Re: [PATCH] hwmon: pmbus: Add Inspur Power System power supply driver

From: Guenter Roeck
Date: Thu Aug 08 2019 - 10:05:30 EST

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In reply to: John Wang: "[PATCH] hwmon: pmbus: Add Inspur Power System power supply driver"
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On Thu, Aug 08, 2019 at 03:36:36PM +0800, John Wang wrote:
> Add the driver to monitor Inspur Power System power supplies
> with hwmon over pmbus.
>
> This driver adds debugfs entries for addintional power supply data,

s/addintional/additional/

> including vendor,model,part_number,serial number,firmware revision,
> hardware revision,and psu mode(active/standby).

Spaces after "'", please.

>

Please run checkpatch --strict and fix what it reports.
Mostly multi-line alignment, but also stray empty lines
and missing spaces.

> Signed-off-by: John Wang <wangzqbj@xxxxxxxxxx>
> ---
> drivers/hwmon/pmbus/Kconfig | 9 +
> drivers/hwmon/pmbus/Makefile | 1 +
> drivers/hwmon/pmbus/inspur-ipsps.c | 291 +++++++++++++++++++++++++++++
> 3 files changed, 301 insertions(+)
> create mode 100644 drivers/hwmon/pmbus/inspur-ipsps.c
>
> diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig
> index 30751eb9550a..c09357c26b10 100644
> --- a/drivers/hwmon/pmbus/Kconfig
> +++ b/drivers/hwmon/pmbus/Kconfig
> @@ -203,4 +203,13 @@ config SENSORS_ZL6100
> This driver can also be built as a module. If so, the module will
> be called zl6100.
>
> +config SENSORS_INSPUR_IPSPS
> + tristate "INSPUR Power System Power Supply"
> + help
> + If you say yes here you get hardware monitoring support for the INSPUR
> + Power System power supply.
> +
> + This driver can also be built as a module. If so, the module will
> + be called inspur-ipsps.
> +
> endif # PMBUS
> diff --git a/drivers/hwmon/pmbus/Makefile b/drivers/hwmon/pmbus/Makefile
> index 2219b9300316..fde2d10cd05c 100644
> --- a/drivers/hwmon/pmbus/Makefile
> +++ b/drivers/hwmon/pmbus/Makefile
> @@ -23,3 +23,4 @@ obj-$(CONFIG_SENSORS_TPS53679) += tps53679.o
> obj-$(CONFIG_SENSORS_UCD9000) += ucd9000.o
> obj-$(CONFIG_SENSORS_UCD9200) += ucd9200.o
> obj-$(CONFIG_SENSORS_ZL6100) += zl6100.o
> +obj-$(CONFIG_SENSORS_INSPUR_IPSPS) += inspur-ipsps.o
> diff --git a/drivers/hwmon/pmbus/inspur-ipsps.c b/drivers/hwmon/pmbus/inspur-ipsps.c
> new file mode 100644
> index 000000000000..7dc2b00cb192
> --- /dev/null
> +++ b/drivers/hwmon/pmbus/inspur-ipsps.c
> @@ -0,0 +1,291 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Copyright 2019 Inspur Corp.
> + */
> +
> +#include <linux/bitops.h>
> +#include <linux/debugfs.h>
> +#include <linux/device.h>
> +#include <linux/fs.h>
> +#include <linux/i2c.h>
> +#include <linux/module.h>
> +#include <linux/pmbus.h>
> +
> +#include "pmbus.h"
> +
> +#define IPSPS_VENDOR_ID 0x99
> +#define IPSPS_MODEL 0x9A
> +#define IPSPS_FW_VERSION 0x9B
> +#define IPSPS_PN 0x9C
> +#define IPSPS_SN 0x9E
> +#define IPSPS_HW_VERSION 0xB0
> +#define IPSPS_MODE 0xFC
> +
> +#define MODE_ACTIVE 0x55
> +#define MODE_STANDBY 0x0E
> +#define MODE_REDUNDANCY 0x00
> +
> +#define MODE_ACTIVE_STRING "active"
> +#define MODE_STANDBY_STRING "standby"
> +#define MODE_REDUNDANCY_STRING "redundancy"
> +
> +struct ipsps_attr {
> + u8 reg;
> + umode_t mode;
> + const char *name;
> + int mask;
> + const struct file_operations *fops;
> +};
> +
> +struct ipsps_entry {
> + struct i2c_client *client;
> + u8 reg;
> +};
> +
> +static ssize_t ipsps_string_read(struct file *file, char __user *buf,
> + size_t count, loff_t *ppos)
> +{
> + struct ipsps_entry *entry = file->private_data;
> + char data[I2C_SMBUS_BLOCK_MAX + 1] = { 0 };
> + int i, rc;
> +
> + rc = i2c_smbus_read_block_data(entry->client, entry->reg, data);
> + if (rc <= 0)
> + return rc;

With this, an read size of 0 returns nothing (no newline)
and no error. Anything else returns a string with newline.
Is that intentional ?

