staging: ks7010: use linux circular buffer header macros to handle tx and rx queues

This commit replace current custom implementation of some circular
buffer head and tail logic in favour of the use of macros defined
in linux circ_buf.h header. Queue related inline function names
have been review also.
Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/ks7010/ks7010_sdio.c

@@ -10,6 +10,7 @@
  *   published by the Free Software Foundation.
  */
 
+#include <linux/circ_buf.h>
 #include <linux/firmware.h>
 #include <linux/mmc/card.h>
 #include <linux/mmc/sdio_func.h>
@@ -43,11 +44,10 @@ static inline void inc_txqtail(struct ks_wlan_private *priv)
 	priv->tx_dev.qtail = (priv->tx_dev.qtail + 1) % TX_DEVICE_BUFF_SIZE;
 }
 
-static inline unsigned int cnt_txqbody(struct ks_wlan_private *priv)
+static inline bool txq_has_space(struct ks_wlan_private *priv)
 {
-	unsigned int tx_cnt = priv->tx_dev.qtail - priv->tx_dev.qhead;
-
-	return (tx_cnt + TX_DEVICE_BUFF_SIZE) % TX_DEVICE_BUFF_SIZE;
+	return (CIRC_SPACE(priv->tx_dev.qhead, priv->tx_dev.qtail,
+			   TX_DEVICE_BUFF_SIZE) > 0);
 }
 
 static inline void inc_rxqhead(struct ks_wlan_private *priv)
@@ -60,11 +60,22 @@ static inline void inc_rxqtail(struct ks_wlan_private *priv)
 	priv->rx_dev.qtail = (priv->rx_dev.qtail + 1) % RX_DEVICE_BUFF_SIZE;
 }
 
-static inline unsigned int cnt_rxqbody(struct ks_wlan_private *priv)
+static inline bool rxq_has_space(struct ks_wlan_private *priv)
+{
+	return (CIRC_SPACE(priv->rx_dev.qhead, priv->rx_dev.qtail,
+			   RX_DEVICE_BUFF_SIZE) > 0);
+}
+
+static inline unsigned int txq_count(struct ks_wlan_private *priv)
 {
-	unsigned int rx_cnt = priv->rx_dev.qtail - priv->rx_dev.qhead;
+	return CIRC_CNT_TO_END(priv->tx_dev.qhead, priv->tx_dev.qtail,
+			       TX_DEVICE_BUFF_SIZE);
+}
 
-	return (rx_cnt + RX_DEVICE_BUFF_SIZE) % RX_DEVICE_BUFF_SIZE;
+static inline unsigned int rxq_count(struct ks_wlan_private *priv)
+{
+	return CIRC_CNT_TO_END(priv->rx_dev.qhead, priv->rx_dev.qtail,
+			       RX_DEVICE_BUFF_SIZE);
 }
 
 /* Read single byte from device address into byte (CMD52) */
@@ -190,11 +201,11 @@ static void _ks_wlan_hw_power_save(struct ks_wlan_private *priv)
 		   atomic_read(&priv->psstatus.status),
 		   atomic_read(&priv->psstatus.confirm_wait),
 		   atomic_read(&priv->psstatus.snooze_guard),
-		   cnt_txqbody(priv));
+		   txq_count(priv));
 
 	if (atomic_read(&priv->psstatus.confirm_wait) ||
 	    atomic_read(&priv->psstatus.snooze_guard) ||
-	    cnt_txqbody(priv)) {
+	    txq_has_space(priv)) {
 		queue_delayed_work(priv->wq, &priv->rw_dwork, 0);
 		return;
 	}
@@ -240,7 +251,7 @@ static int enqueue_txdev(struct ks_wlan_private *priv, unsigned char *p,
 		goto err_complete;
 	}
 
-	if ((TX_DEVICE_BUFF_SIZE - 1) <= cnt_txqbody(priv)) {
+	if ((TX_DEVICE_BUFF_SIZE - 1) <= txq_count(priv)) {
 		netdev_err(priv->net_dev, "tx buffer overflow\n");
 		ret = -EOVERFLOW;
 		goto err_complete;
@@ -298,7 +309,7 @@ static void tx_device_task(struct ks_wlan_private *priv)
 	struct tx_device_buffer *sp;
 	int ret;
 
