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.
DMA channel allocation is moved to probe() so that deferred probe works. Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: Greg Kroah-Hartman <[email protected]> Cc: [email protected] Signed-off-by: Stephen Warren <[email protected]> --- 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. --- drivers/tty/serial/serial-tegra.c | 72 ++++++++++++++++----------------------- 1 file changed, 30 insertions(+), 42 deletions(-) diff --git a/drivers/tty/serial/serial-tegra.c b/drivers/tty/serial/serial-tegra.c index 4455481a3517..e07c8bfe7459 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 +909,15 @@ 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) { - dev_err(tup->uport.dev, - "Dma channel is not available, will try later\n"); - return -EPROBE_DEFER; + dma_chan = dma_request_slave_channel_or_err(tup->uport.dev, + dma_to_memory ? "rx" : "tx"); + if (IS_ERR(dma_chan)) { + ret = PTR_ERR(dma_chan); + if (ret != -EPROBE_DEFER) + dev_err(tup->uport.dev, + "DMA channel alloc failed: %d\n", ret); + return ret; } if (dma_to_memory) { @@ -938,7 +937,6 @@ 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; @@ -1000,37 +998,20 @@ static int tegra_uart_startup(struct uart_port *u) struct tegra_uart_port *tup = to_tegra_uport(u); int ret; - ret = tegra_uart_dma_channel_allocate(tup, false); - if (ret < 0) { - dev_err(u->dev, "Tx Dma allocation failed, err = %d\n", ret); - return ret; - } - - ret = tegra_uart_dma_channel_allocate(tup, true); - if (ret < 0) { - dev_err(u->dev, "Rx Dma allocation failed, err = %d\n", ret); - goto fail_rx_dma; - } - ret = tegra_uart_hw_init(tup); if (ret < 0) { dev_err(u->dev, "Uart HW init failed, err = %d\n", ret); - goto fail_hw_init; + return ret; } ret = request_irq(u->irq, tegra_uart_isr, 0, dev_name(u->dev), tup); if (ret < 0) { dev_err(u->dev, "Failed to register ISR for IRQ %d\n", u->irq); - goto fail_hw_init; + return ret; } - return 0; -fail_hw_init: - tegra_uart_dma_channel_free(tup, true); -fail_rx_dma: - tegra_uart_dma_channel_free(tup, false); - return ret; + return 0; } static void tegra_uart_shutdown(struct uart_port *u) @@ -1042,8 +1023,6 @@ static void tegra_uart_shutdown(struct uart_port *u) tup->rx_in_progress = 0; tup->tx_in_progress = 0; - tegra_uart_dma_channel_free(tup, true); - tegra_uart_dma_channel_free(tup, false); free_irq(u->irq, tup); } @@ -1222,17 +1201,8 @@ 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); @@ -1326,14 +1296,29 @@ static int tegra_uart_probe(struct platform_device *pdev) return PTR_ERR(tup->rst); } + ret = tegra_uart_dma_channel_allocate(tup, false); + if (ret < 0) + return ret; + + ret = tegra_uart_dma_channel_allocate(tup, true); + if (ret < 0) + goto err_free_dma_tx; + u->iotype = UPIO_MEM32; u->irq = platform_get_irq(pdev, 0); u->regshift = 2; ret = uart_add_one_port(&tegra_uart_driver, u); if (ret < 0) { dev_err(&pdev->dev, "Failed to add uart port, err %d\n", ret); - return ret; + goto err_free_dma_rx; } + + return 0; + +err_free_dma_tx: + tegra_uart_dma_channel_free(tup, false); +err_free_dma_rx: + tegra_uart_dma_channel_free(tup, true); return ret; } @@ -1343,6 +1328,9 @@ static int tegra_uart_remove(struct platform_device *pdev) struct uart_port *u = &tup->uport; uart_remove_one_port(&tegra_uart_driver, u); + tegra_uart_dma_channel_free(tup, true); + tegra_uart_dma_channel_free(tup, false); + return 0; } -- 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
