scsi: ufs: set the device reference clock setting

This patch adds configfs support to provision UFS device at runtime. This feature can be primarily useful in factory or assembly line as some devices may be required to be configured multiple times during initial system development phase. Configuration Descriptors can be written multiple times until bConfigDescrLock attribute is zero.

Configuration descriptor buffer consists of Device and Unit descriptor configurable parameters which are parsed from vendor specific provisioning file and then passed via configfs node at runtime to provision ufs device.
CONFIG_CONFIGFS_FS needs to be enabled for using this feature.

Usage:
1) To read current configuration descriptor :
cat /config/XXXX.ufshc/ufs_provision
2) To provision ufs device:
echo <config_desc_buf> > /config/XXXX.ufshc/ufs_provision

Signed-off-by Sayali Lokhande <[email protected]>

---
 Documentation/ABI/testing/configfs-driver-ufs |  18 +++
 drivers/scsi/ufs/Kconfig                      |  10 ++
 drivers/scsi/ufs/Makefile                     |   1 +
 drivers/scsi/ufs/ufs-configfs.c               | 155 ++++++++++++++++++++++++++
 drivers/scsi/ufs/ufshcd.c                     |   3 +-
 drivers/scsi/ufs/ufshcd.h                     |  17 +++
 6 files changed, 203 insertions(+), 1 deletion(-)
 create mode 100644 Documentation/ABI/testing/configfs-driver-ufs
 create mode 100644 drivers/scsi/ufs/ufs-configfs.c

Documentation/ABI/testing/configfs-driver-ufs new file +0 -0

new file mode 100644
index 0000000..eeee499c

Documentation/ABI/testing/configfs-driver-ufs new file +1 -0

+		> /config/XXXX.ufshc/ufs_provision

drivers/scsi/ufs/Kconfig +10 -0

index e27b4d4..a9a0a58 100644
@@ -100,3 +100,13 @@ config SCSI_UFS_QCOM
 
 	  Select this if you have UFS controller on QCOM chipset.
 	  If unsure, say N.
+
+config UFS_PROVISION
+	tristate "Runtime UFS Provisioning support"
+	depends on SCSI_UFSHCD && CONFIGFS_FS
+	help
+	  This enables runtime UFS provisioning support. This can be used
+	  primarily during assembly line as some devices may be required to
+	  be configured multiple times during initial development phase.
+
+	  If unsure, say N.

drivers/scsi/ufs/Makefile +1 -0

index 918f579..00110ea 100644
@@ -5,5 +5,6 @@ obj-$(CONFIG_SCSI_UFS_DWC_TC_PLATFORM) += tc-dwc-g210-pltfrm.o ufshcd-dwc.o tc-d
 obj-$(CONFIG_SCSI_UFS_QCOM) += ufs-qcom.o
 obj-$(CONFIG_SCSI_UFSHCD) += ufshcd-core.o
 ufshcd-core-objs := ufshcd.o ufs-sysfs.o
+obj-$(CONFIG_UFS_PROVISION) += ufs-configfs.o
 obj-$(CONFIG_SCSI_UFSHCD_PCI) += ufshcd-pci.o
 obj-$(CONFIG_SCSI_UFSHCD_PLATFORM) += ufshcd-pltfrm.o

drivers/scsi/ufs/ufs-configfs.c new file +12 -0

new file mode 100644
index 0000000..74563a4
@@ -0,0 +1,155 @@
+// SPDX-License-Identifier: GPL-2.0+
+// Copyright (c) 2018, Linux Foundation.
+
+#include <linux/configfs.h>
+#include <linux/err.h>
+#include <linux/string.h>
+
+#include "ufs.h"
+#include "ufshcd.h"
+
+static inline struct ufs_hba *config_item_to_hba(struct config_item *item)
+{

drivers/scsi/ufs/ufs-configfs.c new file +60 -0

+	int desc_buf_len = QUERY_DESC_CONFIGURATION_DEF_SIZE;
+	int i, ret, curr_len = 0;
+	struct ufs_hba *hba = config_item_to_hba(item);
+
+	ret = ufshcd_query_descriptor_retry(hba, UPIU_QUERY_OPCODE_READ_DESC,
+		QUERY_DESC_IDN_CONFIGURATION, 0, 0, desc_buf, &desc_buf_len);
+
+	if (ret)
+		return ret;
+
+	for (i = 0; i < desc_buf_len; i++)
+		curr_len += snprintf((buf + curr_len), (PAGE_SIZE - curr_len),
+				"0x%x ", desc_buf[i]);
+
+	return curr_len;
+}
+
+ssize_t ufshcd_desc_configfs_store(struct ufs_hba *hba,
+		const char *buf, size_t count)
+{
+	char *strbuf;
+	char *strbuf_copy;
+	u8 desc_buf[QUERY_DESC_CONFIGURATION_DEF_SIZE] = {0};
+	int desc_buf_len = QUERY_DESC_CONFIGURATION_DEF_SIZE;
+	char *token;
+	int i, ret, value;
+	u32 config_desc_lock = 0;
+
+	/* reserve one byte for null termination */
+	strbuf = kmalloc(count + 1, GFP_KERNEL);
+	if (!strbuf)
+		return -ENOMEM;
+
+	strbuf_copy = strbuf;
+	strlcpy(strbuf, buf, count + 1);
+
+	/* Just return if bConfigDescrLock is already set */
+	ret = ufshcd_query_attr(hba, UPIU_QUERY_OPCODE_READ_ATTR,
+		QUERY_ATTR_IDN_CONF_DESC_LOCK, 0, 0, &config_desc_lock);
+	if (ret)
+		goto out;
+
+	if (config_desc_lock) {
+		dev_err(hba->dev, "%s: bConfigDescrLock already set to %u, cannot re-provision device!\n",
+		__func__, config_desc_lock);
+		ret = -EINVAL;
+		goto out;
+	}
+
+	for (i = 0; i < QUERY_DESC_CONFIGURATION_DEF_SIZE; i++) {
+		token = strsep(&strbuf, " ");
+		if (!token && i)
+			break;
+
+		ret = kstrtoint(token, 0, &value);
+		if (ret) {
+			dev_err(hba->dev, "%s: kstrtoint failed %d %s\n",
+				__func__, ret, token);
+			ret = -EINVAL;
+			goto out;

drivers/scsi/ufs/ufs-configfs.c new file +40 -0

+		__func__);
+
+out:
+	kfree(strbuf_copy);
+	if (ret)
+		return ret;
+	return count;
+}
+
+static ssize_t ufs_provision_store(struct config_item *item,
+		const char *buf, size_t count)
+{
+	struct ufs_hba *hba = config_item_to_hba(item);
+
+	return ufshcd_desc_configfs_store(hba, buf, count);
+}
+
+static struct configfs_attribute ufshcd_attr_provision = {
+	.ca_name	= "ufs_provision",
+	.ca_mode	= 0644,
+	.ca_owner	= THIS_MODULE,
+	.show		= ufs_provision_show,
+	.store		= ufs_provision_store,
+};
+
+static struct configfs_attribute *ufshcd_attrs[] = {
+	&ufshcd_attr_provision,
+	NULL,
+};
+
+static struct config_item_type ufscfg_type = {
+	.ct_attrs	= ufshcd_attrs,
+	.ct_owner	= THIS_MODULE,
+};
+
+static struct configfs_subsystem ufscfg_subsys = {
+	.su_group = {
+		.cg_item = {
+			.ci_type = &ufscfg_type,
+		},

drivers/scsi/ufs/ufs-configfs.c new file +13 -0

+	config_group_init(&subsys->su_group);
+	mutex_init(&subsys->su_mutex);
+	ret = configfs_register_subsystem(subsys);
+	if (ret)
+		pr_err("Error %d while registering subsystem %s\n",
+		       ret,
+		       subsys->su_group.cg_item.ci_namebuf);
+}
+
+void ufshcd_configfs_exit(void)
+{
+	configfs_unregister_subsystem(&ufscfg_subsys);
+}

drivers/scsi/ufs/ufshcd.c +2 -1

index e01cdc0..32a67b0 100644
@@ -7711,6 +7711,7 @@ int ufshcd_shutdown(struct ufs_hba *hba)
 void ufshcd_remove(struct ufs_hba *hba)
 {
 	ufs_sysfs_remove_nodes(hba->dev);
+	ufshcd_configfs_exit();
 	scsi_remove_host(hba->host);
 	/* disable interrupts */
 	ufshcd_disable_intr(hba, hba->intr_mask);

@@ -7965,7 +7966,7 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq)
 
 	async_schedule(ufshcd_async_scan, hba);
 	ufs_sysfs_add_nodes(hba->dev);
-
+	ufshcd_configfs_init(hba, dev_name(hba->dev));
 	return 0;
 
 out_remove_scsi_host:

drivers/scsi/ufs/ufshcd.h +17 -0

index 45013b6..2275032 100644
@@ -37,6 +37,7 @@
 #ifndef _UFSHCD_H
 #define _UFSHCD_H
 
+#include <linux/configfs.h>
 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/init.h>

@@ -515,6 +516,9 @@ struct ufs_hba {
 
 	struct Scsi_Host *host;
 	struct device *dev;
+#ifdef CONFIG_UFS_PROVISION
+	struct configfs_subsystem subsys;
+#endif
 	/*
 	 * This field is to keep a reference to "scsi_device" corresponding to
 	 * "UFS device" W-LU.

@@ -868,6 +872,19 @@ int ufshcd_read_string_desc(struct ufs_hba *hba, int desc_index,
 int ufshcd_hold(struct ufs_hba *hba, bool async);
 void ufshcd_release(struct ufs_hba *hba);
 
+/* Expose UFS configfs API's */
+#ifndef CONFIG_UFS_PROVISION
+static inline void ufshcd_configfs_init(struct ufs_hba *hba, const char *name)
+{
+}
+static inline void ufshcd_configfs_exit(void)
+{
+}
+#else
+void ufshcd_configfs_init(struct ufs_hba *hba, const char *name);
+void ufshcd_configfs_exit(void);
+#endif
+
 int ufshcd_map_desc_id_to_length(struct ufs_hba *hba, enum desc_idn desc_id,
 	int *desc_length);
 

Quoted 37 lines · Sayali Lokhande

This patch adds configfs support to provision UFS device at runtime. This feature can be primarily useful in factory or assembly line as some devices may be required to be configured multiple times during initial system development phase. Configuration Descriptors can be written multiple times until bConfigDescrLock attribute is zero.

Configuration descriptor buffer consists of Device and Unit descriptor configurable parameters which are parsed from vendor specific provisioning file and then passed via configfs node at runtime to provision ufs device.
CONFIG_CONFIGFS_FS needs to be enabled for using this feature.

Usage:
1) To read current configuration descriptor :
cat /config/XXXX.ufshc/ufs_provision
2) To provision ufs device:
echo <config_desc_buf> > /config/XXXX.ufshc/ufs_provision

Signed-off-by Sayali Lokhande <[email protected]>

---
  Documentation/ABI/testing/configfs-driver-ufs |  18 +++
  drivers/scsi/ufs/Kconfig                      |  10 ++
  drivers/scsi/ufs/Makefile                     |   1 +
  drivers/scsi/ufs/ufs-configfs.c               | 155 ++++++++++++++++++++++++++
  drivers/scsi/ufs/ufshcd.c                     |   3 +-
  drivers/scsi/ufs/ufshcd.h                     |  17 +++
  6 files changed, 203 insertions(+), 1 deletion(-)

create mode 100644 Documentation/ABI/testing/configfs-driver-ufs create mode 100644 drivers/scsi/ufs/ufs-configfs.c

Documentation/ABI/testing/configfs-driver-ufs new file +0 -0

new file mode 100644
index 0000000..eeee499c

Documentation/ABI/testing/configfs-driver-ufs line 1

Quoted 1 line

Documentation/ABI/testing/configfs-driver-ufs new file +1 -0

@@ -0,0 +1,18 @@
+What:		/config/ufshcd/ufs_provision

You are using the device name as the config subsystem name, so this is really:

	What:		/config/*/ufs_provision

Documentation/ABI/testing/configfs-driver-ufs line 3

Quoted 2 lines

Documentation/ABI/testing/configfs-driver-ufs new file +2 -0

+Date:		Jun 2018
+KernelVersion:	4.14

4.19 maybe

Documentation/ABI/testing/configfs-driver-ufs line 5

Quoted 2 lines

Documentation/ABI/testing/configfs-driver-ufs new file +2 -0

+Description:
+		This file shows the current ufs configuration descriptor set in device.

It is only the first config descriptor though isn't it? There is no support for the other 3. Shouldn't we support config descriptors fully?

