| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Jon Hunter | 571 | 52.58% | 3 | 17.65% |
| Peter Ujfalusi | 289 | 26.61% | 1 | 5.88% |
| Alexander Popov | 98 | 9.02% | 1 | 5.88% |
| Stephen Warren | 30 | 2.76% | 1 | 5.88% |
| Lars-Peter Clausen | 28 | 2.58% | 2 | 11.76% |
| Niklas Söderlund | 21 | 1.93% | 1 | 5.88% |
| Wolfram Sang | 20 | 1.84% | 1 | 5.88% |
| Andy Shevchenko | 10 | 0.92% | 1 | 5.88% |
| Baolin Wang | 6 | 0.55% | 1 | 5.88% |
| Kuninori Morimoto | 5 | 0.46% | 1 | 5.88% |
| Rob Herring | 2 | 0.18% | 1 | 5.88% |
| Lothar Waßmann | 2 | 0.18% | 1 | 5.88% |
| Markus Pargmann | 2 | 0.18% | 1 | 5.88% |
| Thomas Gleixner | 2 | 0.18% | 1 | 5.88% |
| Total | 1086 | 17 |
// SPDX-License-Identifier: GPL-2.0-only /* * Device tree helpers for DMA request / controller * * Based on of_gpio.c * * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com/ */ #include <linux/device.h> #include <linux/err.h> #include <linux/module.h> #include <linux/mutex.h> #include <linux/slab.h> #include <linux/of.h> #include <linux/of_dma.h> static LIST_HEAD(of_dma_list); static DEFINE_MUTEX(of_dma_lock); /** * of_dma_find_controller - Get a DMA controller in DT DMA helpers list * @dma_spec: pointer to DMA specifier as found in the device tree * * Finds a DMA controller with matching device node and number for dma cells * in a list of registered DMA controllers. If a match is found a valid pointer * to the DMA data stored is retuned. A NULL pointer is returned if no match is * found. */ static struct of_dma *of_dma_find_controller(struct of_phandle_args *dma_spec) { struct of_dma *ofdma; list_for_each_entry(ofdma, &of_dma_list, of_dma_controllers) if (ofdma->of_node == dma_spec->np) return ofdma; pr_debug("%s: can't find DMA controller %pOF\n", __func__, dma_spec->np); return NULL; } /** * of_dma_router_xlate - translation function for router devices * @dma_spec: pointer to DMA specifier as found in the device tree * @of_dma: pointer to DMA controller data (router information) * * The function creates new dma_spec to be passed to the router driver's * of_dma_route_allocate() function to prepare a dma_spec which will be used * to request channel from the real DMA controller. */ static struct dma_chan *of_dma_router_xlate(struct of_phandle_args *dma_spec, struct of_dma *ofdma) { struct dma_chan *chan; struct of_dma *ofdma_target; struct of_phandle_args dma_spec_target; void *route_data; /* translate the request for the real DMA controller */ memcpy(&dma_spec_target, dma_spec, sizeof(dma_spec_target)); route_data = ofdma->of_dma_route_allocate(&dma_spec_target, ofdma); if (IS_ERR(route_data)) return NULL; ofdma_target = of_dma_find_controller(&dma_spec_target); if (!ofdma_target) return NULL; chan = ofdma_target->of_dma_xlate(&dma_spec_target, ofdma_target); if (chan) { chan->router = ofdma->dma_router; chan->route_data = route_data; } else { ofdma->dma_router->route_free(ofdma->dma_router->dev, route_data); } /* * Need to put the node back since the ofdma->of_dma_route_allocate * has taken it for generating the new, translated dma_spec */ of_node_put(dma_spec_target.np); return chan; } /** * of_dma_controller_register - Register a DMA controller to DT DMA helpers * @np: device node of DMA controller * @of_dma_xlate: translation function which converts a phandle * arguments list into a dma_chan structure * @data pointer to controller specific data to be used by * translation function * * Returns 0 on success or appropriate errno value on error. * * Allocated memory should be freed with appropriate of_dma_controller_free() * call. */ int of_dma_controller_register(struct device_node *np, struct dma_chan *(*of_dma_xlate) (struct of_phandle_args *, struct of_dma *), void *data) { struct of_dma *ofdma; if (!np || !of_dma_xlate) { pr_err("%s: not enough information provided\n", __func__); return -EINVAL; } ofdma = kzalloc(sizeof(*ofdma), GFP_KERNEL); if (!ofdma) return -ENOMEM; ofdma->of_node = np; ofdma->of_dma_xlate = of_dma_xlate; ofdma->of_dma_data = data; /* Now queue of_dma controller structure in list */ mutex_lock(&of_dma_lock); list_add_tail(&ofdma->of_dma_controllers, &of_dma_list); mutex_unlock(&of_dma_lock); return 0; } EXPORT_SYMBOL_GPL(of_dma_controller_register); /** * of_dma_controller_free - Remove a DMA controller from DT DMA helpers list * @np: device node of DMA controller * * Memory allocated by of_dma_controller_register() is freed here. */ void of_dma_controller_free(struct device_node *np) { struct of_dma *ofdma; mutex_lock(&of_dma_lock); list_for_each_entry(ofdma, &of_dma_list, of_dma_controllers) if (ofdma->of_node == np) { list_del(&ofdma->of_dma_controllers); kfree(ofdma); break; } mutex_unlock(&of_dma_lock); } EXPORT_SYMBOL_GPL(of_dma_controller_free); /** * of_dma_router_register - Register a DMA router to DT DMA helpers as a * controller * @np: device node of DMA router * @of_dma_route_allocate: setup function for the router which need to * modify the dma_spec for the DMA controller to * use and to set up the requested route. * @dma_router: pointer to dma_router structure to be used when * the route need to be free up. * * Returns 0 on success or appropriate errno value on error. * * Allocated memory should be freed with