From 491e60d63fde0a9ff09490a070d7bc22ff82c9ce Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Tue, 7 Apr 2015 11:27:20 +0200 Subject: [PATCH] greybus: es2: sync up with recent es1 changes Fix transfer-buffer alignment of es2 as well. Signed-off-by: Johan Hovold Reviewed-by: Alex Elder Signed-off-by: Greg Kroah-Hartman --- drivers/staging/greybus/es2.c | 59 ++++++++++++++++++------------------------- 1 file changed, 25 insertions(+), 34 deletions(-) diff --git a/drivers/staging/greybus/es2.c b/drivers/staging/greybus/es2.c index 10b21df253a0..45b6815dc06b 100644 --- a/drivers/staging/greybus/es2.c +++ b/drivers/staging/greybus/es2.c @@ -16,6 +16,7 @@ #include #include #include +#include #include "greybus.h" #include "svc_msg.h" @@ -127,13 +128,8 @@ static void usb_log_disable(struct es1_ap_dev *es1); */ static void hd_buffer_constraints(struct greybus_host_device *hd) { - /* - * Only one byte is required, but this produces a result - * that's better aligned for the user. - */ - hd->buffer_headroom = sizeof(u32); /* For cport id */ - hd->buffer_size_max = ES1_GBUF_MSG_SIZE_MAX - hd->buffer_headroom; - BUILD_BUG_ON(hd->buffer_headroom > GB_BUFFER_HEADROOM_MAX); + hd->buffer_headroom = 0; + hd->buffer_size_max = ES1_GBUF_MSG_SIZE_MAX; } #define ES1_TIMEOUT 500 /* 500 ms for the SVC to do something */ @@ -219,16 +215,13 @@ static void *message_send(struct greybus_host_device *hd, u16 cport_id, { struct es1_ap_dev *es1 = hd_to_es1(hd); struct usb_device *udev = es1->usb_dev; - u8 *transfer_buffer; + void *buffer; size_t buffer_size; - int transfer_buffer_size; int retval; struct urb *urb; - buffer_size = hd->buffer_headroom + sizeof(*message->header) + - message->payload_size; - transfer_buffer = message->buffer + hd->buffer_headroom - 1; - transfer_buffer_size = buffer_size - (hd->buffer_headroom - 1); + buffer = message->buffer; + buffer_size = sizeof(*message->header) + message->payload_size; /* * The data actually transferred will include an indication @@ -239,26 +232,27 @@ static void *message_send(struct greybus_host_device *hd, u16 cport_id, pr_err("request to send inbound data buffer\n"); return ERR_PTR(-EINVAL); } - if (cport_id > U8_MAX) { - pr_err("cport_id (%hd) is out of range for ES1\n", cport_id); - return ERR_PTR(-EINVAL); - } - /* OK, the destination is fine; record it in the transfer buffer */ - *transfer_buffer = cport_id; /* Find a free urb */ urb = next_free_urb(es1, gfp_mask); if (!urb) return ERR_PTR(-ENOMEM); + /* + * We (ab)use the operation-message header pad bytes to transfer the + * cport id in order to minimise overhead. + */ + put_unaligned_le16(cport_id, message->header->pad); + usb_fill_bulk_urb(urb, udev, usb_sndbulkpipe(udev, es1->cport_out_endpoint), - transfer_buffer, transfer_buffer_size, + buffer, buffer_size, cport_out_callback, message); retval = usb_submit_urb(urb, gfp_mask); if (retval) { pr_err("error %d submitting URB\n", retval); free_urb(es1, urb); + put_unaligned_le16(0, message->header->pad); return ERR_PTR(retval); } @@ -395,10 +389,10 @@ static void cport_in_callback(struct urb *urb) { struct greybus_host_device *hd = urb->context; struct device *dev = &urb->dev->dev; + struct gb_operation_msg_hdr *header; int status = check_urb_status(urb); int retval; u16 cport_id; - u8 *data; if (status) { if ((status == -EAGAIN) || (status == -EPROTO)) @@ -407,23 +401,17 @@ static void cport_in_callback(struct urb *urb) return; } - /* The size has to be at least one, for the cport id */ - if (!urb->actual_length) { - dev_err(dev, "%s: no cport id in input buffer?\n", __func__); + if (urb->actual_length < sizeof(*header)) { + dev_err(dev, "%s: short message received\n", __func__); goto exit; } - /* - * Our CPort number is the first byte of the data stream, - * the rest of the stream is "real" data - */ - data = urb->transfer_buffer; - cport_id = data[0]; - data = &data[1]; - - /* Pass this data to the greybus core */ - greybus_data_rcvd(hd, cport_id, data, urb->actual_length - 1); + header = urb->transfer_buffer; + cport_id = get_unaligned_le16(header->pad); + put_unaligned_le16(0, header->pad); + greybus_data_rcvd(hd, cport_id, urb->transfer_buffer, + urb->actual_length); exit: /* put our urb back in the request pool */ retval = usb_submit_urb(urb, GFP_ATOMIC); @@ -439,6 +427,9 @@ static void cport_out_callback(struct urb *urb) struct es1_ap_dev *es1 = hd_to_es1(hd); int status = check_urb_status(urb); + /* Clear the pad bytes used for the cport id */ + put_unaligned_le16(0, message->header->pad); + /* * Tell the submitter that the message send (attempt) is * complete, and report the status. -- 2.11.0