Documentation/ABI/testing/configfs-driver-ufs line 11

Quoted 6 lines

Documentation/ABI/testing/configfs-driver-ufs new file +6 -0

+		This can be used to provision ufs device if bConfigDescrLock is 0.
+		For more details, refer 14.1.6.3 Configuration Descriptor and
+		Table 14-12 - Unit Descriptor configurable parameters from specs for
+		description of each configuration descriptor parameter.
+		Configuration descriptor buffer needs to be passed in space separated
+		format specificied as below:

specificied -> specified

Documentation/ABI/testing/configfs-driver-ufs line 17

Quoted 6 lines

Documentation/ABI/testing/configfs-driver-ufs new file +6 -0

+		echo <bLength> <bDescriptorIDN> <bConfDescContinue> <bBootEnable>
+		<bDescrAccessEn> <bInitPowerMode> <bHighPriorityLUN>
+		<bSecureRemovalType> <bInitActiveICCLevel> <wPeriodicRTCUpdate>
+		<0Bh:0Fh_ReservedAs_0> <bLUEnable> <bBootLunID> <bLUWriteProtect>
+		<bMemoryType> <dNumAllocUnits> <bDataReliability> <bLogicalBlockSize>
+		<bProvisioningType> <wContextCapabilities> <0Dh:0Fh_ReservedAs_0>

This format is not exactly correct anymore because each byte has to be represented separately. Also theoretically it can be change, so maybe better just to refer the user to the UFS specification.

Quoted 51 lines

Documentation/ABI/testing/configfs-driver-ufs new file +1 -0

+		> /config/XXXX.ufshc/ufs_provision

drivers/scsi/ufs/Kconfig +10 -0

index e27b4d4..a9a0a58 100644
@@ -100,3 +100,13 @@ config SCSI_UFS_QCOM
 
  	  Select this if you have UFS controller on QCOM chipset.
  	  If unsure, say N.
+
+config UFS_PROVISION
+	tristate "Runtime UFS Provisioning support"
+	depends on SCSI_UFSHCD && CONFIGFS_FS
+	help
+	  This enables runtime UFS provisioning support. This can be used
+	  primarily during assembly line as some devices may be required to
+	  be configured multiple times during initial development phase.
+
+	  If unsure, say N.

drivers/scsi/ufs/Makefile +1 -0

index 918f579..00110ea 100644
@@ -5,5 +5,6 @@ obj-$(CONFIG_SCSI_UFS_DWC_TC_PLATFORM) += tc-dwc-g210-pltfrm.o ufshcd-dwc.o tc-d
  obj-$(CONFIG_SCSI_UFS_QCOM) += ufs-qcom.o
  obj-$(CONFIG_SCSI_UFSHCD) += ufshcd-core.o
  ufshcd-core-objs := ufshcd.o ufs-sysfs.o
+obj-$(CONFIG_UFS_PROVISION) += ufs-configfs.o
  obj-$(CONFIG_SCSI_UFSHCD_PCI) += ufshcd-pci.o
  obj-$(CONFIG_SCSI_UFSHCD_PLATFORM) += ufshcd-pltfrm.o

drivers/scsi/ufs/ufs-configfs.c new file +15 -0

new file mode 100644
index 0000000..74563a4
@@ -0,0 +1,155 @@
+// SPDX-License-Identifier: GPL-2.0+
+// Copyright (c) 2018, Linux Foundation.
+
+#include <linux/configfs.h>
+#include <linux/err.h>
+#include <linux/string.h>
+
+#include "ufs.h"
+#include "ufshcd.h"
+
+static inline struct ufs_hba *config_item_to_hba(struct config_item *item)
+{
+	struct config_group *group = to_config_group(item);
+	struct configfs_subsystem *subsys = to_configfs_subsystem(group);
+	struct ufs_hba *hba = container_of(subsys, struct ufs_hba, subsys);

drivers/scsi/ufs/ufs-configfs.c line 22

Quoted 7 lines

drivers/scsi/ufs/ufs-configfs.c new file +7 -0

+
+	return subsys ? hba : NULL;
+}
+
+static ssize_t ufs_provision_show(struct config_item *item, char *buf)
+{
+	u8 desc_buf[QUERY_DESC_CONFIGURATION_DEF_SIZE] = {0};

Is it really ok to hard-code the descriptor size?

Quoted 65 lines

drivers/scsi/ufs/ufs-configfs.c new file +65 -0

+	int desc_buf_len = QUERY_DESC_CONFIGURATION_DEF_SIZE;
+	int i, ret, curr_len = 0;
+	struct ufs_hba *hba = config_item_to_hba(item);
+
+	ret = ufshcd_query_descriptor_retry(hba, UPIU_QUERY_OPCODE_READ_DESC,
+		QUERY_DESC_IDN_CONFIGURATION, 0, 0, desc_buf, &desc_buf_len);
+
+	if (ret)
+		return ret;
+
+	for (i = 0; i < desc_buf_len; i++)
+		curr_len += snprintf((buf + curr_len), (PAGE_SIZE - curr_len),
+				"0x%x ", desc_buf[i]);
+
+	return curr_len;
+}
+
+ssize_t ufshcd_desc_configfs_store(struct ufs_hba *hba,
+		const char *buf, size_t count)
+{
+	char *strbuf;
+	char *strbuf_copy;
+	u8 desc_buf[QUERY_DESC_CONFIGURATION_DEF_SIZE] = {0};
+	int desc_buf_len = QUERY_DESC_CONFIGURATION_DEF_SIZE;
+	char *token;
+	int i, ret, value;
+	u32 config_desc_lock = 0;
+
+	/* reserve one byte for null termination */
+	strbuf = kmalloc(count + 1, GFP_KERNEL);
+	if (!strbuf)
+		return -ENOMEM;
+
+	strbuf_copy = strbuf;
+	strlcpy(strbuf, buf, count + 1);
+
+	/* Just return if bConfigDescrLock is already set */
+	ret = ufshcd_query_attr(hba, UPIU_QUERY_OPCODE_READ_ATTR,
+		QUERY_ATTR_IDN_CONF_DESC_LOCK, 0, 0, &config_desc_lock);
+	if (ret)
+		goto out;
+
+	if (config_desc_lock) {
+		dev_err(hba->dev, "%s: bConfigDescrLock already set to %u, cannot re-provision device!\n",
+		__func__, config_desc_lock);
+		ret = -EINVAL;
+		goto out;
+	}
+
+	for (i = 0; i < QUERY_DESC_CONFIGURATION_DEF_SIZE; i++) {
+		token = strsep(&strbuf, " ");
+		if (!token && i)
+			break;
+
+		ret = kstrtoint(token, 0, &value);
+		if (ret) {
+			dev_err(hba->dev, "%s: kstrtoint failed %d %s\n",
+				__func__, ret, token);
+			ret = -EINVAL;
+			goto out;
+		}
+		desc_buf[i] = (u8)value;
+	}
+
+	/* Write configuration descriptor to provision ufs */

drivers/scsi/ufs/ufs-configfs.c line 92

Quoted 5 lines

drivers/scsi/ufs/ufs-configfs.c new file +5 -0

+	ret = ufshcd_query_descriptor_retry(hba, UPIU_QUERY_OPCODE_WRITE_DESC,
+		QUERY_DESC_IDN_CONFIGURATION, 0, 0, desc_buf, &desc_buf_len);
+
+	if (!ret)
+		dev_info(hba->dev, "%s: UFS Provisioning done, reboot now!\n",

That is not necessarily true - bConfDescContinue might have been used or bConfigDescrLock might need to be set. Better just to say that configuration descriptor 0 was written.

Quoted 45 lines

drivers/scsi/ufs/ufs-configfs.c new file +44 -0

+		__func__);
+
+out:
+	kfree(strbuf_copy);
+	if (ret)
+		return ret;
+	return count;
+}
+
+static ssize_t ufs_provision_store(struct config_item *item,
+		const char *buf, size_t count)
+{
+	struct ufs_hba *hba = config_item_to_hba(item);
+
+	return ufshcd_desc_configfs_store(hba, buf, count);
+}
+
+static struct configfs_attribute ufshcd_attr_provision = {
+	.ca_name	= "ufs_provision",
+	.ca_mode	= 0644,
+	.ca_owner	= THIS_MODULE,
+	.show		= ufs_provision_show,
+	.store		= ufs_provision_store,
+};
+
+static struct configfs_attribute *ufshcd_attrs[] = {
+	&ufshcd_attr_provision,
+	NULL,
+};
+
+static struct config_item_type ufscfg_type = {
+	.ct_attrs	= ufshcd_attrs,
+	.ct_owner	= THIS_MODULE,
+};
+
+static struct configfs_subsystem ufscfg_subsys = {
+	.su_group = {
+		.cg_item = {
+			.ci_type = &ufscfg_type,
+		},
+	},
+};
+
+void ufshcd_configfs_init(struct ufs_hba *hba, const char *name)

drivers/scsi/ufs/ufs-configfs.c line 142

Quoted 6 lines

drivers/scsi/ufs/ufs-configfs.c new file +6 -0

+{
+	int ret;
+	struct configfs_subsystem *subsys = &hba->subsys;
+
+	strncpy(ufscfg_subsys.su_group.cg_item.ci_namebuf, name, strlen(name));
+	subsys->su_group = ufscfg_subsys.su_group;

configfs_subsystem cannot share su_group with other configfs_subsystem i.e you are not allowing for there being more than 1 hba

Quoted 77 lines

drivers/scsi/ufs/ufs-configfs.c new file +13 -0

+	config_group_init(&subsys->su_group);
+	mutex_init(&subsys->su_mutex);
+	ret = configfs_register_subsystem(subsys);
+	if (ret)
+		pr_err("Error %d while registering subsystem %s\n",
+		       ret,
+		       subsys->su_group.cg_item.ci_namebuf);
+}
+
+void ufshcd_configfs_exit(void)
+{
+	configfs_unregister_subsystem(&ufscfg_subsys);
+}

drivers/scsi/ufs/ufshcd.c +2 -1

index e01cdc0..32a67b0 100644
@@ -7711,6 +7711,7 @@ int ufshcd_shutdown(struct ufs_hba *hba)
  void ufshcd_remove(struct ufs_hba *hba)
  {
  	ufs_sysfs_remove_nodes(hba->dev);
+	ufshcd_configfs_exit();
  	scsi_remove_host(hba->host);
  	/* disable interrupts */
  	ufshcd_disable_intr(hba, hba->intr_mask);

@@ -7965,7 +7966,7 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq)
 
  	async_schedule(ufshcd_async_scan, hba);
  	ufs_sysfs_add_nodes(hba->dev);
-
+	ufshcd_configfs_init(hba, dev_name(hba->dev));
  	return 0;
 
  out_remove_scsi_host:

drivers/scsi/ufs/ufshcd.h +17 -0

index 45013b6..2275032 100644
@@ -37,6 +37,7 @@
  #ifndef _UFSHCD_H
  #define _UFSHCD_H
 
+#include <linux/configfs.h>
  #include <linux/module.h>
  #include <linux/kernel.h>
  #include <linux/init.h>

@@ -515,6 +516,9 @@ struct ufs_hba {
 
  	struct Scsi_Host *host;
  	struct device *dev;
+#ifdef CONFIG_UFS_PROVISION
+	struct configfs_subsystem subsys;
+#endif
  	/*
  	 * This field is to keep a reference to "scsi_device" corresponding to
  	 * "UFS device" W-LU.

@@ -868,6 +872,19 @@ int ufshcd_read_string_desc(struct ufs_hba *hba, int desc_index,
  int ufshcd_hold(struct ufs_hba *hba, bool async);
  void ufshcd_release(struct ufs_hba *hba);
 
+/* Expose UFS configfs API's */
+#ifndef CONFIG_UFS_PROVISION
+static inline void ufshcd_configfs_init(struct ufs_hba *hba, const char *name)
+{
+}
+static inline void ufshcd_configfs_exit(void)
+{
+}
+#else
+void ufshcd_configfs_init(struct ufs_hba *hba, const char *name);
+void ufshcd_configfs_exit(void);
+#endif
+
  int ufshcd_map_desc_id_to_length(struct ufs_hba *hba, enum desc_idn desc_id,
  	int *desc_length);
 

Hi Adrian,

Quoted 44 lines · Sayali Lokhande

Quoted 39 lines

This patch adds configfs support to provision UFS device at runtime. This feature can be primarily useful in factory or assembly line as some devices may be required to be configured multiple times during initial system development phase. Configuration Descriptors can be written multiple times until bConfigDescrLock attribute is zero.

Configuration descriptor buffer consists of Device and Unit descriptor configurable parameters which are parsed from vendor specific provisioning file and then passed via configfs node at runtime to provision ufs device.
CONFIG_CONFIGFS_FS needs to be enabled for using this feature.

