[PATCH 1/4] net: w5100: move mmiowb into register access callbacks

[PATCH 1/4] net: w5100: move mmiowb into register access callbacks

[Akinobu Mita]

Instead of sprinkle mmiowb over the driver code, move it into primary
register write callbacks. (w5100_write, w5100_write16, w5100_writebuf)

This is a preparation for supporting SPI interface which doesn't use
MMIO for accessing w5100 registers.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Mike Sinkovsky <msink@permonline.ru>
Cc: David S. Miller <davem@davemloft.net>
---
 drivers/net/ethernet/wiznet/w5100.c | 44 +++++++++++++------------------------
 1 file changed, 15 insertions(+), 29 deletions(-)

diff --git a/drivers/net/ethernet/wiznet/w5100.c b/drivers/net/ethernet/wiznet/w5100.c
index 8b282d0..f4b7200 100644
--- a/drivers/net/ethernet/wiznet/w5100.c
+++ b/drivers/net/ethernet/wiznet/w5100.c
@@ -122,10 +122,17 @@ static inline u8 w5100_read_direct(struct w5100_priv *priv, u16 addr)
 	return ioread8(priv->base + (addr << CONFIG_WIZNET_BUS_SHIFT));
 }
 
+static inline void __w5100_write_direct(struct w5100_priv *priv, u16 addr,
+					u8 data)
+{
+	iowrite8(data, priv->base + (addr << CONFIG_WIZNET_BUS_SHIFT));
+}
+
 static inline void w5100_write_direct(struct w5100_priv *priv,
 				      u16 addr, u8 data)
 {
-	iowrite8(data, priv->base + (addr << CONFIG_WIZNET_BUS_SHIFT));
+	__w5100_write_direct(priv, addr, data);
+	mmiowb();
 }
 
 static u16 w5100_read16_direct(struct w5100_priv *priv, u16 addr)
@@ -138,8 +145,9 @@ static u16 w5100_read16_direct(struct w5100_priv *priv, u16 addr)
 
 static void w5100_write16_direct(struct w5100_priv *priv, u16 addr, u16 data)
 {
-	w5100_write_direct(priv, addr, data >> 8);
-	w5100_write_direct(priv, addr + 1, data);
+	__w5100_write_direct(priv, addr, data >> 8);
+	__w5100_write_direct(priv, addr + 1, data);
+	mmiowb();
 }
 
 static void w5100_readbuf_direct(struct w5100_priv *priv,
@@ -164,8 +172,9 @@ static void w5100_writebuf_direct(struct w5100_priv *priv,
 	for (i = 0; i < len; i++, addr++) {
 		if (unlikely(addr > W5100_TX_MEM_END))
 			addr = W5100_TX_MEM_START;
-		w5100_write_direct(priv, addr, *buf++);
+		__w5100_write_direct(priv, addr, *buf++);
 	}
+	mmiowb();
 }
 
 /*
@@ -186,7 +195,6 @@ static u8 w5100_read_indirect(struct w5100_priv *priv, u16 addr)
 
 	spin_lock_irqsave(&priv->reg_lock, flags);
 	w5100_write16_direct(priv, W5100_IDM_AR, addr);
-	mmiowb();
 	data = w5100_read_direct(priv, W5100_IDM_DR);
 	spin_unlock_irqrestore(&priv->reg_lock, flags);
 
@@ -199,9 +207,7 @@ static void w5100_write_indirect(struct w5100_priv *priv, u16 addr, u8 data)
 
 	spin_lock_irqsave(&priv->reg_lock, flags);
 	w5100_write16_direct(priv, W5100_IDM_AR, addr);
-	mmiowb();
 	w5100_write_direct(priv, W5100_IDM_DR, data);
-	mmiowb();
 	spin_unlock_irqrestore(&priv->reg_lock, flags);
 }
 
@@ -212,7 +218,6 @@ static u16 w5100_read16_indirect(struct w5100_priv *priv, u16 addr)
 
 	spin_lock_irqsave(&priv->reg_lock, flags);
 	w5100_write16_direct(priv, W5100_IDM_AR, addr);
-	mmiowb();
 	data  = w5100_read_direct(priv, W5100_IDM_DR) << 8;
 	data |= w5100_read_direct(priv, W5100_IDM_DR);
 	spin_unlock_irqrestore(&priv->reg_lock, flags);
@@ -226,10 +231,8 @@ static void w5100_write16_indirect(struct w5100_priv *priv, u16 addr, u16 data)
 
 	spin_lock_irqsave(&priv->reg_lock, flags);
 	w5100_write16_direct(priv, W5100_IDM_AR, addr);
-	mmiowb();
-	w5100_write_direct(priv, W5100_IDM_DR, data >> 8);
+	__w5100_write_direct(priv, W5100_IDM_DR, data >> 8);
 	w5100_write_direct(priv, W5100_IDM_DR, data);
-	mmiowb();
 	spin_unlock_irqrestore(&priv->reg_lock, flags);
 }
 
@@ -242,13 +245,11 @@ static void w5100_readbuf_indirect(struct w5100_priv *priv,
 
 	spin_lock_irqsave(&priv->reg_lock, flags);
 	w5100_write16_direct(priv, W5100_IDM_AR, addr);
-	mmiowb();
 
 	for (i = 0; i < len; i++, addr++) {
 		if (unlikely(addr > W5100_RX_MEM_END)) {
 			addr = W5100_RX_MEM_START;
 			w5100_write16_direct(priv, W5100_IDM_AR, addr);
-			mmiowb();
 		}
 		*buf++ = w5100_read_direct(priv, W5100_IDM_DR);
 	}
@@ -265,15 +266,13 @@ static void w5100_writebuf_indirect(struct w5100_priv *priv,
 
 	spin_lock_irqsave(&priv->reg_lock, flags);
 	w5100_write16_direct(priv, W5100_IDM_AR, addr);
-	mmiowb();
 
 	for (i = 0; i < len; i++, addr++) {
 		if (unlikely(addr > W5100_TX_MEM_END)) {
 			addr = W5100_TX_MEM_START;
 			w5100_write16_direct(priv, W5100_IDM_AR, addr);
-			mmiowb();
 		}
-		w5100_write_direct(priv, W5100_IDM_DR, *buf++);
+		__w5100_write_direct(priv, W5100_IDM_DR, *buf++);
 	}
 	mmiowb();
 	spin_unlock_irqrestore(&priv->reg_lock, flags);
@@ -309,7 +308,6 @@ static int w5100_command(struct w5100_priv *priv, u16 cmd)
 	unsigned long timeout = jiffies + msecs_to_jiffies(100);
 
 	w5100_write(priv, W5100_S0_CR, cmd);
-	mmiowb();
 
 	while (w5100_read(priv, W5100_S0_CR) != 0) {
 		if (time_after(jiffies, timeout))
@@ -327,18 +325,15 @@ static void w5100_write_macaddr(struct w5100_priv *priv)
 
 	for (i = 0; i < ETH_ALEN; i++)
 		w5100_write(priv, W5100_SHAR + i, ndev->dev_addr[i]);
-	mmiowb();
 }
 
 static void w5100_hw_reset(struct w5100_priv *priv)
 {
 	w5100_write_direct(priv, W5100_MR, MR_RST);
-	mmiowb();
 	mdelay(5);
 	w5100_write_direct(priv, W5100_MR, priv->indirect ?
 				  MR_PB | MR_AI | MR_IND :
 				  MR_PB);
-	mmiowb();
 	w5100_write(priv, W5100_IMR, 0);
 	w5100_write_macaddr(priv);
 
@@ -347,23 +342,19 @@ static void w5100_hw_reset(struct w5100_priv *priv)
 	 */
 	w5100_write(priv, W5100_RMSR, 0x03);
 	w5100_write(priv, W5100_TMSR, 0x03);
-	mmiowb();
 }
 
 static void w5100_hw_start(struct w5100_priv *priv)
 {
 	w5100_write(priv, W5100_S0_MR, priv->promisc ?
 			  S0_MR_MACRAW : S0_MR_MACRAW_MF);
-	mmiowb();
 	w5100_command(priv, S0_CR_OPEN);
 	w5100_write(priv, W5100_IMR, IR_S0);
-	mmiowb();
 }
 
 static void w5100_hw_close(struct w5100_priv *priv)
 {
 	w5100_write(priv, W5100_IMR, 0);
-	mmiowb();
 	w5100_command(priv, S0_CR_CLOSE);
 }
 
