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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /drivers/input/touchscreen/stmpe-ts.c
downloadlinux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz
linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
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 ...
Diffstat (limited to 'drivers/input/touchscreen/stmpe-ts.c')
-rw-r--r--drivers/input/touchscreen/stmpe-ts.c372
1 files changed, 372 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/stmpe-ts.c b/drivers/input/touchscreen/stmpe-ts.c
new file mode 100644
index 000000000..af0fb38bc
--- /dev/null
+++ b/drivers/input/touchscreen/stmpe-ts.c
@@ -0,0 +1,372 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * STMicroelectronics STMPE811 Touchscreen Driver
+ *
+ * (C) 2010 Luotao Fu <l.fu@pengutronix.de>
+ * All rights reserved.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/interrupt.h>
+#include <linux/device.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/input.h>
+#include <linux/input/touchscreen.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/workqueue.h>
+
+#include <linux/mfd/stmpe.h>
+
+/* Register layouts and functionalities are identical on all stmpexxx variants
+ * with touchscreen controller
+ */
+#define STMPE_REG_INT_STA 0x0B
+#define STMPE_REG_TSC_CTRL 0x40
+#define STMPE_REG_TSC_CFG 0x41
+#define STMPE_REG_FIFO_TH 0x4A
+#define STMPE_REG_FIFO_STA 0x4B
+#define STMPE_REG_FIFO_SIZE 0x4C
+#define STMPE_REG_TSC_DATA_XYZ 0x52
+#define STMPE_REG_TSC_FRACTION_Z 0x56
+#define STMPE_REG_TSC_I_DRIVE 0x58
+
+#define OP_MOD_XYZ 0
+
+#define STMPE_TSC_CTRL_TSC_EN (1<<0)
+
+#define STMPE_FIFO_STA_RESET (1<<0)
+
+#define STMPE_IRQ_TOUCH_DET 0
+
+#define STMPE_TS_NAME "stmpe-ts"
+#define XY_MASK 0xfff
+
+/**
+ * struct stmpe_touch - stmpe811 touch screen controller state
+ * @stmpe: pointer back to STMPE MFD container
+ * @idev: registered input device
+ * @work: a work item used to scan the device
+ * @dev: a pointer back to the MFD cell struct device*
+ * @prop: Touchscreen properties
+ * @ave_ctrl: Sample average control
+ * (0 -> 1 sample, 1 -> 2 samples, 2 -> 4 samples, 3 -> 8 samples)
+ * @touch_det_delay: Touch detect interrupt delay
+ * (0 -> 10 us, 1 -> 50 us, 2 -> 100 us, 3 -> 500 us,
+ * 4-> 1 ms, 5 -> 5 ms, 6 -> 10 ms, 7 -> 50 ms)
+ * recommended is 3
+ * @settling: Panel driver settling time
+ * (0 -> 10 us, 1 -> 100 us, 2 -> 500 us, 3 -> 1 ms,
+ * 4 -> 5 ms, 5 -> 10 ms, 6 for 50 ms, 7 -> 100 ms)
+ * recommended is 2
+ * @fraction_z: Length of the fractional part in z
+ * (fraction_z ([0..7]) = Count of the fractional part)
+ * recommended is 7
+ * @i_drive: current limit value of the touchscreen drivers
+ * (0 -> 20 mA typical 35 mA max, 1 -> 50 mA typical 80 mA max)
+ */
+struct stmpe_touch {
+ struct stmpe *stmpe;
+ struct input_dev *idev;
+ struct delayed_work work;
+ struct device *dev;
+ struct touchscreen_properties prop;
+ u8 ave_ctrl;
+ u8 touch_det_delay;
+ u8 settling;
+ u8 fraction_z;
+ u8 i_drive;
+};
+
+static int __stmpe_reset_fifo(struct stmpe *stmpe)
+{
+ int ret;
+
+ ret = stmpe_set_bits(stmpe, STMPE_REG_FIFO_STA,
+ STMPE_FIFO_STA_RESET, STMPE_FIFO_STA_RESET);
+ if (ret)
+ return ret;
+
+ return stmpe_set_bits(stmpe, STMPE_REG_FIFO_STA,
+ STMPE_FIFO_STA_RESET, 0);
+}
+
+static void stmpe_work(struct work_struct *work)
+{
+ int int_sta;
+ u32 timeout = 40;
+
+ struct stmpe_touch *ts =
+ container_of(work, struct stmpe_touch, work.work);
+
+ int_sta = stmpe_reg_read(ts->stmpe, STMPE_REG_INT_STA);
+
+ /*
+ * touch_det sometimes get desasserted or just get stuck. This appears
+ * to be a silicon bug, We still have to clarify this with the
+ * manufacture. As a workaround We release the key anyway if the
+ * touch_det keeps coming in after 4ms, while the FIFO contains no value
+ * during the whole time.
