[PATCH 3/6] usb: add a HCD_DMA flag instead of guestimating DMA capabilities

From: Christoph Hellwig
Date: Sun Aug 11 2019 - 04:06:18 EST

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The usb core is the only major place in the kernel that checks for
a non-NULL device dma_mask to see if a device is DMA capable. This
is generally a bad idea, as all major busses always set up a DMA mask,
even if the device is not DMA capable - in fact bus layers like PCI
can't even know if a device is DMA capable at enumeration time. This
leads to lots of workaround in HCD drivers, and also prevented us from
setting up a DMA mask for platform devices by default last time we
tried.

Replace this guess with an explicit HCD_DMA that is set by drivers that
appear to have DMA support.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
drivers/staging/octeon-usb/octeon-hcd.c | 2 +-
drivers/usb/core/hcd.c | 1 -
drivers/usb/dwc2/hcd.c | 6 +++---
drivers/usb/host/ehci-grlib.c | 2 +-
drivers/usb/host/ehci-hcd.c | 2 +-
drivers/usb/host/ehci-pmcmsp.c | 2 +-
drivers/usb/host/ehci-ppc-of.c | 2 +-
drivers/usb/host/ehci-ps3.c | 2 +-
drivers/usb/host/ehci-sh.c | 2 +-
drivers/usb/host/ehci-xilinx-of.c | 2 +-
drivers/usb/host/fhci-hcd.c | 2 +-
drivers/usb/host/fotg210-hcd.c | 2 +-
drivers/usb/host/imx21-hcd.c | 2 +-
drivers/usb/host/isp116x-hcd.c | 6 ------
drivers/usb/host/isp1362-hcd.c | 5 -----
drivers/usb/host/ohci-hcd.c | 2 +-
drivers/usb/host/ohci-ppc-of.c | 2 +-
drivers/usb/host/ohci-ps3.c | 2 +-
drivers/usb/host/ohci-sa1111.c | 2 +-
drivers/usb/host/ohci-sm501.c | 2 +-
drivers/usb/host/ohci-tmio.c | 2 +-
drivers/usb/host/oxu210hp-hcd.c | 3 ---
drivers/usb/host/r8a66597-hcd.c | 6 ------
drivers/usb/host/sl811-hcd.c | 6 ------
drivers/usb/host/u132-hcd.c | 2 --
drivers/usb/host/uhci-grlib.c | 2 +-
drivers/usb/host/uhci-pci.c | 2 +-
drivers/usb/host/uhci-platform.c | 2 +-
drivers/usb/host/xhci.c | 2 +-
drivers/usb/isp1760/isp1760-core.c | 3 ---
drivers/usb/isp1760/isp1760-if.c | 1 -
drivers/usb/musb/musb_host.c | 2 +-
drivers/usb/renesas_usbhs/mod_host.c | 2 +-
include/linux/usb.h | 1 -
include/linux/usb/hcd.h | 7 +++++--
35 files changed, 31 insertions(+), 62 deletions(-)

diff --git a/drivers/staging/octeon-usb/octeon-hcd.c b/drivers/staging/octeon-usb/octeon-hcd.c
index cd2b777073c4..a5321cc692c5 100644
--- a/drivers/staging/octeon-usb/octeon-hcd.c
+++ b/drivers/staging/octeon-usb/octeon-hcd.c
@@ -3512,7 +3512,7 @@ static const struct hc_driver octeon_hc_driver = {
.product_desc = "Octeon Host Controller",
.hcd_priv_size = sizeof(struct octeon_hcd),
.irq = octeon_usb_irq,
- .flags = HCD_MEMORY | HCD_USB2,
+ .flags = HCD_MEMORY | HCD_DMA | HCD_USB2,
.start = octeon_usb_start,
.stop = octeon_usb_stop,
.urb_enqueue = octeon_usb_urb_enqueue,
diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
index 8592c0344fe8..add2af4af766 100644
--- a/drivers/usb/core/hcd.c
+++ b/drivers/usb/core/hcd.c
@@ -2454,7 +2454,6 @@ struct usb_hcd *__usb_create_hcd(const struct hc_driver *driver,
hcd->self.controller = dev;
hcd->self.sysdev = sysdev;
hcd->self.bus_name = bus_name;
- hcd->self.uses_dma = (sysdev->dma_mask != NULL);

