diff options
Diffstat (limited to 'drivers/mmc/core/host.c')
| -rw-r--r-- | drivers/mmc/core/host.c | 258 |
1 files changed, 237 insertions, 21 deletions
diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c index b3ac6c5bc5c..95cceae9694 100644 --- a/drivers/mmc/core/host.c +++ b/drivers/mmc/core/host.c @@ -15,13 +15,17 @@ #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" @@ -31,6 +35,7 @@ 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); } @@ -53,6 +58,27 @@ 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 @@ -113,23 +139,25 @@ static void mmc_host_clk_gate_delayed(struct mmc_host *host) static void mmc_host_clk_gate_work(struct work_struct *work) { struct mmc_host *host = container_of(work, struct mmc_host, - clk_gate_work); + clk_gate_work.work); mmc_host_clk_gate_delayed(host); } /** - * mmc_host_clk_ungate - ungate hardware MCI clocks + * 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_ungate(struct mmc_host *host) +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) { @@ -160,21 +188,18 @@ static bool mmc_host_may_gate_card(struct mmc_card *card) * gate the clock, because there is somebody out there that may still * be using it. */ - if (mmc_card_sdio(card)) - return false; - - return true; + return !(card->quirks & MMC_QUIRK_BROKEN_CLK_GATING); } /** - * mmc_host_clk_gate - gate off hardware MCI clocks + * 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_gate(struct mmc_host *host) +void mmc_host_clk_release(struct mmc_host *host) { unsigned long flags; @@ -182,7 +207,8 @@ void mmc_host_clk_gate(struct mmc_host *host) host->clk_requests--; if (mmc_host_may_gate_card(host->card) && !host->clk_requests) - schedule_work(&host->clk_gate_work); + schedule_delayed_work(&host->clk_gate_work, + msecs_to_jiffies(host->clkgate_delay)); spin_unlock_irqrestore(&host->clk_lock, flags); } @@ -215,8 +241,13 @@ 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_WORK(&host->clk_gate_work, mmc_host_clk_gate_work); + INIT_DELAYED_WORK(&host->clk_gate_work, mmc_host_clk_gate_work); spin_lock_init(&host->clk_lock); mutex_init(&host->clk_gate_mutex); } @@ -231,14 +262,25 @@ 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_work_sync(&host->clk_gate_work)) + if (cancel_delayed_work_sync(&host->clk_gate_work)) mmc_host_clk_gate_delayed(host); if (host->clk_gated) - mmc_host_clk_ungate(host); + 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) @@ -249,9 +291,177 @@ 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 @@ -263,17 +473,20 @@ struct mmc_host *mmc_alloc_host(int extra, struct device *dev) int err; struct mmc_host *host; - if (!idr_pre_get(&mmc_host_idr, GFP_KERNEL)) - return NULL; - 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_get_new(&mmc_host_idr, host, &host->index); + err = idr_alloc(&mmc_host_idr, host, 0, 0, GFP_NOWAIT); + if (err >= 0) + host->index = err; spin_unlock(&mmc_host_lock); - if (err) + idr_preload_end(); + if (err < 0) goto free; dev_set_name(&host->class_dev, "mmc%d", host->index); @@ -285,10 +498,12 @@ struct mmc_host *mmc_alloc_host(int extra, struct device *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); - INIT_DELAYED_WORK_DEFERRABLE(&host->disable, mmc_host_deeper_disable); #ifdef CONFIG_PM host->pm_notify.notifier_call = mmc_pm_notify; #endif @@ -328,15 +543,16 @@ int mmc_add_host(struct mmc_host *host) WARN_ON((host->caps & MMC_CAP_SDIO_IRQ) && !host->ops->enable_sdio_irq); - led_trigger_register_simple(dev_name(&host->class_dev), &host->led); - 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); |