@@ -447,7 +438,6 @@ static int w5100_start_tx(struct sk_buff *skb, struct net_device *ndev)
 	offset = w5100_read16(priv, W5100_S0_TX_WR);
 	w5100_writebuf(priv, offset, skb->data, skb->len);
 	w5100_write16(priv, W5100_S0_TX_WR, offset + skb->len);
-	mmiowb();
 	ndev->stats.tx_bytes += skb->len;
 	ndev->stats.tx_packets++;
 	dev_kfree_skb(skb);
@@ -488,7 +478,6 @@ static int w5100_napi_poll(struct napi_struct *napi, int budget)
 		skb_put(skb, rx_len);
 		w5100_readbuf(priv, offset + 2, skb->data, rx_len);
 		w5100_write16(priv, W5100_S0_RX_RD, offset + 2 + rx_len);
-		mmiowb();
 		w5100_command(priv, S0_CR_RECV);
 		skb->protocol = eth_type_trans(skb, ndev);
 
@@ -500,7 +489,6 @@ static int w5100_napi_poll(struct napi_struct *napi, int budget)
 	if (rx_count < budget) {
 		napi_complete(napi);
 		w5100_write(priv, W5100_IMR, IR_S0);
-		mmiowb();
 	}
 
 	return rx_count;
@@ -515,7 +503,6 @@ static irqreturn_t w5100_interrupt(int irq, void *ndev_instance)
 	if (!ir)
 		return IRQ_NONE;
 	w5100_write(priv, W5100_S0_IR, ir);
-	mmiowb();
 
 	if (ir & S0_IR_SENDOK) {
 		netif_dbg(priv, tx_done, ndev, "tx done\n");
@@ -525,7 +512,6 @@ static irqreturn_t w5100_interrupt(int irq, void *ndev_instance)
 	if (ir & S0_IR_RECV) {
 		if (napi_schedule_prep(&priv->napi)) {
 			w5100_write(priv, W5100_IMR, 0);
-			mmiowb();
 			__napi_schedule(&priv->napi);
 		}
 	}
-- 
2.5.0

[PATCH 2/4] net: w5100: add ability to support other bus interface

[Akinobu Mita]

The w5100 driver currently only supports direct and indirect bus
interface mode which use MMIO space for accessing w5100 registers.

In order to support SPI interface mode which is supported by W5100 chip,
this makes the bus interface abstraction layer more generic so that
separated w5100-spi driver can use w5100 driver as core module.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Mike Sinkovsky <msink@permonline.ru>
Cc: David S. Miller <davem@davemloft.net>
---
 drivers/net/ethernet/wiznet/w5100.c | 588 ++++++++++++++++++++++++------------
 drivers/net/ethernet/wiznet/w5100.h |  26 ++
 2 files changed, 415 insertions(+), 199 deletions(-)
 create mode 100644 drivers/net/ethernet/wiznet/w5100.h

diff --git a/drivers/net/ethernet/wiznet/w5100.c b/drivers/net/ethernet/wiznet/w5100.c
index f4b7200..7290096 100644
--- a/drivers/net/ethernet/wiznet/w5100.c
+++ b/drivers/net/ethernet/wiznet/w5100.c
@@ -27,6 +27,8 @@
 #include <linux/irq.h>
 #include <linux/gpio.h>
 
+#include "w5100.h"
+
 #define DRV_NAME	"w5100"
 #define DRV_VERSION	"2012-04-04"
 
@@ -76,25 +78,21 @@ MODULE_LICENSE("GPL");
 #define W5100_S0_REGS_LEN	0x0040
 
 #define W5100_TX_MEM_START	0x4000
-#define W5100_TX_MEM_END	0x5fff
-#define W5100_TX_MEM_MASK	0x1fff
+#define W5100_TX_MEM_SIZE	0x2000
 #define W5100_RX_MEM_START	0x6000
-#define W5100_RX_MEM_END	0x7fff
-#define W5100_RX_MEM_MASK	0x1fff
+#define W5100_RX_MEM_SIZE	0x2000
 
 /*
  * Device driver private data structure
  */
-struct w5100_priv {
+
+struct w5100_mmio_priv {
 	void __iomem *base;
 	spinlock_t reg_lock;
-	bool indirect;
-	u8   (*read)(struct w5100_priv *priv, u16 addr);
-	void (*write)(struct w5100_priv *priv, u16 addr, u8 data);
-	u16  (*read16)(struct w5100_priv *priv, u16 addr);
-	void (*write16)(struct w5100_priv *priv, u16 addr, u16 data);
-	void (*readbuf)(struct w5100_priv *priv, u16 addr, u8 *buf, int len);
-	void (*writebuf)(struct w5100_priv *priv, u16 addr, u8 *buf, int len);
+};
+
+struct w5100_priv {
+	const struct w5100_ops *ops;
 	int irq;
 	int link_irq;
 	int link_gpio;
@@ -103,6 +101,8 @@ struct w5100_priv {
 	struct net_device *ndev;
 	bool promisc;
 	u32 msg_enable;
+
+	struct w5100_mmio_priv mmio_priv;
 };
 
 /************************************************************************
@@ -111,72 +111,117 @@ struct w5100_priv {
  *
  ***********************************************************************/
 
+static inline struct w5100_mmio_priv *to_w5100_mmio_priv(struct net_device *dev)
+{
+	struct w5100_priv *priv = netdev_priv(dev);
+
+	return &priv->mmio_priv;
+}
+
+static inline void __iomem *w5100_mmio(struct net_device *ndev)
+{
+	struct w5100_mmio_priv *mmio_priv = to_w5100_mmio_priv(ndev);
+
+	return mmio_priv->base;
+}
+
 /*
  * In direct address mode host system can directly access W5100 registers
  * after mapping to Memory-Mapped I/O space.
  *
  * 0x8000 bytes are required for memory space.
  */
-static inline u8 w5100_read_direct(struct w5100_priv *priv, u16 addr)
+static inline int w5100_read_direct(struct net_device *ndev, u16 addr)
 {
-	return ioread8(priv->base + (addr << CONFIG_WIZNET_BUS_SHIFT));
+	return ioread8(w5100_mmio(ndev) + (addr << CONFIG_WIZNET_BUS_SHIFT));
 }
 
-static inline void __w5100_write_direct(struct w5100_priv *priv, u16 addr,
-					u8 data)
+static inline int __w5100_write_direct(struct net_device *ndev, u16 addr,
+				       u8 data)
 {
-	iowrite8(data, priv->base + (addr << CONFIG_WIZNET_BUS_SHIFT));
+	iowrite8(data, w5100_mmio(ndev) + (addr << CONFIG_WIZNET_BUS_SHIFT));
+
+	return 0;
 }
 
-static inline void w5100_write_direct(struct w5100_priv *priv,
-				      u16 addr, u8 data)
+static inline int w5100_write_direct(struct net_device *ndev, u16 addr, u8 data)
 {
-	__w5100_write_direct(priv, addr, data);
+	__w5100_write_direct(ndev, addr, data);
 	mmiowb();
+
+	return 0;
 }
 
-static u16 w5100_read16_direct(struct w5100_priv *priv, u16 addr)
+static int w5100_read16_direct(struct net_device *ndev, u16 addr)
 {
 	u16 data;
-	data  = w5100_read_direct(priv, addr) << 8;
-	data |= w5100_read_direct(priv, addr + 1);
+	data  = w5100_read_direct(ndev, addr) << 8;
+	data |= w5100_read_direct(ndev, addr + 1);
 	return data;
 }
 
-static void w5100_write16_direct(struct w5100_priv *priv, u16 addr, u16 data)
+static int w5100_write16_direct(struct net_device *ndev, u16 addr, u16 data)
 {
-	__w5100_write_direct(priv, addr, data >> 8);
-	__w5100_write_direct(priv, addr + 1, data);
+	__w5100_write_direct(ndev, addr, data >> 8);
+	__w5100_write_direct(ndev, addr + 1, data);
 	mmiowb();
+
+	return 0;
 }
 
-static void w5100_readbuf_direct(struct w5100_priv *priv,
-				 u16 offset, u8 *buf, int len)
+static int w5100_readbulk_direct(struct net_device *ndev, u16 addr, u8 *buf,
+				 int len)
 {
-	u16 addr = W5100_RX_MEM_START + (offset & W5100_RX_MEM_MASK);
 	int i;
 
