3 files changed, 206 insertions, 1 deletions

diff --git a/drivers/ntb/hw/idt/Kconfig b/drivers/ntb/hw/idt/Kconfig
index b360e5613b9f..2ed147368fa8 100644
--- a/drivers/ntb/hw/idt/Kconfig
+++ b/drivers/ntb/hw/idt/Kconfig
@@ -1,6 +1,7 @@
 config NTB_IDT
         tristate "IDT PCIe-switch Non-Transparent Bridge support"
         depends on PCI
+        select HWMON
         help
          This driver supports NTB of cappable IDT PCIe-switches.
 
diff --git a/drivers/ntb/hw/idt/ntb_hw_idt.c b/drivers/ntb/hw/idt/ntb_hw_idt.c
index adb71f7c1043..19425a2c60cd 100644
--- a/drivers/ntb/hw/idt/ntb_hw_idt.c
+++ b/drivers/ntb/hw/idt/ntb_hw_idt.c
@@ -49,11 +49,14 @@
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/spinlock.h>
+#include <linux/mutex.h>
 #include <linux/pci.h>
 #include <linux/aer.h>
 #include <linux/slab.h>
 #include <linux/list.h>
 #include <linux/debugfs.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
 #include <linux/ntb.h>
 
 #include "ntb_hw_idt.h"
@@ -1925,6 +1928,153 @@ static void idt_read_temp(struct idt_ntb_dev *ndev,
 }
 
