summaryrefslogtreecommitdiffstats
path: root/drivers/tty/serial/efm32-uart.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/tty/serial/efm32-uart.c')
-rw-r--r--drivers/tty/serial/efm32-uart.c852
1 files changed, 852 insertions, 0 deletions
diff --git a/drivers/tty/serial/efm32-uart.c b/drivers/tty/serial/efm32-uart.c
new file mode 100644
index 000000000..f12f29cf4
--- /dev/null
+++ b/drivers/tty/serial/efm32-uart.c
@@ -0,0 +1,852 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/io.h>
+#include <linux/platform_device.h>
+#include <linux/console.h>
+#include <linux/sysrq.h>
+#include <linux/serial_core.h>
+#include <linux/tty_flip.h>
+#include <linux/slab.h>
+#include <linux/clk.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+
+#include <linux/platform_data/efm32-uart.h>
+
+#define DRIVER_NAME "efm32-uart"
+#define DEV_NAME "ttyefm"
+
+#define UARTn_CTRL 0x00
+#define UARTn_CTRL_SYNC 0x0001
+#define UARTn_CTRL_TXBIL 0x1000
+
+#define UARTn_FRAME 0x04
+#define UARTn_FRAME_DATABITS__MASK 0x000f
+#define UARTn_FRAME_DATABITS(n) ((n) - 3)
+#define UARTn_FRAME_PARITY__MASK 0x0300
+#define UARTn_FRAME_PARITY_NONE 0x0000
+#define UARTn_FRAME_PARITY_EVEN 0x0200
+#define UARTn_FRAME_PARITY_ODD 0x0300
+#define UARTn_FRAME_STOPBITS_HALF 0x0000
+#define UARTn_FRAME_STOPBITS_ONE 0x1000
+#define UARTn_FRAME_STOPBITS_TWO 0x3000
+
+#define UARTn_CMD 0x0c
+#define UARTn_CMD_RXEN 0x0001
+#define UARTn_CMD_RXDIS 0x0002
+#define UARTn_CMD_TXEN 0x0004
+#define UARTn_CMD_TXDIS 0x0008
+
+#define UARTn_STATUS 0x10
+#define UARTn_STATUS_TXENS 0x0002
+#define UARTn_STATUS_TXC 0x0020
+#define UARTn_STATUS_TXBL 0x0040
+#define UARTn_STATUS_RXDATAV 0x0080
+
+#define UARTn_CLKDIV 0x14
+
+#define UARTn_RXDATAX 0x18
+#define UARTn_RXDATAX_RXDATA__MASK 0x01ff
+#define UARTn_RXDATAX_PERR 0x4000
+#define UARTn_RXDATAX_FERR 0x8000
+/*
+ * This is a software only flag used for ignore_status_mask and
+ * read_status_mask! It's used for breaks that the hardware doesn't report
+ * explicitly.
+ */
+#define SW_UARTn_RXDATAX_BERR 0x2000
+
+#define UARTn_TXDATA 0x34
+
+#define UARTn_IF 0x40
+#define UARTn_IF_TXC 0x0001
+#define UARTn_IF_TXBL 0x0002
+#define UARTn_IF_RXDATAV 0x0004
+#define UARTn_IF_RXOF 0x0010
+
+#define UARTn_IFS 0x44
+#define UARTn_IFC 0x48
+#define UARTn_IEN 0x4c
+
+#define UARTn_ROUTE 0x54
+#define UARTn_ROUTE_LOCATION__MASK 0x0700
+#define UARTn_ROUTE_LOCATION(n) (((n) << 8) & UARTn_ROUTE_LOCATION__MASK)
+#define UARTn_ROUTE_RXPEN 0x0001
+#define UARTn_ROUTE_TXPEN 0x0002
+
+struct efm32_uart_port {
+ struct uart_port port;
+ unsigned int txirq;
+ struct clk *clk;
+ struct efm32_uart_pdata pdata;
+};
+#define to_efm_port(_port) container_of(_port, struct efm32_uart_port, port)
+#define efm_debug(efm_port, format, arg...) \
+ dev_dbg(efm_port->port.dev, format, ##arg)
+
+static void efm32_uart_write32(struct efm32_uart_port *efm_port,
+ u32 value, unsigned offset)
+{
+ writel_relaxed(value, efm_port->port.membase + offset);