timer_setup(&hcd->rh_timer, rh_timer_func, 0);
#ifdef CONFIG_PM
diff --git a/drivers/usb/dwc2/hcd.c b/drivers/usb/dwc2/hcd.c
index 111787a137ee..81afe553aa66 100644
--- a/drivers/usb/dwc2/hcd.c
+++ b/drivers/usb/dwc2/hcd.c
@@ -5062,13 +5062,13 @@ int dwc2_hcd_init(struct dwc2_hsotg *hsotg)
dwc2_hc_driver.reset_device = dwc2_reset_device;
}

+ if (hsotg->params.host_dma)
+ dwc2_hc_driver.flags |= HCD_DMA;
+
hcd = usb_create_hcd(&dwc2_hc_driver, hsotg->dev, dev_name(hsotg->dev));
if (!hcd)
goto error1;

- if (!hsotg->params.host_dma)
- hcd->self.uses_dma = 0;
-
hcd->has_tt = 1;

res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
diff --git a/drivers/usb/host/ehci-grlib.c b/drivers/usb/host/ehci-grlib.c
index 656b8c08efc8..a2c3b4ec8a8b 100644
--- a/drivers/usb/host/ehci-grlib.c
+++ b/drivers/usb/host/ehci-grlib.c
@@ -30,7 +30,7 @@ static const struct hc_driver ehci_grlib_hc_driver = {
* generic hardware linkage
*/
.irq = ehci_irq,
- .flags = HCD_MEMORY | HCD_USB2 | HCD_BH,
+ .flags = HCD_MEMORY | HCD_DMA | HCD_USB2 | HCD_BH,

/*
* basic lifecycle operations
diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c
index 9da7e22848c9..cf2b7ae93b7e 100644
--- a/drivers/usb/host/ehci-hcd.c
+++ b/drivers/usb/host/ehci-hcd.c
@@ -1193,7 +1193,7 @@ static const struct hc_driver ehci_hc_driver = {
* generic hardware linkage
*/
.irq = ehci_irq,
- .flags = HCD_MEMORY | HCD_USB2 | HCD_BH,
+ .flags = HCD_MEMORY | HCD_DMA | HCD_USB2 | HCD_BH,

/*
* basic lifecycle operations
diff --git a/drivers/usb/host/ehci-pmcmsp.c b/drivers/usb/host/ehci-pmcmsp.c
index 46e160370d6e..a2b610dbedfc 100644
--- a/drivers/usb/host/ehci-pmcmsp.c
+++ b/drivers/usb/host/ehci-pmcmsp.c
@@ -250,7 +250,7 @@ static const struct hc_driver ehci_msp_hc_driver = {
* generic hardware linkage
*/
.irq = ehci_irq,
- .flags = HCD_MEMORY | HCD_USB2 | HCD_BH,
+ .flags = HCD_MEMORY | HCD_DMA | HCD_USB2 | HCD_BH,

/*
* basic lifecycle operations
diff --git a/drivers/usb/host/ehci-ppc-of.c b/drivers/usb/host/ehci-ppc-of.c
index 576f7d79ad4e..9d17e0695e35 100644
--- a/drivers/usb/host/ehci-ppc-of.c
+++ b/drivers/usb/host/ehci-ppc-of.c
@@ -31,7 +31,7 @@ static const struct hc_driver ehci_ppc_of_hc_driver = {
* generic hardware linkage
*/
.irq = ehci_irq,
- .flags = HCD_MEMORY | HCD_USB2 | HCD_BH,
+ .flags = HCD_MEMORY | HC_DMA | HCD_USB2 | HCD_BH,

