@@ -690,14 +690,69 @@ static int sfp_i2c_write(struct sfp *sfp, bool a2, u8 dev_addr, void *buf,
return ret == ARRAY_SIZE(msgs) ? len : 0;
}
-static int sfp_i2c_configure(struct sfp *sfp, struct i2c_adapter *i2c)
+static int sfp_smbus_read(struct sfp *sfp, bool a2, u8 dev_addr, void *buf,
+ size_t len)
{
- if (!i2c_check_functionality(i2c, I2C_FUNC_I2C))
- return -EINVAL;
+ u8 bus_addr = a2 ? 0x51 : 0x50;
+ union i2c_smbus_data smbus_data;
+ u8 *data = buf;
+ int ret;
+
+ while (len) {
+ ret = i2c_smbus_xfer(sfp->i2c, bus_addr, 0,
+ I2C_SMBUS_READ, dev_addr,
+ I2C_SMBUS_BYTE_DATA, &smbus_data);
+ if (ret < 0)
+ return ret;
+ *data = smbus_data.byte;
+
+ len--;
+ data++;
+ dev_addr++;
+ }
+
+ return data - (u8 *)buf;
+}
+
+static int sfp_smbus_write(struct sfp *sfp, bool a2, u8 dev_addr, void *buf,
+ size_t len)
+{
+ u8 bus_addr = a2 ? 0x51 : 0x50;
+ union i2c_smbus_data smbus_data;
+ u8 *data = buf;
+ int ret;
+
+ while (len) {
+ smbus_data.byte = *data;
+ ret = i2c_smbus_xfer(sfp->i2c, bus_addr, 0,
+ I2C_SMBUS_WRITE, dev_addr,
+ I2C_SMBUS_BYTE_DATA, &smbus_data);
+ if (ret)
+ return ret;
+
+ len--;
+ data++;
+ dev_addr++;
+ }
+
+ return 0;
+}
+
+static int sfp_i2c_configure(struct sfp *sfp, struct i2c_adapter *i2c)
+{
sfp->i2c = i2c;
- sfp->read = sfp_i2c_read;
- sfp->write = sfp_i2c_write;
+
+ if (i2c_check_functionality(i2c, I2C_FUNC_I2C)) {
+ sfp->read = sfp_i2c_read;
+ sfp->write = sfp_i2c_write;
+ } else if (i2c_check_functionality(i2c, I2C_FUNC_SMBUS_BYTE_DATA)) {
+ sfp->read = sfp_smbus_read;
+ sfp->write = sfp_smbus_write;
+ } else {
+ sfp->i2c = NULL;
+ return -EINVAL;
+ }
return 0;
}
The SFP module's eeprom and internals are accessible through an i2c bus. However, all the i2c transfers that are performed are SMBus-style transfers for read and write operations. It is possible that the SFP might be connected to an SMBus-only controller, such as the one found in some PHY devices in the VSC85xx family. Introduce a set of sfp read/write ops that are going to be used if the i2c bus is only capable of doing smbus byte accesses. Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com> --- drivers/net/phy/sfp.c | 65 +++++++++++++++++++++++++++++++++++++++---- 1 file changed, 60 insertions(+), 5 deletions(-)