+}
+
+static u32 efm32_uart_read32(struct efm32_uart_port *efm_port,
+ unsigned offset)
+{
+ return readl_relaxed(efm_port->port.membase + offset);
+}
+
+static unsigned int efm32_uart_tx_empty(struct uart_port *port)
+{
+ struct efm32_uart_port *efm_port = to_efm_port(port);
+ u32 status = efm32_uart_read32(efm_port, UARTn_STATUS);
+
+ if (status & UARTn_STATUS_TXC)
+ return TIOCSER_TEMT;
+ else
+ return 0;
+}
+
+static void efm32_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+ /* sorry, neither handshaking lines nor loop functionallity */
+}
+
+static unsigned int efm32_uart_get_mctrl(struct uart_port *port)
+{
+ /* sorry, no handshaking lines available */
+ return TIOCM_CAR | TIOCM_CTS | TIOCM_DSR;
+}
+
+static void efm32_uart_stop_tx(struct uart_port *port)
+{
+ struct efm32_uart_port *efm_port = to_efm_port(port);
+ u32 ien = efm32_uart_read32(efm_port, UARTn_IEN);
+
+ efm32_uart_write32(efm_port, UARTn_CMD_TXDIS, UARTn_CMD);
+ ien &= ~(UARTn_IF_TXC | UARTn_IF_TXBL);
+ efm32_uart_write32(efm_port, ien, UARTn_IEN);
+}
+
+static void efm32_uart_tx_chars(struct efm32_uart_port *efm_port)
+{
+ struct uart_port *port = &efm_port->port;
+ struct circ_buf *xmit = &port->state->xmit;
+
+ while (efm32_uart_read32(efm_port, UARTn_STATUS) &
+ UARTn_STATUS_TXBL) {
+ if (port->x_char) {
+ port->icount.tx++;
+ efm32_uart_write32(efm_port, port->x_char,
+ UARTn_TXDATA);
+ port->x_char = 0;
+ continue;
+ }
+ if (!uart_circ_empty(xmit) && !uart_tx_stopped(port)) {
+ port->icount.tx++;
+ efm32_uart_write32(efm_port, xmit->buf[xmit->tail],
+ UARTn_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_uart_read32(efm_port, UARTn_STATUS) &
+ UARTn_STATUS_TXC)
+ efm32_uart_stop_tx(port);
+}
+
+static void efm32_uart_start_tx(struct uart_port *port)
+{
+ struct efm32_uart_port *efm_port = to_efm_port(port);
+ u32 ien;
+
+ efm32_uart_write32(efm_port,
+ UARTn_IF_TXBL | UARTn_IF_TXC, UARTn_IFC);
+ ien = efm32_uart_read32(efm_port, UARTn_IEN);
+ efm32_uart_write32(efm_port,
+ ien | UARTn_IF_TXBL | UARTn_IF_TXC, UARTn_IEN);
+ efm32_uart_write32(efm_port, UARTn_CMD_TXEN, UARTn_CMD);
+
+ efm32_uart_tx_chars(efm_port);
+}
+
+static void efm32_uart_stop_rx(struct uart_port *port)
+{
+ struct efm32_uart_port *efm_port = to_efm_port(port);
+
+ efm32_uart_write32(efm_port, UARTn_CMD_RXDIS, UARTn_CMD);
+}
+
+static void efm32_uart_break_ctl(struct uart_port *port, int ctl)
+{
+ /* not possible without fiddling with gpios */
+}
+
+static void efm32_uart_rx_chars(struct efm32_uart_port *efm_port)
+{
+ struct uart_port *port = &efm_port->port;
+
+ while (efm32_uart_read32(efm_port, UARTn_STATUS) &
+ UARTn_STATUS_RXDATAV) {
+ u32 rxdata = efm32_uart_read32(efm_port, UARTn_RXDATAX);
+ int flag = 0;
+
+ /*
+ * This is a reserved bit and I only saw it read as 0. But to be
+ * sure not to be confused too much by new devices adhere to the
+ * warning in the reference manual that reserved bits might
+ * read as 1 in the future.
