[PATCH v2 09/12] remoteproc: stm32: Update M4 state in stm32_rproc_stop()

From: Mathieu Poirier
Date: Fri Apr 24 2020 - 16:25:34 EST


Update the M4 co-processor state in function stm32_rproc_stop() so
that it can be used in synchronisation scenarios.

Mainly based on the work published by Arnaud Pouliquen [1].

[1]. https://patchwork.kernel.org/project/linux-remoteproc/list/?series=239877

Signed-off-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
---
drivers/remoteproc/stm32_rproc.c | 13 +++++++++++++
1 file changed, 13 insertions(+)

diff --git a/drivers/remoteproc/stm32_rproc.c b/drivers/remoteproc/stm32_rproc.c
index 404f17a97095..86d23c35d805 100644
--- a/drivers/remoteproc/stm32_rproc.c
+++ b/drivers/remoteproc/stm32_rproc.c
@@ -493,6 +493,18 @@ static int stm32_rproc_stop(struct rproc *rproc)
}
}

+ /* update coprocessor state to OFF if available */
+ if (ddata->m4_state.map) {
+ err = regmap_update_bits(ddata->m4_state.map,
+ ddata->m4_state.reg,
+ ddata->m4_state.mask,
+ M4_STATE_OFF);
+ if (err) {
+ dev_err(&rproc->dev, "failed to set copro state\n");
+ return err;
+ }
+ }
+
return 0;
}

@@ -531,6 +543,7 @@ static struct rproc_ops st_rproc_ops = {

static __maybe_unused struct rproc_ops st_rproc_sync_ops = {
.start = stm32_rproc_sync_start,
+ .stop = stm32_rproc_stop,
};

static const struct of_device_id stm32_rproc_match[] = {
--
2.20.1