diff options
Diffstat (limited to 'drivers/tty/serial/8250/8250_of.c')
-rw-r--r-- | drivers/tty/serial/8250/8250_of.c | 143 |
1 files changed, 61 insertions, 82 deletions
diff --git a/drivers/tty/serial/8250/8250_of.c b/drivers/tty/serial/8250/8250_of.c index 34f17a9785e7..5d1dd992d8fb 100644 --- a/drivers/tty/serial/8250/8250_of.c +++ b/drivers/tty/serial/8250/8250_of.c @@ -4,7 +4,10 @@ * * Copyright (C) 2006 Arnd Bergmann <arnd@arndb.de>, IBM Corp. */ + +#include <linux/bits.h> #include <linux/console.h> +#include <linux/math.h> #include <linux/module.h> #include <linux/slab.h> #include <linux/serial_core.h> @@ -25,6 +28,36 @@ struct of_serial_info { int line; }; +/* Nuvoton NPCM timeout register */ +#define UART_NPCM_TOR 7 +#define UART_NPCM_TOIE BIT(7) /* Timeout Interrupt Enable */ + +static int npcm_startup(struct uart_port *port) +{ + /* + * Nuvoton calls the scratch register 'UART_TOR' (timeout + * register). Enable it, and set TIOC (timeout interrupt + * comparator) to be 0x20 for correct operation. + */ + serial_port_out(port, UART_NPCM_TOR, UART_NPCM_TOIE | 0x20); + + return serial8250_do_startup(port); +} + +/* Nuvoton NPCM UARTs have a custom divisor calculation */ +static unsigned int npcm_get_divisor(struct uart_port *port, unsigned int baud, + unsigned int *frac) +{ + return DIV_ROUND_CLOSEST(port->uartclk, 16 * baud + 2) - 2; +} + +static int npcm_setup(struct uart_port *port) +{ + port->get_divisor = npcm_get_divisor; + port->startup = npcm_startup; + return 0; +} + /* * Fill a struct uart_port for a given device node */ @@ -36,37 +69,22 @@ static int of_platform_serial_setup(struct platform_device *ofdev, struct device *dev = &ofdev->dev; struct device_node *np = dev->of_node; struct uart_port *port = &up->port; - u32 clk, spd, prop; - int ret, irq; + u32 spd; + int ret; memset(port, 0, sizeof *port); pm_runtime_enable(&ofdev->dev); pm_runtime_get_sync(&ofdev->dev); - if (of_property_read_u32(np, "clock-frequency", &clk)) { - - /* Get clk rate through clk driver if present */ - info->clk = devm_clk_get_enabled(dev, NULL); - if (IS_ERR(info->clk)) { - ret = dev_err_probe(dev, PTR_ERR(info->clk), "failed to get clock\n"); - goto err_pmruntime; - } - - clk = clk_get_rate(info->clk); - } - /* If current-speed was set, then try not to change it. */ - if (of_property_read_u32(np, "current-speed", &spd) == 0) - port->custom_divisor = clk / (16 * spd); - ret = of_address_to_resource(np, 0, &resource); if (ret) { dev_err_probe(dev, ret, "invalid address\n"); goto err_pmruntime; } - port->flags = UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF | UPF_FIXED_PORT | - UPF_FIXED_TYPE; + port->dev = &ofdev->dev; + port->flags = UPF_BOOT_AUTOCONF | UPF_FIXED_PORT | UPF_FIXED_TYPE; spin_lock_init(&port->lock); if (resource_type(&resource) == IORESOURCE_IO) { @@ -75,70 +93,31 @@ static int of_platform_serial_setup(struct platform_device *ofdev, } else { port->mapbase = resource.start; port->mapsize = resource_size(&resource); + port->flags |= UPF_IOREMAP; + } - /* Check for shifted address mapping */ - if (of_property_read_u32(np, "reg-offset", &prop) == 0) { - if (prop >= port->mapsize) { - ret = dev_err_probe(dev, -EINVAL, "reg-offset %u exceeds region size %pa\n", - prop, &port->mapsize); - goto err_pmruntime; - } + ret = uart_read_and_validate_port_properties(port); + if (ret) + goto err_pmruntime; - port->mapbase += prop; - port->mapsize -= prop; + /* Get clk rate through clk driver if present */ + if (!port->uartclk) { + info->clk = devm_clk_get_enabled(dev, NULL); + if (IS_ERR(info->clk)) { + ret = dev_err_probe(dev, PTR_ERR(info->clk), "failed to get clock\n"); + goto err_pmruntime; } - port->iotype = UPIO_MEM; - if (of_property_read_u32(np, "reg-io-width", &prop) == 0) { - switch (prop) { - case 1: - port->iotype = UPIO_MEM; - break; - case 2: - port->iotype = UPIO_MEM16; - break; - case 4: - port->iotype = of_device_is_big_endian(np) ? - UPIO_MEM32BE : UPIO_MEM32; - break; - default: - ret = dev_err_probe(dev, -EINVAL, "unsupported reg-io-width (%u)\n", - prop); - goto err_pmruntime; - } - } - port->flags |= UPF_IOREMAP; + port->uartclk = clk_get_rate(info->clk); } + /* If current-speed was set, then try not to change it. */ + if (of_property_read_u32(np, "current-speed", &spd) == 0) + port->custom_divisor = port->uartclk / (16 * spd); /* Compatibility with the deprecated pxa driver and 8250_pxa drivers. */ if (of_device_is_compatible(np, "mrvl,mmp-uart")) port->regshift = 2; - /* Check for registers offset within the devices address range */ - if (of_property_read_u32(np, "reg-shift", &prop) == 0) - port->regshift = prop; - - /* Check for fifo size */ - if (of_property_read_u32(np, "fifo-size", &prop) == 0) - port->fifosize = prop; - - /* Check for a fixed line number */ - ret = of_alias_get_id(np, "serial"); - if (ret >= 0) - port->line = ret; - - irq = of_irq_get(np, 0); - if (irq < 0) { - if (irq == -EPROBE_DEFER) { - ret = -EPROBE_DEFER; - goto err_pmruntime; - } - /* IRQ support not mandatory */ - irq = 0; - } - - port->irq = irq; - info->rst = devm_reset_control_get_optional_shared(&ofdev->dev, NULL); if (IS_ERR(info->rst)) { ret = PTR_ERR(info->rst); @@ -150,12 +129,6 @@ static int of_platform_serial_setup(struct platform_device *ofdev, goto err_pmruntime; port->type = type; - port->uartclk = clk; - - if (of_property_read_bool(np, "no-loopback-test")) - port->flags |= UPF_SKIP_TEST; - - port->dev = &ofdev->dev; port->rs485_config = serial8250_em485_config; port->rs485_supported = serial8250_em485_supported; up->rs485_start_tx = serial8250_em485_start_tx; @@ -164,10 +137,17 @@ static int of_platform_serial_setup(struct platform_device *ofdev, switch (type) { case PORT_RT2880: ret = rt288x_setup(port); - if (ret) - goto err_pmruntime; + break; + case PORT_NPCM: + ret = npcm_setup(port); + break; + default: + /* Nothing to do */ + ret = 0; break; } + if (ret) + goto err_pmruntime; if (IS_REACHABLE(CONFIG_SERIAL_8250_FSL) && (of_device_is_compatible(np, "fsl,ns16550") || @@ -240,7 +220,6 @@ static int of_platform_serial_probe(struct platform_device *ofdev) platform_set_drvdata(ofdev, info); return 0; err_dispose: - irq_dispose_mapping(port8250.port.irq); pm_runtime_put_sync(&ofdev->dev); pm_runtime_disable(&ofdev->dev); err_free: |