From: Sasha Finkelstein <fnkl.kernel@xxxxxxxxx>
Adds a driver for Apple touchscreens using the Z2 protocol.
Signed-off-by: Sasha Finkelstein <fnkl.kernel@xxxxxxxxx>
---
drivers/input/touchscreen/Kconfig | 13 +
drivers/input/touchscreen/Makefile | 1 +
drivers/input/touchscreen/apple_z2.c | 465 +++++++++++++++++++++++++++++++++++
3 files changed, 479 insertions(+)
diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
index 68d99a112e14..76aeea837ab9 100644
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -103,6 +103,19 @@ config TOUCHSCREEN_ADC
To compile this driver as a module, choose M here: the
module will be called resistive-adc-touch.ko.
+config TOUCHSCREEN_APPLE_Z2
+ tristate "Apple Z2 touchscreens"
+ default ARCH_APPLE
+ depends on SPI && INPUT && OF
+ help
+ Say Y here if you have an Apple device with
+ a touchscreen or a touchbar.
+
+ If unsure, say N.
+
+ To compile this driver as a module, choose M here: the
+ module will be called apple_z2.
+
config TOUCHSCREEN_AR1021_I2C
tristate "Microchip AR1020/1021 i2c touchscreen"
depends on I2C && OF
diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile
index 4968c370479a..d885b2c4e3a6 100644
--- a/drivers/input/touchscreen/Makefile
+++ b/drivers/input/touchscreen/Makefile
@@ -15,6 +15,7 @@ obj-$(CONFIG_TOUCHSCREEN_AD7879_I2C) += ad7879-i2c.o
obj-$(CONFIG_TOUCHSCREEN_AD7879_SPI) += ad7879-spi.o
obj-$(CONFIG_TOUCHSCREEN_ADC) += resistive-adc-touch.o
obj-$(CONFIG_TOUCHSCREEN_ADS7846) += ads7846.o
+obj-$(CONFIG_TOUCHSCREEN_APPLE_Z2) += apple_z2.o
obj-$(CONFIG_TOUCHSCREEN_AR1021_I2C) += ar1021_i2c.o
obj-$(CONFIG_TOUCHSCREEN_ATMEL_MXT) += atmel_mxt_ts.o
obj-$(CONFIG_TOUCHSCREEN_AUO_PIXCIR) += auo-pixcir-ts.o
diff --git a/drivers/input/touchscreen/apple_z2.c b/drivers/input/touchscreen/apple_z2.c
new file mode 100644
index 000000000000..06f1d864a137
--- /dev/null
+++ b/drivers/input/touchscreen/apple_z2.c
@@ -0,0 +1,465 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Apple Z2 touchscreen driver
+ *
+ * Copyright (C) The Asahi Linux Contributors
+ */
+
+#include <linux/module.h>
+#include <linux/spi/spi.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/firmware.h>
+#include <linux/input.h>
+#include <linux/input/mt.h>
+
+#define Z2_NUM_FINGERS_OFFSET 16
+#define Z2_FINGERS_OFFSET 24
+#define Z2_TOUCH_STARTED 3
+#define Z2_TOUCH_MOVED 4
+#define Z2_CMD_READ_INTERRUPT_DATA 0xEB
+#define Z2_HBPP_CMD_BLOB 0x3001
+#define Z2_FW_MAGIC 0x5746325A
+#define LOAD_COMMAND_INIT_PAYLOAD 0
+#define LOAD_COMMAND_SEND_BLOB 1
+#define LOAD_COMMAND_SEND_CALIBRATION 2
+
+struct apple_z2 {
+ struct spi_device *spidev;
+ struct gpio_desc *cs_gpio;
+ struct gpio_desc *reset_gpio;
+ struct input_dev *input_dev;
+ struct completion boot_irq;
+ int booted;
+ int counter;
+ int y_size;
+ const char *fw_name;
+ const char *cal_blob;
+ int cal_size;
+};
+
+struct z2_finger {
+ u8 finger;
+ u8 state;
+ __le16 unknown2;
