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linux/drivers/mmc/core/pwrseq.h

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mmc: core: Initial support for MMC power sequences System on chip designs may specify a specific MMC power sequence. To successfully detect an (e)MMC/SD/SDIO card, that power sequence must be followed while initializing the card. To be able to handle these SOC specific power sequences, let's add a MMC power sequence interface. It provides the following functions to help the mmc core to deal with these power sequences. mmc_pwrseq_alloc() - Invoked from mmc_of_parse(), to initialize data. mmc_pwrseq_pre_power_on()- Invoked in the beginning of mmc_power_up(). mmc_pwrseq_post_power_on()- Invoked at the end in mmc_power_up(). mmc_pwrseq_power_off()- Invoked from mmc_power_off(). mmc_pwrseq_free() - Invoked from mmc_free_host(), to free data. Each MMC power sequence provider will be responsible to implement a set of callbacks. These callbacks mirrors the functions above. This patch adds the skeleton, following patches will extend the core of the MMC power sequence and add support for a specific simple MMC power sequence. Do note, since the mmc_pwrseq_alloc() is invoked from mmc_of_parse(), host drivers needs to make use of this API to enable the support for MMC power sequences. Moreover the MMC power sequence support depends on CONFIG_OF. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Tested-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk> Reviewed-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
2014-11-28 21:38:36 +08:00
/*
* Copyright (C) 2014 Linaro Ltd
*
* Author: Ulf Hansson <ulf.hansson@linaro.org>
*
* License terms: GNU General Public License (GPL) version 2
*/
#ifndef _MMC_CORE_PWRSEQ_H
#define _MMC_CORE_PWRSEQ_H
struct mmc_pwrseq_ops {
void (*pre_power_on)(struct mmc_host *host);
void (*post_power_on)(struct mmc_host *host);
void (*power_off)(struct mmc_host *host);
void (*free)(struct mmc_host *host);
};
struct mmc_pwrseq {
struct mmc_pwrseq_ops *ops;
};
#ifdef CONFIG_OF
int mmc_pwrseq_alloc(struct mmc_host *host);
void mmc_pwrseq_pre_power_on(struct mmc_host *host);
void mmc_pwrseq_post_power_on(struct mmc_host *host);
void mmc_pwrseq_power_off(struct mmc_host *host);
void mmc_pwrseq_free(struct mmc_host *host);
mmc: pwrseq: Initial support for the simple MMC power sequence provider To add the core part for the MMC power sequence, let's start by adding initial support for the simple MMC power sequence provider. In this initial step, the MMC power sequence node are fetched and the compatible string for the simple MMC power sequence provider are verified. At this point we don't parse the node for any properties, but instead that will be handled from following patches. Since there are no properties supported yet, let's just implement the ->alloc() and the ->free() callbacks. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Tested-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk> Reviewed-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
2014-12-05 21:36:58 +08:00
int mmc_pwrseq_simple_alloc(struct mmc_host *host, struct device *dev);
mmc: pwrseq: add driver for emmc hardware reset This patch provides a simple mmc-pwrseq-emmc driver, which controls single gpio line. It perform standard eMMC hw reset procedure, as descibed by Jedec 4.4 specification. This procedure is performed just after MMC core enabled power to the given mmc host (to fix possible issues if bootloader has left eMMC card in initialized or unknown state), and before performing complete system reboot (also in case of emergency reboot call). The latter is needed on boards, which doesn't have hardware reset logic connected to emmc card and (limited or broken) ROM bootloaders are unable to read second stage from the emmc card if the card is left in unknown or already initialized state. Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-02-03 21:07:53 +08:00
int mmc_pwrseq_emmc_alloc(struct mmc_host *host, struct device *dev);
mmc: pwrseq: Initial support for the simple MMC power sequence provider To add the core part for the MMC power sequence, let's start by adding initial support for the simple MMC power sequence provider. In this initial step, the MMC power sequence node are fetched and the compatible string for the simple MMC power sequence provider are verified. At this point we don't parse the node for any properties, but instead that will be handled from following patches. Since there are no properties supported yet, let's just implement the ->alloc() and the ->free() callbacks. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Tested-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk> Reviewed-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
2014-12-05 21:36:58 +08:00
mmc: core: Initial support for MMC power sequences System on chip designs may specify a specific MMC power sequence. To successfully detect an (e)MMC/SD/SDIO card, that power sequence must be followed while initializing the card. To be able to handle these SOC specific power sequences, let's add a MMC power sequence interface. It provides the following functions to help the mmc core to deal with these power sequences. mmc_pwrseq_alloc() - Invoked from mmc_of_parse(), to initialize data. mmc_pwrseq_pre_power_on()- Invoked in the beginning of mmc_power_up(). mmc_pwrseq_post_power_on()- Invoked at the end in mmc_power_up(). mmc_pwrseq_power_off()- Invoked from mmc_power_off(). mmc_pwrseq_free() - Invoked from mmc_free_host(), to free data. Each MMC power sequence provider will be responsible to implement a set of callbacks. These callbacks mirrors the functions above. This patch adds the skeleton, following patches will extend the core of the MMC power sequence and add support for a specific simple MMC power sequence. Do note, since the mmc_pwrseq_alloc() is invoked from mmc_of_parse(), host drivers needs to make use of this API to enable the support for MMC power sequences. Moreover the MMC power sequence support depends on CONFIG_OF. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Tested-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk> Reviewed-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
2014-11-28 21:38:36 +08:00
#else
static inline int mmc_pwrseq_alloc(struct mmc_host *host) { return 0; }
static inline void mmc_pwrseq_pre_power_on(struct mmc_host *host) {}
static inline void mmc_pwrseq_post_power_on(struct mmc_host *host) {}
static inline void mmc_pwrseq_power_off(struct mmc_host *host) {}
static inline void mmc_pwrseq_free(struct mmc_host *host) {}
#endif
#endif