Merge "mhi: dev: uci: Avoid resubmission of same buffer to MHI" (b6410c3f) · Commits · e / devices / android_kernel_fairphone_FP4

drivers/bus/mhi/devices/mhi_uci.c

+11 −4

Original line number	Diff line number	Diff line
		@@ -408,21 +408,29 @@ static ssize_t mhi_uci_read(struct file *file,
		}

		uci_buf = uci_chan->cur_buf;
		spin_unlock_bh(&uci_chan->lock);

		/* Copy the buffer to user space */
		to_copy = min_t(size_t, count, uci_chan->rx_size);
		ptr = uci_buf->data + (uci_buf->len - uci_chan->rx_size);
		spin_unlock_bh(&uci_chan->lock);

		ret = copy_to_user(buf, ptr, to_copy);
		if (ret)
		return ret;

		spin_lock_bh(&uci_chan->lock);
		/* Buffer already queued from diff thread while we dropped lock ? */
		if (to_copy && !uci_chan->rx_size) {
		MSG_VERB("Bailout as buffer already queued (%lu %lu)\n",
		to_copy, uci_chan->rx_size);
		goto read_error;
		}

		MSG_VERB("Copied %lu of %lu bytes\n", to_copy, uci_chan->rx_size);
		uci_chan->rx_size -= to_copy;

		/* we finished with this buffer, queue it back to hardware */
		if (!uci_chan->rx_size) {
		spin_lock_bh(&uci_chan->lock);
		uci_chan->cur_buf = NULL;

		if (uci_dev->enabled)
		@@ -437,9 +445,8 @@ static ssize_t mhi_uci_read(struct file *file,
		kfree(uci_buf->data);
		goto read_error;
		}

		spin_unlock_bh(&uci_chan->lock);
		}
		spin_unlock_bh(&uci_chan->lock);

		MSG_VERB("Returning %lu bytes\n", to_copy);