[ARM] OpenRD: Enable SD/UART selection for serial port 1

This patch enables users to choose either the SDIO interface or UART1
(RS232/RS485). The selection can be done through kernel parameter.

By default the port would be used for SDIO interface. Passing the string
"kw_openrd_init_uart1=232" or "kw_openrd_init_uart1=485" enables either
the RS-232 or RS-485 port respectively; disabling the SDIO interface.
Anything else selects the default SDIO interface.

"kw_openrd_init_uart1=485" is ignored on OpenRD-Base as it doesn't
have RS485 port.

Signed-off-by: Tanmay Upadhyay <tanmay.upadhyay@einfochips.com>
Acked-by: Alexander Clouter <alex@digriz.org.uk>
Signed-off-by: Nicolas Pitre <nico@fluxnic.net>
This commit is contained in:
Tanmay Upadhyay 2010-08-26 11:11:58 +05:30 committed by Nicolas Pitre
parent f539dfedbd
commit fd2ce9c59a

View File

@ -16,6 +16,7 @@
#include <linux/ata_platform.h>
#include <linux/mv643xx_eth.h>
#include <linux/i2c.h>
#include <linux/gpio.h>
#include <asm/mach-types.h>
#include <asm/mach/arch.h>
#include <mach/kirkwood.h>
@ -57,7 +58,22 @@ static struct mvsdio_platform_data openrd_mvsdio_data = {
};
static unsigned int openrd_mpp_config[] __initdata = {
MPP12_SD_CLK,
MPP13_SD_CMD,
MPP14_SD_D0,
MPP15_SD_D1,
MPP16_SD_D2,
MPP17_SD_D3,
MPP28_GPIO,
MPP29_GPIO,
MPP34_GPIO,
0
};
/* Configure MPP for UART1 */
static unsigned int openrd_uart1_mpp_config[] __initdata = {
MPP13_UART1_TXD,
MPP14_UART1_RXD,
0
};
@ -67,6 +83,68 @@ static struct i2c_board_info i2c_board_info[] __initdata = {
},
};
static int __initdata uart1;
static int __init sd_uart_selection(char *str)
{
uart1 = -EINVAL;
/* Default is SD. Change if required, for UART */
if (!str)
return 0;
if (!strncmp(str, "232", 3)) {
uart1 = 232;
} else if (!strncmp(str, "485", 3)) {
/* OpenRD-Base doesn't have RS485. Treat is as an
* unknown argument & just have default setting -
* which is SD */
if (machine_is_openrd_base()) {
uart1 = -ENODEV;
return 1;
}
uart1 = 485;
}
return 1;
}
/* Parse boot_command_line string kw_openrd_init_uart1=232/485 */
__setup("kw_openrd_init_uart1=", sd_uart_selection);
static int __init uart1_mpp_config(void)
{
kirkwood_mpp_conf(openrd_uart1_mpp_config);
if (gpio_request(34, "SD_UART1_SEL")) {
printk(KERN_ERR "GPIO request failed for SD/UART1 selection"
", gpio: 34\n");
return -EIO;
}
if (gpio_request(28, "RS232_RS485_SEL")) {
printk(KERN_ERR "GPIO request failed for RS232/RS485 selection"
", gpio# 28\n");
gpio_free(34);
return -EIO;
}
/* Select UART1
* Pin # 34: 0 => UART1, 1 => SD */
gpio_direction_output(34, 0);
/* Select RS232 OR RS485
* Pin # 28: 0 => RS232, 1 => RS485 */
if (uart1 == 232)
gpio_direction_output(28, 0);
else
gpio_direction_output(28, 1);
gpio_free(34);
gpio_free(28);
return 0;
}
static void __init openrd_init(void)
{
/*
@ -90,7 +168,6 @@ static void __init openrd_init(void)
kirkwood_ge01_init(&openrd_ge01_data);
kirkwood_sata_init(&openrd_sata_data);
kirkwood_sdio_init(&openrd_mvsdio_data);
kirkwood_i2c_init();
@ -99,6 +176,28 @@ static void __init openrd_init(void)
ARRAY_SIZE(i2c_board_info));
kirkwood_audio_init();
}
if (uart1 <= 0) {
if (uart1 < 0)
printk(KERN_ERR "Invalid kernel parameter to select "
"UART1. Defaulting to SD. ERROR CODE: %d\n",
uart1);
/* Select SD
* Pin # 34: 0 => UART1, 1 => SD */
if (gpio_request(34, "SD_UART1_SEL")) {
printk(KERN_ERR "GPIO request failed for SD/UART1 "
"selection, gpio: 34\n");
} else {
gpio_direction_output(34, 1);
gpio_free(34);
kirkwood_sdio_init(&openrd_mvsdio_data);
}
} else {
if (!uart1_mpp_config())
kirkwood_uart1_init();
}
}
static int __init openrd_pci_init(void)