diff options
Diffstat (limited to 'drivers/mmc/core/host.c')
| -rw-r--r-- | drivers/mmc/core/host.c | 496 |
1 files changed, 496 insertions, 0 deletions
diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c new file mode 100644 index 000000000..9de8a3553 --- /dev/null +++ b/drivers/mmc/core/host.c @@ -0,0 +1,496 @@ +/* + * linux/drivers/mmc/core/host.c + * + * Copyright (C) 2003 Russell King, All Rights Reserved. + * Copyright (C) 2007-2008 Pierre Ossman + * Copyright (C) 2010 Linus Walleij + * + * 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. + * + * MMC host class device management + */ + +#include <linux/device.h> +#include <linux/err.h> +#include <linux/idr.h> +#include <linux/of.h> +#include <linux/of_gpio.h> +#include <linux/pagemap.h> +#include <linux/export.h> +#include <linux/leds.h> +#include <linux/slab.h> + +#include <linux/mmc/host.h> +#include <linux/mmc/card.h> +#include <linux/mmc/slot-gpio.h> + +#include "core.h" +#include "host.h" +#include "slot-gpio.h" +#include "pwrseq.h" +#include "sdio_ops.h" + +#define cls_dev_to_mmc_host(d) container_of(d, struct mmc_host, class_dev) + +static DEFINE_IDA(mmc_host_ida); + +static void mmc_host_classdev_release(struct device *dev) +{ + struct mmc_host *host = cls_dev_to_mmc_host(dev); + ida_simple_remove(&mmc_host_ida, host->index); + kfree(host); +} + +static struct class mmc_host_class = { + .name = "mmc_host", + .dev_release = mmc_host_classdev_release, +}; + +int mmc_register_host_class(void) +{ + return class_register(&mmc_host_class); +} + +void mmc_unregister_host_class(void) +{ + class_unregister(&mmc_host_class); +} + +void mmc_retune_enable(struct mmc_host *host) +{ + host->can_retune = 1; + if (host->retune_period) + mod_timer(&host->retune_timer, + jiffies + host->retune_period * HZ); +} + +/* + * Pause re-tuning for a small set of operations. The pause begins after the + * next command and after first doing re-tuning. + */ +void mmc_retune_pause(struct mmc_host *host) +{ + if (!host->retune_paused) { + host->retune_paused = 1; + mmc_retune_needed(host); + mmc_retune_hold(host); + } +} +EXPORT_SYMBOL(mmc_retune_pause); + +void mmc_retune_unpause(struct mmc_host *host) +{ + if (host->retune_paused) { + host->retune_paused = 0; + mmc_retune_release(host); + } +} +EXPORT_SYMBOL(mmc_retune_unpause); + +void mmc_retune_disable(struct mmc_host *host) +{ + mmc_retune_unpause(host); + host->can_retune = 0; + del_timer_sync(&host->retune_timer); + host->retune_now = 0; + host->need_retune = 0; +} + +void mmc_retune_timer_stop(struct mmc_host *host) +{ + del_timer_sync(&host->retune_timer); +} +EXPORT_SYMBOL(mmc_retune_timer_stop); + +void mmc_retune_hold(struct mmc_host *host) +{ + if (!host->hold_retune) + host->retune_now = 1; + host->hold_retune += 1; +} + +void mmc_retune_release(struct mmc_host *host) +{ + if (host->hold_retune) + host->hold_retune -= 1; + else + WARN_ON(1); +} +EXPORT_SYMBOL(mmc_retune_release); + +int mmc_retune(struct mmc_host *host) +{ + bool return_to_hs400 = false; + int err; + + if (host->retune_now) + host->retune_now = 0; + else + return 0; + + if (!host->need_retune || host->doing_retune || !host->card) + return 0; + + host->need_retune = 0; + + host->doing_retune = 1; + + if (host->ios.timing == MMC_TIMING_MMC_HS400) { + err = mmc_hs400_to_hs200(host->card); + if (err) + goto out; + + return_to_hs400 = true; + } + + err = mmc_execute_tuning(host->card); + if (err) + goto out; + + if (return_to_hs400) + err = mmc_hs200_to_hs400(host->card); +out: + host->doing_retune = 0; + + return err; +} + +static void mmc_retune_timer(struct timer_list *t) +{ + struct mmc_host *host = from_timer(host, t, retune_timer); + + mmc_retune_needed(host); +} + +/** + * mmc_of_parse() - parse host's device-tree node + * @host: host whose node should be parsed. + * + * To keep the rest of the MMC subsystem unaware of whether DT has been + * used to to instantiate and configure this host instance or not, we + * parse the properties and set respective generic mmc-host flags and + * parameters. + */ +int mmc_of_parse(struct mmc_host *host) +{ + struct device *dev = host->parent; + u32 bus_width, drv_type, cd_debounce_delay_ms; + int ret; + bool cd_cap_invert, cd_gpio_invert = false; + bool ro_cap_invert, ro_gpio_invert = false; + + if (!dev || !dev_fwnode(dev)) + return 0; + + /* "bus-width" is translated to MMC_CAP_*_BIT_DATA flags */ + if (device_property_read_u32(dev, "bus-width", &bus_width) < 0) { + dev_dbg(host->parent, + "\"bus-width\" property is missing, assuming 1 bit.\n"); + bus_width = 1; + } + + switch (bus_width) { + case 8: + host->caps |= MMC_CAP_8_BIT_DATA; + /* Hosts capable of 8-bit transfers can also do 4 bits */ + case 4: + host->caps |= MMC_CAP_4_BIT_DATA; + break; + case 1: + break; + default: + dev_err(host->parent, + "Invalid \"bus-width\" value %u!\n", bus_width); + return -EINVAL; + } + + /* f_max is obtained from the optional "max-frequency" property */ + device_property_read_u32(dev, "max-frequency", &host->f_max); + + /* + * Configure CD and WP pins. They are both by default active low to + * match the SDHCI spec. If GPIOs are provided for CD and / or WP, the + * mmc-gpio helpers are used to attach, configure and use them. If + * polarity inversion is specified in DT, one of MMC_CAP2_CD_ACTIVE_HIGH + * and MMC_CAP2_RO_ACTIVE_HIGH capability-2 flags is set. If the + * "broken-cd" property is provided, the MMC_CAP_NEEDS_POLL capability + * is set. If the "non-removable" property is found, the + * MMC_CAP_NONREMOVABLE capability is set and no card-detection + * configuration is performed. + */ + + /* Parse Card Detection */ + if (device_property_read_bool(dev, "non-removable")) { + host->caps |= MMC_CAP_NONREMOVABLE; + } else { + cd_cap_invert = device_property_read_bool(dev, "cd-inverted"); + + if (device_property_read_u32(dev, "cd-debounce-delay-ms", + &cd_debounce_delay_ms)) + cd_debounce_delay_ms = 200; + + if (device_property_read_bool(dev, "broken-cd")) + host->caps |= MMC_CAP_NEEDS_POLL; + + ret = mmc_gpiod_request_cd(host, "cd", 0, true, + cd_debounce_delay_ms * 1000, + &cd_gpio_invert); + if (!ret) + dev_info(host->parent, "Got CD GPIO\n"); + else if (ret != -ENOENT && ret != -ENOSYS) + return ret; + + /* + * There are two ways to flag that the CD line is inverted: + * through the cd-inverted flag and by the GPIO line itself + * being inverted from the GPIO subsystem. This is a leftover + * from the times when the GPIO subsystem did not make it + * possible to flag a line as inverted. + * + * If the capability on the host AND the GPIO line are + * both inverted, the end result is that the CD line is + * not inverted. + */ + if (cd_cap_invert ^ cd_gpio_invert) + host->caps2 |= MMC_CAP2_CD_ACTIVE_HIGH; + } + + /* Parse Write Protection */ + ro_cap_invert = device_property_read_bool(dev, "wp-inverted"); + + ret = mmc_gpiod_request_ro(host, "wp", 0, false, 0, &ro_gpio_invert); + if (!ret) + dev_info(host->parent, "Got WP GPIO\n"); + else if (ret != -ENOENT && ret != -ENOSYS) + return ret; + + if (device_property_read_bool(dev, "disable-wp")) + host->caps2 |= MMC_CAP2_NO_WRITE_PROTECT; + + /* See the comment on CD inversion above */ + if (ro_cap_invert ^ ro_gpio_invert) + host->caps2 |= MMC_CAP2_RO_ACTIVE_HIGH; + + if (device_property_read_bool(dev, "cap-sd-highspeed")) + host->caps |= MMC_CAP_SD_HIGHSPEED; + if (device_property_read_bool(dev, "cap-mmc-highspeed")) + host->caps |= MMC_CAP_MMC_HIGHSPEED; + if (device_property_read_bool(dev, "sd-uhs-sdr12")) + host->caps |= MMC_CAP_UHS_SDR12; + if (device_property_read_bool(dev, "sd-uhs-sdr25")) + host->caps |= MMC_CAP_UHS_SDR25; + if (device_property_read_bool(dev, "sd-uhs-sdr50")) + host->caps |= MMC_CAP_UHS_SDR50; + if (device_property_read_bool(dev, "sd-uhs-sdr104")) + host->caps |= MMC_CAP_UHS_SDR104; + if (device_property_read_bool(dev, "sd-uhs-ddr50")) + host->caps |= MMC_CAP_UHS_DDR50; + if (device_property_read_bool(dev, "cap-power-off-card")) + host->caps |= MMC_CAP_POWER_OFF_CARD; + if (device_property_read_bool(dev, "cap-mmc-hw-reset")) + host->caps |= MMC_CAP_HW_RESET; + if (device_property_read_bool(dev, "cap-sdio-irq")) + host->caps |= MMC_CAP_SDIO_IRQ; + if (device_property_read_bool(dev, "full-pwr-cycle")) + host->caps2 |= MMC_CAP2_FULL_PWR_CYCLE; + if (device_property_read_bool(dev, "keep-power-in-suspend")) + host->pm_caps |= MMC_PM_KEEP_POWER; + if (device_property_read_bool(dev, "wakeup-source") || + device_property_read_bool(dev, "enable-sdio-wakeup")) /* legacy */ + host->pm_caps |= MMC_PM_WAKE_SDIO_IRQ; + if (device_property_read_bool(dev, "mmc-ddr-3_3v")) + host->caps |= MMC_CAP_3_3V_DDR; + if (device_property_read_bool(dev, "mmc-ddr-1_8v")) + host->caps |= MMC_CAP_1_8V_DDR; + if (device_property_read_bool(dev, "mmc-ddr-1_2v")) + host->caps |= MMC_CAP_1_2V_DDR; + if (device_property_read_bool(dev, "mmc-hs200-1_8v")) + host->caps2 |= MMC_CAP2_HS200_1_8V_SDR; + if (device_property_read_bool(dev, "mmc-hs200-1_2v")) + host->caps2 |= MMC_CAP2_HS200_1_2V_SDR; + if (device_property_read_bool(dev, "mmc-hs400-1_8v")) + host->caps2 |= MMC_CAP2_HS400_1_8V | MMC_CAP2_HS200_1_8V_SDR; + if (device_property_read_bool(dev, "mmc-hs400-1_2v")) + host->caps2 |= MMC_CAP2_HS400_1_2V | MMC_CAP2_HS200_1_2V_SDR; + if (device_property_read_bool(dev, "mmc-hs400-enhanced-strobe")) + host->caps2 |= MMC_CAP2_HS400_ES; + if (device_property_read_bool(dev, "no-sdio")) + host->caps2 |= MMC_CAP2_NO_SDIO; + if (device_property_read_bool(dev, "no-sd")) + host->caps2 |= MMC_CAP2_NO_SD; + if (device_property_read_bool(dev, "no-mmc")) + host->caps2 |= MMC_CAP2_NO_MMC; + + /* Must be after "non-removable" check */ + if (device_property_read_u32(dev, "fixed-emmc-driver-type", &drv_type) == 0) { + if (host->caps & MMC_CAP_NONREMOVABLE) + host->fixed_drv_type = drv_type; + else + dev_err(host->parent, + "can't use fixed driver type, media is removable\n"); + } + + host->dsr_req = !device_property_read_u32(dev, "dsr", &host->dsr); + if (host->dsr_req && (host->dsr & ~0xffff)) { + dev_err(host->parent, + "device tree specified broken value for DSR: 0x%x, ignoring\n", + host->dsr); + host->dsr_req = 0; + } + + device_property_read_u32(dev, "post-power-on-delay-ms", + &host->ios.power_delay_ms); + + return