kernel_optimize_test/drivers/mmc/core/host.c
Seungwon Jeon c373eb489b mmc: core: add DT bindings for eMMC HS400 1.8/1.2V
Provide the option to configure these speed modes per host,
for those host driver's that can't distinguish this in runtime.
Specially, if host can support HS400, it means that host can also
support HS200.

Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <chris@printf.net>
2014-05-12 18:08:10 -04:00

607 lines
16 KiB
C

/*
* 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/suspend.h>
#include <linux/mmc/host.h>
#include <linux/mmc/card.h>
#include <linux/mmc/slot-gpio.h>
#include "core.h"
#include "host.h"
#define cls_dev_to_mmc_host(d) container_of(d, struct mmc_host, class_dev)
static void mmc_host_classdev_release(struct device *dev)
{
struct mmc_host *host = cls_dev_to_mmc_host(dev);
mutex_destroy(&host->slot.lock);
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);
}
static DEFINE_IDR(mmc_host_idr);
static DEFINE_SPINLOCK(mmc_host_lock);
#ifdef CONFIG_MMC_CLKGATE
static ssize_t clkgate_delay_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct mmc_host *host = cls_dev_to_mmc_host(dev);
return snprintf(buf, PAGE_SIZE, "%lu\n", host->clkgate_delay);
}
static ssize_t clkgate_delay_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
struct mmc_host *host = cls_dev_to_mmc_host(dev);
unsigned long flags, value;
if (kstrtoul(buf, 0, &value))
return -EINVAL;
spin_lock_irqsave(&host->clk_lock, flags);
host->clkgate_delay = value;
spin_unlock_irqrestore(&host->clk_lock, flags);
return count;
}
/*
* Enabling clock gating will make the core call out to the host
* once up and once down when it performs a request or card operation
* intermingled in any fashion. The driver will see this through
* set_ios() operations with ios.clock field set to 0 to gate (disable)
* the block clock, and to the old frequency to enable it again.
*/
static void mmc_host_clk_gate_delayed(struct mmc_host *host)
{
unsigned long tick_ns;
unsigned long freq = host->ios.clock;
unsigned long flags;
if (!freq) {
pr_debug("%s: frequency set to 0 in disable function, "
"this means the clock is already disabled.\n",
mmc_hostname(host));
return;
}
/*
* New requests may have appeared while we were scheduling,
* then there is no reason to delay the check before
* clk_disable().
*/
spin_lock_irqsave(&host->clk_lock, flags);
/*
* Delay n bus cycles (at least 8 from MMC spec) before attempting
* to disable the MCI block clock. The reference count may have
* gone up again after this delay due to rescheduling!
*/
if (!host->clk_requests) {
spin_unlock_irqrestore(&host->clk_lock, flags);
tick_ns = DIV_ROUND_UP(1000000000, freq);
ndelay(host->clk_delay * tick_ns);
} else {
/* New users appeared while waiting for this work */
spin_unlock_irqrestore(&host->clk_lock, flags);
return;
}
mutex_lock(&host->clk_gate_mutex);
spin_lock_irqsave(&host->clk_lock, flags);
if (!host->clk_requests) {
spin_unlock_irqrestore(&host->clk_lock, flags);
/* This will set host->ios.clock to 0 */
mmc_gate_clock(host);
spin_lock_irqsave(&host->clk_lock, flags);
pr_debug("%s: gated MCI clock\n", mmc_hostname(host));
}
spin_unlock_irqrestore(&host->clk_lock, flags);
mutex_unlock(&host->clk_gate_mutex);
}
/*
* Internal work. Work to disable the clock at some later point.
*/
static void mmc_host_clk_gate_work(struct work_struct *work)
{
struct mmc_host *host = container_of(work, struct mmc_host,
clk_gate_work.work);
mmc_host_clk_gate_delayed(host);
}
/**
* mmc_host_clk_hold - ungate hardware MCI clocks
* @host: host to ungate.
*
* Makes sure the host ios.clock is restored to a non-zero value
* past this call. Increase clock reference count and ungate clock
* if we're the first user.
*/
void mmc_host_clk_hold(struct mmc_host *host)
{
unsigned long flags;
/* cancel any clock gating work scheduled by mmc_host_clk_release() */
cancel_delayed_work_sync(&host->clk_gate_work);
mutex_lock(&host->clk_gate_mutex);
spin_lock_irqsave(&host->clk_lock, flags);
if (host->clk_gated) {
spin_unlock_irqrestore(&host->clk_lock, flags);
mmc_ungate_clock(host);
spin_lock_irqsave(&host->clk_lock, flags);
pr_debug("%s: ungated MCI clock\n", mmc_hostname(host));
}
host->clk_requests++;
spin_unlock_irqrestore(&host->clk_lock, flags);
mutex_unlock(&host->clk_gate_mutex);
}
/**
* mmc_host_may_gate_card - check if this card may be gated
* @card: card to check.
*/
static bool mmc_host_may_gate_card(struct mmc_card *card)
{
/* If there is no card we may gate it */
if (!card)
return true;
/*
* Don't gate SDIO cards! These need to be clocked at all times
* since they may be independent systems generating interrupts
* and other events. The clock requests counter from the core will
* go down to zero since the core does not need it, but we will not
* gate the clock, because there is somebody out there that may still
* be using it.
