// SPDX-License-Identifier: GPL-2.0
/*
* MEN 16z135 High Speed UART
*
* Copyright (C) 2014 MEN Mikroelektronik GmbH (www.men.de)
* Author: Johannes Thumshirn <[email protected]>
*/
#define pr_fmt(fmt) KBUILD_MODNAME ":" fmt
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/serial_core.h>
#include <linux/ioport.h>
#include <linux/io.h>
#include <linux/tty_flip.h>
#include <linux/bitops.h>
#include <linux/mcb.h>
#define MEN_Z135_MAX_PORTS 12
#define MEN_Z135_BASECLK 29491200
#define MEN_Z135_FIFO_SIZE 1024
#define MEN_Z135_FIFO_WATERMARK 1020
#define MEN_Z135_STAT_REG 0x0
#define MEN_Z135_RX_RAM 0x4
#define MEN_Z135_TX_RAM 0x400
#define MEN_Z135_RX_CTRL 0x800
#define MEN_Z135_TX_CTRL 0x804
#define MEN_Z135_CONF_REG 0x808
#define MEN_Z135_UART_FREQ 0x80c
#define MEN_Z135_BAUD_REG 0x810
#define MEN_Z135_TIMEOUT 0x814
#define IRQ_ID(x) ((x) & 0x1f)
#define MEN_Z135_IER_RXCIEN BIT(0) /* RX Space IRQ */
#define MEN_Z135_IER_TXCIEN BIT(1) /* TX Space IRQ */
#define MEN_Z135_IER_RLSIEN BIT(2) /* Receiver Line Status IRQ */
#define MEN_Z135_IER_MSIEN BIT(3) /* Modem Status IRQ */
#define MEN_Z135_ALL_IRQS (MEN_Z135_IER_RXCIEN \
| MEN_Z135_IER_RLSIEN \
| MEN_Z135_IER_MSIEN \
| MEN_Z135_IER_TXCIEN)
#define MEN_Z135_MCR_DTR BIT(24)
#define MEN_Z135_MCR_RTS BIT(25)
#define MEN_Z135_MCR_OUT1 BIT(26)
#define MEN_Z135_MCR_OUT2 BIT(27)
#define MEN_Z135_MCR_LOOP BIT(28)
#define MEN_Z135_MCR_RCFC BIT(29)
#define MEN_Z135_MSR_DCTS BIT(0)
#define MEN_Z135_MSR_DDSR BIT(1)
#define MEN_Z135_MSR_DRI BIT(2)
#define MEN_Z135_MSR_DDCD BIT(3)
#define MEN_Z135_MSR_CTS BIT(4)
#define MEN_Z135_MSR_DSR BIT(5)
#define MEN_Z135_MSR_RI BIT(6)
#define MEN_Z135_MSR_DCD BIT(7)
#define MEN_Z135_LCR_SHIFT 8 /* LCR shift mask */
#define MEN_Z135_WL5 0 /* CS5 */
#define MEN_Z135_WL6 1 /* CS6 */
#define MEN_Z135_WL7 2 /* CS7 */
#define MEN_Z135_WL8 3 /* CS8 */
#define MEN_Z135_STB_SHIFT 2 /* Stopbits */
#define MEN_Z135_NSTB1 0
#define MEN_Z135_NSTB2 1
#define MEN_Z135_PEN_SHIFT 3 /* Parity enable */
#define MEN_Z135_PAR_DIS 0
#define MEN_Z135_PAR_ENA 1
#define MEN_Z135_PTY_SHIFT 4 /* Parity type */
#define MEN_Z135_PTY_ODD 0
#define MEN_Z135_PTY_EVN 1
#define MEN_Z135_LSR_DR BIT(0)
#define MEN_Z135_LSR_OE BIT(1)
#define MEN_Z135_LSR_PE BIT(2)
#define MEN_Z135_LSR_FE BIT(3)
#define MEN_Z135_LSR_BI BIT(4)
#define MEN_Z135_LSR_THEP BIT(5)
#define MEN_Z135_LSR_TEXP BIT(6)
#define MEN_Z135_LSR_RXFIFOERR BIT(7)
#define MEN_Z135_IRQ_ID_RLS BIT(0)
#define MEN_Z135_IRQ_ID_RDA BIT(1)
#define MEN_Z135_IRQ_ID_CTI BIT(2)
#define MEN_Z135_IRQ_ID_TSA BIT(3)
#define MEN_Z135_IRQ_ID_MST BIT(4)
#define LCR(x) (((x) >> MEN_Z135_LCR_SHIFT) & 0xff)
#define BYTES_TO_ALIGN(x) ((x) & 0x3)
static int line;
static int txlvl = 5;
module_param(txlvl, int, S_IRUGO);
