From 9f60e0e7aea66e87948fcde05fc873988e881c93 Mon Sep 17 00:00:00 2001 From: Helmut Klein Date: Wed, 14 Jun 2017 10:29:15 +0200 Subject: [PATCH] tty/serial: meson_uart: update to stable bindings This patch handle the stable UART bindings but also keeps compatibility with the legacy non-stable bindings until all boards uses them. Reviewed-by: Jerome Brunet Signed-off-by: Helmut Klein Signed-off-by: Neil Armstrong Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/meson_uart.c | 90 ++++++++++++++++++++++++++++++--- 1 file changed, 84 insertions(+), 6 deletions(-) diff --git a/drivers/tty/serial/meson_uart.c b/drivers/tty/serial/meson_uart.c index c0e34dabadd8..42e4a4c7597f 100644 --- a/drivers/tty/serial/meson_uart.c +++ b/drivers/tty/serial/meson_uart.c @@ -561,8 +561,12 @@ meson_serial_early_console_setup(struct earlycon_device *device, const char *opt device->con->write = meson_serial_early_console_write; return 0; } +/* Legacy bindings, should be removed when no more used */ OF_EARLYCON_DECLARE(meson, "amlogic,meson-uart", meson_serial_early_console_setup); +/* Stable bindings */ +OF_EARLYCON_DECLARE(meson, "amlogic,meson-ao-uart", + meson_serial_early_console_setup); #define MESON_SERIAL_CONSOLE (&meson_serial_console) #else @@ -577,11 +581,76 @@ static struct uart_driver meson_uart_driver = { .cons = MESON_SERIAL_CONSOLE, }; +static inline struct clk *meson_uart_probe_clock(struct device *dev, + const char *id) +{ + struct clk *clk = NULL; + int ret; + + clk = devm_clk_get(dev, id); + if (IS_ERR(clk)) + return clk; + + ret = clk_prepare_enable(clk); + if (ret) { + dev_err(dev, "couldn't enable clk\n"); + return ERR_PTR(ret); + } + + devm_add_action_or_reset(dev, + (void(*)(void *))clk_disable_unprepare, + clk); + + return clk; +} + +/* + * This function gets clocks in the legacy non-stable DT bindings. + * This code will be remove once all the platforms switch to the + * new DT bindings. + */ +static int meson_uart_probe_clocks_legacy(struct platform_device *pdev, + struct uart_port *port) +{ + struct clk *clk = NULL; + + clk = meson_uart_probe_clock(&pdev->dev, NULL); + if (IS_ERR(clk)) + return PTR_ERR(clk); + + port->uartclk = clk_get_rate(clk); + + return 0; +} + +static int meson_uart_probe_clocks(struct platform_device *pdev, + struct uart_port *port) +{ + struct clk *clk_xtal = NULL; + struct clk *clk_pclk = NULL; + struct clk *clk_baud = NULL; + + clk_pclk = meson_uart_probe_clock(&pdev->dev, "pclk"); + if (IS_ERR(clk_pclk)) + return PTR_ERR(clk_pclk); + + clk_xtal = meson_uart_probe_clock(&pdev->dev, "xtal"); + if (IS_ERR(clk_xtal)) + return PTR_ERR(clk_xtal); + + clk_baud = meson_uart_probe_clock(&pdev->dev, "baud"); + if (IS_ERR(clk_baud)) + return PTR_ERR(clk_baud); + + port->uartclk = clk_get_rate(clk_baud); + + return 0; +} + static int meson_uart_probe(struct platform_device *pdev) { struct resource *res_mem, *res_irq; struct uart_port *port; - struct clk *clk; int ret = 0; if (pdev->dev.of_node) @@ -607,11 +676,15 @@ static int meson_uart_probe(struct platform_device *pdev) if (!port) return -ENOMEM; - clk = clk_get(&pdev->dev, NULL); - if (IS_ERR(clk)) - return PTR_ERR(clk); + /* Use legacy way until all platforms switch to new bindings */ + if (of_device_is_compatible(pdev->dev.of_node, "amlogic,meson-uart")) + ret = meson_uart_probe_clocks_legacy(pdev, port); + else + ret = meson_uart_probe_clocks(pdev, port); + + if (ret) + return ret; - port->uartclk = clk_get_rate(clk); port->iotype = UPIO_MEM; port->mapbase = res_mem->start; port->mapsize = resource_size(res_mem); @@ -651,9 +724,14 @@ static int meson_uart_remove(struct platform_device *pdev) return 0; } - static const struct of_device_id meson_uart_dt_match[] = { + /* Legacy bindings, should be removed when no more used */ { .compatible = "amlogic,meson-uart" }, + /* Stable bindings */ + { .compatible = "amlogic,meson6-uart" }, + { .compatible = "amlogic,meson8-uart" }, + { .compatible = "amlogic,meson8b-uart" }, + { .compatible = "amlogic,meson-gx-uart" }, { /* sentinel */ }, }; MODULE_DEVICE_TABLE(of, meson_uart_dt_match); -- 2.20.1