-	for (i = 0; i < len; i++, addr++) {
-		if (unlikely(addr > W5100_RX_MEM_END))
-			addr = W5100_RX_MEM_START;
-		*buf++ = w5100_read_direct(priv, addr);
-	}
+	for (i = 0; i < len; i++, addr++)
+		*buf++ = w5100_read_direct(ndev, addr);
+
+	return 0;
 }
 
-static void w5100_writebuf_direct(struct w5100_priv *priv,
-				  u16 offset, u8 *buf, int len)
+static int w5100_writebulk_direct(struct net_device *ndev, u16 addr,
+				  const u8 *buf, int len)
 {
-	u16 addr = W5100_TX_MEM_START + (offset & W5100_TX_MEM_MASK);
 	int i;
 
-	for (i = 0; i < len; i++, addr++) {
-		if (unlikely(addr > W5100_TX_MEM_END))
-			addr = W5100_TX_MEM_START;
-		__w5100_write_direct(priv, addr, *buf++);
-	}
+	for (i = 0; i < len; i++, addr++)
+		__w5100_write_direct(ndev, addr, *buf++);
+
 	mmiowb();
+
+	return 0;
 }
 
+static int w5100_mmio_init(struct net_device *ndev)
+{
+	struct platform_device *pdev = to_platform_device(ndev->dev.parent);
+	struct w5100_priv *priv = netdev_priv(ndev);
+	struct w5100_mmio_priv *mmio_priv = to_w5100_mmio_priv(ndev);
+	struct resource *mem;
+
+	spin_lock_init(&mmio_priv->reg_lock);
+
+	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	mmio_priv->base = devm_ioremap_resource(&pdev->dev, mem);
+	if (IS_ERR(mmio_priv->base))
+		return PTR_ERR(mmio_priv->base);
+
+	netdev_info(ndev, "at 0x%llx irq %d\n", (u64)mem->start, priv->irq);
+
+	return 0;
+}
+
+static const struct w5100_ops w5100_mmio_direct_ops = {
+	.read = w5100_read_direct,
+	.write = w5100_write_direct,
+	.read16 = w5100_read16_direct,
+	.write16 = w5100_write16_direct,
+	.readbulk = w5100_readbulk_direct,
+	.writebulk = w5100_writebulk_direct,
+	.init = w5100_mmio_init,
+};
+
 /*
  * In indirect address mode host system indirectly accesses registers by
  * using Indirect Mode Address Register (IDM_AR) and Indirect Mode Data
@@ -188,121 +233,276 @@ static void w5100_writebuf_direct(struct w5100_priv *priv,
 #define W5100_IDM_AR		0x01   /* Indirect Mode Address Register */
 #define W5100_IDM_DR		0x03   /* Indirect Mode Data Register */
 
-static u8 w5100_read_indirect(struct w5100_priv *priv, u16 addr)
+static int w5100_read_indirect(struct net_device *ndev, u16 addr)
 {
+	struct w5100_mmio_priv *mmio_priv = to_w5100_mmio_priv(ndev);
 	unsigned long flags;
 	u8 data;
 
-	spin_lock_irqsave(&priv->reg_lock, flags);
-	w5100_write16_direct(priv, W5100_IDM_AR, addr);
-	data = w5100_read_direct(priv, W5100_IDM_DR);
-	spin_unlock_irqrestore(&priv->reg_lock, flags);
+	spin_lock_irqsave(&mmio_priv->reg_lock, flags);
+	w5100_write16_direct(ndev, W5100_IDM_AR, addr);
+	data = w5100_read_direct(ndev, W5100_IDM_DR);
+	spin_unlock_irqrestore(&mmio_priv->reg_lock, flags);
 
 	return data;
 }
 
-static void w5100_write_indirect(struct w5100_priv *priv, u16 addr, u8 data)
+static int w5100_write_indirect(struct net_device *ndev, u16 addr, u8 data)
 {
+	struct w5100_mmio_priv *mmio_priv = to_w5100_mmio_priv(ndev);
 	unsigned long flags;
 
-	spin_lock_irqsave(&priv->reg_lock, flags);
-	w5100_write16_direct(priv, W5100_IDM_AR, addr);
-	w5100_write_direct(priv, W5100_IDM_DR, data);
-	spin_unlock_irqrestore(&priv->reg_lock, flags);
+	spin_lock_irqsave(&mmio_priv->reg_lock, flags);
+	w5100_write16_direct(ndev, W5100_IDM_AR, addr);
+	w5100_write_direct(ndev, W5100_IDM_DR, data);
+	spin_unlock_irqrestore(&mmio_priv->reg_lock, flags);
+
+	return 0;
 }
 
-static u16 w5100_read16_indirect(struct w5100_priv *priv, u16 addr)
+static int w5100_read16_indirect(struct net_device *ndev, u16 addr)
 {
+	struct w5100_mmio_priv *mmio_priv = to_w5100_mmio_priv(ndev);
 	unsigned long flags;
 	u16 data;
 
-	spin_lock_irqsave(&priv->reg_lock, flags);
-	w5100_write16_direct(priv, W5100_IDM_AR, addr);
-	data  = w5100_read_direct(priv, W5100_IDM_DR) << 8;
-	data |= w5100_read_direct(priv, W5100_IDM_DR);
-	spin_unlock_irqrestore(&priv->reg_lock, flags);
+	spin_lock_irqsave(&mmio_priv->reg_lock, flags);
+	w5100_write16_direct(ndev, W5100_IDM_AR, addr);
+	data  = w5100_read_direct(ndev, W5100_IDM_DR) << 8;
+	data |= w5100_read_direct(ndev, W5100_IDM_DR);
+	spin_unlock_irqrestore(&mmio_priv->reg_lock, flags);
 
 	return data;
 }
 
-static void w5100_write16_indirect(struct w5100_priv *priv, u16 addr, u16 data)
+static int w5100_write16_indirect(struct net_device *ndev, u16 addr, u16 data)
 {
+	struct w5100_mmio_priv *mmio_priv = to_w5100_mmio_priv(ndev);
 	unsigned long flags;
 
-	spin_lock_irqsave(&priv->reg_lock, flags);
-	w5100_write16_direct(priv, W5100_IDM_AR, addr);
-	__w5100_write_direct(priv, W5100_IDM_DR, data >> 8);
-	w5100_write_direct(priv, W5100_IDM_DR, data);
-	spin_unlock_irqrestore(&priv->reg_lock, flags);
+	spin_lock_irqsave(&mmio_priv->reg_lock, flags);
+	w5100_write16_direct(ndev, W5100_IDM_AR, addr);
+	__w5100_write_direct(ndev, W5100_IDM_DR, data >> 8);
+	w5100_write_direct(ndev, W5100_IDM_DR, data);
+	spin_unlock_irqrestore(&mmio_priv->reg_lock, flags);
+
+	return 0;
 }
 
-static void w5100_readbuf_indirect(struct w5100_priv *priv,
-				   u16 offset, u8 *buf, int len)
+static int w5100_readbulk_indirect(struct net_device *ndev, u16 addr, u8 *buf,
+				   int len)
 {
-	u16 addr = W5100_RX_MEM_START + (offset & W5100_RX_MEM_MASK);
+	struct w5100_mmio_priv *mmio_priv = to_w5100_mmio_priv(ndev);
 	unsigned long flags;
 	int i;
 
-	spin_lock_irqsave(&priv->reg_lock, flags);
-	w5100_write16_direct(priv, W5100_IDM_AR, addr);
+	spin_lock_irqsave(&mmio_priv->reg_lock, flags);
+	w5100_write16_direct(ndev, W5100_IDM_AR, addr);
+
+	for (i = 0; i < len; i++)
+		*buf++ = w5100_read_direct(ndev, W5100_IDM_DR);
 
-	for (i = 0; i < len; i++, addr++) {
-		if (unlikely(addr > W5100_RX_MEM_END)) {
-			addr = W5100_RX_MEM_START;
-			w5100_write16_direct(priv, W5100_IDM_AR, addr);
-		}
-		*buf++ = w5100_read_direct(priv, W5100_IDM_DR);
-	}
 	mmiowb();
-	spin_unlock_irqrestore(&priv->reg_lock, flags);
+	spin_unlock_irqrestore(&mmio_priv->reg_lock, flags);
+
+	return 0;
 }
 
