net: allow shifted access in smsc911x V2

This is a revised patch that permits a shifted access to the
LAN9221 registers.  More specifically:

 It adds a shift parameter in the platform_data.
 It introduces an ops in smsc911x_data.
 A choice of access function to use at run-time.
 Four new shifted access function.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Alessandro Rubini <rubini@gnudd.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/smsc911x.c b/drivers/net/smsc911x.c
index b8faab7..c6d47d1 100644 (file)
--- a/drivers/net/smsc911x.c
+++ b/drivers/net/smsc911x.c
@@ -71,6 +71,17 @@ static int debug = 3;
 module_param(debug, int, 0);
 MODULE_PARM_DESC(debug, "Debug level (0=none,...,16=all)");
 
+struct smsc911x_data;
+
+struct smsc911x_ops {
+       u32 (*reg_read)(struct smsc911x_data *pdata, u32 reg);
+       void (*reg_write)(struct smsc911x_data *pdata, u32 reg, u32 val);
+       void (*rx_readfifo)(struct smsc911x_data *pdata,
+                               unsigned int *buf, unsigned int wordcount);
+       void (*tx_writefifo)(struct smsc911x_data *pdata,
+                               unsigned int *buf, unsigned int wordcount);
+};
+
 struct smsc911x_data {
        void __iomem *ioaddr;
 
@@ -118,8 +129,14 @@ struct smsc911x_data {
        unsigned int clear_bits_mask;
        unsigned int hashhi;
        unsigned int hashlo;
+
+       /* register access functions */
+       const struct smsc911x_ops *ops;
 };
 
+/* Easy access to information */
+#define __smsc_shift(pdata, reg) ((reg) << ((pdata)->config.shift))
+
 static inline u32 __smsc911x_reg_read(struct smsc911x_data *pdata, u32 reg)
 {
        if (pdata->config.flags & SMSC911X_USE_32BIT)
@@ -133,13 +150,29 @@ static inline u32 __smsc911x_reg_read(struct smsc911x_data *pdata, u32 reg)
        return 0;
 }
 
+static inline u32
+__smsc911x_reg_read_shift(struct smsc911x_data *pdata, u32 reg)
+{
+       if (pdata->config.flags & SMSC911X_USE_32BIT)
+               return readl(pdata->ioaddr + __smsc_shift(pdata, reg));
+
+       if (pdata->config.flags & SMSC911X_USE_16BIT)
+               return (readw(pdata->ioaddr +
+                               __smsc_shift(pdata, reg)) & 0xFFFF) |
+                       ((readw(pdata->ioaddr +
+                       __smsc_shift(pdata, reg + 2)) & 0xFFFF) << 16);
+
+       BUG();
+       return 0;
+}
+
 static inline u32 smsc911x_reg_read(struct smsc911x_data *pdata, u32 reg)
 {
        u32 data;
        unsigned long flags;
 
        spin_lock_irqsave(&pdata->dev_lock, flags);
-       data = __smsc911x_reg_read(pdata, reg);
+       data = pdata->ops->reg_read(pdata, reg);
        spin_unlock_irqrestore(&pdata->dev_lock, flags);
 
        return data;
@@ -162,13 +195,32 @@ static inline void __smsc911x_reg_write(struct smsc911x_data *pdata, u32 reg,
        BUG();
 }
 
+static inline void
+__smsc911x_reg_write_shift(struct smsc911x_data *pdata, u32 reg, u32 val)
+{
+       if (pdata->config.flags & SMSC911X_USE_32BIT) {
+               writel(val, pdata->ioaddr + __smsc_shift(pdata, reg));
+               return;
+       }
+
+       if (pdata->config.flags & SMSC911X_USE_16BIT) {
+               writew(val & 0xFFFF,
+                       pdata->ioaddr + __smsc_shift(pdata, reg));
+               writew((val >> 16) & 0xFFFF,
+                       pdata->ioaddr + __smsc_shift(pdata, reg + 2));
+               return;
+       }
+
+       BUG();
+}
+
 static inline void smsc911x_reg_write(struct smsc911x_data *pdata, u32 reg,
                                      u32 val)
 {
        unsigned long flags;
 
        spin_lock_irqsave(&pdata->dev_lock, flags);
-       __smsc911x_reg_write(pdata, reg, val);
+       pdata->ops->reg_write(pdata, reg, val);
        spin_unlock_irqrestore(&pdata->dev_lock, flags);
 }
 
