[PATCH 07/16] media: cadence: csi2rx: Set the STOP bit when stopping a stream

Pratyush Yadav
2021-03-30T17:35:45Z

The stream stop procedure says that the STOP bit should be set when the
stream is to be stopped, and then the ready bit in stream status
register polled to make sure the STOP operation is finished.

Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
---
drivers/media/platform/cadence/cdns-csi2rx.c | 18 +++++++++++++++++-
1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/drivers/media/platform/cadence/cdns-csi2rx.c b/drivers/media/platform/cadence/cdns-csi2rx.c
index b03d2d2e6762..eca65b157f59 100644
--- a/drivers/media/platform/cadence/cdns-csi2rx.c
+++ b/drivers/media/platform/cadence/cdns-csi2rx.c
@@ -8,6 +8,7 @@
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/io.h>
+#include <linux/iopoll.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_graph.h>
@@ -40,8 +41,12 @@

#define CSI2RX_STREAM_CTRL_REG(n) (CSI2RX_STREAM_BASE(n) + 0x000)
#define CSI2RX_STREAM_CTRL_SOFT_RST BIT(4)
+#define CSI2RX_STREAM_CTRL_STOP BIT(1)
#define CSI2RX_STREAM_CTRL_START BIT(0)

+#define CSI2RX_STREAM_STATUS_REG(n) (CSI2RX_STREAM_BASE(n) + 0x004)
+#define CSI2RX_STREAM_STATUS_RDY BIT(31)
+
#define CSI2RX_STREAM_DATA_CFG_REG(n) (CSI2RX_STREAM_BASE(n) + 0x008)
#define CSI2RX_STREAM_DATA_CFG_EN_VC_SELECT BIT(31)
#define CSI2RX_STREAM_DATA_CFG_VC_SELECT(n) BIT((n) + 16)
@@ -325,12 +330,23 @@ static int csi2rx_start(struct csi2rx_priv *csi2rx)
static void csi2rx_stop(struct csi2rx_priv *csi2rx)
{
unsigned int i;
+ u32 val;
+ int ret;

clk_prepare_enable(csi2rx->p_clk);
clk_disable_unprepare(csi2rx->sys_clk);

for (i = 0; i < csi2rx->max_streams; i++) {
- writel(0, csi2rx->base + CSI2RX_STREAM_CTRL_REG(i));
+ writel(CSI2RX_STREAM_CTRL_STOP,
+ csi2rx->base + CSI2RX_STREAM_CTRL_REG(i));
+
+ ret = readl_relaxed_poll_timeout(csi2rx->base +
+ CSI2RX_STREAM_STATUS_REG(i),
+ val,
+ (val & CSI2RX_STREAM_STATUS_RDY),
+ 10, 10000);
+ if (ret)
+ dev_warn(csi2rx->dev, "Failed to stop stream%d\n", i);

clk_disable_unprepare(csi2rx->pixel_clk[i]);
}
--
2.30.0