linux/drivers/tty/serial/zs.c

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tty: add SPDX identifiers to all remaining files in drivers/tty/ It's good to have SPDX identifiers in all files to make it easier to audit the kernel tree for correct licenses. Update the drivers/tty files files with the correct SPDX license identifier based on the license text in the file itself. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This work is based on a script and data from Thomas Gleixner, Philippe Ombredanne, and Kate Stewart. Cc: Jiri Slaby <jslaby@suse.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Chris Metcalf <cmetcalf@mellanox.com> Cc: Jiri Kosina <jikos@kernel.org> Cc: David Sterba <dsterba@suse.com> Cc: James Hogan <jhogan@kernel.org> Cc: Rob Herring <robh@kernel.org> Cc: Eric Anholt <eric@anholt.net> Cc: Stefan Wahren <stefan.wahren@i2se.com> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: Ray Jui <rjui@broadcom.com> Cc: Scott Branden <sbranden@broadcom.com> Cc: bcm-kernel-feedback-list@broadcom.com Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Helge Deller <deller@gmx.de> Cc: Joachim Eastwood <manabian@gmail.com> Cc: Matthias Brugger <matthias.bgg@gmail.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Tobias Klauser <tklauser@distanz.ch> Cc: Russell King <linux@armlinux.org.uk> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Richard Genoud <richard.genoud@gmail.com> Cc: Alexander Shiyan <shc_work@mail.ru> Cc: Baruch Siach <baruch@tkos.co.il> Cc: "Maciej W. Rozycki" <macro@linux-mips.org> Cc: "Uwe Kleine-König" <kernel@pengutronix.de> Cc: Pat Gefre <pfg@sgi.com> Cc: "Guilherme G. Piccoli" <gpiccoli@linux.vnet.ibm.com> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Vladimir Zapolskiy <vz@mleia.com> Cc: Sylvain Lemieux <slemieux.tyco@gmail.com> Cc: Carlo Caione <carlo@caione.org> Cc: Kevin Hilman <khilman@baylibre.com> Cc: Liviu Dudau <liviu.dudau@arm.com> Cc: Sudeep Holla <sudeep.holla@arm.com> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: Andy Gross <andy.gross@linaro.org> Cc: David Brown <david.brown@linaro.org> Cc: "Andreas Färber" <afaerber@suse.de> Cc: Kevin Cernekee <cernekee@gmail.com> Cc: Laxman Dewangan <ldewangan@nvidia.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Jonathan Hunter <jonathanh@nvidia.com> Cc: Barry Song <baohua@kernel.org> Cc: Patrice Chotard <patrice.chotard@st.com> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> Cc: Alexandre Torgue <alexandre.torgue@st.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Peter Korsgaard <jacmet@sunsite.dk> Cc: Timur Tabi <timur@tabi.org> Cc: Tony Prisk <linux@prisktech.co.nz> Cc: Michal Simek <michal.simek@xilinx.com> Cc: "Sören Brinkmann" <soren.brinkmann@xilinx.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Kate Stewart <kstewart@linuxfoundation.org> Cc: Philippe Ombredanne <pombredanne@nexb.com> Cc: Jiri Slaby <jslaby@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-06 17:11:51 +00:00
// SPDX-License-Identifier: GPL-2.0
/*
* zs.c: Serial port driver for IOASIC DECstations.
*
* Derived from drivers/sbus/char/sunserial.c by Paul Mackerras.
* Derived from drivers/macintosh/macserial.c by Harald Koerfgen.
*
* DECstation changes
* Copyright (C) 1998-2000 Harald Koerfgen
* Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2007 Maciej W. Rozycki
*
* For the rest of the code the original Copyright applies:
* Copyright (C) 1996 Paul Mackerras (Paul.Mackerras@cs.anu.edu.au)
* Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
*
*
* Note: for IOASIC systems the wiring is as follows:
*
* mouse/keyboard:
* DIN-7 MJ-4 signal SCC
* 2 1 TxD <- A.TxD
* 3 4 RxD -> A.RxD
*
* EIA-232/EIA-423:
* DB-25 MMJ-6 signal SCC
* 2 2 TxD <- B.TxD
* 3 5 RxD -> B.RxD
* 4 RTS <- ~A.RTS
* 5 CTS -> ~B.CTS
* 6 6 DSR -> ~A.SYNC
* 8 CD -> ~B.DCD
* 12 DSRS(DCE) -> ~A.CTS (*)
* 15 TxC -> B.TxC
* 17 RxC -> B.RxC
* 20 1 DTR <- ~A.DTR
* 22 RI -> ~A.DCD
* 23 DSRS(DTE) <- ~B.RTS
*
* (*) EIA-232 defines the signal at this pin to be SCD, while DSRS(DCE)
* is shared with DSRS(DTE) at pin 23.
*
* As you can immediately notice the wiring of the RTS, DTR and DSR signals
* is a bit odd. This makes the handling of port B unnecessarily
* complicated and prevents the use of some automatic modes of operation.
*/
#if defined(CONFIG_SERIAL_ZS_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
#define SUPPORT_SYSRQ
#endif
#include <linux/bug.h>
#include <linux/console.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/irqflags.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/major.h>
#include <linux/serial.h>
#include <linux/serial_core.h>
#include <linux/spinlock.h>
#include <linux/sysrq.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/types.h>
#include <linux/atomic.h>
#include <asm/dec/interrupts.h>
#include <asm/dec/ioasic_addrs.h>
#include <asm/dec/system.h>
#include "zs.h"
MODULE_AUTHOR("Maciej W. Rozycki <macro@linux-mips.org>");
MODULE_DESCRIPTION("DECstation Z85C30 serial driver");
MODULE_LICENSE("GPL");
static char zs_name[] __initdata = "DECstation Z85C30 serial driver version ";
static char zs_version[] __initdata = "0.10";
/*
* It would be nice to dynamically allocate everything that
* depends on ZS_NUM_SCCS, so we could support any number of
* Z85C30s, but for now...
