[PATCH net-next v4] net/mlx5: Expose serial numbers in devlink info

[Jiri Pirko <jiri@resnulli.us>]

From: Jiri Pirko <jiri@nvidia.com>

Devlink info allows to expose serial number and board serial number
Get the values from PCI VPD and expose it.

$ devlink dev info
pci/0000:08:00.0:
  driver mlx5_core
  serial_number e4397f872caeed218000846daa7d2f49
  board.serial_number MT2314XZ00YA
  versions:
      fixed:
        fw.psid MT_0000000894
      running:
        fw.version 28.41.1000
        fw 28.41.1000
      stored:
        fw.version 28.41.1000
        fw 28.41.1000
auxiliary/mlx5_core.eth.0:
  driver mlx5_core.eth
pci/0000:08:00.1:
  driver mlx5_core
  serial_number e4397f872caeed218000846daa7d2f49
  board.serial_number MT2314XZ00YA
  versions:
      fixed:
        fw.psid MT_0000000894
      running:
        fw.version 28.41.1000
        fw 28.41.1000
      stored:
        fw.version 28.41.1000
        fw 28.41.1000
auxiliary/mlx5_core.eth.1:
  driver mlx5_core.eth

Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Parav Pandit <parav@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Acked-by: Tariq Toukan <tariqt@nvidia.com>
---
v3->v4:
- no changes, solo patch, dropped fuid patches
v2->v3:
- do not continue in case devlink_info_*serial_number_put() returns
  error
v1->v2:
- fixed possibly uninitialized variable "err"
---
 .../net/ethernet/mellanox/mlx5/core/devlink.c | 53 +++++++++++++++++++
 1 file changed, 53 insertions(+)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/devlink.c b/drivers/net/ethernet/mellanox/mlx5/core/devlink.c
index 73cd74644378..42218834183a 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/devlink.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/devlink.c
@@ -35,6 +35,55 @@ static u16 mlx5_fw_ver_subminor(u32 version)
 	return version & 0xffff;
 }
 
+static int mlx5_devlink_serial_numbers_put(struct mlx5_core_dev *dev,
+					   struct devlink_info_req *req,
+					   struct netlink_ext_ack *extack)
+{
+	struct pci_dev *pdev = dev->pdev;
+	unsigned int vpd_size, kw_len;
+	char *str, *end;
+	u8 *vpd_data;
+	int err = 0;
+	int start;
+
+	vpd_data = pci_vpd_alloc(pdev, &vpd_size);
+	if (IS_ERR(vpd_data))
+		return 0;
+
+	start = pci_vpd_find_ro_info_keyword(vpd_data, vpd_size,
+					     PCI_VPD_RO_KEYWORD_SERIALNO, &kw_len);
+	if (start >= 0) {
+		str = kstrndup(vpd_data + start, kw_len, GFP_KERNEL);
+		if (!str) {
+			err = -ENOMEM;
+			goto end;
+		}
+		end = strchrnul(str, ' ');
+		*end = '\0';
+		err = devlink_info_board_serial_number_put(req, str);
+		kfree(str);
+		if (err)
+			goto end;
+	}
+
+	start = pci_vpd_find_ro_info_keyword(vpd_data, vpd_size, "V3", &kw_len);
+	if (start >= 0) {
+		str = kstrndup(vpd_data + start, kw_len, GFP_KERNEL);
+		if (!str) {
+			err = -ENOMEM;
+			goto end;
+		}
+		err = devlink_info_serial_number_put(req, str);
+		kfree(str);
+		if (err)
+			goto end;
+	}
+
+end:
+	kfree(vpd_data);
+	return err;
+}
+
 #define DEVLINK_FW_STRING_LEN 32
 
 static int
@@ -49,6 +98,10 @@ mlx5_devlink_info_get(struct devlink *devlink, struct devlink_info_req *req,
 	if (!mlx5_core_is_pf(dev))
 		return 0;
 
+	err = mlx5_devlink_serial_numbers_put(dev, req, extack);
+	if (err)
+		return err;
+
 	err = devlink_info_version_fixed_put(req, "fw.psid", dev->board_id);
 	if (err)
 		return err;
-- 
2.49.0