-static void w5100_writebuf_indirect(struct w5100_priv *priv,
-				    u16 offset, u8 *buf, int len)
+static int w5100_writebulk_indirect(struct net_device *ndev, u16 addr,
+				    const u8 *buf, int len)
 {
-	u16 addr = W5100_TX_MEM_START + (offset & W5100_TX_MEM_MASK);
+	struct w5100_mmio_priv *mmio_priv = to_w5100_mmio_priv(ndev);
 	unsigned long flags;
 	int i;
 
-	spin_lock_irqsave(&priv->reg_lock, flags);
-	w5100_write16_direct(priv, W5100_IDM_AR, addr);
+	spin_lock_irqsave(&mmio_priv->reg_lock, flags);
+	w5100_write16_direct(ndev, W5100_IDM_AR, addr);
+
+	for (i = 0; i < len; i++)
+		__w5100_write_direct(ndev, W5100_IDM_DR, *buf++);
 
-	for (i = 0; i < len; i++, addr++) {
-		if (unlikely(addr > W5100_TX_MEM_END)) {
-			addr = W5100_TX_MEM_START;
-			w5100_write16_direct(priv, W5100_IDM_AR, addr);
-		}
-		__w5100_write_direct(priv, W5100_IDM_DR, *buf++);
-	}
 	mmiowb();
-	spin_unlock_irqrestore(&priv->reg_lock, flags);
+	spin_unlock_irqrestore(&mmio_priv->reg_lock, flags);
+
+	return 0;
 }
 
+static int w5100_reset_indirect(struct net_device *ndev)
+{
+	w5100_write_direct(ndev, W5100_MR, MR_RST);
+	mdelay(5);
+	w5100_write_direct(ndev, W5100_MR, MR_PB | MR_AI | MR_IND);
+
+	return 0;
+}
+
+static const struct w5100_ops w5100_mmio_indirect_ops = {
+	.read = w5100_read_indirect,
+	.write = w5100_write_indirect,
+	.read16 = w5100_read16_indirect,
+	.write16 = w5100_write16_indirect,
+	.readbulk = w5100_readbulk_indirect,
+	.writebulk = w5100_writebulk_indirect,
+	.init = w5100_mmio_init,
+	.reset = w5100_reset_indirect,
+};
+
 #if defined(CONFIG_WIZNET_BUS_DIRECT)
-#define w5100_read	w5100_read_direct
-#define w5100_write	w5100_write_direct
-#define w5100_read16	w5100_read16_direct
-#define w5100_write16	w5100_write16_direct
-#define w5100_readbuf	w5100_readbuf_direct
-#define w5100_writebuf	w5100_writebuf_direct
+
+static int w5100_read(struct w5100_priv *priv, u16 addr)
+{
+	return w5100_read_direct(priv->ndev, addr);
+}
+
+static int w5100_write(struct w5100_priv *priv, u16 addr, u8 data)
+{
+	return w5100_write_direct(priv->ndev, addr, data);
+}
+
+static int w5100_read16(struct w5100_priv *priv, u16 addr)
+{
+	return w5100_read16_direct(priv->ndev, addr);
+}
+
+static int w5100_write16(struct w5100_priv *priv, u16 addr, u16 data)
+{
+	return w5100_write16_direct(priv->ndev, addr, data);
+}
+
+static int w5100_readbulk(struct w5100_priv *priv, u16 addr, u8 *buf, int len)
+{
+	return w5100_readbulk_direct(priv->ndev, addr, buf, len);
+}
+
+static int w5100_writebulk(struct w5100_priv *priv, u16 addr, const u8 *buf,
+			   int len)
+{
+	return w5100_writebulk_direct(priv->ndev, addr, buf, len);
+}
 
 #elif defined(CONFIG_WIZNET_BUS_INDIRECT)
-#define w5100_read	w5100_read_indirect
-#define w5100_write	w5100_write_indirect
-#define w5100_read16	w5100_read16_indirect
-#define w5100_write16	w5100_write16_indirect
-#define w5100_readbuf	w5100_readbuf_indirect
-#define w5100_writebuf	w5100_writebuf_indirect
+
+static int w5100_read(struct w5100_priv *priv, u16 addr)
+{
+	return w5100_read_indirect(priv->ndev, addr);
+}
+
+static int w5100_write(struct w5100_priv *priv, u16 addr, u8 data)
+{
+	return w5100_write_indirect(priv->ndev, addr, data);
+}
+
+static int w5100_read16(struct w5100_priv *priv, u16 addr)
+{
+	return w5100_read16_indirect(priv->ndev, addr);
+}
+
+static int w5100_write16(struct w5100_priv *priv, u16 addr, u16 data)
+{
+	return w5100_write16_indirect(priv->ndev, addr, data);
+}
+
+static int w5100_readbulk(struct w5100_priv *priv, u16 addr, u8 *buf, int len)
+{
+	return w5100_readbulk_indirect(priv->ndev, addr, buf, len);
+}
+
+static int w5100_writebulk(struct w5100_priv *priv, u16 addr, const u8 *buf,
+			   int len)
+{
+	return w5100_writebulk_indirect(priv->ndev, addr, buf, len);
+}
 
 #else /* CONFIG_WIZNET_BUS_ANY */
-#define w5100_read	priv->read
-#define w5100_write	priv->write
-#define w5100_read16	priv->read16
-#define w5100_write16	priv->write16
-#define w5100_readbuf	priv->readbuf
-#define w5100_writebuf	priv->writebuf
+
+static int w5100_read(struct w5100_priv *priv, u16 addr)
+{
+	return priv->ops->read(priv->ndev, addr);
+}
+
+static int w5100_write(struct w5100_priv *priv, u16 addr, u8 data)
+{
+	return priv->ops->write(priv->ndev, addr, data);
+}
+
+static int w5100_read16(struct w5100_priv *priv, u16 addr)
+{
+	return priv->ops->read16(priv->ndev, addr);
+}
+
+static int w5100_write16(struct w5100_priv *priv, u16 addr, u16 data)
+{
+	return priv->ops->write16(priv->ndev, addr, data);
+}
+
+static int w5100_readbulk(struct w5100_priv *priv, u16 addr, u8 *buf, int len)
+{
+	return priv->ops->readbulk(priv->ndev, addr, buf, len);
+}
+
+static int w5100_writebulk(struct w5100_priv *priv, u16 addr, const u8 *buf,
+			   int len)
+{
+	return priv->ops->writebulk(priv->ndev, addr, buf, len);
+}
+
 #endif
 
+static int w5100_readbuf(struct w5100_priv *priv, u16 offset, u8 *buf, int len)
+{
+	u16 addr;
+	int remain = 0;
+	int ret;
+
+	offset %= W5100_RX_MEM_SIZE;
+	addr = W5100_RX_MEM_START + offset;
+
+	if (offset + len > W5100_RX_MEM_SIZE) {
+		remain = (offset + len) % W5100_RX_MEM_SIZE;
+		len = W5100_RX_MEM_SIZE - offset;
+	}
+
+	ret = w5100_readbulk(priv, addr, buf, len);
+	if (ret || !remain)
+		return ret;
+
+	return w5100_readbulk(priv, W5100_RX_MEM_START, buf + len, remain);
+}
+
+static int w5100_writebuf(struct w5100_priv *priv, u16 offset, const u8 *buf,
+			  int len)
+{
+	u16 addr;
+	int ret;
+	int remain = 0;
+
+	offset %= W5100_TX_MEM_SIZE;
+	addr = W5100_TX_MEM_START + offset;
+
+	if (offset + len > W5100_TX_MEM_SIZE) {
+		remain = (offset + len) % W5100_TX_MEM_SIZE;
+		len = W5100_TX_MEM_SIZE - offset;
+	}
+
+	ret = w5100_writebulk(priv, addr, buf, len);
+	if (ret || !remain)
+		return ret;
+
+	return w5100_writebulk(priv, W5100_TX_MEM_START, buf + len, remain);
+}
+
+static int w5100_reset(struct w5100_priv *priv)
+{
+	if (priv->ops->reset)
+		return priv->ops->reset(priv->ndev);
+
+	w5100_write(priv, W5100_MR, MR_RST);
+	mdelay(5);
+	w5100_write(priv, W5100_MR, MR_PB);
+
+	return 0;
+}
+
 static int w5100_command(struct w5100_priv *priv, u16 cmd)
 {
 	unsigned long timeout = jiffies + msecs_to_jiffies(100);
@@ -321,19 +521,14 @@ static int w5100_command(struct w5100_priv *priv, u16 cmd)
 static void w5100_write_macaddr(struct w5100_priv *priv)
 {
 	struct net_device *ndev = priv->ndev;
-	int i;
 
