linux-zen-server/drivers/net/can/usb/etas_es58x/es58x_devlink.c

236 lines
7.0 KiB
C

// SPDX-License-Identifier: GPL-2.0
/* Driver for ETAS GmbH ES58X USB CAN(-FD) Bus Interfaces.
*
* File es58x_devlink.c: report the product information using devlink.
*
* Copyright (c) 2022 Vincent Mailhol <mailhol.vincent@wanadoo.fr>
*/
#include <linux/ctype.h>
#include <linux/device.h>
#include <linux/usb.h>
#include <net/devlink.h>
#include "es58x_core.h"
/* USB descriptor index containing the product information string. */
#define ES58X_PROD_INFO_IDX 6
/**
* es58x_parse_sw_version() - Extract boot loader or firmware version.
* @es58x_dev: ES58X device.
* @prod_info: USB custom string returned by the device.
* @prefix: Select which information should be parsed. Set it to "FW"
* to parse the firmware version or to "BL" to parse the
* bootloader version.
*
* The @prod_info string contains the firmware and the bootloader
* version number all prefixed by a magic string and concatenated with
* other numbers. Depending on the device, the firmware (bootloader)
* format is either "FW_Vxx.xx.xx" ("BL_Vxx.xx.xx") or "FW:xx.xx.xx"
* ("BL:xx.xx.xx") where 'x' represents a digit. @prod_info must
* contains the common part of those prefixes: "FW" or "BL".
*
* Parse @prod_info and store the version number in
* &es58x_dev.firmware_version or &es58x_dev.bootloader_version
* according to @prefix value.
*
* Return: zero on success, -EINVAL if @prefix contains an invalid
* value and -EBADMSG if @prod_info could not be parsed.
*/
static int es58x_parse_sw_version(struct es58x_device *es58x_dev,
const char *prod_info, const char *prefix)
{
struct es58x_sw_version *version;
int major, minor, revision;
if (!strcmp(prefix, "FW"))
version = &es58x_dev->firmware_version;
else if (!strcmp(prefix, "BL"))
version = &es58x_dev->bootloader_version;
else
return -EINVAL;
/* Go to prefix */
prod_info = strstr(prod_info, prefix);
if (!prod_info)
return -EBADMSG;
/* Go to beginning of the version number */
while (!isdigit(*prod_info)) {
prod_info++;
if (!*prod_info)
return -EBADMSG;
}
if (sscanf(prod_info, "%2u.%2u.%2u", &major, &minor, &revision) != 3)
return -EBADMSG;
version->major = major;
version->minor = minor;
version->revision = revision;
return 0;
}
/**
* es58x_parse_hw_rev() - Extract hardware revision number.
* @es58x_dev: ES58X device.
* @prod_info: USB custom string returned by the device.
*
* @prod_info contains the hardware revision prefixed by a magic
* string and conquenated together with other numbers. Depending on
* the device, the hardware revision format is either
* "HW_VER:axxx/xxx" or "HR:axxx/xxx" where 'a' represents a letter
* and 'x' a digit.
*
* Parse @prod_info and store the hardware revision number in
* &es58x_dev.hardware_revision.
*
* Return: zero on success, -EBADMSG if @prod_info could not be
* parsed.
*/
static int es58x_parse_hw_rev(struct es58x_device *es58x_dev,
const char *prod_info)
{
char letter;
int major, minor;
/* The only occurrence of 'H' is in the hardware revision prefix. */
prod_info = strchr(prod_info, 'H');
if (!prod_info)
return -EBADMSG;
/* Go to beginning of the hardware revision */
prod_info = strchr(prod_info, ':');
if (!prod_info)
return -EBADMSG;
prod_info++;
if (sscanf(prod_info, "%c%3u/%3u", &letter, &major, &minor) != 3)
return -EBADMSG;
es58x_dev->hardware_revision.letter = letter;
es58x_dev->hardware_revision.major = major;
es58x_dev->hardware_revision.minor = minor;
return 0;
}
/**
* es58x_parse_product_info() - Parse the ES58x product information
* string.
