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authorLinus Torvalds <torvalds@linux-foundation.org>2026-09-13 12:27:00 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-09-13 12:27:00 -0700
commit22098763a10d9c1340827fcf6edab66f153b27f0 (patch)
tree3962f95a34df034652ff93686cdd156c7197f2d9 /drivers/input/touchscreen/sun4i-ts.c
downloadlinux-stable-22098763a10d9c1340827fcf6edab66f153b27f0.tar.gz
linux-stable-22098763a10d9c1340827fcf6edab66f153b27f0.zip
Merge tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted
Pull tracing fixes from Steven Rostedt: - Don't destroy user event fields when removal fails User event fields are destroyed before the event is removed from visibility. But that can fail leaving the still visible event with no fields. Move the destroying of the fields to after the event is successfully removed from visibility. - Initialize function graph state is fork before calling copy_exec_state() For non-CLONE_VM forks, copy_exec_state() allocates a new task_exec_state. If that allocation fails, ftrace_graph_exit_task() will free the tasks ret_stack pointer. Since that pointer is still using the parent's ret_stack, it mistakenly frees the parent's pointer too. Call ftrace_graph_init() on the task first which will NULL out the new tasks's ret_stack and if the copy fails, it will not free anything. - Remove FGRAPH_MAX_INDEX The macro FGRAPH_MAX_INDEX was added but never used. Remove it. - Save ent_size in function graph printing of nested functions The function graph tracer needs to look at the next event to see if the next event is the return of the current function entry. If it is, it prints a single line: ktime_get(); Otherwise it prints it like a nested function: tick_nohz_irq_exit() { ktime_get(); kcpustat_irq_exit(); } In order to look at the next event, it must save the current event so that it has the information to print from it. It saves the event in the iterator descriptor called "ent". What it doesn't save is the ent_size of the event which is now used to know if the function graph arguments are to be printed. The peek doesn't save the size so the size used happens to be that of the size of the last event that was seen. Save the entry event size in the iterator descriptor so that the correct size is used. - Fix several errors with freeing data in the histogram code The histogram code had a lot of leaked or or incorrect accounting when failures happen. Correct them. - Fix histogram regression of .percent and .graph modifiers Up until 6.3 histogram values could have "percent" or "graph" modifiers that changed how they were printed. But a change that added restricting histograms values from being strings, stack traces and other modifiers inadvertently prevented them from using the percent and graph modifiers, which were legal use cases for values. Put back the percent and graph modifiers. - Fix various typos in the comments - Set the trace_clock before initializing a histogram with clock argument The histogram API allows the user to specific which trace clock to use via a "clock=" string. The histogram is set up first before the clock is checked. If the passed in clock is not valid, it exits without fully fixing up the histogram leaving it on the list and a use-after-free can trigger. Update the clock argument first and if it fails then exit gracefully before the histogram trigger is placed on any lists. - Restore :mod: trailer after parsing in ftrace_set_clr_event The function ftrace_set_clr_event() modifies the parse string and needs to put it back to what was passed in. It searches for ":mod:" via a strsep() but fails to put back the first ':' in the string. Add back the ':' in the passed in string. - Take trace_array reference when opening a tracer options file The options files are dynamically created and some tracers add their own options. When a tracer adds their own list of options, the trace_array holding them has an array to hold the list of options for each tracer. This array increases in size via a krealloc(), and the new entry gets a newly allocated array to hold the options of the new tracer being added. The element in each entry of the tracer's option array holds a pointer back to the trace_array, a pointer to the tracer it is associated to, a pointer to the flags of the option. The issue is that these arrays are freed when the trace_array is freed when its instance it represents is removed from the instances directory. There's a race that an open of one of these options files can happen when the instance is being removed. Add a new helper function to be called by the open function of the options file to iterate all existing trace_arrays under a lock and