/*
* basic lifecycle operations
diff --git a/drivers/usb/host/ehci-ps3.c b/drivers/usb/host/ehci-ps3.c
index 454d8c624a3f..fb52133c3557 100644
--- a/drivers/usb/host/ehci-ps3.c
+++ b/drivers/usb/host/ehci-ps3.c
@@ -59,7 +59,7 @@ static const struct hc_driver ps3_ehci_hc_driver = {
.product_desc = "PS3 EHCI Host Controller",
.hcd_priv_size = sizeof(struct ehci_hcd),
.irq = ehci_irq,
- .flags = HCD_MEMORY | HCD_USB2 | HCD_BH,
+ .flags = HCD_MEMORY | HCD_DMA | HCD_USB2 | HCD_BH,
.reset = ps3_ehci_hc_reset,
.start = ehci_run,
.stop = ehci_stop,
diff --git a/drivers/usb/host/ehci-sh.c b/drivers/usb/host/ehci-sh.c
index a9ee767952c1..6a28fb93b9f1 100644
--- a/drivers/usb/host/ehci-sh.c
+++ b/drivers/usb/host/ehci-sh.c
@@ -33,7 +33,7 @@ static const struct hc_driver ehci_sh_hc_driver = {
* generic hardware linkage
*/
.irq = ehci_irq,
- .flags = HCD_USB2 | HCD_MEMORY | HCD_BH,
+ .flags = HCD_USB2 | HCD_DMA | HCD_MEMORY | HCD_BH,

/*
* basic lifecycle operations
diff --git a/drivers/usb/host/ehci-xilinx-of.c b/drivers/usb/host/ehci-xilinx-of.c
index d2a27578e440..67a6ee8cb5d8 100644
--- a/drivers/usb/host/ehci-xilinx-of.c
+++ b/drivers/usb/host/ehci-xilinx-of.c
@@ -66,7 +66,7 @@ static const struct hc_driver ehci_xilinx_of_hc_driver = {
* generic hardware linkage
*/
.irq = ehci_irq,
- .flags = HCD_MEMORY | HCD_USB2 | HCD_BH,
+ .flags = HCD_MEMORY | HCD_DMA | HCD_USB2 | HCD_BH,

/*
* basic lifecycle operations
diff --git a/drivers/usb/host/fhci-hcd.c b/drivers/usb/host/fhci-hcd.c
index 48fe9e6c2465..04733876c9c6 100644
--- a/drivers/usb/host/fhci-hcd.c
+++ b/drivers/usb/host/fhci-hcd.c
@@ -538,7 +538,7 @@ static const struct hc_driver fhci_driver = {

/* generic hardware linkage */
.irq = fhci_irq,
- .flags = HCD_USB11 | HCD_MEMORY,
+ .flags = HCD_DMA | HCD_USB11 | HCD_MEMORY,

/* basic lifecycle operation */
.start = fhci_start,
diff --git a/drivers/usb/host/fotg210-hcd.c b/drivers/usb/host/fotg210-hcd.c
index 77cc36efae95..8d7ccd032d47 100644
--- a/drivers/usb/host/fotg210-hcd.c
+++ b/drivers/usb/host/fotg210-hcd.c
@@ -5504,7 +5504,7 @@ static const struct hc_driver fotg210_fotg210_hc_driver = {
* generic hardware linkage
*/
.irq = fotg210_irq,
- .flags = HCD_MEMORY | HCD_USB2,
+ .flags = HCD_MEMORY | HCD_DMA | HCD_USB2,

/*
* basic lifecycle operations
diff --git a/drivers/usb/host/imx21-hcd.c b/drivers/usb/host/imx21-hcd.c
index 6e3dad19d369..bd5fcc935e09 100644
--- a/drivers/usb/host/imx21-hcd.c
+++ b/drivers/usb/host/imx21-hcd.c
@@ -1771,7 +1771,7 @@ static const struct hc_driver imx21_hc_driver = {
.product_desc = "IMX21 USB Host Controller",
.hcd_priv_size = sizeof(struct imx21),

