1 // SPDX-License-Identifier: GPL-2.0-only
7  * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com/
24  * of_dma_find_controller - Get a DMA controller in DT DMA helpers list
37 		if (ofdma->of_node == dma_spec->np)  in of_dma_find_controller()
41 		 dma_spec->np);  in of_dma_find_controller()
47  * of_dma_router_xlate - translation function for router devices
58 	struct dma_chan		*chan;  in of_dma_router_xlate()  local
65 	route_data = ofdma->of_dma_route_allocate(&dma_spec_target, ofdma);  in of_dma_router_xlate()
71 		ofdma->dma_router->route_free(ofdma->dma_router->dev,  in of_dma_router_xlate()
73 		chan = ERR_PTR(-EPROBE_DEFER);  in of_dma_router_xlate()
77 	chan = ofdma_target->of_dma_xlate(&dma_spec_target, ofdma_target);  in of_dma_router_xlate()
78 	if (IS_ERR_OR_NULL(chan)) {  in of_dma_router_xlate()
79 		ofdma->dma_router->route_free(ofdma->dma_router->dev,  in of_dma_router_xlate()
84 		chan->router = ofdma->dma_router;  in of_dma_router_xlate()
85 		chan->route_data = route_data;  in of_dma_router_xlate()
87 		if (chan->device->device_router_config)  in of_dma_router_xlate()
88 			ret = chan->device->device_router_config(chan);  in of_dma_router_xlate()
91 			dma_release_channel(chan);  in of_dma_router_xlate()
92 			chan = ERR_PTR(ret);  in of_dma_router_xlate()
98 	 * Need to put the node back since the ofdma->of_dma_route_allocate  in of_dma_router_xlate()
102 	return chan;  in of_dma_router_xlate()
106  * of_dma_controller_register - Register a DMA controller to DT DMA helpers
127 		return -EINVAL;  in of_dma_controller_register()
132 		return -ENOMEM;  in of_dma_controller_register()
134 	ofdma->of_node = np;  in of_dma_controller_register()
135 	ofdma->of_dma_xlate = of_dma_xlate;  in of_dma_controller_register()
136 	ofdma->of_dma_data = data;  in of_dma_controller_register()
140 	list_add_tail(&ofdma->of_dma_controllers, &of_dma_list);  in of_dma_controller_register()
148  * of_dma_controller_free - Remove a DMA controller from DT DMA helpers list
160 		if (ofdma->of_node == np) {  in of_dma_controller_free()
161 			list_del(&ofdma->of_dma_controllers);  in of_dma_controller_free()
171  * of_dma_router_register - Register a DMA router to DT DMA helpers as a
194 		return -EINVAL;  in of_dma_router_register()
199 		return -ENOMEM;  in of_dma_router_register()
201 	ofdma->of_node = np;  in of_dma_router_register()
202 	ofdma->of_dma_xlate = of_dma_router_xlate;  in of_dma_router_register()
203 	ofdma->of_dma_route_allocate = of_dma_route_allocate;  in of_dma_router_register()
204 	ofdma->dma_router = dma_router;  in of_dma_router_register()
208 	list_add_tail(&ofdma->of_dma_controllers, &of_dma_list);  in of_dma_router_register()
216  * of_dma_match_channel - Check if a DMA specifier matches name
218  * @name:	channel name to be matched
223  * specifiers, matches the name provided. Returns 0 if the name matches and
224  * a valid pointer to the DMA specifier is found. Otherwise returns -ENODEV.
226 static int of_dma_match_channel(struct device_node *np, const char *name,  in of_dma_match_channel()  argument
231 	if (of_property_read_string_index(np, "dma-names", index, &s))  in of_dma_match_channel()
232 		return -ENODEV;  in of_dma_match_channel()
234 	if (strcmp(name, s))  in of_dma_match_channel()
235 		return -ENODEV;  in of_dma_match_channel()
237 	if (of_parse_phandle_with_args(np, "dmas", "#dma-cells", index,  in of_dma_match_channel()
239 		return -ENODEV;  in of_dma_match_channel()
245  * of_dma_request_slave_channel - Get the DMA slave channel
247  * @name:	name of desired channel
252 					      const char *name)  in of_dma_request_slave_channel()  argument
256 	struct dma_chan		*chan;  in of_dma_request_slave_channel()  local
258 	int			ret_no_channel = -ENODEV;  in of_dma_request_slave_channel()
261 	if (!np || !name) {  in of_dma_request_slave_channel()
263 		return ERR_PTR(-ENODEV);  in of_dma_request_slave_channel()
268 		return ERR_PTR(-ENODEV);  in of_dma_request_slave_channel()
270 	count = of_property_count_strings(np, "dma-names");  in of_dma_request_slave_channel()
272 		pr_err("%s: dma-names property of node '%pOF' missing or empty\n",  in of_dma_request_slave_channel()
274 		return ERR_PTR(-ENODEV);  in of_dma_request_slave_channel()
279 	 * entries with the same name  in of_dma_request_slave_channel()
283 		if (of_dma_match_channel(np, name,  in of_dma_request_slave_channel()
292 			chan = ofdma->of_dma_xlate(&dma_spec, ofdma);  in of_dma_request_slave_channel()
294 			ret_no_channel = -EPROBE_DEFER;  in of_dma_request_slave_channel()
295 			chan = NULL;  in of_dma_request_slave_channel()
302 		if (chan)  in of_dma_request_slave_channel()
303 			return chan;  in of_dma_request_slave_channel()
311  * of_dma_simple_xlate - Simple DMA engine translation function
315  * A simple translation function for devices that use a 32-bit value for the
317  * Note that this translation function requires that #dma-cells is equal to 1
318  * and the argument of the dma specifier is the 32-bit filter_param. Returns
324 	int count = dma_spec->args_count;  in of_dma_simple_xlate()
325 	struct of_dma_filter_info *info = ofdma->of_dma_data;  in of_dma_simple_xlate()
327 	if (!info || !info->filter_fn)  in of_dma_simple_xlate()
333 	return __dma_request_channel(&info->dma_cap, info->filter_fn,  in of_dma_simple_xlate()
334 				     &dma_spec->args[0], dma_spec->np);  in of_dma_simple_xlate()
339  * of_dma_xlate_by_chan_id - Translate dt property to DMA channel by channel id
345  * the #dma-cells propety of the DMA controller dt node needs to be set to 1.
354 	struct dma_device *dev = ofdma->of_dma_data;  in of_dma_xlate_by_chan_id()
355 	struct dma_chan *chan, *candidate = NULL;  in of_dma_xlate_by_chan_id()  local
357 	if (!dev || dma_spec->args_count != 1)  in of_dma_xlate_by_chan_id()
360 	list_for_each_entry(chan, &dev->channels, device_node)  in of_dma_xlate_by_chan_id()
361 		if (chan->chan_id == dma_spec->args[0]) {  in of_dma_xlate_by_chan_id()
362 			candidate = chan;  in of_dma_xlate_by_chan_id()