find the one that has the given option element in one of it's tracer arrays. If found, then update the associated trace_array's reference counter to keep it from being freed. If not found, have the open call return -ENODEV. - Disable interrupts when acquiring the lock in rb_wake_up_waiters() The function rb_wake_up_waiters() assumes it will be called in interrupt context and does not disable irqs when taking cpu_buffer->reader_lock, which can be called in hard interrupt context. The issue is in PREEMPT_RT, this function is called in thread context leaving this lock open to a deadlock. Take the lock with interrupts disabled. - Use rcu_assign_pointer() for tmp_ops filter hash The tmp_ops used in update_ftrace_direct_mod() assigns its filter_hash field directly, but that field is annotated as __rcu and sparse complains. Assign it with rcu_assign_pointer() - Fix use-after-free in enable_trigger_private_data_free() The trace_event_call is accessed through the event_trigger_data's trace_event_file pointer to put the trace_event_call on freeing. The issue is that the trace_event_file data may have been freed already causing a use-after-free. Add a field to the event_trigger_data that points directly to the trace_event_call so that it can decrement its reference directly without needing to go through the trace_event_file. - Fix accounting of buffer data remote headers trace_buffer_desc_size() and trace_remote_alloc_buffer() undercount the number of pages is needed for the asked for size as it doesn't take into account the meta data on each page. Add a helper function to do the calculation properly and use that in these functions. - Catch nr_page_va overflow in ring_buffer_desc sizing The number of pages per remote ring buffer is capped by ring_buffer_desc::nr_page_va (32 bits). A buffer_size large enough to overflow that field would silently allocate a descriptor smaller than what was asked for. - Do not resize the subbuf order if any per_cpu buffer is disabled The mmapping of ring buffers disables resizing the subbuffers, but it is done per-cpu whereas the subbuf size change is done for all the per_cpu buffers under the buffer->mutex. It could change the size of some while the mapping is happening on others. Have the resize of the subbuf order check all the per_cpu buffers under the lock to see if any of them is disabled before starting and causing an inconsistency between buffers that are being mapped. * tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (25 commits) ring-buffer: Check resize_disabled before publishing the new subbuf order tracing/remotes: Catch nr_page_va overflow in ring_buffer_desc sizing tracing/remotes: Account for ring buffer page header in size calculation tracing: Don't dereference trace_event_file in deferred trigger free ftrace: Use rcu_assign_pointer() for tmp_ops filter hash ring-buffer: Acquire the lock with irqsave in rb_wake_up_waiters() tracing: Take trace_array reference when opening a tracer options file tracing: Fix ring_buffer_read_page_size() kernel-doc tracing: Restore :mod: trailer after parsing in ftrace_set_clr_event() tracing: Fix memory corruption from a "STACKTRACE" histogram key tracing: Fix memory corruption from the histogram stacktrace modifier tracing: Undo the registration when enabling the histogram trigger fails tracing: Take the reference before publishing the named histogram trigger tracing: Set the trace clock before registering the histogram trigger tracing: Fix typo "preceeded" in comment tracing: Fix typo "availabe" in comment tracing: Let histogram values keep the percent and graph modifiers tracing: Keep the entry count when the histogram stats allocation fails tracing: Free histogram the field rejected for a bad modifier tracing: Free histogram the var ref when its initialization fails ...
Diffstat (limited to 'drivers/input/touchscreen/sun4i-ts.c')
-rw-r--r--drivers/input/touchscreen/sun4i-ts.c411
1 files changed, 411 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/sun4i-ts.c b/drivers/input/touchscreen/sun4i-ts.c
new file mode 100644
index 000000000..e82860600
--- /dev/null
+++ b/drivers/input/touchscreen/sun4i-ts.c
@@ -0,0 +1,411 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Allwinner sunxi resistive touchscreen controller driver
+ *
+ * Copyright (C) 2013 - 2014 Hans de Goede <hdegoede@redhat.com>
+ *
+ * The hwmon parts are based on work by Corentin LABBE which is:
+ * Copyright (C) 2013 Corentin LABBE <clabbe.montjoie@gmail.com>
+ */
+
+/*
+ * The sun4i-ts controller is capable of detecting a second touch, but when a
+ * second touch is present then the accuracy becomes so bad the reported touch
+ * location is not useable.
