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pwm-sunxi.c
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pwm-sunxi.c
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/* pwm-sunxi.c
*
* pwm module for sun4i (and others) like cubieboard and pcduino
*
* (C) Copyright 2013
* David H. Wilkins <dwilkins@conecuh.com>
*
* 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 <linux/kobject.h>
#include <linux/slab.h>
#include <linux/device.h>
#include <linux/sysfs.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/err.h>
#include <asm/io.h>
#include <asm/delay.h>
#include <mach/platform.h>
#include <linux/pwm.h>
#include <linux/ctype.h>
#include <linux/limits.h>
#include <pwm-sunxi.h>
#include <linux/pwm.h>
#include <linux/kdev_t.h>
/*
* Forward Declarations
*/
void pwm_dump_pwm_ctrl_reg(struct sun4i_pwm_ctrl *pwm, struct sun4i_pwm_ctrl *pwm_compare,const char *name);
void pwm_dump_pwm_period_reg(struct sun4i_pwm_period *period, struct sun4i_pwm_period *period_compare,const char *name);
void pwm_dump_ioreg_cfg(struct sun4i_ioreg_cfg0 *cfg,struct sun4i_ioreg_cfg0 *cfg_compare, const char *name);
void release_pwm_sunxi(struct kobject *kobj);
void pwm_setup_available_channels(void );
ssize_t pwm_set_mode(unsigned int enable, struct sun4i_pwm_available_channel *chan);
enum sun4i_pwm_prescale pwm_get_best_prescale(unsigned long long period);
unsigned int get_entire_cycles(struct sun4i_pwm_available_channel *chan);
unsigned int get_active_cycles(struct sun4i_pwm_available_channel *chan);
unsigned long convert_string_to_microseconds(const char *buf);
int pwm_set_period_and_duty(struct sun4i_pwm_available_channel *chan);
void fixup_duty(struct sun4i_pwm_available_channel *chan);
static DEFINE_MUTEX(sysfs_lock);
static struct class pwm_class;
struct kobject *pwm0_kobj;
struct kobject *pwm1_kobj;
void *PWM_CTRL_REG_BASE = NULL;
static struct class_attribute pwm_class_attrs[] = {
__ATTR_NULL
};
static struct class pwm_class = {
.name = "pwm-sunxi",
.owner = THIS_MODULE,
.class_attrs = pwm_class_attrs,
};
/*
* sysfs store / show functions
*/
static ssize_t pwm_polarity_show(struct device *dev, struct device_attribute *attr, char *buf);
static ssize_t pwm_period_show(struct device *dev, struct device_attribute *attr, char *buf);
static ssize_t pwm_duty_show(struct device *dev, struct device_attribute *attr, char *buf);
static ssize_t pwm_run_show(struct device *dev,struct device_attribute *attr, char *buf);
static ssize_t pwm_duty_percent_show(struct device *dev,struct device_attribute *attr, char *buf);
static ssize_t pwm_pulse_show(struct device *dev,struct device_attribute *attr, char *buf);
static ssize_t pwm_pin_show(struct device *dev,struct device_attribute *attr, char *buf);
static ssize_t pwm_polarity_store(struct device *dev,struct device_attribute *attr, const char *buf, size_t size);
static ssize_t pwm_period_store(struct device *dev,struct device_attribute *attr, const char *buf, size_t size);
static ssize_t pwm_duty_store(struct device *dev,struct device_attribute *attr, const char *buf, size_t size);
static ssize_t pwm_run_store(struct device *dev,struct device_attribute *attr, const char *buf, size_t size);
static ssize_t pwm_duty_percent_store(struct device *dev,struct device_attribute *attr, const char *buf, size_t size);
static ssize_t pwm_pulse_store(struct device *dev,struct device_attribute *attr, const char *buf, size_t size);
static DEVICE_ATTR(polarity, 0644,pwm_polarity_show, pwm_polarity_store);
static DEVICE_ATTR(period, 0644, pwm_period_show, pwm_period_store);
static DEVICE_ATTR(duty, 0644,pwm_duty_show, pwm_duty_store);
static DEVICE_ATTR(run, 0644, pwm_run_show, pwm_run_store);
static DEVICE_ATTR(duty_percent, 0644, pwm_duty_percent_show, pwm_duty_percent_store);
static DEVICE_ATTR(pulse, 0644, pwm_pulse_show, pwm_pulse_store);
static DEVICE_ATTR(pin, 0644, pwm_pin_show, NULL);
static const struct attribute *pwm_attrs[] = {
&dev_attr_polarity.attr,
&dev_attr_period.attr,
&dev_attr_duty.attr,
&dev_attr_run.attr,
&dev_attr_duty_percent.attr,
&dev_attr_pulse.attr,
&dev_attr_pin.attr,
NULL,
};
static const struct attribute_group pwm_attr_group = {
.attrs = (struct attribute **) pwm_attrs
};
struct device *pwm0;
struct device *pwm1;
static struct sun4i_pwm_available_channel pwm_available_chan[SUN4I_MAX_HARDWARE_PWM_CHANNELS];
static int __init sunxi_pwm_init(void)
{
int return_val;
return_val = class_register(&pwm_class);
if(return_val) {
class_unregister(&pwm_class);
}
pwm0 = device_create(&pwm_class,NULL,MKDEV(0,0),&pwm_available_chan[0],"pwm0");
pwm1 = device_create(&pwm_class,NULL,MKDEV(0,0),&pwm_available_chan[1],"pwm1");
pwm0_kobj = &pwm0->kobj;
pwm1_kobj = &pwm1->kobj;
return_val = sysfs_create_group(pwm0_kobj,&pwm_attr_group);
return_val = sysfs_create_group(pwm1_kobj,&pwm_attr_group);
