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2024-01-03 2f7c68cb55ecb7331f2381deb497c27155f32faf 
 kernel/drivers/ntb/hw/idt/ntb_hw_idt.c
....@@ -4,7 +4,7 @@
44  *
55  *   GPL LICENSE SUMMARY
66  *
7
- *   Copyright (C) 2016 T-Platforms All Rights Reserved.
7
+ *   Copyright (C) 2016-2018 T-Platforms JSC All Rights Reserved.
88  *
99  *   This program is free software; you can redistribute it and/or modify it
1010  *   under the terms and conditions of the GNU General Public License,
....@@ -49,11 +49,14 @@
4949 #include <linux/init.h>
5050 #include <linux/interrupt.h>
5151 #include <linux/spinlock.h>
52
+#include <linux/mutex.h>
5253 #include <linux/pci.h>
5354 #include <linux/aer.h>
5455 #include <linux/slab.h>
5556 #include <linux/list.h>
5657 #include <linux/debugfs.h>
58
+#include <linux/hwmon.h>
59
+#include <linux/hwmon-sysfs.h>
5760 #include <linux/ntb.h>
5861 
5962 #include "ntb_hw_idt.h"
....@@ -355,8 +358,6 @@
355358 	iowrite32((u32)reg, ndev->cfgspc + (ptrdiff_t)IDT_NT_GASAADDR);
356359 	/* Put the new value of the register */
357360 	iowrite32(data, ndev->cfgspc + (ptrdiff_t)IDT_NT_GASADATA);
358
-	/* Make sure the PCIe transactions are executed */
359
-	mmiowb();
360361 	/* Unlock GASA registers operations */
361362 	spin_unlock_irqrestore(&ndev->gasa_lock, irqflags);
362363 }
....@@ -747,7 +748,6 @@
747748 	spin_lock_irqsave(&ndev->mtbl_lock, irqflags);
748749 	idt_nt_write(ndev, IDT_NT_NTMTBLADDR, ndev->part);
749750 	idt_nt_write(ndev, IDT_NT_NTMTBLDATA, mtbldata);
750
-	mmiowb();
751751 	spin_unlock_irqrestore(&ndev->mtbl_lock, irqflags);
752752 
753753 	/* Notify the peers by setting and clearing the global signal bit */
....@@ -775,7 +775,6 @@
775775 	spin_lock_irqsave(&ndev->mtbl_lock, irqflags);
776776 	idt_nt_write(ndev, IDT_NT_NTMTBLADDR, ndev->part);
777777 	idt_nt_write(ndev, IDT_NT_NTMTBLDATA, 0);
778
-	mmiowb();
779778 	spin_unlock_irqrestore(&ndev->mtbl_lock, irqflags);
780779 
781780 	/* Notify the peers by setting and clearing the global signal bit */
....@@ -1320,7 +1319,7 @@
13201319 		idt_nt_write(ndev, bar->ltbase, (u32)addr);
13211320 		idt_nt_write(ndev, bar->utbase, (u32)(addr >> 32));
13221321 		/* Set the custom BAR aperture limit */
1323
-		limit = pci_resource_start(ntb->pdev, mw_cfg->bar) + size;
1322
+		limit = pci_bus_address(ntb->pdev, mw_cfg->bar) + size;
13241323 		idt_nt_write(ndev, bar->limit, (u32)limit);
13251324 		if (IS_FLD_SET(BARSETUP_TYPE, data, 64))
13261325 			idt_nt_write(ndev, (bar + 1)->limit, (limit >> 32));
....@@ -1336,7 +1335,6 @@
13361335 		idt_nt_write(ndev, IDT_NT_LUTLDATA, (u32)addr);
13371336 		idt_nt_write(ndev, IDT_NT_LUTMDATA, (u32)(addr >> 32));
13381337 		idt_nt_write(ndev, IDT_NT_LUTUDATA, data);
1339
-		mmiowb();
13401338 		spin_unlock_irqrestore(&ndev->lut_lock, irqflags);
13411339 		/* Limit address isn't specified since size is fixed for LUT */
13421340 	}
....@@ -1390,7 +1388,6 @@
13901388 		idt_nt_write(ndev, IDT_NT_LUTLDATA, 0);
13911389 		idt_nt_write(ndev, IDT_NT_LUTMDATA, 0);
13921390 		idt_nt_write(ndev, IDT_NT_LUTUDATA, 0);
1393
-		mmiowb();
13941391 		spin_unlock_irqrestore(&ndev->lut_lock, irqflags);
13951392 	}
13961393 
....@@ -1809,7 +1806,6 @@
18091806 	/* Set the route and send the data */
18101807 	idt_sw_write(ndev, partdata_tbl[ndev->part].msgctl[midx], swpmsgctl);
18111808 	idt_nt_write(ndev, ntdata_tbl.msgs[midx].out, msg);
1812
-	mmiowb();
18131809 	/* Unlock the messages routing table */
18141810 	spin_unlock_irqrestore(&ndev->msg_locks[midx], irqflags);
18151811 
....@@ -1821,61 +1817,284 @@
18211817  *                      7. Temperature sensor operations
18221818  *
18231819  *    IDT PCIe-switch has an embedded temperature sensor, which can be used to
1824
- * warn a user-space of possible chip overheating. Since workload temperature
1825
- * can be different on different platforms, temperature thresholds as well as
1826
- * general sensor settings must be setup in the framework of BIOS/EEPROM
1827
- * initializations. It includes the actual sensor enabling as well.
