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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/usb/gadget/udc/aspeed-vhub/ep0.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/usb/gadget/udc/aspeed-vhub/ep0.c')
-rw-r--r-- | drivers/usb/gadget/udc/aspeed-vhub/ep0.c | 522 |
1 files changed, 522 insertions, 0 deletions
diff --git a/drivers/usb/gadget/udc/aspeed-vhub/ep0.c b/drivers/usb/gadget/udc/aspeed-vhub/ep0.c new file mode 100644 index 000000000..b4cf46249 --- /dev/null +++ b/drivers/usb/gadget/udc/aspeed-vhub/ep0.c @@ -0,0 +1,522 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * aspeed-vhub -- Driver for Aspeed SoC "vHub" USB gadget + * + * ep0.c - Endpoint 0 handling + * + * 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/of_gpio.h> +#include <linux/regmap.h> +#include <linux/dma-mapping.h> + +#include "vhub.h" + +int ast_vhub_reply(struct ast_vhub_ep *ep, char *ptr, int len) +{ + struct usb_request *req = &ep->ep0.req.req; + int rc; + + if (WARN_ON(ep->d_idx != 0)) + return std_req_stall; + if (WARN_ON(!ep->ep0.dir_in)) + return std_req_stall; + if (WARN_ON(len > AST_VHUB_EP0_MAX_PACKET)) + return std_req_stall; + if (WARN_ON(req->status == -EINPROGRESS)) + return std_req_stall; + + req->buf = ptr; + req->length = len; + req->complete = NULL; + req->zero = true; + + /* + * Call internal queue directly after dropping the lock. This is + * safe to do as the reply is always the last thing done when + * processing a SETUP packet, usually as a tail call + */ + spin_unlock(&ep->vhub->lock); + if (ep->ep.ops->queue(&ep->ep, req, GFP_ATOMIC)) + rc = std_req_stall; + else + rc = std_req_data; + spin_lock(&ep->vhub->lock); + return rc; +} + +int __ast_vhub_simple_reply(struct ast_vhub_ep *ep, int len, ...) +{ + u8 *buffer = ep->buf; + unsigned int i; + va_list args; + + va_start(args, len); + + /* Copy data directly into EP buffer */ + for (i = 0; i < len; i++) + buffer[i] = va_arg(args, int); + va_end(args); + + /* req->buf NULL means data is already there */ + return ast_vhub_reply(ep, NULL, len); +} + +void ast_vhub_ep0_handle_setup(struct ast_vhub_ep *ep) +{ + struct usb_ctrlrequest crq; + enum std_req_rc std_req_rc; + int rc = -ENODEV; + + if (WARN_ON(ep->d_idx != 0)) + return; + + /* + * Grab the setup packet from the chip and byteswap + * interesting fields + */ + memcpy_fromio(&crq, ep->ep0.setup, sizeof(crq)); + + EPDBG(ep, "SETUP packet %02x/%02x/%04x/%04x/%04x [%s] st=%d\n", + crq.bRequestType, crq.bRequest, + le16_to_cpu(crq.wValue), + le16_to_cpu(crq.wIndex), + le16_to_cpu(crq.wLength), + (crq.bRequestType & USB_DIR_IN) ? "in" : "out", + ep->ep0.state); + + /* + * Check our state, cancel pending requests if needed + * + * Note: Under some circumstances, we can get a new setup + * packet while waiting for the stall ack, just accept it. + * + * In any case, a SETUP packet in wrong state should have + * reset the HW state machine, so let's just log, nuke + * requests, move on. + */ + if (ep->ep0.state != ep0_state_token && + ep->ep0.state != ep0_state_stall) { + EPDBG(ep, "wrong state\n"); + ast_vhub_nuke(ep, -EIO); + } + + /* Calculate next state for EP0 */ + ep->ep0.state = ep0_state_data; + ep->ep0.dir_in = !!