media: vivid: Add touch support

Support to emulate touch devices in vivid driver.
It generates touch patterns simulating single tap, double tap, triple
tap, move from left to right, zoom in, zoom out, palm press simulating
large area being pressed on screen, and simulating 16 different
simultaneous touch points.The values generated are based on
behavior of the rmi_f54 driver.

Signed-off-by: Vandana BN <bnvandana@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

1 files changed, 181 insertions, 0 deletions

diff --git a/drivers/media/platform/vivid/vivid-kthread-touch.c b/drivers/media/platform/vivid/vivid-kthread-touch.c
new file mode 100644
index 000000000000..674507b5ccb5
--- /dev/null
+++ b/drivers/media/platform/vivid/vivid-kthread-touch.c
@@ -0,0 +1,181 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * vivid-kthread-touch.c - touch capture thread support functions.
+ *
+ */
+
+#include <linux/freezer.h>
+#include "vivid-core.h"
+#include "vivid-kthread-touch.h"
+#include "vivid-touch-cap.h"
+
+static noinline_for_stack void vivid_thread_tch_cap_tick(struct vivid_dev *dev,
+							 int dropped_bufs)
+{
+	struct vivid_buffer *tch_cap_buf = NULL;
+
+	spin_lock(&dev->slock);
+	if (!list_empty(&dev->touch_cap_active)) {
+		tch_cap_buf = list_entry(dev->touch_cap_active.next,
+					 struct vivid_buffer, list);
+		list_del(&tch_cap_buf->list);
+	}
+
+	spin_unlock(&dev->slock);
+
+	if (tch_cap_buf) {
+		v4l2_ctrl_request_setup(tch_cap_buf->vb.vb2_buf.req_obj.req,
+					&dev->ctrl_hdl_touch_cap);
+
+		vivid_fillbuff_tch(dev, tch_cap_buf);
+		v4l2_ctrl_request_complete(tch_cap_buf->vb.vb2_buf.req_obj.req,
+					   &dev->ctrl_hdl_touch_cap);
+		vb2_buffer_done(&tch_cap_buf->vb.vb2_buf, dev->dqbuf_error ?
+				VB2_BUF_STATE_ERROR : VB2_BUF_STATE_DONE);
+		dprintk(dev, 2, "touch_cap buffer %d done\n",
+			tch_cap_buf->vb.vb2_buf.index);
+
+		tch_cap_buf->vb.vb2_buf.timestamp = ktime_get_ns() + dev->time_wrap_offset;
+	}
+	dev->dqbuf_error = false;
+}
+
+static int vivid_thread_touch_cap(void *data)
+{
+	struct vivid_dev *dev = data;
+	u64 numerators_since_start;
+	u64 buffers_since_start;
+	u64 next_jiffies_since_start;
+	unsigned long jiffies_since_start;
+	unsigned long cur_jiffies;
+	unsigned int wait_jiffies;
+	unsigned int numerator;
+	unsigned int denominator;
+	int dropped_bufs;
+
+	dprintk(dev, 1, "Touch Capture Thread Start\n");
+
+	set_freezable();
+
+	/* Resets frame counters */
+	dev->touch_cap_seq_offset = 0;
+	dev->touch_cap_seq_count = 0;
+	dev->touch_cap_seq_resync = false;
+	dev->jiffies_touch_cap = jiffies;
+
+	for (;;) {
+		try_to_freeze();
+		if (kthread_should_stop())
+			break;
+
+		if (!mutex_trylock(&dev->mutex)) {
+			schedule_timeout_uninterruptible(1);
+			continue;
+		}
+		cur_jiffies = jiffies;
+		if (dev->touch_cap_seq_resync) {
+			dev->jiffies_touch_cap = cur_jiffies;
+			dev->touch_cap_seq_offset = dev->touch_cap_seq_count + 1;
+			dev->touch_cap_seq_count = 0;
+			dev->cap_seq_resync = false;
+		}
+		denominator = dev->timeperframe_tch_cap.denominator;
+		numerator = dev->timeperframe_tch_cap.numerator;
+
