diff options
Diffstat (limited to 'drivers/usb/gadget/udc/aspeed-vhub/core.c')
| -rw-r--r-- | drivers/usb/gadget/udc/aspeed-vhub/core.c | 425 |
1 files changed, 425 insertions, 0 deletions
diff --git a/drivers/usb/gadget/udc/aspeed-vhub/core.c b/drivers/usb/gadget/udc/aspeed-vhub/core.c new file mode 100644 index 000000000000..db3628be38c0 --- /dev/null +++ b/drivers/usb/gadget/udc/aspeed-vhub/core.c @@ -0,0 +1,425 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * aspeed-vhub -- Driver for Aspeed SoC "vHub" USB gadget + * + * core.c - Top level support + * + * Copyright 2017 IBM Corporation + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +#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/of_gpio.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; + + EPVDBG(ep, "completing request @%p, status %d\n", req, status); + + list_del_init(&req->queue); + + if (req->req.status == -EINPROGRESS) + req->req.status = status; + + if (req->req.dma) { + if (!WARN_ON(!ep->dev)) + usb_gadget_unmap_request(&ep->dev->gadget, + &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; + + EPDBG(ep, "Nuking\n"); + + /* 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); + } +} + +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 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 i, 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 < AST_VHUB_NUM_GEN_EPs; 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_IRQ_DEVICE1 | + VHUB_IRQ_DEVICE2 | + VHUB_IRQ_DEVICE3 | + VHUB_IRQ_DEVICE4 | + VHUB_IRQ_DEVICE5)) { + if (istat & VHUB_IRQ_DEVICE1) + ast_vhub_dev_irq(&vhub->ports[0].dev); + if (istat & VHUB_IRQ_DEVICE2) + ast_vhub_dev_irq(&vhub->ports[1].dev); + if (istat & VHUB_IRQ_DEVICE3) + ast_vhub_dev_irq(&vhub->ports[2].dev); + if (istat & VHUB_IRQ_DEVICE4) + ast_vhub_dev_irq(&vhub->ports[3].dev); + if (istat & VHUB_IRQ_DEVICE5) + ast_vhub_dev_irq(&vhub->ports[4].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; + + 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 */ + writel(VHUB_SW_RESET_ALL, vhub->regs + AST_VHUB_SW_RESET); + udelay(1); + writel(0, vhub->regs + AST_VHUB_SW_RESET); + + /* Disable and cleanup EP ACK/NACK interrupts */ + writel(0, vhub->regs + AST_VHUB_EP_ACK_IER); + writel(0, vhub->regs + AST_VHUB_EP_NACK_IER); + writel(VHUB_EP_IRQ_ALL, vhub->regs + AST_VHUB_EP_ACK_ISR); + writel(VHUB_EP_IRQ_ALL, 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 int 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 0; + + /* Remove devices */ + for (i = 0; i < AST_VHUB_NUM_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 * + (AST_VHUB_NUM_PORTS + 1), + vhub->ep0_bufs, + vhub->ep0_bufs_dma); + vhub->ep0_bufs = NULL; + + return 0; +} + +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; + + vhub = devm_kzalloc(&pdev->dev, sizeof(*vhub), GFP_KERNEL); + if (!vhub) + return -ENOMEM; + + spin_lock_init(&vhub->lock); + vhub->pdev = pdev; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + vhub->regs = devm_ioremap_resource(&pdev->dev, 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) { + dev_err(&pdev->dev, "Failed to get interrupt\n"); + 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 * + (AST_VHUB_NUM_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 < AST_VHUB_NUM_PORTS && rc == 0; i++) + rc = ast_vhub_init_dev(vhub, i); + if (rc) + goto err; + + /* Init hub emulation */ + ast_vhub_init_hub(vhub); + + /* 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", + }, + { } +}; +MODULE_DEVICE_TABLE(of, ast_vhub_dt_ids); + +static struct platform_driver ast_vhub_driver = { + .probe = ast_vhub_probe, + .remove = 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 <benh@kernel.crashing.org>"); +MODULE_LICENSE("GPL"); |