64a67d4762
The DT binding doc says reset-gpios is an optional property but the code
currently bails out if it is omitted.
This is a regression since it breaks previously working device trees.
Fix it by restoring the original documented behaviour.
Fixes: ce03727586 ("mmc: pwrseq_simple: use GPIO descriptors array API")
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Martin Fuzzey <mfuzzey@parkeon.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
136 lines
3.2 KiB
C
136 lines
3.2 KiB
C
/*
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* Copyright (C) 2014 Linaro Ltd
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*
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* Author: Ulf Hansson <ulf.hansson@linaro.org>
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*
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* License terms: GNU General Public License (GPL) version 2
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*
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* Simple MMC power sequence management
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*/
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#include <linux/clk.h>
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#include <linux/kernel.h>
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#include <linux/slab.h>
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#include <linux/device.h>
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#include <linux/err.h>
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#include <linux/of_gpio.h>
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#include <linux/gpio/consumer.h>
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#include <linux/mmc/host.h>
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#include "pwrseq.h"
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struct mmc_pwrseq_simple {
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struct mmc_pwrseq pwrseq;
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bool clk_enabled;
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struct clk *ext_clk;
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struct gpio_descs *reset_gpios;
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};
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static void mmc_pwrseq_simple_set_gpios_value(struct mmc_pwrseq_simple *pwrseq,
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int value)
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{
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struct gpio_descs *reset_gpios = pwrseq->reset_gpios;
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if (!IS_ERR(reset_gpios)) {
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int i;
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int values[reset_gpios->ndescs];
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for (i = 0; i < reset_gpios->ndescs; i++)
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values[i] = value;
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gpiod_set_array_value_cansleep(
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reset_gpios->ndescs, reset_gpios->desc, values);
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}
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}
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static void mmc_pwrseq_simple_pre_power_on(struct mmc_host *host)
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{
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struct mmc_pwrseq_simple *pwrseq = container_of(host->pwrseq,
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struct mmc_pwrseq_simple, pwrseq);
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if (!IS_ERR(pwrseq->ext_clk) && !pwrseq->clk_enabled) {
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clk_prepare_enable(pwrseq->ext_clk);
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pwrseq->clk_enabled = true;
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}
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mmc_pwrseq_simple_set_gpios_value(pwrseq, 1);
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}
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static void mmc_pwrseq_simple_post_power_on(struct mmc_host *host)
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{
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struct mmc_pwrseq_simple *pwrseq = container_of(host->pwrseq,
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struct mmc_pwrseq_simple, pwrseq);
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mmc_pwrseq_simple_set_gpios_value(pwrseq, 0);
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}
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static void mmc_pwrseq_simple_power_off(struct mmc_host *host)
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{
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struct mmc_pwrseq_simple *pwrseq = container_of(host->pwrseq,
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struct mmc_pwrseq_simple, pwrseq);
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mmc_pwrseq_simple_set_gpios_value(pwrseq, 1);
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if (!IS_ERR(pwrseq->ext_clk) && pwrseq->clk_enabled) {
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clk_disable_unprepare(pwrseq->ext_clk);
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pwrseq->clk_enabled = false;
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}
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}
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static void mmc_pwrseq_simple_free(struct mmc_host *host)
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{
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struct mmc_pwrseq_simple *pwrseq = container_of(host->pwrseq,
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struct mmc_pwrseq_simple, pwrseq);
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if (!IS_ERR(pwrseq->reset_gpios))
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gpiod_put_array(pwrseq->reset_gpios);
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if (!IS_ERR(pwrseq->ext_clk))
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clk_put(pwrseq->ext_clk);
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kfree(pwrseq);
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}
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static const struct mmc_pwrseq_ops mmc_pwrseq_simple_ops = {
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.pre_power_on = mmc_pwrseq_simple_pre_power_on,
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.post_power_on = mmc_pwrseq_simple_post_power_on,
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.power_off = mmc_pwrseq_simple_power_off,
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.free = mmc_pwrseq_simple_free,
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};
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struct mmc_pwrseq *mmc_pwrseq_simple_alloc(struct mmc_host *host,
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struct device *dev)
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{
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struct mmc_pwrseq_simple *pwrseq;
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int ret = 0;
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pwrseq = kzalloc(sizeof(*pwrseq), GFP_KERNEL);
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if (!pwrseq)
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return ERR_PTR(-ENOMEM);
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pwrseq->ext_clk = clk_get(dev, "ext_clock");
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if (IS_ERR(pwrseq->ext_clk) &&
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PTR_ERR(pwrseq->ext_clk) != -ENOENT) {
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ret = PTR_ERR(pwrseq->ext_clk);
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goto free;
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}
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pwrseq->reset_gpios = gpiod_get_array(dev, "reset", GPIOD_OUT_HIGH);
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if (IS_ERR(pwrseq->reset_gpios) &&
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PTR_ERR(pwrseq->reset_gpios) != -ENOENT &&
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PTR_ERR(pwrseq->reset_gpios) != -ENOSYS) {
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ret = PTR_ERR(pwrseq->reset_gpios);
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goto clk_put;
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}
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pwrseq->pwrseq.ops = &mmc_pwrseq_simple_ops;
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return &pwrseq->pwrseq;
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clk_put:
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if (!IS_ERR(pwrseq->ext_clk))
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clk_put(pwrseq->ext_clk);
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free:
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kfree(pwrseq);
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return ERR_PTR(ret);
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}
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