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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-30 09:22:00 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-30 09:22:00 -0700
commit034dd340b08be1f2f0477ad16131d609f9dbd53c (patch)
tree2536f4b2d7893ccd916b5abdf3c454ad6edc03c2 /drivers/phy/phy-google-usb.c
downloadlinux-stable-034dd340b08be1f2f0477ad16131d609f9dbd53c.tar.gz
linux-stable-034dd340b08be1f2f0477ad16131d609f9dbd53c.zip
Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted
Pull tracing fixes from Steven Rostedt: - Fix error output of boot instance creation failure Currently if a boot instance creation fails, instead of printing out the name of the instance that failed, it prints "(null)". That is because it prints "cur_str" that had already been processed by strsep(). Print the saved name instead. While at it, print the error code of the failure. - Fix use-after-free for same named historgrams Histograms can be named so that they can be used in multiple events. But if the named histogram has a variable attached, the second event that uses the named histogram which duplicates it and needs to free the original after duplication leaves the old variable in place and still visible. If another histogram uses than variable, it will use the stale one which will try to reference the freed duplicate histogram and crash the kernel. Free the duplicate variables along with the duplicated histogram data. - Check return value of kthread_run() in event self test The events self tests uses a kthread for testing but does not check if it succeeded in creating a kthread. If the kthread creation were to fail, the code will still try to call kthread_stop() on the error returned. - Fix race between reading trace_pipe and updating subbuffer size If a user is reading the trace_pipe file at the same time they update the ring buffer sub-buffer size, can cause the trace_pipe read to read stale data. Add trace_access_lock() around updating the ring buffer sub-buffer size. - Fix eventfs_inode on failure path in creation of the events directory In the creation of the "events" directory, if after allocating the eventfs_inode a failure is detected, it calls cleanup_ei() which calls free_ei(). The free_ei() will test if eventfs_inode being freed has no children. It is a bug if it does. But on the failure case of the creation of the "events" directory, the children lists have not yet been initialized and the free will trigger a warning because list_empty() on an uninitialized list returns false. Move the initialization into init_ei() where it makes more sense and makes sure that a created eventfs_inode has its lists initialized upon creation. - Check return value of kthread_run() in ftrace direct sample code The sample code that shows how to use the ftrace direct calls does not test the return of kthread_run() to see if it succeeds. Return a failure if the kthread_run() doesn't succeed. - Clear user events state on fork in case of alloc failure On fork, the child gets a pointer to the parent's user events state. It makes a copy of it then updates the child's pointer to it. But if the allocation fails, the duplication function leaves the child with a pointer to its parent's descriptor. When the child cleans up its data, it will free the parent's descriptor while the parent is still using it. In