[PATCH] serial/efm32: add new driver
Uwe Kleine-König
u.kleine-koenig at pengutronix.de
Fri Dec 23 00:38:12 EST 2011
Signed-off-by: Uwe Kleine-König <u.kleine-koenig at pengutronix.de>
---
changes since (implicit) v1:
- fix checkpatch issues
- use tty_port_tty_get/tty_kref_put in efm32_usart_rx_chars
- handle parity and csize in .set_termios and
efm32_usart_console_get_options
- drop clearing HUPCL from c_cflag and everything from c_iflag in
.set_termios
These were all spotted by Alan.
.../devicetree/bindings/tty/serial/efm32-usart.txt | 14 +
drivers/tty/serial/Kconfig | 10 +
drivers/tty/serial/Makefile | 1 +
drivers/tty/serial/efm32-usart.c | 750 ++++++++++++++++++++
include/linux/serial_core.h | 2 +
5 files changed, 777 insertions(+), 0 deletions(-)
create mode 100644 Documentation/devicetree/bindings/tty/serial/efm32-usart.txt
create mode 100644 drivers/tty/serial/efm32-usart.c
diff --git a/Documentation/devicetree/bindings/tty/serial/efm32-usart.txt b/Documentation/devicetree/bindings/tty/serial/efm32-usart.txt
new file mode 100644
index 0000000..eef2721
--- /dev/null
+++ b/Documentation/devicetree/bindings/tty/serial/efm32-usart.txt
@@ -0,0 +1,14 @@
+* Energymicro efm32 UART
+
+Required properties:
+- compatible : Should be "efm32,usart"
+- reg : Address and length of the register set
+- interrupts : Should contain uart interrupt
+
+Example:
+
+uart at 0x4000c400 {
+ compatible = "efm32,usart";
+ reg = <0x4000c400 0x400>;
+ interrupts = <15>;
+};
diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
index 925a1e5..cfeb0f3 100644
--- a/drivers/tty/serial/Kconfig
+++ b/drivers/tty/serial/Kconfig
@@ -1610,4 +1610,14 @@ config SERIAL_XILINX_PS_UART_CONSOLE
help
Enable a Xilinx PS UART port to be the system console.
+config SERIAL_EFM32_USART
+ bool "EFM32 USART port."
+ depends on ARCH_EFM32
+ select SERIAL_CORE
+
+config SERIAL_EFM32_USART_CONSOLE
+ bool "EFM32 USART console support"
+ depends on SERIAL_EFM32_USART=y
+ select SERIAL_CORE_CONSOLE
+
endmenu
diff --git a/drivers/tty/serial/Makefile b/drivers/tty/serial/Makefile
index e10cf5b..d3ab42b 100644
--- a/drivers/tty/serial/Makefile
+++ b/drivers/tty/serial/Makefile
@@ -94,3 +94,4 @@ obj-$(CONFIG_SERIAL_MSM_SMD) += msm_smd_tty.o
obj-$(CONFIG_SERIAL_MXS_AUART) += mxs-auart.o
obj-$(CONFIG_SERIAL_LANTIQ) += lantiq.o
obj-$(CONFIG_SERIAL_XILINX_PS_UART) += xilinx_uartps.o
+obj-$(CONFIG_SERIAL_EFM32_USART) += efm32-usart.o
diff --git a/drivers/tty/serial/efm32-usart.c b/drivers/tty/serial/efm32-usart.c
new file mode 100644
index 0000000..a46b43c
--- /dev/null
+++ b/drivers/tty/serial/efm32-usart.c
@@ -0,0 +1,750 @@
+#include <linux/kernel.h>
+#include <linux/serial_core.h>
+#include <linux/module.h>
+#include <linux/io.h>
+#include <linux/platform_device.h>
+#include <linux/console.h>
+#include <linux/slab.h>
+#include <linux/clk.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+
+#define DRIVER_NAME "efm32-usart"
+#define DEV_NAME "ttyefm"
+
+#define USARTn_CTRL 0x00
+#define USARTn_CTRL_SYNC 0x0001
+
+#define USARTn_FRAME 0x04
+#define USARTn_FRAME_DATABITS__MASK 0x000f
+#define USARTn_FRAME_DATABITS(n) ((n) - 3)
