[PATCH RESEND v2] serial: Add driver for LPC32xx High Speed UARTs
Roland Stigge
stigge at antcom.de
Mon Jun 11 16:04:12 EDT 2012
This patch adds a driver for the 3 High Speed UARTs of the LPC32xx SoC that
support up to 921600bps. These UARTs are different from the 4 "Standard" UARTs
of the LPC32xx.
Signed-off-by: Roland Stigge <stigge at antcom.de>
---
Applies to v3.5-rc2
Changes since v1:
* Remove reference to MAJOR/MINOR numbers, dynamically allocate now
* Removed tty_schedule_flip() for framing error case
* Added tty_flip_buffer_push() for rx
* Use tty_port_tty_get() and tty_kref_put() in case tty is NULL
* Updated commit description
* Fixed locking in interrupt handler
* Write baudrate change (set_termios) back to termios
Thanks to Alan Cox for reviewing!
Documentation/devicetree/bindings/tty/serial/nxp-lpc32xx-hsuart.txt | 14
drivers/tty/serial/Kconfig | 19
drivers/tty/serial/Makefile | 1
drivers/tty/serial/lpc32xx_hs.c | 823 ++++++++++
4 files changed, 857 insertions(+)
--- /dev/null
+++ linux-2.6/Documentation/devicetree/bindings/tty/serial/nxp-lpc32xx-hsuart.txt
@@ -0,0 +1,14 @@
+* NXP LPC32xx SoC High Speed UART
+
+Required properties:
+- compatible: Should be "nxp,lpc3220-hsuart"
+- reg: Should contain registers location and length
+- interrupts: Should contain interrupt
+
+Example:
+
+ uart1: serial at 40014000 {
+ compatible = "nxp,lpc3220-hsuart";
+ reg = <0x40014000 0x1000>;
+ interrupts = <26 0>;
+ };
--- linux-2.6.orig/drivers/tty/serial/Kconfig
+++ linux-2.6/drivers/tty/serial/Kconfig
@@ -704,6 +704,25 @@ config SERIAL_PNX8XXX_CONSOLE
If you have a MIPS-based Philips SoC such as PNX8550 or PNX8330
and you want to use serial console, say Y. Otherwise, say N.
+config SERIAL_HS_LPC32XX
+ tristate "LPC32XX high speed serial port support"
+ depends on ARCH_LPC32XX && OF
+ select SERIAL_CORE
+ help
+ Support for the LPC32XX high speed serial ports (up to 900kbps).
+ Those are UARTs completely different from the Standard UARTs on the
+ LPC32XX SoC.
+ Choose M or Y here to build this driver.
+
+config SERIAL_HS_LPC32XX_CONSOLE
+ bool "Enable LPC32XX high speed UART serial console"
+ depends on SERIAL_HS_LPC32XX
+ select SERIAL_CORE_CONSOLE
+ help
+ If you would like to be able to use one of the high speed serial
+ ports on the LPC32XX as the console, you can do so by answering
+ Y to this option.
+
config SERIAL_CORE
tristate
--- linux-2.6.orig/drivers/tty/serial/Makefile
+++ linux-2.6/drivers/tty/serial/Makefile
@@ -34,6 +34,7 @@ obj-$(CONFIG_SERIAL_MUX) += mux.o
obj-$(CONFIG_SERIAL_68328) += 68328serial.o
obj-$(CONFIG_SERIAL_MCF) += mcf.o
obj-$(CONFIG_SERIAL_PMACZILOG) += pmac_zilog.o
+obj-$(CONFIG_SERIAL_HS_LPC32XX) += lpc32xx_hs.o
obj-$(CONFIG_SERIAL_DZ) += dz.o
obj-$(CONFIG_SERIAL_ZS) += zs.o
obj-$(CONFIG_SERIAL_SH_SCI) += sh-sci.o
--- /dev/null
+++ linux-2.6/drivers/tty/serial/lpc32xx_hs.c
@@ -0,0 +1,823 @@
+/*
+ * High Speed Serial Ports on NXP LPC32xx SoC
+ *
+ * Authors: Kevin Wells <kevin.wells at nxp.com>
