diff options
Diffstat (limited to 'drivers/dma/of-dma.c')
| -rw-r--r-- | drivers/dma/of-dma.c | 54 |
1 files changed, 34 insertions, 20 deletions
diff --git a/drivers/dma/of-dma.c b/drivers/dma/of-dma.c index 91fd395c90c4..423442e55d36 100644 --- a/drivers/dma/of-dma.c +++ b/drivers/dma/of-dma.c @@ -1,13 +1,10 @@ +// 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/ - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. */ #include <linux/device.h> @@ -18,6 +15,8 @@ #include <linux/of.h> #include <linux/of_dma.h> +#include "dmaengine.h" + static LIST_HEAD(of_dma_list); static DEFINE_MUTEX(of_dma_lock); @@ -27,10 +26,10 @@ static DEFINE_MUTEX(of_dma_lock); * * 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 + * to the DMA data stored is returned. A NULL pointer is returned if no match is * found. */ -static struct of_dma *of_dma_find_controller(struct of_phandle_args *dma_spec) +static struct of_dma *of_dma_find_controller(const struct of_phandle_args *dma_spec) { struct of_dma *ofdma; @@ -47,7 +46,7 @@ static struct of_dma *of_dma_find_controller(struct of_phandle_args *dma_spec) /** * 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) + * @ofdma: 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 @@ -68,18 +67,33 @@ static struct dma_chan *of_dma_router_xlate(struct of_phandle_args *dma_spec, return NULL; ofdma_target = of_dma_find_controller(&dma_spec_target); - if (!ofdma_target) - return NULL; + if (!ofdma_target) { + ofdma->dma_router->route_free(ofdma->dma_router->dev, + route_data); + chan = ERR_PTR(-EPROBE_DEFER); + goto err; + } chan = ofdma_target->of_dma_xlate(&dma_spec_target, ofdma_target); - if (chan) { - chan->router = ofdma->dma_router; - chan->route_data = route_data; - } else { + if (IS_ERR_OR_NULL(chan)) { ofdma->dma_router->route_free(ofdma->dma_router->dev, route_data); + } else { + int ret = 0; + + chan->router = ofdma->dma_router; + chan->route_data = route_data; + + if (chan->device->device_router_config) + ret = chan->device->device_router_config(chan); + + if (ret) { + dma_release_channel(chan); + chan = ERR_PTR(ret); + } } +err: /* * Need to put the node back since the ofdma->of_dma_route_allocate * has taken it for generating the new, translated dma_spec @@ -93,7 +107,7 @@ static struct dma_chan *of_dma_router_xlate(struct of_phandle_args *dma_spec, * @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 + * @data: pointer to controller specific data to be used by * translation function * * Returns 0 on success or appropriate errno value on error. @@ -250,7 +264,7 @@ struct dma_chan *of_dma_request_slave_channel(struct device_node *np, } /* Silently fail if there is not even the "dmas" property */ - if (!of_find_property(np, "dmas", NULL)) + if (!of_property_present(np, "dmas")) return ERR_PTR(-ENODEV); count = of_property_count_strings(np, "dma-names"); @@ -296,7 +310,7 @@ 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 + * @ofdma: 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. @@ -316,19 +330,19 @@ struct dma_chan *of_dma_simple_xlate(struct of_phandle_args *dma_spec, if (count != 1) return NULL; - return dma_request_channel(info->dma_cap, info->filter_fn, - &dma_spec->args[0]); + 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 + * @ofdma: 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 #dma-cells property 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. * |