/*
* This module shows how to create a simple subdirectory in sysfs called
* /sys/kernel/kobject-example In that directory, 3 files are created:
* "foo", "baz", and "bar". If an integer is written to these files, it can be
* later read out of it.
*/
static int foo;
/*
* The "foo" file where a static variable is read from and written to.
*/
static struct msm_gpio qup_i2c_gpios_io[] = {
{ GPIO_CFG(60, 0, GPIO_CFG_OUTPUT, GPIO_CFG_NO_PULL, GPIO_CFG_8MA),
"qup_scl" },
{ GPIO_CFG(61, 0, GPIO_CFG_INPUT, GPIO_CFG_NO_PULL, GPIO_CFG_8MA),
"qup_sda" },
{ GPIO_CFG(131, 0, GPIO_CFG_OUTPUT, GPIO_CFG_NO_PULL, GPIO_CFG_8MA),
"qup_scl" },
{ GPIO_CFG(132, 0, GPIO_CFG_INPUT, GPIO_CFG_NO_PULL, GPIO_CFG_8MA),
"qup_sda" },
};
static struct msm_gpio qup_i2c_gpios_hw[] = {
{ GPIO_CFG(60, 1, GPIO_CFG_INPUT, GPIO_CFG_NO_PULL, GPIO_CFG_8MA),
"qup_scl" },
{ GPIO_CFG(61, 1, GPIO_CFG_INPUT, GPIO_CFG_NO_PULL, GPIO_CFG_8MA),
"qup_sda" },
{ GPIO_CFG(131, 2, GPIO_CFG_INPUT, GPIO_CFG_NO_PULL, GPIO_CFG_8MA),
"qup_scl" },
{ GPIO_CFG(132, 2, GPIO_CFG_INPUT, GPIO_CFG_NO_PULL, GPIO_CFG_8MA),
"qup_sda" },
};
static void gsbi_qup_i2c_gpio_config(int adap_id, int config_type)
{
int rc;
if (adap_id < 0 || adap_id > 1)
return;
/* Each adapter gets 2 lines from the table */
if (config_type)
rc = msm_gpios_enable(&qup_i2c_gpios_hw[adap_id*2], 2);
else
rc = msm_gpios_enable(&qup_i2c_gpios_io[adap_id*2], 2);
if (rc < 0)
pr_err("QUP GPIO request/enable failed: %d\n", rc);
}
static ssize_t foo_show(struct kobject *kobj, struct kobj_attribute *attr,
char *buf)
{
return sprintf(buf, "%d\n", foo);
}
static ssize_t foo_store(struct kobject *kobj, struct kobj_attribute *attr,
const char *buf, size_t count)
{
int sda,scl;
int i;
sscanf(buf, "%du", &foo);
printk("foo = %d.\n",foo);
foo = foo -1;
if (foo < 0 || foo > 1)
{
printk("input foo error. foo=%d.\n",foo);
return 0;
}
sda = GPIO_PIN((&qup_i2c_gpios_hw[foo*2+1])->gpio_cfg);
scl = GPIO_PIN((&qup_i2c_gpios_hw[foo*2])->gpio_cfg);
printk("sda = %d.\n",sda);
printk("scl = %d.\n",scl);
gsbi_qup_i2c_gpio_config(foo,0);
for(i=0;i<9;i++)
{
if(gpio_get_value(sda))
{
printk("sda of i2c%d is high when %d pulse is output on scl.\n",foo,i);
break;
}
gpio_set_value(scl,0);
udelay(5);
gpio_set_value(scl,1);
udelay(5);
}
gsbi_qup_i2c_gpio_config(foo,1);
printk("finish.\n");
return count;
}
static struct kobj_attribute foo_attribute =
__ATTR(i2c_unlock, 0666, foo_show, foo_store);
/*
* Create a group of attributes so that we can create and destroy them all
* at once.
*/
static struct attribute *attrs[] = {
&foo_attribute.attr,
NULL,? /* need to NULL terminate the list of attributes */
};
/*
* An unnamed attribute group will put all of the attributes directly in
* the kobject directory. If we specify a name, a subdirectory will be
* created for the attributes with the directory being the name of the
* attribute group.
*/
static struct attribute_group attr_group = {
.attrs = attrs,
};
static struct kobject *example_kobj;
static int __init example_init(void)
{
int retval;
/*
* Create a simple kobject with the name of "kobject_example",
* located under /sys/kernel/
*
* As this is a simple directory, no uevent will be sent to
* userspace. That is why this function should not be used for
* any type of dynamic kobjects, where the name and number are
* not known ahead of time.
*/
example_kobj = kobject_create_and_add("i2c_recovery", kernel_kobj);
if (!example_kobj)
return -ENOMEM;
/* Create the files associated with this kobject */
retval = sysfs_create_group(example_kobj, &attr_group);
if (retval)
kobject_put(example_kobj);
return retval;
}
static void __exit example_exit(void)
{
kobject_put(example_kobj);
}
module_init(example_init);
module_exit(example_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Wupeng");
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