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1// SPDX-License-Identifier: GPL-2.02/*3 * CZ.NIC's Turris Omnia MCU driver4 *5 * 2024 by Marek Behún <kabel@kernel.org>6 */7 8#include <linux/array_size.h>9#include <linux/bits.h>10#include <linux/device.h>11#include <linux/errno.h>12#include <linux/hex.h>13#include <linux/i2c.h>14#include <linux/module.h>15#include <linux/string.h>16#include <linux/sysfs.h>17#include <linux/types.h>18 19#include <linux/turris-omnia-mcu-interface.h>20#include "turris-omnia-mcu.h"21 22#define OMNIA_FW_VERSION_LEN 2023#define OMNIA_FW_VERSION_HEX_LEN (2 * OMNIA_FW_VERSION_LEN + 1)24#define OMNIA_BOARD_INFO_LEN 1625 26int omnia_cmd_write_read(const struct i2c_client *client,27 void *cmd, unsigned int cmd_len,28 void *reply, unsigned int reply_len)29{30 struct i2c_msg msgs[2];31 int ret, num;32 33 msgs[0].addr = client->addr;34 msgs[0].flags = 0;35 msgs[0].len = cmd_len;36 msgs[0].buf = cmd;37 num = 1;38 39 if (reply_len) {40 msgs[1].addr = client->addr;41 msgs[1].flags = I2C_M_RD;42 msgs[1].len = reply_len;43 msgs[1].buf = reply;44 num++;45 }46 47 ret = i2c_transfer(client->adapter, msgs, num);48 if (ret < 0)49 return ret;50 if (ret != num)51 return -EIO;52 53 return 0;54}55 56static int omnia_get_version_hash(struct omnia_mcu *mcu, bool bootloader,57 char version[static OMNIA_FW_VERSION_HEX_LEN])58{59 u8 reply[OMNIA_FW_VERSION_LEN];60 char *p;61 int err;62 63 err = omnia_cmd_read(mcu->client,64 bootloader ? OMNIA_CMD_GET_FW_VERSION_BOOT65 : OMNIA_CMD_GET_FW_VERSION_APP,66 reply, sizeof(reply));67 if (err)68 return err;69 70 p = bin2hex(version, reply, OMNIA_FW_VERSION_LEN);71 *p = '\0';72 73 return 0;74}75 76static ssize_t fw_version_hash_show(struct device *dev, char *buf,77 bool bootloader)78{79 struct omnia_mcu *mcu = dev_get_drvdata(dev);80 char version[OMNIA_FW_VERSION_HEX_LEN];81 int err;82 83 err = omnia_get_version_hash(mcu, bootloader, version);84 if (err)85 return err;86 87 return sysfs_emit(buf, "%s\n", version);88}89 90static ssize_t fw_version_hash_application_show(struct device *dev,91 struct device_attribute *a,92 char *buf)93{94 return fw_version_hash_show(dev, buf, false);95}96static DEVICE_ATTR_RO(fw_version_hash_application);97 98static ssize_t fw_version_hash_bootloader_show(struct device *dev,99 struct device_attribute *a,100 char *buf)101{102 return fw_version_hash_show(dev, buf, true);103}104static DEVICE_ATTR_RO(fw_version_hash_bootloader);105 106static ssize_t fw_features_show(struct device *dev, struct device_attribute *a,107 char *buf)108{109 struct omnia_mcu *mcu = dev_get_drvdata(dev);110 111 return sysfs_emit(buf, "0x%x\n", mcu->features);112}113static DEVICE_ATTR_RO(fw_features);114 115static ssize_t mcu_type_show(struct device *dev, struct device_attribute *a,116 char *buf)117{118 struct omnia_mcu *mcu = dev_get_drvdata(dev);119 120 return sysfs_emit(buf, "%s\n", mcu->type);121}122static DEVICE_ATTR_RO(mcu_type);123 124static ssize_t reset_selector_show(struct device *dev,125 struct device_attribute *a, char *buf)126{127 u8 reply;128 int err;129 130 err = omnia_cmd_read_u8(to_i2c_client(dev), OMNIA_CMD_GET_RESET,131 &reply);132 if (err)133 return err;134 135 return sysfs_emit(buf, "%d\n", reply);136}137static DEVICE_ATTR_RO(reset_selector);138 139static ssize_t serial_number_show(struct device *dev,140 struct device_attribute *a, char *buf)141{142 struct omnia_mcu *mcu = dev_get_drvdata(dev);143 144 return sysfs_emit(buf, "%016llX\n", mcu->board_serial_number);145}146static DEVICE_ATTR_RO(serial_number);147 148static ssize_t