-	for (i = 0; i < ETH_ALEN; i++)
-		w5100_write(priv, W5100_SHAR + i, ndev->dev_addr[i]);
+	w5100_writebulk(priv, W5100_SHAR, ndev->dev_addr, ETH_ALEN);
 }
 
 static void w5100_hw_reset(struct w5100_priv *priv)
 {
-	w5100_write_direct(priv, W5100_MR, MR_RST);
-	mdelay(5);
-	w5100_write_direct(priv, W5100_MR, priv->indirect ?
-				  MR_PB | MR_AI | MR_IND :
-				  MR_PB);
+	w5100_reset(priv);
+
 	w5100_write(priv, W5100_IMR, 0);
 	w5100_write_macaddr(priv);
 
@@ -403,17 +598,14 @@ static int w5100_get_regs_len(struct net_device *ndev)
 }
 
 static void w5100_get_regs(struct net_device *ndev,
-			   struct ethtool_regs *regs, void *_buf)
+			   struct ethtool_regs *regs, void *buf)
 {
 	struct w5100_priv *priv = netdev_priv(ndev);
-	u8 *buf = _buf;
-	u16 i;
 
 	regs->version = 1;
-	for (i = 0; i < W5100_COMMON_REGS_LEN; i++)
-		*buf++ = w5100_read(priv, W5100_COMMON_REGS + i);
-	for (i = 0; i < W5100_S0_REGS_LEN; i++)
-		*buf++ = w5100_read(priv, W5100_S0_REGS + i);
+	w5100_readbulk(priv, W5100_COMMON_REGS, buf, W5100_COMMON_REGS_LEN);
+	buf += W5100_COMMON_REGS_LEN;
+	w5100_readbulk(priv, W5100_S0_REGS, buf, W5100_S0_REGS_LEN);
 }
 
 static void w5100_tx_timeout(struct net_device *ndev)
@@ -606,79 +798,38 @@ static const struct net_device_ops w5100_netdev_ops = {
 	.ndo_change_mtu		= eth_change_mtu,
 };
 
-static int w5100_hw_probe(struct platform_device *pdev)
+static int w5100_mmio_probe(struct platform_device *pdev)
 {
 	struct wiznet_platform_data *data = dev_get_platdata(&pdev->dev);
-	struct net_device *ndev = platform_get_drvdata(pdev);
-	struct w5100_priv *priv = netdev_priv(ndev);
-	const char *name = netdev_name(ndev);
+	u8 *mac_addr = NULL;
 	struct resource *mem;
-	int mem_size;
+	const struct w5100_ops *ops;
 	int irq;
-	int ret;
 
-	if (data && is_valid_ether_addr(data->mac_addr)) {
-		memcpy(ndev->dev_addr, data->mac_addr, ETH_ALEN);
-	} else {
-		eth_hw_addr_random(ndev);
-	}
+	if (data && is_valid_ether_addr(data->mac_addr))
+		mac_addr = data->mac_addr;
 
 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	priv->base = devm_ioremap_resource(&pdev->dev, mem);
-	if (IS_ERR(priv->base))
-		return PTR_ERR(priv->base);
-
-	mem_size = resource_size(mem);
-
-	spin_lock_init(&priv->reg_lock);
-	priv->indirect = mem_size < W5100_BUS_DIRECT_SIZE;
-	if (priv->indirect) {
-		priv->read     = w5100_read_indirect;
-		priv->write    = w5100_write_indirect;
-		priv->read16   = w5100_read16_indirect;
-		priv->write16  = w5100_write16_indirect;
-		priv->readbuf  = w5100_readbuf_indirect;
-		priv->writebuf = w5100_writebuf_indirect;
-	} else {
-		priv->read     = w5100_read_direct;
-		priv->write    = w5100_write_direct;
-		priv->read16   = w5100_read16_direct;
-		priv->write16  = w5100_write16_direct;
-		priv->readbuf  = w5100_readbuf_direct;
-		priv->writebuf = w5100_writebuf_direct;
-	}
-
-	w5100_hw_reset(priv);
-	if (w5100_read16(priv, W5100_RTR) != RTR_DEFAULT)
-		return -ENODEV;
+	if (resource_size(mem) < W5100_BUS_DIRECT_SIZE)
+		ops = &w5100_mmio_indirect_ops;
+	else
+		ops = &w5100_mmio_direct_ops;
 
 	irq = platform_get_irq(pdev, 0);
 	if (irq < 0)
 		return irq;
-	ret = request_irq(irq, w5100_interrupt,
-			  IRQ_TYPE_LEVEL_LOW, name, ndev);
-	if (ret < 0)
-		return ret;
-	priv->irq = irq;
 
-	priv->link_gpio = data ? data->link_gpio : -EINVAL;
-	if (gpio_is_valid(priv->link_gpio)) {
-		char *link_name = devm_kzalloc(&pdev->dev, 16, GFP_KERNEL);
-		if (!link_name)
-			return -ENOMEM;
-		snprintf(link_name, 16, "%s-link", name);
-		priv->link_irq = gpio_to_irq(priv->link_gpio);
-		if (request_any_context_irq(priv->link_irq, w5100_detect_link,
-				IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
-				link_name, priv->ndev) < 0)
-			priv->link_gpio = -EINVAL;
-	}
+	return w5100_probe(&pdev->dev, ops, mac_addr, irq,
+			   data ? data->link_gpio : -EINVAL);
+}
 
-	netdev_info(ndev, "at 0x%llx irq %d\n", (u64)mem->start, irq);
-	return 0;
+static int w5100_mmio_remove(struct platform_device *pdev)
+{
+	return w5100_remove(&pdev->dev);
 }
 
-static int w5100_probe(struct platform_device *pdev)
+int w5100_probe(struct device *dev, const struct w5100_ops *ops, u8 *mac_addr,
+		int irq, int link_gpio)
 {
 	struct w5100_priv *priv;
 	struct net_device *ndev;
@@ -687,10 +838,13 @@ static int w5100_probe(struct platform_device *pdev)
 	ndev = alloc_etherdev(sizeof(*priv));
 	if (!ndev)
 		return -ENOMEM;
-	SET_NETDEV_DEV(ndev, &pdev->dev);
-	platform_set_drvdata(pdev, ndev);
+	SET_NETDEV_DEV(ndev, dev);
+	dev_set_drvdata(dev, ndev);
 	priv = netdev_priv(ndev);
 	priv->ndev = ndev;
+	priv->ops = ops;
+	priv->irq = irq;
+	priv->link_gpio = link_gpio;
 
 	ndev->netdev_ops = &w5100_netdev_ops;
 	ndev->ethtool_ops = &w5100_ethtool_ops;
@@ -706,22 +860,59 @@ static int w5100_probe(struct platform_device *pdev)
 	if (err < 0)
 		goto err_register;
 
-	err = w5100_hw_probe(pdev);
-	if (err < 0)
-		goto err_hw_probe;
+	if (mac_addr)
+		memcpy(ndev->dev_addr, mac_addr, ETH_ALEN);
+	else
+		eth_hw_addr_random(ndev);
+
+	if (priv->ops->init) {
+		err = priv->ops->init(priv->ndev);
+		if (err)
+			goto err_hw;
+	}
+
+	w5100_hw_reset(priv);
+	if (w5100_read16(priv, W5100_RTR) != RTR_DEFAULT) {
+		err = -ENODEV;
+		goto err_hw;
+	}
+
+	err = request_irq(priv->irq, w5100_interrupt, IRQF_TRIGGER_LOW,
+			  netdev_name(ndev), ndev);
+	if (err)
+		goto err_hw;
+
+	if (gpio_is_valid(priv->link_gpio)) {
+		char *link_name = devm_kzalloc(dev, 16, GFP_KERNEL);
+
+		if (!link_name) {
+			err = -ENOMEM;
+			goto err_gpio;
+		}
+		snprintf(link_name, 16, "%s-link", netdev_name(ndev));
+		priv->link_irq = gpio_to_irq(priv->link_gpio);
+		if (request_any_context_irq(priv->link_irq, w5100_detect_link,
+					    IRQF_TRIGGER_RISING |
+					    IRQF_TRIGGER_FALLING,
+					    link_name, priv->ndev) < 0)
+			priv->link_gpio = -EINVAL;
+	}
 
 	return 0;
 
