lkml.org 
[lkml]   [2021]   [Nov]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] media: aspeed: use reset to replace clk off/on
Date
reset should be more proper than clk off/on to bring HW back to good
state.

Signed-off-by: Jammy Huang <jammy_huang@aspeedtech.com>
---
drivers/media/platform/aspeed-video.c | 22 +++++++++++++++++++---
1 file changed, 19 insertions(+), 3 deletions(-)

diff --git a/drivers/media/platform/aspeed-video.c b/drivers/media/platform/aspeed-video.c
index fea5e4d0927e..10d182139809 100644
--- a/drivers/media/platform/aspeed-video.c
+++ b/drivers/media/platform/aspeed-video.c
@@ -23,6 +23,7 @@
#include <linux/workqueue.h>
#include <linux/debugfs.h>
#include <linux/ktime.h>
+#include <linux/reset.h>
#include <media/v4l2-ctrls.h>
#include <media/v4l2-dev.h>
#include <media/v4l2-device.h>
@@ -220,6 +221,7 @@ struct aspeed_video {
void __iomem *base;
struct clk *eclk;
struct clk *vclk;
+ struct reset_control *reset;

struct device *dev;
struct v4l2_ctrl_handler ctrl_handler;
@@ -554,6 +556,13 @@ static void aspeed_video_on(struct aspeed_video *video)
set_bit(VIDEO_CLOCKS_ON, &video->flags);
}

+static void aspeed_video_reset(struct aspeed_video *v)
+{
+ reset_control_assert(v->reset);
+ udelay(100);
+ reset_control_deassert(v->reset);
+}
+
static void aspeed_video_bufs_done(struct aspeed_video *video,
enum vb2_buffer_state state)
{
@@ -574,7 +583,9 @@ static void aspeed_video_irq_res_change(struct aspeed_video *video, ulong delay)
set_bit(VIDEO_RES_CHANGE, &video->flags);
clear_bit(VIDEO_FRAME_INPRG, &video->flags);

- aspeed_video_off(video);
+ aspeed_video_write(video, VE_INTERRUPT_CTRL, 0);
+ aspeed_video_write(video, VE_INTERRUPT_STATUS, 0xffffffff);
+ aspeed_video_reset(video);
aspeed_video_bufs_done(video, VB2_BUF_STATE_ERROR);

schedule_delayed_work(&video->res_work, delay);
@@ -1507,8 +1518,7 @@ static void aspeed_video_stop_streaming(struct vb2_queue *q)
* Need to force stop any DMA and try and get HW into a good
* state for future calls to start streaming again.
*/
- aspeed_video_off(video);
- aspeed_video_on(video);
+ aspeed_video_reset(video);

aspeed_video_init_regs(video);

@@ -1715,6 +1725,12 @@ static int aspeed_video_init(struct aspeed_video *video)
return rc;
}

+ video->reset = devm_reset_control_get(dev, NULL);
+ if (IS_ERR(video->reset)) {
+ dev_err(dev, "Unable to get reset\n");
+ return PTR_ERR(video->reset);
+ }
+
video->eclk = devm_clk_get(dev, "eclk");
if (IS_ERR(video->eclk)) {
dev_err(dev, "Unable to get ECLK\n");
--
2.25.1
\
 
 \ /
  Last update: 2021-11-03 06:43    [W:0.062 / U:0.072 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site