[RFC] OMAP: Serial: Define register access modes in LCR

From: Emeltchenko Andrei
Date: Tue Nov 16 2010 - 06:47:32 EST


From: Andrei Emeltchenko <andrei.emeltchenko@xxxxxxxxx>

Access to some registers depends on register access mode
Three different modes are available for OMAP (at least)
* Operational mode LCR_REG[7] = 0x0
* Configuration mode A LCR_REG[7] = 0x1 and LCR_REG[7:0]! = 0xBF
* Configuration mode B LCR_REG[7] = 0x1 and LCR_REG[7:0] = 0xBF

Define access modes and remove redefinitions and magic numbers
in serial drivers (and later in bluetooth driver).

Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@xxxxxxxxx>
---
arch/arm/mach-omap2/serial.c | 12 ++++----
arch/arm/plat-omap/include/plat/omap-serial.h | 9 ------
drivers/serial/8250.c | 26 +++++++++---------
drivers/serial/omap-serial.c | 34 ++++++++++++------------
include/linux/serial_reg.h | 6 ++++
5 files changed, 42 insertions(+), 45 deletions(-)

diff --git a/arch/arm/mach-omap2/serial.c b/arch/arm/mach-omap2/serial.c
index edd7c99..14c8715 100644
--- a/arch/arm/mach-omap2/serial.c
+++ b/arch/arm/mach-omap2/serial.c
@@ -218,7 +218,7 @@ static void omap_uart_save_context(struct omap_uart_state *uart)
return;

lcr = serial_read_reg(uart, UART_LCR);
- serial_write_reg(uart, UART_LCR, 0xBF);
+ serial_write_reg(uart, UART_LCR, UART_LCR_CONF_MODE_B);
uart->dll = serial_read_reg(uart, UART_DLL);
uart->dlh = serial_read_reg(uart, UART_DLM);
serial_write_reg(uart, UART_LCR, lcr);
@@ -226,7 +226,7 @@ static void omap_uart_save_context(struct omap_uart_state *uart)
uart->sysc = serial_read_reg(uart, UART_OMAP_SYSC);
uart->scr = serial_read_reg(uart, UART_OMAP_SCR);
uart->wer = serial_read_reg(uart, UART_OMAP_WER);
- serial_write_reg(uart, UART_LCR, 0x80);
+ serial_write_reg(uart, UART_LCR, UART_LCR_CONF_MODE_A);
uart->mcr = serial_read_reg(uart, UART_MCR);
serial_write_reg(uart, UART_LCR, lcr);

@@ -250,19 +250,19 @@ static void omap_uart_restore_context(struct omap_uart_state *uart)
else
serial_write_reg(uart, UART_OMAP_MDR1, UART_OMAP_MDR1_DISABLE);

- serial_write_reg(uart, UART_LCR, 0xBF); /* Config B mode */
+ serial_write_reg(uart, UART_LCR, UART_LCR_CONF_MODE_B);
efr = serial_read_reg(uart, UART_EFR);
serial_write_reg(uart, UART_EFR, UART_EFR_ECB);
serial_write_reg(uart, UART_LCR, 0x0); /* Operational mode */
serial_write_reg(uart, UART_IER, 0x0);
- serial_write_reg(uart, UART_LCR, 0xBF); /* Config B mode */
+ serial_write_reg(uart, UART_LCR, UART_LCR_CONF_MODE_B);
serial_write_reg(uart, UART_DLL, uart->dll);
serial_write_reg(uart, UART_DLM, uart->dlh);
serial_write_reg(uart, UART_LCR, 0x0); /* Operational mode */
serial_write_reg(uart, UART_IER, uart->ier);
- serial_write_reg(uart, UART_LCR, 0x80);
+ serial_write_reg(uart, UART_LCR, UART_LCR_CONF_MODE_A);
serial_write_reg(uart, UART_MCR, uart->mcr);
- serial_write_reg(uart, UART_LCR, 0xBF); /* Config B mode */
+ serial_write_reg(uart, UART_LCR, UART_LCR_CONF_MODE_B);
serial_write_reg(uart, UART_EFR, efr);
serial_write_reg(uart, UART_LCR, UART_LCR_WLEN8);
serial_write_reg(uart, UART_OMAP_SCR, uart->scr);
diff --git a/arch/arm/plat-omap/include/plat/omap-serial.h b/arch/arm/plat-omap/include/plat/omap-serial.h
index 6a17880..b3e0bad 100644
--- a/arch/arm/plat-omap/include/plat/omap-serial.h
+++ b/arch/arm/plat-omap/include/plat/omap-serial.h
@@ -33,15 +33,6 @@