+		/* Calculate the number of jiffies since we started streaming */
+		jiffies_since_start = cur_jiffies - dev->jiffies_touch_cap;
+		/* Get the number of buffers streamed since the start */
+		buffers_since_start = (u64)jiffies_since_start * denominator +
+				      (HZ * numerator) / 2;
+		do_div(buffers_since_start, HZ * numerator);
+
+		/*
+		 * After more than 0xf0000000 (rounded down to a multiple of
+		 * 'jiffies-per-day' to ease jiffies_to_msecs calculation)
+		 * jiffies have passed since we started streaming reset the
+		 * counters and keep track of the sequence offset.
+		 */
+		if (jiffies_since_start > JIFFIES_RESYNC) {
+			dev->jiffies_touch_cap = cur_jiffies;
+			dev->cap_seq_offset = buffers_since_start;
+			buffers_since_start = 0;
+		}
+		dropped_bufs = buffers_since_start + dev->touch_cap_seq_offset - dev->touch_cap_seq_count;
+		dev->touch_cap_seq_count = buffers_since_start + dev->touch_cap_seq_offset;
+
+		vivid_thread_tch_cap_tick(dev, dropped_bufs);
+
+		/*
+		 * Calculate the number of 'numerators' streamed
+		 * since we started, including the current buffer.
+		 */
+		numerators_since_start = ++buffers_since_start * numerator;
+
+		/* And the number of jiffies since we started */
+		jiffies_since_start = jiffies - dev->jiffies_touch_cap;
+
+		mutex_unlock(&dev->mutex);
+
+		/*
+		 * Calculate when that next buffer is supposed to start
+		 * in jiffies since we started streaming.
+		 */
+		next_jiffies_since_start = numerators_since_start * HZ +
+					   denominator / 2;
+		do_div(next_jiffies_since_start, denominator);
+		/* If it is in the past, then just schedule asap */
+		if (next_jiffies_since_start < jiffies_since_start)
+			next_jiffies_since_start = jiffies_since_start;
+
+		wait_jiffies = next_jiffies_since_start - jiffies_since_start;
+		schedule_timeout_interruptible(wait_jiffies ? wait_jiffies : 1);
+	}
+	dprintk(dev, 1, "Touch Capture Thread End\n");
+	return 0;
+}
+
+int vivid_start_generating_touch_cap(struct vivid_dev *dev)
+{
+	if (dev->kthread_touch_cap) {
+		dev->touch_cap_streaming = true;
+		return 0;
+	}
+
+	dev->kthread_touch_cap = kthread_run(vivid_thread_touch_cap, dev,
+					     "%s-tch-cap", dev->v4l2_dev.name);
+
+	if (IS_ERR(dev->kthread_touch_cap)) {
+		int err = PTR_ERR(dev->kthread_touch_cap);
+
+		dev->kthread_touch_cap = NULL;
+		v4l2_err(&dev->v4l2_dev, "kernel_thread() failed\n");
+		return err;
+	}
+	dev->touch_cap_streaming = true;
+	dprintk(dev, 1, "returning from %s\n", __func__);
+	return 0;
+}
+
+void vivid_stop_generating_touch_cap(struct vivid_dev *dev)
+{
+	if (!dev->kthread_touch_cap)
+		return;
+
+	dev->touch_cap_streaming = false;
+
+	while (!list_empty(&dev->touch_cap_active)) {
+		struct vivid_buffer *buf;
+
+		buf = list_entry(dev->touch_cap_active.next,
+				 struct vivid_buffer, list);
+		list_del(&buf->list);
+		v4l2_ctrl_request_complete(buf->vb.vb2_buf.req_obj.req,
+					   &dev->ctrl_hdl_touch_cap);
+		vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
+		dprintk(dev, 2, "touch_cap buffer %d done\n",
+			buf->vb.vb2_buf.index);
+	}
+
+	kthread_stop(dev->kthread_touch_cap);
+	dev->kthread_touch_cap = NULL;
+}