MODULE_PARM_DESC(txlvl, "TX IRQ trigger level 0-7, default 5 (128 byte)");
static int rxlvl = 6;
module_param(rxlvl, int, S_IRUGO);
MODULE_PARM_DESC(rxlvl, "RX IRQ trigger level 0-7, default 6 (256 byte)");
static int align;
module_param(align, int, S_IRUGO);
MODULE_PARM_DESC(align, "Keep hardware FIFO write pointer aligned, default 0");
static uint rx_timeout;
module_param(rx_timeout, uint, S_IRUGO);
MODULE_PARM_DESC(rx_timeout, "RX timeout. "
"Timeout in seconds = (timeout_reg * baud_reg * 4) / freq_reg");
struct men_z135_port {
struct uart_port port;
struct mcb_device *mdev;
struct resource *mem;
unsigned char *rxbuf;
u32 stat_reg;
spinlock_t lock;
bool automode;
};
#define to_men_z135(port) container_of((port), struct men_z135_port, port)
/**
* men_z135_reg_set() - Set value in register
* @uart: The UART port
* @addr: Register address
* @val: value to set
*/
static inline void men_z135_reg_set(struct men_z135_port *uart,
u32 addr, u32 val)
{
struct uart_port *port = &uart->port;
unsigned long flags;
u32 reg;
spin_lock_irqsave(&uart->lock, flags);
reg = ioread32(port->membase + addr);
reg |= val;
iowrite32(reg, port->membase + addr);
spin_unlock_irqrestore(&uart->lock, flags);
}
/**
* men_z135_reg_clr() - Unset value in register
* @uart: The UART port
* @addr: Register address
* @val: value to clear
*/
static void men_z135_reg_clr(struct men_z135_port *uart,
u32 addr, u32 val)
{
struct uart_port *port = &uart->port;
unsigned long flags;
u32 reg;
spin_lock_irqsave(&uart->lock, flags);
reg = ioread32(port->membase + addr);
reg &= ~val;
iowrite32(reg, port->membase + addr);
spin_unlock_irqrestore(&uart->lock, flags);
}
/**
* men_z135_handle_modem_status() - Handle change of modem status
* @uart: The UART port
*
* Handle change of modem status register. This is done by reading the "delta"
* versions of DCD (Data Carrier Detect) and CTS (Clear To Send).
*/
static void men_z135_handle_modem_status(struct men_z135_port *uart)
{
u8 msr;
msr = (uart->stat_reg >> 8) & 0xff;
if (msr & MEN_Z135_MSR_DDCD)
uart_handle_dcd_change(&uart->port,
msr & MEN_Z135_MSR_DCD);
if (msr & MEN_Z135_MSR_DCTS)
uart_handle_cts_change(&uart->port,
msr & MEN_Z135_MSR_CTS);
}
static void men_z135_handle_lsr(struct men_z135_port *uart)
{
struct uart_port *port = &uart->port;
u8 lsr;
lsr = (uart->stat_reg >> 16) & 0xff;
if (lsr & MEN_Z135_LSR_OE)
port->icount.overrun++;
if (lsr & MEN_Z135_LSR_PE)
port->icount.parity++;
if (lsr & MEN_Z135_LSR_FE)
port->icount.frame++;
if (lsr & MEN_Z135_LSR_BI) {
port->icount.brk++;
uart_handle_break(port);
}
}
/**
* get_rx_fifo_content() - Get the number of bytes in RX FIFO
* @uart: The UART port
*
* Read RXC register from hardware and return current FIFO fill size.