+ __le16 abs_x;
+ __le16 abs_y;
+ __le16 rel_x;
+ __le16 rel_y;
+ __le16 tool_major;
+ __le16 tool_minor;
+ __le16 orientation;
+ __le16 touch_major;
+ __le16 touch_minor;
+ __le16 unused[2];
+ __le16 pressure;
+ __le16 multi;
+} __packed;
+
+struct z2_hbpp_blob_hdr {
+ u16 cmd;
+ u16 len;
+ u32 addr;
+ u16 checksum;
+} __packed;
+
+struct z2_fw_hdr {
+ u32 magic;
+ u32 version;
+} __packed;
+
+struct z2_read_interrupt_cmd {
+ u8 cmd;
+ u8 counter;
+ u8 unused[12];
+ __le16 checksum;
+} __packed;
+
+static void apple_z2_parse_touches(struct apple_z2 *z2, char *msg, size_t msg_len)
+{
+ int i;
+ int nfingers;
+ int slot;
+ int slot_valid;
+ struct z2_finger *fingers;
+
+ if (msg_len <= Z2_NUM_FINGERS_OFFSET)
+ return;
+ nfingers = msg[Z2_NUM_FINGERS_OFFSET];
+ fingers = (struct z2_finger *)(msg + Z2_FINGERS_OFFSET);
+ for (i = 0; i < nfingers; i++) {
+ slot = input_mt_get_slot_by_key(z2->input_dev, fingers[i].finger);
+ if (slot < 0) {
+ dev_warn(&z2->spidev->dev, "unable to get slot for finger");
+ continue;
+ }
+ slot_valid = fingers[i].state == Z2_TOUCH_STARTED ||
+ fingers[i].state == Z2_TOUCH_MOVED;
+ input_mt_slot(z2->input_dev, slot);
+ input_mt_report_slot_state(z2->input_dev, MT_TOOL_FINGER, slot_valid);
+ if (!slot_valid)
+ continue;
+ input_report_abs(z2->input_dev, ABS_MT_POSITION_X,
+ le16_to_cpu(fingers[i].abs_x));
+ input_report_abs(z2->input_dev, ABS_MT_POSITION_Y,
+ z2->y_size - le16_to_cpu(fingers[i].abs_y));
+ input_report_abs(z2->input_dev, ABS_MT_WIDTH_MAJOR,
+ le16_to_cpu(fingers[i].tool_major));
+ input_report_abs(z2->input_dev, ABS_MT_WIDTH_MINOR,
+ le16_to_cpu(fingers[i].tool_minor));
+ input_report_abs(z2->input_dev, ABS_MT_ORIENTATION,
+ le16_to_cpu(fingers[i].orientation));
+ input_report_abs(z2->input_dev, ABS_MT_TOUCH_MAJOR,
+ le16_to_cpu(fingers[i].touch_major));
+ input_report_abs(z2->input_dev, ABS_MT_TOUCH_MINOR,
+ le16_to_cpu(fingers[i].touch_minor));
+ }
+ input_mt_sync_frame(z2->input_dev);
+ input_sync(z2->input_dev);
+}
+
+static int apple_z2_spi_sync(struct apple_z2 *z2, struct spi_message *msg)
+{
+ int err;
+ gpiod_direction_output(z2->cs_gpio, 0);
+ usleep_range(1000, 2000);
+ err = spi_sync(z2->spidev, msg);
+ usleep_range(1000, 2000);
+ gpiod_direction_output(z2->cs_gpio, 1);
+ return err;
+}
+
+static int apple_z2_read_packet(struct apple_z2 *z2)
+{
+ struct spi_message msg;
+ struct spi_transfer xfer;
+ struct z2_read_interrupt_cmd len_cmd;
+ char len_rx[16];
+ size_t pkt_len;
+ char *pkt_rx;
+ int err = 0;
+
+ spi_message_init(&msg);
+ memset(&xfer, 0, sizeof(xfer));
+ memset(&len_cmd, 0, sizeof(len_cmd));
+ len_cmd.cmd = Z2_CMD_READ_INTERRUPT_DATA;
+ len_cmd.counter = z2->counter + 1;
+ len_cmd.checksum = cpu_to_le16(Z2_CMD_READ_INTERRUPT_DATA + 1 + z2->counter);
+ z2->counter = 1 - z2->counter;
+ xfer.tx_buf = &len_cmd;
+ xfer.rx_buf = len_rx;
+ xfer.len = sizeof(len_cmd);
+ spi_message_add_tail(&xfer, &msg);
