Unverified Commit b9b1eae7 authored by Sanket Parmar's avatar Sanket Parmar Committed by Peter Chen
Browse files

usb: cdns3: Use dma_pool_* api to alloc trb pool 



Allocation of DMA coherent memory in atomic context using
dma_alloc_coherent() might fail on platforms with smaller
DMA region.

To fix it, dma_alloc_coherent() is replaced with dma_pool
API to allocate a smaller chunk of DMA coherent memory for
TRB rings.

Reported-by: default avatarAswath Govindraju <a-govindraju@ti.com>
Signed-off-by: default avatarSanket Parmar <sparmar@cadence.com>
Signed-off-by: default avatarPeter Chen <peter.chen@kernel.org>
parent 575dd7ec

drivers/usb/cdns3/cdns3-gadget.c

+19 −23
Original line number Diff line number Diff line
@@ -59,6 +59,7 @@ 
#include <linux/dma-mapping.h>

#include <linux/usb/gadget.h>

#include <linux/module.h>

#include <linux/dmapool.h>

#include <linux/iopoll.h>



#include "core.h"
@@ -190,28 +191,12 @@ dma_addr_t cdns3_trb_virt_to_dma(struct cdns3_endpoint *priv_ep, 
	return priv_ep->trb_pool_dma + offset;

}



static int cdns3_ring_size(struct cdns3_endpoint *priv_ep)

{

	switch (priv_ep->type) {

	case USB_ENDPOINT_XFER_ISOC:

		return TRB_ISO_RING_SIZE;

	case USB_ENDPOINT_XFER_CONTROL:

		return TRB_CTRL_RING_SIZE;

	default:

		if (priv_ep->use_streams)

			return TRB_STREAM_RING_SIZE;

		else

			return TRB_RING_SIZE;

	}

}



static void cdns3_free_trb_pool(struct cdns3_endpoint *priv_ep)

{

	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;



	if (priv_ep->trb_pool) {

		dma_free_coherent(priv_dev->sysdev,

				  cdns3_ring_size(priv_ep),

		dma_pool_free(priv_dev->eps_dma_pool,

			      priv_ep->trb_pool, priv_ep->trb_pool_dma);

		priv_ep->trb_pool = NULL;

	}
@@ -226,7 +211,7 @@ static void cdns3_free_trb_pool(struct cdns3_endpoint *priv_ep) 
int cdns3_allocate_trb_pool(struct cdns3_endpoint *priv_ep)

{

	struct cdns3_device *priv_dev = priv_ep->cdns3_dev;

	int ring_size = cdns3_ring_size(priv_ep);

	int ring_size = TRB_RING_SIZE;

	int num_trbs = ring_size / TRB_SIZE;

	struct cdns3_trb *link_trb;
@@ -234,10 +219,10 @@ int cdns3_allocate_trb_pool(struct cdns3_endpoint *priv_ep) 
		cdns3_free_trb_pool(priv_ep);



	if (!priv_ep->trb_pool) {

		priv_ep->trb_pool = dma_alloc_coherent(priv_dev->sysdev,

						       ring_size,

						       &priv_ep->trb_pool_dma,

						       GFP_DMA32 | GFP_ATOMIC);

		priv_ep->trb_pool = dma_pool_alloc(priv_dev->eps_dma_pool,

						   GFP_DMA32 | GFP_ATOMIC,

						   &priv_ep->trb_pool_dma);



		if (!priv_ep->trb_pool)

			return -ENOMEM;
@@ -3113,6 +3098,7 @@ static void cdns3_gadget_exit(struct cdns *cdns) 


	dma_free_coherent(priv_dev->sysdev, 8, priv_dev->setup_buf,

			  priv_dev->setup_dma);

	dma_pool_destroy(priv_dev->eps_dma_pool);



	kfree(priv_dev->zlp_buf);

	usb_put_gadget(&priv_dev->gadget);
@@ -3185,6 +3171,14 @@ static int cdns3_gadget_start(struct cdns *cdns) 
	/* initialize endpoint container */

	INIT_LIST_HEAD(&priv_dev->gadget.ep_list);

	INIT_LIST_HEAD(&priv_dev->aligned_buf_list);

	priv_dev->eps_dma_pool = dma_pool_create("cdns3_eps_dma_pool",

						 priv_dev->sysdev,

						 TRB_RING_SIZE, 8, 0);

	if (!priv_dev->eps_dma_pool) {

		dev_err(priv_dev->dev, "Failed to create TRB dma pool\n");

		ret = -ENOMEM;

		goto err1;

	}



	ret = cdns3_init_eps(priv_dev);

	if (ret) {
@@ -3235,6 +3229,8 @@ static int cdns3_gadget_start(struct cdns *cdns) 
err2:

	cdns3_free_all_eps(priv_dev);

err1:

	dma_pool_destroy(priv_dev->eps_dma_pool);



	usb_put_gadget(&priv_dev->gadget);

	cdns->gadget_dev = NULL;

	return ret;

drivers/usb/cdns3/cdns3-gadget.h

+1 −0
Original line number Diff line number Diff line
@@ -1298,6 +1298,7 @@ struct cdns3_device { 


	struct cdns3_usb_regs		__iomem *regs;



	struct dma_pool			*eps_dma_pool;

	struct usb_ctrlrequest		*setup_buf;

	dma_addr_t			setup_dma;

	void				*zlp_buf;