From: David Brownell <[EMAIL PROTECTED]>
Prevent unaligned packet oops on enc28j60 packet RX.
Keep enc28j60 chips in low-power mode when they're not in use.
At typically 120 mA, these chips run hot even when idle. Low
power mode cuts that power usage by a factor of around 100.
Signed-off-by: David Brownell <[EMAIL PROTECTED]>
---
drivers/net/enc28j60.c | 54 +++++++++++++++++++++++++++++++++++++++++++++----
1 files changed, 50 insertions(+), 4 deletions(-)
--- avr.orig/drivers/net/enc28j60.c 2008-02-05 10:04:22.000000000 -0800
+++ avr/drivers/net/enc28j60.c 2008-02-05 10:50:50.000000000 -0800
@@ -594,6 +594,43 @@ static void nolock_txfifo_init(struct en
nolock_regw_write(priv, ETXNDL, end);
}
+/*
+ * Low power mode shrinks power consumption about 100x, so we'd like
+ * the chip to be in that mode whenever it's inactive.
+ */
+static void enc28j60_lowpower(struct enc28j60_net *priv, bool is_low)
+{
+ int tmp;
+
+ dev_dbg(&priv->spi->dev, "%s power...\n", is_low ? "low" : "high");
+
+ mutex_lock(&priv->lock);
+ if (is_low) {
+ nolock_reg_bfclr(priv, ECON1, ECON1_RXEN);
+ for (;;) {
+ tmp = nolock_regb_read(priv, ESTAT);
+ if (!(tmp & ESTAT_RXBUSY))
+ break;
+ }
+ for (;;) {
+ tmp = nolock_regb_read(priv, ECON1);
+ if (!(tmp & ECON1_TXRTS))
+ break;
+ }
+ /* ECON2_VRPS was set during initialization */
+ nolock_reg_bfset(priv, ECON2, ECON2_PWRSV);
+ } else {
+ nolock_reg_bfclr(priv, ECON2, ECON2_PWRSV);
+ for (;;) {
+ tmp = nolock_regb_read(priv, ESTAT);
+ if (tmp & ESTAT_CLKRDY)
+ break;
+ }
+ /* caller sets ECON1_RXEN */
+ }
+ mutex_unlock(&priv->lock);
+}
+
static int enc28j60_hw_init(struct enc28j60_net *priv)
{
u8 reg;
@@ -612,8 +649,8 @@ static int enc28j60_hw_init(struct enc28
priv->tx_retry_count = 0;
priv->max_pk_counter = 0;
priv->rxfilter = RXFILTER_NORMAL;
- /* enable address auto increment */
- nolock_regb_write(priv, ECON2, ECON2_AUTOINC);
+ /* enable address auto increment and voltage regulator powersave */
+ nolock_regb_write(priv, ECON2, ECON2_AUTOINC | ECON2_VRPS);
nolock_rxfifo_init(priv, RXSTART_INIT, RXEND_INIT);
nolock_txfifo_init(priv, TXSTART_INIT, TXEND_INIT);
@@ -690,7 +727,9 @@ static int enc28j60_hw_init(struct enc28
static void enc28j60_hw_enable(struct enc28j60_net *priv)
{
- /* enable interrutps */
+ enc28j60_lowpower(priv, false);
+
+ /* enable interrupts */
if (netif_msg_hw(priv))
printk(KERN_DEBUG DRV_NAME ": %s() enabling interrupts.\n",
__FUNCTION__);
@@ -717,6 +756,8 @@ static void enc28j60_hw_disable(struct e
nolock_reg_bfclr(priv, ECON1, ECON1_RXEN);
priv->hw_enable = false;
mutex_unlock(&priv->lock);
+
+ enc28j60_lowpower(priv, true);
}
static int
@@ -734,6 +775,8 @@ enc28j60_setlink(struct net_device *ndev
"hw_reset() failed\n");
ret = -EINVAL;
}
+ enc28j60_lowpower(priv, true);
+
} else {
if (netif_msg_link(priv))
dev_warn(&ndev->dev,
@@ -900,7 +943,7 @@ static void enc28j60_hw_rx(struct net_de
if (RSV_GETBIT(rxstat, RSV_LENCHECKERR))
ndev->stats.rx_frame_errors++;
} else {
- skb = dev_alloc_skb(len);
+ skb = dev_alloc_skb(len + NET_IP_ALIGN);
if (!skb) {
if (netif_msg_rx_err(priv))
dev_err(&ndev->dev,
@@ -908,6 +951,7 @@ static void enc28j60_hw_rx(struct net_de
ndev->stats.rx_dropped++;
} else {
skb->dev = ndev;
+ skb_reserve(skb, NET_IP_ALIGN);
/* copy the packet from the receive buffer */
enc28j60_mem_read(priv, priv->next_pk_ptr + sizeof(rsv),
len, skb_put(skb, len));
@@ -1536,6 +1580,8 @@ static int __devinit enc28j60_probe(stru
dev->watchdog_timeo = TX_TIMEOUT;
SET_ETHTOOL_OPS(dev, &enc28j60_ethtool_ops);
+ enc28j60_lowpower(priv, true);
+
ret = register_netdev(dev);
if (ret) {
if (netif_msg_probe(priv))
--
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