+ * Roland Stigge <stigge at antcom.de>
+ *
+ * Copyright (C) 2010 NXP Semiconductors
+ * Copyright (C) 2012 Roland Stigge
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/ioport.h>
+#include <linux/init.h>
+#include <linux/console.h>
+#include <linux/sysrq.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/serial_core.h>
+#include <linux/serial.h>
+#include <linux/platform_device.h>
+#include <linux/delay.h>
+#include <linux/nmi.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/gpio.h>
+#include <linux/of.h>
+#include <mach/platform.h>
+#include <mach/hardware.h>
+
+/*
+ * High Speed UART register offsets
+ */
+#define LPC32XX_HSUART_FIFO(x) ((x) + 0x00)
+#define LPC32XX_HSUART_LEVEL(x) ((x) + 0x04)
+#define LPC32XX_HSUART_IIR(x) ((x) + 0x08)
+#define LPC32XX_HSUART_CTRL(x) ((x) + 0x0C)
+#define LPC32XX_HSUART_RATE(x) ((x) + 0x10)
+
+#define LPC32XX_HSU_BREAK_DATA (1 << 10)
+#define LPC32XX_HSU_ERROR_DATA (1 << 9)
+#define LPC32XX_HSU_RX_EMPTY (1 << 8)
+
+#define LPC32XX_HSU_TX_LEV(n) (((n) >> 8) & 0xFF)
+#define LPC32XX_HSU_RX_LEV(n) ((n) & 0xFF)
+
+#define LPC32XX_HSU_TX_INT_SET (1 << 6)
+#define LPC32XX_HSU_RX_OE_INT (1 << 5)
+#define LPC32XX_HSU_BRK_INT (1 << 4)
+#define LPC32XX_HSU_FE_INT (1 << 3)
+#define LPC32XX_HSU_RX_TIMEOUT_INT (1 << 2)
+#define LPC32XX_HSU_RX_TRIG_INT (1 << 1)
+#define LPC32XX_HSU_TX_INT (1 << 0)
+
+#define LPC32XX_HSU_HRTS_INV (1 << 21)
+#define LPC32XX_HSU_HRTS_TRIG_8B (0x0 << 19)
+#define LPC32XX_HSU_HRTS_TRIG_16B (0x1 << 19)
+#define LPC32XX_HSU_HRTS_TRIG_32B (0x2 << 19)
+#define LPC32XX_HSU_HRTS_TRIG_48B (0x3 << 19)
+#define LPC32XX_HSU_HRTS_EN (1 << 18)
+#define LPC32XX_HSU_TMO_DISABLED (0x0 << 16)
+#define LPC32XX_HSU_TMO_INACT_4B (0x1 << 16)
+#define LPC32XX_HSU_TMO_INACT_8B (0x2 << 16)
+#define LPC32XX_HSU_TMO_INACT_16B (0x3 << 16)
+#define LPC32XX_HSU_HCTS_INV (1 << 15)
+#define LPC32XX_HSU_HCTS_EN (1 << 14)
+#define LPC32XX_HSU_OFFSET(n) ((n) << 9)
+#define LPC32XX_HSU_BREAK (1 << 8)
+#define LPC32XX_HSU_ERR_INT_EN (1 << 7)
+#define LPC32XX_HSU_RX_INT_EN (1 << 6)
+#define LPC32XX_HSU_TX_INT_EN (1 << 5)
+#define LPC32XX_HSU_RX_TL1B (0x0 << 2)
+#define LPC32XX_HSU_RX_TL4B (0x1 << 2)
+#define LPC32XX_HSU_RX_TL8B (0x2 << 2)
+#define LPC32XX_HSU_RX_TL16B (0x3 << 2)
+#define LPC32XX_HSU_RX_TL32B (0x4 << 2)
+#define LPC32XX_HSU_RX_TL48B (0x5 << 2)
+#define LPC32XX_HSU_TX_TLEMPTY (0x0 << 0)
+#define LPC32XX_HSU_TX_TL0B (0x0 << 0)
+#define LPC32XX_HSU_TX_TL4B (0x1 << 0)
+#define LPC32XX_HSU_TX_TL8B (0x2 << 0)
+#define LPC32XX_HSU_TX_TL16B (0x3 << 0)
+
+#define MODNAME "lpc32xx_hsuart"
+
+struct lpc32xx_hsuart_port {
+ struct uart_port port;
+};
+
+#define FIFO_READ_LIMIT 128
+#define MAX_PORTS 3
+#define LPC32XX_TTY_NAME "ttyTX"
+static struct lpc32xx_hsuart_port lpc32xx_hs_ports[MAX_PORTS];
+
+#ifdef CONFIG_SERIAL_HS_LPC32XX_CONSOLE
+static void wait_for_xmit_empty(struct uart_port *port)
+{
+ unsigned int timeout = 10000;
+
+ do {
+ if (LPC32XX_HSU_TX_LEV(readl(LPC32XX_HSUART_LEVEL(
