mirror of
https://github.com/torvalds/linux.git
synced 2024-12-11 05:33:09 +00:00
62c03ca3ff
Signed-off-by: Peter Chen <peter.chen@freescale.com> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
135 lines
3.2 KiB
C
135 lines
3.2 KiB
C
/*
|
|
* Copyright (C) 2014 Linaro Ltd
|
|
*
|
|
* Author: Ulf Hansson <ulf.hansson@linaro.org>
|
|
*
|
|
* License terms: GNU General Public License (GPL) version 2
|
|
*
|
|
* Simple MMC power sequence management
|
|
*/
|
|
#include <linux/clk.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/device.h>
|
|
#include <linux/err.h>
|
|
#include <linux/gpio/consumer.h>
|
|
|
|
#include <linux/mmc/host.h>
|
|
|
|
#include "pwrseq.h"
|
|
|
|
struct mmc_pwrseq_simple {
|
|
struct mmc_pwrseq pwrseq;
|
|
bool clk_enabled;
|
|
struct clk *ext_clk;
|
|
struct gpio_descs *reset_gpios;
|
|
};
|
|
|
|
static void mmc_pwrseq_simple_set_gpios_value(struct mmc_pwrseq_simple *pwrseq,
|
|
int value)
|
|
{
|
|
struct gpio_descs *reset_gpios = pwrseq->reset_gpios;
|
|
|
|
if (!IS_ERR(reset_gpios)) {
|
|
int i;
|
|
int values[reset_gpios->ndescs];
|
|
|
|
for (i = 0; i < reset_gpios->ndescs; i++)
|
|
values[i] = value;
|
|
|
|
gpiod_set_array_value_cansleep(
|
|
reset_gpios->ndescs, reset_gpios->desc, values);
|
|
}
|
|
}
|
|
|
|
static void mmc_pwrseq_simple_pre_power_on(struct mmc_host *host)
|
|
{
|
|
struct mmc_pwrseq_simple *pwrseq = container_of(host->pwrseq,
|
|
struct mmc_pwrseq_simple, pwrseq);
|
|
|
|
if (!IS_ERR(pwrseq->ext_clk) && !pwrseq->clk_enabled) {
|
|
clk_prepare_enable(pwrseq->ext_clk);
|
|
pwrseq->clk_enabled = true;
|
|
}
|
|
|
|
mmc_pwrseq_simple_set_gpios_value(pwrseq, 1);
|
|
}
|
|
|
|
static void mmc_pwrseq_simple_post_power_on(struct mmc_host *host)
|
|
{
|
|
struct mmc_pwrseq_simple *pwrseq = container_of(host->pwrseq,
|
|
struct mmc_pwrseq_simple, pwrseq);
|
|
|
|
mmc_pwrseq_simple_set_gpios_value(pwrseq, 0);
|
|
}
|
|
|
|
static void mmc_pwrseq_simple_power_off(struct mmc_host *host)
|
|
{
|
|
struct mmc_pwrseq_simple *pwrseq = container_of(host->pwrseq,
|
|
struct mmc_pwrseq_simple, pwrseq);
|
|
|
|
mmc_pwrseq_simple_set_gpios_value(pwrseq, 1);
|
|
|
|
if (!IS_ERR(pwrseq->ext_clk) && pwrseq->clk_enabled) {
|
|
clk_disable_unprepare(pwrseq->ext_clk);
|
|
pwrseq->clk_enabled = false;
|
|
}
|
|
}
|
|
|
|
static void mmc_pwrseq_simple_free(struct mmc_host *host)
|
|
{
|
|
struct mmc_pwrseq_simple *pwrseq = container_of(host->pwrseq,
|
|
struct mmc_pwrseq_simple, pwrseq);
|
|
|
|
if (!IS_ERR(pwrseq->reset_gpios))
|
|
gpiod_put_array(pwrseq->reset_gpios);
|
|
|
|
if (!IS_ERR(pwrseq->ext_clk))
|
|
clk_put(pwrseq->ext_clk);
|
|
|
|
kfree(pwrseq);
|
|
}
|
|
|
|
static const struct mmc_pwrseq_ops mmc_pwrseq_simple_ops = {
|
|
.pre_power_on = mmc_pwrseq_simple_pre_power_on,
|
|
.post_power_on = mmc_pwrseq_simple_post_power_on,
|
|
.power_off = mmc_pwrseq_simple_power_off,
|
|
.free = mmc_pwrseq_simple_free,
|
|
};
|
|
|
|
struct mmc_pwrseq *mmc_pwrseq_simple_alloc(struct mmc_host *host,
|
|
struct device *dev)
|
|
{
|
|
struct mmc_pwrseq_simple *pwrseq;
|
|
int ret = 0;
|
|
|
|
pwrseq = kzalloc(sizeof(*pwrseq), GFP_KERNEL);
|
|
if (!pwrseq)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
pwrseq->ext_clk = clk_get(dev, "ext_clock");
|
|
if (IS_ERR(pwrseq->ext_clk) &&
|
|
PTR_ERR(pwrseq->ext_clk) != -ENOENT) {
|
|
ret = PTR_ERR(pwrseq->ext_clk);
|
|
goto free;
|
|
}
|
|
|
|
pwrseq->reset_gpios = gpiod_get_array(dev, "reset", GPIOD_OUT_HIGH);
|
|
if (IS_ERR(pwrseq->reset_gpios) &&
|
|
PTR_ERR(pwrseq->reset_gpios) != -ENOENT &&
|
|
PTR_ERR(pwrseq->reset_gpios) != -ENOSYS) {
|
|
ret = PTR_ERR(pwrseq->reset_gpios);
|
|
goto clk_put;
|
|
}
|
|
|
|
pwrseq->pwrseq.ops = &mmc_pwrseq_simple_ops;
|
|
|
|
return &pwrseq->pwrseq;
|
|
clk_put:
|
|
if (!IS_ERR(pwrseq->ext_clk))
|
|
clk_put(pwrseq->ext_clk);
|
|
free:
|
|
kfree(pwrseq);
|
|
return ERR_PTR(ret);
|
|
}
|