#define OMAP_MODE13X_SPEED 230400

-/*
- * LCR = 0XBF: Switch to Configuration Mode B.
- * In configuration mode b allow access
- * to EFR,DLL,DLH.
- * Reference OMAP TRM Chapter 17
- * Section: 1.4.3 Mode Selection
- */
-#define OMAP_UART_LCR_CONF_MDB 0XBF
-
/* WER = 0x7F
* Enable module level wakeup in WER reg
*/
diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c
index 4d8e14b..aaf9907 100644
--- a/drivers/serial/8250.c
+++ b/drivers/serial/8250.c
@@ -653,13 +653,13 @@ static void serial8250_set_sleep(struct uart_8250_port *p, int sleep)
{
if (p->capabilities & UART_CAP_SLEEP) {
if (p->capabilities & UART_CAP_EFR) {
- serial_outp(p, UART_LCR, 0xBF);
+ serial_outp(p, UART_LCR, UART_LCR_CONF_MODE_B);
serial_outp(p, UART_EFR, UART_EFR_ECB);
serial_outp(p, UART_LCR, 0);
}
serial_outp(p, UART_IER, sleep ? UART_IERX_SLEEP : 0);
if (p->capabilities & UART_CAP_EFR) {
- serial_outp(p, UART_LCR, 0xBF);
+ serial_outp(p, UART_LCR, UART_LCR_CONF_MODE_B);
serial_outp(p, UART_EFR, 0);
serial_outp(p, UART_LCR, 0);
}
@@ -752,7 +752,7 @@ static int size_fifo(struct uart_8250_port *up)
serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO |
UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
serial_outp(up, UART_MCR, UART_MCR_LOOP);
- serial_outp(up, UART_LCR, UART_LCR_DLAB);
+ serial_outp(up, UART_LCR, UART_LCR_CONF_MODE_A);
old_dl = serial_dl_read(up);
serial_dl_write(up, 0x0001);
serial_outp(up, UART_LCR, 0x03);
@@ -764,7 +764,7 @@ static int size_fifo(struct uart_8250_port *up)
serial_inp(up, UART_RX);
serial_outp(up, UART_FCR, old_fcr);
serial_outp(up, UART_MCR, old_mcr);
- serial_outp(up, UART_LCR, UART_LCR_DLAB);
+ serial_outp(up, UART_LCR, UART_LCR_CONF_MODE_A);
serial_dl_write(up, old_dl);
serial_outp(up, UART_LCR, old_lcr);

@@ -782,7 +782,7 @@ static unsigned int autoconfig_read_divisor_id(struct uart_8250_port *p)
unsigned int id;

old_lcr = serial_inp(p, UART_LCR);
- serial_outp(p, UART_LCR, UART_LCR_DLAB);
+ serial_outp(p, UART_LCR, UART_LCR_CONF_MODE_A);

old_dll = serial_inp(p, UART_DLL);
old_dlm = serial_inp(p, UART_DLM);
@@ -836,7 +836,7 @@ static void autoconfig_has_efr(struct uart_8250_port *up)
* recommended for new designs).
*/
up->acr = 0;
- serial_out(up, UART_LCR, 0xBF);
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
serial_out(up, UART_EFR, UART_EFR_ECB);
serial_out(up, UART_LCR, 0x00);
id1 = serial_icr_read(up, UART_ID1);
@@ -945,7 +945,7 @@ static void autoconfig_16550a(struct uart_8250_port *up)
* Check for presence of the EFR when DLAB is set.
* Only ST16C650V1 UARTs pass this test.
*/
- serial_outp(up, UART_LCR, UART_LCR_DLAB);
+ serial_outp(up, UART_LCR, UART_LCR_CONF_MODE_A);
if (serial_in(up, UART_EFR) == 0) {
serial_outp(up, UART_EFR, 0xA8);
if (serial_in(up, UART_EFR) != 0) {
@@ -963,7 +963,7 @@ static void autoconfig_16550a(struct uart_8250_port *up)
* Maybe it requires 0xbf to be written to the LCR.
* (other ST16C650V2 UARTs, TI16C752A, etc)
*/
- serial_outp(up, UART_LCR, 0xBF);
+ serial_outp(up, UART_LCR, UART_LCR_CONF_MODE_B);
if (serial_in(up, UART_EFR) == 0 && !broken_efr(up)) {
DEBUG_AUTOCONF("EFRv2 ");
autoconfig_has_efr(up);
@@ -1024,7 +1024,7 @@ static void autoconfig_16550a(struct uart_8250_port *up)
serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO | UART_FCR7_64BYTE);
status1 = serial_in(up, UART_IIR) >> 5;
serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO);
- serial_outp(up, UART_LCR, UART_LCR_DLAB);
+ serial_outp(up, UART_LCR, UART_LCR_CONF_MODE_A);
serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO | UART_FCR7_64BYTE);
status2 = serial_in(up, UART_IIR) >> 5;
serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO);
@@ -1183,7 +1183,7 @@ static void autoconfig(struct uart_8250_port *up, unsigned int probeflags)
* We also initialise the EFR (if any) to zero for later. The
* EFR occupies the same register location as the FCR and IIR.
*/
- serial_outp(up, UART_LCR, 0xBF);
+ serial_outp(up, UART_LCR, UART_LCR_CONF_MODE_B);
serial_outp(up, UART_EFR, 0);
serial_outp(up, UART_LCR, 0);