@@ -204,6 +256,40 @@ out:
        spin_unlock_irqrestore(&pdata->dev_lock, flags);
 }
 
+/* Writes a packet to the TX_DATA_FIFO - shifted version */
+static inline void
+smsc911x_tx_writefifo_shift(struct smsc911x_data *pdata, unsigned int *buf,
+                     unsigned int wordcount)
+{
+       unsigned long flags;
+
+       spin_lock_irqsave(&pdata->dev_lock, flags);
+
+       if (pdata->config.flags & SMSC911X_SWAP_FIFO) {
+               while (wordcount--)
+                       __smsc911x_reg_write_shift(pdata, TX_DATA_FIFO,
+                                            swab32(*buf++));
+               goto out;
+       }
+
+       if (pdata->config.flags & SMSC911X_USE_32BIT) {
+               writesl(pdata->ioaddr + __smsc_shift(pdata,
+                                               TX_DATA_FIFO), buf, wordcount);
+               goto out;
+       }
+
+       if (pdata->config.flags & SMSC911X_USE_16BIT) {
+               while (wordcount--)
+                       __smsc911x_reg_write_shift(pdata,
+                                                TX_DATA_FIFO, *buf++);
+               goto out;
+       }
+
+       BUG();
+out:
+       spin_unlock_irqrestore(&pdata->dev_lock, flags);
+}
+
 /* Reads a packet out of the RX_DATA_FIFO */
 static inline void
 smsc911x_rx_readfifo(struct smsc911x_data *pdata, unsigned int *buf,
@@ -236,6 +322,40 @@ out:
        spin_unlock_irqrestore(&pdata->dev_lock, flags);
 }
 
+/* Reads a packet out of the RX_DATA_FIFO - shifted version */
+static inline void
+smsc911x_rx_readfifo_shift(struct smsc911x_data *pdata, unsigned int *buf,
+                    unsigned int wordcount)
+{
+       unsigned long flags;
+
+       spin_lock_irqsave(&pdata->dev_lock, flags);
+
+       if (pdata->config.flags & SMSC911X_SWAP_FIFO) {
+               while (wordcount--)
+                       *buf++ = swab32(__smsc911x_reg_read_shift(pdata,
+                                                           RX_DATA_FIFO));
+               goto out;
+       }
+
+       if (pdata->config.flags & SMSC911X_USE_32BIT) {
+               readsl(pdata->ioaddr + __smsc_shift(pdata,
+                                               RX_DATA_FIFO), buf, wordcount);
+               goto out;
+       }
+
+       if (pdata->config.flags & SMSC911X_USE_16BIT) {
+               while (wordcount--)
+                       *buf++ = __smsc911x_reg_read_shift(pdata,
+                                                               RX_DATA_FIFO);
+               goto out;
+       }
+
+       BUG();
+out:
+       spin_unlock_irqrestore(&pdata->dev_lock, flags);
+}
+
 /* waits for MAC not busy, with timeout.  Only called by smsc911x_mac_read
  * and smsc911x_mac_write, so assumes mac_lock is held */
 static int smsc911x_mac_complete(struct smsc911x_data *pdata)
@@ -500,7 +620,7 @@ static int smsc911x_phy_check_loopbackpkt(struct smsc911x_data *pdata)
                wrsz += (u32)((ulong)pdata->loopback_tx_pkt & 0x3);
                wrsz >>= 2;
 
