Commit ba172c70 authored by Geert Uytterhoeven's avatar Geert Uytterhoeven Committed by Greg Kroah-Hartman
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serial: sh-sci: Use incrementing pointers instead of stack array 



There's no need to keep all buffer and DMA pointers on the stack.

Signed-off-by: default avatarGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 47b0e94a

drivers/tty/serial/sh-sci.c

+12 −14
Original line number Diff line number Diff line
@@ -1734,18 +1734,16 @@ static void sci_request_dma(struct uart_port *port) 
	chan = dma_request_channel(mask, filter, param);

	dev_dbg(port->dev, "%s: RX: got channel %p\n", __func__, chan);

	if (chan) {

		dma_addr_t dma[2];

		void *buf[2];

		int i;

		unsigned int i;

		dma_addr_t dma;

		void *buf;



		s->chan_rx = chan;



		s->buf_len_rx = 2 * max_t(size_t, 16, port->fifosize);

		buf[0] = dma_alloc_coherent(chan->device->dev,

					    s->buf_len_rx * 2, &dma[0],

					    GFP_KERNEL);



		if (!buf[0]) {

		buf = dma_alloc_coherent(chan->device->dev, s->buf_len_rx * 2,

					 &dma, GFP_KERNEL);

		if (!buf) {

			dev_warn(port->dev,

				 "Failed to allocate Rx dma buffer, using PIO\n");

			dma_release_channel(chan);
@@ -1754,16 +1752,16 @@ static void sci_request_dma(struct uart_port *port) 
			return;

		}



		buf[1] = buf[0] + s->buf_len_rx;

		dma[1] = dma[0] + s->buf_len_rx;



		for (i = 0; i < 2; i++) {

			struct scatterlist *sg = &s->sg_rx[i];



			sg_init_table(sg, 1);

			sg_set_page(sg, virt_to_page(buf[i]), s->buf_len_rx,

				    (uintptr_t)buf[i] & ~PAGE_MASK);

			sg_dma_address(sg) = dma[i];

			sg_set_page(sg, virt_to_page(buf), s->buf_len_rx,

				    (uintptr_t)buf & ~PAGE_MASK);

			sg_dma_address(sg) = dma;



			buf += s->buf_len_rx;

			dma += s->buf_len_rx;

		}



		INIT_WORK(&s->work_rx, work_fn_rx);