u-boot/arch/arm/mach-imx/i2c-mxv7.c
Tom Rini 83d290c56f SPDX: Convert all of our single license tags to Linux Kernel style
When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>
2018-05-07 09:34:12 -04:00

117 lines
2.4 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2012 Boundary Devices Inc.
*/
#include <common.h>
#include <malloc.h>
#include <asm/arch/clock.h>
#include <asm/arch/imx-regs.h>
#include <linux/errno.h>
#include <asm/gpio.h>
#include <asm/mach-imx/mxc_i2c.h>
#include <watchdog.h>
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
#ifdef I2C4_BASE_ADDR
(void *)I2C4_BASE_ADDR,
#endif
};
/* i2c_index can be from 0 - 3 */
int setup_i2c(unsigned i2c_index, int speed, int slave_addr,
struct i2c_pads_info *p)
{
char name[9];
int ret;
if (i2c_index >= ARRAY_SIZE(i2c_bases))
return -EINVAL;
snprintf(name, sizeof(name), "i2c_sda%01d", i2c_index);
ret = gpio_request(p->sda.gp, name);
if (ret)
return ret;
snprintf(name, sizeof(name), "i2c_scl%01d", i2c_index);
ret = gpio_request(p->scl.gp, name);
if (ret)
goto err_req;
/* Enable i2c clock */
ret = enable_i2c_clk(1, i2c_index);
if (ret)
goto err_clk;
/* Make sure bus is idle */
ret = force_idle_bus(p);
if (ret)
goto err_idle;
#ifndef CONFIG_DM_I2C
bus_i2c_init(i2c_index, speed, slave_addr, force_idle_bus, p);
#endif
return 0;
err_idle:
err_clk:
gpio_free(p->scl.gp);
err_req:
gpio_free(p->sda.gp);
return ret;
}