[PATCH v3] OpenRD: Enable SD/UART selection for serial port 1

Tanmay Upadhyay
2010-08-11T05:21:02Z

This patch enables user to use serial port 1 of the OpenRD device for SDIO
or UART(RS232/RS485). The selection can be done through kernel parameter.

By default the port would be used for SDIO. To select RS232 or RS485 mode,
pass string "uart=232" or "uart=485" respectively in the kernel parameters.
"uart=485" is ignored on OpenRD-Base as it doesn't have RS485 port.

Signed-off-by: Tanmay Upadhyay <tanmay.upadhyay@einfochips.com>
---
arch/arm/mach-kirkwood/openrd-setup.c | 101 ++++++++++++++++++++++++++++++++-
1 files changed, 100 insertions(+), 1 deletions(-)

diff --git a/arch/arm/mach-kirkwood/openrd-setup.c b/arch/arm/mach-kirkwood/openrd-setup.c
index fd06be6..46378c0 100644
--- a/arch/arm/mach-kirkwood/openrd-setup.c
+++ b/arch/arm/mach-kirkwood/openrd-setup.c
@@ -19,6 +19,7 @@
#include <asm/mach-types.h>
#include <asm/mach/arch.h>
#include <mach/kirkwood.h>
+#include <mach/gpio.h>
#include <plat/mvsdio.h>
#include "common.h"
#include "mpp.h"
@@ -57,7 +58,15 @@ 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
};

@@ -67,6 +76,75 @@ 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 uart=232/485 */
+__setup("uart=", sd_uart_selection);
+
+static int __init uart1_mpp_config(void)
+{
+ /* Configure MPP for UART1 */
+ unsigned int uart1_mpp_config[] = {
+ MPP13_UART1_TXD,
+ MPP14_UART1_RXD,
+ 0
+ };
+
+ kirkwood_mpp_conf(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)
--
1.6.6.1