[PATCH v3 net-next 4/8] mfd: zl3073x: Add support for devlink device info

Ivan Vecera
2025-04-16T16:22:21Z

Use devlink_alloc() to alloc zl3073x_dev structure, register the device
as a devlink device and add devlink callback to provide devlink device
info.

Signed-off-by: Ivan Vecera <ivecera@redhat.com>
---
v2->v3:
* merged devlink device allocation, registration and device info
callback

v1->v2:
- dependency on NET moved to MFD_ZL3073X_CORE in Kconfig
- devlink register managed way
---
drivers/mfd/Kconfig | 2 +
drivers/mfd/zl3073x-core.c | 106 ++++++++++++++++++++++++++++++++++++-
2 files changed, 106 insertions(+), 2 deletions(-)

diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 7d7902ec1d89a..e4eca15af175d 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -2424,6 +2424,8 @@ config MFD_UPBOARD_FPGA

config MFD_ZL3073X_CORE
tristate
+ depends on NET
+ select NET_DEVLINK
select MFD_CORE

config MFD_ZL3073X_I2C
diff --git a/drivers/mfd/zl3073x-core.c b/drivers/mfd/zl3073x-core.c
index 0455d6ae37da5..8a15237e0f731 100644
--- a/drivers/mfd/zl3073x-core.c
+++ b/drivers/mfd/zl3073x-core.c
@@ -8,7 +8,10 @@
#include <linux/mfd/zl3073x.h>
#include <linux/mfd/zl3073x_regs.h>
#include <linux/module.h>
+#include <linux/netlink.h>
#include <linux/regmap.h>
+#include <linux/sprintf.h>
+#include <net/devlink.h>
#include "zl3073x.h"

/* Chip IDs for zl30731 */
@@ -112,6 +115,83 @@ static const struct regmap_config zl3073x_regmap_config = {
.volatile_reg = zl3073x_is_volatile_reg,
};

+/**
+ * zl3073x_devlink_info_get - Devlink device info callback
+ * @devlink: devlink structure pointer
+ * @req: devlink request pointer to store information
+ * @extack: netlink extack pointer to report errors
+ *
+ * Return: 0 on success, <0 on error
+ */
+static int zl3073x_devlink_info_get(struct devlink *devlink,
+ struct devlink_info_req *req,
+ struct netlink_ext_ack *extack)
+{
+ struct zl3073x_dev *zldev = devlink_priv(devlink);
+ u16 id, revision, fw_ver;
+ char buf[16];
+ u32 cfg_ver;
+ int rc;
+
+ rc = zl3073x_read_id(zldev, &id);
+ if (rc)
+ return rc;
+
+ snprintf(buf, sizeof(buf), "%X", id);
+ rc = devlink_info_version_fixed_put(req,
+ DEVLINK_INFO_VERSION_GENERIC_ASIC_ID,
+ buf);
+ if (rc)
+ return rc;
+
+ rc = zl3073x_read_revision(zldev, &revision);
+ if (rc)
+ return rc;
+
+ snprintf(buf, sizeof(buf), "%X", revision);
+ rc = devlink_info_version_fixed_put(req,
+ DEVLINK_INFO_VERSION_GENERIC_ASIC_REV,
+ buf);
+ if (rc)
+ return rc;
+
+ rc = zl3073x_read_fw_ver(zldev, &fw_ver);
+ if (rc)
+ return rc;
+
+ snprintf(buf, sizeof(buf), "%u", fw_ver);
+ rc = devlink_info_version_fixed_put(req,
+ DEVLINK_INFO_VERSION_GENERIC_FW,
+ buf);
+ if (rc)
+ return rc;
+
+ rc = zl3073x_read_custom_config_ver(zldev, &cfg_ver);
+ if (rc)
+ return rc;
+
+ /* No custom config version */
+ if (cfg_ver == U32_MAX)
+ return 0;
+
+ snprintf(buf, sizeof(buf), "%lu.%lu.%lu.%lu",
+ FIELD_GET(GENMASK(31, 24), cfg_ver),
+ FIELD_GET(GENMASK(23, 16), cfg_ver),
+ FIELD_GET(GENMASK(15, 8), cfg_ver),
+ FIELD_GET(GENMASK(7, 0), cfg_ver));
+
+ return devlink_info_version_running_put(req, "cfg.custom_ver", buf);
+}
+
+static const struct devlink_ops zl3073x_devlink_ops = {
+ .info_get = zl3073x_devlink_info_get,
+};
+
+static void zl3073x_devlink_free(void *ptr)
+{
+ devlink_free(ptr);
+}
+
/**
* zl3073x_devm_alloc - allocates zl3073x device structure
* @dev: pointer to device structure
@@ -124,12 +204,18 @@ static const struct regmap_config zl3073x_regmap_config = {
struct zl3073x_dev *zl3073x_devm_alloc(struct device *dev)
{
struct zl3073x_dev *zldev;
+ struct devlink *devlink;
int rc;

- zldev = devm_kzalloc(dev, sizeof(*zldev), GFP_KERNEL);
- if (!zldev)
+ devlink = devlink_alloc(&zl3073x_devlink_ops, sizeof(*zldev), dev);
+ if (!devlink)
return ERR_PTR(-ENOMEM);

+ /* Add devres action to free devlink device */
+ if (devm_add_action_or_reset(dev, zl3073x_devlink_free, devlink))
+ return ERR_PTR(-ENOMEM);
+
+ zldev = devlink_priv(devlink);
zldev->dev = dev;

/* We have to initialize regmap mutex here because during
@@ -158,6 +244,11 @@ void zl3073x_dev_init_regmap_config(struct regmap_config *regmap_cfg)
}
EXPORT_SYMBOL_NS_GPL(zl3073x_dev_init_regmap_config, "ZL3073X");

+static void zl3073x_devlink_unregister(void *ptr)
+{
+ devlink_unregister(ptr);
+}
+
/**
* zl3073x_dev_probe - initialize zl3073x device
* @zldev: pointer to zl3073x device
@@ -171,6 +262,7 @@ int zl3073x_dev_probe(struct zl3073x_dev *zldev,
const struct zl3073x_chip_info *chip_info)
{
u16 id, revision, fw_ver;
+ struct devlink *devlink;
u32 cfg_ver;
int i, rc;

@@ -209,6 +301,16 @@ int zl3073x_dev_probe(struct zl3073x_dev *zldev,
FIELD_GET(GENMASK(15, 8), cfg_ver),
FIELD_GET(GENMASK(7, 0), cfg_ver));

+ /* Register the device as devlink device */
+ devlink = priv_to_devlink(zldev);
+ devlink_register(devlink);
+
+ /* Add devres action to unregister devlink device */
+ rc = devm_add_action_or_reset(zldev->dev, zl3073x_devlink_unregister,
+ devlink);
+ if (rc)
+ return rc;
+
return 0;
}
EXPORT_SYMBOL_NS_GPL(zl3073x_dev_probe, "ZL3073X");
--
2.48.1