diff options
Diffstat (limited to 'drivers/tty/serial/meson_uart.c')
-rw-r--r-- | drivers/tty/serial/meson_uart.c | 153 |
1 files changed, 107 insertions, 46 deletions
diff --git a/drivers/tty/serial/meson_uart.c b/drivers/tty/serial/meson_uart.c index 60f16795d16b..42e4a4c7597f 100644 --- a/drivers/tty/serial/meson_uart.c +++ b/drivers/tty/serial/meson_uart.c @@ -286,7 +286,7 @@ static int meson_uart_startup(struct uart_port *port) writel(val, port->membase + AML_UART_MISC); ret = request_irq(port->irq, meson_uart_interrupt, 0, - meson_uart_type(port), port); + port->name, port); return ret; } @@ -298,8 +298,6 @@ static void meson_uart_change_speed(struct uart_port *port, unsigned long baud) while (!meson_uart_tx_empty(port)) cpu_relax(); - val = readl(port->membase + AML_UART_REG5); - val &= ~AML_UART_BAUD_MASK; if (port->uartclk == 24000000) { val = ((port->uartclk / 3) / baud) - 1; val |= AML_UART_BAUD_XTAL; @@ -355,7 +353,7 @@ static void meson_uart_set_termios(struct uart_port *port, if (cflags & CSTOPB) val |= AML_UART_STOP_BIN_2SB; else - val &= ~AML_UART_STOP_BIN_1SB; + val |= AML_UART_STOP_BIN_1SB; if (cflags & CRTSCTS) val &= ~AML_UART_TWO_WIRE_EN; @@ -395,51 +393,25 @@ static int meson_uart_verify_port(struct uart_port *port, return ret; } -static int meson_uart_res_size(struct uart_port *port) -{ - struct platform_device *pdev = to_platform_device(port->dev); - struct resource *res; - - res = platform_get_resource(pdev, IORESOURCE_MEM, 0); - if (!res) { - dev_err(port->dev, "cannot obtain I/O memory region"); - return -ENODEV; - } - - return resource_size(res); -} - static void meson_uart_release_port(struct uart_port *port) { - int size = meson_uart_res_size(port); - - if (port->flags & UPF_IOREMAP) { - devm_release_mem_region(port->dev, port->mapbase, size); - devm_iounmap(port->dev, port->membase); - port->membase = NULL; - } + devm_iounmap(port->dev, port->membase); + port->membase = NULL; + devm_release_mem_region(port->dev, port->mapbase, port->mapsize); } static int meson_uart_request_port(struct uart_port *port) { - int size = meson_uart_res_size(port); - - if (size < 0) - return size; - - if (!devm_request_mem_region(port->dev, port->mapbase, size, + if (!devm_request_mem_region(port->dev, port->mapbase, port->mapsize, dev_name(port->dev))) { dev_err(port->dev, "Memory region busy\n"); return -EBUSY; } - if (port->flags & UPF_IOREMAP) { - port->membase = devm_ioremap_nocache(port->dev, - port->mapbase, - size); - if (port->membase == NULL) - return -ENOMEM; - } + port->membase = devm_ioremap_nocache(port->dev, port->mapbase, + port->mapsize); + if (!port->membase) + return -ENOMEM; return 0; } @@ -470,6 +442,14 @@ static struct uart_ops meson_uart_ops = { }; #ifdef CONFIG_SERIAL_MESON_CONSOLE +static void meson_uart_enable_tx_engine(struct uart_port *port) +{ + u32 val; + + val = readl(port->membase + AML_UART_CONTROL); + val |= AML_UART_TX_EN; + writel(val, port->membase + AML_UART_CONTROL); +} static void meson_console_putchar(struct uart_port *port, int ch) { @@ -499,7 +479,6 @@ static void meson_serial_port_write(struct uart_port *port, const char *s, } val = readl(port->membase + AML_UART_CONTROL); - val |= AML_UART_TX_EN; tmp = val & ~(AML_UART_TX_INT_EN | AML_UART_RX_INT_EN); writel(tmp, port->membase + AML_UART_CONTROL); @@ -538,6 +517,8 @@ static int meson_serial_console_setup(struct console *co, char *options) if (!port || !port->membase) return -ENODEV; + meson_uart_enable_tx_engine(port); + if (options) uart_parse_options(options, &baud, &parity, &bits, &flow); @@ -576,11 +557,16 @@ meson_serial_early_console_setup(struct earlycon_device *device, const char *opt if (!device->port.membase) return -ENODEV; + meson_uart_enable_tx_engine(&device->port); 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 @@ -595,11 +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) @@ -625,15 +676,20 @@ 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); port->irq = res_irq->start; - port->flags = UPF_BOOT_AUTOCONF | UPF_IOREMAP | UPF_LOW_LATENCY; + port->flags = UPF_BOOT_AUTOCONF | UPF_LOW_LATENCY; port->dev = &pdev->dev; port->line = pdev->id; port->type = PORT_MESON; @@ -668,9 +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); |