+ *
+ * The original android driver contains some complicated heuristics using the
+ * aprox. distance between the 2 touches to see if the user is making a pinch
+ * open / close movement, and then reports emulated multi-touch events around
+ * the last touch coordinate (as the dual-touch coordinates are worthless).
+ *
+ * These kinds of heuristics are just asking for trouble (and don't belong
+ * in the kernel). So this driver offers straight forward, reliable single
+ * touch functionality only.
+ *
+ * s.a. A20 User Manual "1.15 TP" (Documentation/arch/arm/sunxi.rst)
+ * (looks like the description in the A20 User Manual v1.3 is better
+ * than the one in the A10 User Manual v.1.5)
+ */
+
+#include <linux/err.h>
+#include <linux/hwmon.h>
+#include <linux/thermal.h>
+#include <linux/init.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#define TP_CTRL0 0x00
+#define TP_CTRL1 0x04
+#define TP_CTRL2 0x08
+#define TP_CTRL3 0x0c
+#define TP_INT_FIFOC 0x10
+#define TP_INT_FIFOS 0x14
+#define TP_TPR 0x18
+#define TP_CDAT 0x1c
+#define TEMP_DATA 0x20
+#define TP_DATA 0x24
+
+/* TP_CTRL0 bits */
+#define ADC_FIRST_DLY(x) ((x) << 24) /* 8 bits */
+#define ADC_FIRST_DLY_MODE(x) ((x) << 23)
+#define ADC_CLK_SEL(x) ((x) << 22)
+#define ADC_CLK_DIV(x) ((x) << 20) /* 3 bits */
+#define FS_DIV(x) ((x) << 16) /* 4 bits */
+#define T_ACQ(x) ((x) << 0) /* 16 bits */
+
+/* TP_CTRL1 bits */
+#define STYLUS_UP_DEBOUN(x) ((x) << 12) /* 8 bits */
+#define STYLUS_UP_DEBOUN_EN(x) ((x) << 9)
+#define TOUCH_PAN_CALI_EN(x) ((x) << 6)
+#define TP_DUAL_EN(x) ((x) << 5)
+#define TP_MODE_EN(x) ((x) << 4)
+#define TP_ADC_SELECT(x) ((x) << 3)
+#define ADC_CHAN_SELECT(x) ((x) << 0) /* 3 bits */
+
+/* on sun6i, bits 3~6 are left shifted by 1 to 4~7 */
+#define SUN6I_TP_MODE_EN(x) ((x) << 5)
+
+/* TP_CTRL2 bits */
+#define TP_SENSITIVE_ADJUST(x) ((x) << 28) /* 4 bits */
+#define TP_MODE_SELECT(x) ((x) << 26) /* 2 bits */
+#define PRE_MEA_EN(x) ((x) << 24)
+#define PRE_MEA_THRE_CNT(x) ((x) << 0) /* 24 bits */
+
+/* TP_CTRL3 bits */
+#define FILTER_EN(x) ((x) << 2)
+#define FILTER_TYPE(x) ((x) << 0) /* 2 bits */
+
+/* TP_INT_FIFOC irq and fifo mask / control bits */
+#define TEMP_IRQ_EN(x) ((x) << 18)
+#define OVERRUN_IRQ_EN(x) ((x) << 17)
+#define DATA_IRQ_EN(x) ((x) << 16)
+#define TP_DATA_XY_CHANGE(x) ((x) << 13)
+#define FIFO_TRIG(x) ((x) << 8) /* 5 bits */
+#define DATA_DRQ_EN(x) ((x) << 7)
+#define FIFO_FLUSH(x) ((x) << 4)
+#define TP_UP_IRQ_EN(x) ((x) << 1)
+#define TP_DOWN_IRQ_EN(x) ((x) << 0)
+
+/* TP_INT_FIFOS irq and fifo status bits */
+#define TEMP_DATA_PENDING BIT(18)
+#define FIFO_OVERRUN_PENDING BIT(17)
+#define FIFO_DATA_PENDING BIT(16)
+#define TP_IDLE_FLG BIT(2)
+#define TP_UP_PENDING BIT(1)
+#define TP_DOWN_PENDING BIT(0)
+
+/* TP_TPR bits */
+#define TEMP_ENABLE(x) ((x) << 16)
+#define TEMP_PERIOD(x) ((x) << 0) /* t = x * 256 * 16 / clkin */
+
+struct sun4i_ts_data {
+ struct device *dev;
+ struct input_dev *input;
+ void __iomem *base;
+ unsigned int irq;
+ bool ignore_fifo_data;