the duplication function, set the child's user_event_mm to NULL before testing if the allocation succeeded, and when it exits it will not free the parent's descriptor. - Fix retry exhaustion in simple ring buffer reader swap simple_ring_buffer_swap_reader_page() starts with retry set to 8 and post-decrements it only after a failed link replacement. On the final attempt, a successful replacement leaves retry at zero, while a failed replacement leaves it at -1. But the check for success expects the retry value to be non-zero and exits with an error on zero. This is the opposite result. Fix it. - Fail nicely when the remote swap_reader_page() returns an error Currently, if the swap_reader_page() of a remote buffer fails, it triggers a WARN_ON_ONCE() and continues normally. Instead, have it exit with an error and a pr_warn() print instead of a full WARNING. * tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Stop remote reader update when page swap fails tracing: Fix retry exhaustion in simple ring buffer reader swap tracing/user_events: Clear copied tracing state before fork duplication samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify eventfs: Initialize ei->children and ei->list in init_ei() tracing: Fix use-after-free in trace_pipe read on sub-buffer order change tracing: Fix crash passing ERR_PTR to kthread_stop() tracing: Fix use-after-free with same-name named triggers tracing: Fix logged instance name on creation failure
Diffstat (limited to 'drivers/phy/phy-google-usb.c')
-rw-r--r--drivers/phy/phy-google-usb.c296
1 files changed, 296 insertions, 0 deletions
diff --git a/drivers/phy/phy-google-usb.c b/drivers/phy/phy-google-usb.c
new file mode 100644
index 000000000..ab20bc20f
--- /dev/null
+++ b/drivers/phy/phy-google-usb.c
@@ -0,0 +1,296 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * phy-google-usb.c - Google USB PHY driver
+ *
+ * Copyright (C) 2025, Google LLC
+ */
+
+#include <linux/bitfield.h>
+#include <linux/cleanup.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/reset.h>
+#include <linux/usb/typec_mux.h>
+
+#define USBCS_USB2PHY_CFG19_OFFSET 0x0
+#define USBCS_USB2PHY_CFG19_PHY_CFG_PLL_FB_DIV GENMASK(19, 8)
+
+#define USBCS_USB2PHY_CFG21_OFFSET 0x8
+#define USBCS_USB2PHY_CFG21_PHY_ENABLE BIT(12)
+#define USBCS_USB2PHY_CFG21_REF_FREQ_SEL GENMASK(15, 13)
+#define USBCS_USB2PHY_CFG21_PHY_TX_DIG_BYPASS_SEL BIT(19)
+
+#define USBCS_PHY_CFG1_OFFSET 0x28
+#define USBCS_PHY_CFG1_SYS_VBUSVALID BIT(17)
+
+enum google_usb_phy_id {
+ GOOGLE_USB2_PHY,
+ GOOGLE_USB_PHY_NUM,
+};
+
+struct google_usb_phy_instance {
+ struct google_usb_phy *parent;
+ unsigned int index;
+ struct phy *phy;
+ unsigned int num_clks;
+ struct clk_bulk_data *clks;
+ unsigned int num_rsts;
+ struct reset_control_bulk_data *rsts;
+};
+
+struct google_usb_phy {
+ struct device *dev;
+ struct regmap *usb_cfg_regmap;
+ unsigned int usb2_cfg_offset;
+ void __iomem *usbdp_top_base;
+ struct google_usb_phy_instance *insts;
+ /*
+ * Protect phy registers from concurrent access, specifically via
+ * google_usb_set_orientation callback.
+ */
+ struct mutex phy_mutex;
+ struct typec_switch_dev *sw;
+ enum typec_orientation orientation;
+};
+
+static void set_vbus_valid(struct google_usb_phy *gphy)
+{
+ u32 reg;
+
+ if (gphy->orientation == TYPEC_ORIENTATION_NONE) {
