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tty/serial/8250: make UART_MCR register access consistent
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Introduce serial8250_out_MCR() and serial8250_in_MCR() routines, that
replace following calls:

serial_out(port, UART_MCR, val)
serial_port_out(up, UART_MCR, val)
serial_in(port, UART_MCR)

This patch is needed in order to integrate reading/writing of MCR
signals via SERIAL_MCTRL_GPIO infrastructure later.

Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Yegor Yefremov authored and Greg Kroah-Hartman committed Jun 25, 2016
1 parent 692aa19 commit 36fd95b
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Showing 3 changed files with 35 additions and 26 deletions.
10 changes: 10 additions & 0 deletions drivers/tty/serial/8250/8250.h
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Original file line number Diff line number Diff line change
Expand Up @@ -129,6 +129,16 @@ void serial8250_rpm_put(struct uart_8250_port *p);
int serial8250_em485_init(struct uart_8250_port *p);
void serial8250_em485_destroy(struct uart_8250_port *p);

static inline void serial8250_out_MCR(struct uart_8250_port *up, int value)
{
serial_out(up, UART_MCR, value);
}

static inline int serial8250_in_MCR(struct uart_8250_port *up)
{
return serial_in(up, UART_MCR);
}

#if defined(__alpha__) && !defined(CONFIG_PCI)
/*
* Digital did something really horribly wrong with the OUT1 and OUT2
Expand Down
4 changes: 2 additions & 2 deletions drivers/tty/serial/8250/8250_omap.c
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Original file line number Diff line number Diff line change
Expand Up @@ -280,7 +280,7 @@ static void omap8250_restore_regs(struct uart_8250_port *up)
serial_out(up, UART_EFR, UART_EFR_ECB);

serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
serial_out(up, UART_MCR, UART_MCR_TCRTLR);
serial8250_out_MCR(up, UART_MCR_TCRTLR);
serial_out(up, UART_FCR, up->fcr);

omap8250_update_scr(up, priv);
Expand All @@ -296,7 +296,7 @@ static void omap8250_restore_regs(struct uart_8250_port *up)
serial_out(up, UART_LCR, 0);

/* drop TCR + TLR access, we setup XON/XOFF later */
serial_out(up, UART_MCR, up->mcr);
serial8250_out_MCR(up, up->mcr);
serial_out(up, UART_IER, up->ier);

serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
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47 changes: 23 additions & 24 deletions drivers/tty/serial/8250/8250_port.c
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Original file line number Diff line number Diff line change
Expand Up @@ -527,13 +527,13 @@ static void serial8250_clear_fifos(struct uart_8250_port *p)

static inline void serial8250_em485_rts_after_send(struct uart_8250_port *p)
{
unsigned char mcr = serial_in(p, UART_MCR);
unsigned char mcr = serial8250_in_MCR(p);

if (p->port.rs485.flags & SER_RS485_RTS_AFTER_SEND)
mcr |= UART_MCR_RTS;
else
mcr &= ~UART_MCR_RTS;
serial_out(p, UART_MCR, mcr);
serial8250_out_MCR(p, mcr);
}

static void serial8250_em485_handle_start_tx(unsigned long arg);
Expand Down Expand Up @@ -785,10 +785,10 @@ static int size_fifo(struct uart_8250_port *up)
old_lcr = serial_in(up, UART_LCR);
serial_out(up, UART_LCR, 0);
old_fcr = serial_in(up, UART_FCR);
old_mcr = serial_in(up, UART_MCR);
old_mcr = serial8250_in_MCR(up);
serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
serial_out(up, UART_MCR, UART_MCR_LOOP);
serial8250_out_MCR(up, UART_MCR_LOOP);
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
old_dl = serial_dl_read(up);
serial_dl_write(up, 0x0001);
Expand All @@ -800,7 +800,7 @@ static int size_fifo(struct uart_8250_port *up)
(count < 256); count++)
serial_in(up, UART_RX);
serial_out(up, UART_FCR, old_fcr);
serial_out(up, UART_MCR, old_mcr);
serial8250_out_MCR(up, old_mcr);
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
serial_dl_write(up, old_dl);
serial_out(up, UART_LCR, old_lcr);
Expand Down Expand Up @@ -1040,17 +1040,17 @@ static void autoconfig_16550a(struct uart_8250_port *up)
* it's changed. If so, set baud_base in EXCR2 to 921600. -- dwmw2
*/
serial_out(up, UART_LCR, 0);
status1 = serial_in(up, UART_MCR);
status1 = serial8250_in_MCR(up);
serial_out(up, UART_LCR, 0xE0);
status2 = serial_in(up, 0x02); /* EXCR1 */

if (!((status2 ^ status1) & UART_MCR_LOOP)) {
serial_out(up, UART_LCR, 0);
serial_out(up, UART_MCR, status1 ^ UART_MCR_LOOP);
serial8250_out_MCR(up, status1 ^ UART_MCR_LOOP);
serial_out(up, UART_LCR, 0xE0);
status2 = serial_in(up, 0x02); /* EXCR1 */
serial_out(up, UART_LCR, 0);
serial_out(up, UART_MCR, status1);
serial8250_out_MCR(up, status1);

if ((status2 ^ status1) & UART_MCR_LOOP) {
unsigned short quot;
Expand Down Expand Up @@ -1224,7 +1224,7 @@ static void autoconfig(struct uart_8250_port *up)
}
}

save_mcr = serial_in(up, UART_MCR);
save_mcr = serial8250_in_MCR(up);
save_lcr = serial_in(up, UART_LCR);