pwm_setup_available_channels();
printk(KERN_INFO "pwm-sunxi: Initialized...");
return return_val;
}
void sunxi_pwm_exit(void)
{
union sun4i_pwm_ctrl_u ch0;
ch0.initializer = readl(pwm_available_chan[0].ctrl_addr);
ch0.s.ch0_en = ch0.s.ch1_en = 0;
writel(0,pwm_available_chan[0].ctrl_addr);
/*
writel(pwm_available_chan[0].period_reg_backup.initializer,pwm_available_chan[0].period_reg_addr );
writel(pwm_available_chan[1].period_reg_backup.initializer,pwm_available_chan[1].period_reg_addr );
*/
writel(0,pwm_available_chan[0].period_reg_addr );
writel(0,pwm_available_chan[1].period_reg_addr );
writel(pwm_available_chan[0].pin_backup.initializer, pwm_available_chan[0].pin_addr);
writel(pwm_available_chan[1].pin_backup.initializer, pwm_available_chan[1].pin_addr);
device_destroy(&pwm_class,pwm0->devt);
device_destroy(&pwm_class,pwm1->devt);
class_unregister(&pwm_class);
}
/*
* Functions to display the pwm variables currently set
*/
static ssize_t pwm_polarity_show(struct device *dev, struct device_attribute *attr, char *buf) {
const struct sun4i_pwm_available_channel *chan = dev_get_drvdata(dev);
ssize_t status;
switch (chan->channel) {
case 0:
status = scnprintf(buf,PAGE_SIZE,"%d",chan->ctrl_current.s.ch0_act_state);
break;
case 1:
status = scnprintf(buf,PAGE_SIZE,"%d",chan->ctrl_current.s.ch1_act_state);
break;
default:
status = -EINVAL;
break;
}
return status;
}
static ssize_t pwm_period_show(struct device *dev, struct device_attribute *attr, char *buf) {
const struct sun4i_pwm_available_channel *chan = dev_get_drvdata(dev);
ssize_t status;
status = sprintf(buf,"%lu",chan->period);
return status;
}
static ssize_t pwm_duty_show(struct device *dev, struct device_attribute *attr, char *buf) {
const struct sun4i_pwm_available_channel *chan = dev_get_drvdata(dev);
ssize_t status;
status = sprintf(buf,"%lu",chan->duty);
return status;
}
static ssize_t pwm_run_show(struct device *dev,struct device_attribute *attr, char *buf) {
const struct sun4i_pwm_available_channel *chan = dev_get_drvdata(dev);
ssize_t status;
switch (chan->channel) {
case 0:
status = sprintf(buf,"%d",chan->ctrl_current.s.ch0_en);
break;
case 1:
status = sprintf(buf,"%d",chan->ctrl_current.s.ch1_en);
break;
default:
status = -EINVAL;
break;
}
return status;
}
static ssize_t pwm_duty_percent_show(struct device *dev,struct device_attribute *attr, char *buf) {
const struct sun4i_pwm_available_channel *chan = dev_get_drvdata(dev);
if(chan->duty_percent >= 0) {
return sprintf(buf,"%u",chan->duty_percent);
} else {
sprintf(buf,"N/A");
return -EINVAL;
}
}
static ssize_t pwm_pulse_show(struct device *dev,struct device_attribute *attr, char *buf) {
const struct sun4i_pwm_available_channel *chan = dev_get_drvdata(dev);
ssize_t status;
switch (chan->channel) {
case 0:
status = sprintf(buf,"%d",chan->ctrl_current.s.ch0_pulse_start);
break;
case 1:
status = sprintf(buf,"%d",chan->ctrl_current.s.ch1_pulse_start);
break;
default:
status = -EINVAL;
break;
}
return status;
}
static ssize_t pwm_pin_show(struct device *dev,struct device_attribute *attr, char *buf) {
const struct sun4i_pwm_available_channel *chan = dev_get_drvdata(dev);
ssize_t status;
status = sprintf(buf,"%s",chan->pin_name);
return status;
}
/*
* Functions to store values for pwm
*/
static ssize_t pwm_polarity_store(struct device *dev,struct device_attribute *attr, const char *buf, size_t size) {
struct sun4i_pwm_available_channel *chan = dev_get_drvdata(dev);
ssize_t status = -EINVAL;
int act_state = 0;
sscanf(buf,"%d",&act_state);
if(act_state < 2) {
switch (chan->channel) {
case 0:
chan->ctrl_backup.initializer = chan->ctrl_current.initializer;
chan->ctrl_current.initializer = readl(chan->ctrl_addr);
chan->ctrl_current.s.ch0_act_state = act_state;
writel(chan->ctrl_current.initializer,chan->ctrl_addr);
break;
case 1:
chan->ctrl_backup.initializer = chan->ctrl_current.initializer;
chan->ctrl_current.initializer = readl(chan->ctrl_addr);
chan->ctrl_current.s.ch1_act_state = act_state;
writel(chan->ctrl_current.initializer,chan->ctrl_addr);
break;
default:
status = -EINVAL;
break;
}
status = size;
}
return status;
}
static ssize_t pwm_period_store(struct device *dev,struct device_attribute *attr, const char *buf, size_t size) {
unsigned long long period = 0;
struct sun4i_pwm_available_channel *chan = dev_get_drvdata(dev);
enum sun4i_pwm_prescale new_prescale = 0;
period = convert_string_to_microseconds(buf);
new_prescale = pwm_get_best_prescale(period);
if(!period || period > ULONG_MAX || new_prescale == -EINVAL) {
new_prescale = chan->prescale;
period = chan->period;
size = -EINVAL;
}
if(period <= chan->duty) {
chan->duty = period;
}
chan->period = period;
chan->prescale = new_prescale;
fixup_duty(chan);
if(chan->duty) {
pwm_set_mode(NO_ENABLE_CHANGE,chan);
}
return size;
}