+ err = apple_z2_spi_sync(z2, &msg);
+ if (err)
+ return err;
+
+ pkt_len = ((len_rx[1] | len_rx[2] << 8) + 8) & (-4);
+ pkt_rx = kzalloc(pkt_len, GFP_KERNEL);
+ if (!pkt_rx)
+ return -ENOMEM;
+
+ spi_message_init(&msg);
+ xfer.rx_buf = pkt_rx;
+ xfer.len = pkt_len;
+ spi_message_add_tail(&xfer, &msg);
+ err = apple_z2_spi_sync(z2, &msg);
+
+ if (!err)
+ apple_z2_parse_touches(z2, pkt_rx + 5, pkt_len - 5);
+
+ kfree(pkt_rx);
+ return err;
+}
+
+static irqreturn_t apple_z2_irq(int irq, void *data)
+{
+ struct spi_device *spi = data;
+ struct apple_z2 *z2 = spi_get_drvdata(spi);
+
+ if (!z2->booted)
+ complete(&z2->boot_irq);
+ else
+ apple_z2_read_packet(z2);
+
+ return IRQ_HANDLED;
+}
+
+
+// Return value must be freed with kfree
+static char *apple_z2_build_cal_blob(struct apple_z2 *z2, u32 address, u32 *size)
+{
+ u16 len_words = (z2->cal_size + 3) / 4;
+ u32 checksum = 0;
+ u16 checksum_hdr = 0;
+ char *data;
+ int i;
+ struct z2_hbpp_blob_hdr *hdr;
+
+ *size = z2->cal_size + sizeof(struct z2_hbpp_blob_hdr) + 4;
+
+ data = kzalloc(*size, GFP_KERNEL);
+ hdr = (struct z2_hbpp_blob_hdr *)data;
+ hdr->cmd = Z2_HBPP_CMD_BLOB;
+ hdr->len = len_words;
+ hdr->addr = address;
+
+ for (i = 2; i < 8; i++)
+ checksum_hdr += data[i];
+
+ hdr->checksum = checksum_hdr;
+ memcpy(data + 10, z2->cal_blob, z2->cal_size);
+
+ for (i = 0; i < z2->cal_size; i++)
+ checksum += z2->cal_blob[i];
+
+ *(u32 *)(data + z2->cal_size + 10) = checksum;
+
+ return data;
+}
+
+static int apple_z2_send_firmware_blob(struct apple_z2 *z2, const char *data, u32 size, u8 bpw)
+{
+ struct spi_message msg;
+ struct spi_transfer blob_xfer, ack_xfer;
+ char int_ack[] = {0x1a, 0xa1};
+ char ack_rsp[] = {0, 0};
+ int err;
+
+ spi_message_init(&msg);
+ memset(&blob_xfer, 0, sizeof(blob_xfer));
+ memset(&ack_xfer, 0, sizeof(ack_xfer));
+ blob_xfer.tx_buf = data;
+ blob_xfer.len = size;
+ blob_xfer.bits_per_word = bpw;
+ spi_message_add_tail(&blob_xfer, &msg);
+ ack_xfer.tx_buf = int_ack;
+ ack_xfer.rx_buf = ack_rsp;
+ ack_xfer.len = 2;
+ spi_message_add_tail(&ack_xfer, &msg);
+ reinit_completion(&z2->boot_irq);
+ err = apple_z2_spi_sync(z2, &msg);
+ if (err)
+ return err;
+ wait_for_completion_timeout(&z2->boot_irq, msecs_to_jiffies(20));
+ return 0;
+}
+
+static int apple_z2_upload_firmware(struct apple_z2 *z2)
+{
+ const struct firmware *fw;
+ struct z2_fw_hdr *fw_hdr;
+ size_t fw_idx = sizeof(struct z2_fw_hdr);
+ int err;
+ u32 load_cmd;
+ u32 size;
+ u32 address;
+ char *data;
+
+ err = request_firmware(&fw, z2->fw_name, &z2->spidev->dev);
+ if (err)
+ return dev_err_probe(&z2->spidev->dev, err, "unable to load firmware");
+
+ fw_hdr = (struct z2_fw_hdr *)fw->data;
+ if (fw_hdr->magic != Z2_FW_MAGIC || fw_hdr->version != 1)
+ return dev_err_probe(&z2->spidev->dev, -EINVAL, "invalid firmware header");
+
+ while (fw_idx < fw->size) {
+ if (fw->size - fw_idx < 8) {