1820
+ * check current chip core temperature. Since a workload environment can be
1821
+ * different on different platforms, an offset and ADC/filter settings can be
1822
+ * specified. Although the offset configuration is only exposed to the sysfs
1823
+ * hwmon interface at the moment. The rest of the settings can be adjusted
1824
+ * for instance by the BIOS/EEPROM firmware.
18281825  *=============================================================================
18291826  */
18301827 
18311828 /*
1832
- * idt_read_temp() - read temperature from chip sensor
1833
- * @ntb:	NTB device context.
1834
- * @val:	OUT - integer value of temperature
1835
- * @frac:	OUT - fraction
1829
+ * idt_get_deg() - convert millidegree Celsius value to just degree
1830
+ * @mdegC:	IN - millidegree Celsius value
1831
+ *
1832
+ * Return: Degree corresponding to the passed millidegree value
18361833  */
1837
-static void idt_read_temp(struct idt_ntb_dev *ndev, unsigned char *val,
1838
-			  unsigned char *frac)
1834
+static inline s8 idt_get_deg(long mdegC)
18391835 {
1840
-	u32 data;
1841
-
1842
-	/* Read the data from TEMP field of the TMPSTS register */
1843
-	data = idt_sw_read(ndev, IDT_SW_TMPSTS);
1844
-	data = GET_FIELD(TMPSTS_TEMP, data);
1845
-	/* TEMP field has one fractional bit and seven integer bits */
1846
-	*val = data >> 1;
1847
-	*frac = ((data & 0x1) ? 5 : 0);
1836
+	return mdegC / 1000;
18481837 }
18491838 
18501839 /*
1851
- * idt_temp_isr() - temperature sensor alarm events ISR
1852
- * @ndev:	IDT NTB hardware driver descriptor
1853
- * @ntint_sts:	NT-function interrupt status
1840
+ * idt_get_frac() - retrieve 0/0.5 fraction of the millidegree Celsius value
1841
+ * @mdegC:	IN - millidegree Celsius value
18541842  *
1855
- * It handles events of temperature crossing alarm thresholds. Since reading
1856
- * of TMPALARM register clears it up, the function doesn't analyze the
1857
- * read value, instead the current temperature value just warningly printed to
1858
- * log.
1859
- * The method is called from PCIe ISR bottom-half routine.