Usage:
1) To read current configuration descriptor :
    cat /config/XXXX.ufshc/ufs_provision
2) To provision ufs device:
    echo <config_desc_buf> > /config/XXXX.ufshc/ufs_provision

Signed-off-by Sayali Lokhande <[email protected]>

---
  Documentation/ABI/testing/configfs-driver-ufs |  18 +++ drivers/scsi/ufs/Kconfig                      |  10 ++ drivers/scsi/ufs/Makefile                     |   1 + drivers/scsi/ufs/ufs-configfs.c               | 155
++++++++++++++++++++++++++
  drivers/scsi/ufs/ufshcd.c                     |   3 +- drivers/scsi/ufs/ufshcd.h                     |  17 +++

  6 files changed, 203 insertions(+), 1 deletion(-)

  create mode 100644 Documentation/ABI/testing/configfs-driver-ufs create mode 100644 drivers/scsi/ufs/ufs-configfs.c

Documentation/ABI/testing/configfs-driver-ufs new file +0 -0

new file mode 100644
index 0000000..eeee499c

Documentation/ABI/testing/configfs-driver-ufs line 1

Quoted 1 line

Documentation/ABI/testing/configfs-driver-ufs new file +1 -0

@@ -0,0 +1,18 @@
+What:        /config/ufshcd/ufs_provision

You are using the device name as the config subsystem name, so this is really:

Quoted 1 line

    What:        /config/*/ufs_provision

Agree. Will update.

Quoted 3 lines

Documentation/ABI/testing/configfs-driver-ufs line 3

Quoted 2 lines

Documentation/ABI/testing/configfs-driver-ufs new file +2 -0

+Date:        Jun 2018
+KernelVersion:    4.14

4.19 maybe

Done.

Quoted 5 lines

Quoted 3 lines

Documentation/ABI/testing/configfs-driver-ufs new file +2 -0

+Description:
+        This file shows the current ufs configuration descriptor set in

device.

It is only the first config descriptor though isn't it?  There is no support for the other 3.  Shouldn't we support config descriptors fully?

Yes, we should support config descriptors fully. My current implementation only supports config desc (index = 00h).
I m thinking I can add separate "index" field along with "ufs_provision" field and can use this index (instead of hard coding to 0)
to write repective config_desc. In this way, we should first set the "index" and then read/write to "ufs_provision".
Let me know if you have any concern with this approach ?

Quoted 9 lines

Quoted 8 lines

+        This can be used to provision ufs device if bConfigDescrLock is 0. +        For more details, refer 14.1.6.3 Configuration Descriptor and +        Table 14-12 - Unit Descriptor configurable parameters from specs for
+        description of each configuration descriptor parameter. +        Configuration descriptor buffer needs to be passed in space separated
+        format specificied as below:

specificied -> specified

Done

Quoted 10 lines

Quoted 7 lines

+        echo <bLength> <bDescriptorIDN> <bConfDescContinue> <bBootEnable> +        <bDescrAccessEn> <bInitPowerMode> <bHighPriorityLUN> +        <bSecureRemovalType> <bInitActiveICCLevel> <wPeriodicRTCUpdate> +        <0Bh:0Fh_ReservedAs_0> <bLUEnable> <bBootLunID> <bLUWriteProtect> +        <bMemoryType> <dNumAllocUnits> <bDataReliability> <bLogicalBlockSize>
+        <bProvisioningType> <wContextCapabilities> <0Dh:0Fh_ReservedAs_0>

This format is not exactly correct anymore because each byte has to be represented separately.  Also theoretically it can be change, so maybe better just to refer the user to the UFS specification.

Agree. Will update to just refer to UFS spec (for Config_desc format).

Quoted 52 lines

Quoted 52 lines

+        > /config/XXXX.ufshc/ufs_provision

drivers/scsi/ufs/Kconfig +0 -0

index e27b4d4..a9a0a58 100644
@@ -100,3 +100,13 @@ config SCSI_UFS_QCOM

          Select this if you have UFS controller on QCOM chipset. If unsure, say N.

drivers/scsi/ufs/Kconfig +10 -0

+
+config UFS_PROVISION
+    tristate "Runtime UFS Provisioning support"
+    depends on SCSI_UFSHCD && CONFIGFS_FS
+    help
+      This enables runtime UFS provisioning support. This can be used
+      primarily during assembly line as some devices may be required to
+      be configured multiple times during initial development phase.
+
+      If unsure, say N.

drivers/scsi/ufs/Makefile +0 -0

index 918f579..00110ea 100644
@@ -5,5 +5,6 @@ obj-$(CONFIG_SCSI_UFS_DWC_TC_PLATFORM) +=

tc-dwc-g210-pltfrm.o ufshcd-dwc.o tc-d obj-$(CONFIG_SCSI_UFS_QCOM) += ufs-qcom.o obj-$(CONFIG_SCSI_UFSHCD) += ufshcd-core.o ufshcd-core-objs := ufshcd.o ufs-sysfs.o +obj-$(CONFIG_UFS_PROVISION) += ufs-configfs.o obj-$(CONFIG_SCSI_UFSHCD_PCI) += ufshcd-pci.o obj-$(CONFIG_SCSI_UFSHCD_PLATFORM) += ufshcd-pltfrm.o

drivers/scsi/ufs/ufs-configfs.c new file +15 -0

new file mode 100644
index 0000000..74563a4
@@ -0,0 +1,155 @@
+// SPDX-License-Identifier: GPL-2.0+
+// Copyright (c) 2018, Linux Foundation.
+
+#include <linux/configfs.h>
+#include <linux/err.h>
+#include <linux/string.h>
+
+#include "ufs.h"
+#include "ufshcd.h"
+
+static inline struct ufs_hba *config_item_to_hba(struct config_item *item)
+{
+    struct config_group *group = to_config_group(item);
+    struct configfs_subsystem *subsys = to_configfs_subsystem(group);
+    struct ufs_hba *hba = container_of(subsys, struct ufs_hba, subsys);

Quoted 8 lines

drivers/scsi/ufs/ufs-configfs.c line 22

Quoted 7 lines

drivers/scsi/ufs/ufs-configfs.c new file +7 -0

+
+    return subsys ? hba : NULL;
+}
+
+static ssize_t ufs_provision_show(struct config_item *item, char *buf)
+{
+    u8 desc_buf[QUERY_DESC_CONFIGURATION_DEF_SIZE] = {0};

Is it really ok to hard-code the descriptor size?

I will use ufshcd_read_desc_length() api for each index as required. Will remove this hard-code.

Quoted 66 lines

Quoted 66 lines

drivers/scsi/ufs/ufs-configfs.c new file +44 -0

+    int desc_buf_len = QUERY_DESC_CONFIGURATION_DEF_SIZE;
+    int i, ret, curr_len = 0;
+    struct ufs_hba *hba = config_item_to_hba(item);
+
+    ret = ufshcd_query_descriptor_retry(hba, UPIU_QUERY_OPCODE_READ_DESC,
+        QUERY_DESC_IDN_CONFIGURATION, 0, 0, desc_buf, &desc_buf_len);
+
+    if (ret)
+        return ret;
+
+    for (i = 0; i < desc_buf_len; i++)
+        curr_len += snprintf((buf + curr_len), (PAGE_SIZE - curr_len),
+                "0x%x ", desc_buf[i]);
+
+    return curr_len;
+}
+
+ssize_t ufshcd_desc_configfs_store(struct ufs_hba *hba,
+        const char *buf, size_t count)
+{
+    char *strbuf;
+    char *strbuf_copy;
+    u8 desc_buf[QUERY_DESC_CONFIGURATION_DEF_SIZE] = {0};
+    int desc_buf_len = QUERY_DESC_CONFIGURATION_DEF_SIZE;
+    char *token;
+    int i, ret, value;
+    u32 config_desc_lock = 0;
+
+    /* reserve one byte for null termination */
+    strbuf = kmalloc(count + 1, GFP_KERNEL);
+    if (!strbuf)
+        return -ENOMEM;
+
+    strbuf_copy = strbuf;
+    strlcpy(strbuf, buf, count + 1);
+
+    /* Just return if bConfigDescrLock is already set */
+    ret = ufshcd_query_attr(hba, UPIU_QUERY_OPCODE_READ_ATTR,
+        QUERY_ATTR_IDN_CONF_DESC_LOCK, 0, 0, &config_desc_lock);
+    if (ret)
+        goto out;
+
+    if (config_desc_lock) {
+        dev_err(hba->dev, "%s: bConfigDescrLock already set to %u,

cannot re-provision device!\n",
+        __func__, config_desc_lock);
+        ret = -EINVAL;
+        goto out;
+    }

drivers/scsi/ufs/ufs-configfs.c new file +17 -0

+
+    for (i = 0; i < QUERY_DESC_CONFIGURATION_DEF_SIZE; i++) {
+        token = strsep(&strbuf, " ");
+        if (!token && i)
+            break;
+
+        ret = kstrtoint(token, 0, &value);
+        if (ret) {
+            dev_err(hba->dev, "%s: kstrtoint failed %d %s\n",
+                __func__, ret, token);
+            ret = -EINVAL;
+            goto out;
+        }
+        desc_buf[i] = (u8)value;
+    }
+
+    /* Write configuration descriptor to provision ufs */

Quoted 8 lines

Quoted 5 lines

+    ret = ufshcd_query_descriptor_retry(hba, UPIU_QUERY_OPCODE_WRITE_DESC, +        QUERY_DESC_IDN_CONFIGURATION, 0, 0, desc_buf, &desc_buf_len); +
+    if (!ret)
+        dev_info(hba->dev, "%s: UFS Provisioning done, reboot now!\n",

That is not necessarily true - bConfDescContinue might have been used or bConfigDescrLock might need to be set.  Better just to say that configuration descriptor 0 was written.

Agree. Will update.

Quoted 45 lines

Quoted 45 lines

+        __func__);

drivers/scsi/ufs/ufs-configfs.c new file +43 -0

+
+out:
+    kfree(strbuf_copy);
+    if (ret)
+        return ret;
+    return count;
+}
+
+static ssize_t ufs_provision_store(struct config_item *item,
+        const char *buf, size_t count)
+{
+    struct ufs_hba *hba = config_item_to_hba(item);
+
+    return ufshcd_desc_configfs_store(hba, buf, count);
+}
+
+static struct configfs_attribute ufshcd_attr_provision = {
+    .ca_name    = "ufs_provision",
+    .ca_mode    = 0644,
+    .ca_owner    = THIS_MODULE,
+    .show        = ufs_provision_show,
+    .store        = ufs_provision_store,
+};
+
+static struct configfs_attribute *ufshcd_attrs[] = {
+    &ufshcd_attr_provision,
+    NULL,
+};
+
+static struct config_item_type ufscfg_type = {
+    .ct_attrs    = ufshcd_attrs,
+    .ct_owner    = THIS_MODULE,
+};
+
+static struct configfs_subsystem ufscfg_subsys = {
+    .su_group = {
+        .cg_item = {
+            .ci_type = &ufscfg_type,
+        },
+    },
+};
+
+void ufshcd_configfs_init(struct ufs_hba *hba, const char *name)

Quoted 8 lines

drivers/scsi/ufs/ufs-configfs.c line 142

Quoted 6 lines

drivers/scsi/ufs/ufs-configfs.c new file +6 -0

+{
+    int ret;
+    struct configfs_subsystem *subsys = &hba->subsys;
+
+    strncpy(ufscfg_subsys.su_group.cg_item.ci_namebuf, name, strlen(name));
+    subsys->su_group = ufscfg_subsys.su_group;

configfs_subsystem cannot share su_group with other configfs_subsystem i.e you are not allowing for there being more than 1 hba

Agree. I think I will have to move above declarations(ufscfg_subsys/ufscfg_type/ufshcd_attrs) in driver .c/.h file (to make it per ufs hba/probe).
Will check and update.

Quoted 75 lines

Quoted 75 lines

+    config_group_init(&subsys->su_group);
+    mutex_init(&subsys->su_mutex);
+    ret = configfs_register_subsystem(subsys);
+    if (ret)
+        pr_err("Error %d while registering subsystem %s\n", +               ret,
+               subsys->su_group.cg_item.ci_namebuf);

drivers/scsi/ufs/ufs-configfs.c new file +6 -0

+}
+
+void ufshcd_configfs_exit(void)
+{
+    configfs_unregister_subsystem(&ufscfg_subsys);
+}

drivers/scsi/ufs/ufshcd.c +2 -1

index e01cdc0..32a67b0 100644
@@ -7711,6 +7711,7 @@ int ufshcd_shutdown(struct ufs_hba *hba)
   void ufshcd_remove(struct ufs_hba *hba)
   {
       ufs_sysfs_remove_nodes(hba->dev);
+    ufshcd_configfs_exit();
       scsi_remove_host(hba->host);
       /* disable interrupts */
       ufshcd_disable_intr(hba, hba->intr_mask);

@@ -7965,7 +7966,7 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem
 *mmio_base, unsigned int irq)
         async_schedule(ufshcd_async_scan, hba);
       ufs_sysfs_add_nodes(hba->dev);
-
+    ufshcd_configfs_init(hba, dev_name(hba->dev));
       return 0;

    out_remove_scsi_host:

drivers/scsi/ufs/ufshcd.h +0 -0

index 45013b6..2275032 100644
@@ -37,6 +37,7 @@
   #ifndef _UFSHCD_H
   #define _UFSHCD_H

  +#include <linux/configfs.h>
  #include <linux/module.h>
  #include <linux/kernel.h>
  #include <linux/init.h>

drivers/scsi/ufs/ufshcd.h +3 -0

@@ -515,6 +516,9 @@ struct ufs_hba {
         struct Scsi_Host *host;
       struct device *dev;
+#ifdef CONFIG_UFS_PROVISION
+    struct configfs_subsystem subsys;
+#endif
       /*
        * This field is to keep a reference to "scsi_device" corresponding to
        * "UFS device" W-LU.

