ice: add i2c write command

Add the possibility to write to connected i2c devices using the AQ
command. FW may reject the write if the device is not on allowlist.

Signed-off-by: Karol Kolacinski <karol.kolacinski@intel.com>
Tested-by: Gurucharan <gurucharanx.g@intel.com> (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

drivers/net/ethernet/intel/ice/ice_adminq_cmd.h

@@ -1395,7 +1395,7 @@ struct ice_aqc_get_link_topo {
 	u8 rsvd[9];
 };
 
-/* Read I2C (direct, 0x06E2) */
+/* Read/Write I2C (direct, 0x06E2/0x06E3) */
 struct ice_aqc_i2c {
 	struct ice_aqc_link_topo_addr topo_addr;
 	__le16 i2c_addr;
@@ -1405,7 +1405,7 @@ struct ice_aqc_i2c {
 
 	u8 rsvd;
 	__le16 i2c_bus_addr;
-	u8 rsvd2[4];
+	u8 i2c_data[4]; /* Used only by write command, reserved in read. */
 };
 
 /* Read I2C Response (direct, 0x06E2) */
@@ -2124,7 +2124,7 @@ struct ice_aq_desc {
 		struct ice_aqc_get_link_status get_link_status;
 		struct ice_aqc_event_lan_overflow lan_overflow;
 		struct ice_aqc_get_link_topo get_link_topo;
-		struct ice_aqc_i2c read_i2c;
+		struct ice_aqc_i2c read_write_i2c;
 		struct ice_aqc_read_i2c_resp read_i2c_resp;
 	} params;
 };
@@ -2241,6 +2241,7 @@ enum ice_adminq_opc {
 	ice_aqc_opc_set_mac_lb				= 0x0620,
 	ice_aqc_opc_get_link_topo			= 0x06E0,
 	ice_aqc_opc_read_i2c				= 0x06E2,
+	ice_aqc_opc_write_i2c				= 0x06E3,
 	ice_aqc_opc_set_port_id_led			= 0x06E9,
 	ice_aqc_opc_set_gpio				= 0x06EC,
 	ice_aqc_opc_get_gpio				= 0x06ED,

drivers/net/ethernet/intel/ice/ice_common.c

@@ -4823,7 +4823,7 @@ ice_aq_read_i2c(struct ice_hw *hw, struct ice_aqc_link_topo_addr topo_addr,
 	int status;
 
 	ice_fill_dflt_direct_cmd_desc(&desc, ice_aqc_opc_read_i2c);
-	cmd = &desc.params.read_i2c;
+	cmd = &desc.params.read_write_i2c;
 
 	if (!data)
 		return -EINVAL;
@@ -4850,6 +4850,51 @@ ice_aq_read_i2c(struct ice_hw *hw, struct ice_aqc_link_topo_addr topo_addr,
 	return status;
 }
 
+/**
+ * ice_aq_write_i2c
+ * @hw: pointer to the hw struct
+ * @topo_addr: topology address for a device to communicate with
+ * @bus_addr: 7-bit I2C bus address
+ * @addr: I2C memory address (I2C offset) with up to 16 bits
+ * @params: I2C parameters: bit [4] - I2C address type, bits [3:0] - data size to write (0-7 bytes)
+ * @data: pointer to data (0 to 4 bytes) to be written to the I2C device
+ * @cd: pointer to command details structure or NULL
+ *
+ * Write I2C (0x06E3)
+ *
+ * * Return:
+ * * 0             - Successful write to the i2c device
+ * * -EINVAL       - Data size greater than 4 bytes
+ * * -EIO          - FW error
+ */
+int
+ice_aq_write_i2c(struct ice_hw *hw, struct ice_aqc_link_topo_addr topo_addr,
+		 u16 bus_addr, __le16 addr, u8 params, u8 *data,
+		 struct ice_sq_cd *cd)
+{
+	struct ice_aq_desc desc = { 0 };
+	struct ice_aqc_i2c *cmd;
+	u8 data_size;
+
+	ice_fill_dflt_direct_cmd_desc(&desc, ice_aqc_opc_write_i2c);
+	cmd = &desc.params.read_write_i2c;
+
+	data_size = FIELD_GET(ICE_AQC_I2C_DATA_SIZE_M, params);
+
+	/* data_size limited to 4 */
+	if (data_size > 4)
+		return -EINVAL;
+
+	cmd->i2c_bus_addr = cpu_to_le16(bus_addr);
+	cmd->topo_addr = topo_addr;
+	cmd->i2c_params = params;
+	cmd->i2c_addr = addr;
+
+	memcpy(cmd->i2c_data, data, data_size);
+
+	return ice_aq_send_cmd(hw, &desc, NULL, 0, cd);
+}
+
 /**
  * ice_aq_set_driver_param - Set driver parameter to share via firmware
  * @hw: pointer to the HW struct

drivers/net/ethernet/intel/ice/ice_common.h

@@ -214,5 +214,9 @@ int
 ice_aq_read_i2c(struct ice_hw *hw, struct ice_aqc_link_topo_addr topo_addr,
 		u16 bus_addr, __le16 addr, u8 params, u8 *data,
 		struct ice_sq_cd *cd);
+int
+ice_aq_write_i2c(struct ice_hw *hw, struct ice_aqc_link_topo_addr topo_addr,
+		 u16 bus_addr, __le16 addr, u8 params, u8 *data,
+		 struct ice_sq_cd *cd);
 bool ice_fw_supports_report_dflt_cfg(struct ice_hw *hw);
 #endif /* _ICE_COMMON_H_ */