+ int temp_data;
+ int temp_offset;
+ int temp_step;
+};
+
+static void sun4i_ts_irq_handle_input(struct sun4i_ts_data *ts, u32 reg_val)
+{
+ u32 x, y;
+
+ if (reg_val & FIFO_DATA_PENDING) {
+ x = readl(ts->base + TP_DATA);
+ y = readl(ts->base + TP_DATA);
+ /* The 1st location reported after an up event is unreliable */
+ if (!ts->ignore_fifo_data) {
+ input_report_abs(ts->input, ABS_X, x);
+ input_report_abs(ts->input, ABS_Y, y);
+ /*
+ * The hardware has a separate down status bit, but
+ * that gets set before we get the first location,
+ * resulting in reporting a click on the old location.
+ */
+ input_report_key(ts->input, BTN_TOUCH, 1);
+ input_sync(ts->input);
+ } else {
+ ts->ignore_fifo_data = false;
+ }
+ }
+
+ if (reg_val & TP_UP_PENDING) {
+ ts->ignore_fifo_data = true;
+ input_report_key(ts->input, BTN_TOUCH, 0);
+ input_sync(ts->input);
+ }
+}
+
+static irqreturn_t sun4i_ts_irq(int irq, void *dev_id)
+{
+ struct sun4i_ts_data *ts = dev_id;
+ u32 reg_val;
+
+ reg_val = readl(ts->base + TP_INT_FIFOS);
+
+ if (reg_val & TEMP_DATA_PENDING)
+ ts->temp_data = readl(ts->base + TEMP_DATA);
+
+ if (ts->input)
+ sun4i_ts_irq_handle_input(ts, reg_val);
+
+ writel(reg_val, ts->base + TP_INT_FIFOS);
+
+ return IRQ_HANDLED;
+}
+
+static int sun4i_ts_open(struct input_dev *dev)
+{
+ struct sun4i_ts_data *ts = input_get_drvdata(dev);
+
+ /* Flush, set trig level to 1, enable temp, data and up irqs */
+ writel(TEMP_IRQ_EN(1) | DATA_IRQ_EN(1) | FIFO_TRIG(1) | FIFO_FLUSH(1) |
+ TP_UP_IRQ_EN(1), ts->base + TP_INT_FIFOC);
+
+ return 0;
+}
+
+static void sun4i_ts_close(struct input_dev *dev)
+{
+ struct sun4i_ts_data *ts = input_get_drvdata(dev);
+
+ /* Deactivate all input IRQs */
+ writel(TEMP_IRQ_EN(1), ts->base + TP_INT_FIFOC);
+}
+
+static int sun4i_get_temp(const struct sun4i_ts_data *ts, int *temp)
+{
+ /* No temp_data until the first irq */
+ if (ts->temp_data == -1)
+ return -EAGAIN;
+
+ *temp = ts->temp_data * ts->temp_step - ts->temp_offset;
+
+ return 0;
+}
+
+static int sun4i_get_tz_temp(struct thermal_zone_device *tz, int *temp)
+{
+ return sun4i_get_temp(thermal_zone_device_priv(tz), temp);
+}
+
+static const struct thermal_zone_device_ops sun4i_ts_tz_ops = {
+ .get_temp = sun4i_get_tz_temp,
+};
+
+static ssize_t show_temp(struct device *dev, struct device_attribute *devattr,
+ char *buf)
+{
+ struct sun4i_ts_data *ts = dev_get_drvdata(dev);
+ int temp;
+ int error;
+
+ error = sun4i_get_temp(ts, &temp);
+ if (error)
+ return error;
+
+ return sprintf(buf, "%d\n", temp);
+}
+
+static ssize_t show_temp_label(struct device *dev,
+ struct device_attribute *devattr, char *buf)
+{
+ return sprintf(buf, "SoC temperature\n");
+}
+
+static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL);
+static DEVICE_ATTR(temp1_label, S_IRUGO, show_temp_label, NULL);
+
+static struct attribute *sun4i_ts_attrs[] = {
+ &dev_attr_temp1_input.attr,
+ &dev_attr_temp1_label.attr,
+ NULL
+};
+ATTRIBUTE_GROUPS(sun4i_ts);
+
+static int sun4i_ts_probe(struct platform_device *pdev)