@@ -868,6 +872,19 @@ int ufshcd_read_string_desc(struct ufs_hba *hba, int
 desc_index,
   int ufshcd_hold(struct ufs_hba *hba, bool async);
   void ufshcd_release(struct ufs_hba *hba);

  +/* Expose UFS configfs API's */

drivers/scsi/ufs/ufshcd.h +2 -0

+#ifndef CONFIG_UFS_PROVISION
+static inline void ufshcd_configfs_init(struct ufs_hba *hba, const char

*name)

drivers/scsi/ufs/ufshcd.h +10 -0

+{
+}
+static inline void ufshcd_configfs_exit(void)
+{
+}
+#else
+void ufshcd_configfs_init(struct ufs_hba *hba, const char *name);
+void ufshcd_configfs_exit(void);
+#endif
+

  int ufshcd_map_desc_id_to_length(struct ufs_hba *hba, enum desc_idn desc_id,
      int *desc_length);

Hi Adrian,

Quoted 44 lines · Adrian Hunter

Quoted 39 lines · Sayali Lokhande

This patch adds configfs support to provision UFS device at runtime. This feature can be primarily useful in factory or assembly line as some devices may be required to be configured multiple times during initial system development phase. Configuration Descriptors can be written multiple times until bConfigDescrLock attribute is zero.

Configuration descriptor buffer consists of Device and Unit descriptor configurable parameters which are parsed from vendor specific provisioning file and then passed via configfs node at runtime to provision ufs device.
CONFIG_CONFIGFS_FS needs to be enabled for using this feature.

Usage:
1) To read current configuration descriptor :
    cat /config/XXXX.ufshc/ufs_provision
2) To provision ufs device:
    echo <config_desc_buf> > /config/XXXX.ufshc/ufs_provision

Signed-off-by Sayali Lokhande <[email protected]>

---
  Documentation/ABI/testing/configfs-driver-ufs |  18 +++ drivers/scsi/ufs/Kconfig                      |  10 ++ drivers/scsi/ufs/Makefile                     |   1 + drivers/scsi/ufs/ufs-configfs.c               | 155
++++++++++++++++++++++++++
  drivers/scsi/ufs/ufshcd.c                     |   3 +- drivers/scsi/ufs/ufshcd.h                     |  17 +++

  6 files changed, 203 insertions(+), 1 deletion(-)

  create mode 100644 Documentation/ABI/testing/configfs-driver-ufs create mode 100644 drivers/scsi/ufs/ufs-configfs.c

Documentation/ABI/testing/configfs-driver-ufs new file +0 -0

new file mode 100644
index 0000000..eeee499c

Documentation/ABI/testing/configfs-driver-ufs line 1

Quoted 1 line

Documentation/ABI/testing/configfs-driver-ufs new file +1 -0

@@ -0,0 +1,18 @@
+What:        /config/ufshcd/ufs_provision

You are using the device name as the config subsystem name, so this is really:

Quoted 1 line

    What:        /config/*/ufs_provision

Agree. Will update.

Quoted 3 lines

Documentation/ABI/testing/configfs-driver-ufs line 3

Quoted 2 lines

Documentation/ABI/testing/configfs-driver-ufs new file +2 -0

+Date:        Jun 2018
+KernelVersion:    4.14

4.19 maybe

Done.

Quoted 5 lines

Quoted 3 lines

Documentation/ABI/testing/configfs-driver-ufs new file +2 -0

+Description:
+        This file shows the current ufs configuration descriptor set in

device.

It is only the first config descriptor though isn't it?  There is no support for the other 3.  Shouldn't we support config descriptors fully?

Yes, we should support config descriptors fully. My current implementation only supports config desc (index = 00h).
I m thinking I can add separate "index" field along with "ufs_provision" field and can use this index (instead of hard coding to 0)
to write repective config_desc. In this way, we should first set the "index" and then read/write to "ufs_provision".
Let me know if you have any concern with this approach ?

Quoted 10 lines

Quoted 9 lines

+        This can be used to provision ufs device if bConfigDescrLock is 0. +        For more details, refer 14.1.6.3 Configuration Descriptor and +        Table 14-12 - Unit Descriptor configurable parameters from specs for
+        description of each configuration descriptor parameter. +        Configuration descriptor buffer needs to be passed in space separated
+        format specificied as below:

specificied -> specified

Done

Quoted 10 lines

Quoted 7 lines

+        echo <bLength> <bDescriptorIDN> <bConfDescContinue> <bBootEnable> +        <bDescrAccessEn> <bInitPowerMode> <bHighPriorityLUN> +        <bSecureRemovalType> <bInitActiveICCLevel> <wPeriodicRTCUpdate> +        <0Bh:0Fh_ReservedAs_0> <bLUEnable> <bBootLunID> <bLUWriteProtect> +        <bMemoryType> <dNumAllocUnits> <bDataReliability> <bLogicalBlockSize>
+        <bProvisioningType> <wContextCapabilities> <0Dh:0Fh_ReservedAs_0>

This format is not exactly correct anymore because each byte has to be represented separately.  Also theoretically it can be change, so maybe better just to refer the user to the UFS specification.

Agree. Will update to just refer to UFS spec (for Config_desc format).

Quoted 52 lines

Quoted 52 lines

+        > /config/XXXX.ufshc/ufs_provision

drivers/scsi/ufs/Kconfig +0 -0

index e27b4d4..a9a0a58 100644
@@ -100,3 +100,13 @@ config SCSI_UFS_QCOM

          Select this if you have UFS controller on QCOM chipset. If unsure, say N.

drivers/scsi/ufs/Kconfig +10 -0

+
+config UFS_PROVISION
+    tristate "Runtime UFS Provisioning support"
+    depends on SCSI_UFSHCD && CONFIGFS_FS
+    help
+      This enables runtime UFS provisioning support. This can be used
+      primarily during assembly line as some devices may be required to
+      be configured multiple times during initial development phase.
+
+      If unsure, say N.

drivers/scsi/ufs/Makefile +0 -0

index 918f579..00110ea 100644
@@ -5,5 +5,6 @@ obj-$(CONFIG_SCSI_UFS_DWC_TC_PLATFORM) +=

tc-dwc-g210-pltfrm.o ufshcd-dwc.o tc-d obj-$(CONFIG_SCSI_UFS_QCOM) += ufs-qcom.o obj-$(CONFIG_SCSI_UFSHCD) += ufshcd-core.o ufshcd-core-objs := ufshcd.o ufs-sysfs.o +obj-$(CONFIG_UFS_PROVISION) += ufs-configfs.o obj-$(CONFIG_SCSI_UFSHCD_PCI) += ufshcd-pci.o obj-$(CONFIG_SCSI_UFSHCD_PLATFORM) += ufshcd-pltfrm.o

drivers/scsi/ufs/ufs-configfs.c new file +15 -0

new file mode 100644
index 0000000..74563a4
@@ -0,0 +1,155 @@
+// SPDX-License-Identifier: GPL-2.0+
+// Copyright (c) 2018, Linux Foundation.
+
+#include <linux/configfs.h>
+#include <linux/err.h>
+#include <linux/string.h>
+
+#include "ufs.h"
+#include "ufshcd.h"
+
+static inline struct ufs_hba *config_item_to_hba(struct config_item *item)
+{
+    struct config_group *group = to_config_group(item);
+    struct configfs_subsystem *subsys = to_configfs_subsystem(group);
+    struct ufs_hba *hba = container_of(subsys, struct ufs_hba, subsys);

Quoted 8 lines

drivers/scsi/ufs/ufs-configfs.c line 22

Quoted 7 lines

drivers/scsi/ufs/ufs-configfs.c new file +7 -0

+
+    return subsys ? hba : NULL;
+}
+
+static ssize_t ufs_provision_show(struct config_item *item, char *buf)
+{
+    u8 desc_buf[QUERY_DESC_CONFIGURATION_DEF_SIZE] = {0};

Is it really ok to hard-code the descriptor size?

I will use ufshcd_read_desc_length() api for each index as required. Will remove this hard-code.

Quoted 66 lines

Quoted 66 lines

drivers/scsi/ufs/ufs-configfs.c new file +44 -0

+    int desc_buf_len = QUERY_DESC_CONFIGURATION_DEF_SIZE;
+    int i, ret, curr_len = 0;
+    struct ufs_hba *hba = config_item_to_hba(item);
+
+    ret = ufshcd_query_descriptor_retry(hba, UPIU_QUERY_OPCODE_READ_DESC,
+        QUERY_DESC_IDN_CONFIGURATION, 0, 0, desc_buf, &desc_buf_len);
+
+    if (ret)
+        return ret;
+
+    for (i = 0; i < desc_buf_len; i++)
+        curr_len += snprintf((buf + curr_len), (PAGE_SIZE - curr_len),
+                "0x%x ", desc_buf[i]);
+
+    return curr_len;
+}
+
+ssize_t ufshcd_desc_configfs_store(struct ufs_hba *hba,
+        const char *buf, size_t count)
+{
+    char *strbuf;
+    char *strbuf_copy;
+    u8 desc_buf[QUERY_DESC_CONFIGURATION_DEF_SIZE] = {0};
+    int desc_buf_len = QUERY_DESC_CONFIGURATION_DEF_SIZE;
+    char *token;
+    int i, ret, value;
+    u32 config_desc_lock = 0;
+
+    /* reserve one byte for null termination */
+    strbuf = kmalloc(count + 1, GFP_KERNEL);
+    if (!strbuf)
+        return -ENOMEM;
+
+    strbuf_copy = strbuf;
+    strlcpy(strbuf, buf, count + 1);
+
+    /* Just return if bConfigDescrLock is already set */
+    ret = ufshcd_query_attr(hba, UPIU_QUERY_OPCODE_READ_ATTR,
+        QUERY_ATTR_IDN_CONF_DESC_LOCK, 0, 0, &config_desc_lock);
+    if (ret)
+        goto out;
+
+    if (config_desc_lock) {
+        dev_err(hba->dev, "%s: bConfigDescrLock already set to %u,

cannot re-provision device!\n",
+        __func__, config_desc_lock);
+        ret = -EINVAL;
+        goto out;
+    }

drivers/scsi/ufs/ufs-configfs.c new file +17 -0

+
+    for (i = 0; i < QUERY_DESC_CONFIGURATION_DEF_SIZE; i++) {
+        token = strsep(&strbuf, " ");
+        if (!token && i)
+            break;
+
+        ret = kstrtoint(token, 0, &value);
+        if (ret) {
+            dev_err(hba->dev, "%s: kstrtoint failed %d %s\n",
+                __func__, ret, token);
+            ret = -EINVAL;
+            goto out;
+        }
+        desc_buf[i] = (u8)value;
+    }
+
+    /* Write configuration descriptor to provision ufs */

Quoted 8 lines

Quoted 5 lines

+    ret = ufshcd_query_descriptor_retry(hba, UPIU_QUERY_OPCODE_WRITE_DESC, +        QUERY_DESC_IDN_CONFIGURATION, 0, 0, desc_buf, &desc_buf_len); +
+    if (!ret)
+        dev_info(hba->dev, "%s: UFS Provisioning done, reboot now!\n",

That is not necessarily true - bConfDescContinue might have been used or bConfigDescrLock might need to be set.  Better just to say that configuration descriptor 0 was written.

Agree. Will update.

Quoted 45 lines

Quoted 45 lines

+        __func__);

drivers/scsi/ufs/ufs-configfs.c new file +43 -0

+
+out:
+    kfree(strbuf_copy);
+    if (ret)
+        return ret;
+    return count;
+}
+
+static ssize_t ufs_provision_store(struct config_item *item,
+        const char *buf, size_t count)
+{
+    struct ufs_hba *hba = config_item_to_hba(item);
+
+    return ufshcd_desc_configfs_store(hba, buf, count);
+}
+
+static struct configfs_attribute ufshcd_attr_provision = {
+    .ca_name    = "ufs_provision",
+    .ca_mode    = 0644,
+    .ca_owner    = THIS_MODULE,
+    .show        = ufs_provision_show,
+    .store        = ufs_provision_store,
+};
+
+static struct configfs_attribute *ufshcd_attrs[] = {
+    &ufshcd_attr_provision,
+    NULL,
+};
+
+static struct config_item_type ufscfg_type = {
+    .ct_attrs    = ufshcd_attrs,
+    .ct_owner    = THIS_MODULE,
+};
+
+static struct configfs_subsystem ufscfg_subsys = {
+    .su_group = {
+        .cg_item = {
+            .ci_type = &ufscfg_type,
+        },
+    },
+};
+
+void ufshcd_configfs_init(struct ufs_hba *hba, const char *name)

Quoted 8 lines

drivers/scsi/ufs/ufs-configfs.c line 142

Quoted 6 lines

drivers/scsi/ufs/ufs-configfs.c new file +6 -0

+{
+    int ret;
+    struct configfs_subsystem *subsys = &hba->subsys;
+
+    strncpy(ufscfg_subsys.su_group.cg_item.ci_namebuf, name, strlen(name));
+    subsys->su_group = ufscfg_subsys.su_group;

configfs_subsystem cannot share su_group with other configfs_subsystem i.e you are not allowing for there being more than 1 hba

Agree. I think I will have to move above declarations(ufscfg_subsys/ufscfg_type/ufshcd_attrs) in driver .c/.h file (to make it per ufs hba/probe).
Will check and update.

