kernel-ark/drivers/serial/mpc52xx_uart.c
Kay Sievers e169c13964 serial: fix platform driver hotplug/coldplug
Since 43cc71eed1, the platform modalias is
prefixed with "platform:".  Add MODULE_ALIAS() to the hotpluggable serial
platform drivers, to re-enable auto loading.

NOTE that Kconfig for some of these drivers doesn't allow modular builds, and
thus doesn't match the driver source's unload support.  Presumably their
unload code is buggy and/or weakly tested...

[dbrownell@users.sourceforge.net: more drivers, registration fixes]
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Acked-by: Peter Korsgaard <jacmet@sunsite.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-15 19:35:40 -07:00

1466 lines
37 KiB
C

/*
* Driver for the PSC of the Freescale MPC52xx PSCs configured as UARTs.
*
* FIXME According to the usermanual the status bits in the status register
* are only updated when the peripherals access the FIFO and not when the
* CPU access them. So since we use this bits to know when we stop writing
* and reading, they may not be updated in-time and a race condition may
* exists. But I haven't be able to prove this and I don't care. But if
* any problem arises, it might worth checking. The TX/RX FIFO Stats
* registers should be used in addition.
* Update: Actually, they seem updated ... At least the bits we use.
*
*
* Maintainer : Sylvain Munaut <tnt@246tNt.com>
*
* Some of the code has been inspired/copied from the 2.4 code written
* by Dale Farnsworth <dfarnsworth@mvista.com>.
*
* Copyright (C) 2008 Freescale Semiconductor Inc.
* John Rigby <jrigby@gmail.com>
* Added support for MPC5121
* Copyright (C) 2006 Secret Lab Technologies Ltd.
* Grant Likely <grant.likely@secretlab.ca>
* Copyright (C) 2004-2006 Sylvain Munaut <tnt@246tNt.com>
* Copyright (C) 2003 MontaVista, Software, Inc.
*
* This file is licensed under the terms of the GNU General Public License
* version 2. This program is licensed "as is" without any warranty of any
* kind, whether express or implied.
*/
/* Platform device Usage :
*
* Since PSCs can have multiple function, the correct driver for each one
* is selected by calling mpc52xx_match_psc_function(...). The function
* handled by this driver is "uart".
*
* The driver init all necessary registers to place the PSC in uart mode without
* DCD. However, the pin multiplexing aren't changed and should be set either
* by the bootloader or in the platform init code.
*
* The idx field must be equal to the PSC index (e.g. 0 for PSC1, 1 for PSC2,
* and so on). So the PSC1 is mapped to /dev/ttyPSC0, PSC2 to /dev/ttyPSC1 and
* so on. But be warned, it's an ABSOLUTE REQUIREMENT ! This is needed mainly
* fpr the console code : without this 1:1 mapping, at early boot time, when we
* are parsing the kernel args console=ttyPSC?, we wouldn't know which PSC it
* will be mapped to.
*/
/* OF Platform device Usage :
*
* This driver is only used for PSCs configured in uart mode. The device
* tree will have a node for each PSC in uart mode w/ device_type = "serial"
* and "mpc52xx-psc-uart" in the compatible string
*
* By default, PSC devices are enumerated in the order they are found. However
* a particular PSC number can be forces by adding 'device_no = <port#>'
* to the device node.
*
* The driver init all necessary registers to place the PSC in uart mode without
* DCD. However, the pin multiplexing aren't changed and should be set either
* by the bootloader or in the platform init code.
*/
#undef DEBUG
#include <linux/device.h>
#include <linux/module.h>
#include <linux/tty.h>
#include <linux/serial.h>
#include <linux/sysrq.h>
#include <linux/console.h>
#include <linux/delay.h>
#include <linux/io.h>
#if defined(CONFIG_PPC_MERGE)
#include <linux/of.h>
#include <linux/of_platform.h>
#else
#include <linux/platform_device.h>
#endif
#include <asm/mpc52xx.h>
#include <asm/mpc512x.h>
#include <asm/mpc52xx_psc.h>
#if defined(CONFIG_SERIAL_MPC52xx_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
#define SUPPORT_SYSRQ
#endif
#include <linux/serial_core.h>
/* We've been assigned a range on the "Low-density serial ports" major */
#define SERIAL_PSC_MAJOR 204
#define SERIAL_PSC_MINOR 148
#define ISR_PASS_LIMIT 256 /* Max number of iteration in the interrupt */
static struct uart_port mpc52xx_uart_ports[MPC52xx_PSC_MAXNUM];
/* Rem: - We use the read_status_mask as a shadow of
* psc->mpc52xx_psc_imr
* - It's important that is array is all zero on start as we