*/
static u16 get_rx_fifo_content(struct men_z135_port *uart)
{
struct uart_port *port = &uart->port;
u32 stat_reg;
u16 rxc;
u8 rxc_lo;
u8 rxc_hi;
stat_reg = ioread32(port->membase + MEN_Z135_STAT_REG);
rxc_lo = stat_reg >> 24;
rxc_hi = (stat_reg & 0xC0) >> 6;
rxc = rxc_lo | (rxc_hi << 8);
return rxc;
}
/**
* men_z135_handle_rx() - RX tasklet routine
* @uart: Pointer to struct men_z135_port
*
* Copy from RX FIFO and acknowledge number of bytes copied.
*/
static void men_z135_handle_rx(struct men_z135_port *uart)
{
struct uart_port *port = &uart->port;
struct tty_port *tport = &port->state->port;
int copied;
u16 size;
int room;
size = get_rx_fifo_content(uart);
if (size == 0)
return;
/* Avoid accidently accessing TX FIFO instead of RX FIFO. Last
* longword in RX FIFO cannot be read.(0x004-0x3FF)
*/
if (size > MEN_Z135_FIFO_WATERMARK)
size = MEN_Z135_FIFO_WATERMARK;
room = tty_buffer_request_room(tport, size);
if (room != size)
dev_warn(&uart->mdev->dev,
"Not enough room in flip buffer, truncating to %d\n",
room);
if (room == 0)
return;
memcpy_fromio(uart->rxbuf, port->membase + MEN_Z135_RX_RAM, room);
/* Be sure to first copy all data and then acknowledge it */
mb();
iowrite32(room, port->membase + MEN_Z135_RX_CTRL);
copied = tty_insert_flip_string(tport, uart->rxbuf, room);
if (copied != room)
dev_warn(&uart->mdev->dev,
"Only copied %d instead of %d bytes\n",
copied, room);
port->icount.rx += copied;
tty_flip_buffer_push(tport);
}
/**
* men_z135_handle_tx() - TX tasklet routine
* @uart: Pointer to struct men_z135_port
*
*/
static void men_z135_handle_tx(struct men_z135_port *uart)
{
struct uart_port *port = &uart->port;
struct tty_port *tport = &port->state->port;
unsigned char *tail;
unsigned int n, txfree;
u32 txc;
u32 wptr;
int qlen;
if (kfifo_is_empty(&tport->xmit_fifo))
goto out;
if (uart_tx_stopped(port))
goto out;
if (port->x_char)
goto out;
/* calculate bytes to copy */
qlen = kfifo_len(&tport->xmit_fifo);
if (qlen <= 0)
goto out;
wptr = ioread32(port->membase + MEN_Z135_TX_CTRL);
txc = (wptr >> 16) & 0x3ff;
wptr &= 0x3ff;
if (txc > MEN_Z135_FIFO_WATERMARK)
txc = MEN_Z135_FIFO_WATERMARK;
txfree = MEN_Z135_FIFO_WATERMARK - txc;
if (txfree <= 0) {
dev_err(&uart->mdev->dev,
"Not enough room in TX FIFO have %d, need %d\n",
txfree, qlen);
goto irq_en;
}
/* if we're not aligned, it's better to copy only 1 or 2 bytes and
* then the rest.
*/
if (align && qlen >= 3 && BYTES_TO_ALIGN(wptr))
n = 4 - BYTES_TO_ALIGN(wptr);
else if (qlen > txfree)
n = txfree;
else
n = qlen;
if (n <= 0)
goto irq_en;
n = kfifo_out_linear_ptr(&tport->xmit_fifo, &tail,
min_t(unsigned int, UART_XMIT_SIZE, n));
memcpy_toio(port->membase + MEN_Z135_TX_RAM, tail, n);
iowrite32(n & 0x3ff, port->membase + MEN_Z135_TX_CTRL);
uart_xmit_advance(port, n);
if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS)
uart_write_wakeup(port);
irq_en:
if (!kfifo_is_empty(&tport->xmit_fifo))
men_z135_reg_set(uart, MEN_Z135_CONF_REG, MEN_Z135_IER_TXCIEN);
else
men_z135_reg_clr(uart, MEN_Z135_CONF_REG, MEN_Z135_IER_TXCIEN);
out:
return;
}
/**
* men_z135_intr() - Handle legacy IRQs
* @irq: The IRQ number
* @data: Pointer to UART port
*
* Check IIR register to find the cause of the interrupt and handle it.