+ port->membase))) == 0)
+ break;
+ if (--timeout == 0)
+ break;
+ udelay(1);
+ } while (1);
+}
+
+static void wait_for_xmit_ready(struct uart_port *port)
+{
+ unsigned int timeout = 10000;
+
+ while (1) {
+ if (LPC32XX_HSU_TX_LEV(readl(LPC32XX_HSUART_LEVEL(
+ port->membase))) < 32)
+ break;
+ if (--timeout == 0)
+ break;
+ udelay(1);
+ }
+}
+
+static void lpc32xx_hsuart_console_putchar(struct uart_port *port, int ch)
+{
+ wait_for_xmit_ready(port);
+ writel((u32)ch, LPC32XX_HSUART_FIFO(port->membase));
+}
+
+static void lpc32xx_hsuart_console_write(struct console *co, const char *s,
+ unsigned int count)
+{
+ struct lpc32xx_hsuart_port *up = &lpc32xx_hs_ports[co->index];
+ unsigned long flags;
+ int locked = 1;
+
+ touch_nmi_watchdog();
+ local_irq_save(flags);
+ if (up->port.sysrq)
+ locked = 0;
+ else if (oops_in_progress)
+ locked = spin_trylock(&up->port.lock);
+ else
+ spin_lock(&up->port.lock);
+
+ uart_console_write(&up->port, s, count, lpc32xx_hsuart_console_putchar);
+ wait_for_xmit_empty(&up->port);
+
+ if (locked)
+ spin_unlock(&up->port.lock);
+ local_irq_restore(flags);
+}
+
+static int __init lpc32xx_hsuart_console_setup(struct console *co,
+ char *options)
+{
+ struct uart_port *port;
+ int baud = 115200;
+ int bits = 8;
+ int parity = 'n';
+ int flow = 'n';
+
+ if (co->index >= MAX_PORTS)
+ co->index = 0;
+
+ port = &lpc32xx_hs_ports[co->index].port;
+ if (!port->membase)
+ return -ENODEV;
+
+ if (options)
+ uart_parse_options(options, &baud, &parity, &bits, &flow);
+
+ return uart_set_options(port, co, baud, parity, bits, flow);
+}
+
+static struct uart_driver lpc32xx_hsuart_reg;
+static struct console lpc32xx_hsuart_console = {
+ .name = LPC32XX_TTY_NAME,
+ .write = lpc32xx_hsuart_console_write,
+ .device = uart_console_device,
+ .setup = lpc32xx_hsuart_console_setup,
+ .flags = CON_PRINTBUFFER,
+ .index = -1,
+ .data = &lpc32xx_hsuart_reg,
+};
+
+static int __init lpc32xx_hsuart_console_init(void)
+{
+ register_console(&lpc32xx_hsuart_console);
+ return 0;
+}
+console_initcall(lpc32xx_hsuart_console_init);
+
+#define LPC32XX_HSUART_CONSOLE (&lpc32xx_hsuart_console)
+#else
+#define LPC32XX_HSUART_CONSOLE NULL
+#endif
+
+static struct uart_driver lpc32xx_hs_reg = {
+ .owner = THIS_MODULE,
+ .driver_name = MODNAME,
+ .dev_name = LPC32XX_TTY_NAME,
+ .nr = MAX_PORTS,
+ .cons = LPC32XX_HSUART_CONSOLE,
+};
+static int uarts_registered;
+
+static unsigned int __serial_get_clock_div(unsigned long uartclk,
+ unsigned long rate)
+{
+ u32 div, goodrate, hsu_rate, l_hsu_rate, comprate;
+ u32 rate_diff;
+
+ /* Find the closest divider to get the desired clock rate */
+ div = uartclk / rate;
+ goodrate = hsu_rate = (div / 14) - 1;
+ if (hsu_rate != 0)
+ hsu_rate--;
+
+ /* Tweak divider */
+ l_hsu_rate = hsu_rate + 3;
+ rate_diff = 0xFFFFFFFF;
+
+ while (hsu_rate < l_hsu_rate) {
+ comprate = uartclk / ((hsu_rate + 1) * 14);
+ if (abs(comprate - rate) < rate_diff) {
+ goodrate = hsu_rate;