Quoted 75 lines

Quoted 75 lines

+    config_group_init(&subsys->su_group);
+    mutex_init(&subsys->su_mutex);
+    ret = configfs_register_subsystem(subsys);
+    if (ret)
+        pr_err("Error %d while registering subsystem %s\n", +               ret,
+               subsys->su_group.cg_item.ci_namebuf);

drivers/scsi/ufs/ufs-configfs.c new file +6 -0

+}
+
+void ufshcd_configfs_exit(void)
+{
+    configfs_unregister_subsystem(&ufscfg_subsys);
+}

drivers/scsi/ufs/ufshcd.c +2 -1

index e01cdc0..32a67b0 100644
@@ -7711,6 +7711,7 @@ int ufshcd_shutdown(struct ufs_hba *hba)
   void ufshcd_remove(struct ufs_hba *hba)
   {
       ufs_sysfs_remove_nodes(hba->dev);
+    ufshcd_configfs_exit();
       scsi_remove_host(hba->host);
       /* disable interrupts */
       ufshcd_disable_intr(hba, hba->intr_mask);

@@ -7965,7 +7966,7 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem
 *mmio_base, unsigned int irq)
         async_schedule(ufshcd_async_scan, hba);
       ufs_sysfs_add_nodes(hba->dev);
-
+    ufshcd_configfs_init(hba, dev_name(hba->dev));
       return 0;

    out_remove_scsi_host:

drivers/scsi/ufs/ufshcd.h +0 -0

index 45013b6..2275032 100644
@@ -37,6 +37,7 @@
   #ifndef _UFSHCD_H
   #define _UFSHCD_H

  +#include <linux/configfs.h>
  #include <linux/module.h>
  #include <linux/kernel.h>
  #include <linux/init.h>

drivers/scsi/ufs/ufshcd.h +3 -0

@@ -515,6 +516,9 @@ struct ufs_hba {
         struct Scsi_Host *host;
       struct device *dev;
+#ifdef CONFIG_UFS_PROVISION
+    struct configfs_subsystem subsys;
+#endif
       /*
        * This field is to keep a reference to "scsi_device" corresponding to
        * "UFS device" W-LU.

@@ -868,6 +872,19 @@ int ufshcd_read_string_desc(struct ufs_hba *hba, int
 desc_index,
   int ufshcd_hold(struct ufs_hba *hba, bool async);
   void ufshcd_release(struct ufs_hba *hba);

  +/* Expose UFS configfs API's */

drivers/scsi/ufs/ufshcd.h +2 -0

+#ifndef CONFIG_UFS_PROVISION
+static inline void ufshcd_configfs_init(struct ufs_hba *hba, const char

*name)

drivers/scsi/ufs/ufshcd.h +10 -0

+{
+}
+static inline void ufshcd_configfs_exit(void)
+{
+}
+#else
+void ufshcd_configfs_init(struct ufs_hba *hba, const char *name);
+void ufshcd_configfs_exit(void);
+#endif
+

  int ufshcd_map_desc_id_to_length(struct ufs_hba *hba, enum desc_idn desc_id,
      int *desc_length);

Quoted 58 lines · Sayali Lokhande

Hi Adrian,

Quoted 44 lines · Adrian Hunter

Quoted 39 lines · Sayali Lokhande

This patch adds configfs support to provision UFS device at runtime. This feature can be primarily useful in factory or assembly line as some devices may be required to be configured multiple times during initial system development phase. Configuration Descriptors can be written multiple times until bConfigDescrLock attribute is zero.

Configuration descriptor buffer consists of Device and Unit descriptor configurable parameters which are parsed from vendor specific provisioning file and then passed via configfs node at runtime to provision ufs device.
CONFIG_CONFIGFS_FS needs to be enabled for using this feature.

Usage:
1) To read current configuration descriptor :
    cat /config/XXXX.ufshc/ufs_provision
2) To provision ufs device:
    echo <config_desc_buf> > /config/XXXX.ufshc/ufs_provision

Signed-off-by Sayali Lokhande <[email protected]>

---
   Documentation/ABI/testing/configfs-driver-ufs |  18 +++
   drivers/scsi/ufs/Kconfig                      |  10 ++
   drivers/scsi/ufs/Makefile                     |   1 +
   drivers/scsi/ufs/ufs-configfs.c               | 155
++++++++++++++++++++++++++
   drivers/scsi/ufs/ufshcd.c                     |   3 +-
   drivers/scsi/ufs/ufshcd.h                     |  17 +++
   6 files changed, 203 insertions(+), 1 deletion(-)

  create mode 100644 Documentation/ABI/testing/configfs-driver-ufs create mode 100644 drivers/scsi/ufs/ufs-configfs.c

Documentation/ABI/testing/configfs-driver-ufs new file +0 -0

new file mode 100644
index 0000000..eeee499c

Documentation/ABI/testing/configfs-driver-ufs line 1

Quoted 1 line

Documentation/ABI/testing/configfs-driver-ufs new file +1 -0

@@ -0,0 +1,18 @@
+What:        /config/ufshcd/ufs_provision

You are using the device name as the config subsystem name, so this is really:

Quoted 1 line

    What:        /config/*/ufs_provision

Agree. Will update.

Quoted 3 lines

Documentation/ABI/testing/configfs-driver-ufs line 3

Quoted 2 lines

Documentation/ABI/testing/configfs-driver-ufs new file +2 -0

+Date:        Jun 2018
+KernelVersion:    4.14

4.19 maybe

Done.

Quoted 5 lines

Quoted 3 lines

Documentation/ABI/testing/configfs-driver-ufs new file +2 -0

+Description:
+        This file shows the current ufs configuration descriptor set in

device.

It is only the first config descriptor though isn't it?  There is no support for the other 3.  Shouldn't we support config descriptors fully?

Quoted 7 lines

Yes, we should support config descriptors fully. My current implementation only supports config desc (index = 00h).
I m thinking I can add separate "index" field along with "ufs_provision" field and can use this index (instead of hard coding to 0)
to write repective config_desc. In this way, we should first set the "index" and then read/write to "ufs_provision".
Let me know if you have any concern with this approach ?

One file for each config descriptor would seem more normal.

Quoted 82 lines

Quoted 9 lines

Quoted 8 lines

+        This can be used to provision ufs device if bConfigDescrLock is 0. +        For more details, refer 14.1.6.3 Configuration Descriptor and +        Table 14-12 - Unit Descriptor configurable parameters from specs for
+        description of each configuration descriptor parameter. +        Configuration descriptor buffer needs to be passed in space separated
+        format specificied as below:

specificied -> specified

Done

Quoted 10 lines

Quoted 7 lines

+        echo <bLength> <bDescriptorIDN> <bConfDescContinue> <bBootEnable> +        <bDescrAccessEn> <bInitPowerMode> <bHighPriorityLUN> +        <bSecureRemovalType> <bInitActiveICCLevel> <wPeriodicRTCUpdate> +        <0Bh:0Fh_ReservedAs_0> <bLUEnable> <bBootLunID> <bLUWriteProtect> +        <bMemoryType> <dNumAllocUnits> <bDataReliability> <bLogicalBlockSize>
+        <bProvisioningType> <wContextCapabilities> <0Dh:0Fh_ReservedAs_0>

This format is not exactly correct anymore because each byte has to be represented separately.  Also theoretically it can be change, so maybe better just to refer the user to the UFS specification.

Agree. Will update to just refer to UFS spec (for Config_desc format).

Quoted 60 lines

Quoted 49 lines

+        > /config/XXXX.ufshc/ufs_provision

drivers/scsi/ufs/Kconfig +10 -0

index e27b4d4..a9a0a58 100644
@@ -100,3 +100,13 @@ config SCSI_UFS_QCOM
           Select this if you have UFS controller on QCOM chipset.
         If unsure, say N.
+
+config UFS_PROVISION
+    tristate "Runtime UFS Provisioning support"
+    depends on SCSI_UFSHCD && CONFIGFS_FS
+    help
+      This enables runtime UFS provisioning support. This can be used
+      primarily during assembly line as some devices may be required to
+      be configured multiple times during initial development phase.
+
+      If unsure, say N.

drivers/scsi/ufs/Makefile +0 -0

index 918f579..00110ea 100644
@@ -5,5 +5,6 @@ obj-$(CONFIG_SCSI_UFS_DWC_TC_PLATFORM) +=

tc-dwc-g210-pltfrm.o ufshcd-dwc.o tc-d
  obj-$(CONFIG_SCSI_UFS_QCOM) += ufs-qcom.o
  obj-$(CONFIG_SCSI_UFSHCD) += ufshcd-core.o
  ufshcd-core-objs := ufshcd.o ufs-sysfs.o

drivers/scsi/ufs/Makefile +1 -0

+obj-$(CONFIG_UFS_PROVISION) += ufs-configfs.o
   obj-$(CONFIG_SCSI_UFSHCD_PCI) += ufshcd-pci.o
   obj-$(CONFIG_SCSI_UFSHCD_PLATFORM) += ufshcd-pltfrm.o

drivers/scsi/ufs/ufs-configfs.c new file +12 -0

new file mode 100644
index 0000000..74563a4
@@ -0,0 +1,155 @@
+// SPDX-License-Identifier: GPL-2.0+
+// Copyright (c) 2018, Linux Foundation.
+
+#include <linux/configfs.h>
+#include <linux/err.h>
+#include <linux/string.h>
+
+#include "ufs.h"
+#include "ufshcd.h"
+
+static inline struct ufs_hba *config_item_to_hba(struct config_item *item)
+{

drivers/scsi/ufs/ufs-configfs.c line 22

Quoted 10 lines

drivers/scsi/ufs/ufs-configfs.c new file +10 -0

+    struct config_group *group = to_config_group(item);
+    struct configfs_subsystem *subsys = to_configfs_subsystem(group);
+    struct ufs_hba *hba = container_of(subsys, struct ufs_hba, subsys);
+
+    return subsys ? hba : NULL;
+}
+
+static ssize_t ufs_provision_show(struct config_item *item, char *buf)
+{
+    u8 desc_buf[QUERY_DESC_CONFIGURATION_DEF_SIZE] = {0};

Is it really ok to hard-code the descriptor size?

Quoted 2 lines

I will use ufshcd_read_desc_length() api for each index as required. Will remove this hard-code.

Alternatively, I see there is already hba->desc_size.conf_desc

Quoted 208 lines

Quoted 67 lines

Quoted 67 lines

drivers/scsi/ufs/ufs-configfs.c new file +44 -0

+    int desc_buf_len = QUERY_DESC_CONFIGURATION_DEF_SIZE;
+    int i, ret, curr_len = 0;
+    struct ufs_hba *hba = config_item_to_hba(item);
+
+    ret = ufshcd_query_descriptor_retry(hba, UPIU_QUERY_OPCODE_READ_DESC,
+        QUERY_DESC_IDN_CONFIGURATION, 0, 0, desc_buf, &desc_buf_len);
+
+    if (ret)
+        return ret;
+
+    for (i = 0; i < desc_buf_len; i++)
+        curr_len += snprintf((buf + curr_len), (PAGE_SIZE - curr_len),
+                "0x%x ", desc_buf[i]);
+
+    return curr_len;
+}
+
+ssize_t ufshcd_desc_configfs_store(struct ufs_hba *hba,
+        const char *buf, size_t count)
+{
+    char *strbuf;
+    char *strbuf_copy;
+    u8 desc_buf[QUERY_DESC_CONFIGURATION_DEF_SIZE] = {0};
+    int desc_buf_len = QUERY_DESC_CONFIGURATION_DEF_SIZE;
+    char *token;
+    int i, ret, value;
+    u32 config_desc_lock = 0;
+
+    /* reserve one byte for null termination */
+    strbuf = kmalloc(count + 1, GFP_KERNEL);
+    if (!strbuf)
+        return -ENOMEM;
+
+    strbuf_copy = strbuf;
+    strlcpy(strbuf, buf, count + 1);
+
+    /* Just return if bConfigDescrLock is already set */
+    ret = ufshcd_query_attr(hba, UPIU_QUERY_OPCODE_READ_ATTR,
+        QUERY_ATTR_IDN_CONF_DESC_LOCK, 0, 0, &config_desc_lock);
+    if (ret)
+        goto out;
+
+    if (config_desc_lock) {
+        dev_err(hba->dev, "%s: bConfigDescrLock already set to %u,

cannot re-provision device!\n",
+        __func__, config_desc_lock);
+        ret = -EINVAL;
+        goto out;
+    }

drivers/scsi/ufs/ufs-configfs.c new file +17 -0

+
+    for (i = 0; i < QUERY_DESC_CONFIGURATION_DEF_SIZE; i++) {
+        token = strsep(&strbuf, " ");
+        if (!token && i)
+            break;
+
+        ret = kstrtoint(token, 0, &value);
+        if (ret) {
+            dev_err(hba->dev, "%s: kstrtoint failed %d %s\n",
+                __func__, ret, token);
+            ret = -EINVAL;
+            goto out;
+        }
+        desc_buf[i] = (u8)value;
+    }
+
+    /* Write configuration descriptor to provision ufs */

Quoted 8 lines

Quoted 5 lines

+    ret = ufshcd_query_descriptor_retry(hba, UPIU_QUERY_OPCODE_WRITE_DESC, +        QUERY_DESC_IDN_CONFIGURATION, 0, 0, desc_buf, &desc_buf_len); +
+    if (!ret)
+        dev_info(hba->dev, "%s: UFS Provisioning done, reboot now!\n",

That is not necessarily true - bConfDescContinue might have been used or bConfigDescrLock might need to be set.  Better just to say that configuration descriptor 0 was written.

