diff options
Diffstat (limited to 'drivers/tty/serial/8250/8250_mtk.c')
| -rw-r--r-- | drivers/tty/serial/8250/8250_mtk.c | 119 |
1 files changed, 75 insertions, 44 deletions
diff --git a/drivers/tty/serial/8250/8250_mtk.c b/drivers/tty/serial/8250/8250_mtk.c index 7a11fac775c4..78883ca64ddd 100644 --- a/drivers/tty/serial/8250/8250_mtk.c +++ b/drivers/tty/serial/8250/8250_mtk.c @@ -34,6 +34,7 @@ struct mtk8250_data { int line; struct clk *uart_clk; + struct clk *bus_clk; }; static void @@ -115,6 +116,36 @@ mtk8250_set_termios(struct uart_port *port, struct ktermios *termios, tty_termios_encode_baud_rate(termios, baud, baud); } +static int mtk8250_runtime_suspend(struct device *dev) +{ + struct mtk8250_data *data = dev_get_drvdata(dev); + + clk_disable_unprepare(data->uart_clk); + clk_disable_unprepare(data->bus_clk); + + return 0; +} + +static int mtk8250_runtime_resume(struct device *dev) +{ + struct mtk8250_data *data = dev_get_drvdata(dev); + int err; + + err = clk_prepare_enable(data->uart_clk); + if (err) { + dev_warn(dev, "Can't enable clock\n"); + return err; + } + + err = clk_prepare_enable(data->bus_clk); + if (err) { + dev_warn(dev, "Can't enable bus clock\n"); + return err; + } + + return 0; +} + static void mtk8250_do_pm(struct uart_port *port, unsigned int state, unsigned int old) { @@ -130,22 +161,24 @@ mtk8250_do_pm(struct uart_port *port, unsigned int state, unsigned int old) static int mtk8250_probe_of(struct platform_device *pdev, struct uart_port *p, struct mtk8250_data *data) { - int err; - struct device_node *np = pdev->dev.of_node; - - data->uart_clk = of_clk_get(np, 0); + data->uart_clk = devm_clk_get(&pdev->dev, "baud"); if (IS_ERR(data->uart_clk)) { - dev_warn(&pdev->dev, "Can't get timer clock\n"); - return PTR_ERR(data->uart_clk); + /* + * For compatibility with older device trees try unnamed + * clk when no baud clk can be found. + */ + data->uart_clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(data->uart_clk)) { + dev_warn(&pdev->dev, "Can't get uart clock\n"); + return PTR_ERR(data->uart_clk); + } + + return 0; } - err = clk_prepare_enable(data->uart_clk); - if (err) { - dev_warn(&pdev->dev, "Can't prepare clock\n"); - clk_put(data->uart_clk); - return err; - } - p->uartclk = clk_get_rate(data->uart_clk); + data->bus_clk = devm_clk_get(&pdev->dev, "bus"); + if (IS_ERR(data->bus_clk)) + return PTR_ERR(data->bus_clk); return 0; } @@ -190,19 +223,24 @@ static int mtk8250_probe(struct platform_device *pdev) uart.port.regshift = 2; uart.port.private_data = data; uart.port.set_termios = mtk8250_set_termios; + uart.port.uartclk = clk_get_rate(data->uart_clk); /* Disable Rate Fix function */ writel(0x0, uart.port.membase + (MTK_UART_RATE_FIX << uart.port.regshift)); - data->line = serial8250_register_8250_port(&uart); - if (data->line < 0) - return data->line; - platform_set_drvdata(pdev, data); - pm_runtime_set_active(&pdev->dev); pm_runtime_enable(&pdev->dev); + if (!pm_runtime_enabled(&pdev->dev)) { + err = mtk8250_runtime_resume(&pdev->dev); + if (err) + return err; + } + + data->line = serial8250_register_8250_port(&uart); + if (data->line < 0) + return data->line; return 0; } @@ -214,13 +252,13 @@ static int mtk8250_remove(struct platform_device *pdev) pm_runtime_get_sync(&pdev->dev); serial8250_unregister_port(data->line); - if (!IS_ERR(data->uart_clk)) { - clk_disable_unprepare(data->uart_clk); - clk_put(data->uart_clk); - } pm_runtime_disable(&pdev->dev); pm_runtime_put_noidle(&pdev->dev); + + if (!pm_runtime_status_suspended(&pdev->dev)) + mtk8250_runtime_suspend(&pdev->dev); + return 0; } @@ -244,28 +282,6 @@ static int mtk8250_resume(struct device *dev) } #endif /* CONFIG_PM_SLEEP */ -#ifdef CONFIG_PM -static int mtk8250_runtime_suspend(struct device *dev) -{ - struct mtk8250_data *data = dev_get_drvdata(dev); - - if (!IS_ERR(data->uart_clk)) - clk_disable_unprepare(data->uart_clk); - - return 0; -} - -static int mtk8250_runtime_resume(struct device *dev) -{ - struct mtk8250_data *data = dev_get_drvdata(dev); - - if (!IS_ERR(data->uart_clk)) - clk_prepare_enable(data->uart_clk); - - return 0; -} -#endif - static const struct dev_pm_ops mtk8250_pm_ops = { SET_SYSTEM_SLEEP_PM_OPS(mtk8250_suspend, mtk8250_resume) SET_RUNTIME_PM_OPS(mtk8250_runtime_suspend, mtk8250_runtime_resume, @@ -289,6 +305,21 @@ static struct platform_driver mtk8250_platform_driver = { }; module_platform_driver(mtk8250_platform_driver); +#ifdef CONFIG_SERIAL_8250_CONSOLE +static int __init early_mtk8250_setup(struct earlycon_device *device, + const char *options) +{ + if (!device->port.membase) + return -ENODEV; + + device->port.iotype = UPIO_MEM32; + + return early_serial8250_setup(device, NULL); +} + +OF_EARLYCON_DECLARE(mtk8250, "mediatek,mt6577-uart", early_mtk8250_setup); +#endif + MODULE_AUTHOR("Matthias Brugger"); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("Mediatek 8250 serial port driver"); |