@@ -1952,7 +1952,7 @@ static int serial8250_startup(struct uart_port *port)
if (up->port.type == PORT_16C950) {
/* Wake up and initialize UART */
up->acr = 0;
- serial_outp(up, UART_LCR, 0xBF);
+ serial_outp(up, UART_LCR, UART_LCR_CONF_MODE_B);
serial_outp(up, UART_EFR, UART_EFR_ECB);
serial_outp(up, UART_IER, 0);
serial_outp(up, UART_LCR, 0);
@@ -2002,7 +2002,7 @@ static int serial8250_startup(struct uart_port *port)
if (up->port.type == PORT_16850) {
unsigned char fctr;

- serial_outp(up, UART_LCR, 0xbf);
+ serial_outp(up, UART_LCR, UART_LCR_CONF_MODE_B);

fctr = serial_inp(up, UART_FCTR) & ~(UART_FCTR_RX|UART_FCTR_TX);
serial_outp(up, UART_FCTR, fctr | UART_FCTR_TRGD | UART_FCTR_RX);
@@ -2363,7 +2363,7 @@ serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios,
if (termios->c_cflag & CRTSCTS)
efr |= UART_EFR_CTS;

- serial_outp(up, UART_LCR, 0xBF);
+ serial_outp(up, UART_LCR, UART_LCR_CONF_MODE_B);
serial_outp(up, UART_EFR, efr);
}

diff --git a/drivers/serial/omap-serial.c b/drivers/serial/omap-serial.c
index 03a96db..1201eff 100644
--- a/drivers/serial/omap-serial.c
+++ b/drivers/serial/omap-serial.c
@@ -570,7 +570,7 @@ serial_omap_configure_xonxoff
unsigned char efr = 0;

up->lcr = serial_in(up, UART_LCR);
- serial_out(up, UART_LCR, OMAP_UART_LCR_CONF_MDB);
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
up->efr = serial_in(up, UART_EFR);
serial_out(up, UART_EFR, up->efr & ~UART_EFR_ECB);

@@ -598,7 +598,7 @@ serial_omap_configure_xonxoff
efr |= OMAP_UART_SW_RX;

serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
- serial_out(up, UART_LCR, UART_LCR_DLAB);
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);

up->mcr = serial_in(up, UART_MCR);

@@ -612,14 +612,14 @@ serial_omap_configure_xonxoff
up->mcr |= UART_MCR_XONANY;

serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
- serial_out(up, UART_LCR, OMAP_UART_LCR_CONF_MDB);
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG);
/* Enable special char function UARTi.EFR_REG[5] and
* load the new software flow control mode IXON or IXOFF
* and restore the UARTi.EFR_REG[4] ENHANCED_EN value.
*/
serial_out(up, UART_EFR, efr | UART_EFR_SCD);
- serial_out(up, UART_LCR, UART_LCR_DLAB);
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);

serial_out(up, UART_MCR, up->mcr & ~UART_MCR_TCRTLR);
serial_out(up, UART_LCR, up->lcr);
@@ -724,22 +724,22 @@ serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,
* baud clock is not running
* DLL_REG and DLH_REG set to 0.
*/
- serial_out(up, UART_LCR, UART_LCR_DLAB);
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
serial_out(up, UART_DLL, 0);
serial_out(up, UART_DLM, 0);
serial_out(up, UART_LCR, 0);