/*
Expand All @@ -1237,9 +1237,9 @@ static void autoconfig(struct uart_8250_port *up)
* that conflicts with COM 1-4 --- we hope!
*/
if (!(port->flags & UPF_SKIP_TEST)) {
serial_out(up, UART_MCR, UART_MCR_LOOP | 0x0A);
serial8250_out_MCR(up, UART_MCR_LOOP | 0x0A);
status1 = serial_in(up, UART_MSR) & 0xF0;
serial_out(up, UART_MCR, save_mcr);
serial8250_out_MCR(up, save_mcr);
if (status1 != 0x90) {
spin_unlock_irqrestore(&port->lock, flags);
DEBUG_AUTOCONF("LOOP test failed (%02x) ",
Expand Down Expand Up @@ -1305,7 +1305,7 @@ static void autoconfig(struct uart_8250_port *up)
if (port->type == PORT_RSA)
serial_out(up, UART_RSA_FRR, 0);
#endif
serial_out(up, UART_MCR, save_mcr);
serial8250_out_MCR(up, save_mcr);
serial8250_clear_fifos(up);
serial_in(up, UART_RX);
if (up->capabilities & UART_CAP_UUE)
Expand Down Expand Up @@ -1353,19 +1353,18 @@ static void autoconfig_irq(struct uart_8250_port *up)

/* forget possible initially masked and pending IRQ */
probe_irq_off(probe_irq_on());
save_mcr = serial_in(up, UART_MCR);
save_mcr = serial8250_in_MCR(up);
save_ier = serial_in(up, UART_IER);
serial_out(up, UART_MCR, UART_MCR_OUT1 | UART_MCR_OUT2);
serial8250_out_MCR(up, UART_MCR_OUT1 | UART_MCR_OUT2);

irqs = probe_irq_on();
serial_out(up, UART_MCR, 0);
serial8250_out_MCR(up, 0);
udelay(10);
if (port->flags & UPF_FOURPORT) {
serial_out(up, UART_MCR,
UART_MCR_DTR | UART_MCR_RTS);
serial8250_out_MCR(up, UART_MCR_DTR | UART_MCR_RTS);
} else {
serial_out(up, UART_MCR,
UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2);
serial8250_out_MCR(up,
UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2);
}
serial_out(up, UART_IER, 0x0f); /* enable all intrs */
serial_in(up, UART_LSR);
Expand All @@ -1376,7 +1375,7 @@ static void autoconfig_irq(struct uart_8250_port *up)
udelay(20);
irq = probe_irq_off(irqs);

serial_out(up, UART_MCR, save_mcr);
serial8250_out_MCR(up, save_mcr);
serial_out(up, UART_IER, save_ier);

if (port->flags & UPF_FOURPORT)
Expand Down Expand Up @@ -1549,14 +1548,14 @@ static inline void start_tx_rs485(struct uart_port *port)
del_timer(&em485->stop_tx_timer);
em485->active_timer = NULL;

mcr = serial_in(up, UART_MCR);
mcr = serial8250_in_MCR(up);
if (!!(up->port.rs485.flags & SER_RS485_RTS_ON_SEND) !=
!!(mcr & UART_MCR_RTS)) {
if (up->port.rs485.flags & SER_RS485_RTS_ON_SEND)
mcr |= UART_MCR_RTS;
else
mcr &= ~UART_MCR_RTS;
serial_out(up, UART_MCR, mcr);
serial8250_out_MCR(up, mcr);

if (up->port.rs485.delay_rts_before_send > 0) {
em485->active_timer = &em485->start_tx_timer;
Expand Down Expand Up @@ -1943,7 +1942,7 @@ void serial8250_do_set_mctrl(struct uart_port *port, unsigned int mctrl)

mcr = (mcr & up->mcr_mask) | up->mcr_force | up->mcr;

serial_port_out(port, UART_MCR, mcr);
serial8250_out_MCR(up, mcr);
}
EXPORT_SYMBOL_GPL(serial8250_do_set_mctrl);

Expand Down Expand Up @@ -3090,7 +3089,7 @@ static void serial8250_console_restore(struct uart_8250_port *up)

serial8250_set_divisor(port, baud, quot, frac);
serial_port_out(port, UART_LCR, up->lcr);
serial_port_out(port, UART_MCR, UART_MCR_DTR | UART_MCR_RTS);
serial8250_out_MCR(up, UART_MCR_DTR | UART_MCR_RTS);
}

/*
Expand Down

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