summaryrefslogtreecommitdiffstats
path: root/drivers/nfc
diff options
context:
space:
mode:
authorMark A. Greer <mgreer@animalcreek.com>2014-09-02 15:12:44 -0700
committerSamuel Ortiz <sameo@linux.intel.com>2014-09-07 23:13:45 +0200
commit1961843ceeca0d3e55744bba7ae8d9e23d04cf6a (patch)
treed515e99992c63e9063d613fabd6375ef6ac28f15 /drivers/nfc
parent6fb9edcb43d0b1bf0ac2aaf6ba488d105c45f477 (diff)
downloadop-kernel-dev-1961843ceeca0d3e55744bba7ae8d9e23d04cf6a.zip
op-kernel-dev-1961843ceeca0d3e55744bba7ae8d9e23d04cf6a.tar.gz
NFC: trf7970a: Handle timeout values of zero
The digital layer can try to send a command with a timeout value of zero (e.g., digital_tg_send_psl_res(). The zero value is used as a flag to indicate that the driver should not expect a response. To handle this, the driver sets an internal timer because it should still get an interrupt with the TX bit set in the IRQ Status Register. When it gets that interrupt, it returns a return value of '0'. If it doesn't get the interrupt before timing out, it returns ETIMEDOUT as usual. Signed-off-by: Mark A. Greer <mgreer@animalcreek.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Diffstat (limited to 'drivers/nfc')
-rw-r--r--drivers/nfc/trf7970a.c29
1 files changed, 22 insertions, 7 deletions
diff --git a/drivers/nfc/trf7970a.c b/drivers/nfc/trf7970a.c
index 00fb2ce..8b109e1 100644
--- a/drivers/nfc/trf7970a.c
+++ b/drivers/nfc/trf7970a.c
@@ -132,6 +132,7 @@
/* TX length is 3 nibbles long ==> 4KB - 1 bytes max */
#define TRF7970A_TX_MAX (4096 - 1)
+#define TRF7970A_WAIT_FOR_TX_IRQ 20
#define TRF7970A_WAIT_FOR_RX_DATA_TIMEOUT 20
#define TRF7970A_WAIT_FOR_FIFO_DRAIN_TIMEOUT 20
#define TRF7970A_WAIT_TO_ISSUE_ISO15693_EOF 40
@@ -555,7 +556,11 @@ static int trf7970a_transmit(struct trf7970a *trf, struct sk_buff *skb,
timeout = TRF7970A_WAIT_TO_ISSUE_ISO15693_EOF;
} else {
trf->state = TRF7970A_ST_WAIT_FOR_RX_DATA;
- timeout = trf->timeout;
+
+ if (!trf->timeout)
+ timeout = TRF7970A_WAIT_FOR_TX_IRQ;
+ else
+ timeout = trf->timeout;
}
}
@@ -754,6 +759,14 @@ static irqreturn_t trf7970a_irq(int irq, void *dev_id)
trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
} else if (status == TRF7970A_IRQ_STATUS_TX) {
trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
+
+ if (!trf->timeout) {
+ trf->ignore_timeout = !cancel_delayed_work(
+ &trf->timeout_work);
+ trf->rx_skb = ERR_PTR(0);
+ trf7970a_send_upstream(trf);
+ break;
+ }
} else {
trf7970a_send_err_upstream(trf, -EIO);
}
@@ -1253,12 +1266,14 @@ static int trf7970a_in_send_cmd(struct nfc_digital_dev *ddev,
goto out_err;
}
- trf->rx_skb = nfc_alloc_recv_skb(TRF7970A_RX_SKB_ALLOC_SIZE,
- GFP_KERNEL);
- if (!trf->rx_skb) {
- dev_dbg(trf->dev, "Can't alloc rx_skb\n");
- ret = -ENOMEM;
- goto out_err;
+ if (timeout) {
+ trf->rx_skb = nfc_alloc_recv_skb(TRF7970A_RX_SKB_ALLOC_SIZE,
+ GFP_KERNEL);
+ if (!trf->rx_skb) {
+ dev_dbg(trf->dev, "Can't alloc rx_skb\n");
+ ret = -ENOMEM;
+ goto out_err;
+ }
}
if (trf->state == TRF7970A_ST_IDLE_RX_BLOCKED) {
OpenPOWER on IntegriCloud