diff options
Diffstat (limited to 'drivers/mmc/core/core.c')
| -rw-r--r-- | drivers/mmc/core/core.c | 727 |
1 files changed, 727 insertions, 0 deletions
diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c new file mode 100644 index 000000000000..72c7cf4a9f9d --- /dev/null +++ b/drivers/mmc/core/core.c @@ -0,0 +1,727 @@ +/* + * linux/drivers/mmc/core/core.c + * + * Copyright (C) 2003-2004 Russell King, All Rights Reserved. + * SD support Copyright (C) 2004 Ian Molton, All Rights Reserved. + * Copyright (C) 2005-2007 Pierre Ossman, All Rights Reserved. + * MMCv4 support Copyright (C) 2006 Philip Langdale, All Rights Reserved. + * + * 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/module.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/completion.h> +#include <linux/device.h> +#include <linux/delay.h> +#include <linux/pagemap.h> +#include <linux/err.h> +#include <asm/scatterlist.h> +#include <linux/scatterlist.h> + +#include <linux/mmc/card.h> +#include <linux/mmc/host.h> +#include <linux/mmc/mmc.h> +#include <linux/mmc/sd.h> + +#include "core.h" +#include "sysfs.h" + +#include "mmc_ops.h" +#include "sd_ops.h" + +extern int mmc_attach_mmc(struct mmc_host *host, u32 ocr); +extern int mmc_attach_sd(struct mmc_host *host, u32 ocr); + +/** + * mmc_request_done - finish processing an MMC request + * @host: MMC host which completed request + * @mrq: MMC request which request + * + * MMC drivers should call this function when they have completed + * their processing of a request. + */ +void mmc_request_done(struct mmc_host *host, struct mmc_request *mrq) +{ + struct mmc_command *cmd = mrq->cmd; + int err = cmd->error; + + pr_debug("%s: req done (CMD%u): %d/%d/%d: %08x %08x %08x %08x\n", + mmc_hostname(host), cmd->opcode, err, + mrq->data ? mrq->data->error : 0, + mrq->stop ? mrq->stop->error : 0, + cmd->resp[0], cmd->resp[1], cmd->resp[2], cmd->resp[3]); + + if (err && cmd->retries) { + cmd->retries--; + cmd->error = 0; + host->ops->request(host, mrq); + } else if (mrq->done) { + mrq->done(mrq); + } +} + +EXPORT_SYMBOL(mmc_request_done); + +/** + * mmc_start_request - start a command on a host + * @host: MMC host to start command on + * @mrq: MMC request to start + * + * Queue a command on the specified host. We expect the + * caller to be holding the host lock with interrupts disabled. + */ +void +mmc_start_request(struct mmc_host *host, struct mmc_request *mrq) +{ +#ifdef CONFIG_MMC_DEBUG + unsigned int i, sz; +#endif + + pr_debug("%s: starting CMD%u arg %08x flags %08x\n", + mmc_hostname(host), mrq->cmd->opcode, + mrq->cmd->arg, mrq->cmd->flags); + + WARN_ON(!host->claimed); + + mrq->cmd->error = 0; + mrq->cmd->mrq = mrq; + if (mrq->data) { + BUG_ON(mrq->data->blksz > host->max_blk_size); + BUG_ON(mrq->data->blocks > host->max_blk_count); + BUG_ON(mrq->data->blocks * mrq->data->blksz > + host->max_req_size); + +#ifdef CONFIG_MMC_DEBUG + sz = 0; + for (i = 0;i < mrq->data->sg_len;i++) + sz += mrq->data->sg[i].length; + BUG_ON(sz != mrq->data->blocks * mrq->data->blksz); +#endif + + mrq->cmd->data = mrq->data; + mrq->data->error = 0; + mrq->data->mrq = mrq; + if (mrq->stop) { + mrq->data->stop = mrq->stop; + mrq->stop->error = 0; + mrq->stop->mrq = mrq; + } + } + host->ops->request(host, mrq); +} + +EXPORT_SYMBOL(mmc_start_request); + +static void mmc_wait_done(struct mmc_request *mrq) +{ + complete(mrq->done_data); +} + +int mmc_wait_for_req(struct mmc_host *host, struct mmc_request *mrq) +{ + DECLARE_COMPLETION_ONSTACK(complete); + + mrq->done_data = &complete; + mrq->done = mmc_wait_done; + + mmc_start_request(host, mrq); + + wait_for_completion(&complete); + + return 0; +} + +EXPORT_SYMBOL(mmc_wait_for_req); + +/** + * mmc_wait_for_cmd - start a command and wait for completion + * @host: MMC host to start command + * @cmd: MMC command to start + * @retries: maximum number of retries + * + * Start a new MMC command for a host, and wait for the command + * to complete. Return