144 lines
3.3 KiB
C
144 lines
3.3 KiB
C
/*
|
|
* Copyright (C) ST-Ericsson SA 2010
|
|
*
|
|
* Author: Arun R Murthy <arun.murthy@stericsson.com>
|
|
* License terms: GNU General Public License (GPL) version 2
|
|
*/
|
|
#include <linux/err.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/pwm.h>
|
|
#include <linux/mfd/abx500.h>
|
|
#include <linux/mfd/abx500/ab8500.h>
|
|
#include <linux/module.h>
|
|
|
|
/*
|
|
* PWM Out generators
|
|
* Bank: 0x10
|
|
*/
|
|
#define AB8500_PWM_OUT_CTRL1_REG 0x60
|
|
#define AB8500_PWM_OUT_CTRL2_REG 0x61
|
|
#define AB8500_PWM_OUT_CTRL7_REG 0x66
|
|
|
|
struct ab8500_pwm_chip {
|
|
struct pwm_chip chip;
|
|
};
|
|
|
|
static int ab8500_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
|
|
int duty_ns, int period_ns)
|
|
{
|
|
int ret = 0;
|
|
unsigned int higher_val, lower_val;
|
|
u8 reg;
|
|
|
|
/*
|
|
* get the first 8 bits that are be written to
|
|
* AB8500_PWM_OUT_CTRL1_REG[0:7]
|
|
*/
|
|
lower_val = duty_ns & 0x00FF;
|
|
/*
|
|
* get bits [9:10] that are to be written to
|
|
* AB8500_PWM_OUT_CTRL2_REG[0:1]
|
|
*/
|
|
higher_val = ((duty_ns & 0x0300) >> 8);
|
|
|
|
reg = AB8500_PWM_OUT_CTRL1_REG + ((chip->base - 1) * 2);
|
|
|
|
ret = abx500_set_register_interruptible(chip->dev, AB8500_MISC,
|
|
reg, (u8)lower_val);
|
|
if (ret < 0)
|
|
return ret;
|
|
ret = abx500_set_register_interruptible(chip->dev, AB8500_MISC,
|
|
(reg + 1), (u8)higher_val);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int ab8500_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
|
|
{
|
|
int ret;
|
|
|
|
ret = abx500_mask_and_set_register_interruptible(chip->dev,
|
|
AB8500_MISC, AB8500_PWM_OUT_CTRL7_REG,
|
|
1 << (chip->base - 1), 1 << (chip->base - 1));
|
|
if (ret < 0)
|
|
dev_err(chip->dev, "%s: Failed to enable PWM, Error %d\n",
|
|
pwm->label, ret);
|
|
return ret;
|
|
}
|
|
|
|
static void ab8500_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
|
|
{
|
|
int ret;
|
|
|
|
ret = abx500_mask_and_set_register_interruptible(chip->dev,
|
|
AB8500_MISC, AB8500_PWM_OUT_CTRL7_REG,
|
|
1 << (chip->base - 1), 0);
|
|
if (ret < 0)
|
|
dev_err(chip->dev, "%s: Failed to disable PWM, Error %d\n",
|
|
pwm->label, ret);
|
|
}
|
|
|
|
static const struct pwm_ops ab8500_pwm_ops = {
|
|
.config = ab8500_pwm_config,
|
|
.enable = ab8500_pwm_enable,
|
|
.disable = ab8500_pwm_disable,
|
|
.owner = THIS_MODULE,
|
|
};
|
|
|
|
static int ab8500_pwm_probe(struct platform_device *pdev)
|
|
{
|
|
struct ab8500_pwm_chip *ab8500;
|
|
int err;
|
|
|
|
/*
|
|
* Nothing to be done in probe, this is required to get the
|
|
* device which is required for ab8500 read and write
|
|
*/
|
|
ab8500 = devm_kzalloc(&pdev->dev, sizeof(*ab8500), GFP_KERNEL);
|
|
if (ab8500 == NULL)
|
|
return -ENOMEM;
|
|
|
|
ab8500->chip.dev = &pdev->dev;
|
|
ab8500->chip.ops = &ab8500_pwm_ops;
|
|
ab8500->chip.base = pdev->id;
|
|
ab8500->chip.npwm = 1;
|
|
|
|
err = pwmchip_add(&ab8500->chip);
|
|
if (err < 0)
|
|
return err;
|
|
|
|
dev_dbg(&pdev->dev, "pwm probe successful\n");
|
|
platform_set_drvdata(pdev, ab8500);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int ab8500_pwm_remove(struct platform_device *pdev)
|
|
{
|
|
struct ab8500_pwm_chip *ab8500 = platform_get_drvdata(pdev);
|
|
int err;
|
|
|
|
err = pwmchip_remove(&ab8500->chip);
|
|
if (err < 0)
|
|
return err;
|
|
|
|
dev_dbg(&pdev->dev, "pwm driver removed\n");
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct platform_driver ab8500_pwm_driver = {
|
|
.driver = {
|
|
.name = "ab8500-pwm",
|
|
},
|
|
.probe = ab8500_pwm_probe,
|
|
.remove = ab8500_pwm_remove,
|
|
};
|
|
module_platform_driver(ab8500_pwm_driver);
|
|
|
|
MODULE_AUTHOR("Arun MURTHY <arun.murthy@stericsson.com>");
|
|
MODULE_DESCRIPTION("AB8500 Pulse Width Modulation Driver");
|
|
MODULE_ALIAS("platform:ab8500-pwm");
|
|
MODULE_LICENSE("GPL v2");
|