[PATCH v2] scsi: ufs: sysfs: Print string descriptors as raw data

[Arthur Simchaev <Arthur.Simchaev@wdc.com>]

Currently the string descriptors sysfs entries are printing in ascii
format. According to Jedec UFS spec the string descriptors data is
Unicode and need-not be ascii convertible. Therefore in case the device
string descriptor contains non ascii convertible characters, it will
produce a wrong output. In order to fix this issue, the new
string descriptors entries will added to sysfs directory.
Those entries will show the string descriptors in raw format

Signed-off-by: Arthur Simchaev <Arthur.Simchaev@wdc.com>
---
 Documentation/ABI/testing/sysfs-driver-ufs | 44 ++++++++++++++++++++++++++++++
 drivers/scsi/ufs/ufs-sysfs.c               | 34 +++++++++++++++++------
 2 files changed, 70 insertions(+), 8 deletions(-)

diff --git a/Documentation/ABI/testing/sysfs-driver-ufs b/Documentation/ABI/testing/sysfs-driver-ufs
index d1bc23c..f6d6a46 100644
--- a/Documentation/ABI/testing/sysfs-driver-ufs
+++ b/Documentation/ABI/testing/sysfs-driver-ufs
@@ -561,6 +561,50 @@ Description:	This file contains a product revision string. The full
 
 		The file is read only.
 
+What:		/sys/bus/platform/drivers/ufshcd/*/string_descriptors/manufacturer_name_raw
+Date:		February 2021
+Contact:	Arthur Simchaev <arthur.simchaev@wdc.com>
+Description:	This file contains a device manufactureer name string
+		as raw data. The full information about the descriptor
+		could be found at UFS specifications 2.1.
+
+		The file is read only.
+
+What:		/sys/bus/platform/drivers/ufshcd/*/string_descriptors/product_name_raw
+Date:		February 2021
+Contact:	Arthur Simchaev <arthur.simchaev@wdc.com>
+Description:	This file contains a product name string as raw data.
+		The full information about the descriptor could be found at
+		UFS specifications 2.1.
+
+		The file is read only.
+
+What:		/sys/bus/platform/drivers/ufshcd/*/string_descriptors/oem_id_raw
+Date:		February 2021
+Contact:	Arthur Simchaev <arthur.simchaev@wdc.com>
+Description:	This file contains a OEM ID string as raw data.
+		The full information about the descriptor could be found at
+		UFS specifications 2.1.
+
+		The file is read only.
+
+What:		/sys/bus/platform/drivers/ufshcd/*/string_descriptors/serial_number_raw
+Date:		February 2021
+Contact:	Arthur Simchaev <arthur.simchaev@wdc.com>
+Description:	This file contains a device serial number string
+		as raw data. The full information about the descriptor could be
+		found at UFS specifications 2.1.
+
+		The file is read only.
+
+What:		/sys/bus/platform/drivers/ufshcd/*/string_descriptors/product_revision_raw
+Date:		February 2021
+Contact:	Arthur Simchaev <arthur.simchaev@wdc.com>
+Description:	This file contains a product revision string as raw data.
+		The full information about the descriptor could be found at
+		UFS specifications 2.1.
+
+		The file is read only.
 
 What:		/sys/class/scsi_device/*/device/unit_descriptor/boot_lun_id
 Date:		February 2018
diff --git a/drivers/scsi/ufs/ufs-sysfs.c b/drivers/scsi/ufs/ufs-sysfs.c
index acc54f5..f1407ff 100644
--- a/drivers/scsi/ufs/ufs-sysfs.c
+++ b/drivers/scsi/ufs/ufs-sysfs.c
@@ -658,7 +658,7 @@ static const struct attribute_group ufs_sysfs_power_descriptor_group = {
 	.attrs = ufs_sysfs_power_descriptor,
 };
 
-#define UFS_STRING_DESCRIPTOR(_name, _pname)				\
+#define UFS_STRING_DESCRIPTOR(_name, _pname, _is_ascii)		\
 static ssize_t _name##_show(struct device *dev,				\
 	struct device_attribute *attr, char *buf)			\
 {									\
@@ -690,10 +690,18 @@ static ssize_t _name##_show(struct device *dev,				\
 	kfree(desc_buf);						\
 	desc_buf = NULL;						\
 	ret = ufshcd_read_string_desc(hba, index, &desc_buf,		\
-				      SD_ASCII_STD);			\
+				      _is_ascii);			\
 	if (ret < 0)							\
 		goto out;						\
-	ret = sysfs_emit(buf, "%s\n", desc_buf);			\
+	if (_is_ascii) {						\
+		ret = sysfs_emit(buf, "%s\n", desc_buf);		\
+	} else {							\
+		int i;							\
+									\
+		for (i = 0; i < desc_buf[0]; i++)			\
+			hex_byte_pack(buf + i * 2, desc_buf[i]);	\
+		ret = sysfs_emit(buf, "%s\n", buf);			\
+	}			\
 out:									\
 	pm_runtime_put_sync(hba->dev);					\
 	kfree(desc_buf);						\
@@ -702,11 +710,16 @@ out:									\
 }									\
 static DEVICE_ATTR_RO(_name)
 
-UFS_STRING_DESCRIPTOR(manufacturer_name, _MANF_NAME);
-UFS_STRING_DESCRIPTOR(product_name, _PRDCT_NAME);
-UFS_STRING_DESCRIPTOR(oem_id, _OEM_ID);
-UFS_STRING_DESCRIPTOR(serial_number, _SN);
-UFS_STRING_DESCRIPTOR(product_revision, _PRDCT_REV);
+UFS_STRING_DESCRIPTOR(manufacturer_name, _MANF_NAME, 1);
+UFS_STRING_DESCRIPTOR(product_name, _PRDCT_NAME, 1);
+UFS_STRING_DESCRIPTOR(oem_id, _OEM_ID, 1);
+UFS_STRING_DESCRIPTOR(serial_number, _SN, 1);
+UFS_STRING_DESCRIPTOR(product_revision, _PRDCT_REV, 1);
+UFS_STRING_DESCRIPTOR(manufacturer_name_raw, _MANF_NAME, 0);
+UFS_STRING_DESCRIPTOR(product_name_raw, _PRDCT_NAME, 0);
+UFS_STRING_DESCRIPTOR(oem_id_raw, _OEM_ID, 0);
+UFS_STRING_DESCRIPTOR(serial_number_raw, _SN, 0);
+UFS_STRING_DESCRIPTOR(product_revision_raw, _PRDCT_REV, 0);
 
 static struct attribute *ufs_sysfs_string_descriptors[] = {
 	&dev_attr_manufacturer_name.attr,
@@ -714,6 +727,11 @@ static struct attribute *ufs_sysfs_string_descriptors[] = {
 	&dev_attr_oem_id.attr,
 	&dev_attr_serial_number.attr,
 	&dev_attr_product_revision.attr,
+	&dev_attr_manufacturer_name_raw.attr,
+	&dev_attr_product_name_raw.attr,
+	&dev_attr_oem_id_raw.attr,
+	&dev_attr_serial_number_raw.attr,
+	&dev_attr_product_revision_raw.attr,
 	NULL,
 };
 
-- 
2.7.4