(crq.bRequestType & USB_DIR_IN); + + /* If this is the vHub, we handle requests differently */ + std_req_rc = std_req_driver; + if (ep->dev == NULL) { + if ((crq.bRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD) + std_req_rc = ast_vhub_std_hub_request(ep, &crq); + else if ((crq.bRequestType & USB_TYPE_MASK) == USB_TYPE_CLASS) + std_req_rc = ast_vhub_class_hub_request(ep, &crq); + else + std_req_rc = std_req_stall; + } else if ((crq.bRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD) + std_req_rc = ast_vhub_std_dev_request(ep, &crq); + + /* Act upon result */ + switch(std_req_rc) { + case std_req_complete: + goto complete; + case std_req_stall: + goto stall; + case std_req_driver: + break; + case std_req_data: + return; + } + + /* Pass request up to the gadget driver */ + if (WARN_ON(!ep->dev)) + goto stall; + if (ep->dev->driver) { + EPDBG(ep, "forwarding to gadget...\n"); + spin_unlock(&ep->vhub->lock); + rc = ep->dev->driver->setup(&ep->dev->gadget, &crq); + spin_lock(&ep->vhub->lock); + EPDBG(ep, "driver returned %d\n", rc); + } else { + EPDBG(ep, "no gadget for request !\n"); + } + if (rc >= 0) + return; + + stall: + EPDBG(ep, "stalling\n"); + writel(VHUB_EP0_CTRL_STALL, ep->ep0.ctlstat); + ep->ep0.state = ep0_state_stall; + ep->ep0.dir_in = false; + return; + + complete: + EPVDBG(ep, "sending [in] status with no data\n"); + writel(VHUB_EP0_TX_BUFF_RDY, ep->ep0.ctlstat); + ep->ep0.state = ep0_state_status; + ep->ep0.dir_in = false; +} + + +static void ast_vhub_ep0_do_send(struct ast_vhub_ep *ep, + struct ast_vhub_req *req) +{ + unsigned int chunk; + u32 reg; + + /* If this is a 0-length request, it's the gadget trying to + * send a status on our behalf. We take it from here. + */ + if (req->req.length == 0) + req->last_desc = 1; + + /* Are we done ? Complete request, otherwise wait for next interrupt */ + if (req->last_desc >= 0) { + EPVDBG(ep, "complete send %d/%d\n", + req->req.actual, req->req.length); + ep->ep0.state = ep0_state_status; + writel(VHUB_EP0_RX_BUFF_RDY, ep->ep0.ctlstat); + ast_vhub_done(ep, req, 0); + return; + } + + /* + * Next chunk cropped to max packet size. Also check if this + * is the last packet + */ + chunk = req->req.length - req->req.actual; + if (chunk > ep->ep.maxpacket) + chunk = ep->ep.maxpacket; + else if ((chunk < ep->ep.maxpacket) || !req->req.zero) + req->last_desc = 1; + + EPVDBG(ep, "send chunk=%d last=%d, req->act=%d mp=%d\n", + chunk, req->last_desc, req->req.actual, ep->ep.maxpacket); + + /* + * Copy data if any (internal requests already have data + * in the EP buffer) + */ + if (chunk && req->req.buf) + memcpy(ep->buf, req->req.buf + req->req.actual, chunk); + + vhub_dma_workaround(ep->buf); + + /* Remember chunk size and trigger send */ + reg = VHUB_EP0_SET_TX_LEN(chunk); + writel(reg, ep->ep0.ctlstat); + writel(reg | VHUB_EP0_TX_BUFF_RDY, ep->ep0.ctlstat); + req->req.actual += chunk; +} + +static void ast_vhub_ep0_rx_prime(struct ast_vhub_ep *ep) +{ + EPVDBG(ep, "rx prime\n"); + + /* Prime endpoint for receiving data */ + writel(VHUB_EP0_RX_BUFF_RDY, ep->ep0.ctlstat); +} + +static void ast_vhub_ep0_do_receive(struct ast_vhub_ep *ep, struct ast_vhub_req *req, + unsigned int len) +{ + unsigned int remain; + int rc = 0; + + /* We are receiving... grab request */ + remain = req->req.length - req->req.actual; + + EPVDBG(ep, "receive got=%d remain=%d\n", len, remain); + + /* Are we getting more than asked ? */ + if (len > remain) { + EPDBG(ep, "receiving too much (ovf: %d) !