* It is possible that multiple interrupts reason bits are set and reading
* the IIR is a destructive read, so we always need to check for all possible
* interrupts and handle them.
*/
static irqreturn_t men_z135_intr(int irq, void *data)
{
struct men_z135_port *uart = (struct men_z135_port *)data;
struct uart_port *port = &uart->port;
bool handled = false;
int irq_id;
uart->stat_reg = ioread32(port->membase + MEN_Z135_STAT_REG);
irq_id = IRQ_ID(uart->stat_reg);
if (!irq_id)
goto out;
uart_port_lock(port);
/* It's save to write to IIR[7:6] RXC[9:8] */
iowrite8(irq_id, port->membase + MEN_Z135_STAT_REG);
if (irq_id & MEN_Z135_IRQ_ID_RLS) {
men_z135_handle_lsr(uart);
handled = true;
}
if (irq_id & (MEN_Z135_IRQ_ID_RDA | MEN_Z135_IRQ_ID_CTI)) {
if (irq_id & MEN_Z135_IRQ_ID_CTI)
dev_dbg(&uart->mdev->dev, "Character Timeout Indication\n");
men_z135_handle_rx(uart);
handled = true;
}
if (irq_id & MEN_Z135_IRQ_ID_TSA) {
men_z135_handle_tx(uart);
handled = true;
}
if (irq_id & MEN_Z135_IRQ_ID_MST) {
men_z135_handle_modem_status(uart);
handled = true;
}
uart_port_unlock(port);
out:
return IRQ_RETVAL(handled);
}
/**
* men_z135_request_irq() - Request IRQ for 16z135 core
* @uart: z135 private uart port structure
*
* Request an IRQ for 16z135 to use. First try using MSI, if it fails
* fall back to using legacy interrupts.
*/
static int men_z135_request_irq(struct men_z135_port *uart)
{
struct device *dev = &uart->mdev->dev;
struct uart_port *port = &uart->port;
int err = 0;
err = request_irq(port->irq, men_z135_intr, IRQF_SHARED,
"men_z135_intr", uart);
if (err)
dev_err(dev, "Error %d getting interrupt\n", err);
return err;
}
/**
* men_z135_tx_empty() - Handle tx_empty call
* @port: The UART port
*
* This function tests whether the TX FIFO and shifter for the port
* described by @port is empty.
*/
static unsigned int men_z135_tx_empty(struct uart_port *port)
{
u32 wptr;
u16 txc;
wptr = ioread32(port->membase + MEN_Z135_TX_CTRL);
txc = (wptr >> 16) & 0x3ff;
if (txc == 0)
return TIOCSER_TEMT;
else
return 0;
}
/**
* men_z135_set_mctrl() - Set modem control lines
* @port: The UART port
* @mctrl: The modem control lines
*
* This function sets the modem control lines for a port described by @port
* to the state described by @mctrl
*/
static void men_z135_set_mctrl(struct uart_port *port, unsigned int mctrl)
{
u32 old;
u32 conf_reg;
conf_reg = old = ioread32(port->membase + MEN_Z135_CONF_REG);
if (mctrl & TIOCM_RTS)
conf_reg |= MEN_Z135_MCR_RTS;
else
conf_reg &= ~MEN_Z135_MCR_RTS;
if (mctrl & TIOCM_DTR)
conf_reg |= MEN_Z135_MCR_DTR;
else
conf_reg &= ~MEN_Z135_MCR_DTR;
if (mctrl & TIOCM_OUT1)
conf_reg |= MEN_Z135_MCR_OUT1;
else
conf_reg &= ~MEN_Z135_MCR_OUT1;
if (mctrl & TIOCM_OUT2)
conf_reg |= MEN_Z135_MCR_OUT2;
else
conf_reg &= ~MEN_Z135_MCR_OUT2;
if (mctrl & TIOCM_LOOP)
conf_reg |= MEN_Z135_MCR_LOOP;
else
conf_reg &= ~MEN_Z135_MCR_LOOP;
if (conf_reg != old)
iowrite32(conf_reg, port->membase + MEN_Z135_CONF_REG);
}
/**
* men_z135_get_mctrl() - Get modem control lines
* @port: The UART port
*
* Retruns the current state of modem control inputs.