+#define USARTn_FRAME_PARITY_NONE 0x0000
+#define USARTn_FRAME_PARITY_EVEN 0x0200
+#define USARTn_FRAME_PARITY_ODD 0x0300
+#define USARTn_FRAME_STOPBITS_HALF 0x0000
+#define USARTn_FRAME_STOPBITS_ONE 0x1000
+#define USARTn_FRAME_STOPBITS_TWO 0x3000
+
+#define USARTn_CMD 0x0c
+#define USARTn_CMD_RXEN 0x0001
+#define USARTn_CMD_RXDIS 0x0002
+#define USARTn_CMD_TXEN 0x0004
+#define USARTn_CMD_TXDIS 0x0008
+
+#define USARTn_STATUS 0x10
+#define USARTn_STATUS_TXENS 0x0002
+#define USARTn_STATUS_TXC 0x0020
+#define USARTn_STATUS_TXBL 0x0040
+#define USARTn_STATUS_RXDATAV 0x0080
+
+#define USARTn_CLKDIV 0x14
+
+#define USARTn_RXDATAX 0x18
+#define USARTn_RXDATAX_PERR 0x4000
+#define USARTn_RXDATAX_FERR 0x8000
+
+#define USARTn_TXDATA 0x34
+
+#define USARTn_IF 0x40
+#define USARTn_IF_TXBL 0x0002
+#define USARTn_IF_RXDATAV 0x0004
+
+#define USARTn_IFS 0x44
+#define USARTn_IFC 0x48
+#define USARTn_IEN 0x4c
+
+#define USARTn_ROUTE 0x54
+#define USARTn_ROUTE_RXPEN 0x0001
+#define USARTn_ROUTE_TXPEN 0x0002
+
+struct efm32_usart_port {
+ struct uart_port port;
+ unsigned int txirq;
+ struct clk *clk;
+};
+#define to_efm_port(_port) container_of(_port, struct efm32_usart_port, port)
+#define efm_debug(efm_port, format, arg...) \
+ dev_dbg(efm_port->port.dev, format, ##arg)
+
+static void efm32_usart_write32(struct efm32_usart_port *efm_port,
+ u32 value, unsigned offset)
+{
+ __raw_writel(value, efm_port->port.membase + offset);
+}
+
+static u32 efm32_usart_read32(struct efm32_usart_port *efm_port,
+ unsigned offset)
+{
+ return __raw_readl(efm_port->port.membase + offset);
+}
+
+static unsigned int efm32_usart_tx_empty(struct uart_port *port)
+{
+ struct efm32_usart_port *efm_port = to_efm_port(port);
+ u32 status = efm32_usart_read32(efm_port, USARTn_STATUS);
+
+ /* XXX: does TXBL also mean that the shifter is done? */
+ if (status & USARTn_STATUS_TXBL)
+ return TIOCSER_TEMT;
+ else
+ return 0;
+}
+
+static void efm32_usart_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+ /* sorry, neither handshaking lines nor loop functionallity */
+}
+
+static unsigned int efm32_usart_get_mctrl(struct uart_port *port)
+{
+ /* sorry, no handshaking lines available */
+ return TIOCM_CAR | TIOCM_CTS | TIOCM_DSR;
+}
+
+static void efm32_usart_stop_tx(struct uart_port *port)
+{
+ struct efm32_usart_port *efm_port = to_efm_port(port);
+ u32 ien = efm32_usart_read32(efm_port, USARTn_IEN);
+
+ efm32_usart_write32(efm_port, ien & ~USARTn_IF_TXBL, USARTn_IEN);
+}
+
+static void efm32_usart_tx_chars(struct efm32_usart_port *efm_port)
+{
+ struct uart_port *port = &efm_port->port;
+ struct circ_buf *xmit = &port->state->xmit;
+
+ while (efm32_usart_read32(efm_port, USARTn_STATUS) &
+ USARTn_STATUS_TXBL) {
+ if (port->x_char) {
+ port->icount.tx++;
+ efm32_usart_write32(efm_port, port->x_char,
+ USARTn_TXDATA);
+ port->x_char = 0;
+ continue;
+ }
+ if (!uart_circ_empty(xmit) && !uart_tx_stopped(port)) {
+ port->icount.tx++;
+ efm32_usart_write32(efm_port, xmit->buf[xmit->tail],
+ USARTn_TXDATA);
+ xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+ } else
+ break;
+ }
+
