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path: root/drivers/net/dm9000.c
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Diffstat (limited to 'drivers/net/dm9000.c')
-rw-r--r--drivers/net/dm9000.c53
1 files changed, 39 insertions, 14 deletions
diff --git a/drivers/net/dm9000.c b/drivers/net/dm9000.c
index fa7eb39dbf3c..a769c89a3690 100644
--- a/drivers/net/dm9000.c
+++ b/drivers/net/dm9000.c
@@ -102,6 +102,24 @@ static int watchdog = 5000;
module_param(watchdog, int, 0400);
MODULE_PARM_DESC(watchdog, "transmit timeout in milliseconds");
+/* DM9000 register address locking.
+ *
+ * The DM9000 uses an address register to control where data written
+ * to the data register goes. This means that the address register
+ * must be preserved over interrupts or similar calls.
+ *
+ * During interrupt and other critical calls, a spinlock is used to
+ * protect the system, but the calls themselves save the address
+ * in the address register in case they are interrupting another
+ * access to the device.
+ *
+ * For general accesses a lock is provided so that calls which are
+ * allowed to sleep are serialised so that the address register does
+ * not need to be saved. This lock also serves to serialise access
+ * to the EEPROM and PHY access registers which are shared between
+ * these two devices.
+ */
+
/* Structure/enum declaration ------------------------------- */
typedef struct board_info {
@@ -132,6 +150,8 @@ typedef struct board_info {
struct resource *data_req;
struct resource *irq_res;
+ struct mutex addr_lock; /* phy and eeprom access lock */
+
spinlock_t lock;
struct mii_if_info mii;
@@ -365,26 +385,16 @@ static void dm9000_get_drvinfo(struct net_device *dev,
static int dm9000_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
{
board_info_t *dm = to_dm9000_board(dev);
- unsigned long flags;
- spin_lock_irqsave(&dm->lock, flags);
mii_ethtool_gset(&dm->mii, cmd);
- spin_lock_irqsave(&dm->lock, flags);
-
return 0;
}
static int dm9000_set_settings(struct net_device *dev, struct ethtool_cmd *cmd)
{
board_info_t *dm = to_dm9000_board(dev);
- unsigned long flags;
- int rc;
-
- spin_lock_irqsave(&dm->lock, flags);
- rc = mii_ethtool_sset(&dm->mii, cmd);
- spin_lock_irqsave(&dm->lock, flags);
- return rc;
+ return mii_ethtool_sset(&dm->mii, cmd);
}
static int dm9000_nway_reset(struct net_device *dev)
@@ -475,6 +485,7 @@ dm9000_probe(struct platform_device *pdev)
db->dev = &pdev->dev;
spin_lock_init(&db->lock);
+ mutex_init(&db->addr_lock);
if (pdev->num_resources < 2) {
ret = -ENODEV;
@@ -997,8 +1008,10 @@ dm9000_rx(struct net_device *dev)
* Read a word data from EEPROM
*/
static void
-dm9000_read_eeprom(board_info_t * db, int offset, unsigned char *to)
+dm9000_read_eeprom(board_info_t *db, int offset, unsigned char *to)
{
+ mutex_lock(&db->addr_lock);
+
iow(db, DM9000_EPAR, offset);
iow(db, DM9000_EPCR, EPCR_ERPRR);
mdelay(8); /* according to the datasheet 200us should be enough,
@@ -1007,6 +1020,8 @@ dm9000_read_eeprom(board_info_t * db, int offset, unsigned char *to)
to[0] = ior(db, DM9000_EPDRL);
to[1] = ior(db, DM9000_EPDRH);
+
+ mutex_unlock(&db->addr_lock);
}
#ifdef DM9000_PROGRAM_EEPROM
@@ -1016,12 +1031,16 @@ dm9000_read_eeprom(board_info_t * db, int offset, unsigned char *to)
static void
write_srom_word(board_info_t * db, int offset, u16 val)
{
+ mutex_lock(&db->addr_lock);
+
iow(db, DM9000_EPAR, offset);
iow(db, DM9000_EPDRH, ((val >> 8) & 0xff));
iow(db, DM9000_EPDRL, (val & 0xff));
iow(db, DM9000_EPCR, EPCR_WEP | EPCR_ERPRW);
mdelay(8); /* same shit */
iow(db, DM9000_EPCR, 0);
+
+ mutex_unlock(&db->addr_lock);
}
/*
@@ -1129,6 +1148,8 @@ dm9000_phy_read(struct net_device *dev, int phy_reg_unused, int reg)
unsigned int reg_save;
int ret;
+ mutex_lock(&db->addr_lock);
+
spin_lock_irqsave(&db->lock,flags);
/* Save previous register address */
@@ -1156,6 +1177,7 @@ dm9000_phy_read(struct net_device *dev, int phy_reg_unused, int reg)
writeb(reg_save, db->io_addr);
spin_unlock_irqrestore(&db->lock,flags);
+ mutex_unlock(&db->addr_lock);
return ret;
}
@@ -1169,6 +1191,8 @@ dm9000_phy_write(struct net_device *dev, int phyaddr_unused, int reg, int value)
unsigned long flags;
unsigned long reg_save;
+ mutex_lock(&db->addr_lock);
+
spin_lock_irqsave(&db->lock,flags);
/* Save previous register address */
@@ -1184,7 +1208,7 @@ dm9000_phy_write(struct net_device *dev, int phyaddr_unused, int reg, int value)
iow(db, DM9000_EPCR, 0xa); /* Issue phyxcer write command */
writeb(reg_save, db->io_addr);
- spin_unlock_irqrestore(&db->lock,flags);
+ spin_unlock_irqrestore(&db->lock, flags);
dm9000_msleep(db, 1); /* Wait write complete */
@@ -1196,7 +1220,8 @@ dm9000_phy_write(struct net_device *dev, int phyaddr_unused, int reg, int value)
/* restore the previous address */
writeb(reg_save, db->io_addr);
- spin_unlock_irqrestore(&db->lock,flags);
+ spin_unlock_irqrestore(&db->lock, flags);
+ mutex_unlock(&db->addr_lock);
}
static int