return ret;
}
+/**
+ * struct scmi_iterator - Iterator descriptor
+ * @msg: A reference to the message TX buffer; filled by @prepare_message with
+ * a proper custom command payload for each multi-part command request.
+ * @resp: A reference to the response RX buffer; used by @update_state and
+ * @process_response to parse the multi-part replies.
+ * @t: A reference to the underlying xfer initialized and used transparently by
+ * the iterator internal routines.
+ * @ph: A reference to the associated protocol handle to be used.
+ * @ops: A reference to the custom provided iterator operations.
+ * @state: The current iterator state; used and updated in turn by the iterators
+ * internal routines and by the caller-provided @scmi_iterator_ops.
+ * @priv: A reference to optional private data as provided by the caller and
+ * passed back to the @@scmi_iterator_ops.
+ */
+struct scmi_iterator {
+ void *msg;
+ void *resp;
+ struct scmi_xfer *t;
+ const struct scmi_protocol_handle *ph;
+ struct scmi_iterator_ops *ops;
+ struct scmi_iterator_state state;
+ void *priv;
+};
+
+static void *scmi_iterator_init(const struct scmi_protocol_handle *ph,
+ struct scmi_iterator_ops *ops,
+ unsigned int max_resources, u8 msg_id,
+ size_t tx_size, void *priv)
+{
+ int ret;
+ struct scmi_iterator *i;
+
+ i = devm_kzalloc(ph->dev, sizeof(*i), GFP_KERNEL);
+ if (!i)
+ return ERR_PTR(-ENOMEM);
+
+ i->ph = ph;
+ i->ops = ops;
+ i->priv = priv;
+
+ ret = ph->xops->xfer_get_init(ph, msg_id, tx_size, 0, &i->t);
+ if (ret) {
+ devm_kfree(ph->dev, i);
+ return ERR_PTR(ret);
+ }
+
+ i->state.max_resources = max_resources;
+ i->msg = i->t->tx.buf;
+ i->resp = i->t->rx.buf;
+
+ return i;
+}
+
+static int scmi_iterator_run(void *iter)
+{
+ int ret = -EINVAL;
+ struct scmi_iterator *i = iter;
+ struct scmi_iterator_state *st = &i->state;
+ struct scmi_iterator_ops *iops = i->ops;
+ const struct scmi_protocol_handle *ph = i->ph;
+ const struct scmi_xfer_ops *xops = ph->xops;
+
+ if (!i)
+ return ret;
+
+ do {
+ iops->prepare_message(i->msg, st->desc_index, i->priv);
+ ret = xops->do_xfer(ph, i->t);
+ if (ret)
+ break;
+
+ ret = iops->update_state(st, i->resp, i->priv);
+ if (ret)
+ break;
+
+ if (st->num_returned > st->max_resources - st->desc_index) {
+ dev_err(ph->dev,
+ "No. of resources can't exceed %d\n",
+ st->max_resources);
+ ret = -EINVAL;
+ break;
+ }
+
+ for (st->loop_idx = 0; st->loop_idx < st->num_returned;
+ st->loop_idx++) {
+ ret = iops->process_response(ph, i->resp, st, i->priv);
+ if (ret)
+ goto out;
+ }
+
+ st->desc_index += st->num_returned;
+ xops->reset_rx_to_maxsz(ph, i->t);
+ /*
+ * check for both returned and remaining to avoid infinite
+ * loop due to buggy firmware
+ */
+ } while (st->num_returned && st->num_remaining);
+
+out:
+ /* Finalize and destroy iterator */
+ xops->xfer_put(ph, i->t);
+ devm_kfree(ph->dev, i);
+
+ return ret;
+}
+
static const struct scmi_proto_helpers_ops helpers_ops = {
.extended_name_get = scmi_common_extended_name_get,
+ .iter_response_init = scmi_iterator_init,
+ .iter_response_run = scmi_iterator_run,
};
/**
};
/**
+ * struct scmi_iterator_state - Iterator current state descriptor
+ * @desc_index: Starting index for the current mulit-part request.
+ * @num_returned: Number of returned items in the last multi-part reply.
+ * @num_remaining: Number of remaining items in the multi-part message.
+ * @max_resources: Maximum acceptable number of items, configured by the caller
+ * depending on the underlying resources that it is querying.
+ * @loop_idx: The iterator loop index in the current multi-part reply.
+ * @priv: Optional pointer to some additional state-related private data setup
+ * by the caller during the iterations.
+ */
+struct scmi_iterator_state {
+ unsigned int desc_index;
+ unsigned int num_returned;
+ unsigned int num_remaining;
+ unsigned int max_resources;
+ unsigned int loop_idx;
+ void *priv;
+};
+
+/**
+ * struct scmi_iterator_ops - Custom iterator operations
+ * @prepare_message: An operation to provide the custom logic to fill in the
+ * SCMI command request pointed by @message. @desc_index is
+ * a reference to the next index to use in the multi-part
+ * request.
+ * @update_state: An operation to provide the custom logic to update the
+ * iterator state from the actual message response.
+ * @process_response: An operation to provide the custom logic needed to process
+ * each chunk of the multi-part message.
+ */
+struct scmi_iterator_ops {
+ void (*prepare_message)(void *message, unsigned int desc_index,
+ const void *priv);
+ int (*update_state)(struct scmi_iterator_state *st,
+ const void *response, void *priv);
+ int (*process_response)(const struct scmi_protocol_handle *ph,
+ const void *response,
+ struct scmi_iterator_state *st, void *priv);
+};
+
+/**
* struct scmi_proto_helpers_ops - References to common protocol helpers
* @extended_name_get: A common helper function to retrieve extended naming
* for the specified resource using the specified command.
* Result is returned as a NULL terminated string in the
* pre-allocated area pointed to by @name with maximum
* capacity of @len bytes.
+ * @iter_response_init: A common helper to initialize a generic iterator to
+ * parse multi-message responses: when run the iterator
+ * will take care to send the initial command request as
+ * specified by @msg_id and @tx_size and then to parse the
+ * multi-part responses using the custom operations
+ * provided in @ops.
+ * @iter_response_run: A common helper to trigger the run of a previously
+ * initialized iterator.
*/
struct scmi_proto_helpers_ops {
int (*extended_name_get)(const struct scmi_protocol_handle *ph,
u8 cmd_id, u32 res_id, char *name, size_t len);
+ void *(*iter_response_init)(const struct scmi_protocol_handle *ph,
+ struct scmi_iterator_ops *ops,
+ unsigned int max_resources, u8 msg_id,
+ size_t tx_size, void *priv);
+ int (*iter_response_run)(void *iter);
};
/**