+ */
+ rxdata &= ~SW_UARTn_RXDATAX_BERR;
+
+ port->icount.rx++;
+
+ if ((rxdata & UARTn_RXDATAX_FERR) &&
+ !(rxdata & UARTn_RXDATAX_RXDATA__MASK)) {
+ rxdata |= SW_UARTn_RXDATAX_BERR;
+ port->icount.brk++;
+ if (uart_handle_break(port))
+ continue;
+ } else if (rxdata & UARTn_RXDATAX_PERR)
+ port->icount.parity++;
+ else if (rxdata & UARTn_RXDATAX_FERR)
+ port->icount.frame++;
+
+ rxdata &= port->read_status_mask;
+
+ if (rxdata & SW_UARTn_RXDATAX_BERR)
+ flag = TTY_BREAK;
+ else if (rxdata & UARTn_RXDATAX_PERR)
+ flag = TTY_PARITY;
+ else if (rxdata & UARTn_RXDATAX_FERR)
+ flag = TTY_FRAME;
+ else if (uart_handle_sysrq_char(port,
+ rxdata & UARTn_RXDATAX_RXDATA__MASK))
+ continue;
+
+ if ((rxdata & port->ignore_status_mask) == 0)
+ tty_insert_flip_char(&port->state->port,
+ rxdata & UARTn_RXDATAX_RXDATA__MASK, flag);
+ }
+}
+
+static irqreturn_t efm32_uart_rxirq(int irq, void *data)
+{
+ struct efm32_uart_port *efm_port = data;
+ u32 irqflag = efm32_uart_read32(efm_port, UARTn_IF);
+ int handled = IRQ_NONE;
+ struct uart_port *port = &efm_port->port;
+ struct tty_port *tport = &port->state->port;
+
+ spin_lock(&port->lock);
+
+ if (irqflag & UARTn_IF_RXDATAV) {
+ efm32_uart_write32(efm_port, UARTn_IF_RXDATAV, UARTn_IFC);
+ efm32_uart_rx_chars(efm_port);
+
+ handled = IRQ_HANDLED;
+ }
+
+ if (irqflag & UARTn_IF_RXOF) {
+ efm32_uart_write32(efm_port, UARTn_IF_RXOF, UARTn_IFC);
+ port->icount.overrun++;
+ tty_insert_flip_char(tport, 0, TTY_OVERRUN);
+
+ handled = IRQ_HANDLED;
+ }
+
+ spin_unlock(&port->lock);
+
+ tty_flip_buffer_push(tport);
+
+ return handled;
+}
+
+static irqreturn_t efm32_uart_txirq(int irq, void *data)
+{
+ struct efm32_uart_port *efm_port = data;
+ u32 irqflag = efm32_uart_read32(efm_port, UARTn_IF);
+
+ /* TXBL doesn't need to be cleared */
+ if (irqflag & UARTn_IF_TXC)
+ efm32_uart_write32(efm_port, UARTn_IF_TXC, UARTn_IFC);
+
+ if (irqflag & (UARTn_IF_TXC | UARTn_IF_TXBL)) {
+ efm32_uart_tx_chars(efm_port);
+ return IRQ_HANDLED;
+ } else
+ return IRQ_NONE;
+}
+
+static int efm32_uart_startup(struct uart_port *port)
+{
+ struct efm32_uart_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 configured location */
+ efm32_uart_write32(efm_port,
+ UARTn_ROUTE_LOCATION(efm_port->pdata.location) |
+ UARTn_ROUTE_RXPEN | UARTn_ROUTE_TXPEN,
+ UARTn_ROUTE);
+
+ ret = request_irq(port->irq, efm32_uart_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_uart_write32(efm_port, 0, UARTn_IEN);
+
+ ret = request_irq(efm_port->txirq, efm32_uart_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_uart_write32(efm_port,
+ UARTn_IF_RXDATAV | UARTn_IF_RXOF, UARTn_IEN);
+ efm32_uart_write32(efm_port, UARTn_CMD_RXEN, UARTn_CMD);
+ }
+
+err_clk_enable:
+ return ret;
+}
+
+static void efm32_uart_shutdown(struct uart_port *port)
+{
+ struct efm32_uart_port *efm_port = to_efm_port(port);
+
+ efm32_uart_write32(efm_port, 0, UARTn_IEN);
+ free_irq(port->irq, efm_port);
+
+ clk_disable(efm_port->clk);
+}
+
+static void efm32_uart_set_termios(struct uart_port *port,
+ struct ktermios *new, struct ktermios *old)
+{
+ struct efm32_uart_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 |= UARTn_FRAME_DATABITS(5);
+ break;
+ case CS6:
