// SPDX-License-Identifier: GPL-2.0+
/*
* aspeed-vhub -- Driver for Aspeed SoC "vHub" USB gadget
*
* core.c - Top level support
*
* Copyright 2017 IBM Corporation
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/delay.h>
#include <linux/ioport.h>
#include <linux/slab.h>
#include <linux/errno.h>
#include <linux/list.h>
#include <linux/interrupt.h>
#include <linux/proc_fs.h>
#include <linux/prefetch.h>
#include <linux/clk.h>
#include <linux/usb/gadget.h>
#include <linux/of.h>
#include <linux/regmap.h>
#include <linux/dma-mapping.h>
#include "vhub.h"
void ast_vhub_done(struct ast_vhub_ep *ep, struct ast_vhub_req *req,
int status)
{
bool internal = req->internal;
struct ast_vhub *vhub = ep->vhub;
EPVDBG(ep, "completing request @%p, status %d\n", req, status);
list_del_init(&req->queue);
if ((req->req.status == -EINPROGRESS) || (status == -EOVERFLOW))
req->req.status = status;
if (req->req.dma) {
if (!WARN_ON(!ep->dev))
usb_gadget_unmap_request_by_dev(&vhub->pdev->dev,
&req->req, ep->epn.is_in);
req->req.dma = 0;
}
/*
* If this isn't an internal EP0 request, call the core
* to call the gadget completion.
*/
if (!internal) {
spin_unlock(&ep->vhub->lock);
usb_gadget_giveback_request(&ep->ep, &req->req);
spin_lock(&ep->vhub->lock);
}
}
void ast_vhub_nuke(struct ast_vhub_ep *ep, int status)
{
struct ast_vhub_req *req;
int count = 0;
/* Beware, lock will be dropped & req-acquired by done() */
while (!list_empty(&ep->queue)) {
req = list_first_entry(&ep->queue, struct ast_vhub_req, queue);
ast_vhub_done(ep, req, status);
count++;
}
if (count)
EPDBG(ep, "Nuked %d request(s)\n", count);
}
struct usb_request *ast_vhub_alloc_request(struct usb_ep *u_ep,
gfp_t gfp_flags)
{
struct ast_vhub_req *req;
req = kzalloc(sizeof(*req), gfp_flags);
if (!req)
return NULL;
return &req->req;
}
void ast_vhub_free_request(struct usb_ep *u_ep, struct usb_request *u_req)
{
struct ast_vhub_req *req = to_ast_req(u_req);
kfree(req);
}
static irqreturn_t ast_vhub_irq(int irq, void *data)
{
struct ast_vhub *vhub = data;
irqreturn_t iret = IRQ_NONE;
u32 i, istat;
/* Stale interrupt while tearing down */
if (!vhub->ep0_bufs)
return IRQ_NONE;
spin_lock(&vhub->lock);
/* Read and ACK interrupts */
istat = readl(vhub->regs + AST_VHUB_ISR);
if (!istat)
goto bail;
writel(istat, vhub->regs + AST_VHUB_ISR);
iret = IRQ_HANDLED;
UDCVDBG(vhub, "irq status=%08x, ep_acks=%08x ep_nacks=%08x\n",
istat,
readl(vhub->regs + AST_VHUB_EP_ACK_ISR),
readl(vhub->regs + AST_VHUB_EP_NACK_ISR));
/* Handle generic EPs first */
if (istat & VHUB_IRQ_EP_POOL_ACK_STALL) {
u32 ep_acks = readl(vhub->regs + AST_VHUB_EP_ACK_ISR);