> +
> + for (i = 0; i < rc; i++) {
> + if (data[i] == '#')
> + break;

What if there is a '\0' in the buffer ?

> + }
> +
> + data[i] = '\n';
> + i++;

data[i++] = '\n';

> + data[i] = '\0';
> + i++;

data[i++] = '0';

i2c_smbus_read_block_data() can return up to 32 bytes of data.
If it does, and the code does not include a '#', the above writes
after the end of the bufer.

> +
> + return simple_read_from_buffer(buf, count, ppos, data, i);
> +
> +}
> +
> +static ssize_t ipsps_fw_version_read(struct file *file, char __user *buf,
> + size_t count, loff_t *ppos)
> +{
> + char data[I2C_SMBUS_BLOCK_MAX] = { 0 };
> + int rc;
> + struct ipsps_entry *entry = file->private_data;
> +
> + rc = i2c_smbus_read_block_data(entry->client, entry->reg, data);
> + if (rc < 0)
> + return rc;
> +
> + if (rc != 6)
> + return -ENODATA;

That seems inappropriate. There is data, after all, only it is unexpected.
-EPROTO, maybe.

> +
> + rc = snprintf(data, sizeof(data), "%d.%02d.%02d\n",
> + data[1], data[2], data[3]);

This will be reported as negative numbers if values are larger than 127.
Is this intentional ?

> +
> + return simple_read_from_buffer(buf, count, ppos, data, rc);
> +}
> +
> +static ssize_t ipsps_mode_read(struct file *file,
> + char __user *buf, size_t count,
> + loff_t *ppos)
> +{
> + int rc;
> + char data[64] = { 0 };
> + struct ipsps_entry *entry = file->private_data;

Please use reverse chrismas tree declarations where possible.

> +
> + rc = i2c_smbus_read_byte_data(entry->client, entry->reg);
> + if (rc < 0)
> + return rc;
> +
> + switch (rc) {
> + case MODE_ACTIVE:
> + rc = snprintf(data, sizeof(data), "[%s] %s %s\n",
> + MODE_ACTIVE_STRING,
> + MODE_STANDBY_STRING, MODE_REDUNDANCY_STRING);
> + break;
> + case MODE_STANDBY:
> + rc = snprintf(data, sizeof(data), "%s [%s] %s\n",
> + MODE_ACTIVE_STRING,
> + MODE_STANDBY_STRING, MODE_REDUNDANCY_STRING);
> + break;
> + case MODE_REDUNDANCY:
> + rc = snprintf(data, sizeof(data), "%s %s [%s]\n",
> + MODE_ACTIVE_STRING,
> + MODE_STANDBY_STRING, MODE_REDUNDANCY_STRING);
> + break;
> + default:
> + rc = snprintf(data, sizeof(data), "unspecified\n");
> + break;
> + }
> +
> + return simple_read_from_buffer(buf, count, ppos, data, rc);
> +}
> +
> +static ssize_t ipsps_mode_write(struct file *file, const char __user *buf,
> + size_t count, loff_t *ppos)
> +{
> + int rc;
> + char data[64] = { 0 };
> + struct ipsps_entry *entry = file->private_data;
> +
> + rc = simple_write_to_buffer(data, sizeof(data), ppos, buf, count);
> + if (rc < 0)
> + return rc;
> +
> + if (strcmp(MODE_STANDBY_STRING, data) == 0 ||
> + strcmp(MODE_STANDBY_STRING"\n", data) == 0) {

Any reason for not using sysfs_streq() ?

> + rc = i2c_smbus_write_byte_data(entry->client, entry->reg,
> + MODE_STANDBY);
> + if (rc < 0)
> + return rc;
> + return count;
> + } else if (strcmp(MODE_ACTIVE_STRING, data) == 0 ||
> + strcmp(MODE_ACTIVE_STRING"\n", data) == 0) {
> + rc = i2c_smbus_write_byte_data(entry->client, entry->reg,
> + MODE_ACTIVE);
> + if (rc < 0)
> + return rc;
> + return count;
> + }

So one can only set active and standby, but not "redundancy".
If that is intentional, it might make sense to document it somewhere.

Also, it is kind of unusual to configure a device with a debugfs entry.
Are you sure this is what you want, and not a sysfs attribute ?