* use it to know if it's initialized or not ! If it's not sure
* it's cleared, then a memset(...,0,...) should be added to
* the console_init
*/
#if defined(CONFIG_PPC_MERGE)
/* lookup table for matching device nodes to index numbers */
static struct device_node *mpc52xx_uart_nodes[MPC52xx_PSC_MAXNUM];
static void mpc52xx_uart_of_enumerate(void);
#endif
#define PSC(port) ((struct mpc52xx_psc __iomem *)((port)->membase))
/* Forward declaration of the interruption handling routine */
static irqreturn_t mpc52xx_uart_int(int irq, void *dev_id);
/* Simple macro to test if a port is console or not. This one is taken
* for serial_core.c and maybe should be moved to serial_core.h ? */
#ifdef CONFIG_SERIAL_CORE_CONSOLE
#define uart_console(port) \
((port)->cons && (port)->cons->index == (port)->line)
#else
#define uart_console(port) (0)
#endif
/* ======================================================================== */
/* PSC fifo operations for isolating differences between 52xx and 512x */
/* ======================================================================== */
struct psc_ops {
void (*fifo_init)(struct uart_port *port);
int (*raw_rx_rdy)(struct uart_port *port);
int (*raw_tx_rdy)(struct uart_port *port);
int (*rx_rdy)(struct uart_port *port);
int (*tx_rdy)(struct uart_port *port);
int (*tx_empty)(struct uart_port *port);
void (*stop_rx)(struct uart_port *port);
void (*start_tx)(struct uart_port *port);
void (*stop_tx)(struct uart_port *port);
void (*rx_clr_irq)(struct uart_port *port);
void (*tx_clr_irq)(struct uart_port *port);
void (*write_char)(struct uart_port *port, unsigned char c);
unsigned char (*read_char)(struct uart_port *port);
void (*cw_disable_ints)(struct uart_port *port);
void (*cw_restore_ints)(struct uart_port *port);
unsigned long (*getuartclk)(void *p);
};
#ifdef CONFIG_PPC_MPC52xx
#define FIFO_52xx(port) ((struct mpc52xx_psc_fifo __iomem *)(PSC(port)+1))
static void mpc52xx_psc_fifo_init(struct uart_port *port)
{
struct mpc52xx_psc __iomem *psc = PSC(port);
struct mpc52xx_psc_fifo __iomem *fifo = FIFO_52xx(port);
/* /32 prescaler */
out_be16(&psc->mpc52xx_psc_clock_select, 0xdd00);
out_8(&fifo->rfcntl, 0x00);
out_be16(&fifo->rfalarm, 0x1ff);
out_8(&fifo->tfcntl, 0x07);
out_be16(&fifo->tfalarm, 0x80);
port->read_status_mask |= MPC52xx_PSC_IMR_RXRDY | MPC52xx_PSC_IMR_TXRDY;
out_be16(&psc->mpc52xx_psc_imr, port->read_status_mask);
}
static int mpc52xx_psc_raw_rx_rdy(struct uart_port *port)
{
return in_be16(&PSC(port)->mpc52xx_psc_status)
& MPC52xx_PSC_SR_RXRDY;
}
static int mpc52xx_psc_raw_tx_rdy(struct uart_port *port)
{
return in_be16(&PSC(port)->mpc52xx_psc_status)
& MPC52xx_PSC_SR_TXRDY;
}
static int mpc52xx_psc_rx_rdy(struct uart_port *port)
{
return in_be16(&PSC(port)->mpc52xx_psc_isr)
& port->read_status_mask
& MPC52xx_PSC_IMR_RXRDY;
}
static int mpc52xx_psc_tx_rdy(struct uart_port *port)
{
return in_be16(&PSC(port)->mpc52xx_psc_isr)
& port->read_status_mask
& MPC52xx_PSC_IMR_TXRDY;
}
static int mpc52xx_psc_tx_empty(struct uart_port *port)
{
return in_be16(&PSC(port)->mpc52xx_psc_status)
& MPC52xx_PSC_SR_TXEMP;
}
static void mpc52xx_psc_start_tx(struct uart_port *port)
{
port->read_status_mask |= MPC52xx_PSC_IMR_TXRDY;
out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask);
}
static void mpc52xx_psc_stop_tx(struct uart_port *port)
{
port->read_status_mask &= ~MPC52xx_PSC_IMR_TXRDY;
out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask);
}
static void mpc52xx_psc_stop_rx(struct uart_port *port)
{
port->read_status_mask &= ~MPC52xx_PSC_IMR_RXRDY;
out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask);
}
static void mpc52xx_psc_rx_clr_irq(struct uart_port *port)
{
}
static void mpc52xx_psc_tx_clr_irq(struct uart_port *port)
{
}
static void mpc52xx_psc_write_char(struct uart_port *port, unsigned char c)
{
out_8(&PSC(port)->mpc52xx_psc_buffer_8, c);
}
static unsigned char mpc52xx_psc_read_char(struct uart_port *port)
{
return in_8(&PSC(port)->mpc52xx_psc_buffer_8);
}
static void mpc52xx_psc_cw_disable_ints(struct uart_port *port)
{
out_be16(&PSC(port)->mpc52xx_psc_imr, 0);
}
static void mpc52xx_psc_cw_restore_ints(struct uart_port *port)
{
out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask);
}
/* Search for bus-frequency property in this node or a parent */
static unsigned long mpc52xx_getuartclk(void *p)
{
#if defined(CONFIG_PPC_MERGE)
/*
* 5200 UARTs have a / 32 prescaler
* but the generic serial code assumes 16