+ err = dev_err_probe(&z2->spidev->dev, -EINVAL, "firmware malformed");
+ goto error;
+ }
+
+ load_cmd = *(u32 *)(fw->data + fw_idx);
+ fw_idx += 4;
+ if (load_cmd == LOAD_COMMAND_INIT_PAYLOAD || load_cmd == LOAD_COMMAND_SEND_BLOB) {
+ size = *(u32 *)(fw->data + fw_idx);
+ fw_idx += 4;
+ if (fw->size - fw_idx < size) {
+ err = dev_err_probe(&z2->spidev->dev,
+ -EINVAL, "firmware malformed");
+ goto error;
+ }
+ err = apple_z2_send_firmware_blob(z2, fw->data + fw_idx,
+ size, load_cmd == LOAD_COMMAND_SEND_BLOB ? 16 : 8);
+ if (err)
+ goto error;
+ fw_idx += size;
+ } else if (load_cmd == 2) {
+ address = *(u32 *)(fw->data + fw_idx);
+ fw_idx += 4;
+ data = apple_z2_build_cal_blob(z2, address, &size);
+ err = apple_z2_send_firmware_blob(z2, data, size, 16);
+ kfree(data);
+ if (err)
+ goto error;
+ } else {
+ err = dev_err_probe(&z2->spidev->dev, -EINVAL, "firmware malformed");
+ goto error;
+ }
+ if (fw_idx % 4 != 0)
+ fw_idx += 4 - (fw_idx % 4);
+ }
+
+
+ z2->booted = 1;
+ apple_z2_read_packet(z2);
+ error:
+ release_firmware(fw);
+ return err;
+}
+
+static int apple_z2_boot(struct apple_z2 *z2)
+{
+ int err;
+ enable_irq(z2->spidev->irq);
+ gpiod_direction_output(z2->reset_gpio, 1);
+ wait_for_completion_timeout(&z2->boot_irq, msecs_to_jiffies(20));
+ err = apple_z2_upload_firmware(z2);
+ if (err) { // Boot failed, let's put the device into reset just in case.
+ gpiod_direction_output(z2->reset_gpio, 0);
+ disable_irq(z2->spidev->irq);
+ }
+ return err;
+}
+
+static int apple_z2_probe(struct spi_device *spi)
+{
+ struct device *dev = &spi->dev;
+ struct apple_z2 *z2;
+ int err;
+ int x_size;
+ const char *device_name;
+
+ z2 = devm_kzalloc(dev, sizeof(*z2), GFP_KERNEL);
+ if (!z2)
+ return -ENOMEM;
+
+ z2->spidev = spi;
+ init_completion(&z2->boot_irq);
+ spi_set_drvdata(spi, z2);
+
+ z2->cs_gpio = devm_gpiod_get_index(dev, "cs", 0, 0);
+ if (IS_ERR(z2->cs_gpio))
+ return dev_err_probe(dev, PTR_ERR(z2->cs_gpio), "unable to get cs");
+
+ z2->reset_gpio = devm_gpiod_get_index(dev, "reset", 0, 0);
+ if (IS_ERR(z2->reset_gpio))
+ return dev_err_probe(dev, PTR_ERR(z2->reset_gpio), "unable to get reset");
+
+ err = devm_request_threaded_irq(dev, z2->spidev->irq, NULL,
+ apple_z2_irq, IRQF_ONESHOT | IRQF_NO_AUTOEN,
+ "apple-z2-irq", spi);
+ if (err < 0)
+ return dev_err_probe(dev, z2->spidev->irq, "unable to request irq");
+
+ err = device_property_read_u32(dev, "touchscreen-size-x", &x_size);
+ if (err)
+ return dev_err_probe(dev, err, "unable to get touchscreen size");
+
+ err = device_property_read_u32(dev, "touchscreen-size-y", &z2->y_size);
+ if (err)
+ return dev_err_probe(dev, err, "unable to get touchscreen size");
+
+ err = device_property_read_string(dev, "apple,z2-device-name", &device_name);
+ if (err)
+ return dev_err_probe(dev, err, "unable to get device name");
+
+ err = device_property_read_string(dev, "firmware-name", &z2->fw_name);
+ if (err)
+ return dev_err_probe(dev, err, "unable to get firmware name");