*/
#define ZS_NUM_SCCS 2 /* Max # of ZS chips supported. */
#define ZS_NUM_CHAN 2 /* 2 channels per chip. */
#define ZS_CHAN_A 0 /* Index of the channel A. */
#define ZS_CHAN_B 1 /* Index of the channel B. */
#define ZS_CHAN_IO_SIZE 8 /* IOMEM space size. */
#define ZS_CHAN_IO_STRIDE 4 /* Register alignment. */
#define ZS_CHAN_IO_OFFSET 1 /* The SCC resides on the high byte
of the 16-bit IOBUS. */
#define ZS_CLOCK 7372800 /* Z85C30 PCLK input clock rate. */
#define to_zport(uport) container_of(uport, struct zs_port, port)
struct zs_parms {
resource_size_t scc[ZS_NUM_SCCS];
int irq[ZS_NUM_SCCS];
};
static struct zs_scc zs_sccs[ZS_NUM_SCCS];
static u8 zs_init_regs[ZS_NUM_REGS] __initdata = {
0, /* write 0 */
PAR_SPEC, /* write 1 */
0, /* write 2 */
0, /* write 3 */
X16CLK | SB1, /* write 4 */
0, /* write 5 */
0, 0, 0, /* write 6, 7, 8 */
MIE | DLC | NV, /* write 9 */
NRZ, /* write 10 */
TCBR | RCBR, /* write 11 */
0, 0, /* BRG time constant, write 12 + 13 */
BRSRC | BRENABL, /* write 14 */
0, /* write 15 */
};
/*
* Debugging.
*/
#undef ZS_DEBUG_REGS
/*
* Reading and writing Z85C30 registers.
*/
static void recovery_delay(void)
{
udelay(2);
}
static u8 read_zsreg(struct zs_port *zport, int reg)
{
void __iomem *control = zport->port.membase + ZS_CHAN_IO_OFFSET;
u8 retval;
if (reg != 0) {
writeb(reg & 0xf, control);
fast_iob();
recovery_delay();
}
retval = readb(control);
recovery_delay();
return retval;
}
static void write_zsreg(struct zs_port *zport, int reg, u8 value)
{
void __iomem *control = zport->port.membase + ZS_CHAN_IO_OFFSET;
if (reg != 0) {
writeb(reg & 0xf, control);
fast_iob(); recovery_delay();
}
writeb(value, control);
fast_iob();
recovery_delay();
return;
}
static u8 read_zsdata(struct zs_port *zport)
{
void __iomem *data = zport->port.membase +
ZS_CHAN_IO_STRIDE + ZS_CHAN_IO_OFFSET;
u8 retval;
retval = readb(data);
recovery_delay();
return retval;
}
static void write_zsdata(struct zs_port *zport, u8 value)
{
void __iomem *data = zport->port.membase +
ZS_CHAN_IO_STRIDE + ZS_CHAN_IO_OFFSET;
writeb(value, data);
fast_iob();
recovery_delay();
return;
}
#ifdef ZS_DEBUG_REGS
void zs_dump(void)
{
struct zs_port *zport;
int i, j;
for (i = 0; i < ZS_NUM_SCCS * ZS_NUM_CHAN; i++) {
zport = &zs_sccs[i / ZS_NUM_CHAN].zport[i % ZS_NUM_CHAN];
if (!zport->scc)
continue;
for (j = 0; j < 16; j++)
printk("W%-2d = 0x%02x\t", j, zport->regs[j]);
printk("\n");
for (j = 0; j < 16; j++)
printk("R%-2d = 0x%02x\t", j, read_zsreg(zport, j));
printk("\n\n");
}
}
#endif
static void zs_spin_lock_cond_irq(spinlock_t *lock, int irq)
{
if (irq)
spin_lock_irq(lock);
else
spin_lock(lock);
}
static void zs_spin_unlock_cond_irq(spinlock_t *lock, int irq)
{
if (irq)
spin_unlock_irq(lock);
else
spin_unlock(lock);
}
static int zs_receive_drain(struct zs_port *zport)
{
int loops = 10000;
while ((read_zsreg(zport, R0) & Rx_CH_AV) && --loops)
read_zsdata(zport);
return loops;
}
static int zs_transmit_drain(struct zs_port *zport, int irq)
{
struct zs_scc *scc = zport->scc;
int loops = 10000;
while (!(read_zsreg(zport, R0) & Tx_BUF_EMP) && --loops) {
zs_spin_unlock_cond_irq(&scc->zlock, irq);
udelay(2);
zs_spin_lock_cond_irq(&scc->zlock, irq);
}
return loops;
}
static int zs_line_drain(struct zs_port *zport, int irq)
{
struct zs_scc *scc = zport->scc;
int loops = 10000;
while (!(read_zsreg(zport, R1) & ALL_SNT) && --loops) {
zs_spin_unlock_cond_irq(&scc->zlock, irq);
udelay(2);
zs_spin_lock_cond_irq(&scc->zlock, irq);
}
return loops;
}
static void load_zsregs(struct zs_port *zport, u8 *regs, int irq)
{
/* Let the current transmission finish. */
zs_line_drain(zport, irq);
/* Load 'em up. */
write_zsreg(zport, R3, regs[3] & ~RxENABLE);
write_zsreg(zport, R5, regs[5] & ~TxENAB);
write_zsreg(zport, R4, regs[4]);
write_zsreg(zport, R9, regs[9]);
write_zsreg(zport, R1, regs[1]);
write_zsreg(zport, R2, regs[2]);
write_zsreg(zport, R10, regs[10]);
write_zsreg(zport, R14, regs[14] & ~BRENABL);
write_zsreg(zport, R11, regs[11]);
write_zsreg(zport, R12, regs[12]);
write_zsreg(zport, R13, regs[13]);
write_zsreg(zport, R14, regs[14]);
write_zsreg(zport, R15, regs[15]);
if (regs[3] & RxENABLE)
write_zsreg(zport, R3, regs[3]);
if (regs[5] & TxENAB)
write_zsreg(zport, R5, regs[5]);
return;
}
/*
* Status handling routines.
*/
/*
* zs_tx_empty() -- get the transmitter empty status
*
* Purpose: Let user call ioctl() to get info when the UART physically
* is emptied. On bus types like RS485, the transmitter must
* release the bus after transmitting. This must be done when
* the transmit shift register is empty, not be done when the
* transmit holding register is empty. This functionality
* allows an RS485 driver to be written in user space.
