示例#1
0
static int rockchip_spi_probe(struct platform_device *pdev)
{
	int ret = 0;
	struct rockchip_spi *rs;
	struct spi_master *master;
	struct resource *mem;
	u32 rsd_nsecs;

	master = spi_alloc_master(&pdev->dev, sizeof(struct rockchip_spi));
	if (!master)
		return -ENOMEM;

	platform_set_drvdata(pdev, master);

	rs = spi_master_get_devdata(master);

	/* Get basic io resource and map it */
	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	rs->regs = devm_ioremap_resource(&pdev->dev, mem);
	if (IS_ERR(rs->regs)) {
		ret =  PTR_ERR(rs->regs);
		goto err_ioremap_resource;
	}

	rs->apb_pclk = devm_clk_get(&pdev->dev, "apb_pclk");
	if (IS_ERR(rs->apb_pclk)) {
		dev_err(&pdev->dev, "Failed to get apb_pclk\n");
		ret = PTR_ERR(rs->apb_pclk);
		goto err_ioremap_resource;
	}

	rs->spiclk = devm_clk_get(&pdev->dev, "spiclk");
	if (IS_ERR(rs->spiclk)) {
		dev_err(&pdev->dev, "Failed to get spi_pclk\n");
		ret = PTR_ERR(rs->spiclk);
		goto err_ioremap_resource;
	}

	ret = clk_prepare_enable(rs->apb_pclk);
	if (ret) {
		dev_err(&pdev->dev, "Failed to enable apb_pclk\n");
		goto err_ioremap_resource;
	}

	ret = clk_prepare_enable(rs->spiclk);
	if (ret) {
		dev_err(&pdev->dev, "Failed to enable spi_clk\n");
		goto err_spiclk_enable;
	}

	spi_enable_chip(rs, 0);

	rs->type = SSI_MOTO_SPI;
	rs->master = master;
	rs->dev = &pdev->dev;
	rs->max_freq = clk_get_rate(rs->spiclk);

	if (!of_property_read_u32(pdev->dev.of_node, "rx-sample-delay-ns",
				  &rsd_nsecs))
		rs->rsd_nsecs = rsd_nsecs;

	rs->fifo_len = get_fifo_len(rs);
	if (!rs->fifo_len) {
		dev_err(&pdev->dev, "Failed to get fifo length\n");
		ret = -EINVAL;
		goto err_get_fifo_len;
	}

	spin_lock_init(&rs->lock);

	pm_runtime_set_active(&pdev->dev);
	pm_runtime_enable(&pdev->dev);

	master->auto_runtime_pm = true;
	master->bus_num = pdev->id;
	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LOOP;
	master->num_chipselect = 2;
	master->dev.of_node = pdev->dev.of_node;
	master->bits_per_word_mask = SPI_BPW_MASK(16) | SPI_BPW_MASK(8);

	master->set_cs = rockchip_spi_set_cs;
	master->prepare_message = rockchip_spi_prepare_message;
	master->unprepare_message = rockchip_spi_unprepare_message;
	master->transfer_one = rockchip_spi_transfer_one;
	master->handle_err = rockchip_spi_handle_err;

	rs->dma_tx.ch = dma_request_slave_channel(rs->dev, "tx");
	if (IS_ERR_OR_NULL(rs->dma_tx.ch)) {
		/* Check tx to see if we need defer probing driver */
		if (PTR_ERR(rs->dma_tx.ch) == -EPROBE_DEFER) {
			ret = -EPROBE_DEFER;
			goto err_get_fifo_len;
		}
		dev_warn(rs->dev, "Failed to request TX DMA channel\n");
	}

	rs->dma_rx.ch = dma_request_slave_channel(rs->dev, "rx");
	if (!rs->dma_rx.ch) {
		if (rs->dma_tx.ch) {
			dma_release_channel(rs->dma_tx.ch);
			rs->dma_tx.ch = NULL;
		}
		dev_warn(rs->dev, "Failed to request RX DMA channel\n");
	}

	if (rs->dma_tx.ch && rs->dma_rx.ch) {
		dma_get_slave_caps(rs->dma_rx.ch, &(rs->dma_caps));
		rs->dma_tx.addr = (dma_addr_t)(mem->start + ROCKCHIP_SPI_TXDR);
		rs->dma_rx.addr = (dma_addr_t)(mem->start + ROCKCHIP_SPI_RXDR);
		rs->dma_tx.direction = DMA_MEM_TO_DEV;
		rs->dma_rx.direction = DMA_DEV_TO_MEM;

