cxgb4: Add support for ethtool i2c dump

Adds support for ethtool get_module_info() and get_module_eeprom()
callbacks that will dump necessary information for a SFP.

Signed-off-by: Arjun Vynipadath <arjun@chelsio.com>
Signed-off-by: Casey Leedom <leedom@chelsio.com>
Signed-off-by: Ganesh Goudar <ganeshgr@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 56 insertions, 0 deletions

diff --git a/drivers/net/ethernet/chelsio/cxgb4/t4_hw.c b/drivers/net/ethernet/chelsio/cxgb4/t4_hw.c
index 112963defd0b..f044717aaa10 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/t4_hw.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/t4_hw.c
@@ -9743,3 +9743,59 @@ int t4_sched_params(struct adapter *adapter, int type, int level, int mode,
 	return t4_wr_mbox_meat(adapter, adapter->mbox, &cmd, sizeof(cmd),
 			       NULL, 1);
 }
+
+/**
+ *	t4_i2c_rd - read I2C data from adapter
+ *	@adap: the adapter
+ *	@port: Port number if per-port device; <0 if not
+ *	@devid: per-port device ID or absolute device ID
+ *	@offset: byte offset into device I2C space
+ *	@len: byte length of I2C space data
+ *	@buf: buffer in which to return I2C data
+ *
+ *	Reads the I2C data from the indicated device and location.
+ */
+int t4_i2c_rd(struct adapter *adap, unsigned int mbox, int port,
+	      unsigned int devid, unsigned int offset,
+	      unsigned int len, u8 *buf)
+{
+	struct fw_ldst_cmd ldst_cmd, ldst_rpl;
+	unsigned int i2c_max = sizeof(ldst_cmd.u.i2c.data);
+	int ret = 0;
+
+	if (len > I2C_PAGE_SIZE)
+		return -EINVAL;
+
+	/* Dont allow reads that spans multiple pages */
+	if (offset < I2C_PAGE_SIZE && offset + len > I2C_PAGE_SIZE)
+		return -EINVAL;
+
+	memset(&ldst_cmd, 0, sizeof(ldst_cmd));
+	ldst_cmd.op_to_addrspace =
+		cpu_to_be32(FW_CMD_OP_V(FW_LDST_CMD) |
+			    FW_CMD_REQUEST_F |
+			    FW_CMD_READ_F |
+			    FW_LDST_CMD_ADDRSPACE_V(FW_LDST_ADDRSPC_I2C));
+	ldst_cmd.cycles_to_len16 = cpu_to_be32(FW_LEN16(ldst_cmd));
+	ldst_cmd.u.i2c.pid = (port < 0 ? 0xff : port);
+	ldst_cmd.u.i2c.did = devid;
+
+	while (len > 0) {
+		unsigned int i2c_len = (len < i2c_max) ? len : i2c_max;
+
+		ldst_cmd.u.i2c.boffset = offset;
+		ldst_cmd.u.i2c.blen = i2c_len;
+
+		ret = t4_wr_mbox(adap, mbox, &ldst_cmd, sizeof(ldst_cmd),
+				 &ldst_rpl);
+		if (ret)
+			break;
+
+		memcpy(buf, ldst_rpl.u.i2c.data, i2c_len);
+		offset += i2c_len;
+		buf += i2c_len;
+		len -= i2c_len;
+	}
+
+	return ret;
+}