1843
+ * Return: 0/0.5 degree fraction of the passed millidegree value
18601844  */
1861
-static void idt_temp_isr(struct idt_ntb_dev *ndev, u32 ntint_sts)
1845
+static inline u8 idt_get_deg_frac(long mdegC)
18621846 {
1863
-	unsigned char val, frac;
1847
+	return (mdegC % 1000) >= 500 ? 5 : 0;
1848
+}
18641849 
1865
-	/* Read the current temperature value */
1866
-	idt_read_temp(ndev, &val, &frac);
1850
+/*
1851
+ * idt_get_temp_fmt() - convert millidegree Celsius value to 0:7:1 format
1852
+ * @mdegC:	IN - millidegree Celsius value
1853
+ *
1854
+ * Return: 0:7:1 format acceptable by the IDT temperature sensor
1855
+ */
1856
+static inline u8 idt_temp_get_fmt(long mdegC)
1857
+{
1858
+	return (idt_get_deg(mdegC) << 1) | (idt_get_deg_frac(mdegC) ? 1 : 0);
1859
+}
18671860 
1868
-	/* Read the temperature alarm to clean the alarm status out */
1869
-	/*(void)idt_sw_read(ndev, IDT_SW_TMPALARM);*/
1861
+/*
1862
+ * idt_get_temp_sval() - convert temp sample to signed millidegree Celsius
1863
+ * @data:	IN - shifted to LSB 8-bits temperature sample
1864
+ *
1865
+ * Return: signed millidegree Celsius
1866
+ */
1867
+static inline long idt_get_temp_sval(u32 data)
1868
+{
1869
+	return ((s8)data / 2) * 1000 + (data & 0x1 ? 500 : 0);
1870
+}
18701871 
1871
-	/* Clean the corresponding interrupt bit */
1872
-	idt_nt_write(ndev, IDT_NT_NTINTSTS, IDT_NTINTSTS_TMPSENSOR);
1872
+/*
1873
+ * idt_get_temp_sval() - convert temp sample to unsigned millidegree Celsius
1874
+ * @data:	IN - shifted to LSB 8-bits temperature sample
1875
+ *
1876
+ * Return: unsigned millidegree Celsius
1877
+ */
1878
+static inline long idt_get_temp_uval(u32 data)
1879
+{
1880
+	return (data / 2) * 1000 + (data & 0x1 ? 500 : 0);
1881
+}
18731882 
1874
-	dev_dbg(&ndev->ntb.pdev->dev,
1875
-		"Temp sensor IRQ detected %#08x", ntint_sts);
1883
+/*
1884
+ * idt_read_temp() - read temperature from chip sensor
1885
+ * @ntb:	NTB device context.
1886
+ * @type:	IN - type of the temperature value to read
1887
+ * @val:	OUT - integer value of temperature in millidegree Celsius
1888
+ */
1889
+static void idt_read_temp(struct idt_ntb_dev *ndev,
1890
+			  const enum idt_temp_val type, long *val)
1891
+{
1892
+	u32 data;
18761893 
1877
-	/* Print temperature value to log */
1878
-	dev_warn(&ndev->ntb.pdev->dev, "Temperature %hhu.%hhu", val, frac);
1894
+	/* Alter the temperature field in accordance with the passed type */
1895
+	switch (type) {
1896
+	case IDT_TEMP_CUR:
1897
+		data = GET_FIELD(TMPSTS_TEMP,
1898
+				 idt_sw_read(ndev, IDT_SW_TMPSTS));
1899
+		break;
1900
+	case IDT_TEMP_LOW:
1901
+		data = GET_FIELD(TMPSTS_LTEMP,
1902
+				 idt_sw_read(ndev, IDT_SW_TMPSTS));
1903
+		break;
1904
+	case IDT_TEMP_HIGH:
1905
+		data = GET_FIELD(TMPSTS_HTEMP,
1906
+				 idt_sw_read(ndev, IDT_SW_TMPSTS));
1907
+		break;
1908
+	case IDT_TEMP_OFFSET:
1909
+		/* This is the only field with signed 0:7:1 format */
1910
+		data = GET_FIELD(TMPADJ_OFFSET,
1911
+				 idt_sw_read(ndev, IDT_SW_TMPADJ));
1912
+		*val = idt_get_temp_sval(data);
1913
+		return;
1914
+	default:
1915
+		data = GET_FIELD(TMPSTS_TEMP,
1916
+				 idt_sw_read(ndev, IDT_SW_TMPSTS));
1917
+		break;
1918
+	}
1919
+
1920
+	/* The rest of the fields accept unsigned 0:7:1 format */
1921
+	*val = idt_get_temp_uval(data);
1922
+}
1923
+
1924
+/*
1925
+ * idt_write_temp() - write temperature to the chip sensor register
1926
+ * @ntb:	NTB device context.