mmc_pwrseq_alloc(host); +} + +EXPORT_SYMBOL(mmc_of_parse); + +/** + * mmc_alloc_host - initialise the per-host structure. + * @extra: sizeof private data structure + * @dev: pointer to host device model structure + * + * Initialise the per-host structure. + */ +struct mmc_host *mmc_alloc_host(int extra, struct device *dev) +{ + int err; + struct mmc_host *host; + + host = kzalloc(sizeof(struct mmc_host) + extra, GFP_KERNEL); + if (!host) + return NULL; + + /* scanning will be enabled when we're ready */ + host->rescan_disable = 1; + + err = ida_simple_get(&mmc_host_ida, 0, 0, GFP_KERNEL); + if (err < 0) { + kfree(host); + return NULL; + } + + host->index = err; + + dev_set_name(&host->class_dev, "mmc%d", host->index); + + host->parent = dev; + host->class_dev.parent = dev; + host->class_dev.class = &mmc_host_class; + device_initialize(&host->class_dev); + device_enable_async_suspend(&host->class_dev); + + if (mmc_gpio_alloc(host)) { + put_device(&host->class_dev); + return NULL; + } + + spin_lock_init(&host->lock); + init_waitqueue_head(&host->wq); + INIT_DELAYED_WORK(&host->detect, mmc_rescan); + INIT_DELAYED_WORK(&host->sdio_irq_work, sdio_irq_work); + timer_setup(&host->retune_timer, mmc_retune_timer, 0); + + /* + * By default, hosts do not support SGIO or large requests. + * They have to set these according to their abilities. + */ + host->max_segs = 1; + host->max_seg_size = PAGE_SIZE; + + host->max_req_size = PAGE_SIZE; + host->max_blk_size = 512; + host->max_blk_count = PAGE_SIZE / 512; + + host->fixed_drv_type = -EINVAL; + host->ios.power_delay_ms = 10; + + return host; +} + +EXPORT_SYMBOL(mmc_alloc_host); + +static int mmc_validate_host_caps(struct mmc_host *host) +{ + if (host->caps & MMC_CAP_SDIO_IRQ && !host->ops->enable_sdio_irq) { + dev_warn(host->parent, "missing ->enable_sdio_irq() ops\n"); + return -EINVAL; + } + + return 0; +} + +/** + * mmc_add_host - initialise host hardware + * @host: mmc host + * + * Register the host with the driver model. The host must be + * prepared to start servicing requests before this function + * completes. + */ +int mmc_add_host(struct mmc_host *host) +{ + int err; + + err = mmc_validate_host_caps(host); + if (err) + return err; + + err = device_add(&host->class_dev); + if (err) + return err; + + led_trigger_register_simple(dev_name(&host->class_dev), &host->led); + +#ifdef CONFIG_DEBUG_FS + mmc_add_host_debugfs(host); +#endif + + mmc_start_host(host); + mmc_register_pm_notifier(host); + + return 0; +} + +EXPORT_SYMBOL(mmc_add_host); + +/** + * mmc_remove_host - remove host hardware + * @host: mmc host + * + * Unregister and remove all cards associated with this host, + * and power down the MMC bus. No new requests will be issued + * after this function has returned. + */ +void mmc_remove_host(struct mmc_host *host) +{ + mmc_unregister_pm_notifier(host); + mmc_stop_host(host); + +#ifdef CONFIG_DEBUG_FS + mmc_remove_host_debugfs(host); +#endif + + device_del(&host->class_dev); + + led_trigger_unregister_simple(host->led); +} + +EXPORT_SYMBOL(mmc_remove_host); + +/** + * mmc_free_host - free the host structure + * @host: mmc host + * + * Free the host once all references to it have been dropped. + */ +void mmc_free_host(struct mmc_host *host) +{ + mmc_pwrseq_free(host); + put_device(&host->class_dev); +} + +EXPORT_SYMBOL(mmc_free_host); |