*/
static unsigned int zs_tx_empty(struct uart_port *uport)
{
struct zs_port *zport = to_zport(uport);
struct zs_scc *scc = zport->scc;
unsigned long flags;
u8 status;
spin_lock_irqsave(&scc->zlock, flags);
status = read_zsreg(zport, R1);
spin_unlock_irqrestore(&scc->zlock, flags);
return status & ALL_SNT ? TIOCSER_TEMT : 0;
}
static unsigned int zs_raw_get_ab_mctrl(struct zs_port *zport_a,
struct zs_port *zport_b)
{
u8 status_a, status_b;
unsigned int mctrl;
status_a = read_zsreg(zport_a, R0);
status_b = read_zsreg(zport_b, R0);
mctrl = ((status_b & CTS) ? TIOCM_CTS : 0) |
((status_b & DCD) ? TIOCM_CAR : 0) |
((status_a & DCD) ? TIOCM_RNG : 0) |
((status_a & SYNC_HUNT) ? TIOCM_DSR : 0);
return mctrl;
}
static unsigned int zs_raw_get_mctrl(struct zs_port *zport)
{
struct zs_port *zport_a = &zport->scc->zport[ZS_CHAN_A];
return zport != zport_a ? zs_raw_get_ab_mctrl(zport_a, zport) : 0;
}
static unsigned int zs_raw_xor_mctrl(struct zs_port *zport)
{
struct zs_port *zport_a = &zport->scc->zport[ZS_CHAN_A];
unsigned int mmask, mctrl, delta;
u8 mask_a, mask_b;
if (zport == zport_a)
return 0;
mask_a = zport_a->regs[15];
mask_b = zport->regs[15];
mmask = ((mask_b & CTSIE) ? TIOCM_CTS : 0) |
((mask_b & DCDIE) ? TIOCM_CAR : 0) |
((mask_a & DCDIE) ? TIOCM_RNG : 0) |
((mask_a & SYNCIE) ? TIOCM_DSR : 0);
mctrl = zport->mctrl;
if (mmask) {
mctrl &= ~mmask;
mctrl |= zs_raw_get_ab_mctrl(zport_a, zport) & mmask;
}
delta = mctrl ^ zport->mctrl;
if (delta)
zport->mctrl = mctrl;
return delta;
}
static unsigned int zs_get_mctrl(struct uart_port *uport)
{
struct zs_port *zport = to_zport(uport);
struct zs_scc *scc = zport->scc;
unsigned int mctrl;
spin_lock(&scc->zlock);
mctrl = zs_raw_get_mctrl(zport);
spin_unlock(&scc->zlock);
return mctrl;
}
static void zs_set_mctrl(struct uart_port *uport, unsigned int mctrl)
{
struct zs_port *zport = to_zport(uport);
struct zs_scc *scc = zport->scc;
struct zs_port *zport_a = &scc->zport[ZS_CHAN_A];
u8 oldloop, newloop;
spin_lock(&scc->zlock);
if (zport != zport_a) {
if (mctrl & TIOCM_DTR)
zport_a->regs[5] |= DTR;
else
zport_a->regs[5] &= ~DTR;
if (mctrl & TIOCM_RTS)
zport_a->regs[5] |= RTS;
else
zport_a->regs[5] &= ~RTS;
write_zsreg(zport_a, R5, zport_a->regs[5]);
}
/* Rarely modified, so don't poke at hardware unless necessary. */
oldloop = zport->regs[14];
newloop = oldloop;
if (mctrl & TIOCM_LOOP)
newloop |= LOOPBAK;
else
newloop &= ~LOOPBAK;
if (newloop != oldloop) {
zport->regs[14] = newloop;
write_zsreg(zport, R14, zport->regs[14]);
}
spin_unlock(&scc->zlock);
}
static void zs_raw_stop_tx(struct zs_port *zport)
{
write_zsreg(zport, R0, RES_Tx_P);
zport->tx_stopped = 1;
}
static void zs_stop_tx(struct uart_port *uport)
{
struct zs_port *zport = to_zport(uport);
struct zs_scc *scc = zport->scc;
spin_lock(&scc->zlock);
zs_raw_stop_tx(zport);
spin_unlock(&scc->zlock);
}
static void zs_raw_transmit_chars(struct zs_port *);
static void zs_start_tx(struct uart_port *uport)
{
struct zs_port *zport = to_zport(uport);
struct zs_scc *scc = zport->scc;
spin_lock(&scc->zlock);
if (zport->tx_stopped) {
zs_transmit_drain(zport, 0);
zport->tx_stopped = 0;
zs_raw_transmit_chars(zport);
}
spin_unlock(&scc->zlock);
}
static void zs_stop_rx(struct uart_port *uport)
{
struct zs_port *zport = to_zport(uport);
struct zs_scc *scc = zport->scc;
struct zs_port *zport_a = &scc->zport[ZS_CHAN_A];
spin_lock(&scc->zlock);
zport->regs[15] &= ~BRKIE;
zport->regs[1] &= ~(RxINT_MASK | TxINT_ENAB);
zport->regs[1] |= RxINT_DISAB;
if (zport != zport_a) {
/* A-side DCD tracks RI and SYNC tracks DSR. */
zport_a->regs[15] &= ~(DCDIE | SYNCIE);
write_zsreg(zport_a, R15, zport_a->regs[15]);
if (!(zport_a->regs[15] & BRKIE)) {
zport_a->regs[1] &= ~EXT_INT_ENAB;
write_zsreg(zport_a, R1, zport_a->regs[1]);
}
/* This-side DCD tracks DCD and CTS tracks CTS. */
zport->regs[15] &= ~(DCDIE | CTSIE);
zport->regs[1] &= ~EXT_INT_ENAB;
} else {
/* DCD tracks RI and SYNC tracks DSR for the B side. */
if (!(zport->regs[15] & (DCDIE | SYNCIE)))
zport->regs[1] &= ~EXT_INT_ENAB;
}
write_zsreg(zport, R15, zport->regs[15]);
write_zsreg(zport, R1, zport->regs[1]);
spin_unlock(&scc->zlock);
}
static void zs_enable_ms(struct uart_port *uport)
{
struct zs_port *zport = to_zport(uport);
struct zs_scc *scc = zport->scc;
struct zs_port *zport_a = &scc->zport[ZS_CHAN_A];
if (zport == zport_a)
return;
spin_lock(&scc->zlock);
/* Clear Ext interrupts if not being handled already. */
if (!(zport_a->regs[1] & EXT_INT_ENAB))
write_zsreg(zport_a, R0, RES_EXT_INT);
/* A-side DCD tracks RI and SYNC tracks DSR. */
zport_a->regs[1] |= EXT_INT_ENAB;
zport_a->regs[15] |= DCDIE | SYNCIE;
/* This-side DCD tracks DCD and CTS tracks CTS. */
zport->regs[15] |= DCDIE | CTSIE;
zs_raw_xor_mctrl(zport);
write_zsreg(zport_a, R1, zport_a->regs[1]);
write_zsreg(zport_a, R15, zport_a->regs[15]);
write_zsreg(zport, R15, zport->regs[15]);
spin_unlock(&scc->zlock);
}
static void zs_break_ctl(struct uart_port *uport, int break_state)
{
struct zs_port *zport = to_zport(uport);
struct zs_scc *scc = zport->scc;
unsigned long flags;
spin_lock_irqsave(&scc->zlock, flags);
if (break_state == -1)
zport->regs[5] |= SND_BRK;
else
zport->regs[5] &= ~SND_BRK;
write_zsreg(zport, R5, zport->regs[5]);
spin_unlock_irqrestore(&scc->zlock, flags);
}
/*
* Interrupt handling routines.
