Commit fc15be39 authored by Alexandru Ardelean's avatar Alexandru Ardelean Committed by Vinod Koul
Browse files

dmaengine: axi-dmac: add regmap support 

The registers for AXI DMAC are detailed at:
  https://wiki.analog.com/resources/fpga/docs/axi_dmac#register_map



This change adds regmap support for these registers, in case some wants to
have a more direct access to them via this interface.

Signed-off-by: default avatarAlexandru Ardelean <alexandru.ardelean@analog.com>
[vkoul: fixed code style issue]
Signed-off-by: default avatarVinod Koul <vkoul@kernel.org>
parent e28d9155

drivers/dma/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -102,6 +102,7 @@ config AXI_DMAC 
	depends on MICROBLAZE || NIOS2 || ARCH_ZYNQ || ARCH_ZYNQMP || ARCH_SOCFPGA || COMPILE_TEST

	select DMA_ENGINE

	select DMA_VIRTUAL_CHANNELS

	select REGMAP_MMIO

	help

	  Enable support for the Analog Devices AXI-DMAC peripheral. This DMA

	  controller is often used in Analog Device's reference designs for FPGA

drivers/dma/dma-axi-dmac.c

+41 −0
Original line number Diff line number Diff line
@@ -18,6 +18,7 @@ 
#include <linux/of.h>

#include <linux/of_dma.h>

#include <linux/platform_device.h>

#include <linux/regmap.h>

#include <linux/slab.h>

#include <linux/fpga/adi-axi-common.h>
@@ -678,6 +679,44 @@ static void axi_dmac_desc_free(struct virt_dma_desc *vdesc) 
	kfree(container_of(vdesc, struct axi_dmac_desc, vdesc));

}



static bool axi_dmac_regmap_rdwr(struct device *dev, unsigned int reg)

{

	switch (reg) {

	case AXI_DMAC_REG_IRQ_MASK:

	case AXI_DMAC_REG_IRQ_SOURCE:

	case AXI_DMAC_REG_IRQ_PENDING:

	case AXI_DMAC_REG_CTRL:

	case AXI_DMAC_REG_TRANSFER_ID:

	case AXI_DMAC_REG_START_TRANSFER:

	case AXI_DMAC_REG_FLAGS:

	case AXI_DMAC_REG_DEST_ADDRESS:

	case AXI_DMAC_REG_SRC_ADDRESS:

	case AXI_DMAC_REG_X_LENGTH:

	case AXI_DMAC_REG_Y_LENGTH:

	case AXI_DMAC_REG_DEST_STRIDE:

	case AXI_DMAC_REG_SRC_STRIDE:

	case AXI_DMAC_REG_TRANSFER_DONE:

	case AXI_DMAC_REG_ACTIVE_TRANSFER_ID:

	case AXI_DMAC_REG_STATUS:

	case AXI_DMAC_REG_CURRENT_SRC_ADDR:

	case AXI_DMAC_REG_CURRENT_DEST_ADDR:

	case AXI_DMAC_REG_PARTIAL_XFER_LEN:

	case AXI_DMAC_REG_PARTIAL_XFER_ID:

		return true;

	default:

		return false;

	}

}



static const struct regmap_config axi_dmac_regmap_config = {

	.reg_bits = 32,

	.val_bits = 32,

	.reg_stride = 4,

	.max_register = AXI_DMAC_REG_PARTIAL_XFER_ID,

	.readable_reg = axi_dmac_regmap_rdwr,

	.writeable_reg = axi_dmac_regmap_rdwr,

};



/*

 * The configuration stored in the devicetree matches the configuration

 * parameters of the peripheral instance and allows the driver to know which
@@ -882,6 +921,8 @@ static int axi_dmac_probe(struct platform_device *pdev) 


	platform_set_drvdata(pdev, dmac);



	devm_regmap_init_mmio(&pdev->dev, dmac->base, &axi_dmac_regmap_config);



	return 0;



err_unregister_of:

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