+{
+ struct sun4i_ts_data *ts;
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ struct device *hwmon;
+ struct thermal_zone_device *thermal;
+ int error;
+ u32 reg;
+ bool ts_attached;
+ u32 tp_sensitive_adjust = 15;
+ u32 filter_type = 1;
+
+ ts = devm_kzalloc(dev, sizeof(struct sun4i_ts_data), GFP_KERNEL);
+ if (!ts)
+ return -ENOMEM;
+
+ ts->dev = dev;
+ ts->ignore_fifo_data = true;
+ ts->temp_data = -1;
+ if (of_device_is_compatible(np, "allwinner,sun6i-a31-ts")) {
+ /* Allwinner SDK has temperature (C) = (value / 6) - 271 */
+ ts->temp_offset = 271000;
+ ts->temp_step = 167;
+ } else if (of_device_is_compatible(np, "allwinner,sun4i-a10-ts")) {
+ /*
+ * The A10 temperature sensor has quite a wide spread, these
+ * parameters are based on the averaging of the calibration
+ * results of 4 completely different boards, with a spread of
+ * temp_step from 0.096 - 0.170 and temp_offset from 176 - 331.
+ */
+ ts->temp_offset = 257000;
+ ts->temp_step = 133;
+ } else {
+ /*
+ * The user manuals do not contain the formula for calculating
+ * the temperature. The formula used here is from the AXP209,
+ * which is designed by X-Powers, an affiliate of Allwinner:
+ *
+ * temperature (C) = (value * 0.1) - 144.7
+ *
+ * Allwinner does not have any documentation whatsoever for
+ * this hardware. Moreover, it is claimed that the sensor
+ * is inaccurate and cannot work properly.
+ */
+ ts->temp_offset = 144700;
+ ts->temp_step = 100;
+ }
+
+ ts_attached = of_property_read_bool(np, "allwinner,ts-attached");
+ if (ts_attached) {
+ ts->input = devm_input_allocate_device(dev);
+ if (!ts->input)
+ return -ENOMEM;
+
+ ts->input->name = pdev->name;
+ ts->input->phys = "sun4i_ts/input0";
+ ts->input->open = sun4i_ts_open;
+ ts->input->close = sun4i_ts_close;
+ ts->input->id.bustype = BUS_HOST;
+ ts->input->id.vendor = 0x0001;
+ ts->input->id.product = 0x0001;
+ ts->input->id.version = 0x0100;
+ ts->input->evbit[0] = BIT(EV_SYN) | BIT(EV_KEY) | BIT(EV_ABS);
+ __set_bit(BTN_TOUCH, ts->input->keybit);
+ input_set_abs_params(ts->input, ABS_X, 0, 4095, 0, 0);
+ input_set_abs_params(ts->input, ABS_Y, 0, 4095, 0, 0);
+ input_set_drvdata(ts->input, ts);
+ }
+
+ ts->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(ts->base))
+ return PTR_ERR(ts->base);
+
+ ts->irq = platform_get_irq(pdev, 0);
+ error = devm_request_irq(dev, ts->irq, sun4i_ts_irq, 0, "sun4i-ts", ts);
+ if (error)
+ return error;
+
+ /*
+ * Select HOSC clk, clkin = clk / 6, adc samplefreq = clkin / 8192,
+ * t_acq = clkin / (16 * 64)
+ */
+ writel(ADC_CLK_SEL(0) | ADC_CLK_DIV(2) | FS_DIV(7) | T_ACQ(63),
+ ts->base + TP_CTRL0);
+
+ /*
+ * tp_sensitive_adjust is an optional property
+ * tp_mode = 0 : only x and y coordinates, as we don't use dual touch
+ */
+ of_property_read_u32(np, "allwinner,tp-sensitive-adjust",
+ &tp_sensitive_adjust);
+ writel(TP_SENSITIVE_ADJUST(tp_sensitive_adjust) | TP_MODE_SELECT(0),
+ ts->base + TP_CTRL2);
+
+ /*
+ * Enable median and averaging filter, optional property for
+ * filter type.