* so return ipb freq / 2
*/
return mpc52xx_find_ipb_freq(p) / 2;
#else
pr_debug("unexpected call to mpc52xx_getuartclk with arch/ppc\n");
return NULL;
#endif
}
static struct psc_ops mpc52xx_psc_ops = {
.fifo_init = mpc52xx_psc_fifo_init,
.raw_rx_rdy = mpc52xx_psc_raw_rx_rdy,
.raw_tx_rdy = mpc52xx_psc_raw_tx_rdy,
.rx_rdy = mpc52xx_psc_rx_rdy,
.tx_rdy = mpc52xx_psc_tx_rdy,
.tx_empty = mpc52xx_psc_tx_empty,
.stop_rx = mpc52xx_psc_stop_rx,
.start_tx = mpc52xx_psc_start_tx,
.stop_tx = mpc52xx_psc_stop_tx,
.rx_clr_irq = mpc52xx_psc_rx_clr_irq,
.tx_clr_irq = mpc52xx_psc_tx_clr_irq,
.write_char = mpc52xx_psc_write_char,
.read_char = mpc52xx_psc_read_char,
.cw_disable_ints = mpc52xx_psc_cw_disable_ints,
.cw_restore_ints = mpc52xx_psc_cw_restore_ints,
.getuartclk = mpc52xx_getuartclk,
};
#endif /* CONFIG_MPC52xx */
#ifdef CONFIG_PPC_MPC512x
#define FIFO_512x(port) ((struct mpc512x_psc_fifo __iomem *)(PSC(port)+1))
static void mpc512x_psc_fifo_init(struct uart_port *port)
{
out_be32(&FIFO_512x(port)->txcmd, MPC512x_PSC_FIFO_RESET_SLICE);
out_be32(&FIFO_512x(port)->txcmd, MPC512x_PSC_FIFO_ENABLE_SLICE);
out_be32(&FIFO_512x(port)->txalarm, 1);
out_be32(&FIFO_512x(port)->tximr, 0);
out_be32(&FIFO_512x(port)->rxcmd, MPC512x_PSC_FIFO_RESET_SLICE);
out_be32(&FIFO_512x(port)->rxcmd, MPC512x_PSC_FIFO_ENABLE_SLICE);
out_be32(&FIFO_512x(port)->rxalarm, 1);
out_be32(&FIFO_512x(port)->rximr, 0);
out_be32(&FIFO_512x(port)->tximr, MPC512x_PSC_FIFO_ALARM);
out_be32(&FIFO_512x(port)->rximr, MPC512x_PSC_FIFO_ALARM);
}
static int mpc512x_psc_raw_rx_rdy(struct uart_port *port)
{
return !(in_be32(&FIFO_512x(port)->rxsr) & MPC512x_PSC_FIFO_EMPTY);
}
static int mpc512x_psc_raw_tx_rdy(struct uart_port *port)
{
return !(in_be32(&FIFO_512x(port)->txsr) & MPC512x_PSC_FIFO_FULL);
}
static int mpc512x_psc_rx_rdy(struct uart_port *port)
{
return in_be32(&FIFO_512x(port)->rxsr)
& in_be32(&FIFO_512x(port)->rximr)
& MPC512x_PSC_FIFO_ALARM;
}
static int mpc512x_psc_tx_rdy(struct uart_port *port)
{
return in_be32(&FIFO_512x(port)->txsr)
& in_be32(&FIFO_512x(port)->tximr)
& MPC512x_PSC_FIFO_ALARM;
}
static int mpc512x_psc_tx_empty(struct uart_port *port)
{
return in_be32(&FIFO_512x(port)->txsr)
& MPC512x_PSC_FIFO_EMPTY;
}
static void mpc512x_psc_stop_rx(struct uart_port *port)
{
unsigned long rx_fifo_imr;
rx_fifo_imr = in_be32(&FIFO_512x(port)->rximr);
rx_fifo_imr &= ~MPC512x_PSC_FIFO_ALARM;
out_be32(&FIFO_512x(port)->rximr, rx_fifo_imr);
}
static void mpc512x_psc_start_tx(struct uart_port *port)
{
unsigned long tx_fifo_imr;
tx_fifo_imr = in_be32(&FIFO_512x(port)->tximr);
tx_fifo_imr |= MPC512x_PSC_FIFO_ALARM;
out_be32(&FIFO_512x(port)->tximr, tx_fifo_imr);
}
static void mpc512x_psc_stop_tx(struct uart_port *port)
{
unsigned long tx_fifo_imr;
tx_fifo_imr = in_be32(&FIFO_512x(port)->tximr);
tx_fifo_imr &= ~MPC512x_PSC_FIFO_ALARM;
out_be32(&FIFO_512x(port)->tximr, tx_fifo_imr);
}
static void mpc512x_psc_rx_clr_irq(struct uart_port *port)
{
out_be32(&FIFO_512x(port)->rxisr, in_be32(&FIFO_512x(port)->rxisr));
}
static void mpc512x_psc_tx_clr_irq(struct uart_port *port)
{
out_be32(&FIFO_512x(port)->txisr, in_be32(&FIFO_512x(port)->txisr));
}
static void mpc512x_psc_write_char(struct uart_port *port, unsigned char c)
{
out_8(&FIFO_512x(port)->txdata_8, c);
}
static unsigned char mpc512x_psc_read_char(struct uart_port *port)
{
return in_8(&FIFO_512x(port)->rxdata_8);
}
static void mpc512x_psc_cw_disable_ints(struct uart_port *port)
{
port->read_status_mask =
in_be32(&FIFO_512x(port)->tximr) << 16 |
in_be32(&FIFO_512x(port)->rximr);
out_be32(&FIFO_512x(port)->tximr, 0);
out_be32(&FIFO_512x(port)->rximr, 0);
}
static void mpc512x_psc_cw_restore_ints(struct uart_port *port)
{
out_be32(&FIFO_512x(port)->tximr,
(port->read_status_mask >> 16) & 0x7f);
out_be32(&FIFO_512x(port)->rximr, port->read_status_mask & 0x7f);
}
static unsigned long mpc512x_getuartclk(void *p)
{
return mpc512x_find_ips_freq(p);
}
static struct psc_ops mpc512x_psc_ops = {
.fifo_init = mpc512x_psc_fifo_init,
.raw_rx_rdy = mpc512x_psc_raw_rx_rdy,
.raw_tx_rdy = mpc512x_psc_raw_tx_rdy,
.rx_rdy = mpc512x_psc_rx_rdy,
.tx_rdy = mpc512x_psc_tx_rdy,
.tx_empty = mpc512x_psc_tx_empty,
.stop_rx = mpc512x_psc_stop_rx,
.start_tx = mpc512x_psc_start_tx,
.stop_tx = mpc512x_psc_stop_tx,
.rx_clr_irq = mpc512x_psc_rx_clr_irq,
.tx_clr_irq = mpc512x_psc_tx_clr_irq,
.write_char = mpc512x_psc_write_char,
.read_char = mpc512x_psc_read_char,