Agree. Will update.

Quoted 44 lines

Quoted 44 lines

+        __func__);

drivers/scsi/ufs/ufs-configfs.c new file +43 -0

+
+out:
+    kfree(strbuf_copy);
+    if (ret)
+        return ret;
+    return count;
+}
+
+static ssize_t ufs_provision_store(struct config_item *item,
+        const char *buf, size_t count)
+{
+    struct ufs_hba *hba = config_item_to_hba(item);
+
+    return ufshcd_desc_configfs_store(hba, buf, count);
+}
+
+static struct configfs_attribute ufshcd_attr_provision = {
+    .ca_name    = "ufs_provision",
+    .ca_mode    = 0644,
+    .ca_owner    = THIS_MODULE,
+    .show        = ufs_provision_show,
+    .store        = ufs_provision_store,
+};
+
+static struct configfs_attribute *ufshcd_attrs[] = {
+    &ufshcd_attr_provision,
+    NULL,
+};
+
+static struct config_item_type ufscfg_type = {
+    .ct_attrs    = ufshcd_attrs,
+    .ct_owner    = THIS_MODULE,
+};
+
+static struct configfs_subsystem ufscfg_subsys = {
+    .su_group = {
+        .cg_item = {
+            .ci_type = &ufscfg_type,
+        },
+    },
+};
+
+void ufshcd_configfs_init(struct ufs_hba *hba, const char *name)

Quoted 8 lines

drivers/scsi/ufs/ufs-configfs.c line 142

Quoted 6 lines

drivers/scsi/ufs/ufs-configfs.c new file +6 -0

+{
+    int ret;
+    struct configfs_subsystem *subsys = &hba->subsys;
+
+    strncpy(ufscfg_subsys.su_group.cg_item.ci_namebuf, name, strlen(name));
+    subsys->su_group = ufscfg_subsys.su_group;

configfs_subsystem cannot share su_group with other configfs_subsystem i.e you are not allowing for there being more than 1 hba

Agree. I think I will have to move above declarations(ufscfg_subsys/ufscfg_type/ufshcd_attrs) in driver .c/.h file (to make it per ufs hba/probe).
Will check and update.

Quoted 75 lines

Quoted 75 lines

+    config_group_init(&subsys->su_group);
+    mutex_init(&subsys->su_mutex);
+    ret = configfs_register_subsystem(subsys);
+    if (ret)
+        pr_err("Error %d while registering subsystem %s\n", +               ret,
+               subsys->su_group.cg_item.ci_namebuf);

drivers/scsi/ufs/ufs-configfs.c new file +6 -0

+}
+
+void ufshcd_configfs_exit(void)
+{
+    configfs_unregister_subsystem(&ufscfg_subsys);
+}

drivers/scsi/ufs/ufshcd.c +2 -1

index e01cdc0..32a67b0 100644
@@ -7711,6 +7711,7 @@ int ufshcd_shutdown(struct ufs_hba *hba)
   void ufshcd_remove(struct ufs_hba *hba)
   {
       ufs_sysfs_remove_nodes(hba->dev);
+    ufshcd_configfs_exit();
       scsi_remove_host(hba->host);
       /* disable interrupts */
       ufshcd_disable_intr(hba, hba->intr_mask);

@@ -7965,7 +7966,7 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem
 *mmio_base, unsigned int irq)
         async_schedule(ufshcd_async_scan, hba);
       ufs_sysfs_add_nodes(hba->dev);
-
+    ufshcd_configfs_init(hba, dev_name(hba->dev));
       return 0;
     out_remove_scsi_host:

drivers/scsi/ufs/ufshcd.h +15 -0

index 45013b6..2275032 100644
@@ -37,6 +37,7 @@
   #ifndef _UFSHCD_H
   #define _UFSHCD_H
   +#include <linux/configfs.h>
   #include <linux/module.h>
   #include <linux/kernel.h>
   #include <linux/init.h>

@@ -515,6 +516,9 @@ struct ufs_hba {
         struct Scsi_Host *host;
       struct device *dev;
+#ifdef CONFIG_UFS_PROVISION
+    struct configfs_subsystem subsys;
+#endif
       /*
        * This field is to keep a reference to "scsi_device" corresponding to
        * "UFS device" W-LU.

@@ -868,6 +872,19 @@ int ufshcd_read_string_desc(struct ufs_hba *hba, int
 desc_index,
   int ufshcd_hold(struct ufs_hba *hba, bool async);
   void ufshcd_release(struct ufs_hba *hba);
   +/* Expose UFS configfs API's */
+#ifndef CONFIG_UFS_PROVISION
+static inline void ufshcd_configfs_init(struct ufs_hba *hba, const char
 *name)
+{
+}
+static inline void ufshcd_configfs_exit(void)
+{
+}
+#else
+void ufshcd_configfs_init(struct ufs_hba *hba, const char *name);
+void ufshcd_configfs_exit(void);
+#endif
+
   int ufshcd_map_desc_id_to_length(struct ufs_hba *hba, enum desc_idn

desc_id,
      int *desc_length);

Quoted 60 lines · Adrian Hunter

Quoted 59 lines · Sayali Lokhande

Hi Adrian,

Quoted 44 lines · Adrian Hunter

Quoted 39 lines · Sayali Lokhande

This patch adds configfs support to provision UFS device at runtime. This feature can be primarily useful in factory or assembly line as some devices may be required to be configured multiple times during initial system development phase. Configuration Descriptors can be written multiple times until bConfigDescrLock attribute is zero.

Configuration descriptor buffer consists of Device and Unit descriptor configurable parameters which are parsed from vendor specific provisioning file and then passed via configfs node at runtime to provision ufs device.
CONFIG_CONFIGFS_FS needs to be enabled for using this feature.

Usage:
1) To read current configuration descriptor :
     cat /config/XXXX.ufshc/ufs_provision
2) To provision ufs device:
     echo <config_desc_buf> > /config/XXXX.ufshc/ufs_provision

Signed-off-by Sayali Lokhande <[email protected]>

---
   Documentation/ABI/testing/configfs-driver-ufs |  18 +++ drivers/scsi/ufs/Kconfig                      |  10 ++ drivers/scsi/ufs/Makefile                     |   1 + drivers/scsi/ufs/ufs-configfs.c               | 155
++++++++++++++++++++++++++
   drivers/scsi/ufs/ufshcd.c                     |   3 +- drivers/scsi/ufs/ufshcd.h                     |  17 +++

   6 files changed, 203 insertions(+), 1 deletion(-)

   create mode 100644 Documentation/ABI/testing/configfs-driver-ufs create mode 100644 drivers/scsi/ufs/ufs-configfs.c

Documentation/ABI/testing/configfs-driver-ufs new file +0 -0

new file mode 100644
index 0000000..eeee499c

Documentation/ABI/testing/configfs-driver-ufs line 1

Quoted 1 line

Documentation/ABI/testing/configfs-driver-ufs new file +1 -0

@@ -0,0 +1,18 @@
+What:        /config/ufshcd/ufs_provision

You are using the device name as the config subsystem name, so this is really:

Quoted 1 line

     What:        /config/*/ufs_provision

Agree. Will update.

Quoted 3 lines

Documentation/ABI/testing/configfs-driver-ufs line 3

Quoted 2 lines

Documentation/ABI/testing/configfs-driver-ufs new file +2 -0

+Date:        Jun 2018
+KernelVersion:    4.14

4.19 maybe

Done.

Quoted 6 lines

Quoted 3 lines

Documentation/ABI/testing/configfs-driver-ufs new file +2 -0

+Description:
+        This file shows the current ufs configuration descriptor set in

device.

It is only the first config descriptor though isn't it?  There is no support
for the other 3.  Shouldn't we support config descriptors fully?

Quoted 8 lines

Quoted 7 lines

Yes, we should support config descriptors fully. My current implementation only supports config desc (index = 00h).
I m thinking I can add separate "index" field along with "ufs_provision" field and can use this index (instead of hard coding to 0)
to write repective config_desc. In this way, we should first set the "index" and then read/write to "ufs_provision".
Let me know if you have any concern with this approach ?

One file for each config descriptor would seem more normal.

I can make separate file for each config descriptor index(say ufs_provision_0/1/2/3), but still show() and store() api's can remain common. Will try it out and update.

Quoted 84 lines

Quoted 84 lines

Quoted 10 lines

Quoted 9 lines

+        This can be used to provision ufs device if bConfigDescrLock is 0.
+        For more details, refer 14.1.6.3 Configuration Descriptor and +        Table 14-12 - Unit Descriptor configurable parameters from specs for
+        description of each configuration descriptor parameter. +        Configuration descriptor buffer needs to be passed in space separated
+        format specificied as below:

specificied -> specified

Done

Quoted 10 lines

Quoted 7 lines

+        echo <bLength> <bDescriptorIDN> <bConfDescContinue> <bBootEnable> +        <bDescrAccessEn> <bInitPowerMode> <bHighPriorityLUN> +        <bSecureRemovalType> <bInitActiveICCLevel> <wPeriodicRTCUpdate> +        <0Bh:0Fh_ReservedAs_0> <bLUEnable> <bBootLunID> <bLUWriteProtect> +        <bMemoryType> <dNumAllocUnits> <bDataReliability> <bLogicalBlockSize>
+        <bProvisioningType> <wContextCapabilities> <0Dh:0Fh_ReservedAs_0>

This format is not exactly correct anymore because each byte has to be represented separately.  Also theoretically it can be change, so maybe better just to refer the user to the UFS specification.

Agree. Will update to just refer to UFS spec (for Config_desc format).

Quoted 61 lines

Quoted 50 lines

+        > /config/XXXX.ufshc/ufs_provision

drivers/scsi/ufs/Kconfig +0 -0

index e27b4d4..a9a0a58 100644
@@ -100,3 +100,13 @@ config SCSI_UFS_QCOM

           Select this if you have UFS controller on QCOM chipset. If unsure, say N.

drivers/scsi/ufs/Kconfig +10 -0

+
+config UFS_PROVISION
+    tristate "Runtime UFS Provisioning support"
+    depends on SCSI_UFSHCD && CONFIGFS_FS
+    help
+      This enables runtime UFS provisioning support. This can be used
+      primarily during assembly line as some devices may be required to
+      be configured multiple times during initial development phase.
+
+      If unsure, say N.

drivers/scsi/ufs/Makefile +0 -0

index 918f579..00110ea 100644
@@ -5,5 +5,6 @@ obj-$(CONFIG_SCSI_UFS_DWC_TC_PLATFORM) +=

tc-dwc-g210-pltfrm.o ufshcd-dwc.o tc-d obj-$(CONFIG_SCSI_UFS_QCOM) += ufs-qcom.o obj-$(CONFIG_SCSI_UFSHCD) += ufshcd-core.o ufshcd-core-objs := ufshcd.o ufs-sysfs.o +obj-$(CONFIG_UFS_PROVISION) += ufs-configfs.o obj-$(CONFIG_SCSI_UFSHCD_PCI) += ufshcd-pci.o obj-$(CONFIG_SCSI_UFSHCD_PLATFORM) += ufshcd-pltfrm.o

drivers/scsi/ufs/ufs-configfs.c new file +11 -0

new file mode 100644
index 0000000..74563a4
@@ -0,0 +1,155 @@
+// SPDX-License-Identifier: GPL-2.0+
+// Copyright (c) 2018, Linux Foundation.
+
+#include <linux/configfs.h>
+#include <linux/err.h>
+#include <linux/string.h>
+
+#include "ufs.h"
+#include "ufshcd.h"
+
+static inline struct ufs_hba *config_item_to_hba(struct config_item

*item)

drivers/scsi/ufs/ufs-configfs.c new file +1 -0

+{

drivers/scsi/ufs/ufs-configfs.c line 22

Quoted 10 lines

drivers/scsi/ufs/ufs-configfs.c new file +10 -0

+    struct config_group *group = to_config_group(item);
+    struct configfs_subsystem *subsys = to_configfs_subsystem(group);
+    struct ufs_hba *hba = container_of(subsys, struct ufs_hba, subsys);
+
+    return subsys ? hba : NULL;
+}
+
+static ssize_t ufs_provision_show(struct config_item *item, char *buf)
+{
+    u8 desc_buf[QUERY_DESC_CONFIGURATION_DEF_SIZE] = {0};

Is it really ok to hard-code the descriptor size?