writel(ep_acks, vhub->regs + AST_VHUB_EP_ACK_ISR);
for (i = 0; ep_acks && i < vhub->max_epns; i++) {
u32 mask = VHUB_EP_IRQ(i);
if (ep_acks & mask) {
ast_vhub_epn_ack_irq(&vhub->epns[i]);
ep_acks &= ~mask;
}
}
}
/* Handle device interrupts */
if (istat & vhub->port_irq_mask) {
for (i = 0; i < vhub->max_ports; i++) {
if (istat & VHUB_DEV_IRQ(i))
ast_vhub_dev_irq(&vhub->ports[i].dev);
}
}
/* Handle top-level vHub EP0 interrupts */
if (istat & (VHUB_IRQ_HUB_EP0_OUT_ACK_STALL |
VHUB_IRQ_HUB_EP0_IN_ACK_STALL |
VHUB_IRQ_HUB_EP0_SETUP)) {
if (istat & VHUB_IRQ_HUB_EP0_IN_ACK_STALL)
ast_vhub_ep0_handle_ack(&vhub->ep0, true);
if (istat & VHUB_IRQ_HUB_EP0_OUT_ACK_STALL)
ast_vhub_ep0_handle_ack(&vhub->ep0, false);
if (istat & VHUB_IRQ_HUB_EP0_SETUP)
ast_vhub_ep0_handle_setup(&vhub->ep0);
}
/* Various top level bus events */
if (istat & (VHUB_IRQ_BUS_RESUME |
VHUB_IRQ_BUS_SUSPEND |
VHUB_IRQ_BUS_RESET)) {
if (istat & VHUB_IRQ_BUS_RESUME)
ast_vhub_hub_resume(vhub);
if (istat & VHUB_IRQ_BUS_SUSPEND)
ast_vhub_hub_suspend(vhub);
if (istat & VHUB_IRQ_BUS_RESET)
ast_vhub_hub_reset(vhub);
}
bail:
spin_unlock(&vhub->lock);
return iret;
}
void ast_vhub_init_hw(struct ast_vhub *vhub)
{
u32 ctrl, port_mask, epn_mask;
UDCDBG(vhub,"(Re)Starting HW ...\n");
/* Enable PHY */
ctrl = VHUB_CTRL_PHY_CLK |
VHUB_CTRL_PHY_RESET_DIS;
/*
* We do *NOT* set the VHUB_CTRL_CLK_STOP_SUSPEND bit
* to stop the logic clock during suspend because
* it causes the registers to become inaccessible and
* we haven't yet figured out a good wayt to bring the
* controller back into life to issue a wakeup.
*/
/*
* Set some ISO & split control bits according to Aspeed
* recommendation
*
* VHUB_CTRL_ISO_RSP_CTRL: When set tells the HW to respond
* with 0 bytes data packet to ISO IN endpoints when no data
* is available.
*
* VHUB_CTRL_SPLIT_IN: This makes a SOF complete a split IN
* transaction.
*/
ctrl |= VHUB_CTRL_ISO_RSP_CTRL | VHUB_CTRL_SPLIT_IN;
writel(ctrl, vhub->regs + AST_VHUB_CTRL);
udelay(1);
/* Set descriptor ring size */
if (AST_VHUB_DESCS_COUNT == 256) {
ctrl |= VHUB_CTRL_LONG_DESC;
writel(ctrl, vhub->regs + AST_VHUB_CTRL);
} else {
BUILD_BUG_ON(AST_VHUB_DESCS_COUNT != 32);
}
/* Reset all devices */
port_mask = GENMASK(vhub->max_ports, 1);
writel(VHUB_SW_RESET_ROOT_HUB |
VHUB_SW_RESET_DMA_CONTROLLER |
VHUB_SW_RESET_EP_POOL |
port_mask, vhub->regs + AST_VHUB_SW_RESET);
udelay(1);
writel(0, vhub->regs + AST_VHUB_SW_RESET);
/* Disable and cleanup EP ACK/NACK interrupts */
epn_mask = GENMASK(vhub->max_epns - 1, 0);
writel(0, vhub->regs + AST_VHUB_EP_ACK_IER);
writel(0, vhub->regs + AST_VHUB_EP_NACK_IER);
writel(epn_mask, vhub->regs + AST_VHUB_EP_ACK_ISR);
