[PATCH 5/7] smc911x: improve detection handle
Jean-Christophe PLAGNIOL-VILLARD
plagnioj at jcrosoft.com
Sat Sep 1 04:52:42 EDT 2012
detect if the bus is swapped and report a 32bit drivers is used on a 16bit bus
Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj at jcrosoft.com>
---
drivers/net/smc911x.c | 21 ++++++++++++++++++++-
drivers/net/smc911x.h | 2 ++
2 files changed, 22 insertions(+), 1 deletion(-)
diff --git a/drivers/net/smc911x.c b/drivers/net/smc911x.c
index 75a332e..8528527 100644
--- a/drivers/net/smc911x.c
+++ b/drivers/net/smc911x.c
@@ -470,9 +470,28 @@ static int smc911x_probe(struct device_d *dev)
}
val = smc911x_reg_read(priv, BYTE_TEST);
- if(val != 0x87654321) {
+ if (val == 0x43218765) {
+ dev_dbg(dev, "BYTE_TEST looks swapped, "
+ "applying WORD_SWAP");
+ smc911x_reg_write(priv, WORD_SWAP, 0xffffffff);
+
+ /* 1 dummy read of BYTE_TEST is needed after a write to
+ * WORD_SWAP before its contents are valid */
+ val = smc911x_reg_read(priv, BYTE_TEST);
+
+ val = smc911x_reg_read(priv, BYTE_TEST);
+ }
+
+ if (val != 0x87654321) {
dev_err(dev, "no smc911x found on 0x%p (byte_test=0x%08x)\n",
priv->base, val);
+ if (((val >> 16) & 0xFFFF) == (val & 0xFFFF)) {
+ /*
+ * This may mean the chip is set
+ * for 32 bit while the bus is reading 16 bit
+ */
+ dev_err(dev, "top 16 bits equal to bottom 16 bits\n");
+ }
return -ENODEV;
}
diff --git a/drivers/net/smc911x.h b/drivers/net/smc911x.h
index baf3598..d409247 100644
--- a/drivers/net/smc911x.h
+++ b/drivers/net/smc911x.h
@@ -26,6 +26,8 @@
* of the Lan911x memory space
*/
+#define WORD_SWAP 0x98
+
#define RX_DATA_FIFO 0x00
#define TX_DATA_FIFO 0x20
--
1.7.10.4
More information about the barebox
mailing list