bnxt_en: Add hwmon sysfs support to read temperature

Export temperature sensor reading via hwmon sysfs.

Signed-off-by: Vasundhara Volam <vasundhara-v.volam@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 71 insertions, 0 deletions

diff --git a/drivers/net/ethernet/broadcom/Kconfig b/drivers/net/ethernet/broadcom/Kconfig
index b7aa8ad96dfb..c1d3ee9baf7e 100644
--- a/drivers/net/ethernet/broadcom/Kconfig
+++ b/drivers/net/ethernet/broadcom/Kconfig
@@ -230,4 +230,12 @@ config BNXT_DCB
 
           If unsure, say N.
 
+config BNXT_HWMON
+        bool "Broadcom NetXtreme-C/E HWMON support"
+        default y
+        depends on BNXT && HWMON && !(BNXT=y && HWMON=m)
+        ---help---
+          Say Y if you want to expose the thermal sensor data on NetXtreme-C/E
+          devices, via the hwmon sysfs interface.
+
 endif # NET_VENDOR_BROADCOM
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index 56bd09758e22..dde904bccab9 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -51,6 +51,8 @@
 #include <linux/cpu_rmap.h>
 #include <linux/cpumask.h>
 #include <net/pkt_cls.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
 
 #include "bnxt_hsi.h"
 #include "bnxt.h"
@@ -6789,6 +6791,62 @@ static void bnxt_get_wol_settings(struct bnxt *bp)
         } while (handle && handle != 0xffff);
 }
 
+#ifdef CONFIG_BNXT_HWMON
+static ssize_t bnxt_show_temp(struct device *dev,
+                              struct device_attribute *devattr, char *buf)
+{
+        struct hwrm_temp_monitor_query_input req = {0};
+        struct hwrm_temp_monitor_query_output *resp;
+        struct bnxt *bp = dev_get_drvdata(dev);
+        u32 temp = 0;
+
+        resp = bp->hwrm_cmd_resp_addr;
+        bnxt_hwrm_cmd_hdr_init(bp, &req, HWRM_TEMP_MONITOR_QUERY, -1, -1);
+        mutex_lock(&bp->hwrm_cmd_lock);
+        if (!_hwrm_send_message(bp, &req, sizeof(req), HWRM_CMD_TIMEOUT))
+                temp = resp->temp * 1000; /* display millidegree */
+        mutex_unlock(&bp->hwrm_cmd_lock);
+
+        return sprintf(buf, "%u\n", temp);
+}
+static SENSOR_DEVICE_ATTR(temp1_input, 0444, bnxt_show_temp, NULL, 0);
+
+static struct attribute *bnxt_attrs[] = {
+        &sensor_dev_attr_temp1_input.dev_attr.attr,
+        NULL
+};
+ATTRIBUTE_GROUPS(bnxt);
+
+static void bnxt_hwmon_close(struct bnxt *bp)
+{
+        if (bp->hwmon_dev) {
+                hwmon_device_unregister(bp->hwmon_dev);
+                bp->hwmon_dev = NULL;
+        }
+}
+
+static void bnxt_hwmon_open(struct bnxt *bp)
+{
+        struct pci_dev *pdev = bp->pdev;
+
+        bp->hwmon_dev = hwmon_device_register_with_groups(&pdev->dev,
+                                                          DRV_MODULE_NAME, bp,
+                                                          bnxt_groups);
+        if (IS_ERR(bp->hwmon_dev)) {
+                bp->hwmon_dev = NULL;
+                dev_warn(&pdev->dev, "Cannot register hwmon device\n");
+        }
+}
+#else
+static void bnxt_hwmon_close(struct bnxt *bp)
+{
+}
+
+static void bnxt_hwmon_open(struct bnxt *bp)
+{
+}
+#endif
+
 static bool bnxt_eee_config_ok(struct bnxt *bp)
 {
         struct ethtool_eee *eee = &bp->eee;
@@ -7040,6 +7098,9 @@ static int bnxt_open(struct net_device *dev)
         rc = __bnxt_open_nic(bp, true, true);
         if (rc)
                 bnxt_hwrm_if_change(bp, false);
+
+        bnxt_hwmon_open(bp);
+
         return rc;
 }
 
@@ -7102,6 +7163,7 @@ static int bnxt_close(struct net_device *dev)
 {
         struct bnxt *bp = netdev_priv(dev);
 
+        bnxt_hwmon_close(bp);
         bnxt_close_nic(bp, true, true);
         bnxt_hwrm_shutdown_link(bp);
         bnxt_hwrm_if_change(bp, false);
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.h b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
index 6c40b25716d3..006726c02f51 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.h
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
@@ -1411,6 +1411,7 @@ struct bnxt {
         struct bnxt_tc_info     *tc_info;
         struct dentry           *debugfs_pdev;
         struct dentry           *debugfs_dim;
+        struct device           *hwmon_dev;
 };
 
 #define BNXT_RX_STATS_OFFSET(counter)                   \