-err_hw_probe:
+err_gpio:
+	free_irq(priv->irq, ndev);
+err_hw:
 	unregister_netdev(ndev);
 err_register:
 	free_netdev(ndev);
 	return err;
 }
+EXPORT_SYMBOL_GPL(w5100_probe);
 
-static int w5100_remove(struct platform_device *pdev)
+int w5100_remove(struct device *dev)
 {
-	struct net_device *ndev = platform_get_drvdata(pdev);
+	struct net_device *ndev = dev_get_drvdata(dev);
 	struct w5100_priv *priv = netdev_priv(ndev);
 
 	w5100_hw_reset(priv);
@@ -733,12 +924,12 @@ static int w5100_remove(struct platform_device *pdev)
 	free_netdev(ndev);
 	return 0;
 }
+EXPORT_SYMBOL_GPL(w5100_remove);
 
 #ifdef CONFIG_PM_SLEEP
 static int w5100_suspend(struct device *dev)
 {
-	struct platform_device *pdev = to_platform_device(dev);
-	struct net_device *ndev = platform_get_drvdata(pdev);
+	struct net_device *ndev = dev_get_drvdata(dev);
 	struct w5100_priv *priv = netdev_priv(ndev);
 
 	if (netif_running(ndev)) {
@@ -752,8 +943,7 @@ static int w5100_suspend(struct device *dev)
 
 static int w5100_resume(struct device *dev)
 {
-	struct platform_device *pdev = to_platform_device(dev);
-	struct net_device *ndev = platform_get_drvdata(pdev);
+	struct net_device *ndev = dev_get_drvdata(dev);
 	struct w5100_priv *priv = netdev_priv(ndev);
 
 	if (netif_running(ndev)) {
@@ -769,15 +959,15 @@ static int w5100_resume(struct device *dev)
 }
 #endif /* CONFIG_PM_SLEEP */
 
-static SIMPLE_DEV_PM_OPS(w5100_pm_ops, w5100_suspend, w5100_resume);
+SIMPLE_DEV_PM_OPS(w5100_pm_ops, w5100_suspend, w5100_resume);
+EXPORT_SYMBOL_GPL(w5100_pm_ops);
 
-static struct platform_driver w5100_driver = {
+static struct platform_driver w5100_mmio_driver = {
 	.driver		= {
 		.name	= DRV_NAME,
 		.pm	= &w5100_pm_ops,
 	},
-	.probe		= w5100_probe,
-	.remove		= w5100_remove,
+	.probe		= w5100_mmio_probe,
+	.remove		= w5100_mmio_remove,
 };
-
-module_platform_driver(w5100_driver);
+module_platform_driver(w5100_mmio_driver);
diff --git a/drivers/net/ethernet/wiznet/w5100.h b/drivers/net/ethernet/wiznet/w5100.h
new file mode 100644
index 0000000..368862d
--- /dev/null
+++ b/drivers/net/ethernet/wiznet/w5100.h
@@ -0,0 +1,26 @@
+/*
+ * Ethernet driver for the WIZnet W5100 chip.
+ *
+ * Copyright (C) 2006-2008 WIZnet Co.,Ltd.
+ * Copyright (C) 2012 Mike Sinkovsky <msink@permonline.ru>
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+struct w5100_ops {
+	int (*read)(struct net_device *ndev, u16 addr);
+	int (*write)(struct net_device *ndev, u16 addr, u8 data);
+	int (*read16)(struct net_device *ndev, u16 addr);
+	int (*write16)(struct net_device *ndev, u16 addr, u16 data);
+	int (*readbulk)(struct net_device *ndev, u16 addr, u8 *buf, int len);
+	int (*writebulk)(struct net_device *ndev, u16 addr, const u8 *buf,
+			 int len);
+	int (*reset)(struct net_device *ndev);
+	int (*init)(struct net_device *ndev);
+};
+
+int w5100_probe(struct device *dev, const struct w5100_ops *ops, u8 *mac_addr,
+		int irq, int link_gpio);
+int w5100_remove(struct device *dev);
+
+extern const struct dev_pm_ops w5100_pm_ops;
-- 
2.5.0

[PATCH 3/4] net: w5100: enable to support sleepable register access interface

[Akinobu Mita]

SPI transfer routines are callable only from contexts that can sleep.

This adds ability to tell the core driver that the interface mode
cannot access w5100 register on atomic contexts.  In this case,
workqueue and threaded irq are required.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Mike Sinkovsky <msink@permonline.ru>
Cc: David S. Miller <davem@davemloft.net>
---
 drivers/net/ethernet/wiznet/w5100.c | 184 ++++++++++++++++++++++++++++--------
 drivers/net/ethernet/wiznet/w5100.h |   1 +
 2 files changed, 148 insertions(+), 37 deletions(-)

diff --git a/drivers/net/ethernet/wiznet/w5100.c b/drivers/net/ethernet/wiznet/w5100.c
index 7290096..a2a0c59 100644
--- a/drivers/net/ethernet/wiznet/w5100.c
+++ b/drivers/net/ethernet/wiznet/w5100.c
@@ -102,6 +102,13 @@ struct w5100_priv {
 	bool promisc;
 	u32 msg_enable;
 
+	struct workqueue_struct *xfer_wq;
+	struct work_struct rx_work;
+	struct sk_buff_head tx_queue;
+	struct work_struct tx_work;
+	struct work_struct setrx_work;
+	struct work_struct restart_work;
+
 	struct w5100_mmio_priv mmio_priv;
 };
 
@@ -608,7 +615,7 @@ static void w5100_get_regs(struct net_device *ndev,
 	w5100_readbulk(priv, W5100_S0_REGS, buf, W5100_S0_REGS_LEN);
 }
 
-static void w5100_tx_timeout(struct net_device *ndev)
+static void w5100_restart(struct net_device *ndev)
 {
 	struct w5100_priv *priv = netdev_priv(ndev);
 
@@ -620,12 +627,28 @@ static void w5100_tx_timeout(struct net_device *ndev)
 	netif_wake_queue(ndev);
 }
 
-static int w5100_start_tx(struct sk_buff *skb, struct net_device *ndev)
+static void w5100_restart_work(struct work_struct *work)
+{
+	struct w5100_priv *priv = container_of(work, struct w5100_priv,
+					       restart_work);
+
+	w5100_restart(priv->ndev);
+}
+
+static void w5100_tx_timeout(struct net_device *ndev)
 {
 	struct w5100_priv *priv = netdev_priv(ndev);
-	u16 offset;
 
-	netif_stop_queue(ndev);
+	if (priv->ops->may_sleep)
+		schedule_work(&priv->restart_work);
+	else
+		w5100_restart(ndev);
+}
+
+static void w5100_tx_skb(struct net_device *ndev, struct sk_buff *skb)
+{
+	struct w5100_priv *priv = netdev_priv(ndev);
+	u16 offset;
 
 	offset = w5100_read16(priv, W5100_S0_TX_WR);
 	w5100_writebuf(priv, offset, skb->data, skb->len);
@@ -635,47 +658,94 @@ static int w5100_start_tx(struct sk_buff *skb, struct net_device *ndev)
 	dev_kfree_skb(skb);
 
 	w5100_command(priv, S0_CR_SEND);
+}
+
+static void w5100_tx_work(struct work_struct *work)
+{
+	struct w5100_priv *priv = container_of(work, struct w5100_priv,
+					       tx_work);
+	struct sk_buff *skb;
+
+	while ((skb = skb_dequeue(&priv->tx_queue)))
+		w5100_tx_skb(priv->ndev, skb);
+}
+
+static int w5100_start_tx(struct sk_buff *skb, struct net_device *ndev)
+{
+	struct w5100_priv *priv = netdev_priv(ndev);
+
+	netif_stop_queue(ndev);
+
+	if (priv->ops->may_sleep) {
+		skb_queue_tail(&priv->tx_queue, skb);
+		queue_work(priv->xfer_wq, &priv->tx_work);
+	} else {
+		w5100_tx_skb(ndev, skb);
+	}
 
 	return NETDEV_TX_OK;
 }
 
-static int w5100_napi_poll(struct napi_struct *napi, int budget)
+static struct sk_buff *w5100_rx_skb(struct net_device *ndev)
 {
-	struct w5100_priv *priv = container_of(napi, struct w5100_priv, napi);
-	struct net_device *ndev = priv->ndev;
+	struct w5100_priv *priv = netdev_priv(ndev);
 	struct sk_buff *skb;
-	int rx_count;
 	u16 rx_len;
 	u16 offset;
 	u8 header[2];
+	u16 rx_buf_len = w5100_read16(priv, W5100_S0_RX_RSR);
 
