remoteproc: stm32: Update M4 state in stm32_rproc_stop()

Update the co-processor state in function stm32_rproc_stop() so that
it can be used in scenarios where the remoteproc core is attaching
to the M4.

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

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

Acked-by: Arnaud Pouliquen <arnaud.pouliquen@st.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Arnaud Pouliquen <arnaud.pouliquen@st.com>
Link: https://lore.kernel.org/r/20200714200445.1427257-12-mathieu.poirier@linaro.org
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>

diff --git a/drivers/remoteproc/stm32_rproc.c b/drivers/remoteproc/stm32_rproc.c
index 7145cd49616e81374919ea85e9610eac2c98f4be..f4da42fc0eeb1423dabbde2802f616a6006a8426 100644 (file)
--- a/drivers/remoteproc/stm32_rproc.c
+++ b/drivers/remoteproc/stm32_rproc.c
@@ -504,6 +504,18 @@ 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;
 }