+
+ z2->cal_blob = of_get_property(dev->of_node, "apple,z2-cal-blob", &z2->cal_size);
+ if (!z2->cal_blob)
+ return dev_err_probe(dev, -EINVAL, "unable to get calibration");
+
+ z2->input_dev = devm_input_allocate_device(dev);
+ if (!z2->input_dev)
+ return -ENOMEM;
+ z2->input_dev->name = device_name;
+ z2->input_dev->phys = "apple_z2";
+ z2->input_dev->dev.parent = dev;
+ z2->input_dev->id.bustype = BUS_SPI;
+ input_set_abs_params(z2->input_dev, ABS_MT_POSITION_X, 0, x_size, 0, 0);
+ input_abs_set_res(z2->input_dev, ABS_MT_POSITION_X, 1);
+ input_set_abs_params(z2->input_dev, ABS_MT_POSITION_Y, 0, z2->y_size, 0, 0);
+ input_abs_set_res(z2->input_dev, ABS_MT_POSITION_Y, 1);
+ input_set_abs_params(z2->input_dev, ABS_MT_WIDTH_MAJOR, 0, 65535, 0, 0);
+ input_set_abs_params(z2->input_dev, ABS_MT_WIDTH_MINOR, 0, 65535, 0, 0);
+ input_set_abs_params(z2->input_dev, ABS_MT_TOUCH_MAJOR, 0, 65535, 0, 0);
+ input_set_abs_params(z2->input_dev, ABS_MT_TOUCH_MINOR, 0, 65535, 0, 0);
+ input_set_abs_params(z2->input_dev, ABS_MT_ORIENTATION, -32768, 32767, 0, 0);
+ input_mt_init_slots(z2->input_dev, 256, INPUT_MT_DIRECT);
+
+ err = input_register_device(z2->input_dev);
+ if (err < 0)
+ return dev_err_probe(dev, err, "unable to register input device");
+
+
+ // Reset the device on probe
+ gpiod_direction_output(z2->reset_gpio, 0);
+ usleep_range(5000, 10000);
+ return apple_z2_boot(z2);
+}
+
+static void apple_z2_remove(struct spi_device *spi)
+{
+ struct apple_z2 *z2 = spi_get_drvdata(spi);
+
+ disable_irq(z2->spidev->irq);
+ gpiod_direction_output(z2->reset_gpio, 0);
+}
+
+static void apple_z2_shutdown(struct spi_device *spi)
+{
+ struct apple_z2 *z2 = spi_get_drvdata(spi);
+
+ disable_irq(z2->spidev->irq);
+ gpiod_direction_output(z2->reset_gpio, 0);
+}
+
+static int apple_z2_suspend(struct device *dev)
+{
+ apple_z2_shutdown(to_spi_device(dev));
+ return 0;
+}
+
+static int apple_z2_resume(struct device *dev)
+{
+ struct apple_z2 *z2 = spi_get_drvdata(to_spi_device(dev));
+
+ return apple_z2_boot(z2);
+}
+
+static DEFINE_SIMPLE_DEV_PM_OPS(apple_z2_pm, apple_z2_suspend, apple_z2_resume);
+
+static const struct of_device_id apple_z2_of_match[] = {
+ { .compatible = "apple,z2-touchscreen" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, apple_z2_of_match);
+
+static struct spi_device_id apple_z2_of_id[] = {
+ { .name = "z2-touchscreen" },
+ {}
+};
+MODULE_DEVICE_TABLE(spi, apple_z2_of_id);
+
+static struct spi_driver apple_z2_driver = {
+ .driver = {
+ .name = "apple-z2",
+ .pm = pm_sleep_ptr(&apple_z2_pm),
+ .owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(apple_z2_of_match),
+ },
+
+ .id_table = apple_z2_of_id,
+ .probe = apple_z2_probe,
+ .remove = apple_z2_remove,
+ .shutdown = apple_z2_shutdown,
+};
+
+module_spi_driver(apple_z2_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_FIRMWARE("apple/mtfw-*.bin");
--
Git-137.1)
