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Diffstat (limited to 'net/nfc/nci/spi.c')
-rw-r--r--net/nfc/nci/spi.c239
1 files changed, 91 insertions, 148 deletions
diff --git a/net/nfc/nci/spi.c b/net/nfc/nci/spi.c
index c7cf37ba7298..f1d426f10cce 100644
--- a/net/nfc/nci/spi.c
+++ b/net/nfc/nci/spi.c
@@ -21,11 +21,8 @@
#include <linux/export.h>
#include <linux/spi/spi.h>
#include <linux/crc-ccitt.h>
-#include <linux/nfc.h>
#include <net/nfc/nci_core.h>
-#define NCI_SPI_HDR_LEN 4
-#define NCI_SPI_CRC_LEN 2
#define NCI_SPI_ACK_SHIFT 6
#define NCI_SPI_MSB_PAYLOAD_MASK 0x3F
@@ -41,54 +38,48 @@
#define CRC_INIT 0xFFFF
-static int nci_spi_open(struct nci_dev *nci_dev)
-{
- struct nci_spi_dev *ndev = nci_get_drvdata(nci_dev);
-
- return ndev->ops->open(ndev);
-}
-
-static int nci_spi_close(struct nci_dev *nci_dev)
-{
- struct nci_spi_dev *ndev = nci_get_drvdata(nci_dev);
-
- return ndev->ops->close(ndev);
-}
-
-static int __nci_spi_send(struct nci_spi_dev *ndev, struct sk_buff *skb)
+static int __nci_spi_send(struct nci_spi *nspi, struct sk_buff *skb,
+ int cs_change)
{
struct spi_message m;
struct spi_transfer t;
- t.tx_buf = skb->data;
- t.len = skb->len;
- t.cs_change = 0;
- t.delay_usecs = ndev->xfer_udelay;
+ memset(&t, 0, sizeof(struct spi_transfer));
+ /* a NULL skb means we just want the SPI chip select line to raise */
+ if (skb) {
+ t.tx_buf = skb->data;
+ t.len = skb->len;
+ } else {
+ /* still set tx_buf non NULL to make the driver happy */
+ t.tx_buf = &t;
+ t.len = 0;
+ }
+ t.cs_change = cs_change;
+ t.delay_usecs = nspi->xfer_udelay;
spi_message_init(&m);
spi_message_add_tail(&t, &m);
- return spi_sync(ndev->spi, &m);
+ return spi_sync(nspi->spi, &m);
}
-static int nci_spi_send(struct nci_dev *nci_dev, struct sk_buff *skb)
+int nci_spi_send(struct nci_spi *nspi,
+ struct completion *write_handshake_completion,
+ struct sk_buff *skb)
{
- struct nci_spi_dev *ndev = nci_get_drvdata(nci_dev);
unsigned int payload_len = skb->len;
unsigned char *hdr;
int ret;
long completion_rc;
- ndev->ops->deassert_int(ndev);
-
/* add the NCI SPI header to the start of the buffer */
hdr = skb_push(skb, NCI_SPI_HDR_LEN);
hdr[0] = NCI_SPI_DIRECT_WRITE;
- hdr[1] = ndev->acknowledge_mode;
+ hdr[1] = nspi->acknowledge_mode;
hdr[2] = payload_len >> 8;
hdr[3] = payload_len & 0xFF;
- if (ndev->acknowledge_mode == NCI_SPI_CRC_ENABLED) {
+ if (nspi->acknowledge_mode == NCI_SPI_CRC_ENABLED) {
u16 crc;
crc = crc_ccitt(CRC_INIT, skb->data, skb->len);
@@ -96,123 +87,77 @@ static int nci_spi_send(struct nci_dev *nci_dev, struct sk_buff *skb)
*skb_put(skb, 1) = crc & 0xFF;
}
- ret = __nci_spi_send(ndev, skb);
+ if (write_handshake_completion) {
+ /* Trick SPI driver to raise chip select */