*/
static unsigned int men_z135_get_mctrl(struct uart_port *port)
{
unsigned int mctrl = 0;
u8 msr;
msr = ioread8(port->membase + MEN_Z135_STAT_REG + 1);
if (msr & MEN_Z135_MSR_CTS)
mctrl |= TIOCM_CTS;
if (msr & MEN_Z135_MSR_DSR)
mctrl |= TIOCM_DSR;
if (msr & MEN_Z135_MSR_RI)
mctrl |= TIOCM_RI;
if (msr & MEN_Z135_MSR_DCD)
mctrl |= TIOCM_CAR;
return mctrl;
}
/**
* men_z135_stop_tx() - Stop transmitting characters
* @port: The UART port
*
* Stop transmitting characters. This might be due to CTS line becomming
* inactive or the tty layer indicating we want to stop transmission due to
* an XOFF character.
*/
static void men_z135_stop_tx(struct uart_port *port)
{
struct men_z135_port *uart = to_men_z135(port);
men_z135_reg_clr(uart, MEN_Z135_CONF_REG, MEN_Z135_IER_TXCIEN);
}
/*
* men_z135_disable_ms() - Disable Modem Status
* port: The UART port
*
* Enable Modem Status IRQ.
*/
static void men_z135_disable_ms(struct uart_port *port)
{
struct men_z135_port *uart = to_men_z135(port);
men_z135_reg_clr(uart, MEN_Z135_CONF_REG, MEN_Z135_IER_MSIEN);
}
/**
* men_z135_start_tx() - Start transmitting characters
* @port: The UART port
*
* Start transmitting character. This actually doesn't transmit anything, but
* fires off the TX tasklet.
*/
static void men_z135_start_tx(struct uart_port *port)
{
struct men_z135_port *uart = to_men_z135(port);
if (uart->automode)
men_z135_disable_ms(port);
men_z135_handle_tx(uart);
}
/**
* men_z135_stop_rx() - Stop receiving characters
* @port: The UART port
*
* Stop receiving characters; the port is in the process of being closed.
*/
static void men_z135_stop_rx(struct uart_port *port)
{
struct men_z135_port *uart = to_men_z135(port);
men_z135_reg_clr(uart, MEN_Z135_CONF_REG, MEN_Z135_IER_RXCIEN);
}
/**
* men_z135_enable_ms() - Enable Modem Status
* @port: the port
*
* Enable Modem Status IRQ.
*/
static void men_z135_enable_ms(struct uart_port *port)
{
struct men_z135_port *uart = to_men_z135(port);
men_z135_reg_set(uart, MEN_Z135_CONF_REG, MEN_Z135_IER_MSIEN);
}
static int men_z135_startup(struct uart_port *port)
{
struct men_z135_port *uart = to_men_z135(port);
int err;
u32 conf_reg = 0;
err = men_z135_request_irq(uart);
if (err)
return -ENODEV;
conf_reg = ioread32(port->membase + MEN_Z135_CONF_REG);
/* Activate all but TX space available IRQ */
conf_reg |= MEN_Z135_ALL_IRQS & ~MEN_Z135_IER_TXCIEN;
conf_reg &= ~(0xff << 16);
conf_reg |= (txlvl << 16);
conf_reg |= (rxlvl << 20);
iowrite32(conf_reg, port->membase + MEN_Z135_CONF_REG);
if (rx_timeout)
iowrite32(rx_timeout, port->membase + MEN_Z135_TIMEOUT);
return 0;
}
static void men_z135_shutdown(struct uart_port *port)
{
struct men_z135_port *uart = to_men_z135(port);
u32 conf_reg = 0;
conf_reg |= MEN_Z135_ALL_IRQS;
men_z135_reg_clr(uart, MEN_Z135_CONF_REG, conf_reg);
free_irq(uart->port.irq, uart);
}
static void men_z135_set_termios(struct uart_port *port,
struct ktermios *termios,
const struct ktermios *old)
{
struct men_z135_port *uart = to_men_z135(port);
unsigned int baud;
u32 conf_reg;
u32 bd_reg;
u32 uart_freq;
u8 lcr;
conf_reg = ioread32(port->membase + MEN_Z135_CONF_REG);
lcr = LCR(conf_reg);
/* byte size */
switch (termios->c_cflag & CSIZE) {
case CS5:
lcr |= MEN_Z135_WL5;