-	for (rx_count = 0; rx_count < budget; rx_count++) {
-		u16 rx_buf_len = w5100_read16(priv, W5100_S0_RX_RSR);
-		if (rx_buf_len == 0)
-			break;
+	if (rx_buf_len == 0)
+		return NULL;
 
-		offset = w5100_read16(priv, W5100_S0_RX_RD);
-		w5100_readbuf(priv, offset, header, 2);
-		rx_len = get_unaligned_be16(header) - 2;
-
-		skb = netdev_alloc_skb_ip_align(ndev, rx_len);
-		if (unlikely(!skb)) {
-			w5100_write16(priv, W5100_S0_RX_RD,
-					    offset + rx_buf_len);
-			w5100_command(priv, S0_CR_RECV);
-			ndev->stats.rx_dropped++;
-			return -ENOMEM;
-		}
+	offset = w5100_read16(priv, W5100_S0_RX_RD);
+	w5100_readbuf(priv, offset, header, 2);
+	rx_len = get_unaligned_be16(header) - 2;
 
-		skb_put(skb, rx_len);
-		w5100_readbuf(priv, offset + 2, skb->data, rx_len);
-		w5100_write16(priv, W5100_S0_RX_RD, offset + 2 + rx_len);
+	skb = netdev_alloc_skb_ip_align(ndev, rx_len);
+	if (unlikely(!skb)) {
+		w5100_write16(priv, W5100_S0_RX_RD, offset + rx_buf_len);
 		w5100_command(priv, S0_CR_RECV);
-		skb->protocol = eth_type_trans(skb, ndev);
+		ndev->stats.rx_dropped++;
+		return NULL;
+	}
+
+	skb_put(skb, rx_len);
+	w5100_readbuf(priv, offset + 2, skb->data, rx_len);
+	w5100_write16(priv, W5100_S0_RX_RD, offset + 2 + rx_len);
+	w5100_command(priv, S0_CR_RECV);
+	skb->protocol = eth_type_trans(skb, ndev);
+
+	ndev->stats.rx_packets++;
+	ndev->stats.rx_bytes += rx_len;
+
+	return skb;
+}
+
+static void w5100_rx_work(struct work_struct *work)
+{
+	struct w5100_priv *priv = container_of(work, struct w5100_priv,
+					       rx_work);
+	struct sk_buff *skb;
+
+	while ((skb = w5100_rx_skb(priv->ndev)))
+		netif_rx_ni(skb);
+
+	w5100_write(priv, W5100_IMR, IR_S0);
+}
+
+static int w5100_napi_poll(struct napi_struct *napi, int budget)
+{
+	struct w5100_priv *priv = container_of(napi, struct w5100_priv, napi);
+	int rx_count;
+
+	for (rx_count = 0; rx_count < budget; rx_count++) {
+		struct sk_buff *skb = w5100_rx_skb(priv->ndev);
 
-		netif_receive_skb(skb);
-		ndev->stats.rx_packets++;
-		ndev->stats.rx_bytes += rx_len;
+		if (skb)
+			netif_receive_skb(skb);
+		else
+			break;
 	}
 
 	if (rx_count < budget) {
@@ -702,10 +772,12 @@ static irqreturn_t w5100_interrupt(int irq, void *ndev_instance)
 	}
 
 	if (ir & S0_IR_RECV) {
-		if (napi_schedule_prep(&priv->napi)) {
-			w5100_write(priv, W5100_IMR, 0);
+		w5100_write(priv, W5100_IMR, 0);
+
+		if (priv->ops->may_sleep)
+			queue_work(priv->xfer_wq, &priv->rx_work);
+		else if (napi_schedule_prep(&priv->napi))
 			__napi_schedule(&priv->napi);
-		}
 	}
 
 	return IRQ_HANDLED;
@@ -729,6 +801,14 @@ static irqreturn_t w5100_detect_link(int irq, void *ndev_instance)
 	return IRQ_HANDLED;
 }
 
+static void w5100_setrx_work(struct work_struct *work)
+{
+	struct w5100_priv *priv = container_of(work, struct w5100_priv,
+					       setrx_work);
+
+	w5100_hw_start(priv);
+}
+
 static void w5100_set_rx_mode(struct net_device *ndev)
 {
 	struct w5100_priv *priv = netdev_priv(ndev);
@@ -736,7 +816,11 @@ static void w5100_set_rx_mode(struct net_device *ndev)
 
 	if (priv->promisc != set_promisc) {
 		priv->promisc = set_promisc;
-		w5100_hw_start(priv);
+
+		if (priv->ops->may_sleep)
+			schedule_work(&priv->setrx_work);
+		else
+			w5100_hw_start(priv);
 	}
 }
 
@@ -860,6 +944,18 @@ int w5100_probe(struct device *dev, const struct w5100_ops *ops, u8 *mac_addr,
 	if (err < 0)
 		goto err_register;
 
+	priv->xfer_wq = create_workqueue(netdev_name(ndev));
+	if (!priv->xfer_wq) {
+		err = -ENOMEM;
+		goto err_wq;
+	}
+
+	skb_queue_head_init(&priv->tx_queue);
+	INIT_WORK(&priv->rx_work, w5100_rx_work);
+	INIT_WORK(&priv->tx_work, w5100_tx_work);
+	INIT_WORK(&priv->setrx_work, w5100_setrx_work);
+	INIT_WORK(&priv->restart_work, w5100_restart_work);
+
 	if (mac_addr)
 		memcpy(ndev->dev_addr, mac_addr, ETH_ALEN);
 	else
@@ -877,8 +973,14 @@ int w5100_probe(struct device *dev, const struct w5100_ops *ops, u8 *mac_addr,
 		goto err_hw;
 	}
 
-	err = request_irq(priv->irq, w5100_interrupt, IRQF_TRIGGER_LOW,
-			  netdev_name(ndev), ndev);
+	if (ops->may_sleep) {
+		err = request_threaded_irq(priv->irq, NULL, w5100_interrupt,
+					   IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+					   netdev_name(ndev), ndev);
+	} else {
+		err = request_irq(priv->irq, w5100_interrupt,
+				  IRQF_TRIGGER_LOW, netdev_name(ndev), ndev);
+	}
 	if (err)
 		goto err_hw;
 
@@ -903,6 +1005,8 @@ int w5100_probe(struct device *dev, const struct w5100_ops *ops, u8 *mac_addr,
 err_gpio:
 	free_irq(priv->irq, ndev);
 err_hw:
+	destroy_workqueue(priv->xfer_wq);
+err_wq:
 	unregister_netdev(ndev);
 err_register:
 	free_netdev(ndev);
@@ -920,6 +1024,12 @@ int w5100_remove(struct device *dev)
 	if (gpio_is_valid(priv->link_gpio))
 		free_irq(priv->link_irq, ndev);
 
+	flush_work(&priv->setrx_work);
+	flush_work(&priv->restart_work);
+	flush_workqueue(priv->xfer_wq);
+	skb_queue_purge(&priv->tx_queue);
+	destroy_workqueue(priv->xfer_wq);
+
 	unregister_netdev(ndev);
 	free_netdev(ndev);
 	return 0;
diff --git a/drivers/net/ethernet/wiznet/w5100.h b/drivers/net/ethernet/wiznet/w5100.h
index 368862d..292fbd5 100644
--- a/drivers/net/ethernet/wiznet/w5100.h
+++ b/drivers/net/ethernet/wiznet/w5100.h
@@ -8,6 +8,7 @@
  */
 
 struct w5100_ops {
+	bool may_sleep;
 	int (*read)(struct net_device *ndev, u16 addr);
 	int (*write)(struct net_device *ndev, u16 addr, u8 data);
 	int (*read16)(struct net_device *ndev, u16 addr);
-- 
2.5.0

Re: [PATCH 3/4] net: w5100: enable to support sleepable register access interface

[David Miller]

From: Akinobu Mita <akinobu.mita@gmail.com>
Date: Thu, 31 Mar 2016 01:38:39 +0900

> +	struct sk_buff_head tx_queue;

The way the queueing works in this driver is that it is only possible
to have one SKB being transmitted at one time.