1927
+ * @type:	IN - type of the temperature value to change
1928
+ * @val:	IN - integer value of temperature in millidegree Celsius
1929
+ */
1930
+static void idt_write_temp(struct idt_ntb_dev *ndev,
1931
+			   const enum idt_temp_val type, const long val)
1932
+{
1933
+	unsigned int reg;
1934
+	u32 data;
1935
+	u8 fmt;
1936
+
1937
+	/* Retrieve the properly formatted temperature value */
1938
+	fmt = idt_temp_get_fmt(val);
1939
+
1940
+	mutex_lock(&ndev->hwmon_mtx);
1941
+	switch (type) {
1942
+	case IDT_TEMP_LOW:
1943
+		reg = IDT_SW_TMPALARM;
1944
+		data = SET_FIELD(TMPALARM_LTEMP, idt_sw_read(ndev, reg), fmt) &
1945
+			~IDT_TMPALARM_IRQ_MASK;
1946
+		break;
1947
+	case IDT_TEMP_HIGH:
1948
+		reg = IDT_SW_TMPALARM;
1949
+		data = SET_FIELD(TMPALARM_HTEMP, idt_sw_read(ndev, reg), fmt) &
1950
+			~IDT_TMPALARM_IRQ_MASK;
1951
+		break;
1952
+	case IDT_TEMP_OFFSET:
1953
+		reg = IDT_SW_TMPADJ;
1954
+		data = SET_FIELD(TMPADJ_OFFSET, idt_sw_read(ndev, reg), fmt);
1955
+		break;
1956
+	default:
1957
+		goto inval_spin_unlock;
1958
+	}
1959
+
1960
+	idt_sw_write(ndev, reg, data);
1961
+
1962
+inval_spin_unlock:
1963
+	mutex_unlock(&ndev->hwmon_mtx);
1964
+}
1965
+
1966
+/*
1967
+ * idt_sysfs_show_temp() - printout corresponding temperature value
1968
+ * @dev:	Pointer to the NTB device structure
1969
+ * @da:		Sensor device attribute structure
1970
+ * @buf:	Buffer to print temperature out
1971
+ *
1972
+ * Return: Number of written symbols or negative error
1973
+ */
1974
+static ssize_t idt_sysfs_show_temp(struct device *dev,
1975
+				   struct device_attribute *da, char *buf)
1976
+{
1977
+	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
1978
+	struct idt_ntb_dev *ndev = dev_get_drvdata(dev);
1979
+	enum idt_temp_val type = attr->index;
1980
+	long mdeg;
1981
+
1982
+	idt_read_temp(ndev, type, &mdeg);
1983
+	return sprintf(buf, "%ld\n", mdeg);
1984
+}
1985
+
1986
+/*
1987
+ * idt_sysfs_set_temp() - set corresponding temperature value
1988
+ * @dev:	Pointer to the NTB device structure
1989
+ * @da:		Sensor device attribute structure
1990
+ * @buf:	Buffer to print temperature out
1991
+ * @count:	Size of the passed buffer
1992
+ *
1993
+ * Return: Number of written symbols or negative error
1994
+ */
1995
+static ssize_t idt_sysfs_set_temp(struct device *dev,
1996
+				  struct device_attribute *da, const char *buf,
1997
+				  size_t count)
1998
+{
1999
+	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
2000
+	struct idt_ntb_dev *ndev = dev_get_drvdata(dev);
2001
+	enum idt_temp_val type = attr->index;
2002
+	long mdeg;
2003
+	int ret;
2004
+
2005
+	ret = kstrtol(buf, 10, &mdeg);
2006
+	if (ret)
2007
+		return ret;
2008
+
2009
+	/* Clamp the passed value in accordance with the type */
2010
+	if (type == IDT_TEMP_OFFSET)
2011
+		mdeg = clamp_val(mdeg, IDT_TEMP_MIN_OFFSET,
2012
+				 IDT_TEMP_MAX_OFFSET);
2013
+	else
2014
+		mdeg = clamp_val(mdeg, IDT_TEMP_MIN_MDEG, IDT_TEMP_MAX_MDEG);
2015
+
2016
+	idt_write_temp(ndev, type, mdeg);
2017
+
2018
+	return count;
2019
+}
2020
+
2021
+/*
2022
+ * idt_sysfs_reset_hist() - reset temperature history
2023
+ * @dev:	Pointer to the NTB device structure
2024
+ * @da:		Sensor device attribute structure
2025
+ * @buf:	Buffer to print temperature out
2026
+ * @count:	Size of the passed buffer
2027
+ *