- .flags = HCD_USB11,
+ .flags = HCD_DMA | HCD_USB11,
.irq = imx21_irq,

.reset = imx21_hc_reset,
diff --git a/drivers/usb/host/isp116x-hcd.c b/drivers/usb/host/isp116x-hcd.c
index 74da136d322a..a87c0b26279e 100644
--- a/drivers/usb/host/isp116x-hcd.c
+++ b/drivers/usb/host/isp116x-hcd.c
@@ -1581,12 +1581,6 @@ static int isp116x_probe(struct platform_device *pdev)
irq = ires->start;
irqflags = ires->flags & IRQF_TRIGGER_MASK;

- if (pdev->dev.dma_mask) {
- DBG("DMA not supported\n");
- ret = -EINVAL;
- goto err1;
- }
-
if (!request_mem_region(addr->start, 2, hcd_name)) {
ret = -EBUSY;
goto err1;
diff --git a/drivers/usb/host/isp1362-hcd.c b/drivers/usb/host/isp1362-hcd.c
index 28bf8bfb091e..96f8daa11f25 100644
--- a/drivers/usb/host/isp1362-hcd.c
+++ b/drivers/usb/host/isp1362-hcd.c
@@ -2645,11 +2645,6 @@ static int isp1362_probe(struct platform_device *pdev)
if (pdev->num_resources < 3)
return -ENODEV;

- if (pdev->dev.dma_mask) {
- DBG(1, "won't do DMA");
- return -ENODEV;
- }
-
irq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
if (!irq_res)
return -ENODEV;
diff --git a/drivers/usb/host/ohci-hcd.c b/drivers/usb/host/ohci-hcd.c
index b457fdaff297..1eb8d17e19db 100644
--- a/drivers/usb/host/ohci-hcd.c
+++ b/drivers/usb/host/ohci-hcd.c
@@ -1178,7 +1178,7 @@ static const struct hc_driver ohci_hc_driver = {
* generic hardware linkage
*/
.irq = ohci_irq,
- .flags = HCD_MEMORY | HCD_USB11,
+ .flags = HCD_MEMORY | HCD_DMA | HCD_USB11,

/*
* basic lifecycle operations
diff --git a/drivers/usb/host/ohci-ppc-of.c b/drivers/usb/host/ohci-ppc-of.c
index 76a9b40b08f1..45f7cceb6df3 100644
--- a/drivers/usb/host/ohci-ppc-of.c
+++ b/drivers/usb/host/ohci-ppc-of.c
@@ -50,7 +50,7 @@ static const struct hc_driver ohci_ppc_of_hc_driver = {
* generic hardware linkage
*/
.irq = ohci_irq,
- .flags = HCD_USB11 | HCD_MEMORY,
+ .flags = HCD_USB11 | HCD_DMA | HCD_MEMORY,

/*
* basic lifecycle operations
diff --git a/drivers/usb/host/ohci-ps3.c b/drivers/usb/host/ohci-ps3.c
index 395f9d3bc849..f77cd6af0ccf 100644
--- a/drivers/usb/host/ohci-ps3.c
+++ b/drivers/usb/host/ohci-ps3.c
@@ -46,7 +46,7 @@ static const struct hc_driver ps3_ohci_hc_driver = {
.product_desc = "PS3 OHCI Host Controller",
.hcd_priv_size = sizeof(struct ohci_hcd),
.irq = ohci_irq,
- .flags = HCD_MEMORY | HCD_USB11,
+ .flags = HCD_MEMORY | HCD_DMA | HCD_USB11,
.reset = ps3_ohci_hc_reset,
.start = ps3_ohci_hc_start,
.stop = ohci_stop,
diff --git a/drivers/usb/host/ohci-sa1111.c b/drivers/usb/host/ohci-sa1111.c
index ebec9a7699e3..8e19a5eb5b62 100644
--- a/drivers/usb/host/ohci-sa1111.c
+++ b/drivers/usb/host/ohci-sa1111.c
@@ -84,7 +84,7 @@ static const struct hc_driver ohci_sa1111_hc_driver = {
* generic hardware linkage
*/
.irq = ohci_irq,
- .flags = HCD_USB11 | HCD_MEMORY,
+ .flags = HCD_USB11 | HCD_DMA | HCD_MEMORY,

