// SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause /* * UCSI driver for STMicroelectronics STM32G0 Type-C PD controller * * Copyright (C) 2022, STMicroelectronics - All Rights Reserved * Author: Fabrice Gasnier . */ #include #include #include #include #include #include #include #include "ucsi.h" /* STM32G0 I2C bootloader addr: 0b1010001x (See AN2606) */ #define STM32G0_I2C_BL_ADDR (0xa2 >> 1) /* STM32G0 I2C bootloader max data size */ #define STM32G0_I2C_BL_SZ 256 /* STM32 I2C bootloader commands (See AN4221) */ #define STM32_CMD_GVR 0x01 /* Gets the bootloader version */ #define STM32_CMD_GVR_LEN 1 #define STM32_CMD_RM 0x11 /* Reag memory */ #define STM32_CMD_WM 0x31 /* Write memory */ #define STM32_CMD_ADDR_LEN 5 /* Address len for go, mem write... */ #define STM32_CMD_ERASE 0x44 /* Erase page, bank or all */ #define STM32_CMD_ERASE_SPECIAL_LEN 3 #define STM32_CMD_GLOBAL_MASS_ERASE 0xffff /* All-bank erase */ /* STM32 I2C bootloader answer status */ #define STM32G0_I2C_BL_ACK 0x79 #define STM32G0_I2C_BL_NACK 0x1f #define STM32G0_I2C_BL_BUSY 0x76 /* STM32G0 flash definitions */ #define STM32G0_USER_OPTION_BYTES 0x1fff7800 #define STM32G0_USER_OB_NBOOT0 BIT(26) #define STM32G0_USER_OB_NBOOT_SEL BIT(24) #define STM32G0_USER_OB_BOOT_MAIN (STM32G0_USER_OB_NBOOT0 | STM32G0_USER_OB_NBOOT_SEL) #define STM32G0_MAIN_MEM_ADDR 0x08000000 /* STM32 Firmware definitions: additional commands */ #define STM32G0_FW_GETVER 0x00 /* Gets the firmware version */ #define STM32G0_FW_GETVER_LEN 4 #define STM32G0_FW_RSTGOBL 0x21 /* Reset and go to bootloader */ #define STM32G0_FW_KEYWORD 0xa56959a6 /* ucsi_stm32g0_fw_info located at the end of the firmware */ struct ucsi_stm32g0_fw_info { u32 version; u32 keyword; }; struct ucsi_stm32g0 { struct i2c_client *client; struct i2c_client *i2c_bl; bool in_bootloader; u8 bl_version; struct completion complete; struct device *dev; unsigned long flags; #define COMMAND_PENDING 1 #define ACK_PENDING 2 const char *fw_name; struct ucsi *ucsi; bool suspended; bool wakeup_event; }; /* * Bootloader commands helpers: * - send command (2 bytes) * - check ack * Then either: * - receive data * - receive data + check ack * - send data + check ack * These operations depends on the command and have various length. */ static int ucsi_stm32g0_bl_check_ack(struct ucsi *ucsi) { struct ucsi_stm32g0 *g0 = ucsi_get_drvdata(ucsi); struct i2c_client *client = g0->i2c_bl; unsigned char ack; struct i2c_msg msg[] = { { .addr = client->addr, .flags = I2C_M_RD, .len = 1, .buf = &ack, }, }; int ret; ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg)); if (ret != ARRAY_SIZE(msg)) { dev_err(g0->dev, "i2c bl ack (%02x), error: %d\n", client->addr, ret); return ret < 0 ? ret : -EIO; } /* The 'ack' byte should contain bootloader answer: ack/nack/busy */ switch (ack) { case STM32G0_I2C_BL_ACK: return 0; case STM32G0_I2C_BL_NACK: return -ENOENT; case STM32G0_I2C_BL_BUSY: return -EBUSY; default: dev_err(g0->dev, "i2c bl ack (%02x), invalid byte: %02x\n", client->addr, ack); return -EINVAL; } } static int ucsi_stm32g0_bl_cmd_check_ack(struct ucsi *ucsi, unsigned int cmd, bool check_ack) { struct ucsi_stm32g0 *g0 = ucsi_get_drvdata(ucsi); struct i2c_client *client = g0->i2c_bl; unsigned char buf[2]; struct i2c_msg msg[] = { { .addr = client->addr, .flags = 0, .len = sizeof(buf), .buf = buf, }, }; int ret; /* * Send STM32 bootloader command format is two bytes: * - command code * - XOR'ed command code */ buf[0] = cmd; buf[1] = cmd ^ 0xff; ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg)); if (ret != ARRAY_SIZE(msg)) { dev_dbg(g0->dev, "i2c bl cmd %d (%02x), error: %d\n", cmd, client->addr, ret); return ret < 0 ? ret : -EIO; } if (check_ack) return ucsi_stm32g0_bl_check_ack(ucsi); return 0; } static int ucsi_stm32g0_bl_cmd(struct ucsi *ucsi, unsigned int cmd) { return ucsi_stm32g0_bl_cmd_check_ack(ucsi, cmd, true); } static int ucsi_stm32g0_bl_rcv_check_ack(struct ucsi *ucsi, void *data, size_t len, bool check_ack) { struct ucsi_stm32g0 *g0 = ucsi_get_drvdata(ucsi); struct i2c_client *client = g0->i2c_bl; struct i2c_msg msg[] = { { .addr = client->addr, .flags = I2C_M_RD, .len = len, .buf = data, }, }; int ret; ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg)); if (ret != ARRAY_SIZE(msg)) { dev_err(g0->dev, "i2c bl rcv %02x, error: %d\n", client->addr, ret); return ret < 0 ? ret : -EIO; } if (check_ack) return ucsi_stm32g0_bl_check_ack(ucsi); return 0; } static int ucsi_stm32g0_bl_rcv(struct ucsi *ucsi, void *data, size_t len) { return ucsi_stm32g0_bl_rcv_check_ack(ucsi, data, len, true); } static int ucsi_stm32g0_bl_rcv_woack(struct ucsi *ucsi, void *data, size_t len) { return ucsi_stm32g0_bl_rcv_check_ack(ucsi, data, len, false); } static int ucsi_stm32g0_bl_send(struct ucsi *ucsi, void *data, size_t len) { struct ucsi_stm32g0 *g0 = ucsi_get_drvdata(ucsi); struct i2c_client *client = g0->i2c_bl; struct i2c_msg msg[] = { { .addr = client->addr, .flags = 0, .len = len, .buf = data, }, }; int ret; ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg)); if (ret != ARRAY_SIZE(msg)) { dev_err(g0->dev, "i2c bl send %02x, error: %d\n", client->addr, ret); return ret < 0 ? ret : -EIO; } return ucsi_stm32g0_bl_check_ack(ucsi); } /* Bootloader commands */ static int ucsi_stm32g0_bl_get_version(struct ucsi *ucsi, u8 *bl_version) { int ret; ret = ucsi_stm32g0_bl_cmd(ucsi, STM32_CMD_GVR); if (ret) return ret; return ucsi_stm32g0_bl_rcv(ucsi, bl_version, STM32_CMD_GVR_LEN); } static int ucsi_stm32g0_bl_send_addr(struct ucsi *ucsi, u32 addr) { u8 data8[STM32_CMD_ADDR_LEN]; /* Address format: 4 bytes addr (MSB first) + XOR'ed addr bytes */ put_unaligned_be32(addr, data8); data8[4] = data8[0] ^ data8[1] ^ data8[2] ^ data8[3]; return ucsi_stm32g0_bl_send(ucsi, data8, STM32_CMD_ADDR_LEN); } static int ucsi_stm32g0_bl_global_mass_erase(struct ucsi *ucsi) { u8 data8[4]; u16 *data16 = (u16 *)&data8[0]; int ret; data16[0] = STM32_CMD_GLOBAL_MASS_ERASE; data8[2] = data8[0] ^ data8[1]; ret = ucsi_stm32g0_bl_cmd(ucsi, STM32_CMD_ERASE); if (ret) return ret; return ucsi_stm32g0_bl_send(ucsi, data8, STM32_CMD_ERASE_SPECIAL_LEN); } static int ucsi_stm32g0_bl_write(struct ucsi *ucsi, u32 addr, const void *data, size_t len) { u8 *data8; int i, ret; if (!len || len > STM32G0_I2C_BL_SZ) return -EINVAL; /* Write memory: len bytes -1, data up to 256 bytes + XOR'ed bytes */ data8 = kmalloc(STM32G0_I2C_BL_SZ + 2, GFP_KERNEL); if (!data8) return -ENOMEM; ret = ucsi_stm32g0_bl_cmd(ucsi, STM32_CMD_WM); if (ret) goto free; ret = ucsi_stm32g0_bl_send_addr(ucsi, addr); if (ret) goto free; data8[0] = len - 1; memcpy(data8 + 1, data, len); data8[len + 1] = data8[0]; for (i = 1; i <= len; i++) data8[len + 1] ^= data8[i]; ret = ucsi_stm32g0_bl_send(ucsi, data8, len + 2); free: kfree(data8); return ret; } static int ucsi_stm32g0_bl_read(struct ucsi *ucsi, u32 addr, void *data, size_t len) { int ret; if (!len || len > STM32G0_I2C_BL_SZ) return -EINVAL; ret = ucsi_stm32g0_bl_cmd(ucsi, STM32_CMD_RM); if (ret) return ret; ret = ucsi_stm32g0_bl_send_addr(ucsi, addr); if (ret) return ret; ret = ucsi_stm32g0_bl_cmd(ucsi, len - 1); if (ret) return ret; return ucsi_stm32g0_bl_rcv_woack(ucsi, data, len); } /* Firmware commands (the same address as the bootloader) */ static int ucsi_stm32g0_fw_cmd(struct ucsi *ucsi, unsigned int cmd) { return ucsi_stm32g0_bl_cmd_check_ack(ucsi, cmd, false); } static int ucsi_stm32g0_fw_rcv(struct ucsi *ucsi, void *data, size_t len) { return ucsi_stm32g0_bl_rcv_woack(ucsi, data, len); } /* UCSI ops */ static int ucsi_stm32g0_read(struct ucsi *ucsi, unsigned int offset, void *val, size_t len) { struct ucsi_stm32g0 *g0 = ucsi_get_drvdata(ucsi); struct i2c_client *client = g0->client; u8 reg = offset; struct i2c_msg msg[] = { { .addr = client->addr, .flags = 0, .len = 1, .buf = ®, }, { .addr = client->addr, .flags = I2C_M_RD, .len = len, .buf = val, }, }; int ret; ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg)); if (ret != ARRAY_SIZE(msg)) { dev_err(g0->dev, "i2c read %02x, %02x error: %d\n", client->addr, reg, ret); return ret < 0 ? ret : -EIO; } return 0; } static int ucsi_stm32g0_async_write(struct ucsi *ucsi, unsigned int offset, const void *val, size_t len) { struct ucsi_stm32g0 *g0 = ucsi_get_drvdata(ucsi); struct i2c_client *client = g0->client; struct i2c_msg msg[] = { { .addr = client->addr, .flags = 0, } }; unsigned char *buf; int ret; buf = kmalloc(len + 1, GFP_KERNEL); if (!buf) return -ENOMEM; buf[0] = offset; memcpy(&buf[1], val, len); msg[0].len = len + 1; msg[0].buf = buf; ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg)); kfree(buf); if (ret != ARRAY_SIZE(msg)) { dev_err(g0->dev, "i2c write %02x, %02x error: %d\n", client->addr, offset, ret); return ret < 0 ? ret : -EIO; } return 0; } static int ucsi_stm32g0_sync_write(struct ucsi *ucsi, unsigned int offset, const void *val, size_t len) { struct ucsi_stm32g0 *g0 = ucsi_get_drvdata(ucsi); bool ack = UCSI_COMMAND(*(u64 *)val) == UCSI_ACK_CC_CI; int ret; if (ack) set_bit(ACK_PENDING, &g0->flags); else