+ ret = __nci_spi_send(nspi, NULL, 1);
+ if (ret)
+ goto done;
- kfree_skb(skb);
- ndev->ops->assert_int(ndev);
+ /* wait for NFC chip hardware handshake to complete */
+ if (wait_for_completion_timeout(write_handshake_completion,
+ msecs_to_jiffies(1000)) == 0) {
+ ret = -ETIME;
+ goto done;
+ }
+ }
- if (ret != 0 || ndev->acknowledge_mode == NCI_SPI_CRC_DISABLED)
+ ret = __nci_spi_send(nspi, skb, 0);
+ if (ret != 0 || nspi->acknowledge_mode == NCI_SPI_CRC_DISABLED)
goto done;
- init_completion(&ndev->req_completion);
- completion_rc =
- wait_for_completion_interruptible_timeout(&ndev->req_completion,
- NCI_SPI_SEND_TIMEOUT);
+ init_completion(&nspi->req_completion);
+ completion_rc = wait_for_completion_interruptible_timeout(
+ &nspi->req_completion,
+ NCI_SPI_SEND_TIMEOUT);
- if (completion_rc <= 0 || ndev->req_result == ACKNOWLEDGE_NACK)
+ if (completion_rc <= 0 || nspi->req_result == ACKNOWLEDGE_NACK)
ret = -EIO;
done:
+ kfree_skb(skb);
+
return ret;
}
-
-static struct nci_ops nci_spi_ops = {
- .open = nci_spi_open,
- .close = nci_spi_close,
- .send = nci_spi_send,
-};
+EXPORT_SYMBOL_GPL(nci_spi_send);
/* ---- Interface to NCI SPI drivers ---- */
/**
- * nci_spi_allocate_device - allocate a new nci spi device
+ * nci_spi_allocate_spi - allocate a new nci spi
*
* @spi: SPI device
- * @ops: device operations
- * @supported_protocols: NFC protocols supported by the device
- * @supported_se: NFC Secure Elements supported by the device
- * @acknowledge_mode: Acknowledge mode used by the device
+ * @acknowledge_mode: Acknowledge mode used by the NFC device
* @delay: delay between transactions in us
+ * @ndev: nci dev to send incoming nci frames to
*/
-struct nci_spi_dev *nci_spi_allocate_device(struct spi_device *spi,
- struct nci_spi_ops *ops,
- u32 supported_protocols,
- u32 supported_se,
- u8 acknowledge_mode,
- unsigned int delay)
+struct nci_spi *nci_spi_allocate_spi(struct spi_device *spi,
+ u8 acknowledge_mode, unsigned int delay,
+ struct nci_dev *ndev)
{
- struct nci_spi_dev *ndev;
- int tailroom = 0;
+ struct nci_spi *nspi;
- if (!ops->open || !ops->close || !ops->assert_int || !ops->deassert_int)
+ nspi = devm_kzalloc(&spi->dev, sizeof(struct nci_spi), GFP_KERNEL);
+ if (!nspi)
return NULL;
- if (!supported_protocols)
- return NULL;
-
- ndev = devm_kzalloc(&spi->dev, sizeof(struct nci_dev), GFP_KERNEL);
- if (!ndev)
- return NULL;
+ nspi->acknowledge_mode = acknowledge_mode;
+ nspi->xfer_udelay = delay;
- ndev->ops = ops;
- ndev->acknowledge_mode = acknowledge_mode;
- ndev->xfer_udelay = delay;
+ nspi->spi = spi;
+ nspi->ndev = ndev;
- if (acknowledge_mode == NCI_SPI_CRC_ENABLED)
- tailroom += NCI_SPI_CRC_LEN;
-