static ssize_t pwm_duty_store(struct device *dev,struct device_attribute *attr, const char *buf, size_t size) {
unsigned long long duty = 0;
struct sun4i_pwm_available_channel *chan = dev_get_drvdata(dev);
duty = convert_string_to_microseconds(buf);
duty = duty > ULONG_MAX ? ULONG_MAX : duty;
duty = duty > chan->period ? chan->period : duty;
chan->duty_percent = -1; /* disable duty_percent if duty is set by hand */
chan->duty = duty;
pwm_set_period_and_duty(chan);
return size;
}
struct time_suffix suffixes[] = {
[0] = { .suffix = "hz", .multiplier = 1, .freq = true }, /* f = 1/T */
[1] = { .suffix = "khz", .multiplier = 1000, .freq = true },
[2] = { .suffix = "mhz", .multiplier = 1000000, .freq = true },
[3] = { .suffix = "ghz", .multiplier = 1000000000, .freq = true },
[4] = { .suffix = "ms", .multiplier = 1000, .freq = false }, /* T = 1/f */
[5] = { .suffix = "us", .multiplier = 1, .freq = false },
[6] = { .suffix = "ns", .multiplier = 1, .freq = false },
[7] = { .suffix = NULL, .multiplier = 0, .freq = false },
};
unsigned long convert_string_to_microseconds(const char *buf) {
unsigned char ch = 0;
char numbers[10];
char letters[4];
const char *bufptr = buf;
int i = 0;
unsigned long microseconds = 0;
unsigned long numeric_part = 0;
int found_suffix = -1;
int numbers_index = 0, letters_index = 0;
while(bufptr && *bufptr && (ch = *bufptr) && isdigit(ch) && numbers_index < (sizeof(numbers)-1)) {
numbers[numbers_index++] = *bufptr++;
}
numbers[numbers_index] = 0;
while(bufptr && *bufptr && (ch = *bufptr) && strchr("usmhznhzkg",tolower(ch)) && letters_index < (sizeof(letters)-1)) {
letters[letters_index++] = tolower(*bufptr);
bufptr++;
}
letters[letters_index] = 0;
sscanf(numbers,"%lu",&numeric_part);
while(suffixes[i].suffix) {
if(!strcmp(suffixes[i].suffix,letters)) {
found_suffix = i;
break;
}
i++;
}
if(found_suffix > -1) {
if(suffixes[found_suffix].freq) {
microseconds = 1000000 / (numeric_part * suffixes[found_suffix].multiplier);
} else {
microseconds = suffixes[found_suffix].multiplier * numeric_part;
}
}
return microseconds;
}
static const unsigned int prescale_divisor[13] = {120,
180,
240,
360,
480,
480, /* Invalid Option */
480, /* Invalid Option */
480, /* Invalid Option */
12000,
24000,
36000,
48000,
72000};
/*
* Find the best prescale value for the period
* We want to get the highest period cycle count possible, so we look
* make a run through the prescale values looking for numbers over
* min_optimal_period_cycles. If none are found then root though again
* taking anything that works
*/
enum sun4i_pwm_prescale pwm_get_best_prescale(unsigned long long period_in) {
int i;
unsigned long period = period_in;
const unsigned long min_optimal_period_cycles = MAX_CYCLES / 2;
const unsigned long min_period_cycles = 0x02;
enum sun4i_pwm_prescale best_prescale = 0;
best_prescale = -1;
for(i = 0 ; i < 13 ; i++) {
unsigned long int check_value = (prescale_divisor[i] /24);
if(check_value < 1 || check_value > period) {
continue;
}
if(((period / check_value) >= min_optimal_period_cycles) &&
((period / check_value) <= MAX_CYCLES)) {
best_prescale = i;
break;
}
}
if(best_prescale > 13) {
for(i = 0 ; i < 13 ; i++) {
unsigned long int check_value = (prescale_divisor[i] /24);
if(check_value < 1 || check_value > period) {
continue;
}
if(((period / check_value) >= min_period_cycles) &&
((period / check_value) <= MAX_CYCLES)) {
best_prescale = i;
break;
}
}
}
if(best_prescale > sizeof(prescale_divisor)) {
best_prescale = -EINVAL; /* Something that's not zero - use invalid prescale value */
}
/* handle invalid options */
if(best_prescale > 4 && best_prescale < 8) {
best_prescale = 4;
}
return best_prescale;
}
/*
* return the number of cycles for the channel period computed from the microseconds
* for the period. Allwinner docs call this "entire" cycles
*/
unsigned int get_entire_cycles(struct sun4i_pwm_available_channel *chan) {
unsigned int entire_cycles = 0x01;
if (prescale_divisor[chan->prescale] * MAX_CYCLES > 0) {
entire_cycles = chan->period / (prescale_divisor[chan->prescale] /24);
}
if(entire_cycles > MAX_CYCLES) {entire_cycles = MAX_CYCLES;}
return entire_cycles;
}
/*
* return the number of cycles for the channel duty computed from the microseconds
* for the duty. Allwinner docs call this "active" cycles
*/
unsigned int get_active_cycles(struct sun4i_pwm_available_channel *chan) {
unsigned int active_cycles = 0x01;
unsigned int entire_cycles = get_entire_cycles(chan);
if ((prescale_divisor[chan->prescale] / 24) > 0) {
active_cycles = (chan->duty / (prescale_divisor[chan->prescale] / 24));
}
if(active_cycles > entire_cycles) {active_cycles = entire_cycles;}
if(active_cycles > MAX_CYCLES) {active_cycles = MAX_CYCLES;}
return active_cycles;
}
/*
* When the duty is set, compute the number of microseconds
* based on the period.