This is evident by how the driver immediately stops the TX queue when
it is given a new packet to transmit, and this is woken up by the TX
completion IRQ.

So don't use a queue here, just use a plain single pointer.

The SKB queue you're using here is going to also do locking which is
even more unnecessary overhead.

Thanks.

Re: [PATCH 3/4] net: w5100: enable to support sleepable register access interface

[Akinobu Mita]

2016-04-01 4:30 GMT+09:00 David Miller <davem@davemloft.net>:
> From: Akinobu Mita <akinobu.mita@gmail.com>
> Date: Thu, 31 Mar 2016 01:38:39 +0900
>
>> +     struct sk_buff_head tx_queue;
>
> The way the queueing works in this driver is that it is only possible
> to have one SKB being transmitted at one time.
>
> This is evident by how the driver immediately stops the TX queue when
> it is given a new packet to transmit, and this is woken up by the TX
> completion IRQ.
>
> So don't use a queue here, just use a plain single pointer.
>
> The SKB queue you're using here is going to also do locking which is
> even more unnecessary overhead.

Thanks for spotting this.  Using a single pointer works fine.

Maybe we can support sending multiple packets at a time, but it should be
another separated patch.

[PATCH 4/4] net: w5100: support SPI interface mode

[Akinobu Mita]

This adds new w5100-spi driver which shares the bus interface
independent code with existing w5100 driver.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Mike Sinkovsky <msink@permonline.ru>
Cc: David S. Miller <davem@davemloft.net>
---
 drivers/net/ethernet/wiznet/Kconfig     |  14 ++++
 drivers/net/ethernet/wiznet/Makefile    |   1 +
 drivers/net/ethernet/wiznet/w5100-spi.c | 135 ++++++++++++++++++++++++++++++++
 3 files changed, 150 insertions(+)
 create mode 100644 drivers/net/ethernet/wiznet/w5100-spi.c

diff --git a/drivers/net/ethernet/wiznet/Kconfig b/drivers/net/ethernet/wiznet/Kconfig
index f98b91d..d1ab353 100644
--- a/drivers/net/ethernet/wiznet/Kconfig
+++ b/drivers/net/ethernet/wiznet/Kconfig
@@ -69,4 +69,18 @@ config WIZNET_BUS_ANY
 	  Performance may decrease compared to explicitly selected bus mode.
 endchoice
 
+config WIZNET_W5100_SPI
+	tristate "WIZnet W5100 Ethernet support for SPI mode"
+	depends on WIZNET_BUS_ANY
+	depends on SPI
+	---help---
+	  In SPI mode host system accesses registers using SPI protocol
+	  (mode 0) on the SPI bus.
+
+	  Performance decreases compared to other bus interface mode.
+	  In W5100 SPI mode, burst READ/WRITE processing are not provided.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called w5100-spi.
+
 endif # NET_VENDOR_WIZNET
diff --git a/drivers/net/ethernet/wiznet/Makefile b/drivers/net/ethernet/wiznet/Makefile
index c614535..1e05e1a 100644
--- a/drivers/net/ethernet/wiznet/Makefile
+++ b/drivers/net/ethernet/wiznet/Makefile
@@ -1,2 +1,3 @@
 obj-$(CONFIG_WIZNET_W5100) += w5100.o
+obj-$(CONFIG_WIZNET_W5100_SPI) += w5100-spi.o
 obj-$(CONFIG_WIZNET_W5300) += w5300.o
diff --git a/drivers/net/ethernet/wiznet/w5100-spi.c b/drivers/net/ethernet/wiznet/w5100-spi.c
new file mode 100644
index 0000000..cf2b845
--- /dev/null
+++ b/drivers/net/ethernet/wiznet/w5100-spi.c
@@ -0,0 +1,135 @@
+/*
+ * Ethernet driver for the WIZnet W5100 chip.
+ *
+ * Copyright (C) 2016 Akinobu Mita <akinobu.mita@gmail.com>
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/netdevice.h>
+#include <linux/spi/spi.h>
+
+#include "w5100.h"
+
+#define W5100_SPI_WRITE_OPCODE 0xf0
+#define W5100_SPI_READ_OPCODE 0x0f
+
+static int w5100_spi_read(struct net_device *ndev, u16 addr)
+{
+	struct spi_device *spi = to_spi_device(ndev->dev.parent);
+	u8 cmd[3] = { W5100_SPI_READ_OPCODE, addr >> 8, addr & 0xff };
+	u8 data;
+	int ret;
+
+	ret = spi_write_then_read(spi, cmd, sizeof(cmd), &data, 1);
+
+	return ret ? ret : data;
+}
+
+static int w5100_spi_write(struct net_device *ndev, u16 addr, u8 data)
+{
+	struct spi_device *spi = to_spi_device(ndev->dev.parent);
+	u8 cmd[4] = { W5100_SPI_WRITE_OPCODE, addr >> 8, addr & 0xff, data};
+
+	return spi_write(spi, cmd, sizeof(cmd));
+}
+
+static int w5100_spi_read16(struct net_device *ndev, u16 addr)
+{
+	u16 data;
+	int ret;
+
+	ret = w5100_spi_read(ndev, addr);
+	if (ret < 0)
+		return ret;
+	data = ret << 8;
+	ret = w5100_spi_read(ndev, addr + 1);
+
+	return ret < 0 ? ret : data | ret;
+}
+
+static int w5100_spi_write16(struct net_device *ndev, u16 addr, u16 data)
+{
+	int ret;
+
+	ret = w5100_spi_write(ndev, addr, data >> 8);
+	if (ret)
+		return ret;
+
+	return w5100_spi_write(ndev, addr + 1, data & 0xff);
+}
+
+static int w5100_spi_readbulk(struct net_device *ndev, u16 addr, u8 *buf,
+			      int len)
+{
+	int i;
+
+	for (i = 0; i < len; i++) {
+		int ret = w5100_spi_read(ndev, addr + i);
+
+		if (ret < 0)
+			return ret;
+		buf[i] = ret;
+	}
+
+	return 0;
+}
+
+static int w5100_spi_writebulk(struct net_device *ndev, u16 addr, const u8 *buf,
+			       int len)
+{
+	int i;
+
+	for (i = 0; i < len; i++) {
+		int ret = w5100_spi_write(ndev, addr + i, buf[i]);
+
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static const struct w5100_ops w5100_spi_ops = {
+	.may_sleep = true,
+	.read = w5100_spi_read,
+	.write = w5100_spi_write,
+	.read16 = w5100_spi_read16,
+	.write16 = w5100_spi_write16,
+	.readbulk = w5100_spi_readbulk,
+	.writebulk = w5100_spi_writebulk,
+};
+
+static int w5100_spi_probe(struct spi_device *spi)
+{
+	return w5100_probe(&spi->dev, &w5100_spi_ops, NULL, spi->irq, -EINVAL);
+}
+
+static int w5100_spi_remove(struct spi_device *spi)
+{
+	return w5100_remove(&spi->dev);
+}
+
+static const struct spi_device_id w5100_spi_ids[] = {
+	{ "w5100", 0 },
+	{}
+};
+MODULE_DEVICE_TABLE(spi, w5100_spi_ids);
+
+static struct spi_driver w5100_spi_driver = {
+	.driver		= {
+		.name	= "w5100",
+		.pm	= &w5100_pm_ops,
+	},
+	.probe		= w5100_spi_probe,
+	.remove		= w5100_spi_remove,
+	.id_table	= w5100_spi_ids,
+};
+module_spi_driver(w5100_spi_driver);
+
+MODULE_DESCRIPTION("WIZnet W5100 Ethernet driver for SPI mode");
+MODULE_AUTHOR("Akinobu Mita <akinobu.mita@gmail.com>");
+MODULE_LICENSE("GPL");
-- 
2.5.0