+ frame |= UARTn_FRAME_DATABITS(6);
+ break;
+ case CS7:
+ frame |= UARTn_FRAME_DATABITS(7);
+ break;
+ case CS8:
+ frame |= UARTn_FRAME_DATABITS(8);
+ break;
+ }
+
+ if (new->c_cflag & CSTOPB)
+ /* the receiver only verifies the first stop bit */
+ frame |= UARTn_FRAME_STOPBITS_TWO;
+ else
+ frame |= UARTn_FRAME_STOPBITS_ONE;
+
+ if (new->c_cflag & PARENB) {
+ if (new->c_cflag & PARODD)
+ frame |= UARTn_FRAME_PARITY_ODD;
+ else
+ frame |= UARTn_FRAME_PARITY_EVEN;
+ } else
+ frame |= UARTn_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_uart_write32(efm_port,
+ UARTn_CMD_TXDIS | UARTn_CMD_RXDIS, UARTn_CMD);
+
+ port->read_status_mask = UARTn_RXDATAX_RXDATA__MASK;
+ if (new->c_iflag & INPCK)
+ port->read_status_mask |=
+ UARTn_RXDATAX_FERR | UARTn_RXDATAX_PERR;
+ if (new->c_iflag & (IGNBRK | BRKINT | PARMRK))
+ port->read_status_mask |= SW_UARTn_RXDATAX_BERR;
+
+ port->ignore_status_mask = 0;
+ if (new->c_iflag & IGNPAR)
+ port->ignore_status_mask |=
+ UARTn_RXDATAX_FERR | UARTn_RXDATAX_PERR;
+ if (new->c_iflag & IGNBRK)
+ port->ignore_status_mask |= SW_UARTn_RXDATAX_BERR;
+
+ uart_update_timeout(port, new->c_cflag, baud);
+
+ efm32_uart_write32(efm_port, UARTn_CTRL_TXBIL, UARTn_CTRL);
+ efm32_uart_write32(efm_port, frame, UARTn_FRAME);
+ efm32_uart_write32(efm_port, clkdiv, UARTn_CLKDIV);
+
+ efm32_uart_write32(efm_port, UARTn_CMD_TXEN | UARTn_CMD_RXEN,
+ UARTn_CMD);
+
+ spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static const char *efm32_uart_type(struct uart_port *port)
+{
+ return port->type == PORT_EFMUART ? "efm32-uart" : NULL;
+}
+
+static void efm32_uart_release_port(struct uart_port *port)
+{
+ struct efm32_uart_port *efm_port = to_efm_port(port);
+
+ clk_unprepare(efm_port->clk);
+ clk_put(efm_port->clk);
+ iounmap(port->membase);
+}
+
+static int efm32_uart_request_port(struct uart_port *port)
+{
+ struct efm32_uart_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_uart_config_port(struct uart_port *port, int type)
+{
+ if (type & UART_CONFIG_TYPE &&
+ !efm32_uart_request_port(port))
+ port->type = PORT_EFMUART;
+}
+
+static int efm32_uart_verify_port(struct uart_port *port,
+ struct serial_struct *serinfo)
+{
+ int ret = 0;
+
+ if (serinfo->type != PORT_UNKNOWN && serinfo->type != PORT_EFMUART)
+ ret = -EINVAL;
+
+ return ret;
+}
+
+static const struct uart_ops efm32_uart_pops = {
+ .tx_empty = efm32_uart_tx_empty,
+ .set_mctrl = efm32_uart_set_mctrl,
+ .get_mctrl = efm32_uart_get_mctrl,
+ .stop_tx = efm32_uart_stop_tx,
+ .start_tx = efm32_uart_start_tx,
+ .stop_rx = efm32_uart_stop_rx,
+ .break_ctl = efm32_uart_break_ctl,
+ .startup = efm32_uart_startup,
+ .shutdown = efm32_uart_shutdown,
+ .set_termios = efm32_uart_set_termios,
+ .type = efm32_uart_type,
+ .release_port = efm32_uart_release_port,
+ .request_port = efm32_uart_request_port,
+ .config_port = efm32_uart_config_port,
+ .verify_port = efm32_uart_verify_port,
+};
+
+static struct efm32_uart_port *efm32_uart_ports[5];
+
+#ifdef CONFIG_SERIAL_EFM32_UART_CONSOLE
+static void efm32_uart_console_putchar(struct uart_port *port, int ch)
+{
+ struct efm32_uart_port *efm_port = to_efm_port(port);
+ unsigned int timeout = 0x400;
+ u32 status;
+
+ while (1) {
