From 3aa8793f751d4cfcaca886e75ab30dfb00cf1d88 Mon Sep 17 00:00:00 2001 From: Ulf Hansson Date: Fri, 28 Nov 2014 14:38:36 +0100 Subject: [PATCH] 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 Tested-by: Javier Martinez Canillas Reviewed-by: Javier Martinez Canillas --- drivers/mmc/core/Makefile | 2 +- drivers/mmc/core/core.c | 7 ++++++ drivers/mmc/core/host.c | 4 +++- drivers/mmc/core/pwrseq.c | 50 +++++++++++++++++++++++++++++++++++++++ drivers/mmc/core/pwrseq.h | 40 +++++++++++++++++++++++++++++++ include/linux/mmc/host.h | 2 ++ 6 files changed, 103 insertions(+), 2 deletions(-) create mode 100644 drivers/mmc/core/pwrseq.c create mode 100644 drivers/mmc/core/pwrseq.h diff --git a/drivers/mmc/core/Makefile b/drivers/mmc/core/Makefile index 38ed210ce2f3..ccdd35f78256 100644 --- a/drivers/mmc/core/Makefile +++ b/drivers/mmc/core/Makefile @@ -8,5 +8,5 @@ mmc_core-y := core.o bus.o host.o \ sdio.o sdio_ops.o sdio_bus.o \ sdio_cis.o sdio_io.o sdio_irq.o \ quirks.o slot-gpio.o - +mmc_core-$(CONFIG_OF) += pwrseq.o mmc_core-$(CONFIG_DEBUG_FS) += debugfs.o diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c index d5c176e87951..1be7055548cb 100644 --- a/drivers/mmc/core/core.c +++ b/drivers/mmc/core/core.c @@ -40,6 +40,7 @@ #include "bus.h" #include "host.h" #include "sdio_bus.h" +#include "pwrseq.h" #include "mmc_ops.h" #include "sd_ops.h" @@ -1615,6 +1616,8 @@ void mmc_power_up(struct mmc_host *host, u32 ocr) mmc_host_clk_hold(host); + mmc_pwrseq_pre_power_on(host); + host->ios.vdd = fls(ocr) - 1; host->ios.power_mode = MMC_POWER_UP; /* Set initial state and call mmc_set_ios */ @@ -1645,6 +1648,8 @@ void mmc_power_up(struct mmc_host *host, u32 ocr) */ mmc_delay(10); + mmc_pwrseq_post_power_on(host); + mmc_host_clk_release(host); } @@ -1655,6 +1660,8 @@ void mmc_power_off(struct mmc_host *host) mmc_host_clk_hold(host); + mmc_pwrseq_power_off(host); + host->ios.clock = 0; host->ios.vdd = 0; diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c index 07636449b4de..8be0df758e68 100644 --- a/drivers/mmc/core/host.c +++ b/drivers/mmc/core/host.c @@ -30,6 +30,7 @@ #include "core.h" #include "host.h" #include "slot-gpio.h" +#include "pwrseq.h" #define cls_dev_to_mmc_host(d) container_of(d, struct mmc_host, class_dev) @@ -448,7 +449,7 @@ int mmc_of_parse(struct mmc_host *host) host->dsr_req = 0; } - return 0; + return mmc_pwrseq_alloc(host); } EXPORT_SYMBOL(mmc_of_parse); @@ -588,6 +589,7 @@ EXPORT_SYMBOL(mmc_remove_host); */ void mmc_free_host(struct mmc_host *host) { + mmc_pwrseq_free(host); put_device(&host->class_dev); } diff --git a/drivers/mmc/core/pwrseq.c b/drivers/mmc/core/pwrseq.c new file mode 100644 index 000000000000..bd087723929f --- /dev/null +++ b/drivers/mmc/core/pwrseq.c @@ -0,0 +1,50 @@ +/* + * Copyright (C) 2014 Linaro Ltd + * + * Author: Ulf Hansson + * + * License terms: GNU General Public License (GPL) version 2 + * + * MMC power sequence management + */ +#include + +#include "pwrseq.h" + + +int mmc_pwrseq_alloc(struct mmc_host *host) +{ + return 0; +} + +void mmc_pwrseq_pre_power_on(struct mmc_host *host) +{ + struct mmc_pwrseq *pwrseq = host->pwrseq; + + if (pwrseq && pwrseq->ops && pwrseq->ops->pre_power_on) + pwrseq->ops->pre_power_on(host); +} + +void mmc_pwrseq_post_power_on(struct mmc_host *host) +{ + struct mmc_pwrseq *pwrseq = host->pwrseq; + + if (pwrseq && pwrseq->ops && pwrseq->ops->post_power_on) + pwrseq->ops->post_power_on(host); +} + +void mmc_pwrseq_power_off(struct mmc_host *host) +{ + struct mmc_pwrseq *pwrseq = host->pwrseq; + + if (pwrseq && pwrseq->ops && pwrseq->ops->power_off) + pwrseq->ops->power_off(host); +} + +void mmc_pwrseq_free(struct mmc_host *host) +{ + struct mmc_pwrseq *pwrseq = host->pwrseq; + + if (pwrseq && pwrseq->ops && pwrseq->ops->free) + pwrseq->ops->free(host); +} diff --git a/drivers/mmc/core/pwrseq.h b/drivers/mmc/core/pwrseq.h new file mode 100644 index 000000000000..12aaf2b4745b --- /dev/null +++ b/drivers/mmc/core/pwrseq.h @@ -0,0 +1,40 @@ +/* + * Copyright (C) 2014 Linaro Ltd + * + * Author: Ulf Hansson + * + * 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); + +#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 diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h index b6bf718c3498..0c8cbe5d1550 100644 --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -195,6 +195,7 @@ struct mmc_context_info { }; struct regulator; +struct mmc_pwrseq; struct mmc_supply { struct regulator *vmmc; /* Card power supply */ @@ -206,6 +207,7 @@ struct mmc_host { struct device class_dev; int index; const struct mmc_host_ops *ops; + struct mmc_pwrseq *pwrseq; unsigned int f_min; unsigned int f_max; unsigned int f_init; -- 2.39.5