Commit cc54a0f7 authored by Troy Kisky's avatar Troy Kisky Committed by Heiko Schocher
Browse files

imx-common: add i2c.c for bus recovery support


Signed-off-by: default avatarTroy Kisky <troy.kisky@boundarydevices.com>
parent df369dcd
......@@ -27,7 +27,9 @@ include $(TOPDIR)/config.mk
LIB = $(obj)libimx-common.o
COBJS = iomux-v3.o timer.o cpu.o speed.o
COBJS-y = iomux-v3.o timer.o cpu.o speed.o
COBJS-$(CONFIG_I2C_MXC) += i2c.o
COBJS := $(sort $(COBJS-y))
SRCS := $(SOBJS:.o=.S) $(COBJS:.o=.c)
OBJS := $(addprefix $(obj),$(SOBJS) $(COBJS))
......
/*
* Copyright (C) 2012 Boundary Devices Inc.
*
* See file CREDITS for list of people who contributed to this
* project.
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
#include <common.h>
#include <asm/arch/clock.h>
#include <asm/arch/imx-regs.h>
#include <asm/errno.h>
#include <asm/gpio.h>
#include <asm/imx-common/mxc_i2c.h>
#include <watchdog.h>
static int force_idle_bus(void *priv)
{
int i;
int sda, scl;
ulong elapsed, start_time;
struct i2c_pads_info *p = (struct i2c_pads_info *)priv;
int ret = 0;
gpio_direction_input(p->sda.gp);
gpio_direction_input(p->scl.gp);
imx_iomux_v3_setup_pad(p->sda.gpio_mode);
imx_iomux_v3_setup_pad(p->scl.gpio_mode);
sda = gpio_get_value(p->sda.gp);
scl = gpio_get_value(p->scl.gp);
if ((sda & scl) == 1)
goto exit; /* Bus is idle already */
printf("%s: sda=%d scl=%d sda.gp=0x%x scl.gp=0x%x\n", __func__,
sda, scl, p->sda.gp, p->scl.gp);
/* Send high and low on the SCL line */
for (i = 0; i < 9; i++) {
gpio_direction_output(p->scl.gp, 0);
udelay(50);
gpio_direction_input(p->scl.gp);
udelay(50);
}
start_time = get_timer(0);
for (;;) {
sda = gpio_get_value(p->sda.gp);
scl = gpio_get_value(p->scl.gp);
if ((sda & scl) == 1)
break;
WATCHDOG_RESET();
elapsed = get_timer(start_time);
if (elapsed > (CONFIG_SYS_HZ / 5)) { /* .2 seconds */
ret = -EBUSY;
printf("%s: failed to clear bus, sda=%d scl=%d\n",
__func__, sda, scl);
break;
}
}
exit:
imx_iomux_v3_setup_pad(p->sda.i2c_mode);
imx_iomux_v3_setup_pad(p->scl.i2c_mode);
return ret;
}
static void * const i2c_bases[] = {
(void *)I2C1_BASE_ADDR,
(void *)I2C2_BASE_ADDR,
#ifdef I2C3_BASE_ADDR
(void *)I2C3_BASE_ADDR,
#endif
};
/* i2c_index can be from 0 - 2 */
void setup_i2c(unsigned i2c_index, int speed, int slave_addr,
struct i2c_pads_info *p)
{
if (i2c_index >= ARRAY_SIZE(i2c_bases))
return;
/* Enable i2c clock */
enable_i2c_clk(1, i2c_index);
/* Make sure bus is idle */
force_idle_bus(p);
bus_i2c_init(i2c_bases[i2c_index], speed, slave_addr,
force_idle_bus, p);
}
......@@ -117,6 +117,26 @@ void enable_usboh3_clk(unsigned char enable)
writel(reg, &mxc_ccm->CCGR2);
}
#ifdef CONFIG_I2C_MXC
/* i2c_num can be from 0 - 2 */
int enable_i2c_clk(unsigned char enable, unsigned i2c_num)
{
u32 reg;
u32 mask;
if (i2c_num > 2)
return -EINVAL;
mask = MXC_CCM_CCGR_CG_MASK << ((i2c_num + 9) << 1);
reg = __raw_readl(&mxc_ccm->CCGR1);
if (enable)
reg |= mask;
else
reg &= ~mask;
__raw_writel(reg, &mxc_ccm->CCGR1);
return 0;
}
#endif
void set_usb_phy1_clk(void)
{
unsigned int reg;
......
......@@ -50,6 +50,26 @@ void enable_usboh3_clk(unsigned char enable)
}
#ifdef CONFIG_I2C_MXC
/* i2c_num can be from 0 - 2 */
int enable_i2c_clk(unsigned char enable, unsigned i2c_num)
{
u32 reg;
u32 mask;
if (i2c_num > 2)
return -EINVAL;
mask = MXC_CCM_CCGR_CG_MASK << ((i2c_num + 3) << 1);
reg = __raw_readl(&imx_ccm->CCGR2);
if (enable)
reg |= mask;
else
reg &= ~mask;
__raw_writel(reg, &imx_ccm->CCGR2);
return 0;
}
#endif
static u32 decode_pll(enum pll_clocks pll, u32 infreq)
{
u32 div;
......
......@@ -49,5 +49,6 @@ void enable_usb_phy2_clk(unsigned char enable);
void set_usboh3_clk(void);
void enable_usboh3_clk(unsigned char enable);
void mxc_set_sata_internal_clock(void);
int enable_i2c_clk(unsigned char enable, unsigned i2c_num);
#endif /* __ASM_ARCH_CLOCK_H */
......@@ -48,5 +48,6 @@ u32 imx_get_fecclk(void);
unsigned int mxc_get_clock(enum mxc_clock clk);
void enable_usboh3_clk(unsigned char enable);
int enable_sata_clock(void);
int enable_i2c_clk(unsigned char enable, unsigned i2c_num);
#endif /* __ASM_ARCH_CLOCK_H */
/*
* Copyright (C) 2011 Freescale Semiconductor, Inc. All Rights Reserved.
*
* 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.
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#ifndef __ASM_ARCH_MXC_MXC_I2C_H__
#define __ASM_ARCH_MXC_MXC_I2C_H__
#include <asm/imx-common/iomux-v3.h>
struct i2c_pin_ctrl {
iomux_v3_cfg_t i2c_mode;
iomux_v3_cfg_t gpio_mode;
unsigned char gp;
unsigned char spare;
};
struct i2c_pads_info {
struct i2c_pin_ctrl scl;
struct i2c_pin_ctrl sda;
};
void setup_i2c(unsigned i2c_index, int speed, int slave_addr,
struct i2c_pads_info *p);
void bus_i2c_init(void *base, int speed, int slave_addr,
int (*idle_bus_fn)(void *p), void *p);
int bus_i2c_read(void *base, uchar chip, uint addr, int alen, uchar *buf,
int len);
int bus_i2c_write(void *base, uchar chip, uint addr, int alen,
const uchar *buf, int len);
#endif
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