From a7d1a1ebd8f5858a812ac3d5fbbc178b4959a63b Mon Sep 17 00:00:00 2001 From: Guennadi Liakhovetski Date: Tue, 1 May 2012 16:51:38 +0200 Subject: [PATCH] mmc: core: convert slot functions to managed allocation This prepares for the addition of further slot functions. Signed-off-by: Guennadi Liakhovetski Signed-off-by: Chris Ball --- drivers/mmc/core/host.c | 2 ++ drivers/mmc/core/slot-gpio.c | 51 +++++++++++++++++++++++++++++++++----------- include/linux/mmc/host.h | 3 +++ 3 files changed, 43 insertions(+), 13 deletions(-) diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c index b8c5290..74cf29a 100644 --- a/drivers/mmc/core/host.c +++ b/drivers/mmc/core/host.c @@ -32,6 +32,7 @@ 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); } @@ -327,6 +328,7 @@ 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); diff --git a/drivers/mmc/core/slot-gpio.c b/drivers/mmc/core/slot-gpio.c index 92cba02..41689da 100644 --- a/drivers/mmc/core/slot-gpio.c +++ b/drivers/mmc/core/slot-gpio.c @@ -29,6 +29,34 @@ static irqreturn_t mmc_gpio_cd_irqt(int irq, void *dev_id) return IRQ_HANDLED; } +static int mmc_gpio_alloc(struct mmc_host *host) +{ + size_t len = strlen(dev_name(host->parent)) + 4; + struct mmc_gpio *ctx; + + mutex_lock(&host->slot.lock); + + ctx = host->slot.handler_priv; + if (!ctx) { + /* + * devm_kzalloc() can be called after device_initialize(), even + * before device_add(), i.e., between mmc_alloc_host() and + * mmc_add_host() + */ + ctx = devm_kzalloc(&host->class_dev, sizeof(*ctx) + len, + GFP_KERNEL); + if (ctx) { + snprintf(ctx->cd_label, len, "%s cd", dev_name(host->parent)); + ctx->cd_gpio = -EINVAL; + host->slot.handler_priv = ctx; + } + } + + mutex_unlock(&host->slot.lock); + + return ctx ? 0 : -ENOMEM; +} + int mmc_gpio_get_cd(struct mmc_host *host) { struct mmc_gpio *ctx = host->slot.handler_priv; @@ -43,20 +71,24 @@ EXPORT_SYMBOL(mmc_gpio_get_cd); int mmc_gpio_request_cd(struct mmc_host *host, unsigned int gpio) { - size_t len = strlen(dev_name(host->parent)) + 4; struct mmc_gpio *ctx; int irq = gpio_to_irq(gpio); int ret; - ctx = kmalloc(sizeof(*ctx) + len, GFP_KERNEL); - if (!ctx) - return -ENOMEM; + ret = mmc_gpio_alloc(host); + if (ret < 0) + return ret; - snprintf(ctx->cd_label, len, "%s cd", dev_name(host->parent)); + ctx = host->slot.handler_priv; ret = gpio_request_one(gpio, GPIOF_DIR_IN, ctx->cd_label); if (ret < 0) - goto egpioreq; + /* + * don't bother freeing memory. It might still get used by other + * slot functions, in any case it will be freed, when the device + * is destroyed. + */ + return ret; /* * Even if gpio_to_irq() returns a valid IRQ number, the platform might @@ -80,13 +112,8 @@ int mmc_gpio_request_cd(struct mmc_host *host, unsigned int gpio) host->caps |= MMC_CAP_NEEDS_POLL; ctx->cd_gpio = gpio; - host->slot.handler_priv = ctx; return 0; - -egpioreq: - kfree(ctx); - return ret; } EXPORT_SYMBOL(mmc_gpio_request_cd); @@ -107,7 +134,5 @@ void mmc_gpio_free_cd(struct mmc_host *host) ctx->cd_gpio = -EINVAL; gpio_free(gpio); - host->slot.handler_priv = NULL; - kfree(ctx); } EXPORT_SYMBOL(mmc_gpio_free_cd); diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h index c1a03ee..65c64ee 100644 --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -11,6 +11,7 @@ #define LINUX_MMC_HOST_H #include +#include #include #include #include @@ -154,6 +155,7 @@ struct mmc_async_req { * struct mmc_slot - MMC slot functions * * @cd_irq: MMC/SD-card slot hotplug detection IRQ or -EINVAL + * @lock: protect the @handler_priv pointer * @handler_priv: MMC/SD-card slot context * * Some MMC/SD host controllers implement slot-functions like card and @@ -163,6 +165,7 @@ struct mmc_async_req { */ struct mmc_slot { int cd_irq; + struct mutex lock; void *handler_priv; }; -- 2.7.4