/*
* basic lifecycle operations
diff --git a/drivers/usb/host/ohci-sm501.c b/drivers/usb/host/ohci-sm501.c
index c158cda9e4b9..0b2aea6e28d4 100644
--- a/drivers/usb/host/ohci-sm501.c
+++ b/drivers/usb/host/ohci-sm501.c
@@ -49,7 +49,7 @@ static const struct hc_driver ohci_sm501_hc_driver = {
* generic hardware linkage
*/
.irq = ohci_irq,
- .flags = HCD_USB11 | HCD_MEMORY,
+ .flags = HCD_USB11 | HCD_DMA | HCD_MEMORY,

/*
* basic lifecycle operations
diff --git a/drivers/usb/host/ohci-tmio.c b/drivers/usb/host/ohci-tmio.c
index d5a293a707b6..8edbacd3eb17 100644
--- a/drivers/usb/host/ohci-tmio.c
+++ b/drivers/usb/host/ohci-tmio.c
@@ -153,7 +153,7 @@ static const struct hc_driver ohci_tmio_hc_driver = {

/* generic hardware linkage */
.irq = ohci_irq,
- .flags = HCD_USB11 | HCD_MEMORY,
+ .flags = HCD_USB11 | HCD_DMA | HCD_MEMORY,

/* basic lifecycle operations */
.start = ohci_tmio_start,
diff --git a/drivers/usb/host/oxu210hp-hcd.c b/drivers/usb/host/oxu210hp-hcd.c
index 47c5515a9ce4..29a49cc8a1ed 100644
--- a/drivers/usb/host/oxu210hp-hcd.c
+++ b/drivers/usb/host/oxu210hp-hcd.c
@@ -2649,9 +2649,6 @@ static int oxu_reset(struct usb_hcd *hcd)
INIT_LIST_HEAD(&oxu->urb_list);
oxu->urb_len = 0;

- /* FIMXE */
- hcd->self.controller->dma_mask = NULL;
-
if (oxu->is_otg) {
oxu->caps = hcd->regs + OXU_OTG_CAP_OFFSET;
oxu->regs = hcd->regs + OXU_OTG_CAP_OFFSET + \
diff --git a/drivers/usb/host/r8a66597-hcd.c b/drivers/usb/host/r8a66597-hcd.c
index 42668aeca57c..0c03ac6b0213 100644
--- a/drivers/usb/host/r8a66597-hcd.c
+++ b/drivers/usb/host/r8a66597-hcd.c
@@ -2411,12 +2411,6 @@ static int r8a66597_probe(struct platform_device *pdev)
if (usb_disabled())
return -ENODEV;

- if (pdev->dev.dma_mask) {
- ret = -EINVAL;
- dev_err(&pdev->dev, "dma not supported\n");
- goto clean_up;
- }
-
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res) {
ret = -ENODEV;
diff --git a/drivers/usb/host/sl811-hcd.c b/drivers/usb/host/sl811-hcd.c
index 5b061e599948..72a34a1eb618 100644
--- a/drivers/usb/host/sl811-hcd.c
+++ b/drivers/usb/host/sl811-hcd.c
@@ -1632,12 +1632,6 @@ sl811h_probe(struct platform_device *dev)
irq = ires->start;
irqflags = ires->flags & IRQF_TRIGGER_MASK;