 /*
+ * idt_write_temp() - write temperature to the chip sensor register
+ * @ntb:        NTB device context.
+ * @type:       IN - type of the temperature value to change
+ * @val:        IN - integer value of temperature in millidegree Celsius
+ */
+static void idt_write_temp(struct idt_ntb_dev *ndev,
+                           const enum idt_temp_val type, const long val)
+{
+        unsigned int reg;
+        u32 data;
+        u8 fmt;
+
+        /* Retrieve the properly formatted temperature value */
+        fmt = idt_temp_get_fmt(val);
+
+        mutex_lock(&ndev->hwmon_mtx);
+        switch (type) {
+        case IDT_TEMP_LOW:
+                reg = IDT_SW_TMPALARM;
+                data = SET_FIELD(TMPALARM_LTEMP, idt_sw_read(ndev, reg), fmt) &
+                        ~IDT_TMPALARM_IRQ_MASK;
+                break;
+        case IDT_TEMP_HIGH:
+                reg = IDT_SW_TMPALARM;
+                data = SET_FIELD(TMPALARM_HTEMP, idt_sw_read(ndev, reg), fmt) &
+                        ~IDT_TMPALARM_IRQ_MASK;
+                break;
+        case IDT_TEMP_OFFSET:
+                reg = IDT_SW_TMPADJ;
+                data = SET_FIELD(TMPADJ_OFFSET, idt_sw_read(ndev, reg), fmt);
+                break;
+        default:
+                goto inval_spin_unlock;
+        }
+
+        idt_sw_write(ndev, reg, data);
+
+inval_spin_unlock:
+        mutex_unlock(&ndev->hwmon_mtx);
+}
+
+/*
+ * idt_sysfs_show_temp() - printout corresponding temperature value
+ * @dev:        Pointer to the NTB device structure
+ * @da:         Sensor device attribute structure
+ * @buf:        Buffer to print temperature out
+ *
+ * Return: Number of written symbols or negative error
+ */
+static ssize_t idt_sysfs_show_temp(struct device *dev,
+                                   struct device_attribute *da, char *buf)
+{
+        struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+        struct idt_ntb_dev *ndev = dev_get_drvdata(dev);
+        enum idt_temp_val type = attr->index;
+        long mdeg;
+
+        idt_read_temp(ndev, type, &mdeg);
+        return sprintf(buf, "%ld\n", mdeg);
+}
+
+/*
+ * idt_sysfs_set_temp() - set corresponding temperature value
+ * @dev:        Pointer to the NTB device structure
+ * @da:         Sensor device attribute structure
+ * @buf:        Buffer to print temperature out
+ * @count:      Size of the passed buffer
+ *
+ * Return: Number of written symbols or negative error
+ */
+static ssize_t idt_sysfs_set_temp(struct device *dev,
+                                  struct device_attribute *da, const char *buf,
+                                  size_t count)
+{
+        struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+        struct idt_ntb_dev *ndev = dev_get_drvdata(dev);
+        enum idt_temp_val type = attr->index;
+        long mdeg;
+        int ret;
+
+        ret = kstrtol(buf, 10, &mdeg);
+        if (ret)
+                return ret;
+
+        /* Clamp the passed value in accordance with the type */
+        if (type == IDT_TEMP_OFFSET)
+                mdeg = clamp_val(mdeg, IDT_TEMP_MIN_OFFSET,
+                                 IDT_TEMP_MAX_OFFSET);
+        else
+                mdeg = clamp_val(mdeg, IDT_TEMP_MIN_MDEG, IDT_TEMP_MAX_MDEG);
+
+        idt_write_temp(ndev, type, mdeg);
+
+        return count;
+}
+
+/*
+ * idt_sysfs_reset_hist() - reset temperature history
+ * @dev:        Pointer to the NTB device structure
+ * @da:         Sensor device attribute structure
+ * @buf:        Buffer to print temperature out
+ * @count:      Size of the passed buffer
+ *
+ * Return: Number of written symbols or negative error
+ */
+static ssize_t idt_sysfs_reset_hist(struct device *dev,
+                                    struct device_attribute *da,
+                                    const char *buf, size_t count)
+{
+        struct idt_ntb_dev *ndev = dev_get_drvdata(dev);
+
+        /* Just set the maximal value to the lowest temperature field and
+         * minimal value to the highest temperature field
+         */
+        idt_write_temp(ndev, IDT_TEMP_LOW, IDT_TEMP_MAX_MDEG);
+        idt_write_temp(ndev, IDT_TEMP_HIGH, IDT_TEMP_MIN_MDEG);
+
+        return count;
+}
+
+/*
+ * Hwmon IDT sysfs attributes
+ */
+static SENSOR_DEVICE_ATTR(temp1_input, 0444, idt_sysfs_show_temp, NULL,
+                          IDT_TEMP_CUR);
+static SENSOR_DEVICE_ATTR(temp1_lowest, 0444, idt_sysfs_show_temp, NULL,
+                          IDT_TEMP_LOW);
+static SENSOR_DEVICE_ATTR(temp1_highest, 0444, idt_sysfs_show_temp, NULL,
+                          IDT_TEMP_HIGH);
+static SENSOR_DEVICE_ATTR(temp1_offset, 0644, idt_sysfs_show_temp,
+                          idt_sysfs_set_temp, IDT_TEMP_OFFSET);
+static DEVICE_ATTR(temp1_reset_history, 0200, NULL, idt_sysfs_reset_hist);
+
+/*
+ * Hwmon IDT sysfs attributes group
+ */
+static struct attribute *idt_temp_attrs[] = {
+        &sensor_dev_attr_temp1_input.dev_attr.attr,
+        &sensor_dev_attr_temp1_lowest.dev_attr.attr,
+        &sensor_dev_attr_temp1_highest.dev_attr.attr,
+        &sensor_dev_attr_temp1_offset.dev_attr.attr,
+        &dev_attr_temp1_reset_history.attr,
+        NULL
+};
+ATTRIBUTE_GROUPS(idt_temp);
+
+/*
  * idt_temp_isr() - temperature sensor alarm events ISR
  * @ndev:       IDT NTB hardware driver descriptor
  * @ntint_sts:  NT-function interrupt status
@@ -1956,6 +2106,35 @@ static void idt_temp_isr(struct idt_ntb_dev *ndev, u32 ntint_sts)
                 idt_get_deg(mdeg), idt_get_deg_frac(mdeg));
 }
 
+/*
+ * idt_init_temp() - initialize temperature sensor interface
+ * @ndev:       IDT NTB hardware driver descriptor
+ *
+ * Simple sensor initializarion method is responsible for device switching
+ * on and resource management based hwmon interface registration. Note, that
+ * since the device is shared we won't disable it on remove, but leave it
+ * working until the system is powered off.
+ */
+static void idt_init_temp(struct idt_ntb_dev *ndev)
+{
+        struct device *hwmon;
+
+        /* Enable sensor if it hasn't been already */
+        idt_sw_write(ndev, IDT_SW_TMPCTL, 0x0);
+
+        /* Initialize hwmon interface fields */
+        mutex_init(&ndev->hwmon_mtx);
+
+        hwmon = devm_hwmon_device_register_with_groups(&ndev->ntb.pdev->dev,
+                ndev->swcfg->name, ndev, idt_temp_groups);
+        if (IS_ERR(hwmon)) {
+                dev_err(&ndev->ntb.pdev->dev, "Couldn't create hwmon device");
+                return;
+        }
+
+        dev_dbg(&ndev->ntb.pdev->dev, "Temperature HWmon interface registered");
+}
+
 /*=============================================================================
  *                           8. ISRs related operations
  *
@@ -2650,6 +2829,9 @@ static int idt_pci_probe(struct pci_dev *pdev,
         /* Initialize Messaging subsystem */
         idt_init_msg(ndev);
 