+ rate_diff = abs(comprate - rate);
+ }
+
+ hsu_rate++;
+ }
+ if (hsu_rate > 0xFF)
+ hsu_rate = 0xFF;
+
+ return goodrate;
+}
+
+static void __serial_uart_flush(struct uart_port *port)
+{
+ u32 tmp;
+ int cnt = 0;
+
+ while ((readl(LPC32XX_HSUART_LEVEL(port->membase)) > 0) &&
+ (cnt++ < FIFO_READ_LIMIT))
+ tmp = readl(LPC32XX_HSUART_FIFO(port->membase));
+}
+
+static void __serial_lpc32xx_rx(struct uart_port *port)
+{
+ unsigned int tmp, flag;
+ struct tty_struct *tty = tty_port_tty_get(&port->state->port);
+
+ if (!tty) {
+ /* Discard data: no tty available */
+ while (!(readl(LPC32XX_HSUART_FIFO(port->membase)) &
+ LPC32XX_HSU_RX_EMPTY))
+ ;
+
+ return;
+ }
+
+ /* Read data from FIFO and push into terminal */
+ tmp = readl(LPC32XX_HSUART_FIFO(port->membase));
+ while (!(tmp & LPC32XX_HSU_RX_EMPTY)) {
+ flag = TTY_NORMAL;
+ port->icount.rx++;
+
+ if (tmp & LPC32XX_HSU_ERROR_DATA) {
+ /* Framing error */
+ writel(LPC32XX_HSU_FE_INT,
+ LPC32XX_HSUART_IIR(port->membase));
+ port->icount.frame++;
+ flag = TTY_FRAME;
+ tty_insert_flip_char(tty, 0, TTY_FRAME);
+ }
+
+ tty_insert_flip_char(tty, (tmp & 0xFF), flag);
+
+ tmp = readl(LPC32XX_HSUART_FIFO(port->membase));
+ }
+ tty_flip_buffer_push(tty);
+ tty_kref_put(tty);
+}
+
+static void __serial_lpc32xx_tx(struct uart_port *port)
+{
+ struct circ_buf *xmit = &port->state->xmit;
+ unsigned int tmp;
+
+ if (port->x_char) {
+ writel((u32)port->x_char, LPC32XX_HSUART_FIFO(port->membase));
+ port->icount.tx++;
+ port->x_char = 0;
+ return;
+ }
+
+ if (uart_circ_empty(xmit) || uart_tx_stopped(port))
+ goto exit_tx;
+
+ /* Transfer data */
+ while (LPC32XX_HSU_TX_LEV(readl(
+ LPC32XX_HSUART_LEVEL(port->membase))) < 64) {
+ writel((u32) xmit->buf[xmit->tail],
+ LPC32XX_HSUART_FIFO(port->membase));
+ xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+ port->icount.tx++;
+ if (uart_circ_empty(xmit))
+ break;
+ }
+
+ if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+ uart_write_wakeup(port);
+
+exit_tx:
+ if (uart_circ_empty(xmit)) {
+ tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
+ tmp &= ~LPC32XX_HSU_TX_INT_EN;
+ writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
+ }
+}
+
+static irqreturn_t serial_lpc32xx_interrupt(int irq, void *dev_id)
+{
+ struct uart_port *port = dev_id;
+ struct tty_struct *tty = tty_port_tty_get(&port->state->port);
+ u32 status;
+
+ spin_lock(&port->lock);
+
+ /* Read UART status and clear latched interrupts */
+ status = readl(LPC32XX_HSUART_IIR(port->membase));
+
+ if (status & LPC32XX_HSU_BRK_INT) {
+ /* Break received */
+ writel(LPC32XX_HSU_BRK_INT, LPC32XX_HSUART_IIR(port->membase));
+ port->icount.brk++;
+ uart_handle_break(port);
+ }
+
+ /* Framing error */
+ if (status & LPC32XX_HSU_FE_INT)
+ writel(LPC32XX_HSU_FE_INT, LPC32XX_HSUART_IIR(port->membase));
+
+ if (status & LPC32XX_HSU_RX_OE_INT) {
+ /* Receive FIFO overrun */
+ writel(LPC32XX_HSU_RX_OE_INT,
+ LPC32XX_HSUART_IIR(port->membase));
+ port->icount.overrun++;
+ if (tty) {
