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|
#if defined(CONFIG_SERIAL_EFM32_UART_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
#define SUPPORT_SYSRQ
#endif
#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_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;
};
#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_enable_ms(struct uart_port *port)
{
/* no handshake lines, no modem status interrupts */
}
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 reserverd 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;
struct tty_struct *tty;
spin_lock(&port->lock);
tty = tty_kref_get(tport->tty);
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;
}
if (tty) {
tty_flip_buffer_push(tty);
tty_kref_put(tty);
}
spin_unlock(&port->lock);
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);
u32 location = 0;
struct efm32_uart_pdata *pdata = dev_get_platdata(port->dev);
int ret;
if (pdata)
location = UARTn_ROUTE_LOCATION(pdata->location);
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, 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 & (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 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,
.enable_ms = efm32_uart_enable_ms,
.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);
if (frame & UARTn_FRAME_PARITY_ODD)
*parity = 'o';
else if (frame & UARTn_FRAME_PARITY_EVEN)
*parity = 'e';
else
*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;
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 efm32_uart_probe(struct platform_device *pdev)
{
struct efm32_uart_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_EFMUART;
efm_port->port.iotype = UPIO_MEM32;
efm_port->port.fifosize = 2;
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 */
efm_port->port.line = pdev->id;
if (efm_port->port.line >= 0 &&
efm_port->port.line < ARRAY_SIZE(efm32_uart_ports))
efm32_uart_ports[efm_port->port.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 (pdev->id >= 0 && pdev->id < ARRAY_SIZE(efm32_uart_ports))
efm32_uart_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 efm32_uart_remove(struct platform_device *pdev)
{
struct efm32_uart_port *efm_port = platform_get_drvdata(pdev);
platform_set_drvdata(pdev, NULL);
uart_remove_one_port(&efm32_uart_reg, &efm_port->port);
if (pdev->id >= 0 && pdev->id < ARRAY_SIZE(efm32_uart_ports))
efm32_uart_ports[pdev->id] = NULL;
kfree(efm_port);
return 0;
}
static struct of_device_id efm32_uart_dt_ids[] = {
{
.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,
.owner = THIS_MODULE,
.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_AUTHOR("Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>");
MODULE_DESCRIPTION("EFM32 UART/USART driver");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:" DRIVER_NAME);
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