+ reg = readl(gphy->usbdp_top_base + USBCS_PHY_CFG1_OFFSET);
+ reg &= ~USBCS_PHY_CFG1_SYS_VBUSVALID;
+ writel(reg, gphy->usbdp_top_base + USBCS_PHY_CFG1_OFFSET);
+ } else {
+ reg = readl(gphy->usbdp_top_base + USBCS_PHY_CFG1_OFFSET);
+ reg |= USBCS_PHY_CFG1_SYS_VBUSVALID;
+ writel(reg, gphy->usbdp_top_base + USBCS_PHY_CFG1_OFFSET);
+ }
+}
+
+static int google_usb_set_orientation(struct typec_switch_dev *sw,
+ enum typec_orientation orientation)
+{
+ struct google_usb_phy *gphy = typec_switch_get_drvdata(sw);
+
+ dev_dbg(gphy->dev, "set orientation %d\n", orientation);
+
+ gphy->orientation = orientation;
+
+ if (pm_runtime_suspended(gphy->dev))
+ return 0;
+
+ guard(mutex)(&gphy->phy_mutex);
+
+ set_vbus_valid(gphy);
+
+ return 0;
+}
+
+static int google_usb2_phy_init(struct phy *_phy)
+{
+ struct google_usb_phy_instance *inst = phy_get_drvdata(_phy);
+ struct google_usb_phy *gphy = inst->parent;
+ u32 reg;
+ int ret;
+
+ dev_dbg(gphy->dev, "initializing usb2 phy\n");
+
+ guard(mutex)(&gphy->phy_mutex);
+
+ regmap_read(gphy->usb_cfg_regmap, gphy->usb2_cfg_offset + USBCS_USB2PHY_CFG21_OFFSET, &reg);
+ reg &= ~USBCS_USB2PHY_CFG21_PHY_TX_DIG_BYPASS_SEL;
+ reg &= ~USBCS_USB2PHY_CFG21_REF_FREQ_SEL;
+ reg |= FIELD_PREP(USBCS_USB2PHY_CFG21_REF_FREQ_SEL, 0);
+ regmap_write(gphy->usb_cfg_regmap, gphy->usb2_cfg_offset + USBCS_USB2PHY_CFG21_OFFSET, reg);
+
+ regmap_read(gphy->usb_cfg_regmap, gphy->usb2_cfg_offset + USBCS_USB2PHY_CFG19_OFFSET, &reg);
+ reg &= ~USBCS_USB2PHY_CFG19_PHY_CFG_PLL_FB_DIV;
+ reg |= FIELD_PREP(USBCS_USB2PHY_CFG19_PHY_CFG_PLL_FB_DIV, 368);
+ regmap_write(gphy->usb_cfg_regmap, gphy->usb2_cfg_offset + USBCS_USB2PHY_CFG19_OFFSET, reg);
+
+ set_vbus_valid(gphy);
+
+ ret = clk_bulk_prepare_enable(inst->num_clks, inst->clks);
+ if (ret)
+ return ret;
+
+ ret = reset_control_bulk_deassert(inst->num_rsts, inst->rsts);
+ if (ret) {
+ clk_bulk_disable_unprepare(inst->num_clks, inst->clks);
+ return ret;
+ }
+
+ regmap_read(gphy->usb_cfg_regmap, gphy->usb2_cfg_offset + USBCS_USB2PHY_CFG21_OFFSET, &reg);
+ reg |= USBCS_USB2PHY_CFG21_PHY_ENABLE;
+ regmap_write(gphy->usb_cfg_regmap, gphy->usb2_cfg_offset + USBCS_USB2PHY_CFG21_OFFSET, reg);
+
+ return 0;
+}
+
+static int google_usb2_phy_exit(struct phy *_phy)
+{
+ struct google_usb_phy_instance *inst = phy_get_drvdata(_phy);
+ struct google_usb_phy *gphy = inst->parent;
+ u32 reg;
+
+ dev_dbg(gphy->dev, "exiting usb2 phy\n");
+
+ guard(mutex)(&gphy->phy_mutex);
+
+ regmap_read(gphy->usb_cfg_regmap, gphy->usb2_cfg_offset + USBCS_USB2PHY_CFG21_OFFSET, &reg);
+ reg &= ~USBCS_USB2PHY_CFG21_PHY_ENABLE;
+ regmap_write(gphy->usb_cfg_regmap, gphy->usb2_cfg_offset + USBCS_USB2PHY_CFG21_OFFSET, reg);
+
+ reset_control_bulk_assert(inst->num_rsts, inst->rsts);
+ clk_bulk_disable_unprepare(inst->num_clks, inst->clks);
+
+ return 0;
+}
+
+static const struct phy_ops google_usb2_phy_ops = {
+ .init = google_usb2_phy_init,
+ .exit = google_usb2_phy_exit,
+};
+
+static struct phy *google_usb_phy_xlate(struct device *dev,
+ const struct of_phandle_args *args)
+{
+ struct google_usb_phy *gphy = dev_get_drvdata(dev);
+
+ if (args->args[0] >= GOOGLE_USB_PHY_NUM) {
+ dev_err(dev, "invalid PHY index requested from DT\n");
+ return ERR_PTR(-ENODEV);
+ }
+ return gphy->insts[args->args[0]].phy;
+}
+
+static int google_usb_phy_probe(struct platform_device *pdev)
+{
+ struct typec_switch_desc sw_desc = { };