- serial_out(up, UART_LCR, OMAP_UART_LCR_CONF_MDB);
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);

up->efr = serial_in(up, UART_EFR);
serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);

- serial_out(up, UART_LCR, UART_LCR_DLAB);
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
up->mcr = serial_in(up, UART_MCR);
serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
/* FIFO ENABLE, DMA MODE */
serial_out(up, UART_FCR, up->fcr);
- serial_out(up, UART_LCR, OMAP_UART_LCR_CONF_MDB);
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);

if (up->use_dma) {
serial_out(up, UART_TI752_TLR, 0);
@@ -748,27 +748,27 @@ serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,
}

serial_out(up, UART_EFR, up->efr);
- serial_out(up, UART_LCR, UART_LCR_DLAB);
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
serial_out(up, UART_MCR, up->mcr);

/* Protocol, Baud Rate, and Interrupt Settings */

serial_out(up, UART_OMAP_MDR1, UART_OMAP_MDR1_DISABLE);
- serial_out(up, UART_LCR, OMAP_UART_LCR_CONF_MDB);
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);

up->efr = serial_in(up, UART_EFR);
serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);

serial_out(up, UART_LCR, 0);
serial_out(up, UART_IER, 0);
- serial_out(up, UART_LCR, OMAP_UART_LCR_CONF_MDB);
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);

serial_out(up, UART_DLL, quot & 0xff); /* LS of divisor */
serial_out(up, UART_DLM, quot >> 8); /* MS of divisor */

serial_out(up, UART_LCR, 0);
serial_out(up, UART_IER, up->ier);
- serial_out(up, UART_LCR, OMAP_UART_LCR_CONF_MDB);
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);

serial_out(up, UART_EFR, up->efr);
serial_out(up, UART_LCR, cval);
@@ -782,18 +782,18 @@ serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,

if (termios->c_cflag & CRTSCTS) {
efr |= (UART_EFR_CTS | UART_EFR_RTS);
- serial_out(up, UART_LCR, UART_LCR_DLAB);
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);

up->mcr = serial_in(up, UART_MCR);
serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);

- serial_out(up, UART_LCR, OMAP_UART_LCR_CONF_MDB);
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
up->efr = serial_in(up, UART_EFR);
serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);

serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG);
serial_out(up, UART_EFR, efr); /* Enable AUTORTS and AUTOCTS */
- serial_out(up, UART_LCR, UART_LCR_DLAB);
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
serial_out(up, UART_MCR, up->mcr | UART_MCR_RTS);
serial_out(up, UART_LCR, cval);
}
@@ -815,13 +815,13 @@ serial_omap_pm(struct uart_port *port, unsigned int state,
unsigned char efr;

dev_dbg(up->port.dev, "serial_omap_pm+%d\n", up->pdev->id);
- serial_out(up, UART_LCR, OMAP_UART_LCR_CONF_MDB);
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
efr = serial_in(up, UART_EFR);
serial_out(up, UART_EFR, efr | UART_EFR_ECB);
serial_out(up, UART_LCR, 0);

serial_out(up, UART_IER, (state != 0) ? UART_IERX_SLEEP : 0);
- serial_out(up, UART_LCR, OMAP_UART_LCR_CONF_MDB);
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
serial_out(up, UART_EFR, efr);
serial_out(up, UART_LCR, 0);
/* Enable module level wake up */
diff --git a/include/linux/serial_reg.h b/include/linux/serial_reg.h
index 6f38234..a371a0d 100644
--- a/include/linux/serial_reg.h
+++ b/include/linux/serial_reg.h
@@ -99,6 +99,12 @@
#define UART_LCR_WLEN7 0x02 /* Wordlength: 7 bits */
#define UART_LCR_WLEN8 0x03 /* Wordlength: 8 bits */

+/*
+ * These are definitions for register access modes using LCR
+ */
+#define UART_LCR_CONF_MODE_A 0x80 /* Configutation mode A */
+#define UART_LCR_CONF_MODE_B 0xBF /* Configutation mode B */
+
#define UART_MCR 4 /* Out: Modem Control Register */
#define UART_MCR_CLKSEL 0x80 /* Divide clock by 4 (TI16C752, EFR[4]=1) */
#define UART_MCR_TCRTLR 0x40 /* Access TCR/TLR (TI16C752, EFR[4]=1) */
--
1.7.0.4

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