diff options
Diffstat (limited to 'drivers/dma/dw/acpi.c')
-rw-r--r-- | drivers/dma/dw/acpi.c | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/drivers/dma/dw/acpi.c b/drivers/dma/dw/acpi.c new file mode 100644 index 000000000000..f6e8d55b4f6e --- /dev/null +++ b/drivers/dma/dw/acpi.c @@ -0,0 +1,53 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2013,2019 Intel Corporation + +#include <linux/acpi.h> +#include <linux/acpi_dma.h> + +#include "internal.h" + +static bool dw_dma_acpi_filter(struct dma_chan *chan, void *param) +{ + struct acpi_dma_spec *dma_spec = param; + struct dw_dma_slave slave = { + .dma_dev = dma_spec->dev, + .src_id = dma_spec->slave_id, + .dst_id = dma_spec->slave_id, + .m_master = 0, + .p_master = 1, + }; + + return dw_dma_filter(chan, &slave); +} + +void dw_dma_acpi_controller_register(struct dw_dma *dw) +{ + struct device *dev = dw->dma.dev; + struct acpi_dma_filter_info *info; + int ret; + + if (!has_acpi_companion(dev)) + return; + + info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL); + if (!info) + return; + + dma_cap_zero(info->dma_cap); + dma_cap_set(DMA_SLAVE, info->dma_cap); + info->filter_fn = dw_dma_acpi_filter; + + ret = acpi_dma_controller_register(dev, acpi_dma_simple_xlate, info); + if (ret) + dev_err(dev, "could not register acpi_dma_controller\n"); +} + +void dw_dma_acpi_controller_free(struct dw_dma *dw) +{ + struct device *dev = dw->dma.dev; + + if (!has_acpi_companion(dev)) + return; + + acpi_dma_controller_free(dev); +} |