.cw_disable_ints = mpc512x_psc_cw_disable_ints,
.cw_restore_ints = mpc512x_psc_cw_restore_ints,
.getuartclk = mpc512x_getuartclk,
};
#endif
static struct psc_ops *psc_ops;
/* ======================================================================== */
/* UART operations */
/* ======================================================================== */
static unsigned int
mpc52xx_uart_tx_empty(struct uart_port *port)
{
return psc_ops->tx_empty(port) ? TIOCSER_TEMT : 0;
}
static void
mpc52xx_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
{
/* Not implemented */
}
static unsigned int
mpc52xx_uart_get_mctrl(struct uart_port *port)
{
/* Not implemented */
return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
}
static void
mpc52xx_uart_stop_tx(struct uart_port *port)
{
/* port->lock taken by caller */
psc_ops->stop_tx(port);
}
static void
mpc52xx_uart_start_tx(struct uart_port *port)
{
/* port->lock taken by caller */
psc_ops->start_tx(port);
}
static void
mpc52xx_uart_send_xchar(struct uart_port *port, char ch)
{
unsigned long flags;
spin_lock_irqsave(&port->lock, flags);
port->x_char = ch;
if (ch) {
/* Make sure tx interrupts are on */
/* Truly necessary ??? They should be anyway */
psc_ops->start_tx(port);
}
spin_unlock_irqrestore(&port->lock, flags);
}
static void
mpc52xx_uart_stop_rx(struct uart_port *port)
{
/* port->lock taken by caller */
psc_ops->stop_rx(port);
}
static void
mpc52xx_uart_enable_ms(struct uart_port *port)
{
/* Not implemented */
}
static void
mpc52xx_uart_break_ctl(struct uart_port *port, int ctl)
{
unsigned long flags;
spin_lock_irqsave(&port->lock, flags);
if (ctl == -1)
out_8(&PSC(port)->command, MPC52xx_PSC_START_BRK);
else
out_8(&PSC(port)->command, MPC52xx_PSC_STOP_BRK);
spin_unlock_irqrestore(&port->lock, flags);
}
static int
mpc52xx_uart_startup(struct uart_port *port)
{
struct mpc52xx_psc __iomem *psc = PSC(port);
int ret;
/* Request IRQ */
ret = request_irq(port->irq, mpc52xx_uart_int,
IRQF_DISABLED | IRQF_SAMPLE_RANDOM | IRQF_SHARED,
"mpc52xx_psc_uart", port);
if (ret)
return ret;
/* Reset/activate the port, clear and enable interrupts */
out_8(&psc->command, MPC52xx_PSC_RST_RX);
out_8(&psc->command, MPC52xx_PSC_RST_TX);
out_be32(&psc->sicr, 0); /* UART mode DCD ignored */
psc_ops->fifo_init(port);
out_8(&psc->command, MPC52xx_PSC_TX_ENABLE);
out_8(&psc->command, MPC52xx_PSC_RX_ENABLE);
return 0;
}
static void
mpc52xx_uart_shutdown(struct uart_port *port)
{
struct mpc52xx_psc __iomem *psc = PSC(port);
/* Shut down the port. Leave TX active if on a console port */
out_8(&psc->command, MPC52xx_PSC_RST_RX);
if (!uart_console(port))
out_8(&psc->command, MPC52xx_PSC_RST_TX);
port->read_status_mask = 0;
out_be16(&psc->mpc52xx_psc_imr, port->read_status_mask);
/* Release interrupt */
free_irq(port->irq, port);
}
static void
mpc52xx_uart_set_termios(struct uart_port *port, struct ktermios *new,
struct ktermios *old)
{
struct mpc52xx_psc __iomem *psc = PSC(port);
unsigned long flags;
unsigned char mr1, mr2;
unsigned short ctr;
unsigned int j, baud, quot;
/* Prepare what we're gonna write */
mr1 = 0;
switch (new->c_cflag & CSIZE) {
case CS5: mr1 |= MPC52xx_PSC_MODE_5_BITS;
break;
case CS6: mr1 |= MPC52xx_PSC_MODE_6_BITS;
break;
case CS7: mr1 |= MPC52xx_PSC_MODE_7_BITS;
break;
case CS8:
default: mr1 |= MPC52xx_PSC_MODE_8_BITS;
}
if (new->c_cflag & PARENB) {
mr1 |= (new->c_cflag & PARODD) ?
MPC52xx_PSC_MODE_PARODD : MPC52xx_PSC_MODE_PAREVEN;
} else
mr1 |= MPC52xx_PSC_MODE_PARNONE;
mr2 = 0;
if (new->c_cflag & CSTOPB)
mr2 |= MPC52xx_PSC_MODE_TWO_STOP;
else
mr2 |= ((new->c_cflag & CSIZE) == CS5) ?
MPC52xx_PSC_MODE_ONE_STOP_5_BITS :
MPC52xx_PSC_MODE_ONE_STOP;
baud = uart_get_baud_rate(port, new, old, 0, port->uartclk/16);
quot = uart_get_divisor(port, baud);
ctr = quot & 0xffff;
/* Get the lock */
spin_lock_irqsave(&port->lock, flags);
/* Update the per-port timeout */
uart_update_timeout(port, new->c_cflag, baud);
/* Do our best to flush TX & RX, so we don't loose anything */
/* But we don't wait indefinitly ! */
j = 5000000; /* Maximum wait */
/* FIXME Can't receive chars since set_termios might be called at early
* boot for the console, all stuff is not yet ready to receive at that
* time and that just makes the kernel oops */
/* while (j-- && mpc52xx_uart_int_rx_chars(port)); */
while (!mpc52xx_uart_tx_empty(port) && --j)
udelay(1);
if (!j)
printk(KERN_ERR "mpc52xx_uart.c: "
"Unable to flush RX & TX fifos in-time in set_termios."
