[PATCH] NFC: added the sysfs entry for nfcsim workqueue delay

From: Saurabh Sengar
Date: Fri Nov 13 2015 - 06:19:19 EST


added the sysfs entry for nfcsim workqueue delay, as tx_delay

Signed-off-by: Saurabh Sengar <saurabh.truth@xxxxxxxxx>
---
implementing the TODO task

drivers/nfc/nfcsim.c | 38 +++++++++++++++++++++++++++++++++++---
1 file changed, 35 insertions(+), 3 deletions(-)

diff --git a/drivers/nfc/nfcsim.c b/drivers/nfc/nfcsim.c
index 26ac9e5..e77be35 100644
--- a/drivers/nfc/nfcsim.c
+++ b/drivers/nfc/nfcsim.c
@@ -32,6 +32,8 @@
#define NFCSIM_POLL_TARGET 2
#define NFCSIM_POLL_DUAL (NFCSIM_POLL_INITIATOR | NFCSIM_POLL_TARGET)

+#define TX_DEFAULT_DELAY 5
+
struct nfcsim {
struct nfc_dev *nfc_dev;

@@ -62,12 +64,41 @@ static struct nfcsim *dev1;

static struct workqueue_struct *wq;

+
+static int tx_delay = TX_DEFAULT_DELAY;
+
+static ssize_t show_tx_delay(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ int n;
+
+ n = scnprintf(buf, PAGE_SIZE, "%d\n", tx_delay);
+ return n;
+}
+
+static ssize_t store_tx_delay(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ if (kstrtouint(buf, 0, &tx_delay) < 0)
+ return -EINVAL;
+
+ if (tx_delay < 0)
+ return -EINVAL;
+
+ return count;
+}
+
+static DEVICE_ATTR(tx_delay, 0644, show_tx_delay, store_tx_delay);
+
static void nfcsim_cleanup_dev(struct nfcsim *dev, u8 shutdown)
{
DEV_DBG(dev, "shutdown=%d\n", shutdown);

mutex_lock(&dev->lock);

+ device_remove_file(&dev->nfc_dev->dev, &dev_attr_tx_delay);
dev->polling_mode = NFCSIM_POLL_NONE;
dev->shutting_down = shutdown;
dev->cb = NULL;
@@ -320,10 +351,8 @@ static int nfcsim_tx(struct nfc_dev *nfc_dev, struct nfc_target *target,
* If packet transmission occurs immediately between them, we have a
* non-stop flow of several tens of thousands SYMM packets per second
* and a burning cpu.
- *
- * TODO: Add support for a sysfs entry to control this delay.
*/
- queue_delayed_work(wq, &peer->recv_work, msecs_to_jiffies(5));
+ queue_delayed_work(wq, &peer->recv_work, msecs_to_jiffies(tx_delay));

mutex_unlock(&peer->lock);

@@ -461,6 +490,9 @@ static struct nfcsim *nfcsim_init_dev(void)
if (rc)
goto free_nfc_dev;

+ rc = device_create_file(&dev->nfc_dev->dev, &dev_attr_tx_delay);
+ if (rc)
+ pr_err("error creating sysfs entry\n");
return dev;

free_nfc_dev:
--
1.9.1
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/