+ struct google_usb_phy_instance *inst;
+ struct phy_provider *phy_provider;
+ struct device *dev = &pdev->dev;
+ struct google_usb_phy *gphy;
+ struct phy *phy;
+ u32 args[1];
+ int ret;
+
+ gphy = devm_kzalloc(dev, sizeof(*gphy), GFP_KERNEL);
+ if (!gphy)
+ return -ENOMEM;
+
+ dev_set_drvdata(dev, gphy);
+ gphy->dev = dev;
+
+ ret = devm_mutex_init(dev, &gphy->phy_mutex);
+ if (ret)
+ return ret;
+
+ gphy->usb_cfg_regmap =
+ syscon_regmap_lookup_by_phandle_args(dev->of_node,
+ "google,usb-cfg-csr",
+ ARRAY_SIZE(args), args);
+ if (IS_ERR(gphy->usb_cfg_regmap)) {
+ return dev_err_probe(dev, PTR_ERR(gphy->usb_cfg_regmap),
+ "invalid usb cfg csr\n");
+ }
+
+ gphy->usb2_cfg_offset = args[0];
+
+ gphy->usbdp_top_base = devm_platform_ioremap_resource_byname(pdev,
+ "usbdp_top");
+ if (IS_ERR(gphy->usbdp_top_base))
+ return dev_err_probe(dev, PTR_ERR(gphy->usbdp_top_base),
+ "invalid usbdp top\n");
+
+ gphy->insts = devm_kcalloc(dev, GOOGLE_USB_PHY_NUM, sizeof(*gphy->insts), GFP_KERNEL);
+ if (!gphy->insts)
+ return -ENOMEM;
+
+ inst = &gphy->insts[GOOGLE_USB2_PHY];
+ inst->parent = gphy;
+ inst->index = GOOGLE_USB2_PHY;
+ phy = devm_phy_create(dev, NULL, &google_usb2_phy_ops);
+ if (IS_ERR(phy))
+ return dev_err_probe(dev, PTR_ERR(phy),
+ "failed to create usb2 phy instance\n");
+ inst->phy = phy;
+ phy_set_drvdata(phy, inst);
+
+ inst->num_clks = 2;
+ inst->clks = devm_kcalloc(dev, inst->num_clks, sizeof(*inst->clks), GFP_KERNEL);
+ if (!inst->clks)
+ return -ENOMEM;
+ inst->clks[0].id = "usb2";
+ inst->clks[1].id = "usb2_apb";
+ ret = devm_clk_bulk_get(dev, inst->num_clks, inst->clks);
+ if (ret)
+ return dev_err_probe(dev, ret, "failed to get u2 phy clks\n");
+
+ inst->num_rsts = 2;
+ inst->rsts = devm_kcalloc(dev, inst->num_rsts, sizeof(*inst->rsts), GFP_KERNEL);
+ if (!inst->rsts)
+ return -ENOMEM;
+ inst->rsts[0].id = "usb2";
+ inst->rsts[1].id = "usb2_apb";
+ ret = devm_reset_control_bulk_get_exclusive(dev, inst->num_rsts, inst->rsts);
+ if (ret)
+ return dev_err_probe(dev, ret, "failed to get u2 phy resets\n");
+
+ phy_provider = devm_of_phy_provider_register(dev, google_usb_phy_xlate);
+ if (IS_ERR(phy_provider))
+ return dev_err_probe(dev, PTR_ERR(phy_provider),
+ "failed to register phy provider\n");
+
+ pm_runtime_enable(dev);
+
+ sw_desc.fwnode = dev_fwnode(dev);
+ sw_desc.drvdata = gphy;
+ sw_desc.name = fwnode_get_name(dev_fwnode(dev));
+ sw_desc.set = google_usb_set_orientation;
+
+ gphy->sw = typec_switch_register(dev, &sw_desc);
+ if (IS_ERR(gphy->sw))
+ return dev_err_probe(dev, PTR_ERR(gphy->sw),
+ "failed to register typec switch\n");
+
+ return 0;
+}
+
+static void google_usb_phy_remove(struct platform_device *pdev)
+{
+ struct google_usb_phy *gphy = dev_get_drvdata(&pdev->dev);
+
+ typec_switch_unregister(gphy->sw);
+ pm_runtime_disable(&pdev->dev);
+}
+
+static const struct of_device_id google_usb_phy_of_match[] = {
+ {
+ .compatible = "google,lga-usb-phy",
+ },
+ { }
+};
+MODULE_DEVICE_TABLE(of, google_usb_phy_of_match);
+
+static struct platform_driver google_usb_phy = {
+ .probe = google_usb_phy_probe,
+ .remove = google_usb_phy_remove,
+ .driver = {
+ .name = "google-usb-phy",
+ .of_match_table = google_usb_phy_of_match,
+ }
+};
+
+module_platform_driver(google_usb_phy);
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Google USB phy driver");