+ */
+ of_property_read_u32(np, "allwinner,filter-type", &filter_type);
+ writel(FILTER_EN(1) | FILTER_TYPE(filter_type), ts->base + TP_CTRL3);
+
+ /* Enable temperature measurement, period 1953 (2 seconds) */
+ writel(TEMP_ENABLE(1) | TEMP_PERIOD(1953), ts->base + TP_TPR);
+
+ /*
+ * Set stylus up debounce to aprox 10 ms, enable debounce, and
+ * finally enable tp mode.
+ */
+ reg = STYLUS_UP_DEBOUN(5) | STYLUS_UP_DEBOUN_EN(1);
+ if (of_device_is_compatible(np, "allwinner,sun6i-a31-ts"))
+ reg |= SUN6I_TP_MODE_EN(1);
+ else
+ reg |= TP_MODE_EN(1);
+ writel(reg, ts->base + TP_CTRL1);
+
+ /*
+ * The thermal core does not register hwmon devices for DT-based
+ * thermal zone sensors, such as this one.
+ */
+ hwmon = devm_hwmon_device_register_with_groups(ts->dev, "sun4i_ts",
+ ts, sun4i_ts_groups);
+ if (IS_ERR(hwmon))
+ return PTR_ERR(hwmon);
+
+ thermal = devm_thermal_of_zone_register(ts->dev, 0, ts,
+ &sun4i_ts_tz_ops);
+ if (IS_ERR(thermal))
+ return PTR_ERR(thermal);
+
+ writel(TEMP_IRQ_EN(1), ts->base + TP_INT_FIFOC);
+
+ if (ts_attached) {
+ error = input_register_device(ts->input);
+ if (error) {
+ writel(0, ts->base + TP_INT_FIFOC);
+ return error;
+ }
+ }
+
+ platform_set_drvdata(pdev, ts);
+ return 0;
+}
+
+static void sun4i_ts_remove(struct platform_device *pdev)
+{
+ struct sun4i_ts_data *ts = platform_get_drvdata(pdev);
+
+ /* Explicit unregister to avoid open/close changing the imask later */
+ if (ts->input)
+ input_unregister_device(ts->input);
+
+ /* Deactivate all IRQs */
+ writel(0, ts->base + TP_INT_FIFOC);
+}
+
+static const struct of_device_id sun4i_ts_of_match[] = {
+ { .compatible = "allwinner,sun4i-a10-ts", },
+ { .compatible = "allwinner,sun5i-a13-ts", },
+ { .compatible = "allwinner,sun6i-a31-ts", },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, sun4i_ts_of_match);
+
+static struct platform_driver sun4i_ts_driver = {
+ .driver = {
+ .name = "sun4i-ts",
+ .of_match_table = sun4i_ts_of_match,
+ },
+ .probe = sun4i_ts_probe,
+ .remove = sun4i_ts_remove,
+};
+
+module_platform_driver(sun4i_ts_driver);
+
+MODULE_DESCRIPTION("Allwinner sun4i resistive touchscreen controller driver");
+MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
+MODULE_LICENSE("GPL");