* @es58x_dev: ES58X device.
*
* Retrieve the product information string and parse it to extract the
* firmware version, the bootloader version and the hardware
* revision.
*
* If the function fails, simply emit a log message and continue
* because product information is not critical for the driver to
* operate.
*/
void es58x_parse_product_info(struct es58x_device *es58x_dev)
{
char *prod_info;
prod_info = usb_cache_string(es58x_dev->udev, ES58X_PROD_INFO_IDX);
if (!prod_info) {
dev_warn(es58x_dev->dev,
"could not retrieve the product info string\n");
return;
}
if (es58x_parse_sw_version(es58x_dev, prod_info, "FW") ||
es58x_parse_sw_version(es58x_dev, prod_info, "BL") ||
es58x_parse_hw_rev(es58x_dev, prod_info))
dev_info(es58x_dev->dev,
"could not parse product info: '%s'\n", prod_info);
kfree(prod_info);
}
/**
* es58x_sw_version_is_set() - Check if the version is a valid number.
* @sw_ver: Version number of either the firmware or the bootloader.
*
* If &es58x_sw_version.major, &es58x_sw_version.minor and
* &es58x_sw_version.revision are all zero, the product string could
* not be parsed and the version number is invalid.
*/
static inline bool es58x_sw_version_is_set(struct es58x_sw_version *sw_ver)
{
return sw_ver->major || sw_ver->minor || sw_ver->revision;
}
/**
* es58x_hw_revision_is_set() - Check if the revision is a valid number.
* @hw_rev: Revision number of the hardware.
*
* If &es58x_hw_revision.letter is the null character, the product
* string could not be parsed and the hardware revision number is
* invalid.
*/
static inline bool es58x_hw_revision_is_set(struct es58x_hw_revision *hw_rev)
{
return hw_rev->letter != '\0';
}
/**
* es58x_devlink_info_get() - Report the product information.
* @devlink: Devlink.
* @req: skb wrapper where to put requested information.
* @extack: Unused.
*
* Report the firmware version, the bootloader version, the hardware
* revision and the serial number through netlink.
*
* Return: zero on success, errno when any error occurs.
*/
static int es58x_devlink_info_get(struct devlink *devlink,
struct devlink_info_req *req,
struct netlink_ext_ack *extack)
{
struct es58x_device *es58x_dev = devlink_priv(devlink);
struct es58x_sw_version *fw_ver = &es58x_dev->firmware_version;
struct es58x_sw_version *bl_ver = &es58x_dev->bootloader_version;
struct es58x_hw_revision *hw_rev = &es58x_dev->hardware_revision;
char buf[max(sizeof("xx.xx.xx"), sizeof("axxx/xxx"))];
int ret = 0;
if (es58x_sw_version_is_set(fw_ver)) {
snprintf(buf, sizeof(buf), "%02u.%02u.%02u",
fw_ver->major, fw_ver->minor, fw_ver->revision);
ret = devlink_info_version_running_put(req,
DEVLINK_INFO_VERSION_GENERIC_FW,
buf);
if (ret)
return ret;
}
if (es58x_sw_version_is_set(bl_ver)) {
snprintf(buf, sizeof(buf), "%02u.%02u.%02u",
bl_ver->major, bl_ver->minor, bl_ver->revision);
ret = devlink_info_version_running_put(req,
DEVLINK_INFO_VERSION_GENERIC_FW_BOOTLOADER,
buf);
if (ret)
return ret;
}
if (es58x_hw_revision_is_set(hw_rev)) {
snprintf(buf, sizeof(buf), "%c%03u/%03u",
hw_rev->letter, hw_rev->major, hw_rev->minor);
ret = devlink_info_version_fixed_put(req,
DEVLINK_INFO_VERSION_GENERIC_BOARD_REV,
buf);
if (ret)
return ret;
}
return devlink_info_serial_number_put(req, es58x_dev->udev->serial);
}
const struct devlink_ops es58x_dl_ops = {
.info_get = es58x_devlink_info_get,
};