writel(epn_mask, vhub->regs + AST_VHUB_EP_NACK_ISR);
/* Default settings for EP0, enable HW hub EP1 */
writel(0, vhub->regs + AST_VHUB_EP0_CTRL);
writel(VHUB_EP1_CTRL_RESET_TOGGLE |
VHUB_EP1_CTRL_ENABLE,
vhub->regs + AST_VHUB_EP1_CTRL);
writel(0, vhub->regs + AST_VHUB_EP1_STS_CHG);
/* Configure EP0 DMA buffer */
writel(vhub->ep0.buf_dma, vhub->regs + AST_VHUB_EP0_DATA);
/* Clear address */
writel(0, vhub->regs + AST_VHUB_CONF);
/* Pullup hub (activate on host) */
if (vhub->force_usb1)
ctrl |= VHUB_CTRL_FULL_SPEED_ONLY;
ctrl |= VHUB_CTRL_UPSTREAM_CONNECT;
writel(ctrl, vhub->regs + AST_VHUB_CTRL);
/* Enable some interrupts */
writel(VHUB_IRQ_HUB_EP0_IN_ACK_STALL |
VHUB_IRQ_HUB_EP0_OUT_ACK_STALL |
VHUB_IRQ_HUB_EP0_SETUP |
VHUB_IRQ_EP_POOL_ACK_STALL |
VHUB_IRQ_BUS_RESUME |
VHUB_IRQ_BUS_SUSPEND |
VHUB_IRQ_BUS_RESET,
vhub->regs + AST_VHUB_IER);
}
static void ast_vhub_remove(struct platform_device *pdev)
{
struct ast_vhub *vhub = platform_get_drvdata(pdev);
unsigned long flags;
int i;
if (!vhub || !vhub->regs)
return;
/* Remove devices */
for (i = 0; i < vhub->max_ports; i++)
ast_vhub_del_dev(&vhub->ports[i].dev);
spin_lock_irqsave(&vhub->lock, flags);
/* Mask & ack all interrupts */
writel(0, vhub->regs + AST_VHUB_IER);
writel(VHUB_IRQ_ACK_ALL, vhub->regs + AST_VHUB_ISR);
/* Pull device, leave PHY enabled */
writel(VHUB_CTRL_PHY_CLK |
VHUB_CTRL_PHY_RESET_DIS,
vhub->regs + AST_VHUB_CTRL);
if (vhub->clk)
clk_disable_unprepare(vhub->clk);
spin_unlock_irqrestore(&vhub->lock, flags);
if (vhub->ep0_bufs)
dma_free_coherent(&pdev->dev,
AST_VHUB_EP0_MAX_PACKET *
(vhub->max_ports + 1),
vhub->ep0_bufs,
vhub->ep0_bufs_dma);
vhub->ep0_bufs = NULL;
}
static int ast_vhub_probe(struct platform_device *pdev)
{
enum usb_device_speed max_speed;
struct ast_vhub *vhub;
struct resource *res;
int i, rc = 0;
const struct device_node *np = pdev->dev.of_node;
vhub = devm_kzalloc(&pdev->dev, sizeof(*vhub), GFP_KERNEL);
if (!vhub)
return -ENOMEM;
rc = of_property_read_u32(np, "aspeed,vhub-downstream-ports",
&vhub->max_ports);
if (rc < 0)
vhub->max_ports = AST_VHUB_NUM_PORTS;
vhub->ports = devm_kcalloc(&pdev->dev, vhub->max_ports,
sizeof(*vhub->ports), GFP_KERNEL);
if (!vhub->ports)
return -ENOMEM;
rc = of_property_read_u32(np, "aspeed,vhub-generic-endpoints",
&vhub->max_epns);
if (rc < 0)
vhub->max_epns = AST_VHUB_NUM_GEN_EPs;
vhub->epns = devm_kcalloc(&pdev->dev, vhub->max_epns,
sizeof(*vhub->epns), GFP_KERNEL);
if (!vhub->epns)
return -ENOMEM;
spin_lock_init(&vhub->lock);
vhub->pdev = pdev;
vhub->port_irq_mask = GENMASK(VHUB_IRQ_DEV1_BIT + vhub->max_ports - 1,
VHUB_IRQ_DEV1_BIT);