*/
#define Rx_BRK 0x0100 /* BREAK event software flag. */
#define Rx_SYS 0x0200 /* SysRq event software flag. */
static void zs_receive_chars(struct zs_port *zport)
{
struct uart_port *uport = &zport->port;
struct zs_scc *scc = zport->scc;
struct uart_icount *icount;
unsigned int avail, status, ch, flag;
int count;
for (count = 16; count; count--) {
spin_lock(&scc->zlock);
avail = read_zsreg(zport, R0) & Rx_CH_AV;
spin_unlock(&scc->zlock);
if (!avail)
break;
spin_lock(&scc->zlock);
status = read_zsreg(zport, R1) & (Rx_OVR | FRM_ERR | PAR_ERR);
ch = read_zsdata(zport);
spin_unlock(&scc->zlock);
flag = TTY_NORMAL;
icount = &uport->icount;
icount->rx++;
/* Handle the null char got when BREAK is removed. */
if (!ch)
status |= zport->tty_break;
if (unlikely(status &
(Rx_OVR | FRM_ERR | PAR_ERR | Rx_SYS | Rx_BRK))) {
zport->tty_break = 0;
/* Reset the error indication. */
if (status & (Rx_OVR | FRM_ERR | PAR_ERR)) {
spin_lock(&scc->zlock);
write_zsreg(zport, R0, ERR_RES);
spin_unlock(&scc->zlock);
}
if (status & (Rx_SYS | Rx_BRK)) {
icount->brk++;
/* SysRq discards the null char. */
if (status & Rx_SYS)
continue;
} else if (status & FRM_ERR)
icount->frame++;
else if (status & PAR_ERR)
icount->parity++;
if (status & Rx_OVR)
icount->overrun++;
status &= uport->read_status_mask;
if (status & Rx_BRK)
flag = TTY_BREAK;
else if (status & FRM_ERR)
flag = TTY_FRAME;
else if (status & PAR_ERR)
flag = TTY_PARITY;
}
if (uart_handle_sysrq_char(uport, ch))
continue;
uart_insert_char(uport, status, Rx_OVR, ch, flag);
}
tty_flip_buffer_push(&uport->state->port);
}
static void zs_raw_transmit_chars(struct zs_port *zport)
{
struct circ_buf *xmit = &zport->port.state->xmit;
/* XON/XOFF chars. */
if (zport->port.x_char) {
write_zsdata(zport, zport->port.x_char);
zport->port.icount.tx++;
zport->port.x_char = 0;
return;
}
/* If nothing to do or stopped or hardware stopped. */
if (uart_circ_empty(xmit) || uart_tx_stopped(&zport->port)) {
zs_raw_stop_tx(zport);
return;
}
/* Send char. */
write_zsdata(zport, xmit->buf[xmit->tail]);
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
zport->port.icount.tx++;
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(&zport->port);
/* Are we are done? */
if (uart_circ_empty(xmit))
zs_raw_stop_tx(zport);
}
static void zs_transmit_chars(struct zs_port *zport)
{
struct zs_scc *scc = zport->scc;
spin_lock(&scc->zlock);
zs_raw_transmit_chars(zport);
spin_unlock(&scc->zlock);
}
static void zs_status_handle(struct zs_port *zport, struct zs_port *zport_a)
{
struct uart_port *uport = &zport->port;
struct zs_scc *scc = zport->scc;
unsigned int delta;
u8 status, brk;
spin_lock(&scc->zlock);
/* Get status from Read Register 0. */
status = read_zsreg(zport, R0);
if (zport->regs[15] & BRKIE) {
brk = status & BRK_ABRT;
if (brk && !zport->brk) {
spin_unlock(&scc->zlock);
if (uart_handle_break(uport))
zport->tty_break = Rx_SYS;
else
zport->tty_break = Rx_BRK;
spin_lock(&scc->zlock);
}
zport->brk = brk;
}
if (zport != zport_a) {
delta = zs_raw_xor_mctrl(zport);
spin_unlock(&scc->zlock);
if (delta & TIOCM_CTS)
uart_handle_cts_change(uport,
zport->mctrl & TIOCM_CTS);
if (delta & TIOCM_CAR)
uart_handle_dcd_change(uport,
zport->mctrl & TIOCM_CAR);
if (delta & TIOCM_RNG)
uport->icount.dsr++;
if (delta & TIOCM_DSR)
uport->icount.rng++;
if (delta)
wake_up_interruptible(&uport->state->port.delta_msr_wait);
spin_lock(&scc->zlock);
}
/* Clear the status condition... */
write_zsreg(zport, R0, RES_EXT_INT);
spin_unlock(&scc->zlock);
}
/*
* This is the Z85C30 driver's generic interrupt routine.