+ if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+ uart_write_wakeup(port);
+
+ if (!port->x_char && uart_circ_empty(xmit))
+ efm32_usart_stop_tx(port);
+}
+
+static void efm32_usart_start_tx(struct uart_port *port)
+{
+ struct efm32_usart_port *efm_port = to_efm_port(port);
+ u32 ien;
+
+ efm32_usart_write32(efm_port, USARTn_IF_TXBL, USARTn_IFC);
+ ien = efm32_usart_read32(efm_port, USARTn_IEN);
+ efm32_usart_write32(efm_port, ien | USARTn_IF_TXBL, USARTn_IEN);
+ efm32_usart_write32(efm_port, USARTn_CMD_TXEN, USARTn_CMD);
+
+ efm32_usart_tx_chars(efm_port);
+}
+
+static void efm32_usart_stop_rx(struct uart_port *port)
+{
+ struct efm32_usart_port *efm_port = to_efm_port(port);
+
+ efm32_usart_write32(efm_port, USARTn_CMD_RXDIS, USARTn_CMD);
+}
+
+static void efm32_usart_enable_ms(struct uart_port *port)
+{
+ /* no handshake lines, no modem status interrupts */
+}
+
+static void efm32_usart_break_ctl(struct uart_port *port, int ctl)
+{
+ /* not possible without fiddling with gpios */
+}
+
+static void efm32_usart_rx_chars(struct efm32_usart_port *efm_port)
+{
+ struct uart_port *port = &efm_port->port;
+ struct tty_struct *tty = tty_port_tty_get(&port->state->port);
+
+ spin_lock(&port->lock);
+
+ while (efm32_usart_read32(efm_port, USARTn_STATUS) &
+ USARTn_STATUS_RXDATAV) {
+ u32 rxdata = efm32_usart_read32(efm_port, USARTn_RXDATAX);
+ int flag = 0;
+
+ port->icount.rx++;
+
+ /* XXX detect BREAK and overrun */
+
+ if (rxdata & USARTn_RXDATAX_PERR) {
+ port->icount.parity++;
+ if (port->read_status_mask & USARTn_RXDATAX_PERR)
+ flag = TTY_PARITY;
+ } else if (rxdata & USARTn_RXDATAX_FERR) {
+ port->icount.frame++;
+ if (port->read_status_mask & USARTn_RXDATAX_FERR)
+ flag = TTY_FRAME;
+ }
+
+ if (rxdata & port->ignore_status_mask)
+ continue;
+
+ if (tty)
+ tty_insert_flip_char(tty, rxdata, flag);
+ }
+ spin_unlock(&port->lock);
+
+ if (tty) {
+ tty_flip_buffer_push(tty);
+ tty_kref_put(tty);
+ }
+}
+
+static irqreturn_t efm32_usart_rxirq(int irq, void *data)
+{
+ struct efm32_usart_port *efm_port = data;
+ u32 irqflag = efm32_usart_read32(efm_port, USARTn_IF);
+
+ if (irqflag & USARTn_IF_RXDATAV) {
+ efm32_usart_write32(efm_port, USARTn_IF_RXDATAV, USARTn_IFC);
+ efm32_usart_rx_chars(efm_port);
+
+ return IRQ_HANDLED;
+ } else
+ return IRQ_NONE;
+}
+
+static irqreturn_t efm32_usart_txirq(int irq, void *data)
+{
+ struct efm32_usart_port *efm_port = data;
+ u32 irqflag = efm32_usart_read32(efm_port, USARTn_IF);
+
+ if (irqflag & USARTn_IF_TXBL) {
+ efm32_usart_write32(efm_port, USARTn_IF_TXBL, USARTn_IFC);
+ efm32_usart_tx_chars(efm_port);
+ return IRQ_HANDLED;
+ } else
+ return IRQ_NONE;
+}
+
+static int efm32_usart_startup(struct uart_port *port)
+{
+ struct efm32_usart_port *efm_port = to_efm_port(port);
+ int ret;
+
+ ret = clk_enable(efm_port->clk);
+ if (ret) {
+ efm_debug(efm_port, "failed to enable clk\n");
+ goto err_clk_enable;
+ }
+ port->uartclk = clk_get_rate(efm_port->clk);
+
+ /* Enable pins at default location */
+ efm32_usart_write32(efm_port, USARTn_ROUTE_RXPEN | USARTn_ROUTE_TXPEN,
+ USARTn_ROUTE);
+
+ ret = request_irq(port->irq, efm32_usart_rxirq, 0,
+ DRIVER_NAME, efm_port);