"Some chars may have been lost.\n");
/* Reset the TX & RX */
out_8(&psc->command, MPC52xx_PSC_RST_RX);
out_8(&psc->command, MPC52xx_PSC_RST_TX);
/* Send new mode settings */
out_8(&psc->command, MPC52xx_PSC_SEL_MODE_REG_1);
out_8(&psc->mode, mr1);
out_8(&psc->mode, mr2);
out_8(&psc->ctur, ctr >> 8);
out_8(&psc->ctlr, ctr & 0xff);
/* Reenable TX & RX */
out_8(&psc->command, MPC52xx_PSC_TX_ENABLE);
out_8(&psc->command, MPC52xx_PSC_RX_ENABLE);
/* We're all set, release the lock */
spin_unlock_irqrestore(&port->lock, flags);
}
static const char *
mpc52xx_uart_type(struct uart_port *port)
{
return port->type == PORT_MPC52xx ? "MPC52xx PSC" : NULL;
}
static void
mpc52xx_uart_release_port(struct uart_port *port)
{
/* remapped by us ? */
if (port->flags & UPF_IOREMAP) {
iounmap(port->membase);
port->membase = NULL;
}
release_mem_region(port->mapbase, sizeof(struct mpc52xx_psc));
}
static int
mpc52xx_uart_request_port(struct uart_port *port)
{
int err;
if (port->flags & UPF_IOREMAP) /* Need to remap ? */
port->membase = ioremap(port->mapbase,
sizeof(struct mpc52xx_psc));
if (!port->membase)
return -EINVAL;
err = request_mem_region(port->mapbase, sizeof(struct mpc52xx_psc),
"mpc52xx_psc_uart") != NULL ? 0 : -EBUSY;
if (err && (port->flags & UPF_IOREMAP)) {
iounmap(port->membase);
port->membase = NULL;
}
return err;
}
static void
mpc52xx_uart_config_port(struct uart_port *port, int flags)
{
if ((flags & UART_CONFIG_TYPE)
&& (mpc52xx_uart_request_port(port) == 0))
port->type = PORT_MPC52xx;
}
static int
mpc52xx_uart_verify_port(struct uart_port *port, struct serial_struct *ser)
{
if (ser->type != PORT_UNKNOWN && ser->type != PORT_MPC52xx)
return -EINVAL;
if ((ser->irq != port->irq) ||
(ser->io_type != SERIAL_IO_MEM) ||
(ser->baud_base != port->uartclk) ||
(ser->iomem_base != (void *)port->mapbase) ||
(ser->hub6 != 0))
return -EINVAL;
return 0;
}
static struct uart_ops mpc52xx_uart_ops = {
.tx_empty = mpc52xx_uart_tx_empty,
.set_mctrl = mpc52xx_uart_set_mctrl,
.get_mctrl = mpc52xx_uart_get_mctrl,
.stop_tx = mpc52xx_uart_stop_tx,
.start_tx = mpc52xx_uart_start_tx,
.send_xchar = mpc52xx_uart_send_xchar,
.stop_rx = mpc52xx_uart_stop_rx,
.enable_ms = mpc52xx_uart_enable_ms,
.break_ctl = mpc52xx_uart_break_ctl,
.startup = mpc52xx_uart_startup,
.shutdown = mpc52xx_uart_shutdown,
.set_termios = mpc52xx_uart_set_termios,
/* .pm = mpc52xx_uart_pm, Not supported yet */
/* .set_wake = mpc52xx_uart_set_wake, Not supported yet */
.type = mpc52xx_uart_type,
.release_port = mpc52xx_uart_release_port,
.request_port = mpc52xx_uart_request_port,
.config_port = mpc52xx_uart_config_port,
.verify_port = mpc52xx_uart_verify_port
};
/* ======================================================================== */
/* Interrupt handling */
/* ======================================================================== */
static inline int
mpc52xx_uart_int_rx_chars(struct uart_port *port)
{
struct tty_struct *tty = port->info->tty;
unsigned char ch, flag;
unsigned short status;
/* While we can read, do so ! */
while (psc_ops->raw_rx_rdy(port)) {
/* Get the char */
ch = psc_ops->read_char(port);
/* Handle sysreq char */
#ifdef SUPPORT_SYSRQ
if (uart_handle_sysrq_char(port, ch)) {
port->sysrq = 0;
continue;
}
#endif
/* Store it */
flag = TTY_NORMAL;
port->icount.rx++;
status = in_be16(&PSC(port)->mpc52xx_psc_status);
if (status & (MPC52xx_PSC_SR_PE |
MPC52xx_PSC_SR_FE |
MPC52xx_PSC_SR_RB)) {
if (status & MPC52xx_PSC_SR_RB) {
flag = TTY_BREAK;
uart_handle_break(port);
} else if (status & MPC52xx_PSC_SR_PE)
flag = TTY_PARITY;
else if (status & MPC52xx_PSC_SR_FE)
flag = TTY_FRAME;
/* Clear error condition */
out_8(&PSC(port)->command, MPC52xx_PSC_RST_ERR_STAT);
}
tty_insert_flip_char(tty, ch, flag);
if (status & MPC52xx_PSC_SR_OE) {
/*
* Overrun is special, since it's
* reported immediately, and doesn't
* affect the current character
*/
tty_insert_flip_char(tty, 0, TTY_OVERRUN);
}
}
tty_flip_buffer_push(tty);
return psc_ops->raw_rx_rdy(port);
}
static inline int
mpc52xx_uart_int_tx_chars(struct uart_port *port)
{
struct circ_buf *xmit = &port->info->xmit;
/* Process out of band chars */
if (port->x_char) {
psc_ops->write_char(port, port->x_char);
port->icount.tx++;
port->x_char = 0;
return 1;
}
/* Nothing to do ? */
if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
mpc52xx_uart_stop_tx(port);
return 0;
}
/* Send chars */
while (psc_ops->raw_tx_rdy(port)) {
psc_ops->write_char(port, xmit->buf[xmit->tail]);
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
port->icount.tx++;
if (uart_circ_empty(xmit))
break;
}
/* Wake up */
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(port);
/* Maybe we're done after all */
if (uart_circ_empty(xmit)) {
mpc52xx_uart_stop_tx(port);
return 0;
}
return 1;
}
static irqreturn_t
mpc52xx_uart_int(int irq, void *dev_id)
{
struct uart_port *port = dev_id;