*/
void fixup_duty(struct sun4i_pwm_available_channel *chan) {
chan->ctrl_backup.initializer = chan->ctrl_current.initializer;
chan->ctrl_current.initializer = readl(chan->ctrl_addr);
if(chan->duty_percent > 0 && chan->duty_percent < 100) {
chan->duty = chan->period * chan->duty_percent / 100;
} else if(chan->duty_percent == 100) {
chan->duty = chan->period;
} else if(chan->duty_percent == 0 && chan->period) { /* bad things happen if both are 0. */
chan->duty = 0;
} else {
chan->duty = 1;
}
}
/*
* Stores the run (enable) bit.
*/
static ssize_t pwm_run_store(struct device *dev,struct device_attribute *attr, const char *buf, size_t size) {
struct sun4i_pwm_available_channel *chan = dev_get_drvdata(dev);
ssize_t status = -EINVAL;
int enable = 0;
sscanf(buf,"%d",&enable);
if(enable < 2) {
status = pwm_set_mode(enable, chan);
}
return size;
}
static ssize_t pwm_duty_percent_store(struct device *dev,struct device_attribute *attr, const char *buf, size_t size) {
unsigned int duty_percent = 0;
struct sun4i_pwm_available_channel *chan = dev_get_drvdata(dev);
sscanf(buf,"%u",&duty_percent);
if(duty_percent > 100) {
size = -EINVAL;
} else {
chan->duty_percent = duty_percent;
if(chan->period) {
fixup_duty(chan);
pwm_set_period_and_duty(chan);
// pwm_set_mode(NO_ENABLE_CHANGE,chan);
}
}
return size;
}
static ssize_t pwm_pulse_store(struct device *dev,struct device_attribute *attr, const char *buf, size_t size) {
struct sun4i_pwm_available_channel *chan = dev_get_drvdata(dev);
ssize_t status = -EINVAL;
int pulse = 0;
sscanf(buf,"%d",&pulse);
if(pulse < 2) {
switch (chan->channel) {
case 0:
chan->ctrl_backup.initializer = chan->ctrl_current.initializer;
chan->ctrl_current.initializer = readl(chan->ctrl_addr);
chan->ctrl_current.s.ch0_pulse_start = pulse;
writel(chan->ctrl_current.initializer,chan->ctrl_addr);
break;
case 1:
chan->ctrl_backup.initializer = chan->ctrl_current.initializer;
chan->ctrl_current.initializer = readl(chan->ctrl_addr);
chan->ctrl_current.s.ch1_pulse_start = pulse;
writel(chan->ctrl_current.initializer,chan->ctrl_addr);
break;
default:
status = -EINVAL;
break;
}
status = size;
}
return status;
}
int pwm_set_period_and_duty(struct sun4i_pwm_available_channel *chan) {
int return_val = -EINVAL;
union sun4i_pwm_ctrl_u pwm_ctrl, pwm_backup;
union sun4i_pwm_period_u current_period;
unsigned int entire_cycles = get_entire_cycles(chan);
unsigned int active_cycles = get_active_cycles(chan);
pwm_backup.initializer = pwm_ctrl.initializer = readl(chan->ctrl_addr);
current_period.initializer = readl(chan->period_reg_addr);
chan->period_reg.initializer = 0;
if(chan->period == chan->duty) {
entire_cycles = active_cycles > 0 ? active_cycles-1 : entire_cycles;
}
if(entire_cycles >= active_cycles && entire_cycles) {
chan->period_reg.s.pwm_entire_cycles = entire_cycles;
chan->period_reg.s.pwm_active_cycles = active_cycles;
} else {
/*
chan->period_reg.s.pwm_entire_cycles = MAX_CYCLES;
chan->period_reg.s.pwm_active_cycles = MAX_CYCLES-1;
*/
chan->period_reg.s.pwm_active_cycles = chan->period_reg.s.pwm_entire_cycles;
}
if(chan->period_reg.initializer == current_period.initializer) {
return return_val;
}
writel(chan->period_reg.initializer, chan->period_reg_addr);
return return_val;
}
ssize_t pwm_set_mode(unsigned int enable, struct sun4i_pwm_available_channel *chan) {
ssize_t status = 0;
if(enable == NO_ENABLE_CHANGE) {
switch (chan->channel) {
case 0:
enable = chan->ctrl_current.s.ch0_en;
break;
case 1:
enable = chan->ctrl_current.s.ch1_en;
break;
default:
status = -EINVAL;
break;
}
}
chan->ctrl_backup.initializer = chan->ctrl_current.initializer;
chan->ctrl_current.initializer = readl(chan->ctrl_addr);
if(enable == 1) {
switch (chan->channel) {
case 0:
/* chan->ctrl_current.s.ch0_prescaler = 0; */
chan->ctrl_current.s.ch0_mode = 0;
chan->ctrl_current.s.ch0_en = 0;
chan->ctrl_current.s.ch0_clk_gating = 0;
break;
case 1:
/* chan->ctrl_current.s.ch1_prescaler = 0; */
chan->ctrl_current.s.ch1_mode = 0;
chan->ctrl_current.s.ch1_en = 1;