- /* refuse to confuse usbcore */
- if (dev->dev.dma_mask) {
- dev_dbg(&dev->dev, "no we won't dma\n");
- return -EINVAL;
- }
-
/* the chip may be wired for either kind of addressing */
addr = platform_get_resource(dev, IORESOURCE_MEM, 0);
data = platform_get_resource(dev, IORESOURCE_MEM, 1);
diff --git a/drivers/usb/host/u132-hcd.c b/drivers/usb/host/u132-hcd.c
index 400c40bc43a6..4efee34f154f 100644
--- a/drivers/usb/host/u132-hcd.c
+++ b/drivers/usb/host/u132-hcd.c
@@ -3077,8 +3077,6 @@ static int u132_probe(struct platform_device *pdev)
retval = ftdi_read_pcimem(pdev, roothub.a, &rh_a);
if (retval)
return retval;
- if (pdev->dev.dma_mask)
- return -EINVAL;

hcd = usb_create_hcd(&u132_hc_driver, &pdev->dev, dev_name(&pdev->dev));
if (!hcd) {
diff --git a/drivers/usb/host/uhci-grlib.c b/drivers/usb/host/uhci-grlib.c
index 2103b1ed0f8f..0a201a73b196 100644
--- a/drivers/usb/host/uhci-grlib.c
+++ b/drivers/usb/host/uhci-grlib.c
@@ -63,7 +63,7 @@ static const struct hc_driver uhci_grlib_hc_driver = {

/* Generic hardware linkage */
.irq = uhci_irq,
- .flags = HCD_MEMORY | HCD_USB11,
+ .flags = HCD_MEMORY | HCD_DMA | HCD_USB11,

/* Basic lifecycle operations */
.reset = uhci_grlib_init,
diff --git a/drivers/usb/host/uhci-pci.c b/drivers/usb/host/uhci-pci.c
index 0dd944277c99..0fa3d72bae26 100644
--- a/drivers/usb/host/uhci-pci.c
+++ b/drivers/usb/host/uhci-pci.c
@@ -261,7 +261,7 @@ static const struct hc_driver uhci_driver = {

/* Generic hardware linkage */
.irq = uhci_irq,
- .flags = HCD_USB11,
+ .flags = HCD_DMA | HCD_USB11,

/* Basic lifecycle operations */
.reset = uhci_pci_init,
diff --git a/drivers/usb/host/uhci-platform.c b/drivers/usb/host/uhci-platform.c
index 89700e26fb29..70dbd95c3f06 100644
--- a/drivers/usb/host/uhci-platform.c
+++ b/drivers/usb/host/uhci-platform.c
@@ -41,7 +41,7 @@ static const struct hc_driver uhci_platform_hc_driver = {

/* Generic hardware linkage */
.irq = uhci_irq,
- .flags = HCD_MEMORY | HCD_USB11,
+ .flags = HCD_MEMORY | HCD_DMA | HCD_USB11,

/* Basic lifecycle operations */
.reset = uhci_platform_init,
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 03d1e552769b..e315c0158e90 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -5217,7 +5217,7 @@ static const struct hc_driver xhci_hc_driver = {
* generic hardware linkage
*/
.irq = xhci_irq,
- .flags = HCD_MEMORY | HCD_USB3 | HCD_SHARED,
+ .flags = HCD_MEMORY | HCD_DMA | HCD_USB3 | HCD_SHARED,

/*
* basic lifecycle operations
diff --git a/drivers/usb/isp1760/isp1760-core.c b/drivers/usb/isp1760/isp1760-core.c
index 55b94fd10331..fdeb4cf97cc5 100644
--- a/drivers/usb/isp1760/isp1760-core.c
+++ b/drivers/usb/isp1760/isp1760-core.c
@@ -120,9 +120,6 @@ int isp1760_register(struct resource *mem, int irq, unsigned long irqflags,
(!IS_ENABLED(CONFIG_USB_ISP1761_UDC) || udc_disabled))
return -ENODEV;

