[4/5] usb: chipidea: tegra: add the tegra specific bits

diff --git a/drivers/usb/chipidea/tegra.h b/drivers/usb/chipidea/tegra.h
new file mode 100644
index 000000000000..4e61381bbd68
--- /dev/null
+++ b/drivers/usb/chipidea/tegra.h
@@ -0,0 +1,159 @@ 
+/* SPDX-License-Identifier: GPL-2.0+
+ *
+ * Tegra specific bits for Chipidea USB dual role driver
+ *
+ * Pulled from ehci-tegra.c
+ *
+ */
+
+#define TEGRA_USB_DMA_ALIGN 32
+
+struct tegra_dma_aligned_buffer {
+	void *kmalloc_ptr;
+	void *old_xfer_buffer;
+	u8 data[0];
+};
+
+static int tegra_ehci_internal_port_reset(
+	struct ehci_hcd *ehci,
+	u32 __iomem     *portsc_reg
+)
+{
+	u32             temp;
+	unsigned long   flags;
+	int             retval = 0;
+	int             i, tries;
+	u32             saved_usbintr;
+
+	spin_lock_irqsave(&ehci->lock, flags);
+	saved_usbintr = ehci_readl(ehci, &ehci->regs->intr_enable);
+	/* disable USB interrupt */
+	ehci_writel(ehci, 0, &ehci->regs->intr_enable);
+	spin_unlock_irqrestore(&ehci->lock, flags);
+
+	/*
+	 * Here we have to do Port Reset at most twice for
+	 * Port Enable bit to be set.
+	 */
+	for (i = 0; i < 2; i++) {
+		temp = ehci_readl(ehci, portsc_reg);
+		temp |= PORT_RESET;
+		ehci_writel(ehci, temp, portsc_reg);
+		mdelay(10);
+		temp &= ~PORT_RESET;
+		ehci_writel(ehci, temp, portsc_reg);
+		mdelay(1);
+		tries = 100;
+		do {
+			mdelay(1);
+			/*
+			 * Up to this point, Port Enable bit is
+			 * expected to be set after 2 ms waiting.
+			 * USB1 usually takes extra 45 ms, for safety,
+			 * we take 100 ms as timeout.
+			 */
+			temp = ehci_readl(ehci, portsc_reg);
+		} while (!(temp & PORT_PE) && tries--);
+		if (temp & PORT_PE)
+			break;
+	}
+	if (i == 2)
+		retval = -ETIMEDOUT;
+
+	/*
+	 * Clear Connect Status Change bit if it's set.
+	 * We can't clear PORT_PEC. It will also cause PORT_PE to be cleared.
+	 */
+	if (temp & PORT_CSC)
+		ehci_writel(ehci, PORT_CSC, portsc_reg);
+
+	/*
+	 * Write to clear any interrupt status bits that might be set
+	 * during port reset.
+	 */
+	temp = ehci_readl(ehci, &ehci->regs->status);
+	ehci_writel(ehci, temp, &ehci->regs->status);
+
+	/* restore original interrupt enable bits */
+	ehci_writel(ehci, saved_usbintr, &ehci->regs->intr_enable);
+	return retval;
+}
+
+static void tegra_free_dma_aligned_buffer(struct urb *urb)
+{
+	struct tegra_dma_aligned_buffer *temp;
+	size_t length;
+
+	if (!(urb->transfer_flags & URB_ALIGNED_TEMP_BUFFER))
+		return;
+
+	temp = container_of(urb->transfer_buffer,
+		struct tegra_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 tegra_alloc_dma_aligned_buffer(struct urb *urb, gfp_t mem_flags)
+{
+	struct tegra_dma_aligned_buffer *temp, *kmalloc_ptr;
+	size_t kmalloc_size;
+
+	if (urb->num_sgs || urb->sg ||
+		urb->transfer_buffer_length == 0 ||
+		!((uintptr_t)urb->transfer_buffer & (TEGRA_USB_DMA_ALIGN - 1)))
+		return 0;
+
+	/* Allocate a buffer with enough padding for alignment */
+	kmalloc_size = urb->transfer_buffer_length +
+		sizeof(struct tegra_dma_aligned_buffer) + TEGRA_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, TEGRA_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 tegra_ehci_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
+				      gfp_t mem_flags)
+{
+	int ret;
+
+	ret = tegra_alloc_dma_aligned_buffer(urb, mem_flags);
+	if (ret)
+		return ret;
+
+	ret = usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
+	if (ret)
+		tegra_free_dma_aligned_buffer(urb);
+
+	return ret;
+}
+
+static void tegra_ehci_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
+{
+	usb_hcd_unmap_urb_for_dma(hcd, urb);
+	tegra_free_dma_aligned_buffer(urb);
+}