> +
> + return -EINVAL;
> +}
> +
> +static const struct file_operations ipsps_string_fops = {
> + .llseek = noop_llseek,
> + .open = simple_open,
> + .read = ipsps_string_read,
> +};
> +
> +static const struct file_operations ipsps_fw_version_fops = {
> + .llseek = noop_llseek,
> + .open = simple_open,
> + .read = ipsps_fw_version_read,
> +};
> +
> +static const struct file_operations ipsps_mode_fops = {
> + .llseek = noop_llseek,
> + .open = simple_open,
> + .read = ipsps_mode_read,
> + .write = ipsps_mode_write,
> +};
> +
> +struct ipsps_attr ipsps_attrs[] = {
> + {
> + .name = "vendor",
> + .fops = &ipsps_string_fops,
> + .reg = IPSPS_VENDOR_ID,
> + .mode = 0444,
> + }, {
> + .name = "model",
> + .fops = &ipsps_string_fops,
> + .reg = IPSPS_MODEL,
> + .mode = 0444,
> + }, {
> + .name = "fw_version",
> + .fops = &ipsps_fw_version_fops,
> + .reg = IPSPS_FW_VERSION,
> + .mode = 0444,
> + }, {
> + .name = "part_number",
> + .fops = &ipsps_string_fops,
> + .reg = IPSPS_PN,
> + .mode = 0444,
> + }, {
> + .name = "serial_number",
> + .fops = &ipsps_string_fops,
> + .reg = IPSPS_SN,
> + .mode = 0444,
> + }, {
> + .name = "hw_version",
> + .fops = &ipsps_string_fops,
> + .reg = IPSPS_HW_VERSION,
> + .mode = 0444,
> + }, {
> + .name = "mode",
> + .fops = &ipsps_mode_fops,
> + .reg = IPSPS_MODE,
> + .mode = 0644,
> + }
> +
> +};
> +
> +static struct pmbus_driver_info ipsps_info = {
> + .pages = 1,
> + .func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT |
> + PMBUS_HAVE_POUT | PMBUS_HAVE_PIN | PMBUS_HAVE_FAN12 |
> + PMBUS_HAVE_TEMP | PMBUS_HAVE_TEMP2 | PMBUS_HAVE_TEMP3 |
> + PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT |
> + PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP |
> + PMBUS_HAVE_STATUS_FAN12,
> +};
> +
> +static struct pmbus_platform_data ipsps_pdata = {
> + .flags = PMBUS_SKIP_STATUS_CHECK,
> +};
> +
> +static int ipsps_probe(struct i2c_client *client,
> + const struct i2c_device_id *id)
> +{
> + int i, rc;
> + struct dentry *debugfs;
> + struct dentry *ipsps_dir;
> + struct ipsps_entry *entry;
> +
> + client->dev.platform_data = &ipsps_pdata;
> + rc = pmbus_do_probe(client, id, &ipsps_info);
> + if (rc)
> + return rc;
> +
> + /* Don't fail the probe if we can't create debugfs */
> + debugfs = pmbus_get_debugfs_dir(client);
> + if (!debugfs)
> + return 0;
> +
> + ipsps_dir = debugfs_create_dir(client->name, debugfs);
> + if (!ipsps_dir)
> + return 0;
> +
> + for (i = 0; i < ARRAY_SIZE(ipsps_attrs); ++i) {
> + entry = devm_kzalloc(&client->dev, sizeof(*entry), GFP_KERNEL);
> + if (!entry)
> + return 0;
> +
> + entry->client = client;
> + entry->reg = ipsps_attrs[i].reg;
> + debugfs_create_file(ipsps_attrs[i].name, ipsps_attrs[i].mode,
> + ipsps_dir, entry, ipsps_attrs[i].fops);
> + }
> +
> + return 0;
> +}
> +
> +static const struct i2c_device_id ipsps_id[] = {
> + { "inspur_ipsps1", 1 },

What is the "1" for ? It isn't used, so 0 might be more appropriate.

> + {}
> +};
> +MODULE_DEVICE_TABLE(i2c, ipsps_id);
> +
> +static const struct of_device_id ipsps_of_match[] = {
> + { .compatible = "inspur,ipsps1" },

Please make sure this is documented in
./Documentation/devicetree/bindings/trivial-devices.yaml.

> + {}
> +};
> +MODULE_DEVICE_TABLE(of, ipsps_of_match);
> +
> +static struct i2c_driver ipsps_driver = {
> + .driver = {
> + .name = "inspur-ipsps",
> + .of_match_table = ipsps_of_match,
> + },
> + .probe = ipsps_probe,
> + .remove = pmbus_do_remove,
> + .id_table = ipsps_id,
> +};
> +
> +module_i2c_driver(ipsps_driver);
> +
> +MODULE_AUTHOR("John Wang");
> +MODULE_DESCRIPTION("PMBus driver for Inspur Power System power supplies");
> +MODULE_LICENSE("GPL");

Next message: Neil Armstrong: "Re: [PATCH 4/9] drm: meson: vpp: use proper macros instead of magic constants"
Previous message: Boris Brezillon: "Re: [PATCH v5 2/3] mtd: spi-nor: Move m25p80 code in spi-nor.c"
In reply to: John Wang: "[PATCH] hwmon: pmbus: Add Inspur Power System power supply driver"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]