+ */
+ while ((int_sta & (1 << STMPE_IRQ_TOUCH_DET)) && (timeout > 0)) {
+ timeout--;
+ int_sta = stmpe_reg_read(ts->stmpe, STMPE_REG_INT_STA);
+ udelay(100);
+ }
+
+ /* reset the FIFO before we report release event */
+ __stmpe_reset_fifo(ts->stmpe);
+
+ input_report_abs(ts->idev, ABS_PRESSURE, 0);
+ input_report_key(ts->idev, BTN_TOUCH, 0);
+ input_sync(ts->idev);
+}
+
+static irqreturn_t stmpe_ts_handler(int irq, void *data)
+{
+ u8 data_set[4];
+ int x, y, z;
+ struct stmpe_touch *ts = data;
+
+ /*
+ * Cancel scheduled polling for release if we have new value
+ * available. Wait if the polling is already running.
+ */
+ cancel_delayed_work_sync(&ts->work);
+
+ /*
+ * The FIFO sometimes just crashes and stops generating interrupts. This
+ * appears to be a silicon bug. We still have to clarify this with
+ * the manufacture. As a workaround we disable the TSC while we are
+ * collecting data and flush the FIFO after reading
+ */
+ stmpe_set_bits(ts->stmpe, STMPE_REG_TSC_CTRL,
+ STMPE_TSC_CTRL_TSC_EN, 0);
+
+ stmpe_block_read(ts->stmpe, STMPE_REG_TSC_DATA_XYZ, 4, data_set);
+
+ x = (data_set[0] << 4) | (data_set[1] >> 4);
+ y = ((data_set[1] & 0xf) << 8) | data_set[2];
+ z = data_set[3];
+
+ touchscreen_report_pos(ts->idev, &ts->prop, x, y, false);
+ input_report_abs(ts->idev, ABS_PRESSURE, z);
+ input_report_key(ts->idev, BTN_TOUCH, 1);
+ input_sync(ts->idev);
+
+ /* flush the FIFO after we have read out our values. */
+ __stmpe_reset_fifo(ts->stmpe);
+
+ /* reenable the tsc */
+ stmpe_set_bits(ts->stmpe, STMPE_REG_TSC_CTRL,
+ STMPE_TSC_CTRL_TSC_EN, STMPE_TSC_CTRL_TSC_EN);
+
+ /* start polling for touch_det to detect release */
+ schedule_delayed_work(&ts->work, msecs_to_jiffies(50));
+
+ return IRQ_HANDLED;
+}
+
+static int stmpe_init_hw(struct stmpe_touch *ts)
+{
+ int ret;
+ u8 tsc_cfg, tsc_cfg_mask;
+ struct stmpe *stmpe = ts->stmpe;
+ struct device *dev = ts->dev;
+
+ ret = stmpe_enable(stmpe, STMPE_BLOCK_TOUCHSCREEN | STMPE_BLOCK_ADC);
+ if (ret) {
+ dev_err(dev, "Could not enable clock for ADC and TS\n");
+ return ret;
+ }
+
+ ret = stmpe811_adc_common_init(stmpe);
+ if (ret) {
+ stmpe_disable(stmpe, STMPE_BLOCK_TOUCHSCREEN | STMPE_BLOCK_ADC);
+ return ret;
+ }
+
+ tsc_cfg = STMPE_AVE_CTRL(ts->ave_ctrl) |
+ STMPE_DET_DELAY(ts->touch_det_delay) |
+ STMPE_SETTLING(ts->settling);
+ tsc_cfg_mask = STMPE_AVE_CTRL(0xff) | STMPE_DET_DELAY(0xff) |
+ STMPE_SETTLING(0xff);
+
+ ret = stmpe_set_bits(stmpe, STMPE_REG_TSC_CFG, tsc_cfg_mask, tsc_cfg);
+ if (ret) {
+ dev_err(dev, "Could not config touch\n");
+ return ret;
+ }
+
+ ret = stmpe_set_bits(stmpe, STMPE_REG_TSC_FRACTION_Z,
+ STMPE_FRACTION_Z(0xff), STMPE_FRACTION_Z(ts->fraction_z));
+ if (ret) {
+ dev_err(dev, "Could not config touch\n");
+ return ret;
+ }
+
+ ret = stmpe_set_bits(stmpe, STMPE_REG_TSC_I_DRIVE,
+ STMPE_I_DRIVE(0xff), STMPE_I_DRIVE(ts->i_drive));
+ if (ret) {
+ dev_err(dev, "Could not config touch\n");
+ return ret;
+ }
+
+ /* set FIFO to 1 for single point reading */
+ ret = stmpe_reg_write(stmpe, STMPE_REG_FIFO_TH, 1);
+ if (ret) {
+ dev_err(dev, "Could not set FIFO\n");
+ return ret;
+ }
+
+ ret = stmpe_set_bits(stmpe, STMPE_REG_TSC_CTRL,
+ STMPE_OP_MODE(0xff), STMPE_OP_MODE(OP_MOD_XYZ));
+ if (ret) {
+ dev_err(dev, "Could not set mode\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static int stmpe_ts_open(struct input_dev *dev)
+{
+ struct stmpe_touch *ts = input_get_drvdata(dev);
