[PATCH net-next v2 01/13] net: phy: sfp: make the i2c-bus property really optional

Antoine Tenart antoine.tenart at bootlin.com
Fri May 4 06:56:31 PDT 2018


The SFF,SFP documentation is clear about making all the DT properties,
with the exception of the compatible, optional. In practice this is not
the case and without an i2c-bus property provided the SFP code will
throw NULL pointer exceptions.

This patch is an attempt to fix this.

Signed-off-by: Antoine Tenart <antoine.tenart at bootlin.com>
---
 drivers/net/phy/sfp.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/net/phy/sfp.c b/drivers/net/phy/sfp.c
index 4ab6e9a50bbe..4686c443fc22 100644
--- a/drivers/net/phy/sfp.c
+++ b/drivers/net/phy/sfp.c
@@ -298,11 +298,17 @@ static void sfp_set_state(struct sfp *sfp, unsigned int state)
 
 static int sfp_read(struct sfp *sfp, bool a2, u8 addr, void *buf, size_t len)
 {
+	if (!sfp->read)
+		return -EOPNOTSUPP;
+
 	return sfp->read(sfp, a2, addr, buf, len);
 }
 
 static int sfp_write(struct sfp *sfp, bool a2, u8 addr, void *buf, size_t len)
 {
+	if (!sfp->write)
+		return -EOPNOTSUPP;
+
 	return sfp->write(sfp, a2, addr, buf, len);
 }
 
@@ -533,6 +539,8 @@ static int sfp_sm_mod_hpower(struct sfp *sfp)
 		return 0;
 
 	err = sfp_read(sfp, true, SFP_EXT_STATUS, &val, sizeof(val));
+	if (err == -EOPNOTSUPP)
+		goto err;
 	if (err != sizeof(val)) {
 		dev_err(sfp->dev, "Failed to read EEPROM: %d\n", err);
 		err = -EAGAIN;
@@ -542,6 +550,8 @@ static int sfp_sm_mod_hpower(struct sfp *sfp)
 	val |= BIT(0);
 
 	err = sfp_write(sfp, true, SFP_EXT_STATUS, &val, sizeof(val));
+	if (err == -EOPNOTSUPP)
+		goto err;
 	if (err != sizeof(val)) {
 		dev_err(sfp->dev, "Failed to write EEPROM: %d\n", err);
 		err = -EAGAIN;
@@ -565,6 +575,8 @@ static int sfp_sm_mod_probe(struct sfp *sfp)
 	int ret;
 
 	ret = sfp_read(sfp, false, 0, &id, sizeof(id));
+	if (ret == -EOPNOTSUPP)
+		return ret;
 	if (ret < 0) {
 		dev_err(sfp->dev, "failed to read EEPROM: %d\n", ret);
 		return -EAGAIN;
-- 
2.17.0




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