From: Stephen Warren <[email protected]> By using dma_request_slave_channel_or_err(), the DMA slave ID can be looked up from standard DT properties, and squirrelled away during channel allocation. Hence, there's no need to use a custom DT property to store the slave ID.
Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: Greg Kroah-Hartman <[email protected]> Signed-off-by: Stephen Warren <[email protected]> --- v2: * Don't allocate DMA channels inside probe(); the DMA channel setup relies on some buffers that don't get allocated until startup(). This patch is part of a series with strong internal depdendencies. I'm looking for an ack so that I can take the entire series through the Tegra and arm-soc trees. The series will be part of a stable branch that can be merged into other subsystems if needed to avoid/resolve dependencies. Greg, you'd previously ack'd this, but I had to change the patch to fix some bugs, which was a fair textual change, so I dropped your ack. --- drivers/tty/serial/serial-tegra.c | 24 ++++++------------------ 1 file changed, 6 insertions(+), 18 deletions(-) diff --git a/drivers/tty/serial/serial-tegra.c b/drivers/tty/serial/serial-tegra.c index 4455481a3517..d5c2a287b7e7 100644 --- a/drivers/tty/serial/serial-tegra.c +++ b/drivers/tty/serial/serial-tegra.c @@ -120,7 +120,6 @@ struct tegra_uart_port { bool rx_timeout; int rx_in_progress; int symb_bit; - int dma_req_sel; struct dma_chan *rx_dma_chan; struct dma_chan *tx_dma_chan; @@ -910,15 +909,14 @@ static int tegra_uart_dma_channel_allocate(struct tegra_uart_port *tup, dma_addr_t dma_phys; int ret; struct dma_slave_config dma_sconfig; - dma_cap_mask_t mask; - dma_cap_zero(mask); - dma_cap_set(DMA_SLAVE, mask); - dma_chan = dma_request_channel(mask, NULL, NULL); - if (!dma_chan) { + dma_chan = dma_request_slave_channel_reason(tup->uport.dev, + dma_to_memory ? "rx" : "tx"); + if (IS_ERR(dma_chan)) { + ret = PTR_ERR(dma_chan); dev_err(tup->uport.dev, - "Dma channel is not available, will try later\n"); - return -EPROBE_DEFER; + "DMA channel alloc failed: %d\n", ret); + return ret; } if (dma_to_memory) { @@ -938,7 +936,6 @@ static int tegra_uart_dma_channel_allocate(struct tegra_uart_port *tup, dma_buf = tup->uport.state->xmit.buf; } - dma_sconfig.slave_id = tup->dma_req_sel; if (dma_to_memory) { dma_sconfig.src_addr = tup->uport.mapbase; dma_sconfig.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; @@ -1222,17 +1219,8 @@ static int tegra_uart_parse_dt(struct platform_device *pdev, struct tegra_uart_port *tup) { struct device_node *np = pdev->dev.of_node; - u32 of_dma[2]; int port; - if (of_property_read_u32_array(np, "nvidia,dma-request-selector", - of_dma, 2) >= 0) { - tup->dma_req_sel = of_dma[1]; - } else { - dev_err(&pdev->dev, "missing dma requestor in device tree\n"); - return -EINVAL; - } - port = of_alias_get_id(np, "serial"); if (port < 0) { dev_err(&pdev->dev, "failed to get alias id, errno %d\n", port); -- 1.8.1.5 -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
