// 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 */ #include #include #include #include #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, set the version or revision to an invalid * value and emit an informal message. Continue probing because the * product information is not critical for the driver to operate. */ void es58x_parse_product_info(struct es58x_device *es58x_dev) { static const struct es58x_sw_version sw_version_not_set = { .major = -1, .minor = -1, .revision = -1, }; static const struct es58x_hw_revision hw_revision_not_set = { .letter = '\0', .major = -1, .minor = -1, }; char *prod_info; es58x_dev->firmware_version = sw_version_not_set; es58x_dev->bootloader_version = sw_version_not_set; es58x_dev->hardware_revision = hw_revision_not_set; 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_valid() - Check if the version is a valid number. * @sw_ver: Version number of either the firmware or the bootloader. * * If any of the software version sub-numbers do not fit on two * digits, the version is invalid, most probably because the product * string could not be parsed. * * Return: @true if the software version is valid, @false otherwise. */ static inline bool es58x_sw_version_is_valid(struct es58x_sw_version *sw_ver) { return sw_ver->major < 100 && sw_ver->minor < 100 && sw_ver->revision < 100; } /** * es58x_hw_revision_is_valid() - Check if the revision is a valid number. * @hw_rev: Revision number of the hardware. * * If &es58x_hw_revision.letter is not a alphanumeric character or if * any of the hardware revision sub-numbers do not fit on three * digits, the revision is invalid, most probably because the product * string could not be parsed. * * Return: @true if the hardware revision is valid, @false otherwise. */ static inline bool es58x_hw_revision_is_valid(struct es58x_hw_revision *hw_rev) { return isalnum(hw_rev->letter) && hw_rev->major < 1000 && hw_rev->minor < 1000; } /** * 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_valid(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_valid(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_valid(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, };