Quoted 3 lines

Quoted 2 lines

I will use ufshcd_read_desc_length() api for each index as required. Will remove this hard-code.

Alternatively, I see there is already hba->desc_size.conf_desc

hba->desc_size.conf_desc is actually size for index 0. I thought what if desc size various per index.
So better to read for each index. What say ?

Quoted 211 lines

Quoted 211 lines

Quoted 68 lines

Quoted 68 lines

+    int desc_buf_len = QUERY_DESC_CONFIGURATION_DEF_SIZE; +    int i, ret, curr_len = 0;
+    struct ufs_hba *hba = config_item_to_hba(item);

drivers/scsi/ufs/ufs-configfs.c new file +41 -0

+
+    ret = ufshcd_query_descriptor_retry(hba, UPIU_QUERY_OPCODE_READ_DESC,
+        QUERY_DESC_IDN_CONFIGURATION, 0, 0, desc_buf, &desc_buf_len);
+
+    if (ret)
+        return ret;
+
+    for (i = 0; i < desc_buf_len; i++)
+        curr_len += snprintf((buf + curr_len), (PAGE_SIZE - curr_len),
+                "0x%x ", desc_buf[i]);
+
+    return curr_len;
+}
+
+ssize_t ufshcd_desc_configfs_store(struct ufs_hba *hba,
+        const char *buf, size_t count)
+{
+    char *strbuf;
+    char *strbuf_copy;
+    u8 desc_buf[QUERY_DESC_CONFIGURATION_DEF_SIZE] = {0};
+    int desc_buf_len = QUERY_DESC_CONFIGURATION_DEF_SIZE;
+    char *token;
+    int i, ret, value;
+    u32 config_desc_lock = 0;
+
+    /* reserve one byte for null termination */
+    strbuf = kmalloc(count + 1, GFP_KERNEL);
+    if (!strbuf)
+        return -ENOMEM;
+
+    strbuf_copy = strbuf;
+    strlcpy(strbuf, buf, count + 1);
+
+    /* Just return if bConfigDescrLock is already set */
+    ret = ufshcd_query_attr(hba, UPIU_QUERY_OPCODE_READ_ATTR,
+        QUERY_ATTR_IDN_CONF_DESC_LOCK, 0, 0, &config_desc_lock);
+    if (ret)
+        goto out;
+
+    if (config_desc_lock) {
+        dev_err(hba->dev, "%s: bConfigDescrLock already set to %u,

cannot re-provision device!\n",
+        __func__, config_desc_lock);
+        ret = -EINVAL;
+        goto out;
+    }

drivers/scsi/ufs/ufs-configfs.c new file +18 -0

+
+    for (i = 0; i < QUERY_DESC_CONFIGURATION_DEF_SIZE; i++) {
+        token = strsep(&strbuf, " ");
+        if (!token && i)
+            break;
+
+        ret = kstrtoint(token, 0, &value);
+        if (ret) {
+            dev_err(hba->dev, "%s: kstrtoint failed %d %s\n",
+                __func__, ret, token);
+            ret = -EINVAL;
+            goto out;
+        }
+        desc_buf[i] = (u8)value;
+    }
+
+    /* Write configuration descriptor to provision ufs */
+    ret = ufshcd_query_descriptor_retry(hba,

Quoted 8 lines

Quoted 5 lines

UPIU_QUERY_OPCODE_WRITE_DESC,
+        QUERY_DESC_IDN_CONFIGURATION, 0, 0, desc_buf, &desc_buf_len); +
+    if (!ret)
+        dev_info(hba->dev, "%s: UFS Provisioning done, reboot now!\n",

That is not necessarily true - bConfDescContinue might have been used or bConfigDescrLock might need to be set.  Better just to say that configuration descriptor 0 was written.

Agree. Will update.

Quoted 45 lines

Quoted 45 lines

+        __func__);

drivers/scsi/ufs/ufs-configfs.c new file +44 -0

+
+out:
+    kfree(strbuf_copy);
+    if (ret)
+        return ret;
+    return count;
+}
+
+static ssize_t ufs_provision_store(struct config_item *item,
+        const char *buf, size_t count)
+{
+    struct ufs_hba *hba = config_item_to_hba(item);
+
+    return ufshcd_desc_configfs_store(hba, buf, count);
+}
+
+static struct configfs_attribute ufshcd_attr_provision = {
+    .ca_name    = "ufs_provision",
+    .ca_mode    = 0644,
+    .ca_owner    = THIS_MODULE,
+    .show        = ufs_provision_show,
+    .store        = ufs_provision_store,
+};
+
+static struct configfs_attribute *ufshcd_attrs[] = {
+    &ufshcd_attr_provision,
+    NULL,
+};
+
+static struct config_item_type ufscfg_type = {
+    .ct_attrs    = ufshcd_attrs,
+    .ct_owner    = THIS_MODULE,
+};
+
+static struct configfs_subsystem ufscfg_subsys = {
+    .su_group = {
+        .cg_item = {
+            .ci_type = &ufscfg_type,
+        },
+    },
+};
+
+void ufshcd_configfs_init(struct ufs_hba *hba, const char *name)
+{

Quoted 8 lines

Quoted 6 lines

+    int ret;
+    struct configfs_subsystem *subsys = &hba->subsys; +
+    strncpy(ufscfg_subsys.su_group.cg_item.ci_namebuf, name, strlen(name));
+    subsys->su_group = ufscfg_subsys.su_group;

configfs_subsystem cannot share su_group with other configfs_subsystem i.e you are not allowing for there being more than 1 hba

Agree. I think I will have to move above declarations(ufscfg_subsys/ufscfg_type/ufshcd_attrs) in driver .c/.h file (to make it per ufs hba/probe).
Will check and update.

Quoted 76 lines

Quoted 76 lines

+    config_group_init(&subsys->su_group);
+    mutex_init(&subsys->su_mutex);
+    ret = configfs_register_subsystem(subsys);
+    if (ret)
+        pr_err("Error %d while registering subsystem %s\n", +               ret,
+               subsys->su_group.cg_item.ci_namebuf);

drivers/scsi/ufs/ufs-configfs.c new file +6 -0

+}
+
+void ufshcd_configfs_exit(void)
+{
+    configfs_unregister_subsystem(&ufscfg_subsys);
+}

drivers/scsi/ufs/ufshcd.c +2 -1

index e01cdc0..32a67b0 100644
@@ -7711,6 +7711,7 @@ int ufshcd_shutdown(struct ufs_hba *hba)
    void ufshcd_remove(struct ufs_hba *hba)
    {
        ufs_sysfs_remove_nodes(hba->dev);
+    ufshcd_configfs_exit();
        scsi_remove_host(hba->host);
        /* disable interrupts */
        ufshcd_disable_intr(hba, hba->intr_mask);

@@ -7965,7 +7966,7 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem
 *mmio_base, unsigned int irq)
          async_schedule(ufshcd_async_scan, hba);
        ufs_sysfs_add_nodes(hba->dev);
-
+    ufshcd_configfs_init(hba, dev_name(hba->dev));
        return 0;

     out_remove_scsi_host:

drivers/scsi/ufs/ufshcd.h +0 -0

index 45013b6..2275032 100644
@@ -37,6 +37,7 @@
    #ifndef _UFSHCD_H
    #define _UFSHCD_H

   +#include <linux/configfs.h>
   #include <linux/module.h>
   #include <linux/kernel.h>
   #include <linux/init.h>

drivers/scsi/ufs/ufshcd.h +3 -0

@@ -515,6 +516,9 @@ struct ufs_hba {
          struct Scsi_Host *host;
        struct device *dev;
+#ifdef CONFIG_UFS_PROVISION
+    struct configfs_subsystem subsys;
+#endif
        /*
         * This field is to keep a reference to "scsi_device"

corresponding to
        * "UFS device" W-LU.

drivers/scsi/ufs/ufshcd.h +0 -0

@@ -868,6 +872,19 @@ int ufshcd_read_string_desc(struct ufs_hba *hba, int
 desc_index,
    int ufshcd_hold(struct ufs_hba *hba, bool async);
    void ufshcd_release(struct ufs_hba *hba);

   +/* Expose UFS configfs API's */

drivers/scsi/ufs/ufshcd.h +2 -0

+#ifndef CONFIG_UFS_PROVISION
+static inline void ufshcd_configfs_init(struct ufs_hba *hba, const char

*name)

drivers/scsi/ufs/ufshcd.h +10 -0

+{
+}
+static inline void ufshcd_configfs_exit(void)
+{
+}
+#else
+void ufshcd_configfs_init(struct ufs_hba *hba, const char *name);
+void ufshcd_configfs_exit(void);
+#endif
+

   int ufshcd_map_desc_id_to_length(struct ufs_hba *hba, enum desc_idn desc_id,
       int *desc_length);

Quoted 156 lines · Sayali Lokhande

Quoted 60 lines · Adrian Hunter

Quoted 59 lines · Sayali Lokhande

Hi Adrian,

Quoted 44 lines · Adrian Hunter

Quoted 39 lines · Sayali Lokhande

This patch adds configfs support to provision UFS device at runtime. This feature can be primarily useful in factory or assembly line as some devices may be required to be configured multiple times during initial system development phase. Configuration Descriptors can be written multiple times until bConfigDescrLock attribute is zero.

Configuration descriptor buffer consists of Device and Unit descriptor configurable parameters which are parsed from vendor specific provisioning file and then passed via configfs node at runtime to provision ufs device.
CONFIG_CONFIGFS_FS needs to be enabled for using this feature.

Usage:
1) To read current configuration descriptor :
     cat /config/XXXX.ufshc/ufs_provision
2) To provision ufs device:
     echo <config_desc_buf> > /config/XXXX.ufshc/ufs_provision

Signed-off-by Sayali Lokhande <[email protected]>

---
    Documentation/ABI/testing/configfs-driver-ufs |  18 +++
    drivers/scsi/ufs/Kconfig                      |  10 ++
    drivers/scsi/ufs/Makefile                     |   1 +
    drivers/scsi/ufs/ufs-configfs.c               | 155
++++++++++++++++++++++++++
    drivers/scsi/ufs/ufshcd.c                     |   3 +-
    drivers/scsi/ufs/ufshcd.h                     |  17 +++
    6 files changed, 203 insertions(+), 1 deletion(-)

   create mode 100644 Documentation/ABI/testing/configfs-driver-ufs create mode 100644 drivers/scsi/ufs/ufs-configfs.c

Documentation/ABI/testing/configfs-driver-ufs new file +0 -0

new file mode 100644
index 0000000..eeee499c

Documentation/ABI/testing/configfs-driver-ufs line 1

Quoted 1 line

Documentation/ABI/testing/configfs-driver-ufs new file +1 -0

@@ -0,0 +1,18 @@
+What:        /config/ufshcd/ufs_provision

You are using the device name as the config subsystem name, so this is really:

Quoted 1 line

     What:        /config/*/ufs_provision

Agree. Will update.

Quoted 3 lines

Documentation/ABI/testing/configfs-driver-ufs line 3

Quoted 2 lines

Documentation/ABI/testing/configfs-driver-ufs new file +2 -0

+Date:        Jun 2018
+KernelVersion:    4.14

4.19 maybe

Done.

Quoted 6 lines

Quoted 3 lines

Documentation/ABI/testing/configfs-driver-ufs new file +2 -0

+Description:
+        This file shows the current ufs configuration descriptor set in

device.

It is only the first config descriptor though isn't it?  There is no support
for the other 3.  Shouldn't we support config descriptors fully?

Quoted 8 lines

Quoted 7 lines

Yes, we should support config descriptors fully. My current implementation only supports config desc (index = 00h).
I m thinking I can add separate "index" field along with "ufs_provision" field and can use this index (instead of hard coding to 0)
to write repective config_desc. In this way, we should first set the "index" and then read/write to "ufs_provision".
Let me know if you have any concern with this approach ?

One file for each config descriptor would seem more normal.