- ndev->nci_dev = nci_allocate_device(&nci_spi_ops, supported_protocols,
- NCI_SPI_HDR_LEN, tailroom);
- if (!ndev->nci_dev)
- return NULL;
-
- nci_set_drvdata(ndev->nci_dev, ndev);
-
- return ndev;
+ return nspi;
}
-EXPORT_SYMBOL_GPL(nci_spi_allocate_device);
+EXPORT_SYMBOL_GPL(nci_spi_allocate_spi);
-/**
- * nci_spi_free_device - deallocate nci spi device
- *
- * @ndev: The nci spi device to deallocate
- */
-void nci_spi_free_device(struct nci_spi_dev *ndev)
-{
- nci_free_device(ndev->nci_dev);
-}
-EXPORT_SYMBOL_GPL(nci_spi_free_device);
-
-/**
- * nci_spi_register_device - register a nci spi device in the nfc subsystem
- *
- * @pdev: The nci spi device to register
- */
-int nci_spi_register_device(struct nci_spi_dev *ndev)
-{
- return nci_register_device(ndev->nci_dev);
-}
-EXPORT_SYMBOL_GPL(nci_spi_register_device);
-
-/**
- * nci_spi_unregister_device - unregister a nci spi device in the nfc subsystem
- *
- * @dev: The nci spi device to unregister
- */
-void nci_spi_unregister_device(struct nci_spi_dev *ndev)
-{
- nci_unregister_device(ndev->nci_dev);
-}
-EXPORT_SYMBOL_GPL(nci_spi_unregister_device);
-
-static int send_acknowledge(struct nci_spi_dev *ndev, u8 acknowledge)
+static int send_acknowledge(struct nci_spi *nspi, u8 acknowledge)
{
struct sk_buff *skb;
unsigned char *hdr;
u16 crc;
int ret;
- skb = nci_skb_alloc(ndev->nci_dev, 0, GFP_KERNEL);
+ skb = nci_skb_alloc(nspi->ndev, 0, GFP_KERNEL);
/* add the NCI SPI header to the start of the buffer */
hdr = skb_push(skb, NCI_SPI_HDR_LEN);
@@ -225,14 +170,14 @@ static int send_acknowledge(struct nci_spi_dev *ndev, u8 acknowledge)
*skb_put(skb, 1) = crc >> 8;
*skb_put(skb, 1) = crc & 0xFF;
- ret = __nci_spi_send(ndev, skb);
+ ret = __nci_spi_send(nspi, skb, 0);
kfree_skb(skb);
return ret;
}
-static struct sk_buff *__nci_spi_recv_frame(struct nci_spi_dev *ndev)
+static struct sk_buff *__nci_spi_read(struct nci_spi *nspi)
{
struct sk_buff *skb;
struct spi_message m;
@@ -242,43 +187,49 @@ static struct sk_buff *__nci_spi_recv_frame(struct nci_spi_dev *ndev)
int ret;
spi_message_init(&m);
+
+ memset(&tx, 0, sizeof(struct spi_transfer));
req[0] = NCI_SPI_DIRECT_READ;
- req[1] = ndev->acknowledge_mode;
+ req[1] = nspi->acknowledge_mode;
tx.tx_buf = req;
tx.len = 2;
tx.cs_change = 0;
spi_message_add_tail(&tx, &m);
+
+ memset(&rx, 0, sizeof(struct spi_transfer));
rx.rx_buf = resp_hdr;
rx.len = 2;
rx.cs_change = 1;
spi_message_add_tail(&rx, &m);
- ret = spi_sync(ndev->spi, &m);
+ ret = spi_sync(nspi->spi, &m);
if (ret)
return NULL;
- if (ndev->acknowledge_mode == NCI_SPI_CRC_ENABLED)
+ if (nspi->acknowledge_mode == NCI_SPI_CRC_ENABLED)
rx_len = ((resp_hdr[0] & NCI_SPI_MSB_PAYLOAD_MASK) << 8) +
