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linux/drivers/pwm/pwm-lp3943.c

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pwm: Add LP3943 PWM driver This is the other of the LP3943 MFD driver. LP3943 can be used as a PWM generator, up to 2 channels. * Two PWM generators supported * Supported PWM operations request, free, config, enable and disable * Pin assignment A driver data, 'pin_used' is checked when a PWM is requested. If the output pin is already assigned, then returns as failure. If the pin is available, 'pin_used' is set. When the PWM is not used anymore, then it is cleared. It is defined as unsigned long type for atomic bit operation APIs, but only LSB 16bits are used because LP3943 has 16 outputs. Signed-off-by: Milo Kim <milo.kim@ti.com> Acked-by: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Lee Jones <lee.jones@linaro.org>
2013-12-06 10:18:43 +08:00
/*
* TI/National Semiconductor LP3943 PWM driver
*
* Copyright 2013 Texas Instruments
*
* Author: Milo Kim <milo.kim@ti.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; version 2.
*/
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/mfd/lp3943.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/pwm.h>
#include <linux/slab.h>
#define LP3943_MAX_DUTY 255
#define LP3943_MIN_PERIOD 6250
#define LP3943_MAX_PERIOD 1600000
struct lp3943_pwm {
struct pwm_chip chip;
struct lp3943 *lp3943;
struct lp3943_platform_data *pdata;
};
static inline struct lp3943_pwm *to_lp3943_pwm(struct pwm_chip *_chip)
{
return container_of(_chip, struct lp3943_pwm, chip);
}
static struct lp3943_pwm_map *
lp3943_pwm_request_map(struct lp3943_pwm *lp3943_pwm, int hwpwm)
{
struct lp3943_platform_data *pdata = lp3943_pwm->pdata;
struct lp3943 *lp3943 = lp3943_pwm->lp3943;
struct lp3943_pwm_map *pwm_map;
int i, offset;
pwm_map = kzalloc(sizeof(*pwm_map), GFP_KERNEL);
if (!pwm_map)
return ERR_PTR(-ENOMEM);
pwm_map->output = pdata->pwms[hwpwm]->output;
pwm_map->num_outputs = pdata->pwms[hwpwm]->num_outputs;
for (i = 0; i < pwm_map->num_outputs; i++) {
offset = pwm_map->output[i];
/* Return an error if the pin is already assigned */
pwm: lp3943: Fix potential memory leak during request Fix a memory leak in the lp3943_pwm_request_map() error handling path. Make sure already allocated pwm map memory is freed correctly. Detected by Coverity: CID 1162829. Signed-off-by: Christian Engelmayer <cengelma@gmx.at> Acked-by: Milo Kim <milo.kim@ti.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-01-24 05:32:20 +08:00
if (test_and_set_bit(offset, &lp3943->pin_used)) {
kfree(pwm_map);
pwm: Add LP3943 PWM driver This is the other of the LP3943 MFD driver. LP3943 can be used as a PWM generator, up to 2 channels. * Two PWM generators supported * Supported PWM operations request, free, config, enable and disable * Pin assignment A driver data, 'pin_used' is checked when a PWM is requested. If the output pin is already assigned, then returns as failure. If the pin is available, 'pin_used' is set. When the PWM is not used anymore, then it is cleared. It is defined as unsigned long type for atomic bit operation APIs, but only LSB 16bits are used because LP3943 has 16 outputs. Signed-off-by: Milo Kim <milo.kim@ti.com> Acked-by: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Lee Jones <lee.jones@linaro.org>
2013-12-06 10:18:43 +08:00
return ERR_PTR(-EBUSY);
pwm: lp3943: Fix potential memory leak during request Fix a memory leak in the lp3943_pwm_request_map() error handling path. Make sure already allocated pwm map memory is freed correctly. Detected by Coverity: CID 1162829. Signed-off-by: Christian Engelmayer <cengelma@gmx.at> Acked-by: Milo Kim <milo.kim@ti.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-01-24 05:32:20 +08:00
}