\n", + len - remain); + len = remain; + rc = -EOVERFLOW; + } + + /* Hardware return wrong data len */ + if (len < ep->ep.maxpacket && len != remain) { + EPDBG(ep, "using expected data len instead\n"); + len = remain; + } + + if (len && req->req.buf) + memcpy(req->req.buf + req->req.actual, ep->buf, len); + req->req.actual += len; + + /* Done ? */ + if (len < ep->ep.maxpacket || len == remain) { + ep->ep0.state = ep0_state_status; + writel(VHUB_EP0_TX_BUFF_RDY, ep->ep0.ctlstat); + ast_vhub_done(ep, req, rc); + } else + ast_vhub_ep0_rx_prime(ep); +} + +void ast_vhub_ep0_handle_ack(struct ast_vhub_ep *ep, bool in_ack) +{ + struct ast_vhub_req *req; + struct ast_vhub *vhub = ep->vhub; + struct device *dev = &vhub->pdev->dev; + bool stall = false; + u32 stat; + + /* Read EP0 status */ + stat = readl(ep->ep0.ctlstat); + + /* Grab current request if any */ + req = list_first_entry_or_null(&ep->queue, struct ast_vhub_req, queue); + + EPVDBG(ep, "ACK status=%08x,state=%d is_in=%d in_ack=%d req=%p\n", + stat, ep->ep0.state, ep->ep0.dir_in, in_ack, req); + + switch(ep->ep0.state) { + case ep0_state_token: + /* There should be no request queued in that state... */ + if (req) { + dev_warn(dev, "request present while in TOKEN state\n"); + ast_vhub_nuke(ep, -EINVAL); + } + dev_warn(dev, "ack while in TOKEN state\n"); + stall = true; + break; + case ep0_state_data: + /* Check the state bits corresponding to our direction */ + if ((ep->ep0.dir_in && (stat & VHUB_EP0_TX_BUFF_RDY)) || + (!ep->ep0.dir_in && (stat & VHUB_EP0_RX_BUFF_RDY)) || + (ep->ep0.dir_in != in_ack)) { + /* In that case, ignore interrupt */ + dev_warn(dev, "irq state mismatch"); + break; + } + /* + * We are in data phase and there's no request, something is + * wrong, stall + */ + if (!req) { + dev_warn(dev, "data phase, no request\n"); + stall = true; + break; + } + + /* We have a request, handle data transfers */ + if (ep->ep0.dir_in) + ast_vhub_ep0_do_send(ep, req); + else + ast_vhub_ep0_do_receive(ep, req, VHUB_EP0_RX_LEN(stat)); + return; + case ep0_state_status: + /* Nuke stale requests */ + if (req) { + dev_warn(dev, "request present while in STATUS state\n"); + ast_vhub_nuke(ep, -EINVAL); + } + + /* + * If the status phase completes with the wrong ack, stall + * the endpoint just in case, to abort whatever the host + * was doing. + */ + if (ep->ep0.dir_in == in_ack) { + dev_warn(dev, "status direction mismatch\n"); + stall = true; + } + break; + case ep0_state_stall: + /* + * There shouldn't be any request left, but nuke just in case + * otherwise the stale request will block subsequent ones + */ + ast_vhub_nuke(ep, -EIO); + break; + } + + /* Reset to token state or stall */ + if (stall) { + writel(VHUB_EP0_CTRL_STALL, ep->ep0.ctlstat); + ep->ep0.state = ep0_state_stall; + } else + ep->ep0.state = ep0_state_token; +} + +static int ast_vhub_ep0_queue(struct usb_ep* u_ep, struct usb_request *u_req, + gfp_t gfp_flags) +{ + struct ast_vhub_req *req = to_ast_req(u_req); + struct ast_vhub_ep *ep = to_ast_ep(u_ep); + struct ast_vhub *vhub = ep->vhub; + struct device *dev = &vhub->pdev->dev; + unsigned long flags; + + /* Paranoid cheks */ + if (!u_req || (!u_req->complete && !req->internal)) { + dev_warn(dev, "Bogus EP0 request ! u_req=%p\n", u_req); + if (u_req) { + dev_warn(dev, "complete=%p internal=%d\n", + u_req->complete, req->internal); + } + return -EINVAL; + } + + /* Not endpoint 0 ? */ + if (WARN_ON(ep->d_idx != 0)) + return -EINVAL; + + /* Disabled device */ + if (ep->dev && !ep->dev->enabled) + return -ESHUTDOWN; + + /* Data, no buffer and not internal ? */ + if (u_req->length && !u_req->buf && !req->internal) { + dev_warn(dev, "Request with no buffer !