Message ID | 20230531-rpm-rproc-v2-7-56a4a00c8260@gerhold.net |
---|---|
State | Accepted |
Commit | 181563be4373e70bfab82773e3fce571edea9629 |
Headers | show |
Series | Add dedicated device tree node for RPM processor/subsystem | expand |
On 8.06.2023 09:10, Stephan Gerhold wrote: > Rather than looking up a dummy item from SMEM, use the new > qcom_smem_is_available() function to make the code more clear > (and reduce the overhead slightly). > > Add the same check to qcom_smd_register_edge() as well to ensure that > it only succeeds if SMEM is already available - if a driver calls the > function and SMEM is not available yet then the initial state will be > read incorrectly and the RPMSG devices might never become available. > > Signed-off-by: Stephan Gerhold <stephan@gerhold.net> > --- Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org> Konrad > drivers/rpmsg/qcom_smd.c | 10 +++++----- > 1 file changed, 5 insertions(+), 5 deletions(-) > > diff --git a/drivers/rpmsg/qcom_smd.c b/drivers/rpmsg/qcom_smd.c > index 7b9c298aa491..43f601c84b4f 100644 > --- a/drivers/rpmsg/qcom_smd.c > +++ b/drivers/rpmsg/qcom_smd.c > @@ -1479,6 +1479,9 @@ struct qcom_smd_edge *qcom_smd_register_edge(struct device *parent, > struct qcom_smd_edge *edge; > int ret; > > + if (!qcom_smem_is_available()) > + return ERR_PTR(-EPROBE_DEFER); > + > edge = kzalloc(sizeof(*edge), GFP_KERNEL); > if (!edge) > return ERR_PTR(-ENOMEM); > @@ -1553,12 +1556,9 @@ EXPORT_SYMBOL(qcom_smd_unregister_edge); > static int qcom_smd_probe(struct platform_device *pdev) > { > struct device_node *node; > - void *p; > > - /* Wait for smem */ > - p = qcom_smem_get(QCOM_SMEM_HOST_ANY, smem_items[0].alloc_tbl_id, NULL); > - if (PTR_ERR(p) == -EPROBE_DEFER) > - return PTR_ERR(p); > + if (!qcom_smem_is_available()) > + return -EPROBE_DEFER; > > for_each_available_child_of_node(pdev->dev.of_node, node) > qcom_smd_register_edge(&pdev->dev, node); >
diff --git a/drivers/rpmsg/qcom_smd.c b/drivers/rpmsg/qcom_smd.c index 7b9c298aa491..43f601c84b4f 100644 --- a/drivers/rpmsg/qcom_smd.c +++ b/drivers/rpmsg/qcom_smd.c @@ -1479,6 +1479,9 @@ struct qcom_smd_edge *qcom_smd_register_edge(struct device *parent, struct qcom_smd_edge *edge; int ret; + if (!qcom_smem_is_available()) + return ERR_PTR(-EPROBE_DEFER); + edge = kzalloc(sizeof(*edge), GFP_KERNEL); if (!edge) return ERR_PTR(-ENOMEM); @@ -1553,12 +1556,9 @@ EXPORT_SYMBOL(qcom_smd_unregister_edge); static int qcom_smd_probe(struct platform_device *pdev) { struct device_node *node; - void *p; - /* Wait for smem */ - p = qcom_smem_get(QCOM_SMEM_HOST_ANY, smem_items[0].alloc_tbl_id, NULL); - if (PTR_ERR(p) == -EPROBE_DEFER) - return PTR_ERR(p); + if (!qcom_smem_is_available()) + return -EPROBE_DEFER; for_each_available_child_of_node(pdev->dev.of_node, node) qcom_smd_register_edge(&pdev->dev, node);
Rather than looking up a dummy item from SMEM, use the new qcom_smem_is_available() function to make the code more clear (and reduce the overhead slightly). Add the same check to qcom_smd_register_edge() as well to ensure that it only succeeds if SMEM is already available - if a driver calls the function and SMEM is not available yet then the initial state will be read incorrectly and the RPMSG devices might never become available. Signed-off-by: Stephan Gerhold <stephan@gerhold.net> --- drivers/rpmsg/qcom_smd.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-)