+        /* Initialize hwmon interface */
+        idt_init_temp(ndev);
+
         /* Initialize IDT interrupts handler */
         ret = idt_init_isr(ndev);
         if (ret != 0)
diff --git a/drivers/ntb/hw/idt/ntb_hw_idt.h b/drivers/ntb/hw/idt/ntb_hw_idt.h
index 9dfd6b11a621..032f81cb4d44 100644
--- a/drivers/ntb/hw/idt/ntb_hw_idt.h
+++ b/drivers/ntb/hw/idt/ntb_hw_idt.h
@@ -47,9 +47,9 @@
 #include <linux/pci_ids.h>
 #include <linux/interrupt.h>
 #include <linux/spinlock.h>
+#include <linux/mutex.h>
 #include <linux/ntb.h>
 
-
 /*
  * Macro is used to create the struct pci_device_id that matches
  * the supported IDT PCIe-switches
@@ -907,6 +907,10 @@
  * TMPSTS register fields related constants
  * @IDT_TMPSTS_TEMP_MASK:       Current temperature field mask
  * @IDT_TMPSTS_TEMP_FLD:        Current temperature field offset
+ * @IDT_TMPSTS_LTEMP_MASK:      Lowest temperature field mask
+ * @IDT_TMPSTS_LTEMP_FLD:       Lowest temperature field offset
+ * @IDT_TMPSTS_HTEMP_MASK:      Highest temperature field mask
+ * @IDT_TMPSTS_HTEMP_FLD:       Highest temperature field offset
  */
 #define IDT_TMPSTS_TEMP_MASK            0x000000FFU
 #define IDT_TMPSTS_TEMP_FLD             0
@@ -916,6 +920,20 @@
 #define IDT_TMPSTS_HTEMP_FLD            16
 
 /*
+ * TMPALARM register fields related constants
+ * @IDT_TMPALARM_LTEMP_MASK:    Lowest temperature field mask
+ * @IDT_TMPALARM_LTEMP_FLD:     Lowest temperature field offset
+ * @IDT_TMPALARM_HTEMP_MASK:    Highest temperature field mask
+ * @IDT_TMPALARM_HTEMP_FLD:     Highest temperature field offset
+ * @IDT_TMPALARM_IRQ_MASK:      Alarm IRQ status mask
+ */
+#define IDT_TMPALARM_LTEMP_MASK         0x0000FF00U
+#define IDT_TMPALARM_LTEMP_FLD          8
+#define IDT_TMPALARM_HTEMP_MASK         0x00FF0000U
+#define IDT_TMPALARM_HTEMP_FLD          16
+#define IDT_TMPALARM_IRQ_MASK           0x3F000000U
+
+/*
  * TMPADJ register fields related constants
  * @IDT_TMPADJ_OFFSET_MASK:     Temperature value offset field mask
  * @IDT_TMPADJ_OFFSET_FLD:      Temperature value offset field offset
@@ -1100,6 +1118,8 @@ struct idt_ntb_peer {
  * @msg_mask_lock:      Message mask register lock
  * @gasa_lock:          GASA registers access lock
  *
+ * @hwmon_mtx:          Temperature sensor interface update mutex
+ *
  * @dbgfs_info:         DebugFS info node
  */
 struct idt_ntb_dev {
@@ -1127,6 +1147,8 @@ struct idt_ntb_dev {
         spinlock_t msg_mask_lock;
         spinlock_t gasa_lock;
 
+        struct mutex hwmon_mtx;
+
         struct dentry *dbgfs_info;
 };
 #define to_ndev_ntb(__ntb) container_of(__ntb, struct idt_ntb_dev, ntb)