-               smsc911x_tx_writefifo(pdata, (unsigned int *)bufp, wrsz);
+               pdata->ops->tx_writefifo(pdata, (unsigned int *)bufp, wrsz);
 
                /* Wait till transmit is done */
                i = 60;
@@ -544,7 +664,7 @@ static int smsc911x_phy_check_loopbackpkt(struct smsc911x_data *pdata)
                rdsz += (u32)((ulong)pdata->loopback_rx_pkt & 0x3);
                rdsz >>= 2;
 
-               smsc911x_rx_readfifo(pdata, (unsigned int *)bufp, rdsz);
+               pdata->ops->rx_readfifo(pdata, (unsigned int *)bufp, rdsz);
 
                if (pktlength != (MIN_PACKET_SIZE + 4)) {
                        SMSC_WARN(pdata, hw, "Unexpected packet size "
@@ -1046,8 +1166,8 @@ static int smsc911x_poll(struct napi_struct *napi, int budget)
                /* Align IP on 16B boundary */
                skb_reserve(skb, NET_IP_ALIGN);
                skb_put(skb, pktlength - 4);
-               smsc911x_rx_readfifo(pdata, (unsigned int *)skb->head,
-                                    pktwords);
+               pdata->ops->rx_readfifo(pdata,
+                                (unsigned int *)skb->head, pktwords);
                skb->protocol = eth_type_trans(skb, dev);
                skb_checksum_none_assert(skb);
                netif_receive_skb(skb);
@@ -1351,7 +1471,7 @@ static int smsc911x_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
        wrsz += (u32)((ulong)skb->data & 0x3);
        wrsz >>= 2;
 
-       smsc911x_tx_writefifo(pdata, (unsigned int *)bufp, wrsz);
+       pdata->ops->tx_writefifo(pdata, (unsigned int *)bufp, wrsz);
        freespace -= (skb->len + 32);
        dev_kfree_skb(skb);
 
@@ -1957,6 +2077,22 @@ static int __devexit smsc911x_drv_remove(struct platform_device *pdev)
        return 0;
 }
 
+/* standard register acces */
+static const struct smsc911x_ops standard_smsc911x_ops = {
+       .reg_read = __smsc911x_reg_read,
+       .reg_write = __smsc911x_reg_write,
+       .rx_readfifo = smsc911x_rx_readfifo,
+       .tx_writefifo = smsc911x_tx_writefifo,
+};
+
+/* shifted register access */
+static const struct smsc911x_ops shifted_smsc911x_ops = {
+       .reg_read = __smsc911x_reg_read_shift,
+       .reg_write = __smsc911x_reg_write_shift,
+       .rx_readfifo = smsc911x_rx_readfifo_shift,
+       .tx_writefifo = smsc911x_tx_writefifo_shift,
+};
+
 static int __devinit smsc911x_drv_probe(struct platform_device *pdev)
 {
        struct net_device *dev;
@@ -2026,6 +2162,12 @@ static int __devinit smsc911x_drv_probe(struct platform_device *pdev)
                goto out_free_netdev_2;
        }
 
+       /* assume standard, non-shifted, access to HW registers */
+       pdata->ops = &standard_smsc911x_ops;
+       /* apply the right access if shifting is needed */
+       if (config->shift)
+               pdata->ops = &shifted_smsc911x_ops;
+
        retval = smsc911x_init(dev);
        if (retval < 0)
                goto out_unmap_io_3;

diff --git a/include/linux/smsc911x.h b/include/linux/smsc911x.h
index 7144e8a..4dde70e 100644 (file)
--- a/include/linux/smsc911x.h
+++ b/include/linux/smsc911x.h
@@ -29,6 +29,7 @@ struct smsc911x_platform_config {
        unsigned int irq_polarity;
        unsigned int irq_type;
        unsigned int flags;
+       unsigned int shift;
        phy_interface_t phy_interface;
        unsigned char mac[6];
 };