From 4352b8aee98005853aa63f57d6377282de17a33f Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 23 Aug 2026 13:28:57 -0700 Subject: Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ... --- drivers/reset/reset-raspberrypi.c | 122 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 122 insertions(+) create mode 100644 drivers/reset/reset-raspberrypi.c (limited to 'drivers/reset/reset-raspberrypi.c') diff --git a/drivers/reset/reset-raspberrypi.c b/drivers/reset/reset-raspberrypi.c new file mode 100644 index 000000000..fa23db554 --- /dev/null +++ b/drivers/reset/reset-raspberrypi.c @@ -0,0 +1,122 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Raspberry Pi 4 firmware reset driver + * + * Copyright (C) 2020 Nicolas Saenz Julienne + */ +#include +#include +#include +#include +#include +#include +#include +#include + +struct rpi_reset { + struct reset_controller_dev rcdev; + struct rpi_firmware *fw; +}; + +static inline struct rpi_reset *to_rpi(struct reset_controller_dev *rcdev) +{ + return container_of(rcdev, struct rpi_reset, rcdev); +} + +static int rpi_reset_reset(struct reset_controller_dev *rcdev, unsigned long id) +{ + struct rpi_reset *priv = to_rpi(rcdev); + u32 dev_addr; + int ret; + + switch (id) { + case RASPBERRYPI_FIRMWARE_RESET_ID_USB: + /* + * The Raspberry Pi 4 gets its USB functionality from VL805, a + * PCIe chip that implements xHCI. After a PCI reset, VL805's + * firmware may either be loaded directly from an EEPROM or, if + * not present, by the SoC's co-processor, VideoCore. rpi's + * VideoCore OS contains both the non public firmware load + * logic and the VL805 firmware blob. This triggers the + * aforementioned process. + * + * The pci device address is expected is expected by the + * firmware encoded like this: + * + * PCI_BUS << 20 | PCI_SLOT << 15 | PCI_FUNC << 12 + * + * But since rpi's PCIe is hardwired, we know the address in + * advance. + */ + dev_addr = 0x100000; + ret = rpi_firmware_property(priv->fw, RPI_FIRMWARE_NOTIFY_XHCI_RESET, + &dev_addr, sizeof(dev_addr)); + if (ret) + return ret; + + /* Wait for vl805 to startup */ + usleep_range(200, 1000); + break; + + default: + return -EINVAL; + } + + return 0; +} + +static const struct reset_control_ops rpi_reset_ops = { + .reset = rpi_reset_reset, +}; + +static int rpi_reset_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct rpi_firmware *fw; + struct device_node *np; + struct rpi_reset *priv; + + np = of_get_parent(dev->of_node); + if (!np) { + dev_err(dev, "Missing firmware node\n"); + return -ENOENT; + } + + fw = devm_rpi_firmware_get(&pdev->dev, np); + of_node_put(np); + if (!fw) + return -EPROBE_DEFER; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + dev_set_drvdata(dev, priv); + + priv->fw = fw; + priv->rcdev.owner = THIS_MODULE; + priv->rcdev.nr_resets = RASPBERRYPI_FIRMWARE_RESET_NUM_IDS; + priv->rcdev.ops = &rpi_reset_ops; + priv->rcdev.of_node = dev->of_node; + + return devm_reset_controller_register(dev, &priv->rcdev); +} + +static const struct of_device_id rpi_reset_of_match[] = { + { .compatible = "raspberrypi,firmware-reset" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, rpi_reset_of_match); + +static struct platform_driver rpi_reset_driver = { + .probe = rpi_reset_probe, + .driver = { + .name = "raspberrypi-reset", + .of_match_table = rpi_reset_of_match, + }, +}; +module_platform_driver(rpi_reset_driver); + +MODULE_AUTHOR("Nicolas Saenz Julienne "); +MODULE_DESCRIPTION("Raspberry Pi 4 firmware reset driver"); +MODULE_LICENSE("GPL"); -- cgit v1.3.1