The Ths_settle timing parameter depends solely on the lane data rate of
the source. Calculate it at runtime instead of requiring it to be
specified in the device tree.
Signed-off-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
---
Changes since v1:
- Unlock mutex in mipi_csis_link_setup() error path
- Use v4l2_get_link_freq()
---
drivers/staging/media/imx/imx7-mipi-csis.c | 43 ++++++++++++++++++++--
1 file changed, 39 insertions(+), 4 deletions(-)
diff --git a/drivers/staging/media/imx/imx7-mipi-csis.c b/drivers/staging/media/imx/imx7-mipi-csis.c
index 333ab3966b5b..4a51d2440b64 100644
--- a/drivers/staging/media/imx/imx7-mipi-csis.c
+++ b/drivers/staging/media/imx/imx7-mipi-csis.c
@@ -24,6 +24,7 @@
#include <linux/reset.h>
#include <linux/spinlock.h>
+#include <media/v4l2-common.h>
#include <media/v4l2-device.h>
#include <media/v4l2-fwnode.h>
#include <media/v4l2-mc.h>
@@ -482,6 +483,39 @@ static void __mipi_csis_set_format(struct csi_state *state)
mipi_csis_write(state, MIPI_CSIS_ISPRESOL_CH0, val);
}
+static int mipi_csis_calculate_params(struct csi_state *state)
+{
+ s64 link_freq;
+ u32 lane_rate;
+
+ /* Calculate the line rate from the pixel rate. */
+ link_freq = v4l2_get_link_freq(state->src_sd->ctrl_handler,
+ state->csis_fmt->width,
+ state->bus.num_data_lanes * 2);
+ if (link_freq < 0) {
+ dev_err(state->dev, "Unable to obtain link frequency: %d\n",
+ (int)link_freq);
+ return link_freq;
+ }
+
+ lane_rate = link_freq * 2;
+
+ if (lane_rate < 80000000 || lane_rate > 1500000000) {
+ dev_dbg(state->dev, "Out-of-bound lane rate %u\n", lane_rate);
+ return -EINVAL;
+ }
+
+ /*
+ * The HSSETTLE counter value is document in a table, but can also
+ * easily be calculated.
+ */
+ state->hs_settle = (lane_rate - 5000000) / 45000000;
+ dev_dbg(state->dev, "lane rate %u, Ths_settle %u\n",
+ lane_rate, state->hs_settle);
+
+ return 0;
+}
+
static void mipi_csis_set_params(struct csi_state *state)
{
int lanes = state->bus.num_data_lanes;
@@ -608,9 +642,13 @@ static void mipi_csis_log_counters(struct csi_state *state, bool non_errors)
static int mipi_csis_s_stream(struct v4l2_subdev *mipi_sd, int enable)
{
struct csi_state *state = mipi_sd_to_csis_state(mipi_sd);
- int ret = 0;
+ int ret;
if (enable) {
+ ret = mipi_csis_calculate_params(state);
+ if (ret < 0)
+ return ret;
+
mipi_csis_clear_counters(state);
ret = pm_runtime_get_sync(&state->pdev->dev);
if (ret < 0) {
@@ -943,9 +981,6 @@ static int mipi_csis_parse_dt(struct platform_device *pdev,
if (IS_ERR(state->mrst))
return PTR_ERR(state->mrst);
- /* Get MIPI CSI-2 bus configuration from the endpoint node. */
- of_property_read_u32(node, "fsl,csis-hs-settle", &state->hs_settle);
-
return 0;
}
--
Regards,
Laurent Pinchart