*/
return !(card->quirks & MMC_QUIRK_BROKEN_CLK_GATING);
}
/**
* mmc_host_clk_release - gate off hardware MCI clocks
* @host: host to gate.
*
* Calls the host driver with ios.clock set to zero as often as possible
* in order to gate off hardware MCI clocks. Decrease clock reference
* count and schedule disabling of clock.
*/
void mmc_host_clk_release(struct mmc_host *host)
{
unsigned long flags;
spin_lock_irqsave(&host->clk_lock, flags);
host->clk_requests--;
if (mmc_host_may_gate_card(host->card) &&
!host->clk_requests)
schedule_delayed_work(&host->clk_gate_work,
msecs_to_jiffies(host->clkgate_delay));
spin_unlock_irqrestore(&host->clk_lock, flags);
}
/**
* mmc_host_clk_rate - get current clock frequency setting
* @host: host to get the clock frequency for.
*
* Returns current clock frequency regardless of gating.
*/
unsigned int mmc_host_clk_rate(struct mmc_host *host)
{
unsigned long freq;
unsigned long flags;
spin_lock_irqsave(&host->clk_lock, flags);
if (host->clk_gated)
freq = host->clk_old;
else
freq = host->ios.clock;
spin_unlock_irqrestore(&host->clk_lock, flags);
return freq;
}
/**
* mmc_host_clk_init - set up clock gating code
* @host: host with potential clock to control
*/
static inline void mmc_host_clk_init(struct mmc_host *host)
{
host->clk_requests = 0;
/* Hold MCI clock for 8 cycles by default */
host->clk_delay = 8;
/*
* Default clock gating delay is 0ms to avoid wasting power.
* This value can be tuned by writing into sysfs entry.
*/
host->clkgate_delay = 0;
host->clk_gated = false;
INIT_DELAYED_WORK(&host->clk_gate_work, mmc_host_clk_gate_work);
spin_lock_init(&host->clk_lock);
mutex_init(&host->clk_gate_mutex);
}
/**
* mmc_host_clk_exit - shut down clock gating code
* @host: host with potential clock to control
*/
static inline void mmc_host_clk_exit(struct mmc_host *host)
{
/*
* Wait for any outstanding gate and then make sure we're
* ungated before exiting.
*/
if (cancel_delayed_work_sync(&host->clk_gate_work))
mmc_host_clk_gate_delayed(host);
if (host->clk_gated)
mmc_host_clk_hold(host);
/* There should be only one user now */
WARN_ON(host->clk_requests > 1);
}
static inline void mmc_host_clk_sysfs_init(struct mmc_host *host)
{
host->clkgate_delay_attr.show = clkgate_delay_show;
host->clkgate_delay_attr.store = clkgate_delay_store;
sysfs_attr_init(&host->clkgate_delay_attr.attr);
host->clkgate_delay_attr.attr.name = "clkgate_delay";
host->clkgate_delay_attr.attr.mode = S_IRUGO | S_IWUSR;
if (device_create_file(&host->class_dev, &host->clkgate_delay_attr))
pr_err("%s: Failed to create clkgate_delay sysfs entry\n",
mmc_hostname(host));
}
#else
static inline void mmc_host_clk_init(struct mmc_host *host)
{
}
static inline void mmc_host_clk_exit(struct mmc_host *host)
{
}
static inline void mmc_host_clk_sysfs_init(struct mmc_host *host)
{
}
#endif
/**
* 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_node *np;
u32 bus_width;
bool explicit_inv_wp, gpio_inv_wp = false;
enum of_gpio_flags flags;
int len, ret, gpio;
if (!host->parent || !host->parent->of_node)
return 0;
np = host->parent->of_node;
/* "bus-width" is translated to MMC_CAP_*_BIT_DATA flags */
if (of_property_read_u32(np, "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 */
of_property_read_u32(np, "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 (of_find_property(np, "non-removable", &len)) {
host->caps |= MMC_CAP_NONREMOVABLE;
} else {
bool explicit_inv_cd, gpio_inv_cd = false;
explicit_inv_cd = of_property_read_bool(np, "cd-inverted");
if (of_find_property(np, "broken-cd", &len))
host->caps |= MMC_CAP_NEEDS_POLL;
gpio = of_get_named_gpio_flags(np, "cd-gpios", 0, &flags);
if (gpio == -EPROBE_DEFER)
return gpio;
if (gpio_is_valid(gpio)) {
if (!(flags & OF_GPIO_ACTIVE_LOW))
gpio_inv_cd = true;
ret = mmc_gpio_request_cd(host, gpio, 0);
if (ret < 0) {
dev_err(host->parent,
"Failed to request CD GPIO #%d: %d!\n",