unsigned long pass = ISR_PASS_LIMIT;
unsigned int keepgoing;
spin_lock(&port->lock);
/* While we have stuff to do, we continue */
do {
/* If we don't find anything to do, we stop */
keepgoing = 0;
psc_ops->rx_clr_irq(port);
if (psc_ops->rx_rdy(port))
keepgoing |= mpc52xx_uart_int_rx_chars(port);
psc_ops->tx_clr_irq(port);
if (psc_ops->tx_rdy(port))
keepgoing |= mpc52xx_uart_int_tx_chars(port);
/* Limit number of iteration */
if (!(--pass))
keepgoing = 0;
} while (keepgoing);
spin_unlock(&port->lock);
return IRQ_HANDLED;
}
/* ======================================================================== */
/* Console ( if applicable ) */
/* ======================================================================== */
#ifdef CONFIG_SERIAL_MPC52xx_CONSOLE
static void __init
mpc52xx_console_get_options(struct uart_port *port,
int *baud, int *parity, int *bits, int *flow)
{
struct mpc52xx_psc __iomem *psc = PSC(port);
unsigned char mr1;
pr_debug("mpc52xx_console_get_options(port=%p)\n", port);
/* Read the mode registers */
out_8(&psc->command, MPC52xx_PSC_SEL_MODE_REG_1);
mr1 = in_8(&psc->mode);
/* CT{U,L}R are write-only ! */
*baud = CONFIG_SERIAL_MPC52xx_CONSOLE_BAUD;
#if !defined(CONFIG_PPC_MERGE)
if (__res.bi_baudrate)
*baud = __res.bi_baudrate;
#endif
/* Parse them */
switch (mr1 & MPC52xx_PSC_MODE_BITS_MASK) {
case MPC52xx_PSC_MODE_5_BITS:
*bits = 5;
break;
case MPC52xx_PSC_MODE_6_BITS:
*bits = 6;
break;
case MPC52xx_PSC_MODE_7_BITS:
*bits = 7;
break;
case MPC52xx_PSC_MODE_8_BITS:
default:
*bits = 8;
}
if (mr1 & MPC52xx_PSC_MODE_PARNONE)
*parity = 'n';
else
*parity = mr1 & MPC52xx_PSC_MODE_PARODD ? 'o' : 'e';
}
static void
mpc52xx_console_write(struct console *co, const char *s, unsigned int count)
{
struct uart_port *port = &mpc52xx_uart_ports[co->index];
unsigned int i, j;
/* Disable interrupts */
psc_ops->cw_disable_ints(port);
/* Wait the TX buffer to be empty */
j = 5000000; /* Maximum wait */
while (!mpc52xx_uart_tx_empty(port) && --j)
udelay(1);
/* Write all the chars */
for (i = 0; i < count; i++, s++) {
/* Line return handling */
if (*s == '\n')
psc_ops->write_char(port, '\r');
/* Send the char */
psc_ops->write_char(port, *s);
/* Wait the TX buffer to be empty */
j = 20000; /* Maximum wait */
while (!mpc52xx_uart_tx_empty(port) && --j)
udelay(1);
}
/* Restore interrupt state */
psc_ops->cw_restore_ints(port);
}
#if !defined(CONFIG_PPC_MERGE)
static int __init
mpc52xx_console_setup(struct console *co, char *options)
{
struct uart_port *port = &mpc52xx_uart_ports[co->index];
int baud = CONFIG_SERIAL_MPC52xx_CONSOLE_BAUD;
int bits = 8;
int parity = 'n';
int flow = 'n';
if (co->index < 0 || co->index >= MPC52xx_PSC_MAXNUM)
return -EINVAL;
/* Basic port init. Needed since we use some uart_??? func before
* real init for early access */
spin_lock_init(&port->lock);
port->uartclk = __res.bi_ipbfreq / 2; /* Look at CTLR doc */
port->ops = &mpc52xx_uart_ops;
port->mapbase = MPC52xx_PA(MPC52xx_PSCx_OFFSET(co->index+1));
/* We ioremap ourself */
port->membase = ioremap(port->mapbase, MPC52xx_PSC_SIZE);
if (port->membase == NULL)
return -EINVAL;
/* Setup the port parameters accoding to options */
if (options)
uart_parse_options(options, &baud, &parity, &bits, &flow);
else
mpc52xx_console_get_options(port, &baud, &parity, &bits, &flow);
return uart_set_options(port, co, baud, parity, bits, flow);
}
#else
static int __init
mpc52xx_console_setup(struct console *co, char *options)
{
struct uart_port *port = &mpc52xx_uart_ports[co->index];
struct device_node *np = mpc52xx_uart_nodes[co->index];
unsigned int uartclk;
struct resource res;
int ret;
int baud = CONFIG_SERIAL_MPC52xx_CONSOLE_BAUD;
int bits = 8;
int parity = 'n';
int flow = 'n';
pr_debug("mpc52xx_console_setup co=%p, co->index=%i, options=%s\n",
co, co->index, options);
if ((co->index < 0) || (co->index > MPC52xx_PSC_MAXNUM)) {
pr_debug("PSC%x out of range\n", co->index);
return -EINVAL;
}
if (!np) {
pr_debug("PSC%x not found in device tree\n", co->index);
return -EINVAL;
}
pr_debug("Console on ttyPSC%x is %s\n",
co->index, mpc52xx_uart_nodes[co->index]->full_name);
/* Fetch register locations */
ret = of_address_to_resource(np, 0, &res);
if (ret) {
pr_debug("Could not get resources for PSC%x\n", co->index);
return ret;
}
uartclk = psc_ops->getuartclk(np);
if (uartclk == 0) {
pr_debug("Could not find uart clock frequency!\n");
return -EINVAL;
}
/* Basic port init. Needed since we use some uart_??? func before
* real init for early access */
spin_lock_init(&port->lock);
port->uartclk = uartclk;
port->ops = &mpc52xx_uart_ops;
port->mapbase = res.start;
port->membase = ioremap(res.start, sizeof(struct mpc52xx_psc));
port->irq = irq_of_parse_and_map(np, 0);
if (port->membase == NULL)
return -EINVAL;
pr_debug("mpc52xx-psc uart at %p, mapped to %p, irq=%x, freq=%i\n",
(void *)port->mapbase, port->membase,
port->irq, port->uartclk);