		master->can_dma = rockchip_spi_can_dma;
		master->dma_tx = rs->dma_tx.ch;
		master->dma_rx = rs->dma_rx.ch;
	}

	ret = devm_spi_register_master(&pdev->dev, master);
	if (ret) {
		dev_err(&pdev->dev, "Failed to register master\n");
		goto err_register_master;
	}

	return 0;

err_register_master:
	pm_runtime_disable(&pdev->dev);
	if (rs->dma_tx.ch)
		dma_release_channel(rs->dma_tx.ch);
	if (rs->dma_rx.ch)
		dma_release_channel(rs->dma_rx.ch);
err_get_fifo_len:
	clk_disable_unprepare(rs->spiclk);
err_spiclk_enable:
	clk_disable_unprepare(rs->apb_pclk);
err_ioremap_resource:
	spi_master_put(master);

	return ret;
}
示例#2
0
int serial8250_request_dma(struct uart_8250_port *p)
{
	struct uart_8250_dma	*dma = p->dma;
	phys_addr_t rx_dma_addr = dma->rx_dma_addr ?
				  dma->rx_dma_addr : p->port.mapbase;
	phys_addr_t tx_dma_addr = dma->tx_dma_addr ?
				  dma->tx_dma_addr : p->port.mapbase;
	dma_cap_mask_t		mask;
	struct dma_slave_caps	caps;
	int			ret;

	/* Default slave configuration parameters */
	dma->rxconf.direction		= DMA_DEV_TO_MEM;
	dma->rxconf.src_addr_width	= DMA_SLAVE_BUSWIDTH_1_BYTE;
	dma->rxconf.src_addr		= rx_dma_addr + UART_RX;

	dma->txconf.direction		= DMA_MEM_TO_DEV;
	dma->txconf.dst_addr_width	= DMA_SLAVE_BUSWIDTH_1_BYTE;
	dma->txconf.dst_addr		= tx_dma_addr + UART_TX;

	dma_cap_zero(mask);
	dma_cap_set(DMA_SLAVE, mask);

	/* Get a channel for RX */
	dma->rxchan = dma_request_slave_channel_compat(mask,
						       dma->fn, dma->rx_param,
						       p->port.dev, "rx");
	if (!dma->rxchan)
		return -ENODEV;

	/* 8250 rx dma requires dmaengine driver to support pause/terminate */
	ret = dma_get_slave_caps(dma->rxchan, &caps);
	if (ret)
		goto release_rx;
	if (!caps.cmd_pause || !caps.cmd_terminate ||
	    caps.residue_granularity == DMA_RESIDUE_GRANULARITY_DESCRIPTOR) {
		ret = -EINVAL;
		goto release_rx;
	}

	dmaengine_slave_config(dma->rxchan, &dma->rxconf);

	/* Get a channel for TX */
	dma->txchan = dma_request_slave_channel_compat(mask,
						       dma->fn, dma->tx_param,
						       p->port.dev, "tx");
	if (!dma->txchan) {
		ret = -ENODEV;
		goto release_rx;
	}

	/* 8250 tx dma requires dmaengine driver to support terminate */
	ret = dma_get_slave_caps(dma->txchan, &caps);
	if (ret)
		goto err;
	if (!caps.cmd_terminate) {
		ret = -EINVAL;
		goto err;
	}

	dmaengine_slave_config(dma->txchan, &dma->txconf);

	/* RX buffer */
	if (!dma->rx_size)
		dma->rx_size = PAGE_SIZE;

	dma->rx_buf = dma_alloc_coherent(dma->rxchan->device->dev, dma->rx_size,
					&dma->rx_addr, GFP_KERNEL);
	if (!dma->rx_buf) {
		ret = -ENOMEM;
		goto err;
	}

	/* TX buffer */
	dma->tx_addr = dma_map_single(dma->txchan->device->dev,
					p->port.state->xmit.buf,
					UART_XMIT_SIZE,
					DMA_TO_DEVICE);
	if (dma_mapping_error(dma->txchan->device->dev, dma->tx_addr)) {
		dma_free_coherent(dma->rxchan->device->dev, dma->rx_size,
				  dma->rx_buf, dma->rx_addr);
		ret = -ENOMEM;
		goto err;
	}

	dev_dbg_ratelimited(p->port.dev, "got both dma channels\n");

	return 0;
err:
	dma_release_channel(dma->txchan);
release_rx:
	dma_release_channel(dma->rxchan);
	return ret;
}