pwm: Add LP3943 PWM driver This is the other of the LP3943 MFD driver. LP3943 can be used as a PWM generator, up to 2 channels. * Two PWM generators supported * Supported PWM operations request, free, config, enable and disable * Pin assignment A driver data, 'pin_used' is checked when a PWM is requested. If the output pin is already assigned, then returns as failure. If the pin is available, 'pin_used' is set. When the PWM is not used anymore, then it is cleared. It is defined as unsigned long type for atomic bit operation APIs, but only LSB 16bits are used because LP3943 has 16 outputs. Signed-off-by: Milo Kim <milo.kim@ti.com> Acked-by: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Lee Jones <lee.jones@linaro.org>
2013-12-06 10:18:43 +08:00
}
return pwm_map;
}
static int lp3943_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
{
struct lp3943_pwm *lp3943_pwm = to_lp3943_pwm(chip);
struct lp3943_pwm_map *pwm_map;
pwm_map = lp3943_pwm_request_map(lp3943_pwm, pwm->hwpwm);
if (IS_ERR(pwm_map))
return PTR_ERR(pwm_map);
return pwm_set_chip_data(pwm, pwm_map);
}
static void lp3943_pwm_free_map(struct lp3943_pwm *lp3943_pwm,
struct lp3943_pwm_map *pwm_map)
{
struct lp3943 *lp3943 = lp3943_pwm->lp3943;
int i, offset;
for (i = 0; i < pwm_map->num_outputs; i++) {
offset = pwm_map->output[i];
clear_bit(offset, &lp3943->pin_used);
}
kfree(pwm_map);
}
static void lp3943_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
{
struct lp3943_pwm *lp3943_pwm = to_lp3943_pwm(chip);
struct lp3943_pwm_map *pwm_map = pwm_get_chip_data(pwm);
lp3943_pwm_free_map(lp3943_pwm, pwm_map);
}
static int lp3943_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
int duty_ns, int period_ns)
{
struct lp3943_pwm *lp3943_pwm = to_lp3943_pwm(chip);
struct lp3943 *lp3943 = lp3943_pwm->lp3943;
u8 val, reg_duty, reg_prescale;
int err;
/*
* How to configure the LP3943 PWMs
*
* 1) Period = 6250 ~ 1600000
* 2) Prescale = period / 6250 -1
* 3) Duty = input duty
*
* Prescale and duty are register values
*/
if (pwm->hwpwm == 0) {
reg_prescale = LP3943_REG_PRESCALE0;
reg_duty = LP3943_REG_PWM0;
} else {
reg_prescale = LP3943_REG_PRESCALE1;
reg_duty = LP3943_REG_PWM1;
}
period_ns = clamp(period_ns, LP3943_MIN_PERIOD, LP3943_MAX_PERIOD);
val = (u8)(period_ns / LP3943_MIN_PERIOD - 1);
err = lp3943_write_byte(lp3943, reg_prescale, val);
if (err)
return err;
val = (u8)(duty_ns * LP3943_MAX_DUTY / period_ns);
return lp3943_write_byte(lp3943, reg_duty, val);
}
static int lp3943_pwm_set_mode(struct lp3943_pwm *lp3943_pwm,
struct lp3943_pwm_map *pwm_map,
u8 val)
{
struct lp3943 *lp3943 = lp3943_pwm->lp3943;
const struct lp3943_reg_cfg *mux = lp3943->mux_cfg;
int i, index, err;
for (i = 0; i < pwm_map->num_outputs; i++) {
index = pwm_map->output[i];
err = lp3943_update_bits(lp3943, mux[index].reg,
mux[index].mask,
val << mux[index].shift);
if (err)
return err;
}
return 0;
}
static int lp3943_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
{
struct lp3943_pwm *lp3943_pwm = to_lp3943_pwm(chip);
struct lp3943_pwm_map *pwm_map = pwm_get_chip_data(pwm);
u8 val;
if (pwm->hwpwm == 0)
val = LP3943_DIM_PWM0;
else
val = LP3943_DIM_PWM1;
/*
* Each PWM generator is set to control any of outputs of LP3943.
* To enable/disable the PWM, these output pins should be configured.
*/
return lp3943_pwm_set_mode(lp3943_pwm, pwm_map, val);
}
static void lp3943_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
{
struct lp3943_pwm *lp3943_pwm = to_lp3943_pwm(chip);
struct lp3943_pwm_map *pwm_map = pwm_get_chip_data(pwm);
/*
* LP3943 outputs are open-drain, so the pin should be configured
* when the PWM is disabled.
*/
lp3943_pwm_set_mode(lp3943_pwm, pwm_map, LP3943_GPIO_OUT_HIGH);
}
static const struct pwm_ops lp3943_pwm_ops = {
.request = lp3943_pwm_request,
.free = lp3943_pwm_free,
.config = lp3943_pwm_config,
.enable = lp3943_pwm_enable,
.disable = lp3943_pwm_disable,
.owner = THIS_MODULE,
};
static int lp3943_pwm_parse_dt(struct device *dev,
struct lp3943_pwm *lp3943_pwm)
{
static const char * const name[] = { "ti,pwm0", "ti,pwm1", };
struct device_node *node = dev->of_node;
struct lp3943_platform_data *pdata;
struct lp3943_pwm_map *pwm_map;
enum lp3943_pwm_output *output;
int i, err, proplen, count = 0;
u32 num_outputs;
if (!node)
return -EINVAL;
pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
if (!pdata)
return -ENOMEM;
/*
* Read the output map configuration from the device tree.
