spi: qup: allow multiple DMA transactions per spi xfer (5884e17e) · Commits · 戴 / test

drivers/spi/spi-qup.c

+66 −26

Original line number	Diff line number	Diff line
		@@ -418,12 +418,35 @@ static void spi_qup_dma_terminate(struct spi_master *master,
		dmaengine_terminate_all(master->dma_rx);
		}

		static u32 spi_qup_sgl_get_nents_len(struct scatterlist *sgl, u32 max,
		u32 *nents)
		{
		struct scatterlist *sg;
		u32 total = 0;

		*nents = 0;

		for (sg = sgl; sg; sg = sg_next(sg)) {
		unsigned int len = sg_dma_len(sg);

		/* check for overflow as well as limit */
		if (((total + len) < total) \|\| ((total + len) > max))
		break;

		total += len;
		(*nents)++;
		}

		return total;
		}

		static int spi_qup_do_dma(struct spi_device spi, struct spi_transfer xfer,
		unsigned long timeout)
		{
		dma_async_tx_callback rx_done = NULL, tx_done = NULL;
		struct spi_master *master = spi->master;
		struct spi_qup *qup = spi_master_get_devdata(master);
		struct scatterlist tx_sgl, rx_sgl;
		int ret;

		if (xfer->rx_buf)
		@@ -431,6 +454,21 @@ static int spi_qup_do_dma(struct spi_device spi, struct spi_transfer xfer,
		else if (xfer->tx_buf)
		tx_done = spi_qup_dma_done;

		rx_sgl = xfer->rx_sg.sgl;
		tx_sgl = xfer->tx_sg.sgl;

		do {
		u32 rx_nents, tx_nents;

		if (rx_sgl)
		qup->n_words = spi_qup_sgl_get_nents_len(rx_sgl,
		SPI_MAX_XFER, &rx_nents) / qup->w_size;
		if (tx_sgl)
		qup->n_words = spi_qup_sgl_get_nents_len(tx_sgl,
		SPI_MAX_XFER, &tx_nents) / qup->w_size;
		if (!qup->n_words)
		return -EIO;

		ret = spi_qup_io_config(spi, xfer);
		if (ret)
		return ret;
		@@ -438,25 +476,20 @@ static int spi_qup_do_dma(struct spi_device spi, struct spi_transfer xfer,
		/* before issuing the descriptors, set the QUP to run */
		ret = spi_qup_set_state(qup, QUP_STATE_RUN);
		if (ret) {
		dev_warn(qup->dev, "%s(%d): cannot set RUN state\n",
		__func__, __LINE__);
		dev_warn(qup->dev, "cannot set RUN state\n");
		return ret;
		}

		if (xfer->rx_buf) {
		ret = spi_qup_prep_sg(master, xfer->rx_sg.sgl,
		xfer->rx_sg.nents, DMA_DEV_TO_MEM,
		rx_done);
		if (rx_sgl) {
		ret = spi_qup_prep_sg(master, rx_sgl, rx_nents,
		DMA_DEV_TO_MEM, rx_done);
		if (ret)
		return ret;

		dma_async_issue_pending(master->dma_rx);
		}

		if (xfer->tx_buf) {
		ret = spi_qup_prep_sg(master, xfer->tx_sg.sgl,
		xfer->tx_sg.nents, DMA_MEM_TO_DEV,
		tx_done);
		if (tx_sgl) {
		ret = spi_qup_prep_sg(master, tx_sgl, tx_nents,
		DMA_MEM_TO_DEV, tx_done);
		if (ret)
		return ret;

		@@ -466,6 +499,13 @@ static int spi_qup_do_dma(struct spi_device spi, struct spi_transfer xfer,
		if (!wait_for_completion_timeout(&qup->done, timeout))
		return -ETIMEDOUT;

		for (; rx_sgl && rx_nents--; rx_sgl = sg_next(rx_sgl))
		;
		for (; tx_sgl && tx_nents--; tx_sgl = sg_next(tx_sgl))
		;

		} while (rx_sgl \|\| tx_sgl);

		return 0;
		}

Admin message