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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
commitf4cdf7ca9a1fdcca413157df19753f388a5a224e (patch)
tree60a31895b2446cd7fa27514e8c2843534a0de0da /drivers/reset/reset-raspberrypi.c
downloadlinux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.tar.gz
linux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.zip
Merge tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediagrafted
Pull media updates from Mauro Carvalho Chehab: - v4l2-core: added ISP statistics support and per-block validation - v4l2-core: Allow unknown HDR10 white point and luminance - New camera sensors: Sony IMX678 and IMX471m, Himax HM1092 IR sensor - New codec: Milos: VPU v2.0 codec support - isp driver: gained support for Dreamchip RPPX1 ISP framework - vsp1 driver: gained support for RZ/T2H and RZ/N2H - Novalake driver: gained CVS support for new NVL hardware - dvb-core: fix feed leak on failed DMX_ADD_PID - several driver fixes, cleanups and minor improvements * tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (308 commits) media: ipu-bridge: check all DMI entries when overriding sensor rotation media: v4l2-async: avoid deleting unlinked ASC entry on link error media: rzg2l-cru: Align bytesperline to hardware DMA stride requirement media: intel/ipu6: fix async notifier cleanup leak on parse error media: staging/ipu7: fix async notifier UAF on probe error path media: amd: isp4: fix self-deadlock in isp4sd_pwron_and_init() error path media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem() media: rcar-isp: Fix VSPX reference leaks media: rcar-isp: Release ISPCORE resources media: i2c: imx415: Release runtime PM reference on VBLANK error media: i2c: imx415: Return test pattern write errors media: renesas: vsp1: Declare index variables in for loop statement media: renesas: vsp1: Make reset control optional to support platforms without a reset line media: dt-bindings: media: renesas,vsp1: Document RZ/T2H and RZ/N2H SoCs media: dt-bindings: media: renesas,fcp: Document RZ/T2H and RZ/N2H SoCs media: nxp: imx8-isi: Add additional 32-bit RGB format support media: nxp: imx8-isi: Add 16-bit raw Bayer format support media: nxp: imx8-isi: Implement per-stream reference counting for multiplexed streams media: nxp: imx8-isi: Use BIT_ULL() for 64-bit stream masks media: nxp: imx8-isi: Correct color map between V4L2 and ISI ...
Diffstat (limited to 'drivers/reset/reset-raspberrypi.c')
-rw-r--r--drivers/reset/reset-raspberrypi.c122
1 files changed, 122 insertions, 0 deletions
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 <nsaenzjulienne@suse.de>
+ */
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/reset-controller.h>
+#include <soc/bcm2835/raspberrypi-firmware.h>
+#include <dt-bindings/reset/raspberrypi,firmware-reset.h>
+
+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 <nsaenzjulienne@suse.de>");
+MODULE_DESCRIPTION("Raspberry Pi 4 firmware reset driver");
+MODULE_LICENSE("GPL");