+ if (ret) {
+ efm_debug(efm_port, "failed to register rxirq\n");
+ goto err_request_irq_rx;
+ }
+
+ /* disable all irqs */
+ efm32_usart_write32(efm_port, 0, USARTn_IEN);
+
+ ret = request_irq(efm_port->txirq, efm32_usart_txirq, 0,
+ DRIVER_NAME, efm_port);
+ if (ret) {
+ efm_debug(efm_port, "failed to register txirq\n");
+ free_irq(port->irq, efm_port);
+err_request_irq_rx:
+
+ clk_disable(efm_port->clk);
+ } else {
+ efm32_usart_write32(efm_port, USARTn_IF_RXDATAV, USARTn_IEN);
+ efm32_usart_write32(efm_port, USARTn_CMD_RXEN, USARTn_CMD);
+ }
+
+err_clk_enable:
+ return ret;
+}
+
+static void efm32_usart_shutdown(struct uart_port *port)
+{
+ struct efm32_usart_port *efm_port = to_efm_port(port);
+
+ efm32_usart_write32(efm_port, 0, USARTn_IEN);
+ free_irq(port->irq, efm_port);
+
+ clk_disable(efm_port->clk);
+}
+
+static void efm32_usart_set_termios(struct uart_port *port,
+ struct ktermios *new, struct ktermios *old)
+{
+ struct efm32_usart_port *efm_port = to_efm_port(port);
+ unsigned long flags;
+ unsigned baud;
+ u32 clkdiv;
+ u32 frame = 0;
+
+ /* no modem control lines */
+ new->c_cflag &= ~(CRTSCTS | CMSPAR);
+
+ baud = uart_get_baud_rate(port, new, old,
+ DIV_ROUND_CLOSEST(port->uartclk, 16 * 8192),
+ DIV_ROUND_CLOSEST(port->uartclk, 16));
+
+ switch (new->c_cflag & CSIZE) {
+ case CS5:
+ frame |= USARTn_FRAME_DATABITS(5);
+ break;
+ case CS6:
+ frame |= USARTn_FRAME_DATABITS(6);
+ break;
+ case CS7:
+ frame |= USARTn_FRAME_DATABITS(7);
+ break;
+ case CS8:
+ frame |= USARTn_FRAME_DATABITS(8);
+ break;
+ }
+
+ /* tx only supports a "half" stop bit */
+ new->c_cflag |= CSTOPB;
+ frame |= USARTn_FRAME_STOPBITS_ONE;
+
+ if (new->c_cflag & PARENB) {
+ if (new->c_cflag & PARODD)
+ frame |= USARTn_FRAME_PARITY_ODD;
+ else
+ frame |= USARTn_FRAME_PARITY_EVEN;
+ } else
+ frame |= USARTn_FRAME_PARITY_NONE;
+
+ /*
+ * the 6 lowest bits of CLKDIV are dc, bit 6 has value 0.25.
+ * port->uartclk <= 14e6, so 4 * port->uartclk doesn't overflow.
+ */
+ clkdiv = (DIV_ROUND_CLOSEST(4 * port->uartclk, 16 * baud) - 4) << 6;
+
+ spin_lock_irqsave(&port->lock, flags);
+
+ efm32_usart_write32(efm_port,
+ USARTn_CMD_TXDIS | USARTn_CMD_RXDIS, USARTn_CMD);
+
+ port->read_status_mask = 0;
+ port->ignore_status_mask = 0;
+
+ uart_update_timeout(port, new->c_cflag, baud);
+
+ efm32_usart_write32(efm_port, 0, USARTn_CTRL);
+ efm32_usart_write32(efm_port, frame, USARTn_FRAME);
+ efm32_usart_write32(efm_port, clkdiv, USARTn_CLKDIV);
+
+ efm32_usart_write32(efm_port, USARTn_CMD_TXEN | USARTn_CMD_RXEN,
+ USARTn_CMD);
+
+ spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static const char *efm32_usart_type(struct uart_port *port)
+{
+ return port->type == PORT_EFMUSART ? "efm32-usart" : NULL;
+}
+
+static void efm32_usart_release_port(struct uart_port *port)
+{
+ struct efm32_usart_port *efm_port = to_efm_port(port);
+
+ clk_unprepare(efm_port->clk);
+ clk_put(efm_port->clk);
+ iounmap(port->membase);
+}
+
+static int efm32_usart_request_port(struct uart_port *port)
+{
+ struct efm32_usart_port *efm_port = to_efm_port(port);
+ int ret;
+
+ port->membase = ioremap(port->mapbase, 60);