appropriate of_dma_controller_free() * call. */ int of_dma_router_register(struct device_node *np, void *(*of_dma_route_allocate) (struct of_phandle_args *, struct of_dma *), struct dma_router *dma_router) { struct of_dma *ofdma; if (!np || !of_dma_route_allocate || !dma_router) { pr_err("%s: not enough information provided\n", __func__); return -EINVAL; } ofdma = kzalloc(sizeof(*ofdma), GFP_KERNEL); if (!ofdma) return -ENOMEM; ofdma->of_node = np; ofdma->of_dma_xlate = of_dma_router_xlate; ofdma->of_dma_route_allocate = of_dma_route_allocate; ofdma->dma_router = dma_router; /* Now queue of_dma controller structure in list */ mutex_lock(&of_dma_lock); list_add_tail(&ofdma->of_dma_controllers, &of_dma_list); mutex_unlock(&of_dma_lock); return 0; } EXPORT_SYMBOL_GPL(of_dma_router_register); /** * of_dma_match_channel - Check if a DMA specifier matches name * @np: device node to look for DMA channels * @name: channel name to be matched * @index: index of DMA specifier in list of DMA specifiers * @dma_spec: pointer to DMA specifier as found in the device tree * * Check if the DMA specifier pointed to by the index in a list of DMA * specifiers, matches the name provided. Returns 0 if the name matches and * a valid pointer to the DMA specifier is found. Otherwise returns -ENODEV. */ static int of_dma_match_channel(struct device_node *np, const char *name, int index, struct of_phandle_args *dma_spec) { const char *s; if (of_property_read_string_index(np, "dma-names", index, &s)) return -ENODEV; if (strcmp(name, s)) return -ENODEV; if (of_parse_phandle_with_args(np, "dmas", "#dma-cells", index, dma_spec)) return -ENODEV; return 0; } /** * of_dma_request_slave_channel - Get the DMA slave channel * @np: device node to get DMA request from * @name: name of desired channel * * Returns pointer to appropriate DMA channel on success or an error pointer. */ struct dma_chan *of_dma_request_slave_channel(struct device_node *np, const char *name) { struct of_phandle_args dma_spec; struct of_dma *ofdma; struct dma_chan *chan; int count, i, start; int ret_no_channel = -ENODEV; static atomic_t last_index; if (!np || !name) { pr_err("%s: not enough information provided\n", __func__); return ERR_PTR(-ENODEV); } /* Silently fail if there is not even the "dmas" property */ if (!of_find_property(np, "dmas", NULL)) return ERR_PTR(-ENODEV); count = of_property_count_strings(np, "dma-names"); if (count < 0) { pr_err("%s: dma-names property of node '%pOF' missing or empty\n", __func__, np); return ERR_PTR(-ENODEV); } /* * approximate an average distribution across multiple * entries with the same name */ start = atomic_inc_return(&last_index); for (i = 0; i < count; i++) { if (of_dma_match_channel(np, name, (i + start) % count, &dma_spec)) continue; mutex_lock(&of_dma_lock); ofdma = of_dma_find_controller(&dma_spec); if (ofdma) { chan = ofdma->of_dma_xlate(&dma_spec, ofdma); } else { ret_no_channel = -EPROBE_DEFER; chan = NULL; } mutex_unlock(&of_dma_lock); of_node_put(dma_spec.np); if (chan) return chan; } return ERR_PTR(ret_no_channel); } EXPORT_SYMBOL_GPL(of_dma_request_slave_channel); /** * of_dma_simple_xlate - Simple DMA engine translation function * @dma_spec: pointer to DMA specifier as found in the device tree * @of_dma: pointer to DMA controller data * * A simple translation function for devices that use a 32-bit value for the * filter_param when calling the DMA engine dma_request_channel() function. * Note that this translation function requires that #dma-cells is equal to 1 * and the argument of the dma specifier is the 32-bit filter_param. Returns * pointer to appropriate dma channel on success or NULL on error. */ struct dma_chan *of_dma_simple_xlate(struct of_phandle_args *dma_spec, struct of_dma *ofdma) { int count = dma_spec->args_count; struct of_dma_filter_info *info = ofdma->of_dma_data; if (!info || !info->filter_fn) return NULL; if (count != 1) return NULL; return __dma_request_channel(&info->dma_cap, info->filter_fn, &dma_spec->args[0], dma_spec->np); } EXPORT_SYMBOL_GPL(of_dma_simple_xlate); /** * of_dma_xlate_by_chan_id - Translate dt property to DMA channel by channel id * @dma_spec: pointer to DMA specifier as found in the device tree * @of_dma: pointer to DMA controller data * * This function can be used as the of xlate callback for DMA driver which wants * to match the channel based on the channel id. When using this xlate function * the #dma-cells propety of the DMA controller dt node needs to be set to 1. * The data parameter of of_dma_controller_register must be a pointer to the * dma_device struct the function should match upon. * * Returns pointer to appropriate dma channel on success or NULL on error. */ struct dma_chan *of_dma_xlate_by_chan_id(struct of_phandle_args *dma_spec, struct of_dma *ofdma) { struct dma_device *dev = ofdma->of_dma_data; struct dma_chan *chan, *candidate = NULL; if (!dev || dma_spec->args_count != 1) return NULL; list_for_each_entry(chan, &dev->channels, device_node) if (chan->chan_id == dma_spec->args[0]) { candidate = chan; break; } if (!candidate) return NULL; return dma_get_slave_channel(candidate); } EXPORT_SYMBOL_GPL(of_dma_xlate_by_chan_id);
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