usb: chipidea: tegra: Support host mode

Add USB host mode to the Tegra HDRC driver. This allows us to benefit from
support provided by the generic ChipIdea driver instead of duplicating the
effort in a separate ehci-tegra driver.

Tested-by: Matt Merhar <mattmerhar@protonmail.com>
Tested-by: Nicolas Chauvet <kwizart@gmail.com>
Tested-by: Ion Agorria <ion@agorria.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Peter Chen <peter.chen@kernel.org>
Signed-off-by: Peter Geis <pgwipeout@gmail.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Link: https://lore.kernel.org/r/20201218120246.7759-6-digetx@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 102 insertions, 2 deletions

diff --git a/drivers/usb/chipidea/host.c b/drivers/usb/chipidea/host.c
index 48e4a5ca1835..67247d2ac07a 100644
--- a/drivers/usb/chipidea/host.c
+++ b/drivers/usb/chipidea/host.c
@@ -29,6 +29,12 @@ struct ehci_ci_priv {
 	bool enabled;
 };
 
+struct ci_hdrc_dma_aligned_buffer {
+	void *kmalloc_ptr;
+	void *old_xfer_buffer;
+	u8 data[0];
+};
+
 static int ehci_ci_portpower(struct usb_hcd *hcd, int portnum, bool enable)
 {
 	struct ehci_hcd *ehci = hcd_to_ehci(hcd);
@@ -160,14 +166,15 @@ static int host_start(struct ci_hdrc *ci)
 		pinctrl_select_state(ci->platdata->pctl,
 				     ci->platdata->pins_host);
 
+	ci->hcd = hcd;
+
 	ret = usb_add_hcd(hcd, 0, 0);
 	if (ret) {
+		ci->hcd = NULL;
 		goto disable_reg;
 	} else {
 		struct usb_otg *otg = &ci->otg;
 
-		ci->hcd = hcd;
-
 		if (ci_otg_is_fsm_mode(ci)) {
 			otg->host = &hcd->self;
 			hcd->self.otg_port = 1;
@@ -237,6 +244,7 @@ static int ci_ehci_hub_control(
 	u32		temp;
 	unsigned long	flags;
 	int		retval = 0;
+	bool		done = false;
 	struct device *dev = hcd->self.controller;
 	struct ci_hdrc *ci = dev_get_drvdata(dev);
 
@@ -244,6 +252,13 @@ static int ci_ehci_hub_control(
 
 	spin_lock_irqsave(&ehci->lock, flags);
 
+	if (ci->platdata->hub_control) {
+		retval = ci->platdata->hub_control(ci, typeReq, wValue, wIndex,
+						   buf, wLength, &done, &flags);
+		if (done)
+			goto done;
+	}
+
 	if (typeReq == SetPortFeature && wValue == USB_PORT_FEAT_SUSPEND) {
 		temp = ehci_readl(ehci, status_reg);
 		if ((temp & PORT_PE) == 0 || (temp & PORT_RESET) != 0) {
@@ -349,6 +364,86 @@ static int ci_ehci_bus_suspend(struct usb_hcd *hcd)
 	return 0;
 }
 
+static void ci_hdrc_free_dma_aligned_buffer(struct urb *urb)
+{
+	struct ci_hdrc_dma_aligned_buffer *temp;
+	size_t length;
+
+	if (!(urb->transfer_flags & URB_ALIGNED_TEMP_BUFFER))
+		return;
+
+	temp = container_of(urb->transfer_buffer,
+			    struct ci_hdrc_dma_aligned_buffer, data);
+
+	if (usb_urb_dir_in(urb)) {
+		if (usb_pipeisoc(urb->pipe))
+			length = urb->transfer_buffer_length;
+		else
+			length = urb->actual_length;
+
+		memcpy(temp->old_xfer_buffer, temp->data, length);
+	}
+	urb->transfer_buffer = temp->old_xfer_buffer;
+	kfree(temp->kmalloc_ptr);
+
+	urb->transfer_flags &= ~URB_ALIGNED_TEMP_BUFFER;
+}
+
+static int ci_hdrc_alloc_dma_aligned_buffer(struct urb *urb, gfp_t mem_flags)
+{
+	struct ci_hdrc_dma_aligned_buffer *temp, *kmalloc_ptr;
+	const unsigned int ci_hdrc_usb_dma_align = 32;
+	size_t kmalloc_size;
+
+	if (urb->num_sgs || urb->sg || urb->transfer_buffer_length == 0 ||
+	    !((uintptr_t)urb->transfer_buffer & (ci_hdrc_usb_dma_align - 1)))
+		return 0;
+
+	/* Allocate a buffer with enough padding for alignment */
+	kmalloc_size = urb->transfer_buffer_length +
+		       sizeof(struct ci_hdrc_dma_aligned_buffer) +
+		       ci_hdrc_usb_dma_align - 1;
+
+	kmalloc_ptr = kmalloc(kmalloc_size, mem_flags);
+	if (!kmalloc_ptr)
+		return -ENOMEM;
+
+	/* Position our struct dma_aligned_buffer such that data is aligned */
+	temp = PTR_ALIGN(kmalloc_ptr + 1, ci_hdrc_usb_dma_align) - 1;
+	temp->kmalloc_ptr = kmalloc_ptr;
+	temp->old_xfer_buffer = urb->transfer_buffer;
+	if (usb_urb_dir_out(urb))
+		memcpy(temp->data, urb->transfer_buffer,
+		       urb->transfer_buffer_length);
+	urb->transfer_buffer = temp->data;
+
+	urb->transfer_flags |= URB_ALIGNED_TEMP_BUFFER;
+
+	return 0;
+}
+
+static int ci_hdrc_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
+				   gfp_t mem_flags)
+{
+	int ret;
+
+	ret = ci_hdrc_alloc_dma_aligned_buffer(urb, mem_flags);
+	if (ret)
+		return ret;
+
+	ret = usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
+	if (ret)
+		ci_hdrc_free_dma_aligned_buffer(urb);
+
+	return ret;
+}
+
+static void ci_hdrc_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
+{
+	usb_hcd_unmap_urb_for_dma(hcd, urb);
+	ci_hdrc_free_dma_aligned_buffer(urb);
+}
+
 int ci_hdrc_host_init(struct ci_hdrc *ci)
 {
 	struct ci_role_driver *rdrv;
@@ -366,6 +461,11 @@ int ci_hdrc_host_init(struct ci_hdrc *ci)
 	rdrv->name	= "host";
 	ci->roles[CI_ROLE_HOST] = rdrv;
 
+	if (ci->platdata->flags & CI_HDRC_REQUIRES_ALIGNED_DMA) {
+		ci_ehci_hc_driver.map_urb_for_dma = ci_hdrc_map_urb_for_dma;
+		ci_ehci_hc_driver.unmap_urb_for_dma = ci_hdrc_unmap_urb_for_dma;
+	}
+
 	return 0;
 }