+ if (!efm_port->port.membase) {
+ ret = -ENOMEM;
+ efm_debug(efm_port, "failed to remap\n");
+ goto err_ioremap;
+ }
+
+ efm_port->clk = clk_get(port->dev, NULL);
+ if (IS_ERR(efm_port->clk)) {
+ ret = PTR_ERR(efm_port->clk);
+ efm_debug(efm_port, "failed to get clock\n");
+ goto err_clk_get;
+ }
+
+ ret = clk_prepare(efm_port->clk);
+ if (ret) {
+ clk_put(efm_port->clk);
+err_clk_get:
+
+ iounmap(port->membase);
+err_ioremap:
+ return ret;
+ }
+ return 0;
+}
+
+static void efm32_usart_config_port(struct uart_port *port, int type)
+{
+ if (type & UART_CONFIG_TYPE &&
+ !efm32_usart_request_port(port))
+ port->type = PORT_EFMUSART;
+}
+
+static int efm32_usart_verify_port(struct uart_port *port,
+ struct serial_struct *serinfo)
+{
+ int ret = 0;
+
+ if (serinfo->type != PORT_UNKNOWN && serinfo->type != PORT_EFMUSART)
+ ret = -EINVAL;
+
+ return ret;
+}
+
+static struct uart_ops efm32_usart_pops = {
+ .tx_empty = efm32_usart_tx_empty,
+ .set_mctrl = efm32_usart_set_mctrl,
+ .get_mctrl = efm32_usart_get_mctrl,
+ .stop_tx = efm32_usart_stop_tx,
+ .start_tx = efm32_usart_start_tx,
+ .stop_rx = efm32_usart_stop_rx,
+ .enable_ms = efm32_usart_enable_ms,
+ .break_ctl = efm32_usart_break_ctl,
+ .startup = efm32_usart_startup,
+ .shutdown = efm32_usart_shutdown,
+ .set_termios = efm32_usart_set_termios,
+ .type = efm32_usart_type,
+ .release_port = efm32_usart_release_port,
+ .request_port = efm32_usart_request_port,
+ .config_port = efm32_usart_config_port,
+ .verify_port = efm32_usart_verify_port,
+};
+
+static struct efm32_usart_port *efm32_usart_ports[3];
+
+#ifdef CONFIG_SERIAL_EFM32_USART_CONSOLE
+static void efm32_usart_console_putchar(struct uart_port *port, int ch)
+{
+ struct efm32_usart_port *efm_port = to_efm_port(port);
+ unsigned int timeout = 0x400;
+ u32 status;
+
+ while (1) {
+ status = efm32_usart_read32(efm_port, USARTn_STATUS);
+
+ if (status & USARTn_STATUS_TXBL)
+ break;
+ if (!timeout--)
+ return;
+ }
+ efm32_usart_write32(efm_port, ch, USARTn_TXDATA);
+}
+
+static void efm32_usart_console_write(struct console *co, const char *s,
+ unsigned int count)
+{
+ struct efm32_usart_port *efm_port = efm32_usart_ports[co->index];
+ u32 status = efm32_usart_read32(efm_port, USARTn_STATUS);
+ unsigned int timeout = 0x400;
+
+ if (!(status & USARTn_STATUS_TXENS))
+ efm32_usart_write32(efm_port, USARTn_CMD_TXEN, USARTn_CMD);
+
+ uart_console_write(&efm_port->port, s, count,
+ efm32_usart_console_putchar);
+
+ /* Wait for the transmitter to become empty */
+ while (1) {
+ u32 status = efm32_usart_read32(efm_port, USARTn_STATUS);
+ if (status & USARTn_STATUS_TXC)
+ break;
+ if (!timeout--)
+ break;
+ }
+
+ if (!(status & USARTn_STATUS_TXENS))
+ efm32_usart_write32(efm_port, USARTn_CMD_TXDIS, USARTn_CMD);
+}
+
+static void efm32_usart_console_get_options(struct efm32_usart_port *efm_port,
+ int *baud, int *parity, int *bits)
+{
+ u32 ctrl = efm32_usart_read32(efm_port, USARTn_CTRL);
+ u32 route, clkdiv, frame;
+
+ if (ctrl & USARTn_CTRL_SYNC)
+ /* not operating in async mode */
+ return;
+
+ route = efm32_usart_read32(efm_port, USARTn_ROUTE);
+ if (!(route & USARTn_ROUTE_TXPEN))