I can make separate file for each config descriptor index(say ufs_provision_0/1/2/3), but still show() and store() api's can remain common. Will try it out and update.

Quoted 84 lines

Quoted 84 lines

Quoted 10 lines

Quoted 9 lines

+        This can be used to provision ufs device if bConfigDescrLock is 0.
+        For more details, refer 14.1.6.3 Configuration Descriptor and +        Table 14-12 - Unit Descriptor configurable parameters from specs for
+        description of each configuration descriptor parameter. +        Configuration descriptor buffer needs to be passed in space separated
+        format specificied as below:

specificied -> specified

Done

Quoted 10 lines

Quoted 7 lines

+        echo <bLength> <bDescriptorIDN> <bConfDescContinue> <bBootEnable> +        <bDescrAccessEn> <bInitPowerMode> <bHighPriorityLUN> +        <bSecureRemovalType> <bInitActiveICCLevel> <wPeriodicRTCUpdate> +        <0Bh:0Fh_ReservedAs_0> <bLUEnable> <bBootLunID> <bLUWriteProtect> +        <bMemoryType> <dNumAllocUnits> <bDataReliability> <bLogicalBlockSize>
+        <bProvisioningType> <wContextCapabilities> <0Dh:0Fh_ReservedAs_0>

This format is not exactly correct anymore because each byte has to be represented separately.  Also theoretically it can be change, so maybe better just to refer the user to the UFS specification.

Agree. Will update to just refer to UFS spec (for Config_desc format).

Quoted 61 lines

Quoted 50 lines

+        > /config/XXXX.ufshc/ufs_provision

drivers/scsi/ufs/Kconfig +10 -0

index e27b4d4..a9a0a58 100644
@@ -100,3 +100,13 @@ config SCSI_UFS_QCOM
            Select this if you have UFS controller on QCOM chipset.
          If unsure, say N.
+
+config UFS_PROVISION
+    tristate "Runtime UFS Provisioning support"
+    depends on SCSI_UFSHCD && CONFIGFS_FS
+    help
+      This enables runtime UFS provisioning support. This can be used
+      primarily during assembly line as some devices may be required to
+      be configured multiple times during initial development phase.
+
+      If unsure, say N.

drivers/scsi/ufs/Makefile +0 -0

index 918f579..00110ea 100644
@@ -5,5 +5,6 @@ obj-$(CONFIG_SCSI_UFS_DWC_TC_PLATFORM) +=

tc-dwc-g210-pltfrm.o ufshcd-dwc.o tc-d
   obj-$(CONFIG_SCSI_UFS_QCOM) += ufs-qcom.o
   obj-$(CONFIG_SCSI_UFSHCD) += ufshcd-core.o
   ufshcd-core-objs := ufshcd.o ufs-sysfs.o

drivers/scsi/ufs/Makefile +1 -0

+obj-$(CONFIG_UFS_PROVISION) += ufs-configfs.o
    obj-$(CONFIG_SCSI_UFSHCD_PCI) += ufshcd-pci.o
    obj-$(CONFIG_SCSI_UFSHCD_PLATFORM) += ufshcd-pltfrm.o

drivers/scsi/ufs/ufs-configfs.c new file +11 -0

new file mode 100644
index 0000000..74563a4
@@ -0,0 +1,155 @@
+// SPDX-License-Identifier: GPL-2.0+
+// Copyright (c) 2018, Linux Foundation.
+
+#include <linux/configfs.h>
+#include <linux/err.h>
+#include <linux/string.h>
+
+#include "ufs.h"
+#include "ufshcd.h"
+
+static inline struct ufs_hba *config_item_to_hba(struct config_item

*item)

drivers/scsi/ufs/ufs-configfs.c new file +1 -0

+{

drivers/scsi/ufs/ufs-configfs.c line 22

Quoted 10 lines

drivers/scsi/ufs/ufs-configfs.c new file +10 -0

+    struct config_group *group = to_config_group(item);
+    struct configfs_subsystem *subsys = to_configfs_subsystem(group);
+    struct ufs_hba *hba = container_of(subsys, struct ufs_hba, subsys);
+
+    return subsys ? hba : NULL;
+}
+
+static ssize_t ufs_provision_show(struct config_item *item, char *buf)
+{
+    u8 desc_buf[QUERY_DESC_CONFIGURATION_DEF_SIZE] = {0};

Is it really ok to hard-code the descriptor size?

Quoted 6 lines

Quoted 3 lines

Quoted 2 lines

I will use ufshcd_read_desc_length() api for each index as required. Will remove this hard-code.

Alternatively, I see there is already hba->desc_size.conf_desc

hba->desc_size.conf_desc is actually size for index 0. I thought what if desc size various per index.
So better to read for each index. What say ?

Based on the 'B' and 'L' values defined in the spec., all configuration descriptors have the same length.

Quoted 210 lines

Quoted 209 lines

Quoted 209 lines

Quoted 67 lines

Quoted 67 lines

+    int desc_buf_len = QUERY_DESC_CONFIGURATION_DEF_SIZE; +    int i, ret, curr_len = 0;
+    struct ufs_hba *hba = config_item_to_hba(item);

drivers/scsi/ufs/ufs-configfs.c new file +41 -0

+
+    ret = ufshcd_query_descriptor_retry(hba, UPIU_QUERY_OPCODE_READ_DESC,
+        QUERY_DESC_IDN_CONFIGURATION, 0, 0, desc_buf, &desc_buf_len);
+
+    if (ret)
+        return ret;
+
+    for (i = 0; i < desc_buf_len; i++)
+        curr_len += snprintf((buf + curr_len), (PAGE_SIZE - curr_len),
+                "0x%x ", desc_buf[i]);
+
+    return curr_len;
+}
+
+ssize_t ufshcd_desc_configfs_store(struct ufs_hba *hba,
+        const char *buf, size_t count)
+{
+    char *strbuf;
+    char *strbuf_copy;
+    u8 desc_buf[QUERY_DESC_CONFIGURATION_DEF_SIZE] = {0};
+    int desc_buf_len = QUERY_DESC_CONFIGURATION_DEF_SIZE;
+    char *token;
+    int i, ret, value;
+    u32 config_desc_lock = 0;
+
+    /* reserve one byte for null termination */
+    strbuf = kmalloc(count + 1, GFP_KERNEL);
+    if (!strbuf)
+        return -ENOMEM;
+
+    strbuf_copy = strbuf;
+    strlcpy(strbuf, buf, count + 1);
+
+    /* Just return if bConfigDescrLock is already set */
+    ret = ufshcd_query_attr(hba, UPIU_QUERY_OPCODE_READ_ATTR,
+        QUERY_ATTR_IDN_CONF_DESC_LOCK, 0, 0, &config_desc_lock);
+    if (ret)
+        goto out;
+
+    if (config_desc_lock) {
+        dev_err(hba->dev, "%s: bConfigDescrLock already set to %u,

cannot re-provision device!\n",
+        __func__, config_desc_lock);
+        ret = -EINVAL;
+        goto out;
+    }

drivers/scsi/ufs/ufs-configfs.c new file +18 -0

+
+    for (i = 0; i < QUERY_DESC_CONFIGURATION_DEF_SIZE; i++) {
+        token = strsep(&strbuf, " ");
+        if (!token && i)
+            break;
+
+        ret = kstrtoint(token, 0, &value);
+        if (ret) {
+            dev_err(hba->dev, "%s: kstrtoint failed %d %s\n",
+                __func__, ret, token);
+            ret = -EINVAL;
+            goto out;
+        }
+        desc_buf[i] = (u8)value;
+    }
+
+    /* Write configuration descriptor to provision ufs */
+    ret = ufshcd_query_descriptor_retry(hba,

Quoted 8 lines

Quoted 5 lines

UPIU_QUERY_OPCODE_WRITE_DESC,
+        QUERY_DESC_IDN_CONFIGURATION, 0, 0, desc_buf, &desc_buf_len); +
+    if (!ret)
+        dev_info(hba->dev, "%s: UFS Provisioning done, reboot now!\n",

That is not necessarily true - bConfDescContinue might have been used or bConfigDescrLock might need to be set.  Better just to say that configuration descriptor 0 was written.

Agree. Will update.

Quoted 45 lines

Quoted 45 lines

+        __func__);

drivers/scsi/ufs/ufs-configfs.c new file +44 -0

+
+out:
+    kfree(strbuf_copy);
+    if (ret)
+        return ret;
+    return count;
+}
+
+static ssize_t ufs_provision_store(struct config_item *item,
+        const char *buf, size_t count)
+{
+    struct ufs_hba *hba = config_item_to_hba(item);
+
+    return ufshcd_desc_configfs_store(hba, buf, count);
+}
+
+static struct configfs_attribute ufshcd_attr_provision = {
+    .ca_name    = "ufs_provision",
+    .ca_mode    = 0644,
+    .ca_owner    = THIS_MODULE,
+    .show        = ufs_provision_show,
+    .store        = ufs_provision_store,
+};
+
+static struct configfs_attribute *ufshcd_attrs[] = {
+    &ufshcd_attr_provision,
+    NULL,
+};
+
+static struct config_item_type ufscfg_type = {
+    .ct_attrs    = ufshcd_attrs,
+    .ct_owner    = THIS_MODULE,
+};
+
+static struct configfs_subsystem ufscfg_subsys = {
+    .su_group = {
+        .cg_item = {
+            .ci_type = &ufscfg_type,
+        },
+    },
+};
+
+void ufshcd_configfs_init(struct ufs_hba *hba, const char *name)
+{

Quoted 8 lines

Quoted 6 lines

+    int ret;
+    struct configfs_subsystem *subsys = &hba->subsys; +
+    strncpy(ufscfg_subsys.su_group.cg_item.ci_namebuf, name, strlen(name));
+    subsys->su_group = ufscfg_subsys.su_group;

configfs_subsystem cannot share su_group with other configfs_subsystem i.e you are not allowing for there being more than 1 hba

Agree. I think I will have to move above declarations(ufscfg_subsys/ufscfg_type/ufshcd_attrs) in driver .c/.h file (to make it per ufs hba/probe).
Will check and update.

Quoted 76 lines

Quoted 76 lines

+    config_group_init(&subsys->su_group);
+    mutex_init(&subsys->su_mutex);
+    ret = configfs_register_subsystem(subsys);
+    if (ret)
+        pr_err("Error %d while registering subsystem %s\n", +               ret,
+               subsys->su_group.cg_item.ci_namebuf);

drivers/scsi/ufs/ufs-configfs.c new file +6 -0

+}
+
+void ufshcd_configfs_exit(void)
+{
+    configfs_unregister_subsystem(&ufscfg_subsys);
+}

drivers/scsi/ufs/ufshcd.c +2 -1

index e01cdc0..32a67b0 100644
@@ -7711,6 +7711,7 @@ int ufshcd_shutdown(struct ufs_hba *hba)
    void ufshcd_remove(struct ufs_hba *hba)
    {
        ufs_sysfs_remove_nodes(hba->dev);
+    ufshcd_configfs_exit();
        scsi_remove_host(hba->host);
        /* disable interrupts */
        ufshcd_disable_intr(hba, hba->intr_mask);

@@ -7965,7 +7966,7 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem
 *mmio_base, unsigned int irq)
          async_schedule(ufshcd_async_scan, hba);
        ufs_sysfs_add_nodes(hba->dev);
-
+    ufshcd_configfs_init(hba, dev_name(hba->dev));
        return 0;
      out_remove_scsi_host:

drivers/scsi/ufs/ufshcd.h +3 -0

index 45013b6..2275032 100644
@@ -37,6 +37,7 @@
    #ifndef _UFSHCD_H
    #define _UFSHCD_H
    +#include <linux/configfs.h>
    #include <linux/module.h>
    #include <linux/kernel.h>
    #include <linux/init.h>

@@ -515,6 +516,9 @@ struct ufs_hba {
          struct Scsi_Host *host;
        struct device *dev;
+#ifdef CONFIG_UFS_PROVISION
+    struct configfs_subsystem subsys;
+#endif
        /*
         * This field is to keep a reference to "scsi_device"

corresponding to
        * "UFS device" W-LU.

drivers/scsi/ufs/ufshcd.h +12 -0

@@ -868,6 +872,19 @@ int ufshcd_read_string_desc(struct ufs_hba *hba, int
 desc_index,
    int ufshcd_hold(struct ufs_hba *hba, bool async);
    void ufshcd_release(struct ufs_hba *hba);
    +/* Expose UFS configfs API's */
+#ifndef CONFIG_UFS_PROVISION
+static inline void ufshcd_configfs_init(struct ufs_hba *hba, const char
 *name)
+{
+}
+static inline void ufshcd_configfs_exit(void)
+{
+}
+#else
+void ufshcd_configfs_init(struct ufs_hba *hba, const char *name);
+void ufshcd_configfs_exit(void);
+#endif
+
    int ufshcd_map_desc_id_to_length(struct ufs_hba *hba, enum desc_idn

desc_id,
       int *desc_length);