*/
static irqreturn_t zs_interrupt(int irq, void *dev_id)
{
struct zs_scc *scc = dev_id;
struct zs_port *zport_a = &scc->zport[ZS_CHAN_A];
struct zs_port *zport_b = &scc->zport[ZS_CHAN_B];
irqreturn_t status = IRQ_NONE;
u8 zs_intreg;
int count;
/*
* NOTE: The read register 3, which holds the irq status,
* does so for both channels on each chip. Although
* the status value itself must be read from the A
* channel and is only valid when read from channel A.
* Yes... broken hardware...
*/
for (count = 16; count; count--) {
spin_lock(&scc->zlock);
zs_intreg = read_zsreg(zport_a, R3);
spin_unlock(&scc->zlock);
if (!zs_intreg)
break;
/*
* We do not like losing characters, so we prioritise
* interrupt sources a little bit differently than
* the SCC would, was it allowed to.
*/
if (zs_intreg & CHBRxIP)
zs_receive_chars(zport_b);
if (zs_intreg & CHARxIP)
zs_receive_chars(zport_a);
if (zs_intreg & CHBEXT)
zs_status_handle(zport_b, zport_a);
if (zs_intreg & CHAEXT)
zs_status_handle(zport_a, zport_a);
if (zs_intreg & CHBTxIP)
zs_transmit_chars(zport_b);
if (zs_intreg & CHATxIP)
zs_transmit_chars(zport_a);
status = IRQ_HANDLED;
}
return status;
}
/*
* Finally, routines used to initialize the serial port.
*/
static int zs_startup(struct uart_port *uport)
{
struct zs_port *zport = to_zport(uport);
struct zs_scc *scc = zport->scc;
unsigned long flags;
int irq_guard;
int ret;
irq_guard = atomic_add_return(1, &scc->irq_guard);
if (irq_guard == 1) {
ret = request_irq(zport->port.irq, zs_interrupt,
IRQF_SHARED, "scc", scc);
if (ret) {
atomic_add(-1, &scc->irq_guard);
printk(KERN_ERR "zs: can't get irq %d\n",
zport->port.irq);
return ret;
}
}
spin_lock_irqsave(&scc->zlock, flags);
/* Clear the receive FIFO. */
zs_receive_drain(zport);
/* Clear the interrupt registers. */
write_zsreg(zport, R0, ERR_RES);
write_zsreg(zport, R0, RES_Tx_P);
/* But Ext only if not being handled already. */
if (!(zport->regs[1] & EXT_INT_ENAB))
write_zsreg(zport, R0, RES_EXT_INT);
/* Finally, enable sequencing and interrupts. */
zport->regs[1] &= ~RxINT_MASK;
zport->regs[1] |= RxINT_ALL | TxINT_ENAB | EXT_INT_ENAB;
zport->regs[3] |= RxENABLE;
zport->regs[15] |= BRKIE;
write_zsreg(zport, R1, zport->regs[1]);
write_zsreg(zport, R3, zport->regs[3]);
write_zsreg(zport, R5, zport->regs[5]);
write_zsreg(zport, R15, zport->regs[15]);
/* Record the current state of RR0. */
zport->mctrl = zs_raw_get_mctrl(zport);
zport->brk = read_zsreg(zport, R0) & BRK_ABRT;
zport->tx_stopped = 1;
spin_unlock_irqrestore(&scc->zlock, flags);
return 0;
}
static void zs_shutdown(struct uart_port *uport)
{
struct zs_port *zport = to_zport(uport);
struct zs_scc *scc = zport->scc;
unsigned long flags;
int irq_guard;
spin_lock_irqsave(&scc->zlock, flags);
zport->regs[3] &= ~RxENABLE;
write_zsreg(zport, R5, zport->regs[5]);
write_zsreg(zport, R3, zport->regs[3]);
spin_unlock_irqrestore(&scc->zlock, flags);
irq_guard = atomic_add_return(-1, &scc->irq_guard);
if (!irq_guard)
free_irq(zport->port.irq, scc);
}
static void zs_reset(struct zs_port *zport)
{
struct zs_scc *scc = zport->scc;
int irq;
unsigned long flags;
spin_lock_irqsave(&scc->zlock, flags);
irq = !irqs_disabled_flags(flags);
if (!scc->initialised) {
/* Reset the pointer first, just in case... */
read_zsreg(zport, R0);
/* And let the current transmission finish. */
zs_line_drain(zport, irq);
write_zsreg(zport, R9, FHWRES);
udelay(10);
write_zsreg(zport, R9, 0);
scc->initialised = 1;
}
load_zsregs(zport, zport->regs, irq);
spin_unlock_irqrestore(&scc->zlock, flags);
}
static void zs_set_termios(struct uart_port *uport, struct ktermios *termios,
struct ktermios *old_termios)
{
struct zs_port *zport = to_zport(uport);
struct zs_scc *scc = zport->scc;
struct zs_port *zport_a = &scc->zport[ZS_CHAN_A];
int irq;
unsigned int baud, brg;
unsigned long flags;
spin_lock_irqsave(&scc->zlock, flags);
irq = !irqs_disabled_flags(flags);
/* Byte size. */
zport->regs[3] &= ~RxNBITS_MASK;
zport->regs[5] &= ~TxNBITS_MASK;
switch (termios->c_cflag & CSIZE) {
case CS5:
zport->regs[3] |= Rx5;
zport->regs[5] |= Tx5;
break;
case CS6:
zport->regs[3] |= Rx6;
zport->regs[5] |= Tx6;
break;
case CS7:
zport->regs[3] |= Rx7;
zport->regs[5] |= Tx7;
break;
case CS8:
default:
zport->regs[3] |= Rx8;
zport->regs[5] |= Tx8;
break;
}
/* Parity and stop bits. */
zport->regs[4] &= ~(XCLK_MASK | SB_MASK | PAR_ENA | PAR_EVEN);
if (termios->c_cflag & CSTOPB)