/* Setup the port parameters accoding to options */
if (options)
uart_parse_options(options, &baud, &parity, &bits, &flow);
else
mpc52xx_console_get_options(port, &baud, &parity, &bits, &flow);
pr_debug("Setting console parameters: %i %i%c1 flow=%c\n",
baud, bits, parity, flow);
return uart_set_options(port, co, baud, parity, bits, flow);
}
#endif /* defined(CONFIG_PPC_MERGE) */
static struct uart_driver mpc52xx_uart_driver;
static struct console mpc52xx_console = {
.name = "ttyPSC",
.write = mpc52xx_console_write,
.device = uart_console_device,
.setup = mpc52xx_console_setup,
.flags = CON_PRINTBUFFER,
.index = -1, /* Specified on the cmdline (e.g. console=ttyPSC0) */
.data = &mpc52xx_uart_driver,
};
static int __init
mpc52xx_console_init(void)
{
#if defined(CONFIG_PPC_MERGE)
mpc52xx_uart_of_enumerate();
#endif
register_console(&mpc52xx_console);
return 0;
}
console_initcall(mpc52xx_console_init);
#define MPC52xx_PSC_CONSOLE &mpc52xx_console
#else
#define MPC52xx_PSC_CONSOLE NULL
#endif
/* ======================================================================== */
/* UART Driver */
/* ======================================================================== */
static struct uart_driver mpc52xx_uart_driver = {
.driver_name = "mpc52xx_psc_uart",
.dev_name = "ttyPSC",
.major = SERIAL_PSC_MAJOR,
.minor = SERIAL_PSC_MINOR,
.nr = MPC52xx_PSC_MAXNUM,
.cons = MPC52xx_PSC_CONSOLE,
};
#if !defined(CONFIG_PPC_MERGE)
/* ======================================================================== */
/* Platform Driver */
/* ======================================================================== */
static int __devinit
mpc52xx_uart_probe(struct platform_device *dev)
{
struct resource *res = dev->resource;
struct uart_port *port = NULL;
int i, idx, ret;
/* Check validity & presence */
idx = dev->id;
if (idx < 0 || idx >= MPC52xx_PSC_MAXNUM)
return -EINVAL;
if (!mpc52xx_match_psc_function(idx, "uart"))
return -ENODEV;
/* Init the port structure */
port = &mpc52xx_uart_ports[idx];
spin_lock_init(&port->lock);
port->uartclk = __res.bi_ipbfreq / 2; /* Look at CTLR doc */
port->fifosize = 512;
port->iotype = UPIO_MEM;
port->flags = UPF_BOOT_AUTOCONF |
(uart_console(port) ? 0 : UPF_IOREMAP);
port->line = idx;
port->ops = &mpc52xx_uart_ops;
port->dev = &dev->dev;
/* Search for IRQ and mapbase */
for (i = 0 ; i < dev->num_resources ; i++, res++) {
if (res->flags & IORESOURCE_MEM)
port->mapbase = res->start;
else if (res->flags & IORESOURCE_IRQ)
port->irq = res->start;
}
if (!port->irq || !port->mapbase)
return -EINVAL;
/* Add the port to the uart sub-system */
ret = uart_add_one_port(&mpc52xx_uart_driver, port);
if (!ret)
platform_set_drvdata(dev, (void *)port);
return ret;
}
static int
mpc52xx_uart_remove(struct platform_device *dev)
{
struct uart_port *port = (struct uart_port *) platform_get_drvdata(dev);
platform_set_drvdata(dev, NULL);
if (port)
uart_remove_one_port(&mpc52xx_uart_driver, port);
return 0;
}
#ifdef CONFIG_PM
static int
mpc52xx_uart_suspend(struct platform_device *dev, pm_message_t state)
{
struct uart_port *port = (struct uart_port *) platform_get_drvdata(dev);
if (port)
uart_suspend_port(&mpc52xx_uart_driver, port);
return 0;
}
static int
mpc52xx_uart_resume(struct platform_device *dev)
{
struct uart_port *port = (struct uart_port *) platform_get_drvdata(dev);
if (port)
uart_resume_port(&mpc52xx_uart_driver, port);
return 0;
}
#endif
/* work with hotplug and coldplug */
MODULE_ALIAS("platform:mpc52xx-psc");
static struct platform_driver mpc52xx_uart_platform_driver = {
.probe = mpc52xx_uart_probe,
.remove = mpc52xx_uart_remove,
#ifdef CONFIG_PM
.suspend = mpc52xx_uart_suspend,
.resume = mpc52xx_uart_resume,
#endif
.driver = {
.owner = THIS_MODULE,
.name = "mpc52xx-psc",
},
};
#endif /* !defined(CONFIG_PPC_MERGE) */
#if defined(CONFIG_PPC_MERGE)
/* ======================================================================== */
/* OF Platform Driver */
/* ======================================================================== */
static struct of_device_id mpc52xx_uart_of_match[] = {
#ifdef CONFIG_PPC_MPC52xx
{ .compatible = "fsl,mpc5200-psc-uart", .data = &mpc52xx_psc_ops, },
/* binding used by old lite5200 device trees: */
{ .compatible = "mpc5200-psc-uart", .data = &mpc52xx_psc_ops, },
/* binding used by efika: */
{ .compatible = "mpc5200-serial", .data = &mpc52xx_psc_ops, },
#endif
#ifdef CONFIG_PPC_MPC512x
{ .compatible = "fsl,mpc5121-psc-uart", .data = &mpc512x_psc_ops, },
{},
#endif
};
static int __devinit
mpc52xx_uart_of_probe(struct of_device *op, const struct of_device_id *match)
{
int idx = -1;
unsigned int uartclk;
struct uart_port *port = NULL;
struct resource res;
int ret;
dev_dbg(&op->dev, "mpc52xx_uart_probe(op=%p, match=%p)\n", op, match);
/* Check validity & presence */
for (idx = 0; idx < MPC52xx_PSC_MAXNUM; idx++)
if (mpc52xx_uart_nodes[idx] == op->node)
