--- /dev/null
+/*
+ * Driver for memory based ft5406 touchscreen
+ *
+ * Copyright (C) 2015 Raspberry Pi
+ *
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/input.h>
+#include <linux/irq.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/bitops.h>
+#include <linux/input/mt.h>
+#include <linux/kthread.h>
+#include <linux/platform_device.h>
+#include <linux/stddef.h>
+#include <asm/io.h>
+#include <linux/dma-mapping.h>
+#include <soc/bcm2835/raspberrypi-firmware.h>
+
+#define MAXIMUM_SUPPORTED_POINTS 10
+struct ft5406_regs {
+ uint8_t device_mode;
+ uint8_t gesture_id;
+ uint8_t num_points;
+ struct ft5406_touch {
+ uint8_t xh;
+ uint8_t xl;
+ uint8_t yh;
+ uint8_t yl;
+ uint8_t res1;
+ uint8_t res2;
+ } point[MAXIMUM_SUPPORTED_POINTS];
+};
+
+#define SCREEN_WIDTH 800
+#define SCREEN_HEIGHT 480
+
+struct ft5406 {
+ struct platform_device * pdev;
+ struct input_dev * input_dev;
+ void __iomem * ts_base;
+ dma_addr_t bus_addr;
+ struct task_struct * thread;
+};
+
+/* Thread to poll for touchscreen events
+ *
+ * This thread polls the memory based register copy of the ft5406 registers
+ * using the number of points register to know whether the copy has been
+ * updated (we write 99 to the memory copy, the GPU will write between
+ * 0 - 10 points)
+ */
+static int ft5406_thread(void *arg)
+{
+ struct ft5406 *ts = (struct ft5406 *) arg;
+ struct ft5406_regs regs;
+ int known_ids = 0;
+
+ while(!kthread_should_stop())
+ {
+ // 60fps polling
+ msleep_interruptible(17);
+ memcpy_fromio(®s, ts->ts_base, sizeof(struct ft5406_regs));
+ iowrite8(99, ts->ts_base + offsetof(struct ft5406_regs, num_points));
+ // Do not output if theres no new information (num_points is 99)
+ // or we have no touch points and don't need to release any
+ if(!(regs.num_points == 99 || (regs.num_points == 0 && known_ids == 0)))
+ {
+ int i;
+ int modified_ids = 0, released_ids;
+ for(i = 0; i < regs.num_points; i++)
+ {
+ int x = (((int) regs.point[i].xh & 0xf) << 8) + regs.point[i].xl;
+ int y = (((int) regs.point[i].yh & 0xf) << 8) + regs.point[i].yl;
+ int touchid = (regs.point[i].yh >> 4) & 0xf;
+
+ modified_ids |= 1 << touchid;
+
+ if(!((1 << touchid) & known_ids))
+ dev_dbg(&ts->pdev->dev, "x = %d, y = %d, touchid = %d\n", x, y, touchid);
+
+ input_mt_slot(ts->input_dev, touchid);
+ input_mt_report_slot_state(ts->input_dev, MT_TOOL_FINGER, 1);
+
+ input_report_abs(ts->input_dev, ABS_MT_POSITION_X, x);
+ input_report_abs(ts->input_dev, ABS_MT_POSITION_Y, y);
+
+ }
+
+ released_ids = known_ids & ~modified_ids;
+ for(i = 0; released_ids && i < MAXIMUM_SUPPORTED_POINTS; i++)
+ {
+ if(released_ids & (1<<i))
+ {
+ dev_dbg(&ts->pdev->dev, "Released %d, known = %x modified = %x\n", i, known_ids, modified_ids);
+ input_mt_slot(ts->input_dev, i);
+ input_mt_report_slot_state(ts->input_dev, MT_TOOL_FINGER, 0);
+ modified_ids &= ~(1 << i);
+ }
+ }
+ known_ids = modified_ids;
+
+ input_mt_report_pointer_emulation(ts->input_dev, true);
+ input_sync(ts->input_dev);
+ }
+
+ }
+
+ return 0;
+}
+
+static int ft5406_probe(struct platform_device *pdev)
+{
+ int err = 0;
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ struct ft5406 * ts;
+ struct device_node *fw_node;
+ struct rpi_firmware *fw;
+ u32 touchbuf;
+
+ dev_info(dev, "Probing device\n");
+
+ fw_node = of_parse_phandle(np, "firmware", 0);
+ if (!fw_node) {
+ dev_err(dev, "Missing firmware node\n");
+ return -ENOENT;
+ }
+
+ fw = rpi_firmware_get(fw_node);
+ if (!fw)
+ return -EPROBE_DEFER;
+
+ ts = devm_kzalloc(dev, sizeof(struct ft5406), GFP_KERNEL);
+ if (!ts) {
+ dev_err(dev, "Failed to allocate memory\n");
+ return -ENOMEM;
+ }
+
+ ts->input_dev = input_allocate_device();