+ status = efm32_uart_read32(efm_port, UARTn_STATUS);
+
+ if (status & UARTn_STATUS_TXBL)
+ break;
+ if (!timeout--)
+ return;
+ }
+ efm32_uart_write32(efm_port, ch, UARTn_TXDATA);
+}
+
+static void efm32_uart_console_write(struct console *co, const char *s,
+ unsigned int count)
+{
+ struct efm32_uart_port *efm_port = efm32_uart_ports[co->index];
+ u32 status = efm32_uart_read32(efm_port, UARTn_STATUS);
+ unsigned int timeout = 0x400;
+
+ if (!(status & UARTn_STATUS_TXENS))
+ efm32_uart_write32(efm_port, UARTn_CMD_TXEN, UARTn_CMD);
+
+ uart_console_write(&efm_port->port, s, count,
+ efm32_uart_console_putchar);
+
+ /* Wait for the transmitter to become empty */
+ while (1) {
+ u32 status = efm32_uart_read32(efm_port, UARTn_STATUS);
+ if (status & UARTn_STATUS_TXC)
+ break;
+ if (!timeout--)
+ break;
+ }
+
+ if (!(status & UARTn_STATUS_TXENS))
+ efm32_uart_write32(efm_port, UARTn_CMD_TXDIS, UARTn_CMD);
+}
+
+static void efm32_uart_console_get_options(struct efm32_uart_port *efm_port,
+ int *baud, int *parity, int *bits)
+{
+ u32 ctrl = efm32_uart_read32(efm_port, UARTn_CTRL);
+ u32 route, clkdiv, frame;
+
+ if (ctrl & UARTn_CTRL_SYNC)
+ /* not operating in async mode */
+ return;
+
+ route = efm32_uart_read32(efm_port, UARTn_ROUTE);
+ if (!(route & UARTn_ROUTE_TXPEN))
+ /* tx pin not routed */
+ return;
+
+ clkdiv = efm32_uart_read32(efm_port, UARTn_CLKDIV);
+
+ *baud = DIV_ROUND_CLOSEST(4 * efm_port->port.uartclk,
+ 16 * (4 + (clkdiv >> 6)));
+
+ frame = efm32_uart_read32(efm_port, UARTn_FRAME);
+ switch (frame & UARTn_FRAME_PARITY__MASK) {
+ case UARTn_FRAME_PARITY_ODD:
+ *parity = 'o';
+ break;
+ case UARTn_FRAME_PARITY_EVEN:
+ *parity = 'e';
+ break;
+ default:
+ *parity = 'n';
+ }
+
+ *bits = (frame & UARTn_FRAME_DATABITS__MASK) -
+ UARTn_FRAME_DATABITS(4) + 4;
+
+ efm_debug(efm_port, "get_opts: options=%d%c%d\n",
+ *baud, *parity, *bits);
+}
+
+static int efm32_uart_console_setup(struct console *co, char *options)
+{
+ struct efm32_uart_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_uart_ports)) {
+ unsigned i;
+ for (i = 0; i < ARRAY_SIZE(efm32_uart_ports); ++i) {
+ if (efm32_uart_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_uart_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_uart_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_uart_reg;
+
+static struct console efm32_uart_console = {
+ .name = DEV_NAME,
+ .write = efm32_uart_console_write,
+ .device = uart_console_device,
+ .setup = efm32_uart_console_setup,
+ .flags = CON_PRINTBUFFER,
+ .index = -1,
+ .data = &efm32_uart_reg,
+};
+
+#else
+#define efm32_uart_console (*(struct console *)NULL)
+#endif /* ifdef CONFIG_SERIAL_EFM32_UART_CONSOLE / else */
+
+static struct uart_driver efm32_uart_reg = {
+ .owner = THIS_MODULE,
+ .driver_name = DRIVER_NAME,
+ .dev_name = DEV_NAME,
+ .nr = ARRAY_SIZE(efm32_uart_ports),
+ .cons = &efm32_uart_console,
+};
+
+static int efm32_uart_probe_dt(struct platform_device *pdev,
+ struct efm32_uart_port *efm_port)
+{
+ struct device_node *np = pdev->dev.of_node;
+ u32 location;
+ int ret;
+
+ if (!np)
+ return 1;
+
+ ret = of_property_read_u32(np, "energymicro,location", &location);
+
+ if (ret)
+ /* fall back to wrongly namespaced property */