gpio, ret);
return ret;
} else {
dev_info(host->parent, "Got CD GPIO #%d.\n",
gpio);
}
}
if (explicit_inv_cd ^ gpio_inv_cd)
host->caps2 |= MMC_CAP2_CD_ACTIVE_HIGH;
}
/* Parse Write Protection */
explicit_inv_wp = of_property_read_bool(np, "wp-inverted");
gpio = of_get_named_gpio_flags(np, "wp-gpios", 0, &flags);
if (gpio == -EPROBE_DEFER) {
ret = -EPROBE_DEFER;
goto out;
}
if (gpio_is_valid(gpio)) {
if (!(flags & OF_GPIO_ACTIVE_LOW))
gpio_inv_wp = true;
ret = mmc_gpio_request_ro(host, gpio);
if (ret < 0) {
dev_err(host->parent,
"Failed to request WP GPIO: %d!\n", ret);
goto out;
} else {
dev_info(host->parent, "Got WP GPIO #%d.\n",
gpio);
}
}
if (explicit_inv_wp ^ gpio_inv_wp)
host->caps2 |= MMC_CAP2_RO_ACTIVE_HIGH;
if (of_find_property(np, "cap-sd-highspeed", &len))
host->caps |= MMC_CAP_SD_HIGHSPEED;
if (of_find_property(np, "cap-mmc-highspeed", &len))
host->caps |= MMC_CAP_MMC_HIGHSPEED;
if (of_find_property(np, "sd-uhs-sdr12", &len))
host->caps |= MMC_CAP_UHS_SDR12;
if (of_find_property(np, "sd-uhs-sdr25", &len))
host->caps |= MMC_CAP_UHS_SDR25;
if (of_find_property(np, "sd-uhs-sdr50", &len))
host->caps |= MMC_CAP_UHS_SDR50;
if (of_find_property(np, "sd-uhs-sdr104", &len))
host->caps |= MMC_CAP_UHS_SDR104;
if (of_find_property(np, "sd-uhs-ddr50", &len))
host->caps |= MMC_CAP_UHS_DDR50;
if (of_find_property(np, "cap-power-off-card", &len))
host->caps |= MMC_CAP_POWER_OFF_CARD;
if (of_find_property(np, "cap-sdio-irq", &len))
host->caps |= MMC_CAP_SDIO_IRQ;
if (of_find_property(np, "full-pwr-cycle", &len))
host->caps2 |= MMC_CAP2_FULL_PWR_CYCLE;
if (of_find_property(np, "keep-power-in-suspend", &len))
host->pm_caps |= MMC_PM_KEEP_POWER;
if (of_find_property(np, "enable-sdio-wakeup", &len))
host->pm_caps |= MMC_PM_WAKE_SDIO_IRQ;
if (of_find_property(np, "mmc-ddr-1_8v", &len))
host->caps |= MMC_CAP_1_8V_DDR;
if (of_find_property(np, "mmc-ddr-1_2v", &len))
host->caps |= MMC_CAP_1_2V_DDR;
if (of_find_property(np, "mmc-hs200-1_8v", &len))
host->caps2 |= MMC_CAP2_HS200_1_8V_SDR;
if (of_find_property(np, "mmc-hs200-1_2v", &len))
host->caps2 |= MMC_CAP2_HS200_1_2V_SDR;
if (of_find_property(np, "mmc-hs400-1_8v", &len))
host->caps2 |= MMC_CAP2_HS400_1_8V | MMC_CAP2_HS200_1_8V_SDR;
if (of_find_property(np, "mmc-hs400-1_2v", &len))
host->caps2 |= MMC_CAP2_HS400_1_2V | MMC_CAP2_HS200_1_2V_SDR;
return 0;
out:
mmc_gpio_free_cd(host);
return ret;
}
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;
idr_preload(GFP_KERNEL);
spin_lock(&mmc_host_lock);
err = idr_alloc(&mmc_host_idr, host, 0, 0, GFP_NOWAIT);
if (err >= 0)
host->index = err;
spin_unlock(&mmc_host_lock);
idr_preload_end();
if (err < 0)
goto free;
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);
mmc_host_clk_init(host);
mutex_init(&host->slot.lock);
host->slot.cd_irq = -EINVAL;
spin_lock_init(&host->lock);
init_waitqueue_head(&host->wq);
INIT_DELAYED_WORK(&host->detect, mmc_rescan);
#ifdef CONFIG_PM
host->pm_notify.notifier_call = mmc_pm_notify;
#endif
/*
* 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_CACHE_SIZE;
host->max_req_size = PAGE_CACHE_SIZE;
host->max_blk_size = 512;
host->max_blk_count = PAGE_CACHE_SIZE / 512;
return host;
free:
kfree(host);
return NULL;
}
EXPORT_SYMBOL(mmc_alloc_host);
/**
* 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;
WARN_ON((host->caps & MMC_CAP_SDIO_IRQ) &&
!host->ops->enable_sdio_irq);
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_host_clk_sysfs_init(host);
mmc_start_host(host);
register_pm_notifier(&host->pm_notify);
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)
{
unregister_pm_notifier(&host->pm_notify);
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);
mmc_host_clk_exit(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)
{
spin_lock(&mmc_host_lock);
idr_remove(&mmc_host_idr, host->index);
spin_unlock(&mmc_host_lock);
put_device(&host->class_dev);
}
EXPORT_SYMBOL(mmc_free_host);