+ tty_insert_flip_char(tty, 0, TTY_OVERRUN);
+ tty_schedule_flip(tty);
+ }
+ }
+
+ /* Data received? */
+ if (status & (LPC32XX_HSU_RX_TIMEOUT_INT | LPC32XX_HSU_RX_TRIG_INT)) {
+ __serial_lpc32xx_rx(port);
+ if (tty)
+ tty_flip_buffer_push(tty);
+ }
+
+ /* Transmit data request? */
+ if ((status & LPC32XX_HSU_TX_INT) && (!uart_tx_stopped(port))) {
+ writel(LPC32XX_HSU_TX_INT, LPC32XX_HSUART_IIR(port->membase));
+ __serial_lpc32xx_tx(port);
+ }
+
+ spin_unlock(&port->lock);
+ tty_kref_put(tty);
+
+ return IRQ_HANDLED;
+}
+
+/* port->lock is not held. */
+static unsigned int serial_lpc32xx_tx_empty(struct uart_port *port)
+{
+ unsigned int ret = 0;
+
+ if (LPC32XX_HSU_TX_LEV(readl(LPC32XX_HSUART_LEVEL(port->membase))) == 0)
+ ret = TIOCSER_TEMT;
+
+ return ret;
+}
+
+/* port->lock held by caller. */
+static void serial_lpc32xx_set_mctrl(struct uart_port *port,
+ unsigned int mctrl)
+{
+ /* No signals are supported on HS UARTs */
+}
+
+/* port->lock is held by caller and interrupts are disabled. */
+static unsigned int serial_lpc32xx_get_mctrl(struct uart_port *port)
+{
+ /* No signals are supported on HS UARTs */
+ return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
+}
+
+/* port->lock held by caller. */
+static void serial_lpc32xx_stop_tx(struct uart_port *port)
+{
+ u32 tmp;
+
+ tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
+ tmp &= ~LPC32XX_HSU_TX_INT_EN;
+ writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
+}
+
+/* port->lock held by caller. */
+static void serial_lpc32xx_start_tx(struct uart_port *port)
+{
+ u32 tmp;
+
+ __serial_lpc32xx_tx(port);
+ tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
+ tmp |= LPC32XX_HSU_TX_INT_EN;
+ writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
+}
+
+/* port->lock held by caller. */
+static void serial_lpc32xx_stop_rx(struct uart_port *port)
+{
+ u32 tmp;
+
+ tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
+ tmp &= ~(LPC32XX_HSU_RX_INT_EN | LPC32XX_HSU_ERR_INT_EN);
+ writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
+
+ writel((LPC32XX_HSU_BRK_INT | LPC32XX_HSU_RX_OE_INT |
+ LPC32XX_HSU_FE_INT), LPC32XX_HSUART_IIR(port->membase));
+}
+
+/* port->lock held by caller. */
+static void serial_lpc32xx_enable_ms(struct uart_port *port)
+{
+ /* Modem status is not supported */
+}
+
+/* port->lock is not held. */
+static void serial_lpc32xx_break_ctl(struct uart_port *port,
+ int break_state)
+{
+ unsigned long flags;
+ u32 tmp;
+
+ spin_lock_irqsave(&port->lock, flags);
+ tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
+ if (break_state != 0)
+ tmp |= LPC32XX_HSU_BREAK;
+ else
+ tmp &= ~LPC32XX_HSU_BREAK;
+ writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
+ spin_unlock_irqrestore(&port->lock, flags);
+}
+
+/* LPC3250 Errata HSUART.1: Hang workaround via loopback mode on inactivity */
+static void lpc32xx_loopback_set(resource_size_t mapbase, int state)
+{
+ int bit;
+ u32 tmp;
+
+ switch (mapbase) {
+ case LPC32XX_HS_UART1_BASE:
+ bit = 0;
+ break;
+ case LPC32XX_HS_UART2_BASE:
+ bit = 1;
+ break;
+ case LPC32XX_HS_UART7_BASE:
+ bit = 6;
+ break;
+ default:
+ WARN(1, "lpc32xx_hs: Warning: Unknown port at %08x\n", mapbase);
+ return;
+ }
+
+ tmp = readl(LPC32XX_UARTCTL_CLOOP);
+ if (state)
+ tmp |= (1 << bit);
+ else
+ tmp &= ~(1 << bit);
+ writel(tmp, LPC32XX_UARTCTL_CLOOP);
+}
+
+/* port->lock is not held. */
+static int serial_lpc32xx_startup(struct uart_port *port)
+{
+ int retval;
+ unsigned long flags;
+ u32 tmp;
+
+ spin_lock_irqsave(&port->lock, flags);
+
+ __serial_uart_flush(port);
+
+ writel((LPC32XX_HSU_TX_INT | LPC32XX_HSU_FE_INT |
+ LPC32XX_HSU_BRK_INT | LPC32XX_HSU_RX_OE_INT),
+ LPC32XX_HSUART_IIR(port->membase));
+
+ writel(0xFF, LPC32XX_HSUART_RATE(port->membase));
+
+ /*
+ * Set receiver timeout, HSU offset of 20, no break, no interrupts,
+ * and default FIFO trigger levels
+ */
+ tmp = LPC32XX_HSU_TX_TL8B | LPC32XX_HSU_RX_TL32B |
+ LPC32XX_HSU_OFFSET(20) | LPC32XX_HSU_TMO_INACT_4B;
+ writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
+
+ lpc32xx_loopback_set(port->mapbase, 0); /* get out of loopback mode */
+
+ spin_unlock_irqrestore(&port->lock, flags);
+
+ retval = request_irq(port->irq, serial_lpc32xx_interrupt,
+ 0, MODNAME, port);
+ if (!retval)
+ writel((tmp | LPC32XX_HSU_RX_INT_EN | LPC32XX_HSU_ERR_INT_EN),
+ LPC32XX_HSUART_CTRL(port->membase));
+
+ return retval;
+}
+
+/* port->lock is not held. */
+static void serial_lpc32xx_shutdown(struct uart_port *port)
+{
+ u32 tmp;
+ unsigned long flags;
+
+ spin_lock_irqsave(&port->lock, flags);
+
+ tmp = LPC32XX_HSU_TX_TL8B | LPC32XX_HSU_RX_TL32B |
+ LPC32XX_HSU_OFFSET(20) | LPC32XX_HSU_TMO_INACT_4B;
+ writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
+
+ lpc32xx_loopback_set(port->mapbase, 1); /* go to loopback mode */
+
+ spin_unlock_irqrestore(&port->lock, flags);
+
+ free_irq(port->irq, port);
+}
+
+/* port->lock is not held. */
+static void serial_lpc32xx_set_termios(struct uart_port *port,
+ struct ktermios *termios,
+ struct ktermios *old)
+{
+ unsigned long flags;
+ unsigned int baud, quot;
+ u32 tmp;
+
+ /* Always 8-bit, no parity, 1 stop bit */
+ termios->c_cflag &= ~(CSIZE | CSTOPB | PARENB | PARODD);
+ termios->c_cflag |= CS8;
+
+ termios->c_cflag &= ~(HUPCL | CMSPAR | CLOCAL | CRTSCTS);
+
+ baud = uart_get_baud_rate(port, termios, old, 0,
+ port->uartclk / 14);
+
+ quot = __serial_get_clock_div(port->uartclk, baud);
+
+ spin_lock_irqsave(&port->lock, flags);
+
+ /* Ignore characters? */
+ tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
+ if ((termios->c_cflag & CREAD) == 0)
+ tmp &= ~(LPC32XX_HSU_RX_INT_EN | LPC32XX_HSU_ERR_INT_EN);
+ else
+ tmp |= LPC32XX_HSU_RX_INT_EN | LPC32XX_HSU_ERR_INT_EN;
+ writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
+
+ writel(quot, LPC32XX_HSUART_RATE(port->membase));
+
+ uart_update_timeout(port, termios->c_cflag, baud);
+
+ spin_unlock_irqrestore(&port->lock, flags);
+
+ /* Don't rewrite B0 */
