serial: Add OMAP high-speed UART driver

This patch adds driver support for OMAP2/3/4 high speed UART.

The driver is made separate from 8250 driver as we cannot
over load 8250 driver with omap platform specific configuration for
features like DMA, it makes easier to implement features like DMA and
hardware flow control and software flow control configuration with
this driver as required for the omap-platform.
This patch involves only the core driver and its dependent.

Cc: Tony Lindgren <tony@atomide.com>
Signed-off-by: Govindraj.R <govindraj.raja@ti.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
This commit is contained in:
Govindraj.R 2010-09-27 20:20:49 +05:30 committed by Kevin Hilman
parent 52663aea10
commit b612633b59
5 changed files with 1493 additions and 0 deletions

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@ -0,0 +1,129 @@
/*
* Driver for OMAP-UART controller.
* Based on drivers/serial/8250.c
*
* Copyright (C) 2010 Texas Instruments.
*
* Authors:
* Govindraj R <govindraj.raja@ti.com>
* Thara Gopinath <thara@ti.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
#ifndef __OMAP_SERIAL_H__
#define __OMAP_SERIAL_H__
#include <linux/serial_core.h>
#include <linux/platform_device.h>
#include <plat/control.h>
#include <plat/mux.h>
#define DRIVER_NAME "omap-hsuart"
/*
* Use tty device name as ttyO, [O -> OMAP]
* in bootargs we specify as console=ttyO0 if uart1
* is used as console uart.
*/
#define OMAP_SERIAL_NAME "ttyO"
#define OMAP_MDR1_DISABLE 0x07
#define OMAP_MDR1_MODE13X 0x03
#define OMAP_MDR1_MODE16X 0x00
#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
*/
#define OMAP_UART_WER_MOD_WKUP 0X7F
/* Enable XON/XOFF flow control on output */
#define OMAP_UART_SW_TX 0x04
/* Enable XON/XOFF flow control on input */
#define OMAP_UART_SW_RX 0x04
#define OMAP_UART_SYSC_RESET 0X07
#define OMAP_UART_TCR_TRIG 0X0F
#define OMAP_UART_SW_CLR 0XF0
#define OMAP_UART_FIFO_CLR 0X06
#define OMAP_UART_DMA_CH_FREE -1
#define RX_TIMEOUT (3 * HZ)
#define OMAP_MAX_HSUART_PORTS 4
#define MSR_SAVE_FLAGS UART_MSR_ANY_DELTA
struct omap_uart_port_info {
bool dma_enabled; /* To specify DMA Mode */
unsigned int uartclk; /* UART clock rate */
void __iomem *membase; /* ioremap cookie or NULL */
resource_size_t mapbase; /* resource base */
unsigned long irqflags; /* request_irq flags */
upf_t flags; /* UPF_* flags */
};
struct uart_omap_dma {
u8 uart_dma_tx;
u8 uart_dma_rx;
int rx_dma_channel;
int tx_dma_channel;
dma_addr_t rx_buf_dma_phys;
dma_addr_t tx_buf_dma_phys;
unsigned int uart_base;
/*
* Buffer for rx dma.It is not required for tx because the buffer
* comes from port structure.
*/
unsigned char *rx_buf;
unsigned int prev_rx_dma_pos;
int tx_buf_size;
int tx_dma_used;
int rx_dma_used;
spinlock_t tx_lock;
spinlock_t rx_lock;
/* timer to poll activity on rx dma */
struct timer_list rx_timer;
int rx_buf_size;
int rx_timeout;
};
struct uart_omap_port {
struct uart_port port;
struct uart_omap_dma uart_dma;
struct platform_device *pdev;
unsigned char ier;
unsigned char lcr;
unsigned char mcr;
unsigned char fcr;
unsigned char efr;
int use_dma;
/*
* Some bits in registers are cleared on a read, so they must
* be saved whenever the register is read but the bits will not
* be immediately processed.
*/
unsigned int lsr_break_flag;
unsigned char msr_saved_flags;
char name[20];
unsigned long port_activity;
};
#endif /* __OMAP_SERIAL_H__ */

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@ -1416,6 +1416,33 @@ config SERIAL_OF_PLATFORM
Currently, only 8250 compatible ports are supported, but
others can easily be added.
config SERIAL_OMAP
tristate "OMAP serial port support"
depends on ARCH_OMAP2 || ARCH_OMAP3 || ARCH_OMAP4
select SERIAL_CORE
help
If you have a machine based on an Texas Instruments OMAP CPU you
can enable its onboard serial ports by enabling this option.
By enabling this option you take advantage of dma feature available
with the omap-serial driver. DMA support can be enabled from platform
data.
config SERIAL_OMAP_CONSOLE
bool "Console on OMAP serial port"
depends on SERIAL_OMAP
select SERIAL_CORE_CONSOLE
help
Select this option if you would like to use omap serial port as
console.
Even if you say Y here, the currently visible virtual console
(/dev/tty0) will still be used as the system console by default, but
you can alter that using a kernel command line option such as
"console=ttyOx". (Try "man bootparam" or see the documentation of
your boot loader about how to pass options to the kernel at
boot time.)
config SERIAL_OF_PLATFORM_NWPSERIAL
tristate "NWP serial port driver"
depends on PPC_OF && PPC_DCR

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@ -88,3 +88,4 @@ obj-$(CONFIG_SERIAL_ALTERA_JTAGUART) += altera_jtaguart.o
obj-$(CONFIG_SERIAL_ALTERA_UART) += altera_uart.o
obj-$(CONFIG_SERIAL_MRST_MAX3110) += mrst_max3110.o
obj-$(CONFIG_SERIAL_MFD_HSU) += mfd.o
obj-$(CONFIG_SERIAL_OMAP) += omap-serial.o

1333
drivers/serial/omap-serial.c Normal file

File diff suppressed because it is too large Load diff

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@ -196,6 +196,9 @@
/* High Speed UART for Medfield */
#define PORT_MFD 95
/* TI OMAP-UART */
#define PORT_OMAP 96
#ifdef __KERNEL__
#include <linux/compiler.h>