+ /* tx pin not routed */
+ return;
+
+ clkdiv = efm32_usart_read32(efm_port, USARTn_CLKDIV);
+
+ *baud = DIV_ROUND_CLOSEST(4 * efm_port->port.uartclk,
+ 16 * (4 + (clkdiv >> 6)));
+
+ frame = efm32_usart_read32(efm_port, USARTn_FRAME);
+ if (frame & USARTn_FRAME_PARITY_ODD)
+ *parity = 'o';
+ else if (frame & USARTn_FRAME_PARITY_EVEN)
+ *parity = 'e';
+ else
+ *parity = 'n';
+
+ *bits = (frame & USARTn_FRAME_DATABITS__MASK) -
+ USARTn_FRAME_DATABITS(4) + 4;
+
+ efm_debug(efm_port, "get_opts: options=%d%c%d\n",
+ *baud, *parity, *bits);
+}
+
+static int efm32_usart_console_setup(struct console *co, char *options)
+{
+ struct efm32_usart_port *efm_port;
+ int baud = 115200;
+ int bits = 8;
+ int parity = 'n';
+ int flow = 'n';
+ int ret;
+
+ if (co->index < 0 || co->index >= ARRAY_SIZE(efm32_usart_ports)) {
+ unsigned i;
+ for (i = 0; i < ARRAY_SIZE(efm32_usart_ports); ++i) {
+ if (efm32_usart_ports[i]) {
+ pr_warn("efm32-console: fall back to console index %u (from %hhi)\n",
+ i, co->index);
+ co->index = i;
+ break;
+ }
+ }
+ }
+
+ efm_port = efm32_usart_ports[co->index];
+ if (!efm_port) {
+ pr_warn("efm32-console: No port at %d\n", co->index);
+ return -ENODEV;
+ }
+
+ ret = clk_prepare(efm_port->clk);
+ if (ret) {
+ dev_warn(efm_port->port.dev,
+ "console: clk_prepare failed: %d\n", ret);
+ return ret;
+ }
+
+ efm_port->port.uartclk = clk_get_rate(efm_port->clk);
+
+ if (options)
+ uart_parse_options(options, &baud, &parity, &bits, &flow);
+ else
+ efm32_usart_console_get_options(efm_port,
+ &baud, &parity, &bits);
+
+ return uart_set_options(&efm_port->port, co, baud, parity, bits, flow);
+}
+
+static struct uart_driver efm32_usart_reg;
+
+static struct console efm32_usart_console = {
+ .name = DEV_NAME,
+ .write = efm32_usart_console_write,
+ .device = uart_console_device,
+ .setup = efm32_usart_console_setup,
+ .flags = CON_PRINTBUFFER,
+ .index = -1,
+ .data = &efm32_usart_reg,
+};
+
+#else
+#define efm32_usart_console (*(struct console *)NULL)
+#endif /* ifdef CONFIG_SERIAL_EFM32_USART_CONSOLE / else */
+
+static struct uart_driver efm32_usart_reg = {
+ .owner = THIS_MODULE,
+ .driver_name = DRIVER_NAME,
+ .dev_name = DEV_NAME,
+ .nr = ARRAY_SIZE(efm32_usart_ports),
+ .cons = &efm32_usart_console,
+};
+
+static int efm32_usart_probe_dt(struct platform_device *pdev,
+ struct efm32_usart_port *efm_port)
+{
+ struct device_node *np = pdev->dev.of_node;
+ int ret;
+
+ if (!np)
+ return 1;
+
+ ret = of_alias_get_id(np, "serial");
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to get alias id: %d\n", ret);
+ return ret;
+ } else {
+ efm_port->port.line = ret;
+ return 0;
+ }
+
+}
+
+static int __devinit efm32_usart_probe(struct platform_device *pdev)
+{
+ struct efm32_usart_port *efm_port;
+ struct resource *res;
+ int ret;
+
+ efm_port = kzalloc(sizeof(*efm_port), GFP_KERNEL);
+ if (!efm_port) {
+ dev_dbg(&pdev->dev, "failed to allocate private data\n");
+ return -ENOMEM;
+ }
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ ret = -ENODEV;
+ dev_dbg(&pdev->dev, "failed to determine base address\n");
+ goto err_get_base;
+ }
+
+ if (resource_size(res) < 60) {