+ if (tty_termios_baud_rate(termios))
+ tty_termios_encode_baud_rate(termios, baud, baud);
+}
+
+static const char *serial_lpc32xx_type(struct uart_port *port)
+{
+ return MODNAME;
+}
+
+static void serial_lpc32xx_release_port(struct uart_port *port)
+{
+ if ((port->iotype == UPIO_MEM32) && (port->mapbase)) {
+ if (port->flags & UPF_IOREMAP) {
+ iounmap(port->membase);
+ port->membase = NULL;
+ }
+
+ release_mem_region(port->mapbase, SZ_4K);
+ }
+}
+
+static int serial_lpc32xx_request_port(struct uart_port *port)
+{
+ int ret = -ENODEV;
+
+ if ((port->iotype == UPIO_MEM32) && (port->mapbase)) {
+ ret = 0;
+
+ if (!request_mem_region(port->mapbase, SZ_4K, MODNAME))
+ ret = -EBUSY;
+ else if (port->flags & UPF_IOREMAP) {
+ port->membase = ioremap(port->mapbase, SZ_4K);
+ if (!port->membase) {
+ release_mem_region(port->mapbase, SZ_4K);
+ ret = -ENOMEM;
+ }
+ }
+ }
+
+ return ret;
+}
+
+static void serial_lpc32xx_config_port(struct uart_port *port, int uflags)
+{
+ int ret;
+
+ ret = serial_lpc32xx_request_port(port);
+ if (ret < 0)
+ return;
+ port->type = PORT_UART00;
+ port->fifosize = 64;
+
+ __serial_uart_flush(port);
+
+ writel((LPC32XX_HSU_TX_INT | LPC32XX_HSU_FE_INT |
+ LPC32XX_HSU_BRK_INT | LPC32XX_HSU_RX_OE_INT),
+ LPC32XX_HSUART_IIR(port->membase));
+
+ writel(0xFF, LPC32XX_HSUART_RATE(port->membase));
+
+ /* Set receiver timeout, HSU offset of 20, no break, no interrupts,
+ and default FIFO trigger levels */
+ writel(LPC32XX_HSU_TX_TL8B | LPC32XX_HSU_RX_TL32B |
+ LPC32XX_HSU_OFFSET(20) | LPC32XX_HSU_TMO_INACT_4B,
+ LPC32XX_HSUART_CTRL(port->membase));
+}
+
+static int serial_lpc32xx_verify_port(struct uart_port *port,
+ struct serial_struct *ser)
+{
+ int ret = 0;
+
+ if (ser->type != PORT_UART00)
+ ret = -EINVAL;
+
+ return ret;
+}
+
+static struct uart_ops serial_lpc32xx_pops = {
+ .tx_empty = serial_lpc32xx_tx_empty,
+ .set_mctrl = serial_lpc32xx_set_mctrl,
+ .get_mctrl = serial_lpc32xx_get_mctrl,
+ .stop_tx = serial_lpc32xx_stop_tx,
+ .start_tx = serial_lpc32xx_start_tx,
+ .stop_rx = serial_lpc32xx_stop_rx,
+ .enable_ms = serial_lpc32xx_enable_ms,
+ .break_ctl = serial_lpc32xx_break_ctl,
+ .startup = serial_lpc32xx_startup,
+ .shutdown = serial_lpc32xx_shutdown,
+ .set_termios = serial_lpc32xx_set_termios,
+ .type = serial_lpc32xx_type,
+ .release_port = serial_lpc32xx_release_port,
+ .request_port = serial_lpc32xx_request_port,
+ .config_port = serial_lpc32xx_config_port,
+ .verify_port = serial_lpc32xx_verify_port,
+};
+
+/*
+ * Register a set of serial devices attached to a platform device
+ */
+static int __devinit serial_hs_lpc32xx_probe(struct platform_device *pdev)
+{
+ struct lpc32xx_hsuart_port *p = &lpc32xx_hs_ports[uarts_registered];
+ int ret = 0;
+ struct resource *res;
+
+ if (uarts_registered >= MAX_PORTS) {
+ dev_err(&pdev->dev,
+ "Error: Number of possible ports exceeded (%d)!\n",
+ uarts_registered + 1);
+ return -ENXIO;
+ }
+
+ memset(p, 0, sizeof(*p));
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ dev_err(&pdev->dev,