break;
case CS6:
lcr |= MEN_Z135_WL6;
break;
case CS7:
lcr |= MEN_Z135_WL7;
break;
case CS8:
lcr |= MEN_Z135_WL8;
break;
}
/* stop bits */
if (termios->c_cflag & CSTOPB)
lcr |= MEN_Z135_NSTB2 << MEN_Z135_STB_SHIFT;
/* parity */
if (termios->c_cflag & PARENB) {
lcr |= MEN_Z135_PAR_ENA << MEN_Z135_PEN_SHIFT;
if (termios->c_cflag & PARODD)
lcr |= MEN_Z135_PTY_ODD << MEN_Z135_PTY_SHIFT;
else
lcr |= MEN_Z135_PTY_EVN << MEN_Z135_PTY_SHIFT;
} else
lcr |= MEN_Z135_PAR_DIS << MEN_Z135_PEN_SHIFT;
conf_reg |= MEN_Z135_IER_MSIEN;
if (termios->c_cflag & CRTSCTS) {
conf_reg |= MEN_Z135_MCR_RCFC;
uart->automode = true;
termios->c_cflag &= ~CLOCAL;
} else {
conf_reg &= ~MEN_Z135_MCR_RCFC;
uart->automode = false;
}
termios->c_cflag &= ~CMSPAR; /* Mark/Space parity is not supported */
conf_reg |= lcr << MEN_Z135_LCR_SHIFT;
iowrite32(conf_reg, port->membase + MEN_Z135_CONF_REG);
uart_freq = ioread32(port->membase + MEN_Z135_UART_FREQ);
if (uart_freq == 0)
uart_freq = MEN_Z135_BASECLK;
baud = uart_get_baud_rate(port, termios, old, 0, uart_freq / 16);
uart_port_lock_irq(port);
if (tty_termios_baud_rate(termios))
tty_termios_encode_baud_rate(termios, baud, baud);
bd_reg = uart_freq / (4 * baud);
iowrite32(bd_reg, port->membase + MEN_Z135_BAUD_REG);
uart_update_timeout(port, termios->c_cflag, baud);
uart_port_unlock_irq(port);
}
static const char *men_z135_type(struct uart_port *port)
{
return KBUILD_MODNAME;
}
static void men_z135_release_port(struct uart_port *port)
{
struct men_z135_port *uart = to_men_z135(port);
iounmap(port->membase);
port->membase = NULL;
mcb_release_mem(uart->mem);
}
static int men_z135_request_port(struct uart_port *port)
{
struct men_z135_port *uart = to_men_z135(port);
struct mcb_device *mdev = uart->mdev;
struct resource *mem;
mem = mcb_request_mem(uart->mdev, dev_name(&mdev->dev));
if (IS_ERR(mem))
return PTR_ERR(mem);
port->mapbase = mem->start;
uart->mem = mem;
port->membase = ioremap(mem->start, resource_size(mem));
if (port->membase == NULL) {
mcb_release_mem(mem);
return -ENOMEM;
}
return 0;
}
static void men_z135_config_port(struct uart_port *port, int type)
{
port->type = PORT_MEN_Z135;
men_z135_request_port(port);
}
static int men_z135_verify_port(struct uart_port *port,
struct serial_struct *serinfo)
{
return -EINVAL;
}
static const struct uart_ops men_z135_ops = {
.tx_empty = men_z135_tx_empty,
.set_mctrl = men_z135_set_mctrl,
.get_mctrl = men_z135_get_mctrl,
.stop_tx = men_z135_stop_tx,
.start_tx = men_z135_start_tx,
.stop_rx = men_z135_stop_rx,
.enable_ms = men_z135_enable_ms,
.startup = men_z135_startup,
.shutdown = men_z135_shutdown,
.set_termios = men_z135_set_termios,
.type = men_z135_type,
.release_port = men_z135_release_port,
.request_port = men_z135_request_port,
.config_port = men_z135_config_port,
.verify_port = men_z135_verify_port,
};
static struct uart_driver men_z135_driver = {
.owner = THIS_MODULE,
.driver_name = KBUILD_MODNAME,
.dev_name = "ttyHSU",
.major = 0,
.minor = 0,
.nr = MEN_Z135_MAX_PORTS,
};
/**
* men_z135_probe() - Probe a z135 instance
* @mdev: The MCB device
* @id: The MCB device ID
*
* men_z135_probe does the basic setup of hardware resources and registers the
* new uart port to the tty layer.
