diff options
Diffstat (limited to 'drivers/media/platform/vivid/vivid-kthread-touch.c')
-rw-r--r-- | drivers/media/platform/vivid/vivid-kthread-touch.c | 181 |
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; +} |