chan->ctrl_current.s.ch1_clk_gating = 0;
break;
default:
status = -EINVAL;
break;
}
if(status) {
return status;
}
writel(chan->ctrl_current.initializer,chan->ctrl_addr);
chan->pin_current.initializer = readl(chan->pin_addr);
if(chan->pin_mask.s0.pin0_select) {
chan->pin_current.s0.pin0_select = SELECT_PWM;
}
if(chan->pin_mask.s0.pin1_select) {
chan->pin_current.s0.pin1_select = SELECT_PWM;
}
if(chan->pin_mask.s0.pin2_select) {
chan->pin_current.s0.pin2_select = SELECT_PWM;
}
if(chan->pin_mask.s0.pin3_select) {
chan->pin_current.s0.pin3_select = SELECT_PWM;
}
if(chan->pin_mask.s0.pin4_select) {
chan->pin_current.s0.pin4_select = SELECT_PWM;
}
if(chan->pin_mask.s0.pin5_select) {
chan->pin_current.s0.pin5_select = SELECT_PWM;
}
if(chan->pin_mask.s0.pin6_select) {
chan->pin_current.s0.pin6_select = SELECT_PWM;
}
if(chan->pin_mask.s0.pin7_select) {
chan->pin_current.s0.pin7_select = SELECT_PWM;
}
if(chan->channel == 0) {
chan->ctrl_current.s.ch0_prescaler = chan->prescale;
} else {
chan->ctrl_current.s.ch1_prescaler = chan->prescale;
}
pwm_set_period_and_duty(chan);
writel(chan->pin_current.initializer,chan->pin_addr);
writel(chan->ctrl_current.initializer,chan->ctrl_addr);
switch (chan->channel) {
case 0:
chan->ctrl_current.s.ch0_en = 1;
chan->ctrl_current.s.ch0_clk_gating = 1;
break;
case 1:
chan->ctrl_current.s.ch1_en = 1;
chan->ctrl_current.s.ch1_clk_gating = 1;
break;
}
writel(chan->ctrl_current.initializer,chan->ctrl_addr);
} else if (enable == 0) {
switch (chan->channel) {
case 0:
chan->ctrl_current.s.ch0_clk_gating = 0;
chan->ctrl_current.s.ch0_en = enable;
break;
case 1:
chan->ctrl_current.s.ch1_clk_gating = 0;
chan->ctrl_current.s.ch1_en = enable;
break;
default:
status = -EINVAL;
break;
}
if(!status) {
chan->pin_current.initializer &= ~chan->pin_mask.initializer;
chan->pin_current.initializer |= (chan->pin_backup.initializer & chan->pin_mask.initializer);
writel(chan->pin_current.initializer,chan->pin_addr);
writel(chan->ctrl_current.initializer,chan->ctrl_addr);
}
}
return status;
}
irqreturn_t pwm_handle_irq(int irq, void *dev_id)
{
return IRQ_HANDLED;
}
void pwm_dump_ioreg_cfg(struct sun4i_ioreg_cfg0 *cfg,
struct sun4i_ioreg_cfg0 *cfg_compare,
const char *name) {
const char * cfg_pin0_select_diff = "";
const char * cfg_pin1_select_diff = "";
const char * cfg_pin2_select_diff = "";
const char * cfg_pin3_select_diff = "";
const char * cfg_pin4_select_diff = "";
const char * cfg_pin5_select_diff = "";
const char * cfg_pin6_select_diff = "";
const char * cfg_pin7_select_diff = "";
if(!cfg || !name) {
return;
}
if(cfg && cfg_compare) {
cfg_pin0_select_diff = (const char *)(cfg->pin0_select != cfg_compare->pin0_select ? " ******" : "");
cfg_pin1_select_diff = (const char *)(cfg->pin1_select != cfg_compare->pin1_select ? " ******" : "");
cfg_pin2_select_diff = (const char *)(cfg->pin2_select != cfg_compare->pin2_select ? " ******" : "");
cfg_pin3_select_diff = (const char *)(cfg->pin3_select != cfg_compare->pin3_select ? " ******" : "");
cfg_pin4_select_diff = (const char *)(cfg->pin4_select != cfg_compare->pin4_select ? " ******" : "");
cfg_pin5_select_diff = (const char *)(cfg->pin5_select != cfg_compare->pin5_select ? " ******" : "");
cfg_pin6_select_diff = (const char *)(cfg->pin6_select != cfg_compare->pin6_select ? " ******" : "");
cfg_pin7_select_diff = (const char *)(cfg->pin7_select != cfg_compare->pin7_select ? " ******" : "");
}
printk(KERN_INFO "%s: pin0( 8)_select : 0x%x %s",name,cfg->pin0_select,cfg_pin0_select_diff);
printk(KERN_INFO "%s: pin1( 9)_select : 0x%x %s",name,cfg->pin1_select,cfg_pin1_select_diff);
printk(KERN_INFO "%s: pin2(10)_select : 0x%x %s",name,cfg->pin2_select,cfg_pin2_select_diff);
printk(KERN_INFO "%s: pin3(11)_select : 0x%x %s",name,cfg->pin3_select,cfg_pin3_select_diff);
printk(KERN_INFO "%s: pin4(12)_select : 0x%x %s",name,cfg->pin4_select,cfg_pin4_select_diff);
printk(KERN_INFO "%s: pin5(13)_select : 0x%x %s",name,cfg->pin5_select,cfg_pin5_select_diff);
printk(KERN_INFO "%s: pin6(14)_select : 0x%x %s",name,cfg->pin6_select,cfg_pin6_select_diff);