2028
+ * Return: Number of written symbols or negative error
2029
+ */
2030
+static ssize_t idt_sysfs_reset_hist(struct device *dev,
2031
+				    struct device_attribute *da,
2032
+				    const char *buf, size_t count)
2033
+{
2034
+	struct idt_ntb_dev *ndev = dev_get_drvdata(dev);
2035
+
2036
+	/* Just set the maximal value to the lowest temperature field and
2037
+	 * minimal value to the highest temperature field
2038
+	 */
2039
+	idt_write_temp(ndev, IDT_TEMP_LOW, IDT_TEMP_MAX_MDEG);
2040
+	idt_write_temp(ndev, IDT_TEMP_HIGH, IDT_TEMP_MIN_MDEG);
2041
+
2042
+	return count;
2043
+}
2044
+
2045
+/*
2046
+ * Hwmon IDT sysfs attributes
2047
+ */
2048
+static SENSOR_DEVICE_ATTR(temp1_input, 0444, idt_sysfs_show_temp, NULL,
2049
+			  IDT_TEMP_CUR);
2050
+static SENSOR_DEVICE_ATTR(temp1_lowest, 0444, idt_sysfs_show_temp, NULL,
2051
+			  IDT_TEMP_LOW);
2052
+static SENSOR_DEVICE_ATTR(temp1_highest, 0444, idt_sysfs_show_temp, NULL,
2053
+			  IDT_TEMP_HIGH);
2054
+static SENSOR_DEVICE_ATTR(temp1_offset, 0644, idt_sysfs_show_temp,
2055
+			  idt_sysfs_set_temp, IDT_TEMP_OFFSET);
2056
+static DEVICE_ATTR(temp1_reset_history, 0200, NULL, idt_sysfs_reset_hist);
2057
+
2058
+/*
2059
+ * Hwmon IDT sysfs attributes group
2060
+ */
2061
+static struct attribute *idt_temp_attrs[] = {
2062
+	&sensor_dev_attr_temp1_input.dev_attr.attr,
2063
+	&sensor_dev_attr_temp1_lowest.dev_attr.attr,
2064
+	&sensor_dev_attr_temp1_highest.dev_attr.attr,
2065
+	&sensor_dev_attr_temp1_offset.dev_attr.attr,
2066
+	&dev_attr_temp1_reset_history.attr,
2067
+	NULL
2068
+};
2069
+ATTRIBUTE_GROUPS(idt_temp);
2070
+
2071
+/*
2072
+ * idt_init_temp() - initialize temperature sensor interface
2073
+ * @ndev:	IDT NTB hardware driver descriptor
2074
+ *
2075
+ * Simple sensor initializarion method is responsible for device switching
2076
+ * on and resource management based hwmon interface registration. Note, that
2077
+ * since the device is shared we won't disable it on remove, but leave it
2078
+ * working until the system is powered off.
2079
+ */
2080
+static void idt_init_temp(struct idt_ntb_dev *ndev)
2081
+{
2082
+	struct device *hwmon;
2083
+
2084
+	/* Enable sensor if it hasn't been already */
2085
+	idt_sw_write(ndev, IDT_SW_TMPCTL, 0x0);
2086
+
2087
+	/* Initialize hwmon interface fields */
2088
+	mutex_init(&ndev->hwmon_mtx);
2089
+
2090
+	hwmon = devm_hwmon_device_register_with_groups(&ndev->ntb.pdev->dev,
2091
+		ndev->swcfg->name, ndev, idt_temp_groups);
2092
+	if (IS_ERR(hwmon)) {
2093
+		dev_err(&ndev->ntb.pdev->dev, "Couldn't create hwmon device");
2094
+		return;
2095
+	}
2096
+
2097
+	dev_dbg(&ndev->ntb.pdev->dev, "Temperature HWmon interface registered");
18792098 }
18802099 
18812100 /*=============================================================================
....@@ -1931,7 +2150,7 @@
19312150 		goto err_free_vectors;
19322151 	}
19332152 
1934
-	/* Unmask Message/Doorbell/SE/Temperature interrupts */
2153
+	/* Unmask Message/Doorbell/SE interrupts */
19352154 	ntint_mask = idt_nt_read(ndev, IDT_NT_NTINTMSK) & ~IDT_NTINTMSK_ALL;
19362155 	idt_nt_write(ndev, IDT_NT_NTINTMSK, ntint_mask);
19372156 
....@@ -1945,7 +2164,6 @@
19452164 
19462165 	return ret;
19472166 }
1948
-
19492167 
19502168 /*
19512169  * idt_deinit_ist() - deinitialize PCIe interrupt handler