break;
if (idx >= MPC52xx_PSC_MAXNUM)
return -EINVAL;
pr_debug("Found %s assigned to ttyPSC%x\n",
mpc52xx_uart_nodes[idx]->full_name, idx);
uartclk = psc_ops->getuartclk(op->node);
if (uartclk == 0) {
dev_dbg(&op->dev, "Could not find uart clock frequency!\n");
return -EINVAL;
}
/* Init the port structure */
port = &mpc52xx_uart_ports[idx];
spin_lock_init(&port->lock);
port->uartclk = uartclk;
port->fifosize = 512;
port->iotype = UPIO_MEM;
port->flags = UPF_BOOT_AUTOCONF |
(uart_console(port) ? 0 : UPF_IOREMAP);
port->line = idx;
port->ops = &mpc52xx_uart_ops;
port->dev = &op->dev;
/* Search for IRQ and mapbase */
ret = of_address_to_resource(op->node, 0, &res);
if (ret)
return ret;
port->mapbase = res.start;
port->irq = irq_of_parse_and_map(op->node, 0);
dev_dbg(&op->dev, "mpc52xx-psc uart at %p, irq=%x, freq=%i\n",
(void *)port->mapbase, port->irq, port->uartclk);
if ((port->irq == NO_IRQ) || !port->mapbase) {
printk(KERN_ERR "Could not allocate resources for PSC\n");
return -EINVAL;
}
/* Add the port to the uart sub-system */
ret = uart_add_one_port(&mpc52xx_uart_driver, port);
if (!ret)
dev_set_drvdata(&op->dev, (void *)port);
return ret;
}
static int
mpc52xx_uart_of_remove(struct of_device *op)
{
struct uart_port *port = dev_get_drvdata(&op->dev);
dev_set_drvdata(&op->dev, NULL);
if (port) {
uart_remove_one_port(&mpc52xx_uart_driver, port);
irq_dispose_mapping(port->irq);
}
return 0;
}
#ifdef CONFIG_PM
static int
mpc52xx_uart_of_suspend(struct of_device *op, pm_message_t state)
{
struct uart_port *port = (struct uart_port *) dev_get_drvdata(&op->dev);
if (port)
uart_suspend_port(&mpc52xx_uart_driver, port);
return 0;
}
static int
mpc52xx_uart_of_resume(struct of_device *op)
{
struct uart_port *port = (struct uart_port *) dev_get_drvdata(&op->dev);
if (port)
uart_resume_port(&mpc52xx_uart_driver, port);
return 0;
}
#endif
static void
mpc52xx_uart_of_assign(struct device_node *np, int idx)
{
int free_idx = -1;
int i;
/* Find the first free node */
for (i = 0; i < MPC52xx_PSC_MAXNUM; i++) {
if (mpc52xx_uart_nodes[i] == NULL) {
free_idx = i;
break;
}
}
if ((idx < 0) || (idx >= MPC52xx_PSC_MAXNUM))
idx = free_idx;
if (idx < 0)
return; /* No free slot; abort */
of_node_get(np);
/* If the slot is already occupied, then swap slots */
if (mpc52xx_uart_nodes[idx] && (free_idx != -1))
mpc52xx_uart_nodes[free_idx] = mpc52xx_uart_nodes[idx];
mpc52xx_uart_nodes[idx] = np;
}
static void
mpc52xx_uart_of_enumerate(void)
{
static int enum_done;
struct device_node *np;
const unsigned int *devno;
const struct of_device_id *match;
int i;
if (enum_done)
return;
for_each_node_by_type(np, "serial") {
match = of_match_node(mpc52xx_uart_of_match, np);
if (!match)
continue;
psc_ops = match->data;
/* Is a particular device number requested? */
devno = of_get_property(np, "port-number", NULL);
mpc52xx_uart_of_assign(np, devno ? *devno : -1);
}
enum_done = 1;
for (i = 0; i < MPC52xx_PSC_MAXNUM; i++) {
if (mpc52xx_uart_nodes[i])
pr_debug("%s assigned to ttyPSC%x\n",
mpc52xx_uart_nodes[i]->full_name, i);
}
}
MODULE_DEVICE_TABLE(of, mpc52xx_uart_of_match);
static struct of_platform_driver mpc52xx_uart_of_driver = {
.match_table = mpc52xx_uart_of_match,
.probe = mpc52xx_uart_of_probe,
.remove = mpc52xx_uart_of_remove,
#ifdef CONFIG_PM
.suspend = mpc52xx_uart_of_suspend,
.resume = mpc52xx_uart_of_resume,
#endif
.driver = {
.name = "mpc52xx-psc-uart",
},
};
#endif /* defined(CONFIG_PPC_MERGE) */
/* ======================================================================== */
/* Module */
/* ======================================================================== */
static int __init
mpc52xx_uart_init(void)
{
int ret;
printk(KERN_INFO "Serial: MPC52xx PSC UART driver\n");
ret = uart_register_driver(&mpc52xx_uart_driver);
if (ret) {
printk(KERN_ERR "%s: uart_register_driver failed (%i)\n",
__FILE__, ret);
return ret;
}
#if defined(CONFIG_PPC_MERGE)
mpc52xx_uart_of_enumerate();
ret = of_register_platform_driver(&mpc52xx_uart_of_driver);
if (ret) {
printk(KERN_ERR "%s: of_register_platform_driver failed (%i)\n",
__FILE__, ret);
uart_unregister_driver(&mpc52xx_uart_driver);
return ret;
}
#else
psc_ops = &mpc52xx_psc_ops;
ret = platform_driver_register(&mpc52xx_uart_platform_driver);
if (ret) {
printk(KERN_ERR "%s: platform_driver_register failed (%i)\n",
__FILE__, ret);
uart_unregister_driver(&mpc52xx_uart_driver);
return ret;
}
#endif
return 0;
}
static void __exit
mpc52xx_uart_exit(void)
{
#if defined(CONFIG_PPC_MERGE)
of_unregister_platform_driver(&mpc52xx_uart_of_driver);
#else
platform_driver_unregister(&mpc52xx_uart_platform_driver);
#endif
uart_unregister_driver(&mpc52xx_uart_driver);
}
module_init(mpc52xx_uart_init);
module_exit(mpc52xx_uart_exit);
MODULE_AUTHOR("Sylvain Munaut <tnt@246tNt.com>");
MODULE_DESCRIPTION("Freescale MPC52xx PSC UART");
MODULE_LICENSE("GPL");