zport->regs[4] |= SB2;
else
zport->regs[4] |= SB1;
if (termios->c_cflag & PARENB)
zport->regs[4] |= PAR_ENA;
if (!(termios->c_cflag & PARODD))
zport->regs[4] |= PAR_EVEN;
switch (zport->clk_mode) {
case 64:
zport->regs[4] |= X64CLK;
break;
case 32:
zport->regs[4] |= X32CLK;
break;
case 16:
zport->regs[4] |= X16CLK;
break;
case 1:
zport->regs[4] |= X1CLK;
break;
default:
BUG();
}
baud = uart_get_baud_rate(uport, termios, old_termios, 0,
uport->uartclk / zport->clk_mode / 4);
brg = ZS_BPS_TO_BRG(baud, uport->uartclk / zport->clk_mode);
zport->regs[12] = brg & 0xff;
zport->regs[13] = (brg >> 8) & 0xff;
uart_update_timeout(uport, termios->c_cflag, baud);
uport->read_status_mask = Rx_OVR;
if (termios->c_iflag & INPCK)
uport->read_status_mask |= FRM_ERR | PAR_ERR;
serial: Fix IGNBRK handling If IGNBRK is set without either BRKINT or PARMRK set, some uart drivers send a 0x00 byte for BREAK without the TTYBREAK flag to the line discipline, when it should send either nothing or the TTYBREAK flag set. This happens because the read_status_mask masks out the BI condition, which uart_insert_char() then interprets as a normal 0x00 byte. SUS v3 is clear regarding the meaning of IGNBRK; Section 11.2.2, General Terminal Interface - Input Modes, states: "If IGNBRK is set, a break condition detected on input shall be ignored; that is, not put on the input queue and therefore not read by any process." Fix read_status_mask to include the BI bit if IGNBRK is set; the lsr status retains the BI bit if a BREAK is recv'd, which is subsequently ignored in uart_insert_char() when masked with the ignore_status_mask. Affected drivers: 8250 - all serial_txx9 mfd amba-pl010 amba-pl011 atmel_serial bfin_uart dz ip22zilog max310x mxs-auart netx-serial pnx8xxx_uart pxa sb1250-duart sccnxp serial_ks8695 sirfsoc_uart st-asc vr41xx_siu zs sunzilog fsl_lpuart sunsab ucc_uart bcm63xx_uart sunsu efm32-uart pmac_zilog mpsc msm_serial m32r_sio Unaffected drivers: omap-serial rp2 sa1100 imx icom Annotated for fixes: altera_uart mcf Drivers without break detection: 21285 xilinx-uartps altera_jtaguart apbuart arc-uart clps711x max3100 uartlite msm_serial_hs nwpserial lantiq vt8500_serial Unknown: samsung mpc52xx_uart bfin_sport_uart cpm_uart/core Fixes: Bugzilla #71651, '8250_core.c incorrectly handles IGNBRK flag' Reported-by: Ivan <athlon_@mail.ru> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-06-16 12:10:41 +00:00
if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
uport->read_status_mask |= Rx_BRK;
uport->ignore_status_mask = 0;
if (termios->c_iflag & IGNPAR)
uport->ignore_status_mask |= FRM_ERR | PAR_ERR;
if (termios->c_iflag & IGNBRK) {
uport->ignore_status_mask |= Rx_BRK;
if (termios->c_iflag & IGNPAR)
uport->ignore_status_mask |= Rx_OVR;
}
if (termios->c_cflag & CREAD)
zport->regs[3] |= RxENABLE;
else
zport->regs[3] &= ~RxENABLE;
if (zport != zport_a) {
if (!(termios->c_cflag & CLOCAL)) {
zport->regs[15] |= DCDIE;
} else
zport->regs[15] &= ~DCDIE;
if (termios->c_cflag & CRTSCTS) {
zport->regs[15] |= CTSIE;
} else
zport->regs[15] &= ~CTSIE;
zs_raw_xor_mctrl(zport);
}
/* Load up the new values. */
load_zsregs(zport, zport->regs, irq);
spin_unlock_irqrestore(&scc->zlock, flags);
}
/*
* Hack alert!
* Required solely so that the initial PROM-based console
* works undisturbed in parallel with this one.
*/
static void zs_pm(struct uart_port *uport, unsigned int state,
unsigned int oldstate)
{
struct zs_port *zport = to_zport(uport);
if (state < 3)
zport->regs[5] |= TxENAB;
else
zport->regs[5] &= ~TxENAB;
write_zsreg(zport, R5, zport->regs[5]);
}
static const char *zs_type(struct uart_port *uport)
{
return "Z85C30 SCC";
}
static void zs_release_port(struct uart_port *uport)
{
iounmap(uport->membase);
uport->membase = 0;
release_mem_region(uport->mapbase, ZS_CHAN_IO_SIZE);
}
static int zs_map_port(struct uart_port *uport)
{
if (!uport->membase)
uport->membase = ioremap_nocache(uport->mapbase,
ZS_CHAN_IO_SIZE);
if (!uport->membase) {
printk(KERN_ERR "zs: Cannot map MMIO\n");
return -ENOMEM;
}
return 0;
}
static int zs_request_port(struct uart_port *uport)
{
int ret;
if (!request_mem_region(uport->mapbase, ZS_CHAN_IO_SIZE, "scc")) {
printk(KERN_ERR "zs: Unable to reserve MMIO resource\n");
return -EBUSY;
}
ret = zs_map_port(uport);
if (ret) {
release_mem_region(uport->mapbase, ZS_CHAN_IO_SIZE);
return ret;
}
return 0;