any error that occurred while the command + * was executing. Do not attempt to parse the response. + */ +int mmc_wait_for_cmd(struct mmc_host *host, struct mmc_command *cmd, int retries) +{ + struct mmc_request mrq; + + BUG_ON(!host->claimed); + + memset(&mrq, 0, sizeof(struct mmc_request)); + + memset(cmd->resp, 0, sizeof(cmd->resp)); + cmd->retries = retries; + + mrq.cmd = cmd; + cmd->data = NULL; + + mmc_wait_for_req(host, &mrq); + + return cmd->error; +} + +EXPORT_SYMBOL(mmc_wait_for_cmd); + +/** + * mmc_set_data_timeout - set the timeout for a data command + * @data: data phase for command + * @card: the MMC card associated with the data transfer + * @write: flag to differentiate reads from writes + */ +void mmc_set_data_timeout(struct mmc_data *data, const struct mmc_card *card, + int write) +{ + unsigned int mult; + + /* + * SD cards use a 100 multiplier rather than 10 + */ + mult = mmc_card_sd(card) ? 100 : 10; + + /* + * Scale up the multiplier (and therefore the timeout) by + * the r2w factor for writes. + */ + if (write) + mult <<= card->csd.r2w_factor; + + data->timeout_ns = card->csd.tacc_ns * mult; + data->timeout_clks = card->csd.tacc_clks * mult; + + /* + * SD cards also have an upper limit on the timeout. + */ + if (mmc_card_sd(card)) { + unsigned int timeout_us, limit_us; + + timeout_us = data->timeout_ns / 1000; + timeout_us += data->timeout_clks * 1000 / + (card->host->ios.clock / 1000); + + if (write) + limit_us = 250000; + else + limit_us = 100000; + + /* + * SDHC cards always use these fixed values. + */ + if (timeout_us > limit_us || mmc_card_blockaddr(card)) { + data->timeout_ns = limit_us * 1000; + data->timeout_clks = 0; + } + } +} +EXPORT_SYMBOL(mmc_set_data_timeout); + +/** + * __mmc_claim_host - exclusively claim a host + * @host: mmc host to claim + * @card: mmc card to claim host for + * + * Claim a host for a set of operations. If a valid card + * is passed and this wasn't the last card selected, select + * the card before returning. + * + * Note: you should use mmc_card_claim_host or mmc_claim_host. + */ +void mmc_claim_host(struct mmc_host *host) +{ + DECLARE_WAITQUEUE(wait, current); + unsigned long flags; + + add_wait_queue(&host->wq, &wait); + spin_lock_irqsave(&host->lock, flags); + while (1) { + set_current_state(TASK_UNINTERRUPTIBLE); + if (!host->claimed) + break; + spin_unlock_irqrestore(&host->lock, flags); + schedule(); + spin_lock_irqsave(&host->lock, flags); + } + set_current_state(TASK_RUNNING); + host->claimed = 1; + spin_unlock_irqrestore(&host->lock, flags); + remove_wait_queue(&host->wq, &wait); +} + +EXPORT_SYMBOL(mmc_claim_host); + +/** + * mmc_release_host - release a host + * @host: mmc host to release + * + * Release a MMC host, allowing others to claim the host + * for their operations. + */ +void mmc_release_host(struct mmc_host *host) +{ + unsigned long flags; + + BUG_ON(!host->claimed); + + spin_lock_irqsave(&host->lock, flags); + host->claimed = 0; + spin_unlock_irqrestore(&host->lock, flags); + + wake_up(&host->wq); +} + +EXPORT_SYMBOL(mmc_release_host); + +/* + * Internal function that does the actual ios call to the host driver, + * optionally printing some debug output. + */ +static inline void mmc_set_ios(struct mmc_host *host) +{ + struct mmc_ios *ios = &host->ios; + + pr_debug("%s: clock %uHz busmode %u powermode %u cs %u Vdd %u " + "width %u timing %u\n", + mmc_hostname(host), ios->clock, ios->bus_mode, + ios->power_mode, ios->chip_select, ios->vdd, + ios->bus_width, ios->timing); + + host->ops->set_ios(host, ios); +} + +/* + * Control chip select pin on a host. + */ +void mmc_set_chip_select(struct mmc_host *host, int mode) +{ + host->ios.chip_select = mode; + mmc_set_ios(host); +} + +/* + * Sets the host clock to the highest possible frequency that + * is below "hz". + */ +void mmc_set_clock(struct mmc_host *host, unsigned int hz) +{ + WARN_ON(hz < host->f_min); + + if (hz > host->f_max) + hz = host->f_max; + + host->ios.clock = hz; + mmc_set_ios(host); +} + +/* + * Change the bus mode (open drain/push-pull) of a host. + */ +void mmc_set_bus_mode(struct mmc_host *host, unsigned int mode) +{ + host->ios.bus_mode = mode; + mmc_set_ios(host); +} + +/* + * Change data bus width of a host. + */ +void mmc_set_bus_width(struct mmc_host *host, unsigned int width) +{ + host->ios.bus_width = width; + mmc_set_ios(host); +} + +/* + * Mask off any voltages we don't support and select + * the lowest voltage + */ +u32 mmc_select_voltage(struct mmc_host *host, u32 ocr) +{ + int bit; + + ocr &= host->ocr_avail; + + bit = ffs(ocr); + if (bit) { + bit -= 1; + + ocr &= 3 << bit; + + host->ios.vdd = bit; + mmc_set_ios(host); + } else { + ocr = 0; + } + + return ocr; +} + +/* + * Select timing parameters for host. + */ +void mmc_set_timing(struct mmc_host *host, unsigned int timing) +{ + host->ios.timing = timing; + mmc_set_ios(host); +} + +/* + * Allocate a new MMC card + */ +struct mmc_card *mmc_alloc_card(struct mmc_host *host) +{ + struct mmc_card *card; + + card = kmalloc(sizeof(struct mmc_card), GFP_KERNEL); + if (!card) + return ERR_PTR(-ENOMEM); + + mmc_init_card(card, host); + + return card; +} + +/* + * Apply power to the MMC stack. This is a two-stage process. + * First, we enable power to the card without the clock running. + * We then wait a bit for the power to stabilise. Finally, + * enable the bus drivers and clock to the card. + * + * We must _NOT_ enable the clock prior to power stablising. + * + * If a host does all the power sequencing itself, ignore the + * initial MMC_POWER_UP stage. + */ +static void mmc_power_up(struct mmc_host *host) +{ + int bit = fls(host->ocr_avail) - 1; + + host->ios.vdd = bit; + host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN; + host->ios.chip_select = MMC_CS_DONTCARE; + host->ios.power_mode = MMC_POWER_UP; + host->ios.bus_width = MMC_BUS_WIDTH_1; + host->ios.timing = MMC_TIMING_LEGACY; + mmc_set_ios(host); + + mmc_delay(1); + + host->ios.clock = host->f_min; + host->ios.power_mode = MMC_POWER_ON; + mmc_set_ios(host); + + mmc_delay(2); +} + +static void mmc_power_off(struct mmc_host *host) +{ + host->ios.clock = 0; + host->ios.vdd = 0; + host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN; + host->ios.chip_select = MMC_CS_DONTCARE; + host->ios.power_mode = MMC_POWER_OFF; + host->ios.bus_width = MMC_BUS_WIDTH_1; + host->ios.timing = MMC_TIMING_LEGACY; + mmc_set_ios(host); +} + +/* + * Assign a mmc bus handler to a host. Only one bus handler may control a + * host at any given time. + */ +void mmc_attach_bus(struct mmc_host *host, const struct mmc_bus_ops *ops) +{ + unsigned long flags; + + BUG_ON(!host); + BUG_ON(!ops); + + BUG_ON(!host->claimed); + + spin_lock_irqsave(&host->lock, flags); + + BUG_ON(host->bus_ops); + BUG_ON(host->bus_refs); + + host->bus_ops = ops; + host->bus_refs = 1; + host->bus_dead = 0; + + spin_unlock_irqrestore(&host->lock, flags); +} + +/* + * Remove the current bus handler from a host. Assumes that there are + * no interesting cards left, so the bus is powered down. + */ +void mmc_detach_bus(struct mmc_host *host) +{ + unsigned long flags; + + BUG_ON(!host); + + BUG_ON(!host->claimed); + BUG_ON(!host->bus_ops); + + spin_lock_irqsave(&host->lock, flags); + + host->bus_dead = 1; + + spin_unlock_irqrestore(&host->lock, flags); + + mmc_power_off(host); + + mmc_bus_put(host); +} + +/* + * Cleanup when the last reference to the bus operator is dropped. + */ +void __mmc_release_bus(struct mmc_host *host) +{ + BUG_ON(!host); + BUG_ON(host->bus_refs); + BUG_ON(!host->bus_dead); + + host->bus_ops = NULL; +} + +/** + * mmc_detect_change - process change of state on a MMC socket + * @host: host which changed state. + * @delay: optional delay to wait before detection (jiffies) + * + * All we know is that card(s) have been inserted or removed + * from the socket(s). We don't know which socket or cards. + */ +void mmc_detect_change(struct mmc_host *host, unsigned long delay) +{ +#ifdef CONFIG_MMC_DEBUG + mmc_claim_host(host); + BUG_ON(host->removed); + mmc_release_host(host); +#endif + + mmc_schedule_delayed_work(&host->detect, delay); +} + +EXPORT_SYMBOL(mmc_detect_change); + + +static void mmc_rescan(struct work_struct *work) +{ + struct mmc_host *host = + container_of(work, struct mmc_host, detect.work); + u32 ocr; + int err; + + mmc_bus_get(host); + + if (host->bus_ops == NULL) { + /* + * Only we can add a new handler, so it's safe to + * release the lock here. + */ + mmc_bus_put(host); + + mmc_claim_host(host); + + mmc_power_up(host); + mmc_go_idle(host); + + mmc_send_if_cond(host, host->ocr_avail); + + err = mmc_send_app_op_cond(host, 0, &ocr); + if (err == MMC_ERR_NONE) { + if (mmc_attach_sd(host, ocr)) + mmc_power_off(host); + } else { + /* + * If we fail to detect any SD cards then try + * searching for MMC cards. + */ + err = mmc_send_op_cond(host, 0, &ocr); + if (err == MMC_ERR_NONE) { + if (mmc_attach_mmc(host, ocr)) + mmc_power_off(host); + } else { + mmc_power_off(host); + mmc_release_host(host); + } + } + } else { + if (host->bus_ops->detect && !host->bus_dead) + host->bus_ops->detect(host); + + mmc_bus_put(host); + } +} + + +/** + * 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) +{ + struct mmc_host *host; + + host = mmc_alloc_host_sysfs(extra, dev); + if (host) { + spin_lock_init(&host->lock); + init_waitqueue_head(&host->wq); + INIT_DELAYED_WORK(&host->detect, mmc_rescan); + + /* + * By default, hosts do not support SGIO or large requests. + * They have to set these according to their abilities. + */ + host->max_hw_segs = 1; + host->max_phys_segs = 1; + host->max_seg_size = PAGE_CACHE_SIZE; + + host->max_req_size = PAGE_CACHE_SIZE; + host->max_blk_size = 512; + host->max_blk_count = PAGE_CACHE_SIZE / 512; + } + + return host; +} + +EXPORT_SYMBOL(mmc_alloc_host); + +/** + * mmc_add_host - initialise host hardware + * @host: mmc host + */ +int mmc_add_host(struct mmc_host *host) +{ + int ret; + + ret = mmc_add_host_sysfs(host); + if (ret == 0) { + mmc_power_off(host); + mmc_detect_change(host, 0); + } + + return ret; +} + +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. + */ +void mmc_remove_host(struct mmc_host *host) +{ +#ifdef CONFIG_MMC_DEBUG + mmc_claim_host(host); + host->removed = 1; + mmc_release_host(host); +#endif + + mmc_flush_scheduled_work(); + + mmc_bus_get(host); + if (host->bus_ops && !host->bus_dead) { + if (host->bus_ops->remove) + host->bus_ops->remove(host); + + mmc_claim_host(host); + mmc_detach_bus(host); + mmc_release_host(host); + } + mmc_bus_put(host); + + BUG_ON(host->card); + + mmc_power_off(host); + mmc_remove_host_sysfs(host); +} + +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_free_host_sysfs(host); +} + +EXPORT_SYMBOL(mmc_free_host); + +#ifdef CONFIG_PM + +/** + * mmc_suspend_host - suspend a host + * @host: mmc host + * @state: suspend mode (PM_SUSPEND_xxx) + */ +int mmc_suspend_host(struct mmc_host *host, pm_message_t state) +{ + mmc_flush_scheduled_work(); + + mmc_bus_get(host); + if (host->bus_ops && !host->bus_dead) { + if (host->bus_ops->suspend) + host->bus_ops->suspend(host); + if (!host->bus_ops->resume) { + if (host->bus_ops->remove) + host->bus_ops->remove(host); + + mmc_claim_host(host); + mmc_detach_bus(host); + mmc_release_host(host); + } + } + mmc_bus_put(host); + + mmc_power_off(host); + + return 0; +} + +EXPORT_SYMBOL(mmc_suspend_host); + +/** + * mmc_resume_host - resume a previously suspended host + * @host: mmc host + */ +int mmc_resume_host(struct mmc_host *host) +{ + mmc_bus_get(host); + if (host->bus_ops && !host->bus_dead) { + mmc_power_up(host); + BUG_ON(!host->bus_ops->resume); + host->bus_ops->resume(host); + } + mmc_bus_put(host); + + /* + * We add a slight delay here so that resume can progress + * in parallel. + */ + mmc_detect_change(host, 1); + + return 0; +} + +EXPORT_SYMBOL(mmc_resume_host); + +#endif + +MODULE_LICENSE("GPL"); |