Many MMC host drivers already use OF data to obtain their platform-specific configuration. Each of them is doing this in its special way, whereas many parameters are identical and can easily be generalised. This patch adds such a generic parser. So far it only adds and handles very few basic properties. New ones can be added in the future as required.
Signed-off-by: Guennadi Liakhovetski <[email protected]> Cc: Grant Likely <[email protected]> --- drivers/mmc/core/Makefile | 2 + drivers/mmc/core/of.c | 91 +++++++++++++++++++++++++++++++++++++++++++++ include/linux/mmc/host.h | 12 ++++++ 3 files changed, 105 insertions(+), 0 deletions(-) create mode 100644 drivers/mmc/core/of.c diff --git a/drivers/mmc/core/Makefile b/drivers/mmc/core/Makefile index 38ed210..aa7727e 100644 --- a/drivers/mmc/core/Makefile +++ b/drivers/mmc/core/Makefile @@ -9,4 +9,6 @@ mmc_core-y := core.o bus.o host.o \ sdio_cis.o sdio_io.o sdio_irq.o \ quirks.o slot-gpio.o +mmc_core-$(CONFIG_OF) += of.o + mmc_core-$(CONFIG_DEBUG_FS) += debugfs.o diff --git a/drivers/mmc/core/of.c b/drivers/mmc/core/of.c new file mode 100644 index 0000000..2fba115 --- /dev/null +++ b/drivers/mmc/core/of.c @@ -0,0 +1,91 @@ +/* + * Generic MMC OF parser + * + * Copyright (C) 2012, Guennadi Liakhovetski <[email protected]> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/device.h> +#include <linux/err.h> +#include <linux/mmc/host.h> +#include <linux/mmc/slot-gpio.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_gpio.h> + +/* + * Implementation-specific capabilities, that the controller driver usually + * cannot autodetect and has to receive from an external source, e.g., from + * platform data or from OF are: + * + * MMC_CAP_4_BIT_DATA: depends on the board layout: how many data lines are + * connected + * MMC_CAP_8_BIT_DATA: ditto + * MMC_CAP2_INVERTED_CD: card-detect active-low (0 == card present) + * MMC_CAP2_INVERTED_RO: write-protect active-low (0 == read-only) + * Some features might be supplied as GPIO bindings: + * MMC_CAP_SDIO_IRQ: depends, whether an SDIO IRQ line is connected + * MMC_CAP_NEEDS_POLL: is a card-detect pin connected? + * MMC_CAP_NONREMOVABLE: can also be a board feature, also, some media-types + * (eMMC?) are intrinsicly non-removable + * Others can be retrieved from regulators: + * MMC_CAP_POWER_OFF_CARD + */ + +void mmc_of_get(struct mmc_host *mmc) +{ + struct device *dev = mmc_dev(mmc); + struct device_node *node = dev->of_node; + enum of_gpio_flags flags; + unsigned int gpio; + int ret; + + if (!node || !of_device_is_available(node)) + return; + + if (of_get_property(node, "mmc,4_bit_data", NULL)) + mmc->caps |= MMC_CAP_4_BIT_DATA; + if (of_get_property(node, "mmc,8_bit_data", NULL)) + mmc->caps |= MMC_CAP_8_BIT_DATA; + if (of_get_property(node, "mmc,sdio_irq", NULL)) + mmc->caps |= MMC_CAP_SDIO_IRQ; + if (of_get_property(node, "mmc,nonremovable", NULL)) + mmc->caps |= MMC_CAP_NONREMOVABLE; + if (of_get_property(node, "mmc,needs_poll", NULL)) + mmc->caps |= MMC_CAP_NEEDS_POLL; + if (of_get_property(node, "mmc,inverted_cd", NULL)) + mmc->caps2 |= MMC_CAP2_INVERTED_CD; + if (of_get_property(node, "mmc,inverted_ro", NULL)) + mmc->caps2 |= MMC_CAP2_INVERTED_RO; + + /* + * Both mmc_gpio_request_cd() and mmc_gpio_request_ro() check for + * gpio_valid(), so, no need to check for error + */ + + gpio = of_get_named_gpio_flags(node, "cd-gpios", 0, &flags); + ret = mmc_gpio_request_cd(mmc, gpio); + if (ret < 0) + dev_warn(mmc->parent, "Failed to obtain CD GPIO: %d\n", ret); + + gpio = of_get_named_gpio_flags(node, "ro-gpios", 0, &flags); + ret = mmc_gpio_request_ro(mmc, gpio); + if (ret < 0) + dev_warn(mmc->parent, "Failed to obtain RO GPIO: %d\n", ret); +} +EXPORT_SYMBOL(mmc_of_get); + +void mmc_of_put(struct mmc_host *mmc) +{ + struct device_node *node = mmc_dev(mmc)->of_node; + + if (!node || !of_device_is_available(node)) + return; + + mmc_gpio_free_ro(mmc); + mmc_gpio_free_cd(mmc); +} +EXPORT_SYMBOL(mmc_of_put); diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h index f8157a9..94b3805 100644 --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -450,4 +450,16 @@ static inline unsigned int mmc_host_clk_rate(struct mmc_host *host) return host->ios.clock; } #endif + +#ifdef CONFIG_OF +void mmc_of_get(struct mmc_host *mmc); +void mmc_of_put(struct mmc_host *mmc); +#else +static inline void mmc_of_get(struct mmc_host *mmc) +{ +} +static inline void mmc_of_put(struct mmc_host *mmc) +{ +} +#endif #endif /* LINUX_MMC_HOST_H */ -- 1.7.2.5 -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