+ if (!ts->input_dev) {
+ dev_err(dev, "Failed to allocate input device\n");
+ return -ENOMEM;
+ }
+
+ ts->ts_base = dma_zalloc_coherent(dev, PAGE_SIZE, &ts->bus_addr, GFP_KERNEL);
+ if (!ts->ts_base) {
+ pr_err("[%s]: failed to dma_alloc_coherent(%ld)\n",
+ __func__, PAGE_SIZE);
+ err = -ENOMEM;
+ goto out;
+ }
+
+ touchbuf = (u32)ts->bus_addr;
+ err = rpi_firmware_property(fw, RPI_FIRMWARE_FRAMEBUFFER_SET_TOUCHBUF,
+ &touchbuf, sizeof(touchbuf));
+
+ if (err || touchbuf != 0) {
+ dev_warn(dev, "Failed to set touchbuf, trying to get err:%x\n", err);
+ dma_free_coherent(dev, PAGE_SIZE, ts->ts_base, ts->bus_addr);
+ ts->ts_base = 0;
+ ts->bus_addr = 0;
+ }
+
+ if (!ts->ts_base) {
+ dev_warn(dev, "set failed, trying get (err:%d touchbuf:%x virt:%p bus:%x)\n", err, touchbuf, ts->ts_base, ts->bus_addr);
+
+ err = rpi_firmware_property(fw, RPI_FIRMWARE_FRAMEBUFFER_GET_TOUCHBUF,
+ &touchbuf, sizeof(touchbuf));
+ if (err) {
+ dev_err(dev, "Failed to get touch buffer\n");
+ goto out;
+ }
+
+ if (!touchbuf) {
+ dev_err(dev, "Touchscreen not detected\n");
+ err = -ENODEV;
+ goto out;
+ }
+
+ dev_dbg(dev, "Got TS buffer 0x%x\n", touchbuf);
+
+ // mmap the physical memory
+ touchbuf &= ~0xc0000000;
+ ts->ts_base = ioremap(touchbuf, sizeof(struct ft5406_regs));
+ if (ts->ts_base == NULL)
+ {
+ dev_err(dev, "Failed to map physical address\n");
+ err = -ENOMEM;
+ goto out;
+ }
+ }
+ platform_set_drvdata(pdev, ts);
+ ts->pdev = pdev;
+
+ ts->input_dev->name = "FT5406 memory based driver";
+
+ __set_bit(EV_KEY, ts->input_dev->evbit);
+ __set_bit(EV_SYN, ts->input_dev->evbit);
+ __set_bit(EV_ABS, ts->input_dev->evbit);
+
+ input_set_abs_params(ts->input_dev, ABS_MT_POSITION_X, 0,
+ SCREEN_WIDTH, 0, 0);
+ input_set_abs_params(ts->input_dev, ABS_MT_POSITION_Y, 0,
+ SCREEN_HEIGHT, 0, 0);
+
+ input_mt_init_slots(ts->input_dev, MAXIMUM_SUPPORTED_POINTS, INPUT_MT_DIRECT);
+
+ input_set_drvdata(ts->input_dev, ts);
+
+ err = input_register_device(ts->input_dev);
+ if (err) {
+ dev_err(dev, "could not register input device, %d\n",
+ err);
+ goto out;
+ }
+
+ // create thread to poll the touch events
+ ts->thread = kthread_run(ft5406_thread, ts, "ft5406");
+ if(ts->thread == NULL)
+ {
+ dev_err(dev, "Failed to create kernel thread");
+ err = -ENOMEM;
+ goto out;
+ }
+
+ return 0;
+
+out:
+ if (ts->bus_addr) {
+ dma_free_coherent(dev, PAGE_SIZE, ts->ts_base, ts->bus_addr);
+ ts->bus_addr = 0;
+ ts->ts_base = NULL;
+ } else if (ts->ts_base) {
+ iounmap(ts->ts_base);
+ ts->ts_base = NULL;
+ }
+ if (ts->input_dev) {
+ input_unregister_device(ts->input_dev);
+ ts->input_dev = NULL;
+ }
+ return err;
+}
+
+static int ft5406_remove(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct ft5406 *ts = (struct ft5406 *) platform_get_drvdata(pdev);
+
+ dev_info(dev, "Removing rpi-ft5406\n");
+
+ kthread_stop(ts->thread);
+
+ if (ts->bus_addr)
+ dma_free_coherent(dev, PAGE_SIZE, ts->ts_base, ts->bus_addr);
+ else if (ts->ts_base)
+ iounmap(ts->ts_base);
+ if (ts->input_dev)
+ input_unregister_device(ts->input_dev);
+
+ return 0;
+}
+
+static const struct of_device_id ft5406_match[] = {
+ { .compatible = "rpi,rpi-ft5406", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, ft5406_match);
+
+static struct platform_driver ft5406_driver = {
+ .driver = {
+ .name = "rpi-ft5406",
+ .owner = THIS_MODULE,
+ .of_match_table = ft5406_match,
+ },
+ .probe = ft5406_probe,
+ .remove = ft5406_remove,
+};
+
+module_platform_driver(ft5406_driver);
+
+MODULE_AUTHOR("Gordon Hollingworth");
+MODULE_DESCRIPTION("Touchscreen driver for memory based FT5406");
+MODULE_LICENSE("GPL");
projects / mirror_ubuntu-zesty-kernel.git / commitdiff