+ int ret = 0;
+
+ ret = __stmpe_reset_fifo(ts->stmpe);
+ if (ret)
+ return ret;
+
+ return stmpe_set_bits(ts->stmpe, STMPE_REG_TSC_CTRL,
+ STMPE_TSC_CTRL_TSC_EN, STMPE_TSC_CTRL_TSC_EN);
+}
+
+static void stmpe_ts_close(struct input_dev *dev)
+{
+ struct stmpe_touch *ts = input_get_drvdata(dev);
+
+ cancel_delayed_work_sync(&ts->work);
+
+ stmpe_set_bits(ts->stmpe, STMPE_REG_TSC_CTRL,
+ STMPE_TSC_CTRL_TSC_EN, 0);
+}
+
+static void stmpe_ts_get_platform_info(struct platform_device *pdev,
+ struct stmpe_touch *ts)
+{
+ struct device_node *np = pdev->dev.of_node;
+ u32 val;
+
+ if (np) {
+ if (!of_property_read_u32(np, "st,sample-time", &val))
+ ts->stmpe->sample_time = val;
+ if (!of_property_read_u32(np, "st,mod-12b", &val))
+ ts->stmpe->mod_12b = val;
+ if (!of_property_read_u32(np, "st,ref-sel", &val))
+ ts->stmpe->ref_sel = val;
+ if (!of_property_read_u32(np, "st,adc-freq", &val))
+ ts->stmpe->adc_freq = val;
+ if (!of_property_read_u32(np, "st,ave-ctrl", &val))
+ ts->ave_ctrl = val;
+ if (!of_property_read_u32(np, "st,touch-det-delay", &val))
+ ts->touch_det_delay = val;
+ if (!of_property_read_u32(np, "st,settling", &val))
+ ts->settling = val;
+ if (!of_property_read_u32(np, "st,fraction-z", &val))
+ ts->fraction_z = val;
+ if (!of_property_read_u32(np, "st,i-drive", &val))
+ ts->i_drive = val;
+ }
+}
+
+static int stmpe_input_probe(struct platform_device *pdev)
+{
+ struct stmpe *stmpe = dev_get_drvdata(pdev->dev.parent);
+ struct stmpe_touch *ts;
+ struct input_dev *idev;
+ int error;
+ int ts_irq;
+
+ ts_irq = platform_get_irq_byname(pdev, "FIFO_TH");
+ if (ts_irq < 0)
+ return ts_irq;
+
+ ts = devm_kzalloc(&pdev->dev, sizeof(*ts), GFP_KERNEL);
+ if (!ts)
+ return -ENOMEM;
+
+ idev = devm_input_allocate_device(&pdev->dev);
+ if (!idev)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, ts);
+ ts->stmpe = stmpe;
+ ts->idev = idev;
+ ts->dev = &pdev->dev;
+
+ stmpe_ts_get_platform_info(pdev, ts);
+
+ INIT_DELAYED_WORK(&ts->work, stmpe_work);
+
+ error = devm_request_threaded_irq(&pdev->dev, ts_irq,
+ NULL, stmpe_ts_handler,
+ IRQF_ONESHOT, STMPE_TS_NAME, ts);
+ if (error) {
+ dev_err(&pdev->dev, "Failed to request IRQ %d\n", ts_irq);
+ return error;
+ }
+
+ error = stmpe_init_hw(ts);
+ if (error)
+ return error;
+
+ idev->name = STMPE_TS_NAME;
+ idev->phys = STMPE_TS_NAME"/input0";
+ idev->id.bustype = BUS_I2C;
+
+ idev->open = stmpe_ts_open;
+ idev->close = stmpe_ts_close;
+
+ input_set_drvdata(idev, ts);
+
+ input_set_capability(idev, EV_KEY, BTN_TOUCH);
+ input_set_abs_params(idev, ABS_X, 0, XY_MASK, 0, 0);
+ input_set_abs_params(idev, ABS_Y, 0, XY_MASK, 0, 0);
+ input_set_abs_params(idev, ABS_PRESSURE, 0x0, 0xff, 0, 0);
+
+ touchscreen_parse_properties(idev, false, &ts->prop);
+
+ error = input_register_device(idev);
+ if (error) {
+ dev_err(&pdev->dev, "Could not register input device\n");
+ return error;
+ }
+
+ return 0;
+}
+
+static void stmpe_ts_remove(struct platform_device *pdev)
+{
+ struct stmpe_touch *ts = platform_get_drvdata(pdev);
+
+ stmpe_disable(ts->stmpe, STMPE_BLOCK_TOUCHSCREEN);
+}
+
+static struct platform_driver stmpe_ts_driver = {
+ .driver = {
+ .name = STMPE_TS_NAME,
+ },
+ .probe = stmpe_input_probe,
+ .remove = stmpe_ts_remove,
+};
+module_platform_driver(stmpe_ts_driver);
+
+MODULE_ALIAS("platform:stmpe-ts");
+MODULE_AUTHOR("Luotao Fu <l.fu@pengutronix.de>");
+MODULE_DESCRIPTION("STMPEXXX touchscreen driver");
+MODULE_LICENSE("GPL");