set_bit(COMMAND_PENDING, &g0->flags); ret = ucsi_stm32g0_async_write(ucsi, offset, val, len); if (ret) goto out_clear_bit; if (!wait_for_completion_timeout(&g0->complete, msecs_to_jiffies(5000))) ret = -ETIMEDOUT; else return 0; out_clear_bit: if (ack) clear_bit(ACK_PENDING, &g0->flags); else clear_bit(COMMAND_PENDING, &g0->flags); return ret; } static irqreturn_t ucsi_stm32g0_irq_handler(int irq, void *data) { struct ucsi_stm32g0 *g0 = data; u32 cci; int ret; if (g0->suspended) g0->wakeup_event = true; ret = ucsi_stm32g0_read(g0->ucsi, UCSI_CCI, &cci, sizeof(cci)); if (ret) return IRQ_NONE; if (UCSI_CCI_CONNECTOR(cci)) ucsi_connector_change(g0->ucsi, UCSI_CCI_CONNECTOR(cci)); if (cci & UCSI_CCI_ACK_COMPLETE && test_and_clear_bit(ACK_PENDING, &g0->flags)) complete(&g0->complete); if (cci & UCSI_CCI_COMMAND_COMPLETE && test_and_clear_bit(COMMAND_PENDING, &g0->flags)) complete(&g0->complete); return IRQ_HANDLED; } static const struct ucsi_operations ucsi_stm32g0_ops = { .read = ucsi_stm32g0_read, .sync_write = ucsi_stm32g0_sync_write, .async_write = ucsi_stm32g0_async_write, }; static int ucsi_stm32g0_register(struct ucsi *ucsi) { struct ucsi_stm32g0 *g0 = ucsi_get_drvdata(ucsi); struct i2c_client *client = g0->client; int ret; /* Request alert interrupt */ ret = request_threaded_irq(client->irq, NULL, ucsi_stm32g0_irq_handler, IRQF_ONESHOT, dev_name(g0->dev), g0); if (ret) { dev_err(g0->dev, "request IRQ failed: %d\n", ret); return ret; } ret = ucsi_register(ucsi); if (ret) { dev_err_probe(g0->dev, ret, "ucsi_register failed\n"); free_irq(client->irq, g0); return ret; } return 0; } static void ucsi_stm32g0_unregister(struct ucsi *ucsi) { struct ucsi_stm32g0 *g0 = ucsi_get_drvdata(ucsi); struct i2c_client *client = g0->client; ucsi_unregister(ucsi); free_irq(client->irq, g0); } static void ucsi_stm32g0_fw_cb(const struct firmware *fw, void *context) { struct ucsi_stm32g0 *g0; const u8 *data, *end; const struct ucsi_stm32g0_fw_info *fw_info; u32 addr = STM32G0_MAIN_MEM_ADDR, ob, fw_version; int ret, size; if (!context) return; g0 = ucsi_get_drvdata(context); if (!fw) goto fw_release; fw_info = (struct ucsi_stm32g0_fw_info *)(fw->data + fw->size - sizeof(*fw_info)); if (!g0->in_bootloader) { /* Read running firmware version */ ret = ucsi_stm32g0_fw_cmd(g0->ucsi, STM32G0_FW_GETVER); if (ret) { dev_err(g0->dev, "Get version cmd failed %d\n", ret); goto fw_release; } ret = ucsi_stm32g0_fw_rcv(g0->ucsi, &fw_version, STM32G0_FW_GETVER_LEN); if (ret) { dev_err(g0->dev, "Get version failed %d\n", ret); goto fw_release; } /* Sanity check on keyword and firmware version */ if (fw_info->keyword != STM32G0_FW_KEYWORD || fw_info->version == fw_version) goto fw_release; dev_info(g0->dev, "Flashing FW: %08x (%08x cur)\n", fw_info->version, fw_version); /* Switch to bootloader mode */ ucsi_stm32g0_unregister(g0->ucsi); ret = ucsi_stm32g0_fw_cmd(g0->ucsi, STM32G0_FW_RSTGOBL); if (ret) { dev_err(g0->dev, "bootloader cmd failed %d\n", ret); goto fw_release; } g0->in_bootloader = true; /* STM32G0 reboot delay */ msleep(100); } ret = ucsi_stm32g0_bl_global_mass_erase(g0->ucsi); if (ret) { dev_err(g0->dev, "Erase failed %d\n", ret); goto fw_release; } data = fw->data; end = fw->data + fw->size; while (data < end) { if ((end - data) < STM32G0_I2C_BL_SZ) size = end - data; else size = STM32G0_I2C_BL_SZ; ret = ucsi_stm32g0_bl_write(g0->ucsi, addr, data, size); if (ret) { dev_err(g0->dev, "Write failed %d\n", ret); goto fw_release; } addr += size; data += size; } dev_dbg(g0->dev, "Configure to boot from main flash\n"); ret = ucsi_stm32g0_bl_read(g0->ucsi, STM32G0_USER_OPTION_BYTES, &ob, sizeof(ob)); if (ret) { dev_err(g0->dev, "read user option bytes failed %d\n", ret); goto fw_release; } dev_dbg(g0->dev, "STM32G0_USER_OPTION_BYTES 0x%08x\n", ob); /* Configure user option bytes to boot from main flash next time */ ob |= STM32G0_USER_OB_BOOT_MAIN; /* Writing option bytes will also reset G0 for updates to be loaded */ ret = ucsi_stm32g0_bl_write(g0->ucsi, STM32G0_USER_OPTION_BYTES, &ob, sizeof(ob)); if (ret) { dev_err(g0->dev, "write user option bytes failed %d\n", ret); goto fw_release; } dev_info(g0->dev, "Starting, option bytes:0x%08x\n", ob); /* STM32G0 FW boot delay */ msleep(500); /* Register UCSI interface */ if (!ucsi_stm32g0_register(g0->ucsi)) g0->in_bootloader = false; fw_release: release_firmware(fw); } static int ucsi_stm32g0_probe_bootloader(struct ucsi *ucsi) { struct ucsi_stm32g0 *g0 = ucsi_get_drvdata(ucsi); int ret; u16 ucsi_version; /* firmware-name is optional */ if (device_property_present(g0->dev, "firmware-name")) { ret = device_property_read_string(g0->dev, "firmware-name", &g0->fw_name); if (ret < 0) return dev_err_probe(g0->dev, ret, "Error reading firmware-name\n"); } if (g0->fw_name) { /* STM32G0 in bootloader mode communicates at reserved address 0x51 */ g0->i2c_bl = i2c_new_dummy_device(g0->client->adapter, STM32G0_I2C_BL_ADDR); if (IS_ERR(g0->i2c_bl)) { ret = dev_err_probe(g0->dev, PTR_ERR(g0->i2c_bl), "Failed to register bootloader I2C address\n"); return ret; } } /* * Try to guess if the STM32G0 is running a UCSI firmware. First probe the UCSI FW at its * i2c address. Fallback to bootloader i2c address only if firmware-name is specified. */ ret = ucsi_stm32g0_read(ucsi, UCSI_VERSION, &ucsi_version, sizeof(ucsi_version)); if (!ret || !g0->fw_name) return ret; /* Speculatively read the bootloader version that has a known length. */ ret = ucsi_stm32g0_bl_get_version(ucsi, &g0->bl_version); if (ret < 0) { i2c_unregister_device(g0->i2c_bl); return ret; } /* Device in bootloader mode */ g0->in_bootloader = true; dev_info(g0->dev, "Bootloader Version 0x%02x\n", g0->bl_version); return 0; } static int ucsi_stm32g0_probe(struct i2c_client *client) { struct device *dev = &client->dev; struct ucsi_stm32g0 *g0; int ret; g0 = devm_kzalloc(dev, sizeof(*g0), GFP_KERNEL); if (!g0) return -ENOMEM; g0->dev = dev; g0->client = client; init_completion(&g0->complete); i2c_set_clientdata(client, g0); g0->ucsi = ucsi_create(dev, &ucsi_stm32g0_ops); if (IS_ERR(g0->ucsi)) return PTR_ERR(g0->ucsi); ucsi_set_drvdata(g0->ucsi, g0); ret = ucsi_stm32g0_probe_bootloader(g0->ucsi); if (ret < 0) goto destroy; /* * Don't register in bootloader mode: wait for the firmware to be loaded and started before * registering UCSI device. */ if (!g0->in_bootloader) { ret = ucsi_stm32g0_register(g0->ucsi); if (ret < 0) goto freei2c; } if (g0->fw_name) { /* * Asynchronously flash (e.g. bootloader mode) or update the running firmware, * not to hang the boot process */ ret = request_firmware_nowait(THIS_MODULE, FW_ACTION_UEVENT, g0->fw_name, g0->dev, GFP_KERNEL, g0->ucsi, ucsi_stm32g0_fw_cb); if (ret < 0) { dev_err_probe(dev, ret, "firmware request failed\n"); goto unregister; } } return 0; unregister: if (!g0->in_bootloader) ucsi_stm32g0_unregister(g0->ucsi); freei2c: if (g0->fw_name) i2c_unregister_device(g0->i2c_bl); destroy: ucsi_destroy(g0->ucsi); return ret; } static void ucsi_stm32g0_remove(struct i2c_client *client) { struct ucsi_stm32g0 *g0 = i2c_get_clientdata(client); if (!g0->in_bootloader) ucsi_stm32g0_unregister(g0->ucsi); if (g0->fw_name) i2c_unregister_device(g0->i2c_bl); ucsi_destroy(g0->ucsi); } static int ucsi_stm32g0_suspend(struct device *dev) { struct ucsi_stm32g0 *g0 = dev_get_drvdata(dev); struct i2c_client *client = g0->client; if (g0->in_bootloader) return 0; /* Keep the interrupt disabled until the i2c bus has been resumed */ disable_irq(client->irq); g0->suspended = true; g0->wakeup_event = false; if (device_may_wakeup(dev) || device_wakeup_path(dev)) enable_irq_wake(client->irq); return 0; } static int ucsi_stm32g0_resume(struct device *dev) { struct ucsi_stm32g0 *g0 = dev_get_drvdata(dev); struct i2c_client *client = g0->client; if (g0->in_bootloader) return 0; if (device_may_wakeup(dev) || device_wakeup_path(dev)) disable_irq_wake(client->irq); enable_irq(client->irq); /* Enforce any pending handler gets called to signal a wakeup_event */ synchronize_irq(client->irq); if (g0->wakeup_event) pm_wakeup_event(g0->dev, 0); g0->suspended = false; return 0; } static DEFINE_SIMPLE_DEV_PM_OPS(ucsi_stm32g0_pm_ops, ucsi_stm32g0_suspend, ucsi_stm32g0_resume); static const struct of_device_id __maybe_unused ucsi_stm32g0_typec_of_match[] = { { .compatible = "st,stm32g0-typec" }, {}, }; MODULE_DEVICE_TABLE(of, ucsi_stm32g0_typec_of_match); static const struct i2c_device_id ucsi_stm32g0_typec_i2c_devid[] = { {"stm32g0-typec", 0}, {}, }; MODULE_DEVICE_TABLE(i2c, ucsi_stm32g0_typec_i2c_devid); static struct i2c_driver ucsi_stm32g0_i2c_driver = { .driver = { .name = "ucsi-stm32g0-i2c", .of_match_table = of_match_ptr(ucsi_stm32g0_typec_of_match), .pm = pm_sleep_ptr(&ucsi_stm32g0_pm_ops), }, .probe = ucsi_stm32g0_probe, .remove = ucsi_stm32g0_remove, .id_table = ucsi_stm32g0_typec_i2c_devid }; module_i2c_driver(ucsi_stm32g0_i2c_driver); MODULE_AUTHOR("Fabrice Gasnier "); MODULE_DESCRIPTION("STMicroelectronics STM32G0 Type-C controller"); MODULE_LICENSE("Dual BSD/GPL"); MODULE_ALIAS("platform:ucsi-stm32g0");