_cmd; bool issue_eof; - bool adjust_resp_len; struct gpio_desc *en_gpiod; struct gpio_desc *en2_gpiod; struct mutex lock; @@ -630,13 +628,6 @@ static void trf7970a_send_upstream(struct trf7970a *trf) trf->aborting = false; } - if (trf->adjust_resp_len) { - if (trf->rx_skb) - skb_trim(trf->rx_skb, trf->rx_skb->len - 1); - - trf->adjust_resp_len = false; - } - trf->cb(trf->ddev, trf->cb_arg, trf->rx_skb); trf->rx_skb = NULL; @@ -1459,15 +1450,10 @@ static int trf7970a_per_cmd_config(struct trf7970a *trf, struct sk_buff *skb) trf->iso_ctrl = iso_ctrl; } - if (trf->framing == NFC_DIGITAL_FRAMING_ISO15693_T5T) { - if (trf7970a_is_iso15693_write_or_lock(req[1]) && - (req[0] & ISO15693_REQ_FLAG_OPTION)) - trf->issue_eof = true; - else if ((trf->quirks & - TRF7970A_QUIRK_T5T_RMB_EXTRA_BYTE) && - (req[1] == ISO15693_CMD_READ_MULTIPLE_BLOCK)) - trf->adjust_resp_len = true; - } + if ((trf->framing == NFC_DIGITAL_FRAMING_ISO15693_T5T) && + trf7970a_is_iso15693_write_or_lock(req[1]) && + (req[0] & ISO15693_REQ_FLAG_OPTION)) + trf->issue_eof = true; } return 0; @@ -2032,9 +2018,6 @@ static int trf7970a_probe(struct spi_device *spi) return ret; } - if (of_property_read_bool(np, "t5t-rmb-extra-byte-quirk")) - trf->quirks |= TRF7970A_QUIRK_T5T_RMB_EXTRA_BYTE; - if (of_property_read_bool(np, "irq-status-read-quirk")) trf->quirks |= TRF7970A_QUIRK_IRQ_STATUS_READ; -- 2.7.4