vhub->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
if (IS_ERR(vhub->regs)) {
dev_err(&pdev->dev, "Failed to map resources\n");
return PTR_ERR(vhub->regs);
}
UDCDBG(vhub, "vHub@%pR mapped @%p\n", res, vhub->regs);
platform_set_drvdata(pdev, vhub);
vhub->clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(vhub->clk)) {
rc = PTR_ERR(vhub->clk);
goto err;
}
rc = clk_prepare_enable(vhub->clk);
if (rc) {
dev_err(&pdev->dev, "Error couldn't enable clock (%d)\n", rc);
goto err;
}
/* Check if we need to limit the HW to USB1 */
max_speed = usb_get_maximum_speed(&pdev->dev);
if (max_speed != USB_SPEED_UNKNOWN && max_speed < USB_SPEED_HIGH)
vhub->force_usb1 = true;
/* Mask & ack all interrupts before installing the handler */
writel(0, vhub->regs + AST_VHUB_IER);
writel(VHUB_IRQ_ACK_ALL, vhub->regs + AST_VHUB_ISR);
/* Find interrupt and install handler */
vhub->irq = platform_get_irq(pdev, 0);
if (vhub->irq < 0) {
rc = vhub->irq;
goto err;
}
rc = devm_request_irq(&pdev->dev, vhub->irq, ast_vhub_irq, 0,
KBUILD_MODNAME, vhub);
if (rc) {
dev_err(&pdev->dev, "Failed to request interrupt\n");
goto err;
}
/*
* Allocate DMA buffers for all EP0s in one chunk,
* one per port and one for the vHub itself
*/
vhub->ep0_bufs = dma_alloc_coherent(&pdev->dev,
AST_VHUB_EP0_MAX_PACKET *
(vhub->max_ports + 1),
&vhub->ep0_bufs_dma, GFP_KERNEL);
if (!vhub->ep0_bufs) {
dev_err(&pdev->dev, "Failed to allocate EP0 DMA buffers\n");
rc = -ENOMEM;
goto err;
}
UDCVDBG(vhub, "EP0 DMA buffers @%p (DMA 0x%08x)\n",
vhub->ep0_bufs, (u32)vhub->ep0_bufs_dma);
/* Init vHub EP0 */
ast_vhub_init_ep0(vhub, &vhub->ep0, NULL);
/* Init devices */
for (i = 0; i < vhub->max_ports && rc == 0; i++)
rc = ast_vhub_init_dev(vhub, i);
if (rc)
goto err;
/* Init hub emulation */
rc = ast_vhub_init_hub(vhub);
if (rc)
goto err;
/* Initialize HW */
ast_vhub_init_hw(vhub);
dev_info(&pdev->dev, "Initialized virtual hub in USB%d mode\n",
vhub->force_usb1 ? 1 : 2);
return 0;
err:
ast_vhub_remove(pdev);
return rc;
}
static const struct of_device_id ast_vhub_dt_ids[] = {
{
.compatible = "aspeed,ast2400-usb-vhub",
},
{
.compatible = "aspeed,ast2500-usb-vhub",
},
{
.compatible = "aspeed,ast2600-usb-vhub",
},
{ }
};
MODULE_DEVICE_TABLE(of, ast_vhub_dt_ids);
static struct platform_driver ast_vhub_driver = {
.probe = ast_vhub_probe,
.remove_new = ast_vhub_remove,
.driver = {
.name = KBUILD_MODNAME,
.of_match_table = ast_vhub_dt_ids,
},
};
module_platform_driver(ast_vhub_driver);
MODULE_DESCRIPTION("Aspeed vHub udc driver");
MODULE_AUTHOR("Benjamin Herrenschmidt <[email protected]>");
MODULE_LICENSE("GPL");
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