- /* prevent usb-core allocating DMA pages */
- dev->dma_mask = NULL;
-
isp = devm_kzalloc(dev, sizeof(*isp), GFP_KERNEL);
if (!isp)
return -ENOMEM;
diff --git a/drivers/usb/isp1760/isp1760-if.c b/drivers/usb/isp1760/isp1760-if.c
index 241a00d75027..07cc82ff327c 100644
--- a/drivers/usb/isp1760/isp1760-if.c
+++ b/drivers/usb/isp1760/isp1760-if.c
@@ -139,7 +139,6 @@ static int isp1761_pci_probe(struct pci_dev *dev,

pci_set_master(dev);

- dev->dev.dma_mask = NULL;
ret = isp1760_register(&dev->resource[3], dev->irq, 0, &dev->dev,
devflags);
if (ret < 0)
diff --git a/drivers/usb/musb/musb_host.c b/drivers/usb/musb/musb_host.c
index eb308ec35c66..5a44b70372d9 100644
--- a/drivers/usb/musb/musb_host.c
+++ b/drivers/usb/musb/musb_host.c
@@ -2689,7 +2689,7 @@ static const struct hc_driver musb_hc_driver = {
.description = "musb-hcd",
.product_desc = "MUSB HDRC host driver",
.hcd_priv_size = sizeof(struct musb *),
- .flags = HCD_USB2 | HCD_MEMORY,
+ .flags = HCD_USB2 | HCD_DMA | HCD_MEMORY,

/* not using irq handler or reset hooks from usbcore, since
* those must be shared with peripheral code for OTG configs
diff --git a/drivers/usb/renesas_usbhs/mod_host.c b/drivers/usb/renesas_usbhs/mod_host.c
index ddd3be48f948..ae54221011c3 100644
--- a/drivers/usb/renesas_usbhs/mod_host.c
+++ b/drivers/usb/renesas_usbhs/mod_host.c
@@ -1283,7 +1283,7 @@ static const struct hc_driver usbhsh_driver = {
/*
* generic hardware linkage
*/
- .flags = HCD_USB2,
+ .flags = HCD_DMA | HCD_USB2,

.start = usbhsh_host_start,
.stop = usbhsh_host_stop,
diff --git a/include/linux/usb.h b/include/linux/usb.h
index e87826e23d59..85a8865f9e83 100644
--- a/include/linux/usb.h
+++ b/include/linux/usb.h
@@ -426,7 +426,6 @@ struct usb_bus {
struct device *sysdev; /* as seen from firmware or bus */
int busnum; /* Bus number (in order of reg) */
const char *bus_name; /* stable id (PCI slot_name etc) */
- u8 uses_dma; /* Does the host controller use DMA? */
u8 uses_pio_for_control; /*
* Does the host controller use PIO
* for control transfers?
diff --git a/include/linux/usb/hcd.h b/include/linux/usb/hcd.h
index a20e7815d814..8d3869c7de85 100644
--- a/include/linux/usb/hcd.h
+++ b/include/linux/usb/hcd.h
@@ -256,6 +256,7 @@ struct hc_driver {

int flags;
#define HCD_MEMORY 0x0001 /* HC regs use memory (else I/O) */
+#define HCD_DMA 0x0002 /* HC uses DMA */
#define HCD_SHARED 0x0004 /* Two (or more) usb_hcds share HW */
#define HCD_USB11 0x0010 /* USB 1.1 */
#define HCD_USB2 0x0020 /* USB 2.0 */
@@ -422,8 +423,10 @@ static inline bool hcd_periodic_completion_in_progress(struct usb_hcd *hcd,
return hcd->high_prio_bh.completing_ep == ep;
}

-#define hcd_uses_dma(hcd) \
- (IS_ENABLED(CONFIG_HAS_DMA) && (hcd)->self.uses_dma)
+static inline bool hcd_uses_dma(struct usb_hcd *hcd)
+{
+ return IS_ENABLED(CONFIG_HAS_DMA) && (hcd->driver->flags & HCD_DMA);
+}

extern int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb);
extern int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb,
--
2.20.1

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