-	if (cnt_txqbody(priv) <= 0 ||
+	if (!txq_has_space(priv) ||
 	    atomic_read(&priv->psstatus.status) == PS_SNOOZE)
 		return;
 
@@ -317,7 +328,7 @@ static void tx_device_task(struct ks_wlan_private *priv)
 		(*sp->complete_handler)(priv, sp->skb);
 	inc_txqhead(priv);
 
-	if (cnt_txqbody(priv) > 0)
+	if (txq_has_space(priv))
 		queue_delayed_work(priv->wq, &priv->rw_dwork, 0);
 }
 
@@ -345,7 +356,7 @@ int ks_wlan_hw_tx(struct ks_wlan_private *priv, void *p, unsigned long size,
 	result = enqueue_txdev(priv, p, size, complete_handler, skb);
 	spin_unlock(&priv->tx_dev.tx_dev_lock);
 
-	if (cnt_txqbody(priv) > 0)
+	if (txq_has_space(priv))
 		queue_delayed_work(priv->wq, &priv->rw_dwork, 0);
 
 	return result;
@@ -356,12 +367,12 @@ static void rx_event_task(unsigned long dev)
 	struct ks_wlan_private *priv = (struct ks_wlan_private *)dev;
 	struct rx_device_buffer *rp;
 
-	if (cnt_rxqbody(priv) > 0 && priv->dev_state >= DEVICE_STATE_BOOT) {
+	if (rxq_has_space(priv) && priv->dev_state >= DEVICE_STATE_BOOT) {
 		rp = &priv->rx_dev.rx_dev_buff[priv->rx_dev.qhead];
 		hostif_receive(priv, rp->data, rp->size);
 		inc_rxqhead(priv);
 
-		if (cnt_rxqbody(priv) > 0)
+		if (rxq_has_space(priv))
 			tasklet_schedule(&priv->rx_bh_task);
 	}
 }
@@ -374,7 +385,7 @@ static void ks_wlan_hw_rx(struct ks_wlan_private *priv, uint16_t size)
 	unsigned short event = 0;
 
 	/* receive data */
-	if (cnt_rxqbody(priv) >= (RX_DEVICE_BUFF_SIZE - 1)) {
+	if (rxq_count(priv) >= (RX_DEVICE_BUFF_SIZE - 1)) {
 		netdev_err(priv->net_dev, "rx buffer overflow\n");
 		return;
 	}
@@ -447,7 +458,7 @@ static void ks7010_rw_function(struct work_struct *work)
 
 	/* power save wakeup */
 	if (atomic_read(&priv->psstatus.status) == PS_SNOOZE) {
-		if (cnt_txqbody(priv) > 0) {
+		if (txq_has_space(priv)) {
 			ks_wlan_hw_wakeup_request(priv);
 			queue_delayed_work(priv->wq, &priv->rw_dwork, 1);
 		}
@@ -538,7 +549,7 @@ static void ks_sdio_interrupt(struct sdio_func *func)
 
 		if (byte & WSTATUS_MASK) {
 			if (atomic_read(&priv->psstatus.status) == PS_SNOOZE) {
-				if (cnt_txqbody(priv)) {
+				if (txq_has_space(priv)) {
 					ks_wlan_hw_wakeup_request(priv);
 					queue_delayed_work(priv->wq,
 							   &priv->rw_dwork, 1);
@@ -575,7 +586,7 @@ static void trx_device_exit(struct ks_wlan_private *priv)
 	struct tx_device_buffer *sp;
 
 	/* tx buffer clear */
-	while (cnt_txqbody(priv) > 0) {
+	while (txq_has_space(priv)) {
 		sp = &priv->tx_dev.tx_dev_buff[priv->tx_dev.qhead];
 		kfree(sp->sendp);
 		if (sp->complete_handler)	/* TX Complete */