* Each of the two PWM generators can drive zero or more outputs.
*/
for (i = 0; i < LP3943_NUM_PWMS; i++) {
if (!of_get_property(node, name[i], &proplen))
continue;
num_outputs = proplen / sizeof(u32);
if (num_outputs == 0)
continue;
treewide: devm_kzalloc() -> devm_kcalloc() The devm_kzalloc() function has a 2-factor argument form, devm_kcalloc(). This patch replaces cases of: devm_kzalloc(handle, a * b, gfp) with: devm_kcalloc(handle, a * b, gfp) as well as handling cases of: devm_kzalloc(handle, a * b * c, gfp) with: devm_kzalloc(handle, array3_size(a, b, c), gfp) as it's slightly less ugly than: devm_kcalloc(handle, array_size(a, b), c, gfp) This does, however, attempt to ignore constant size factors like: devm_kzalloc(handle, 4 * 1024, gfp) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. Some manual whitespace fixes were needed in this patch, as Coccinelle really liked to write "=devm_kcalloc..." instead of "= devm_kcalloc...". The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ expression HANDLE; type TYPE; expression THING, E; @@ ( devm_kzalloc(HANDLE, - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | devm_kzalloc(HANDLE, - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression HANDLE; expression COUNT; typedef u8; typedef __u8; @@ ( devm_kzalloc(HANDLE, - sizeof(u8) * (COUNT) + COUNT , ...) | devm_kzalloc(HANDLE, - sizeof(__u8) * (COUNT) + COUNT , ...) | devm_kzalloc(HANDLE, - sizeof(char) * (COUNT) + COUNT , ...) | devm_kzalloc(HANDLE, - sizeof(unsigned char) * (COUNT) + COUNT , ...) | devm_kzalloc(HANDLE, - sizeof(u8) * COUNT + COUNT , ...) | devm_kzalloc(HANDLE, - sizeof(__u8) * COUNT + COUNT , ...) | devm_kzalloc(HANDLE, - sizeof(char) * COUNT + COUNT , ...) | devm_kzalloc(HANDLE, - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ expression HANDLE; type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - devm_kzalloc + devm_kcalloc (HANDLE, - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - devm_kzalloc + devm_kcalloc (HANDLE, - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - devm_kzalloc + devm_kcalloc (HANDLE, - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - devm_kzalloc + devm_kcalloc (HANDLE, - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - devm_kzalloc + devm_kcalloc (HANDLE, - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - devm_kzalloc + devm_kcalloc (HANDLE, - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - devm_kzalloc + devm_kcalloc (HANDLE, - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - devm_kzalloc + devm_kcalloc (HANDLE, - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ expression HANDLE; identifier SIZE, COUNT; @@ - devm_kzalloc + devm_kcalloc (HANDLE, - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression HANDLE; expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( devm_kzalloc(HANDLE, - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | devm_kzalloc(HANDLE, - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | devm_kzalloc(HANDLE, - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | devm_kzalloc(HANDLE, - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | devm_kzalloc(HANDLE, - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | devm_kzalloc(HANDLE, - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | devm_kzalloc(HANDLE, - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | devm_kzalloc(HANDLE, - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression HANDLE; expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( devm_kzalloc(HANDLE, - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | devm_kzalloc(HANDLE, - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | devm_kzalloc(HANDLE, - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | devm_kzalloc(HANDLE, - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | devm_kzalloc(HANDLE, - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | devm_kzalloc(HANDLE, - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ expression HANDLE; identifier STRIDE, SIZE, COUNT; @@ ( devm_kzalloc(HANDLE, - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | devm_kzalloc(HANDLE, - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | devm_kzalloc(HANDLE, - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | devm_kzalloc(HANDLE, - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | devm_kzalloc(HANDLE, - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | devm_kzalloc(HANDLE, - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | devm_kzalloc(HANDLE, - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | devm_kzalloc(HANDLE, - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression HANDLE; expression E1, E2, E3; constant C1, C2, C3; @@ ( devm_kzalloc(HANDLE, C1 * C2 * C3, ...) | devm_kzalloc(HANDLE, - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | devm_kzalloc(HANDLE, - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | devm_kzalloc(HANDLE, - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | devm_kzalloc(HANDLE, - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression HANDLE; expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( devm_kzalloc(HANDLE, sizeof(THING) * C2, ...) | devm_kzalloc(HANDLE, sizeof(TYPE) * C2, ...) | devm_kzalloc(HANDLE, C1 * C2 * C3, ...) | devm_kzalloc(HANDLE, C1 * C2, ...) | - devm_kzalloc + devm_kcalloc (HANDLE, - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - devm_kzalloc + devm_kcalloc (HANDLE, - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - devm_kzalloc + devm_kcalloc (HANDLE, - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - devm_kzalloc + devm_kcalloc (HANDLE, - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - devm_kzalloc + devm_kcalloc (HANDLE, - (E1) * E2 + E1, E2 , ...) | - devm_kzalloc + devm_kcalloc (HANDLE, - (E1) * (E2) + E1, E2 , ...) | - devm_kzalloc + devm_kcalloc (HANDLE, - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-13 05:07:58 +08:00
output = devm_kcalloc(dev, num_outputs, sizeof(*output),
pwm: Add LP3943 PWM driver This is the other of the LP3943 MFD driver. LP3943 can be used as a PWM generator, up to 2 channels. * Two PWM generators supported * Supported PWM operations request, free, config, enable and disable * Pin assignment A driver data, 'pin_used' is checked when a PWM is requested. If the output pin is already assigned, then returns as failure. If the pin is available, 'pin_used' is set. When the PWM is not used anymore, then it is cleared. It is defined as unsigned long type for atomic bit operation APIs, but only LSB 16bits are used because LP3943 has 16 outputs. Signed-off-by: Milo Kim <milo.kim@ti.com> Acked-by: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Lee Jones <lee.jones@linaro.org>
2013-12-06 10:18:43 +08:00
GFP_KERNEL);
if (!output)
return -ENOMEM;
err = of_property_read_u32_array(node, name[i], output,
num_outputs);
if (err)
return err;
pwm_map = devm_kzalloc(dev, sizeof(*pwm_map), GFP_KERNEL);
if (!pwm_map)
return -ENOMEM;
pwm_map->output = output;
pwm_map->num_outputs = num_outputs;
pdata->pwms[i] = pwm_map;
count++;
}
if (count == 0)
return -ENODATA;
lp3943_pwm->pdata = pdata;
return 0;
}
static int lp3943_pwm_probe(struct platform_device *pdev)
{
struct lp3943 *lp3943 = dev_get_drvdata(pdev->dev.parent);
struct lp3943_pwm *lp3943_pwm;
int ret;
lp3943_pwm = devm_kzalloc(&pdev->dev, sizeof(*lp3943_pwm), GFP_KERNEL);
if (!lp3943_pwm)
return -ENOMEM;
lp3943_pwm->pdata = lp3943->pdata;
if (!lp3943_pwm->pdata) {
if (IS_ENABLED(CONFIG_OF))
ret = lp3943_pwm_parse_dt(&pdev->dev, lp3943_pwm);
else
ret = -ENODEV;
if (ret)
return ret;
}
lp3943_pwm->lp3943 = lp3943;
lp3943_pwm->chip.dev = &pdev->dev;
lp3943_pwm->chip.ops = &lp3943_pwm_ops;
lp3943_pwm->chip.npwm = LP3943_NUM_PWMS;
platform_set_drvdata(pdev, lp3943_pwm);
return pwmchip_add(&lp3943_pwm->chip);
}
static int lp3943_pwm_remove(struct platform_device *pdev)
{
struct lp3943_pwm *lp3943_pwm = platform_get_drvdata(pdev);
return pwmchip_remove(&lp3943_pwm->chip);
}
#ifdef CONFIG_OF
static const struct of_device_id lp3943_pwm_of_match[] = {
{ .compatible = "ti,lp3943-pwm", },
{ }
};
MODULE_DEVICE_TABLE(of, lp3943_pwm_of_match);
#endif
static struct platform_driver lp3943_pwm_driver = {
.probe = lp3943_pwm_probe,
.remove = lp3943_pwm_remove,
.driver = {
.name = "lp3943-pwm",
.of_match_table = of_match_ptr(lp3943_pwm_of_match),
},
};
module_platform_driver(lp3943_pwm_driver);
MODULE_DESCRIPTION("LP3943 PWM driver");
MODULE_ALIAS("platform:lp3943-pwm");
MODULE_AUTHOR("Milo Kim");
MODULE_LICENSE("GPL");
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