}
static void zs_config_port(struct uart_port *uport, int flags)
{
struct zs_port *zport = to_zport(uport);
if (flags & UART_CONFIG_TYPE) {
if (zs_request_port(uport))
return;
uport->type = PORT_ZS;
zs_reset(zport);
}
}
static int zs_verify_port(struct uart_port *uport, struct serial_struct *ser)
{
struct zs_port *zport = to_zport(uport);
int ret = 0;
if (ser->type != PORT_UNKNOWN && ser->type != PORT_ZS)
ret = -EINVAL;
if (ser->irq != uport->irq)
ret = -EINVAL;
if (ser->baud_base != uport->uartclk / zport->clk_mode / 4)
ret = -EINVAL;
return ret;
}
tty: serial: constify uart_ops structures Declare uart_ops structures as const as they are only stored in the ops field of an uart_port structure. This field is of type const, so uart_ops structures having this property can be made const too. File size details before and after patching. First line of every .o file shows the file size before patching and second line shows the size after patching. text data bss dec hex filename 2977 456 64 3497 da9 drivers/tty/serial/amba-pl010.o 3169 272 64 3505 db1 drivers/tty/serial/amba-pl010.o 3109 456 0 3565 ded drivers/tty/serial/efm32-uart.o 3301 272 0 3573 df5 drivers/tty/serial/efm32-uart.o 10668 753 1 11422 2c9e drivers/tty/serial/icom.o 10860 561 1 11422 2c9e drivers/tty/serial/icom.o 23904 408 8 24320 5f00 drivers/tty/serial/ioc3_serial.o 24088 224 8 24320 5f00 drivers/tty/serial/ioc3_serial.o 10516 560 4 11080 2b48 drivers/tty/serial/ioc4_serial.o 10709 368 4 11081 2b49 drivers/tty/serial/ioc4_serial.o 7853 648 1216 9717 25f5 drivers/tty/serial/mpsc.o 8037 456 1216 9709 25ed drivers/tty/serial/mpsc.o 10248 456 0 10704 29d0 drivers/tty/serial/omap-serial.o 10440 272 0 10712 29d8 drivers/tty/serial/omap-serial.o 8122 532 1984 10638 298e drivers/tty/serial/pmac_zilog.o 8306 340 1984 10630 2986 drivers/tty/serial/pmac_zilog.o 3808 456 0 4264 10a8 drivers/tty/serial/pxa.o 4000 264 0 4264 10a8 drivers/tty/serial/pxa.o 21781 3864 0 25645 642d drivers/tty/serial/serial-tegra.o 22037 3608 0 25645 642d drivers/tty/serial/serial-tegra.o 2481 456 96 3033 bd9 drivers/tty/serial/sprd_serial.o 2673 272 96 3041 be1 drivers/tty/serial/sprd_serial.o 5534 300 512 6346 18ca drivers/tty/serial/vr41xx_siu.o 5630 204 512 6346 18ca drivers/tty/serial/vr41xx_siu.o 6730 1576 128 8434 20f2 drivers/tty/serial/vt8500_serial.o 6986 1320 128 8434 20f2 drivers/tty/serial/vt8500_serial.o Cross compiled for mips architecture. 3005 488 0 3493 da5 drivers/tty/serial/pnx8xxx_uart.o 3189 304 0 3493 da5 drivers/tty/serial/pnx8xxx_uart.o 4272 196 1056 5524 1594 drivers/tty/serial/dz.o 4368 100 1056 5524 1594 drivers/tty/serial/dz.o 6551 144 16 6711 1a37 drivers/tty/serial/ip22zilog.o 6647 48 16 6711 1a37 drivers/tty/serial/ip22zilog.o 9612 428 1520 11560 2d28 drivers/tty/serial/serial_txx9.o 9708 332 1520 11560 2d28 drivers/tty/serial/serial_txx9.o 4156 296 16 4468 1174 drivers/tty/serial/ar933x_uart.o 4252 200 16 4468 1174 drivers/tty/serial/ar933x_uart.o Cross compiled for arm archiecture. 11716 1780 44 13540 34e4 drivers/tty/serial/sirfsoc_uart.o 11808 1688 44 13540 34e4 drivers/tty/serial/sirfsoc_uart.o 13352 596 56 14004 36b4 drivers/tty/serial/amba-pl011.o 13444 504 56 14004 36b4 drivers/tty/serial/amba-pl011.o Cross compiled for sparc architecture. 4664 528 32 5224 1468 drivers/tty/serial/sunhv.o 4848 344 32 5224 1468 drivers/tty/serial/sunhv.o 8080 332 28 8440 20f8 drivers/tty/serial/sunzilog.o 8184 228 28 8440 20f8 drivers/tty/serial/sunzilog.o Cross compiled for ia64 architecture. 10226 549 472 11247 2bef drivers/tty/serial/sn_console.o 10414 365 472 11251 2bf3 drivers/tty/serial/sn_console.o The files drivers/tty/serial/zs.o, drivers/tty/serial/lpc32xx_hs.o and drivers/tty/serial/lantiq.o did not compile. Signed-off-by: Bhumika Goyal <bhumirks@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25 17:48:52 +00:00
static const struct uart_ops zs_ops = {
.tx_empty = zs_tx_empty,
.set_mctrl = zs_set_mctrl,
.get_mctrl = zs_get_mctrl,
.stop_tx = zs_stop_tx,
.start_tx = zs_start_tx,
.stop_rx = zs_stop_rx,
.enable_ms = zs_enable_ms,
.break_ctl = zs_break_ctl,
.startup = zs_startup,
.shutdown = zs_shutdown,
.set_termios = zs_set_termios,
.pm = zs_pm,
.type = zs_type,
.release_port = zs_release_port,
.request_port = zs_request_port,
.config_port = zs_config_port,
.verify_port = zs_verify_port,
};
/*
* Initialize Z85C30 port structures.
