amba pl011: platform data for reg lockup and glitch v2

This patch provides platform data for following
 - uart reset function to assist uart register lockup workaround

 - init/exit function to fix glitch in the tx pin in tty_open
	when tty port0 is opened a glitch is seen in the tx line
	of uart0. This happens in pl011_startup() when tx fifo
	interrupt is provoked into asserting.
	Now uart0 pins are enabled (alt function) only when init
	is complete and turned back to gpio when closed.

Signed-off-by: Shreshtha Kumar Sahu <shreshthakumar.sahu@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Shreshtha Kumar Sahu 2011-06-13 10:11:44 +02:00 committed by Greg Kroah-Hartman
parent c16d51a32b
commit 1a7d4369b3
2 changed files with 66 additions and 4 deletions

View File

@ -110,10 +110,18 @@ static pin_cfg_t mop500_pins_common[] = {
GPIO168_KP_O0,
/* UART */
GPIO0_U0_CTSn | PIN_INPUT_PULLUP,
GPIO1_U0_RTSn | PIN_OUTPUT_HIGH,
GPIO2_U0_RXD | PIN_INPUT_PULLUP,
GPIO3_U0_TXD | PIN_OUTPUT_HIGH,
/* uart-0 pins gpio configuration should be
* kept intact to prevent glitch in tx line
* when tty dev is opened. Later these pins
* are configured to uart mop500_pins_uart0
*
* It will be replaced with uart configuration
* once the issue is solved.
*/
GPIO0_GPIO | PIN_INPUT_PULLUP,
GPIO1_GPIO | PIN_OUTPUT_HIGH,
GPIO2_GPIO | PIN_INPUT_PULLUP,
GPIO3_GPIO | PIN_OUTPUT_HIGH,
GPIO29_U2_RXD | PIN_INPUT_PULLUP,
GPIO30_U2_TXD | PIN_OUTPUT_HIGH,

View File

@ -27,18 +27,21 @@
#include <linux/leds-lp5521.h>
#include <linux/input.h>
#include <linux/gpio_keys.h>
#include <linux/delay.h>
#include <asm/mach-types.h>
#include <asm/mach/arch.h>
#include <plat/i2c.h>
#include <plat/ste_dma40.h>
#include <plat/pincfg.h>
#include <mach/hardware.h>
#include <mach/setup.h>
#include <mach/devices.h>
#include <mach/irqs.h>
#include "pins-db8500.h"
#include "ste-dma40-db8500.h"
#include "devices-db8500.h"
#include "board-mop500.h"
@ -393,12 +396,63 @@ static struct stedma40_chan_cfg uart2_dma_cfg_tx = {
};
#endif
static pin_cfg_t mop500_pins_uart0[] = {
GPIO0_U0_CTSn | PIN_INPUT_PULLUP,
GPIO1_U0_RTSn | PIN_OUTPUT_HIGH,
GPIO2_U0_RXD | PIN_INPUT_PULLUP,
GPIO3_U0_TXD | PIN_OUTPUT_HIGH,
};
#define PRCC_K_SOFTRST_SET 0x18
#define PRCC_K_SOFTRST_CLEAR 0x1C
static void ux500_uart0_reset(void)
{
void __iomem *prcc_rst_set, *prcc_rst_clr;
prcc_rst_set = (void __iomem *)IO_ADDRESS(U8500_CLKRST1_BASE +
PRCC_K_SOFTRST_SET);
prcc_rst_clr = (void __iomem *)IO_ADDRESS(U8500_CLKRST1_BASE +
PRCC_K_SOFTRST_CLEAR);
/* Activate soft reset PRCC_K_SOFTRST_CLEAR */
writel((readl(prcc_rst_clr) | 0x1), prcc_rst_clr);
udelay(1);
/* Release soft reset PRCC_K_SOFTRST_SET */
writel((readl(prcc_rst_set) | 0x1), prcc_rst_set);
udelay(1);
}
static void ux500_uart0_init(void)
{
int ret;
ret = nmk_config_pins(mop500_pins_uart0,
ARRAY_SIZE(mop500_pins_uart0));
if (ret < 0)
pr_err("pl011: uart pins_enable failed\n");
}
static void ux500_uart0_exit(void)
{
int ret;
ret = nmk_config_pins_sleep(mop500_pins_uart0,
ARRAY_SIZE(mop500_pins_uart0));
if (ret < 0)
pr_err("pl011: uart pins_disable failed\n");
}
static struct amba_pl011_data uart0_plat = {
#ifdef CONFIG_STE_DMA40
.dma_filter = stedma40_filter,
.dma_rx_param = &uart0_dma_cfg_rx,
.dma_tx_param = &uart0_dma_cfg_tx,
#endif
.init = ux500_uart0_init,
.exit = ux500_uart0_exit,
.reset = ux500_uart0_reset,
};
static struct amba_pl011_data uart1_plat = {