+ "Error getting mem resource for HS UART port %d\n",
+ uarts_registered);
+ return -ENXIO;
+ }
+ p->port.mapbase = res->start;
+ p->port.membase = NULL;
+
+ p->port.irq = platform_get_irq(pdev, 0);
+ if (p->port.irq < 0) {
+ dev_err(&pdev->dev, "Error getting irq for HS UART port %d\n",
+ uarts_registered);
+ return p->port.irq;
+ }
+
+ p->port.iotype = UPIO_MEM32;
+ p->port.uartclk = LPC32XX_MAIN_OSC_FREQ;
+ p->port.regshift = 2;
+ p->port.flags = UPF_BOOT_AUTOCONF | UPF_FIXED_PORT | UPF_IOREMAP;
+ p->port.dev = &pdev->dev;
+ p->port.ops = &serial_lpc32xx_pops;
+ p->port.line = uarts_registered++;
+ spin_lock_init(&p->port.lock);
+
+ /* send port to loopback mode by default */
+ lpc32xx_loopback_set(p->port.mapbase, 1);
+
+ ret = uart_add_one_port(&lpc32xx_hs_reg, &p->port);
+
+ platform_set_drvdata(pdev, p);
+
+ return ret;
+}
+
+/*
+ * Remove serial ports registered against a platform device.
+ */
+static int __devexit serial_hs_lpc32xx_remove(struct platform_device *pdev)
+{
+ struct lpc32xx_hsuart_port *p = platform_get_drvdata(pdev);
+
+ uart_remove_one_port(&lpc32xx_hs_reg, &p->port);
+
+ return 0;
+}
+
+
+#ifdef CONFIG_PM
+static int serial_hs_lpc32xx_suspend(struct platform_device *pdev,
+ pm_message_t state)
+{
+ struct lpc32xx_hsuart_port *p = platform_get_drvdata(pdev);
+
+ uart_suspend_port(&lpc32xx_hs_reg, &p->port);
+
+ return 0;
+}
+
+static int serial_hs_lpc32xx_resume(struct platform_device *pdev)
+{
+ struct lpc32xx_hsuart_port *p = platform_get_drvdata(pdev);
+
+ uart_resume_port(&lpc32xx_hs_reg, &p->port);
+
+ return 0;
+}
+#else
+#define serial_hs_lpc32xx_suspend NULL
+#define serial_hs_lpc32xx_resume NULL
+#endif
+
+static const struct of_device_id serial_hs_lpc32xx_dt_ids[] = {
+ { .compatible = "nxp,lpc3220-hsuart" },
+ { /* sentinel */ }
+};
+
+MODULE_DEVICE_TABLE(of, serial_hs_lpc32xx_dt_ids);
+
+static struct platform_driver serial_hs_lpc32xx_driver = {
+ .probe = serial_hs_lpc32xx_probe,
+ .remove = __devexit_p(serial_hs_lpc32xx_remove),
+ .suspend = serial_hs_lpc32xx_suspend,
+ .resume = serial_hs_lpc32xx_resume,
+ .driver = {
+ .name = MODNAME,
+ .owner = THIS_MODULE,
+ .of_match_table = serial_hs_lpc32xx_dt_ids,
+ },
+};
+
+static int __init lpc32xx_hsuart_init(void)
+{
+ int ret;
+
+ ret = uart_register_driver(&lpc32xx_hs_reg);
+ if (ret)
+ return ret;
+
+ ret = platform_driver_register(&serial_hs_lpc32xx_driver);
+ if (ret)
+ uart_unregister_driver(&lpc32xx_hs_reg);
+
+ return ret;
+}
+
+static void __exit lpc32xx_hsuart_exit(void)
+{
+ platform_driver_unregister(&serial_hs_lpc32xx_driver);
+ uart_unregister_driver(&lpc32xx_hs_reg);
+}
+
+module_init(lpc32xx_hsuart_init);
+module_exit(lpc32xx_hsuart_exit);
+
+MODULE_AUTHOR("Kevin Wells <kevin.wells at nxp.com>");
+MODULE_AUTHOR("Roland Stigge <stigge at antcom.de>");
+MODULE_DESCRIPTION("NXP LPC32XX High Speed UART driver");
+MODULE_LICENSE("GPL");
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