printk(KERN_INFO "%s: pin7(15)_select : 0x%x %s",name,cfg->pin7_select,cfg_pin7_select_diff);
printk(KERN_INFO "%s: pin_ctl: 0x%x",name,*(unsigned int *)cfg);
}
void pwm_dump_ioreg_pull(struct ioreg_pull *cfg,
struct ioreg_pull *cfg_compare,
const char *name) {
char *pin_state[4] = {
"Disable",
"Pull Up",
"Pull Down",
"Reserved"
};
const char * cfg_pin0_diff = "";
const char * cfg_pin1_diff = "";
const char * cfg_pin2_diff = "";
const char * cfg_pin3_diff = "";
const char * cfg_pin4_diff = "";
const char * cfg_pin5_diff = "";
const char * cfg_pin6_diff = "";
const char * cfg_pin7_diff = "";
const char * cfg_pin8_diff = "";
const char * cfg_pin9_diff = "";
const char * cfg_pin10_diff = "";
const char * cfg_pin11_diff = "";
const char * cfg_pin12_diff = "";
const char * cfg_pin13_diff = "";
const char * cfg_pin14_diff = "";
const char * cfg_pin15_diff = "";
if(!cfg || !name) {
return;
}
if(cfg && cfg_compare) {
cfg_pin0_diff = (const char *)(cfg->pin0 != cfg_compare->pin0 ? " ******" : "");
cfg_pin1_diff = (const char *)(cfg->pin1 != cfg_compare->pin1 ? " ******" : "");
cfg_pin2_diff = (const char *)(cfg->pin2 != cfg_compare->pin2 ? " ******" : "");
cfg_pin3_diff = (const char *)(cfg->pin3 != cfg_compare->pin3 ? " ******" : "");
cfg_pin4_diff = (const char *)(cfg->pin4 != cfg_compare->pin4 ? " ******" : "");
cfg_pin5_diff = (const char *)(cfg->pin5 != cfg_compare->pin5 ? " ******" : "");
cfg_pin6_diff = (const char *)(cfg->pin6 != cfg_compare->pin6 ? " ******" : "");
cfg_pin7_diff = (const char *)(cfg->pin7 != cfg_compare->pin7 ? " ******" : "");
cfg_pin8_diff = (const char *)(cfg->pin8 != cfg_compare->pin8 ? " ******" : "");
cfg_pin9_diff = (const char *)(cfg->pin9 != cfg_compare->pin9 ? " ******" : "");
cfg_pin10_diff = (const char *)(cfg->pin10 != cfg_compare->pin10 ? " ******" : "");
cfg_pin11_diff = (const char *)(cfg->pin11 != cfg_compare->pin11 ? " ******" : "");
cfg_pin12_diff = (const char *)(cfg->pin12 != cfg_compare->pin12 ? " ******" : "");
cfg_pin13_diff = (const char *)(cfg->pin13 != cfg_compare->pin13 ? " ******" : "");
cfg_pin14_diff = (const char *)(cfg->pin14 != cfg_compare->pin14 ? " ******" : "");
cfg_pin15_diff = (const char *)(cfg->pin15 != cfg_compare->pin15 ? " ******" : "");
}
printk(KERN_INFO "%s: pin0 : 0x%x (%s) %s",name,cfg->pin0,pin_state[cfg->pin0],cfg_pin0_diff);
printk(KERN_INFO "%s: pin1 : 0x%x (%s) %s",name,cfg->pin1,pin_state[cfg->pin1],cfg_pin1_diff);
printk(KERN_INFO "%s: pin2 : 0x%x (%s) %s",name,cfg->pin2,pin_state[cfg->pin2],cfg_pin2_diff);
printk(KERN_INFO "%s: pin3 : 0x%x (%s) %s",name,cfg->pin3,pin_state[cfg->pin3],cfg_pin3_diff);
printk(KERN_INFO "%s: pin4 : 0x%x (%s) %s",name,cfg->pin4,pin_state[cfg->pin4],cfg_pin4_diff);
printk(KERN_INFO "%s: pin5 : 0x%x (%s) %s",name,cfg->pin5,pin_state[cfg->pin5],cfg_pin5_diff);
printk(KERN_INFO "%s: pin6 : 0x%x (%s) %s",name,cfg->pin6,pin_state[cfg->pin6],cfg_pin6_diff);
printk(KERN_INFO "%s: pin7 : 0x%x (%s) %s",name,cfg->pin7,pin_state[cfg->pin7],cfg_pin7_diff);
printk(KERN_INFO "%s: pin8 : 0x%x (%s) %s",name,cfg->pin8,pin_state[cfg->pin8],cfg_pin8_diff);
printk(KERN_INFO "%s: pin9 : 0x%x (%s) %s",name,cfg->pin9,pin_state[cfg->pin9],cfg_pin9_diff);
printk(KERN_INFO "%s: pin10 : 0x%x (%s) %s",name,cfg->pin10,pin_state[cfg->pin10],cfg_pin10_diff);
printk(KERN_INFO "%s: pin11 : 0x%x (%s) %s",name,cfg->pin11,pin_state[cfg->pin11],cfg_pin11_diff);
printk(KERN_INFO "%s: pin12 : 0x%x (%s) %s",name,cfg->pin12,pin_state[cfg->pin12],cfg_pin12_diff);
printk(KERN_INFO "%s: pin13 : 0x%x (%s) %s",name,cfg->pin13,pin_state[cfg->pin13],cfg_pin13_diff);
printk(KERN_INFO "%s: pin14 : 0x%x (%s) %s",name,cfg->pin14,pin_state[cfg->pin14],cfg_pin14_diff);
printk(KERN_INFO "%s: pin15 : 0x%x (%s) %s",name,cfg->pin15,pin_state[cfg->pin15],cfg_pin15_diff);
}
void pwm_dump_pwm_period_reg(struct sun4i_pwm_period *period,
struct sun4i_pwm_period *period_compare,const char *name) {
char period_entire_cycles_diff[25] = {0};