\n"); + return -EINVAL; + } + + EPVDBG(ep, "enqueue req @%p\n", req); + EPVDBG(ep, " l=%d zero=%d noshort=%d is_in=%d\n", + u_req->length, u_req->zero, + u_req->short_not_ok, ep->ep0.dir_in); + + /* Initialize request progress fields */ + u_req->status = -EINPROGRESS; + u_req->actual = 0; + req->last_desc = -1; + req->active = false; + + spin_lock_irqsave(&vhub->lock, flags); + + /* EP0 can only support a single request at a time */ + if (!list_empty(&ep->queue) || + ep->ep0.state == ep0_state_token || + ep->ep0.state == ep0_state_stall) { + dev_warn(dev, "EP0: Request in wrong state\n"); + EPVDBG(ep, "EP0: list_empty=%d state=%d\n", + list_empty(&ep->queue), ep->ep0.state); + spin_unlock_irqrestore(&vhub->lock, flags); + return -EBUSY; + } + + /* Add request to list and kick processing if empty */ + list_add_tail(&req->queue, &ep->queue); + + if (ep->ep0.dir_in) { + /* IN request, send data */ + ast_vhub_ep0_do_send(ep, req); + } else if (u_req->length == 0) { + /* 0-len request, send completion as rx */ + EPVDBG(ep, "0-length rx completion\n"); + ep->ep0.state = ep0_state_status; + writel(VHUB_EP0_TX_BUFF_RDY, ep->ep0.ctlstat); + ast_vhub_done(ep, req, 0); + } else { + /* OUT request, start receiver */ + ast_vhub_ep0_rx_prime(ep); + } + + spin_unlock_irqrestore(&vhub->lock, flags); + + return 0; +} + +static int ast_vhub_ep0_dequeue(struct usb_ep* u_ep, struct usb_request *u_req) +{ + struct ast_vhub_ep *ep = to_ast_ep(u_ep); + struct ast_vhub *vhub = ep->vhub; + struct ast_vhub_req *req; + unsigned long flags; + int rc = -EINVAL; + + spin_lock_irqsave(&vhub->lock, flags); + + /* Only one request can be in the queue */ + req = list_first_entry_or_null(&ep->queue, struct ast_vhub_req, queue); + + /* Is it ours ? */ + if (req && u_req == &req->req) { + EPVDBG(ep, "dequeue req @%p\n", req); + + /* + * We don't have to deal with "active" as all + * DMAs go to the EP buffers, not the request. + */ + ast_vhub_done(ep, req, -ECONNRESET); + + /* We do stall the EP to clean things up in HW */ + writel(VHUB_EP0_CTRL_STALL, ep->ep0.ctlstat); + ep->ep0.state = ep0_state_status; + ep->ep0.dir_in = false; + rc = 0; + } + spin_unlock_irqrestore(&vhub->lock, flags); + return rc; +} + + +static const struct usb_ep_ops ast_vhub_ep0_ops = { + .queue = ast_vhub_ep0_queue, + .dequeue = ast_vhub_ep0_dequeue, + .alloc_request = ast_vhub_alloc_request, + .free_request = ast_vhub_free_request, +}; + +void ast_vhub_reset_ep0(struct ast_vhub_dev *dev) +{ + struct ast_vhub_ep *ep = &dev->ep0; + + ast_vhub_nuke(ep, -EIO); + ep->ep0.state = ep0_state_token; +} + + +void ast_vhub_init_ep0(struct ast_vhub *vhub, struct ast_vhub_ep *ep, + struct ast_vhub_dev *dev) +{ + memset(ep, 0, sizeof(*ep)); + + INIT_LIST_HEAD(&ep->ep.ep_list); + INIT_LIST_HEAD(&ep->queue); + ep->ep.ops = &ast_vhub_ep0_ops; + ep->ep.name = "ep0"; + ep->ep.caps.type_control = true; + usb_ep_set_maxpacket_limit(&ep->ep, AST_VHUB_EP0_MAX_PACKET); + ep->d_idx = 0; + ep->dev = dev; + ep->vhub = vhub; + ep->ep0.state = ep0_state_token; + INIT_LIST_HEAD(&ep->ep0.req.queue); + ep->ep0.req.internal = true; + + /* Small difference between vHub and devices */ + if (dev) { + ep->ep0.ctlstat = dev->regs + AST_VHUB_DEV_EP0_CTRL; + ep->ep0.setup = vhub->regs + + AST_VHUB_SETUP0 + 8 * (dev->index + 1); + ep->buf = vhub->ep0_bufs + + AST_VHUB_EP0_MAX_PACKET * (dev->index + 1); + ep->buf_dma = vhub->ep0_bufs_dma + + AST_VHUB_EP0_MAX_PACKET * (dev->index + 1); + } else { + ep->ep0.ctlstat = vhub->regs + AST_VHUB_EP0_CTRL; + ep->ep0.setup = vhub->regs + AST_VHUB_SETUP0; + ep->buf = vhub->ep0_bufs; + ep->buf_dma = vhub->ep0_bufs_dma; + } +} |