first_mac_address_show(struct device *dev,149 struct device_attribute *a, char *buf)150{151 struct omnia_mcu *mcu = dev_get_drvdata(dev);152 153 return sysfs_emit(buf, "%pM\n", mcu->board_first_mac);154}155static DEVICE_ATTR_RO(first_mac_address);156 157static ssize_t board_revision_show(struct device *dev,158 struct device_attribute *a, char *buf)159{160 struct omnia_mcu *mcu = dev_get_drvdata(dev);161 162 return sysfs_emit(buf, "%u\n", mcu->board_revision);163}164static DEVICE_ATTR_RO(board_revision);165 166static struct attribute *omnia_mcu_base_attrs[] = {167 &dev_attr_fw_version_hash_application.attr,168 &dev_attr_fw_version_hash_bootloader.attr,169 &dev_attr_fw_features.attr,170 &dev_attr_mcu_type.attr,171 &dev_attr_reset_selector.attr,172 &dev_attr_serial_number.attr,173 &dev_attr_first_mac_address.attr,174 &dev_attr_board_revision.attr,175 NULL176};177 178static umode_t omnia_mcu_base_attrs_visible(struct kobject *kobj,179 struct attribute *a, int n)180{181 struct device *dev = kobj_to_dev(kobj);182 struct omnia_mcu *mcu = dev_get_drvdata(dev);183 184 if ((a == &dev_attr_serial_number.attr ||185 a == &dev_attr_first_mac_address.attr ||186 a == &dev_attr_board_revision.attr) &&187 !(mcu->features & OMNIA_FEAT_BOARD_INFO))188 return 0;189 190 return a->mode;191}192 193static const struct attribute_group omnia_mcu_base_group = {194 .attrs = omnia_mcu_base_attrs,195 .is_visible = omnia_mcu_base_attrs_visible,196};197 198static const struct attribute_group *omnia_mcu_groups[] = {199 &omnia_mcu_base_group,200#ifdef CONFIG_TURRIS_OMNIA_MCU_GPIO201 &omnia_mcu_gpio_group,202#endif203#ifdef CONFIG_TURRIS_OMNIA_MCU_SYSOFF_WAKEUP204 &omnia_mcu_poweroff_group,205#endif206 NULL207};208 209static void omnia_mcu_print_version_hash(struct omnia_mcu *mcu, bool bootloader)210{211 const char *type = bootloader ? "bootloader" : "application";212 struct device *dev = &mcu->client->dev;213 char version[OMNIA_FW_VERSION_HEX_LEN];214 int err;215 216 err = omnia_get_version_hash(mcu, bootloader, version);217 if (err) {218 dev_err(dev, "Cannot read MCU %s firmware version: %d\n",219 type, err);220 return;221 }222 223 dev_info(dev, "MCU %s firmware version hash: %s\n", type, version);224}225 226static const char *omnia_status_to_mcu_type(u16 status)227{228 switch (status & OMNIA_STS_MCU_TYPE_MASK) {229 case OMNIA_STS_MCU_TYPE_STM32:230 return "STM32";231 case OMNIA_STS_MCU_TYPE_GD32:232 return "GD32";233 case OMNIA_STS_MCU_TYPE_MKL:234 return "MKL";235 default:236 return "unknown";237 }238}239 240static void omnia_info_missing_feature(struct device *dev, const char *feature)241{242 dev_info(dev,243 "Your board's MCU firmware does not support the %s feature.\n",244 feature);245}246 247static int omnia_mcu_read_features(struct omnia_mcu *mcu)248{249 static const struct {250 u16 mask;251 const char *name;252 } features[] = {253#define _DEF_FEAT(_n, _m) { OMNIA_FEAT_ ## _n, _m }254 _DEF_FEAT(EXT_CMDS, "extended control and status"),255 _DEF_FEAT(WDT_PING, "watchdog pinging"),256 _DEF_FEAT(LED_STATE_EXT_MASK, "peripheral LED pins reading"),257 _DEF_FEAT(NEW_INT_API, "new interrupt API"),258 _DEF_FEAT(POWEROFF_WAKEUP, "poweroff and wakeup"),259 _DEF_FEAT(TRNG, "true random number generator"),260#undef _DEF_FEAT261 };262 struct i2c_client *client = mcu->client;263 struct device *dev = &client->dev;264 bool suggest_fw_upgrade = false;265 u16 status;266 int err;267 268 /* status word holds MCU type, which we need below */269 err = omnia_cmd_read_u16(client, OMNIA_CMD_GET_STATUS_WORD, &status);270 if (err)271 return err;272 273 /*274 * Check whether MCU firmware supports the OMNIA_CMD_GET_FEATURES275 * command.276 */277 if (status & OMNIA_STS_FEATURES_SUPPORTED) {278 /* try read 32-bit features */279 err = omnia_cmd_read_u32(client, OMNIA_CMD_GET_FEATURES,280 &mcu->features);281 if (err) {282 /* try read 16-bit features */283 u16 features16;284 285 err = omnia_cmd_read_u16(client, OMNIA_CMD_GET_FEATURES,286 &features16);287 if (err)288 return err;289 290 mcu->features = features16;291 } else {292 if (mcu->features & OMNIA_FEAT_FROM_BIT_16_INVALID)293 mcu->features &= GENMASK(15, 0);294 }295 } else {296 dev_info(dev,297 "Your board's MCU firmware does not support feature reading.\n");298 suggest_fw_upgrade = true;299 }300 301 mcu->type = omnia_status_to_mcu_type(status);302 dev_info(dev, "MCU type %s%s\n", mcu->type,303 (mcu->features & OMNIA_FEAT_PERIPH_MCU) ?304 ", with peripheral resets wired" : "");305 306 omnia_mcu_print_version_hash(mcu, true);307 308 if (mcu->features & OMNIA_FEAT_BOOTLOADER)309 dev_warn(dev,310 "MCU is running bootloader firmware. Was firmware upgrade interrupted?\n");311 else312 omnia_mcu_print_version_hash(mcu, false);313 314 for (unsigned int i = 0; i < ARRAY_SIZE(features); i++) {315 if (mcu->features & features[i].mask)316 continue;317 318 omnia_info_missing_feature(dev, features[i].name);319 suggest_fw_upgrade = true;320 }321 322 if (suggest_fw_upgrade)323 dev_info(dev,324 "Consider upgrading MCU firmware with the omnia-mcutool utility.\n");325 326 return 0;327}328 329static int omnia_mcu_read_board_info(struct omnia_mcu *mcu)330{331 u8 reply[1 + OMNIA_BOARD_INFO_LEN];332 int err;333 334 err = omnia_cmd_read(mcu->client, OMNIA_CMD_BOARD_INFO_GET, reply,335 sizeof(reply));336 if (err)337 return err;338 339 if (reply[0] != OMNIA_BOARD_INFO_LEN)340 return -EIO;341 342 mcu->board_serial_number = get_unaligned_le64(&reply[1]);343 344 /* we can't use ether_addr_copy() because reply is not u16-aligned */345 memcpy(mcu->board_first_mac, &reply[9], sizeof(mcu->board_first_mac));346 347 mcu->board_revision = reply[15];348 349 return 0;350}351 352static int omnia_mcu_probe(struct i2c_client *client)353{354 struct device *dev = &client->dev;355 struct omnia_mcu *mcu;356 int err;357 358 if (!client->irq)359 return dev_err_probe(dev, -EINVAL, "IRQ resource not found\n");360 361 mcu = devm_kzalloc(dev, sizeof(*mcu), GFP_KERNEL);362 if (!mcu)363 return -ENOMEM;364 365 mcu->client = client;366 i2c_set_clientdata(client, mcu);367 368 err = omnia_mcu_read_features(mcu);369 if (err)370 return dev_err_probe(dev, err,371 "Cannot determine MCU supported features\n");372 373 if (mcu->features & OMNIA_FEAT_BOARD_INFO) {374 err = omnia_mcu_read_board_info(mcu);375 if (err)376 return dev_err_probe(dev, err,377 "Cannot read board info\n");378 }379 380 err = omnia_mcu_register_sys_off_and_wakeup(mcu);381 if (err)382 return err;383 384 err = omnia_mcu_register_watchdog(mcu);385 if (err)386 return err;387 388 err = omnia_mcu_register_gpiochip(mcu);389 if (err)390 return err;391 392 return omnia_mcu_register_trng(mcu);393}394 395static const struct of_device_id of_omnia_mcu_match[] = {396 { .compatible = "cznic,turris-omnia-mcu" },397 {}398};399 400static struct i2c_driver omnia_mcu_driver = {401 .probe = omnia_mcu_probe,402 .driver = {403 .name = "turris-omnia-mcu",404 .of_match_table = of_omnia_mcu_match,405 .dev_groups = omnia_mcu_groups,406 },407};408module_i2c_driver(omnia_mcu_driver);409 410MODULE_AUTHOR("Marek Behun <kabel@kernel.org>");411MODULE_DESCRIPTION("CZ.NIC's Turris Omnia MCU");412MODULE_LICENSE("GPL");413