char period_active_cycles_diff[25] = {0};
if(!period || !name) {
return;
}
if(period && period_compare) {
if(period->pwm_entire_cycles != period_compare->pwm_entire_cycles) {
sprintf(period_entire_cycles_diff," *** was **** 0x%x",period_compare->pwm_entire_cycles);
}
if(period->pwm_active_cycles != period_compare->pwm_active_cycles) {
sprintf(period_active_cycles_diff," *** was **** 0x%x",period_compare->pwm_active_cycles);
}
}
printk(KERN_INFO "%s: entire_cycles: 0x%x %s",name,period->pwm_entire_cycles,period_entire_cycles_diff);
printk(KERN_INFO "%s: active_cycles: 0x%x %s",name,period->pwm_active_cycles,period_active_cycles_diff);
printk(KERN_INFO "%s: period_reg: 0x%x",name,*(unsigned int *)period);
}
void pwm_dump_pwm_ctrl_reg(struct sun4i_pwm_ctrl *pwm,
struct sun4i_pwm_ctrl *pwm_compare,const char *name) {
const char * ch0_prescaler_diff = "";
const char * ch0_en_diff = "";
const char * ch0_act_state_diff = "";
const char * ch0_clk_gating_diff = "";
const char * ch0_mode_diff = "";
const char * ch0_pulse_start_diff = "";
const char * ch1_prescaler_diff = "";
const char * ch1_en_diff = "";
const char * ch1_act_state_diff = "";
const char * ch1_clk_gating_diff = "";
const char * ch1_mode_diff = "";
const char * ch1_pulse_start_diff = "";
if(!pwm || !name) {
return;
}
if(pwm && pwm_compare) {
ch0_prescaler_diff = (const char *)(pwm->ch0_prescaler != pwm_compare->ch0_prescaler ? " ******" : "");
ch0_en_diff = (const char *)(pwm->ch0_en != pwm_compare->ch0_en ? " ******" : "");
ch0_act_state_diff = (const char *)(pwm->ch0_act_state != pwm_compare->ch0_act_state ? " ******" : "");
ch0_clk_gating_diff = (const char *)(pwm->ch0_clk_gating != pwm_compare->ch0_clk_gating ? " ******" : "");
ch0_mode_diff = (const char *)(pwm->ch0_mode != pwm_compare->ch0_mode ? " ******" : "");
ch0_pulse_start_diff = (const char *)(pwm->ch0_pulse_start != pwm_compare->ch0_pulse_start ? " ******" : "");
ch1_prescaler_diff = (const char *)(pwm->ch1_prescaler != pwm_compare->ch1_prescaler ? " ******" : "");
ch1_en_diff = (const char *)(pwm->ch1_en != pwm_compare->ch1_en ? " ******" : "");
ch1_act_state_diff = (const char *)(pwm->ch1_act_state != pwm_compare->ch1_act_state ? " ******" : "");
ch1_clk_gating_diff = (const char *)(pwm->ch1_clk_gating != pwm_compare->ch1_clk_gating ? " ******" : "");
ch1_mode_diff = (const char *)(pwm->ch1_mode != pwm_compare->ch1_mode ? " ******" : "");
ch1_pulse_start_diff = (const char *)(pwm->ch1_pulse_start != pwm_compare->ch1_pulse_start ? " ******" : "");
}
printk(KERN_INFO "%s: ch0_prescaler: 0x%x %s",name,pwm->ch0_prescaler,ch0_prescaler_diff);
printk(KERN_INFO "%s: ch0_en: 0x%x %s",name,pwm->ch0_en,ch0_en_diff);
printk(KERN_INFO "%s: ch0_act_state: 0x%x %s",name,pwm->ch0_act_state,ch0_act_state_diff);
printk(KERN_INFO "%s: ch0_clk_gating: 0x%x %s",name,pwm->ch0_clk_gating,ch0_clk_gating_diff);
printk(KERN_INFO "%s: ch0_mode: 0x%x %s",name,pwm->ch0_mode,ch0_mode_diff);
printk(KERN_INFO "%s: ch0_pulse_start: 0x%x %s",name,pwm->ch0_pulse_start,ch0_pulse_start_diff);
printk(KERN_INFO "%s: ch1_prescaler: 0x%x %s",name,pwm->ch1_prescaler,ch1_prescaler_diff);
printk(KERN_INFO "%s: ch1_en: 0x%x %s",name,pwm->ch1_en,ch1_en_diff);
printk(KERN_INFO "%s: ch1_act_state: 0x%x %s",name,pwm->ch1_act_state,ch1_act_state_diff);
printk(KERN_INFO "%s: ch1_clk_gating: 0x%x %s",name,pwm->ch1_clk_gating,ch1_clk_gating_diff);
printk(KERN_INFO "%s: ch1_mode: 0x%x %s",name,pwm->ch1_mode,ch1_mode_diff);
printk(KERN_INFO "%s: ch1_pulse_start: 0x%x %s",name,pwm->ch1_pulse_start,ch1_pulse_start_diff);
printk(KERN_INFO "%s: ch1_ctrl_reg: 0x%x",name,*(unsigned int *)pwm);
printk(KERN_INFO "%s: sizeof(*pwm) = %d",name,sizeof(*pwm));
}
void pwm_setup_available_channels( void ) {
void * timer_base = ioremap(SW_PA_TIMERC_IO_BASE, 0x400); /* 0x01c20c00 */
void * PWM_CTRL_REG_BASE = timer_base + 0x200; /* 0x01c20e00 */
void * portc_io_base = ioremap(SW_PA_PORTC_IO_BASE,0x400); /* 0x01c20800 */
void * PB_CFG0_REG = (portc_io_base + 0x24); /* 0x01C20824 */
