ice: add TTY for GNSS module for E810T device

Add a new ice_gnss.c file for holding the basic GNSS module functions.
If the device supports GNSS module, call the new ice_gnss_init and
ice_gnss_release functions where appropriate.

Implement basic functionality for reading the data from GNSS module
using TTY device.

Add I2C read AQ command. It is now required for controlling the external
physical connectors via external I2C port expander on E810-T adapters.

Future changes will introduce write functionality.

Signed-off-by: Karol Kolacinski <karol.kolacinski@intel.com>
Signed-off-by: Sudhansu Sekhar Mishra <sudhansu.mishra@intel.com>
Tested-by: Sunitha Mekala <sunithax.d.mekala@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/intel/ice/Makefile

@@ -40,6 +40,7 @@ ice-$(CONFIG_PCI_IOV) +=	\
 	ice_vf_vsi_vlan_ops.o	\
 	ice_virtchnl_pf.o
 ice-$(CONFIG_PTP_1588_CLOCK) += ice_ptp.o ice_ptp_hw.o
+ice-$(CONFIG_TTY) += ice_gnss.o
 ice-$(CONFIG_DCB) += ice_dcb.o ice_dcb_nl.o ice_dcb_lib.o
 ice-$(CONFIG_RFS_ACCEL) += ice_arfs.o
 ice-$(CONFIG_XDP_SOCKETS) += ice_xsk.o

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

@@ -73,6 +73,7 @@
 #include "ice_eswitch.h"
 #include "ice_lag.h"
 #include "ice_vsi_vlan_ops.h"
+#include "ice_gnss.h"
 
 #define ICE_BAR0		0
 #define ICE_REQ_DESC_MULTIPLE	32
@@ -184,6 +185,7 @@
 enum ice_feature {
 	ICE_F_DSCP,
 	ICE_F_SMA_CTRL,
+	ICE_F_GNSS,
 	ICE_F_MAX
 };
 
@@ -486,6 +488,7 @@ enum ice_pf_flags {
 	ICE_FLAG_VF_VLAN_PRUNING,
 	ICE_FLAG_LINK_LENIENT_MODE_ENA,
 	ICE_FLAG_PLUG_AUX_DEV,
+	ICE_FLAG_GNSS,			/* GNSS successfully initialized */
 	ICE_PF_FLAGS_NBITS		/* must be last */
 };
 
@@ -549,6 +552,9 @@ struct ice_pf {
 	struct mutex tc_mutex;		/* lock to protect TC changes */
 	u32 msg_enable;
 	struct ice_ptp ptp;
+	struct tty_driver *ice_gnss_tty_driver;
+	struct tty_port gnss_tty_port;
+	struct gnss_serial *gnss_serial;
 	u16 num_rdma_msix;		/* Total MSIX vectors for RDMA driver */
 	u16 rdma_base_vector;
 

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

@@ -1401,6 +1401,24 @@ struct ice_aqc_get_link_topo {
 	u8 rsvd[9];
 };
 
+/* Read I2C (direct, 0x06E2) */
+struct ice_aqc_i2c {
+	struct ice_aqc_link_topo_addr topo_addr;
+	__le16 i2c_addr;
+	u8 i2c_params;
+#define ICE_AQC_I2C_DATA_SIZE_M		GENMASK(3, 0)
+#define ICE_AQC_I2C_USE_REPEATED_START	BIT(7)
+
+	u8 rsvd;
+	__le16 i2c_bus_addr;
+	u8 rsvd2[4];
+};
+
+/* Read I2C Response (direct, 0x06E2) */
+struct ice_aqc_read_i2c_resp {
+	u8 i2c_data[16];
+};
+
 /* Set Port Identification LED (direct, 0x06E9) */
 struct ice_aqc_set_port_id_led {
 	u8 lport_num;
@@ -2112,6 +2130,8 @@ 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_read_i2c_resp read_i2c_resp;
 	} params;
 };
 
@@ -2226,6 +2246,7 @@ enum ice_adminq_opc {
 	ice_aqc_opc_set_event_mask			= 0x0613,
 	ice_aqc_opc_set_mac_lb				= 0x0620,
 	ice_aqc_opc_get_link_topo			= 0x06E0,
+	ice_aqc_opc_read_i2c				= 0x06E2,
 	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

@@ -4797,6 +4797,59 @@ ice_sched_query_elem(struct ice_hw *hw, u32 node_teid,
 	return status;
 }
 
+/**
+ * ice_aq_read_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 [7] - Repeated start,
+ *			    bits [6:5] data offset size,
+ *			    bit [4] - I2C address type,
+ *			    bits [3:0] - data size to read (0-16 bytes)
+ * @data: pointer to data (0 to 16 bytes) to be read from the I2C device
+ * @cd: pointer to command details structure or NULL
+ *
+ * Read I2C (0x06E2)
+ */
+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)
+{
+	struct ice_aq_desc desc = { 0 };
+	struct ice_aqc_i2c *cmd;
+	u8 data_size;
+	int status;
+
+	ice_fill_dflt_direct_cmd_desc(&desc, ice_aqc_opc_read_i2c);
+	cmd = &desc.params.read_i2c;
+
+	if (!data)
+		return -EINVAL;
+
+	data_size = FIELD_GET(ICE_AQC_I2C_DATA_SIZE_M, params);
+
+	cmd->i2c_bus_addr = cpu_to_le16(bus_addr);
+	cmd->topo_addr = topo_addr;
+	cmd->i2c_params = params;
+	cmd->i2c_addr = addr;
+
+	status = ice_aq_send_cmd(hw, &desc, NULL, 0, cd);
+	if (!status) {
+		struct ice_aqc_read_i2c_resp *resp;
+		u8 i;
+
+		resp = &desc.params.read_i2c_resp;
+		for (i = 0; i < data_size; i++) {
+			*data = resp->i2c_data[i];
+			data++;
+		}
+	}
+
+	return status;
+}
+
 /**
  * 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

@@ -4,6 +4,8 @@
 #ifndef _ICE_COMMON_H_
 #define _ICE_COMMON_H_
 
+#include <linux/bitfield.h>
+
 #include "ice.h"
 #include "ice_type.h"
 #include "ice_nvm.h"
@@ -208,5 +210,9 @@ ice_aq_set_lldp_mib(struct ice_hw *hw, u8 mib_type, void *buf, u16 buf_size,
 bool ice_fw_supports_lldp_fltr_ctrl(struct ice_hw *hw);
 int
 ice_lldp_fltr_add_remove(struct ice_hw *hw, u16 vsi_num, bool add);
+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);
 bool ice_fw_supports_report_dflt_cfg(struct ice_hw *hw);
 #endif /* _ICE_COMMON_H_ */