*/
static int men_z135_probe(struct mcb_device *mdev,
const struct mcb_device_id *id)
{
struct men_z135_port *uart;
struct resource *mem;
struct device *dev;
int err;
dev = &mdev->dev;
uart = devm_kzalloc(dev, sizeof(struct men_z135_port), GFP_KERNEL);
if (!uart)
return -ENOMEM;
uart->rxbuf = (unsigned char *)__get_free_page(GFP_KERNEL);
if (!uart->rxbuf)
return -ENOMEM;
mem = &mdev->mem;
mcb_set_drvdata(mdev, uart);
uart->port.uartclk = MEN_Z135_BASECLK * 16;
uart->port.fifosize = MEN_Z135_FIFO_SIZE;
uart->port.iotype = UPIO_MEM;
uart->port.ops = &men_z135_ops;
uart->port.irq = mcb_get_irq(mdev);
uart->port.flags = UPF_BOOT_AUTOCONF | UPF_IOREMAP;
uart->port.line = line++;
uart->port.dev = dev;
uart->port.type = PORT_MEN_Z135;
uart->port.mapbase = mem->start;
uart->port.membase = NULL;
uart->mdev = mdev;
spin_lock_init(&uart->lock);
err = uart_add_one_port(&men_z135_driver, &uart->port);
if (err)
goto err;
return 0;
err:
free_page((unsigned long) uart->rxbuf);
dev_err(dev, "Failed to add UART: %d\n", err);
return err;
}
/**
* men_z135_remove() - Remove a z135 instance from the system
*
* @mdev: The MCB device
*/
static void men_z135_remove(struct mcb_device *mdev)
{
struct men_z135_port *uart = mcb_get_drvdata(mdev);
line--;
uart_remove_one_port(&men_z135_driver, &uart->port);
free_page((unsigned long) uart->rxbuf);
}
static const struct mcb_device_id men_z135_ids[] = {
{ .device = 0x87 },
{ }
};
MODULE_DEVICE_TABLE(mcb, men_z135_ids);
static struct mcb_driver mcb_driver = {
.driver = {
.name = "z135-uart",
.owner = THIS_MODULE,
},
.probe = men_z135_probe,
.remove = men_z135_remove,
.id_table = men_z135_ids,
};
/**
* men_z135_init() - Driver Registration Routine
*
* men_z135_init is the first routine called when the driver is loaded. All it
* does is register with the legacy MEN Chameleon subsystem.
*/
static int __init men_z135_init(void)
{
int err;
err = uart_register_driver(&men_z135_driver);
if (err) {
pr_err("Failed to register UART: %d\n", err);
return err;
}
err = mcb_register_driver(&mcb_driver);
if (err) {
pr_err("Failed to register MCB driver: %d\n", err);
uart_unregister_driver(&men_z135_driver);
return err;
}
return 0;
}
module_init(men_z135_init);
/**
* men_z135_exit() - Driver Exit Routine
*
* men_z135_exit is called just before the driver is removed from memory.
*/
static void __exit men_z135_exit(void)
{
mcb_unregister_driver(&mcb_driver);
uart_unregister_driver(&men_z135_driver);
}
module_exit(men_z135_exit);
MODULE_AUTHOR("Johannes Thumshirn <[email protected]>");
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("MEN 16z135 High Speed UART");
MODULE_ALIAS("mcb:16z135");
MODULE_IMPORT_NS(MCB);
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