....@@ -2004,12 +2222,6 @@
20042222 	/* Handle switch event interrupts */
20052223 	if (ntint_sts & IDT_NTINTSTS_SEVENT) {
20062224 		idt_se_isr(ndev, ntint_sts);
2007
-		handled = true;
2008
-	}
2009
-
2010
-	/* Handle temperature sensor interrupt */
2011
-	if (ntint_sts & IDT_NTINTSTS_TMPSENSOR) {
2012
-		idt_temp_isr(ndev, ntint_sts);
20132225 		handled = true;
20142226 	}
20152227 
....@@ -2123,9 +2335,9 @@
21232335 				   size_t count, loff_t *offp)
21242336 {
21252337 	struct idt_ntb_dev *ndev = filp->private_data;
2126
-	unsigned char temp, frac, idx, pidx, cnt;
2338
+	unsigned char idx, pidx, cnt;
2339
+	unsigned long irqflags, mdeg;
21272340 	ssize_t ret = 0, off = 0;
2128
-	unsigned long irqflags;
21292341 	enum ntb_speed speed;
21302342 	enum ntb_width width;
21312343 	char *strbuf;
....@@ -2274,9 +2486,10 @@
22742486 	off += scnprintf(strbuf + off, size - off, "\n");
22752487 
22762488 	/* Current temperature */
2277
-	idt_read_temp(ndev, &temp, &frac);
2489
+	idt_read_temp(ndev, IDT_TEMP_CUR, &mdeg);
22782490 	off += scnprintf(strbuf + off, size - off,
2279
-		"Switch temperature\t\t- %hhu.%hhuC\n", temp, frac);
2491
+		"Switch temperature\t\t- %hhd.%hhuC\n",
2492
+		idt_get_deg(mdeg), idt_get_deg_frac(mdeg));
22802493 
22812494 	/* Copy the buffer to the User Space */
22822495 	ret = simple_read_from_buffer(ubuf, count, offp, strbuf, off);
....@@ -2447,12 +2660,6 @@
24472660 		dev_warn(&pdev->dev,
24482661 			"Cannot set consistent DMA highmem bit mask\n");
24492662 	}
2450
-	ret = dma_coerce_mask_and_coherent(&ndev->ntb.dev,
2451
-					   dma_get_mask(&pdev->dev));
2452
-	if (ret != 0) {
2453
-		dev_err(&pdev->dev, "Failed to set NTB device DMA bit mask\n");
2454
-		return ret;
2455
-	}
24562663 
24572664 	/*
24582665 	 * Enable the device advanced error reporting. It's not critical to
....@@ -2461,8 +2668,8 @@
24612668 	ret = pci_enable_pcie_error_reporting(pdev);
24622669 	if (ret != 0)
24632670 		dev_warn(&pdev->dev, "PCIe AER capability disabled\n");
2464
-	else /* Cleanup uncorrectable error status before getting to init */
2465
-		pci_cleanup_aer_uncorrect_error_status(pdev);
2671
+	else /* Cleanup nonfatal error status before getting to init */
2672
+		pci_aer_clear_nonfatal_status(pdev);
24662673 
24672674 	/* First enable the PCI device */
24682675 	ret = pcim_enable_device(pdev);
....@@ -2570,6 +2777,9 @@
25702777 
25712778 	/* Initialize Messaging subsystem */
25722779 	idt_init_msg(ndev);
2780
+
2781
+	/* Initialize hwmon interface */
2782
+	idt_init_temp(ndev);
25732783 
25742784 	/* Initialize IDT interrupts handler */
25752785 	ret = idt_init_isr(ndev);
....@@ -2692,6 +2902,7 @@
26922902 
26932903 static int __init idt_pci_driver_init(void)
26942904 {
2905
+	int ret;
26952906 	pr_info("%s %s\n", NTB_DESC, NTB_VER);
26962907 
26972908 	/* Create the top DebugFS directory if the FS is initialized */
....@@ -2699,7 +2910,11 @@
26992910 		dbgfs_topdir = debugfs_create_dir(KBUILD_MODNAME, NULL);
27002911 
27012912 	/* Register the NTB hardware driver to handle the PCI device */
2702
-	return pci_register_driver(&idt_pci_driver);
2913
+	ret = pci_register_driver(&idt_pci_driver);
2914
+	if (ret)
2915
+		debugfs_remove_recursive(dbgfs_topdir);
2916
+
2917
+	return ret;
27032918 }
27042919 module_init(idt_pci_driver_init);
27052920