resp_hdr[1] + NCI_SPI_CRC_LEN;
else
rx_len = (resp_hdr[0] << 8) | resp_hdr[1];
- skb = nci_skb_alloc(ndev->nci_dev, rx_len, GFP_KERNEL);
+ skb = nci_skb_alloc(nspi->ndev, rx_len, GFP_KERNEL);
if (!skb)
return NULL;
spi_message_init(&m);
+
+ memset(&rx, 0, sizeof(struct spi_transfer));
rx.rx_buf = skb_put(skb, rx_len);
rx.len = rx_len;
rx.cs_change = 0;
- rx.delay_usecs = ndev->xfer_udelay;
+ rx.delay_usecs = nspi->xfer_udelay;
spi_message_add_tail(&rx, &m);
- ret = spi_sync(ndev->spi, &m);
+ ret = spi_sync(nspi->spi, &m);
if (ret)
goto receive_error;
- if (ndev->acknowledge_mode == NCI_SPI_CRC_ENABLED) {
+ if (nspi->acknowledge_mode == NCI_SPI_CRC_ENABLED) {
*skb_push(skb, 1) = resp_hdr[1];
*skb_push(skb, 1) = resp_hdr[0];
}
@@ -318,61 +269,53 @@ static u8 nci_spi_get_ack(struct sk_buff *skb)
}
/**
- * nci_spi_recv_frame - receive frame from NCI SPI drivers
+ * nci_spi_read - read frame from NCI SPI drivers
*
- * @ndev: The nci spi device
+ * @nspi: The nci spi
* Context: can sleep
*
* This call may only be used from a context that may sleep. The sleep
* is non-interruptible, and has no timeout.
*
- * It returns zero on success, else a negative error code.
+ * It returns an allocated skb containing the frame on success, or NULL.
*/
-int nci_spi_recv_frame(struct nci_spi_dev *ndev)
+struct sk_buff *nci_spi_read(struct nci_spi *nspi)
{
struct sk_buff *skb;
- int ret = 0;
-
- ndev->ops->deassert_int(ndev);
/* Retrieve frame from SPI */
- skb = __nci_spi_recv_frame(ndev);
- if (!skb) {
- ret = -EIO;
+ skb = __nci_spi_read(nspi);
+ if (!skb)
goto done;
- }
- if (ndev->acknowledge_mode == NCI_SPI_CRC_ENABLED) {
+ if (nspi->acknowledge_mode == NCI_SPI_CRC_ENABLED) {
if (!nci_spi_check_crc(skb)) {
- send_acknowledge(ndev, ACKNOWLEDGE_NACK);
+ send_acknowledge(nspi, ACKNOWLEDGE_NACK);
goto done;
}
/* In case of acknowledged mode: if ACK or NACK received,
* unblock completion of latest frame sent.
*/
- ndev->req_result = nci_spi_get_ack(skb);
- if (ndev->req_result)
- complete(&ndev->req_completion);
+ nspi->req_result = nci_spi_get_ack(skb);
+ if (nspi->req_result)
+ complete(&nspi->req_completion);
}
/* If there is no payload (ACK/NACK only frame),
* free the socket buffer
*/
- if (skb->len == 0) {
+ if (!skb->len) {
kfree_skb(skb);
+ skb = NULL;
goto done;
}
- if (ndev->acknowledge_mode == NCI_SPI_CRC_ENABLED)
- send_acknowledge(ndev, ACKNOWLEDGE_ACK);
-
- /* Forward skb to NCI core layer */
- ret = nci_recv_frame(ndev->nci_dev, skb);
+ if (nspi->acknowledge_mode == NCI_SPI_CRC_ENABLED)
+ send_acknowledge(nspi, ACKNOWLEDGE_ACK);
done:
- ndev->ops->assert_int(ndev);
- return ret;
+ return skb;
}
-EXPORT_SYMBOL_GPL(nci_spi_recv_frame);
+EXPORT_SYMBOL_GPL(nci_spi_read);