+ ret = of_property_read_u32(np, "efm32,location", &location);
+
+ if (ret)
+ /* fall back to old and (wrongly) generic property "location" */
+ ret = of_property_read_u32(np, "location", &location);
+
+ if (!ret) {
+ if (location > 5) {
+ dev_err(&pdev->dev, "invalid location\n");
+ return -EINVAL;
+ }
+ efm_debug(efm_port, "using location %u\n", location);
+ efm_port->pdata.location = location;
+ } else {
+ efm_debug(efm_port, "fall back to location 0\n");
+ }
+
+ 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 efm32_uart_probe(struct platform_device *pdev)
+{
+ struct efm32_uart_port *efm_port;
+ struct resource *res;
+ unsigned int line;
+ 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_EFMUART;
+ efm_port->port.iotype = UPIO_MEM32;
+ efm_port->port.fifosize = 2;
+ efm_port->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_EFM32_UART_CONSOLE);
+ efm_port->port.ops = &efm32_uart_pops;
+ efm_port->port.flags = UPF_BOOT_AUTOCONF;
+
+ ret = efm32_uart_probe_dt(pdev, efm_port);
+ if (ret > 0) {
+ /* not created by device tree */
+ const struct efm32_uart_pdata *pdata = dev_get_platdata(&pdev->dev);
+
+ efm_port->port.line = pdev->id;
+
+ if (pdata)
+ efm_port->pdata = *pdata;
+ } else if (ret < 0)
+ goto err_probe_dt;
+
+ line = efm_port->port.line;
+
+ if (line >= 0 && line < ARRAY_SIZE(efm32_uart_ports))
+ efm32_uart_ports[line] = efm_port;
+
+ ret = uart_add_one_port(&efm32_uart_reg, &efm_port->port);
+ if (ret) {
+ dev_dbg(&pdev->dev, "failed to add port: %d\n", ret);
+
+ if (line >= 0 && line < ARRAY_SIZE(efm32_uart_ports))
+ efm32_uart_ports[line] = NULL;
+err_probe_dt:
+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 efm32_uart_remove(struct platform_device *pdev)
+{
+ struct efm32_uart_port *efm_port = platform_get_drvdata(pdev);
+ unsigned int line = efm_port->port.line;
+
+ uart_remove_one_port(&efm32_uart_reg, &efm_port->port);
+
+ if (line >= 0 && line < ARRAY_SIZE(efm32_uart_ports))
+ efm32_uart_ports[line] = NULL;
+
+ kfree(efm_port);
+
+ return 0;
+}
+
+static const struct of_device_id efm32_uart_dt_ids[] = {
+ {
+ .compatible = "energymicro,efm32-uart",
+ }, {
+ /* doesn't follow the "vendor,device" scheme, don't use */
+ .compatible = "efm32,uart",
+ }, {
+ /* sentinel */
+ }
+};
+MODULE_DEVICE_TABLE(of, efm32_uart_dt_ids);
+
+static struct platform_driver efm32_uart_driver = {
+ .probe = efm32_uart_probe,
+ .remove = efm32_uart_remove,
+
+ .driver = {
+ .name = DRIVER_NAME,
+ .of_match_table = efm32_uart_dt_ids,
+ },
+};
+
+static int __init efm32_uart_init(void)
+{
+ int ret;
+
+ ret = uart_register_driver(&efm32_uart_reg);
+ if (ret)
+ return ret;
+
+ ret = platform_driver_register(&efm32_uart_driver);
+ if (ret)
+ uart_unregister_driver(&efm32_uart_reg);
+
+ pr_info("EFM32 UART/USART driver\n");
+
+ return ret;
+}
+module_init(efm32_uart_init);
+
+static void __exit efm32_uart_exit(void)
+{
+ platform_driver_unregister(&efm32_uart_driver);
+ uart_unregister_driver(&efm32_uart_reg);
+}
+module_exit(efm32_uart_exit);
+
+MODULE_AUTHOR("Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>");
+MODULE_DESCRIPTION("EFM32 UART/USART driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:" DRIVER_NAME);