void * PI_CFG0_REG = (portc_io_base + 0x120); /* 0x01c20920 */
/* unsigned long pb_multi_driving_reg_val = 0; */
/*void * PB_PULL0_REG = (portc_io_base + 0x040);*/ /* 0x01c20840 */
/*void * PI_PULL0_REG = (portc_io_base + 0x13c);*/ /* 0x01c2091c */
/*void * PH_CFG0_REG = (portc_io_base + 0xfc);*/ /* 0x01c208fc */
/*void * PH_CFG1_REG = (portc_io_base + 0x100);*/ /* 0x01c20900 */
/*void * PH_PULL0_REG = (portc_io_base + 0x118);*/ /* 0x01c20918 */
/*void * PB_MULTI_DRIVING_REG = (portc_io_base + 0x38); */ /* 0x01C20838 */
pwm_available_chan[0].use_count = 0;
pwm_available_chan[0].ctrl_addr = PWM_CTRL_REG_BASE;
pwm_available_chan[0].pin_addr = PB_CFG0_REG;
pwm_available_chan[0].period_reg_addr = pwm_available_chan[0].ctrl_addr + 0x04;
pwm_available_chan[0].channel = 0;
pwm_available_chan[0].period_reg_backup.initializer = readl(pwm_available_chan[0].period_reg_addr);
pwm_available_chan[0].ctrl_backup.initializer = readl(pwm_available_chan[0].ctrl_addr);
pwm_available_chan[0].ctrl_mask.initializer = 0;
pwm_available_chan[0].ctrl_mask.s.ch0_prescaler = 0x0f;
pwm_available_chan[0].ctrl_mask.s.ch0_en = 0x01;
pwm_available_chan[0].ctrl_mask.s.ch0_act_state = 0x01;
pwm_available_chan[0].ctrl_mask.s.ch0_clk_gating = 0x00;
pwm_available_chan[0].ctrl_mask.s.ch0_mode = 0x01;
pwm_available_chan[0].ctrl_mask.s.ch0_pulse_start = 0x01;
pwm_available_chan[0].ctrl_current.initializer = 0;
pwm_available_chan[0].pin_backup.initializer = readl(pwm_available_chan[0].pin_addr);
pwm_available_chan[0].pin_mask.s0.pin2_select = 0x07;
pwm_available_chan[0].pin_current.s0.pin2_select = 0x02;
pwm_available_chan[0].pin_name = "PB2";
pwm_available_chan[0].period = 30000;
pwm_available_chan[0].duty_percent = 50;
pwm_period_store(pwm0,&dev_attr_period,"300hz\n",6);
pwm_duty_percent_store(pwm0,&dev_attr_duty_percent,"50\n",3);
pwm_polarity_store(pwm0,&dev_attr_polarity,"1\n",2);
pwm_pulse_store(pwm0,&dev_attr_pulse,"0\n",2);
pwm_run_store(pwm0,&dev_attr_run,"0\n",2);
pwm_available_chan[1].use_count = 0;
pwm_available_chan[1].ctrl_addr = PWM_CTRL_REG_BASE;
pwm_available_chan[1].pin_addr = PI_CFG0_REG;
pwm_available_chan[1].period_reg_addr = pwm_available_chan[1].ctrl_addr + 0x08;
pwm_available_chan[1].channel = 1;
pwm_available_chan[1].period_reg_backup.initializer = readl(pwm_available_chan[1].period_reg_addr);
pwm_available_chan[1].ctrl_backup.initializer = readl(pwm_available_chan[1].ctrl_addr);
pwm_available_chan[1].ctrl_mask.initializer = 0;
pwm_available_chan[1].ctrl_mask.s.ch1_prescaler = 0x0f;
pwm_available_chan[1].ctrl_mask.s.ch1_en = 0x01;
pwm_available_chan[1].ctrl_mask.s.ch1_act_state = 0x01;
pwm_available_chan[1].ctrl_mask.s.ch1_clk_gating = 0x00;
pwm_available_chan[1].ctrl_mask.s.ch1_mode = 0x01;
pwm_available_chan[1].ctrl_mask.s.ch1_pulse_start = 0x01;
pwm_available_chan[1].ctrl_current.initializer = 0;
pwm_available_chan[1].pin_backup.initializer = readl(pwm_available_chan[1].pin_addr);
pwm_available_chan[1].pin_mask.initializer = 0;
pwm_available_chan[1].pin_mask.s0.pin3_select = 0x07;
pwm_available_chan[1].pin_current.s0.pin3_select = 0x02;
pwm_available_chan[1].pin_name = "PI3";
pwm_available_chan[1].period = 30000;
pwm_available_chan[1].duty_percent = 50;
pwm_period_store(pwm1,&dev_attr_period,"300hz\n",6);
pwm_duty_percent_store(pwm1,&dev_attr_duty_percent,"50\n",3);
pwm_polarity_store(pwm1,&dev_attr_polarity,"1\n",2);
pwm_pulse_store(pwm1,&dev_attr_pulse,"0\n",2);
pwm_run_store(pwm1,&dev_attr_run,"0\n",2);
printk(KERN_INFO "pwm-sunxi: Initialized...");
/*
pb_multi_driving_reg_val = readl(PB_MULTI_DRIVING_REG);
printk(KERN_INFO "pb_multi_drive = %lx",pb_multi_driving_reg_val);
pb_multi_driving_reg_val |= (0x03 << 4);
writel(pb_multi_driving_reg_val,PB_MULTI_DRIVING_REG);
*/
}
struct pwm_device {
struct sun4i_pwm_available_channel *chan;
};
struct pwm_device pwm_devices[2] = {
[0] = {.chan = &pwm_available_chan[0]},
[1] = {.chan = &pwm_available_chan[1]}
};
struct pwm_device *pwm_request(int pwm_id, const char *label)
{
struct pwm_device *pwm;
int found = 0;