*/
static int __init zs_probe_sccs(void)
{
static int probed;
struct zs_parms zs_parms;
int chip, side, irq;
int n_chips = 0;
int i;
if (probed)
return 0;
irq = dec_interrupt[DEC_IRQ_SCC0];
if (irq >= 0) {
zs_parms.scc[n_chips] = IOASIC_SCC0;
zs_parms.irq[n_chips] = dec_interrupt[DEC_IRQ_SCC0];
n_chips++;
}
irq = dec_interrupt[DEC_IRQ_SCC1];
if (irq >= 0) {
zs_parms.scc[n_chips] = IOASIC_SCC1;
zs_parms.irq[n_chips] = dec_interrupt[DEC_IRQ_SCC1];
n_chips++;
}
if (!n_chips)
return -ENXIO;
probed = 1;
for (chip = 0; chip < n_chips; chip++) {
spin_lock_init(&zs_sccs[chip].zlock);
for (side = 0; side < ZS_NUM_CHAN; side++) {
struct zs_port *zport = &zs_sccs[chip].zport[side];
struct uart_port *uport = &zport->port;
zport->scc = &zs_sccs[chip];
zport->clk_mode = 16;
uport->irq = zs_parms.irq[chip];
uport->uartclk = ZS_CLOCK;
uport->fifosize = 1;
uport->iotype = UPIO_MEM;
uport->flags = UPF_BOOT_AUTOCONF;
uport->ops = &zs_ops;
uport->line = chip * ZS_NUM_CHAN + side;
uport->mapbase = dec_kn_slot_base +
zs_parms.scc[chip] +
(side ^ ZS_CHAN_B) * ZS_CHAN_IO_SIZE;
for (i = 0; i < ZS_NUM_REGS; i++)
zport->regs[i] = zs_init_regs[i];
}
}
return 0;
}
#ifdef CONFIG_SERIAL_ZS_CONSOLE
static void zs_console_putchar(struct uart_port *uport, int ch)
{
struct zs_port *zport = to_zport(uport);
struct zs_scc *scc = zport->scc;
int irq;
unsigned long flags;
spin_lock_irqsave(&scc->zlock, flags);
irq = !irqs_disabled_flags(flags);
if (zs_transmit_drain(zport, irq))
write_zsdata(zport, ch);
spin_unlock_irqrestore(&scc->zlock, flags);
}
/*
* Print a string to the serial port trying not to disturb
* any possible real use of the port...
*/
static void zs_console_write(struct console *co, const char *s,
unsigned int count)
{
int chip = co->index / ZS_NUM_CHAN, side = co->index % ZS_NUM_CHAN;
struct zs_port *zport = &zs_sccs[chip].zport[side];
struct zs_scc *scc = zport->scc;
unsigned long flags;
u8 txint, txenb;
int irq;
/* Disable transmit interrupts and enable the transmitter. */
spin_lock_irqsave(&scc->zlock, flags);
txint = zport->regs[1];
txenb = zport->regs[5];
if (txint & TxINT_ENAB) {
zport->regs[1] = txint & ~TxINT_ENAB;
write_zsreg(zport, R1, zport->regs[1]);
}
if (!(txenb & TxENAB)) {
zport->regs[5] = txenb | TxENAB;
write_zsreg(zport, R5, zport->regs[5]);
}
spin_unlock_irqrestore(&scc->zlock, flags);
uart_console_write(&zport->port, s, count, zs_console_putchar);
/* Restore transmit interrupts and the transmitter enable. */
spin_lock_irqsave(&scc->zlock, flags);
irq = !irqs_disabled_flags(flags);
zs_line_drain(zport, irq);
if (!(txenb & TxENAB)) {
zport->regs[5] &= ~TxENAB;
write_zsreg(zport, R5, zport->regs[5]);
}
if (txint & TxINT_ENAB) {
zport->regs[1] |= TxINT_ENAB;
write_zsreg(zport, R1, zport->regs[1]);
/* Resume any transmission as the TxIP bit won't be set. */
if (!zport->tx_stopped)
zs_raw_transmit_chars(zport);
}
spin_unlock_irqrestore(&scc->zlock, flags);
}
/*
* Setup serial console baud/bits/parity. We do two things here:
* - construct a cflag setting for the first uart_open()
* - initialise the serial port
* Return non-zero if we didn't find a serial port.
*/
static int __init zs_console_setup(struct console *co, char *options)
{
int chip = co->index / ZS_NUM_CHAN, side = co->index % ZS_NUM_CHAN;
struct zs_port *zport = &zs_sccs[chip].zport[side];
struct uart_port *uport = &zport->port;
int baud = 9600;
int bits = 8;
int parity = 'n';
int flow = 'n';
int ret;
ret = zs_map_port(uport);
if (ret)
return ret;
zs_reset(zport);
zs_pm(uport, 0, -1);
if (options)
uart_parse_options(options, &baud, &parity, &bits, &flow);
return uart_set_options(uport, co, baud, parity, bits, flow);
}
static struct uart_driver zs_reg;
static struct console zs_console = {
.name = "ttyS",
.write = zs_console_write,
.device = uart_console_device,
.setup = zs_console_setup,
.flags = CON_PRINTBUFFER,
.index = -1,
.data = &zs_reg,
};
/*
* Register console.
*/
static int __init zs_serial_console_init(void)
{
int ret;
ret = zs_probe_sccs();
if (ret)
return ret;
register_console(&zs_console);
return 0;
}
console_initcall(zs_serial_console_init);
#define SERIAL_ZS_CONSOLE &zs_console
#else
#define SERIAL_ZS_CONSOLE NULL
#endif /* CONFIG_SERIAL_ZS_CONSOLE */
static struct uart_driver zs_reg = {
.owner = THIS_MODULE,
.driver_name = "serial",
.dev_name = "ttyS",
.major = TTY_MAJOR,
.minor = 64,
.nr = ZS_NUM_SCCS * ZS_NUM_CHAN,
.cons = SERIAL_ZS_CONSOLE,
};
/* zs_init inits the driver. */
static int __init zs_init(void)
{
int i, ret;
pr_info("%s%s\n", zs_name, zs_version);
/* Find out how many Z85C30 SCCs we have. */
ret = zs_probe_sccs();
if (ret)
return ret;
ret = uart_register_driver(&zs_reg);
if (ret)
return ret;
for (i = 0; i < ZS_NUM_SCCS * ZS_NUM_CHAN; i++) {
struct zs_scc *scc = &zs_sccs[i / ZS_NUM_CHAN];
struct zs_port *zport = &scc->zport[i % ZS_NUM_CHAN];
struct uart_port *uport = &zport->port;
if (zport->scc)
uart_add_one_port(&zs_reg, uport);
}
return 0;
}
static void __exit zs_exit(void)
{
int i;
for (i = ZS_NUM_SCCS * ZS_NUM_CHAN - 1; i >= 0; i--) {
struct zs_scc *scc = &zs_sccs[i / ZS_NUM_CHAN];
struct zs_port *zport = &scc->zport[i % ZS_NUM_CHAN];
struct uart_port *uport = &zport->port;
if (zport->scc)
uart_remove_one_port(&zs_reg, uport);
}
uart_unregister_driver(&zs_reg);
}
module_init(zs_init);
module_exit(zs_exit);