+ ret = -EINVAL;
+ dev_dbg(&pdev->dev, "memory resource too small\n");
+ goto err_too_small;
+ }
+
+ ret = platform_get_irq(pdev, 0);
+ if (ret <= 0) {
+ dev_dbg(&pdev->dev, "failed to get rx irq\n");
+ goto err_get_rxirq;
+ }
+
+ efm_port->port.irq = ret;
+
+ ret = platform_get_irq(pdev, 1);
+ if (ret <= 0)
+ ret = efm_port->port.irq + 1;
+
+ efm_port->txirq = ret;
+
+ efm_port->port.dev = &pdev->dev;
+ efm_port->port.mapbase = res->start;
+ efm_port->port.type = PORT_EFMUSART;
+ efm_port->port.iotype = UPIO_MEM32;
+ efm_port->port.fifosize = 2;
+ efm_port->port.ops = &efm32_usart_pops;
+ efm_port->port.flags = UPF_BOOT_AUTOCONF;
+
+ ret = efm32_usart_probe_dt(pdev, efm_port);
+ if (ret > 0)
+ /* not created by device tree */
+ efm_port->port.line = pdev->id;
+
+ if (efm_port->port.line >= 0 &&
+ efm_port->port.line < ARRAY_SIZE(efm32_usart_ports))
+ efm32_usart_ports[efm_port->port.line] = efm_port;
+
+ ret = uart_add_one_port(&efm32_usart_reg, &efm_port->port);
+ if (ret) {
+ dev_dbg(&pdev->dev, "failed to add port: %d\n", ret);
+
+ if (pdev->id >= 0 && pdev->id < ARRAY_SIZE(efm32_usart_ports))
+ efm32_usart_ports[pdev->id] = NULL;
+err_get_rxirq:
+err_too_small:
+err_get_base:
+ kfree(efm_port);
+ } else {
+ platform_set_drvdata(pdev, efm_port);
+ dev_dbg(&pdev->dev, "\\o/\n");
+ }
+
+ return ret;
+}
+
+static int __devexit efm32_usart_remove(struct platform_device *pdev)
+{
+ struct efm32_usart_port *efm_port = platform_get_drvdata(pdev);
+
+ platform_set_drvdata(pdev, NULL);
+
+ uart_remove_one_port(&efm32_usart_reg, &efm_port->port);
+
+ if (pdev->id >= 0 && pdev->id < ARRAY_SIZE(efm32_usart_ports))
+ efm32_usart_ports[pdev->id] = NULL;
+
+ kfree(efm_port);
+
+ return 0;
+}
+
+static struct of_device_id efm32_usart_dt_ids[] = {
+ {
+ .compatible = "efm32,usart",
+ }, {
+ /* sentinel */
+ }
+};
+MODULE_DEVICE_TABLE(of, efm32_usart_dt_ids);
+
+static struct platform_driver efm32_usart_driver = {
+ .probe = efm32_usart_probe,
+ .remove = __devexit_p(efm32_usart_remove),
+
+ .driver = {
+ .name = DRIVER_NAME,
+ .owner = THIS_MODULE,
+ .of_match_table = efm32_usart_dt_ids,
+ },
+};
+
+static int __init efm32_usart_init(void)
+{
+ int ret;
+
+ ret = uart_register_driver(&efm32_usart_reg);
+ if (ret)
+ return ret;
+
+ ret = platform_driver_register(&efm32_usart_driver);
+ if (ret)
+ uart_unregister_driver(&efm32_usart_reg);
+
+ pr_info("EFM32 USART driver\n");
+
+ return ret;
+}
+module_init(efm32_usart_init);
+
+static void __exit efm32_usart_exit(void)
+{
+ platform_driver_unregister(&efm32_usart_driver);
+ uart_unregister_driver(&efm32_usart_reg);
+}
+
+MODULE_AUTHOR("Uwe Kleine-Koenig <u.kleine-koenig at pengutronix.de>");
+MODULE_DESCRIPTION("EFM32 USART driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:" DRIVER_NAME);
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index eadf33d..eb45d4d 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -207,6 +207,8 @@
/* Xilinx PSS UART */
#define PORT_XUARTPS 98
+#define PORT_EFMUSART 99
+
#ifdef __KERNEL__
#include <linux/compiler.h>
--
1.7.7.3
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