iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

mtd: spi-nor: add initial sysfs support

Browse Source 
Add support to show the manufacturer, the partname and JEDEC identifier
as well as to dump the SFDP table. Not all flashes list their SFDP table
contents in their datasheet. So having that is useful. It might also be
helpful in bug reports from users.

Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Acked-by: Pratyush Yadav <p.yadav@ti.com>
This commit is contained in:
Michael Walle 2021-05-03 17:56:51 +02:00 committed by Vignesh Raghavendra
parent 65b6d89d45
commit 36ac022862
5 changed files with 128 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

31
Documentation/ABI/testing/sysfs-bus-spi-devices-spi-nor Normal file
View File

@ -0,0 +1,31 @@
What: /sys/bus/spi/devices/.../spi-nor/jedec_id
Date: April 2021
KernelVersion: 5.14
Contact: linux-mtd@lists.infradead.org
Description: (RO) The JEDEC ID of the SPI NOR flash as reported by the
flash device.
What: /sys/bus/spi/devices/.../spi-nor/manufacturer
Date: April 2021
KernelVersion: 5.14
Contact: linux-mtd@lists.infradead.org
Description: (RO) Manufacturer of the SPI NOR flash.
What: /sys/bus/spi/devices/.../spi-nor/partname
Date: April 2021
KernelVersion: 5.14
Contact: linux-mtd@lists.infradead.org
Description: (RO) Part name of the SPI NOR flash.
What: /sys/bus/spi/devices/.../spi-nor/sfdp
Date: April 2021
KernelVersion: 5.14
Contact: linux-mtd@lists.infradead.org
Description: (RO) This attribute is only present if the SPI NOR flash
device supports the "Read SFDP" command (5Ah).
If present, it contains the complete SFDP (serial flash
discoverable parameters) binary data of the flash.

2
drivers/mtd/spi-nor/Makefile
View File

@ -1,6 +1,6 @@
# SPDX-License-Identifier: GPL-2.0
spi-nor-objs := core.o sfdp.o swp.o otp.o
spi-nor-objs := core.o sfdp.o swp.o otp.o sysfs.o
spi-nor-objs += atmel.o
spi-nor-objs += catalyst.o
spi-nor-objs += eon.o

1
drivers/mtd/spi-nor/core.c
View File

@ -3459,6 +3459,7 @@ static struct spi_mem_driver spi_nor_driver = {
.driver = {
.name = "spi-nor",
.of_match_table = spi_nor_of_table,
.dev_groups = spi_nor_sysfs_groups,
},
.id_table = spi_nor_dev_ids,
},

2
drivers/mtd/spi-nor/core.h
View File

@ -490,6 +490,8 @@ extern const struct spi_nor_manufacturer spi_nor_winbond;
extern const struct spi_nor_manufacturer spi_nor_xilinx;
extern const struct spi_nor_manufacturer spi_nor_xmc;
extern const struct attribute_group *spi_nor_sysfs_groups[];
void spi_nor_spimem_setup_op(const struct spi_nor *nor,
struct spi_mem_op *op,
const enum spi_nor_protocol proto);

93
drivers/mtd/spi-nor/sysfs.c Normal file
View File

@ -0,0 +1,93 @@
// SPDX-License-Identifier: GPL-2.0
#include <linux/mtd/spi-nor.h>
#include <linux/spi/spi.h>
#include <linux/spi/spi-mem.h>
#include <linux/sysfs.h>
#include "core.h"
static ssize_t manufacturer_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct spi_device *spi = to_spi_device(dev);
struct spi_mem *spimem = spi_get_drvdata(spi);
struct spi_nor *nor = spi_mem_get_drvdata(spimem);
return sysfs_emit(buf, "%s\n", nor->manufacturer->name);
}
static DEVICE_ATTR_RO(manufacturer);
static ssize_t partname_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct spi_device *spi = to_spi_device(dev);
struct spi_mem *spimem = spi_get_drvdata(spi);
struct spi_nor *nor = spi_mem_get_drvdata(spimem);
return sysfs_emit(buf, "%s\n", nor->info->name);
}
static DEVICE_ATTR_RO(partname);
static ssize_t jedec_id_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct spi_device *spi = to_spi_device(dev);
struct spi_mem *spimem = spi_get_drvdata(spi);
struct spi_nor *nor = spi_mem_get_drvdata(spimem);
return sysfs_emit(buf, "%*phN\n", nor->info->id_len, nor->info->id);
}
static DEVICE_ATTR_RO(jedec_id);
static struct attribute *spi_nor_sysfs_entries[] = {
&dev_attr_manufacturer.attr,
&dev_attr_partname.attr,
&dev_attr_jedec_id.attr,
NULL
};
static ssize_t sfdp_read(struct file *filp, struct kobject *kobj,
struct bin_attribute *bin_attr, char *buf,
loff_t off, size_t count)
{
struct spi_device *spi = to_spi_device(kobj_to_dev(kobj));
struct spi_mem *spimem = spi_get_drvdata(spi);
struct spi_nor *nor = spi_mem_get_drvdata(spimem);
struct sfdp *sfdp = nor->sfdp;
size_t sfdp_size = sfdp->num_dwords * sizeof(*sfdp->dwords);
return memory_read_from_buffer(buf, count, &off, nor->sfdp->dwords,
sfdp_size);
}
static BIN_ATTR_RO(sfdp, 0);
static struct bin_attribute *spi_nor_sysfs_bin_entries[] = {
&bin_attr_sfdp,
NULL
};
static umode_t spi_nor_sysfs_is_bin_visible(struct kobject *kobj,
struct bin_attribute *attr, int n)
{
struct spi_device *spi = to_spi_device(kobj_to_dev(kobj));
struct spi_mem *spimem = spi_get_drvdata(spi);
struct spi_nor *nor = spi_mem_get_drvdata(spimem);
if (attr == &bin_attr_sfdp && nor->sfdp)
return 0444;
return 0;
}
static const struct attribute_group spi_nor_sysfs_group = {
.name = "spi-nor",
.is_bin_visible = spi_nor_sysfs_is_bin_visible,
.attrs = spi_nor_sysfs_entries,
.bin_attrs = spi_nor_sysfs_bin_entries,
};
const struct attribute_group *spi_nor_sysfs_groups[] = {
&spi_nor_sysfs_group,
NULL
};