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authorLinus Torvalds <torvalds@linux-foundation.org>2012-07-22 16:36:08 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2012-07-22 16:36:08 -0700
commita6be1fcbc57f95bb47ef3c8e4ee3d83731b8f21e (patch)
tree88d762edfd97e7cdb0b41b8fe20c1ddb204c28c9 /drivers/mmc/core/slot-gpio.c
parent5b160bd426946c85f32b15e5d34d62d2618a5a87 (diff)
parent30b87c60e9cbfcdfce22aa652fc1e5d061fcb733 (diff)
Merge tag 'mmc-merge-for-3.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc
Pull MMC updates from Chris Ball: "MMC highlights for 3.6: Core: - Rename cd-gpio to slot-gpio and extend it to support more slot GPIO functions, such as write-protect. - Add a function to get regulators (Vdd and Vccq) for a host. Drivers: - sdhci-pxav2, sdhci-pxav3: Add device tree support. - sdhi: Add device tree support. - sh_mmcif: Add support for regulators, device tree, slot-gpio. - tmio: Add regulator support, use slot-gpio." * tag 'mmc-merge-for-3.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc: (62 commits) mmc: sdhci-dove: Prepare for common clock framework mmc: sdhci-dove: Add SDHCI_QUIRK_NO_HISPD_BIT mmc: omap_hsmmc: ensure probe returns error upon resource failure mmc: mxs-mmc: Add wp-inverted property mmc: esdhc: Fix DMA_MASK to not break mx25 DMA access mmc: core: reset signal voltage on power up mmc: sd: Fix sd current limit setting mmc: omap_hsmmc: add clk_prepare and clk_unprepare mmc: sdhci: When a UHS switch fails, cycle power if regulator is used mmc: atmel-mci: modify CLKDIV displaying in debugfs mmc: atmel-mci: fix incorrect setting of host->data to NULL mmc: sdhci: poll for card even when card is logically unremovable mmc: sdhci: Introduce new flag SDHCI_USING_RETUNING_TIMER mmc: sdio: Change pr_warning to pr_warn_ratelimited mmc: core: Simplify and fix for SD switch processing mmc: sdhci: restore host settings when card is removed mmc: sdhci: fix incorrect command used in tuning mmc: sdhci-pci: CaFe has broken card detection mmc: sdhci: Report failure reasons for all cases in sdhci_add_host() mmc: s3cmci: Convert s3cmci driver to gpiolib API ...
Diffstat (limited to 'drivers/mmc/core/slot-gpio.c')
-rw-r--r--drivers/mmc/core/slot-gpio.c188
1 files changed, 188 insertions, 0 deletions
diff --git a/drivers/mmc/core/slot-gpio.c b/drivers/mmc/core/slot-gpio.c
new file mode 100644
index 000000000000..058242916cef
--- /dev/null
+++ b/drivers/mmc/core/slot-gpio.c
@@ -0,0 +1,188 @@
+/*
+ * Generic GPIO card-detect helper
+ *
+ * Copyright (C) 2011, Guennadi Liakhovetski <g.liakhovetski@gmx.de>
+ *
+ * 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/err.h>
+#include <linux/gpio.h>
+#include <linux/interrupt.h>
+#include <linux/jiffies.h>
+#include <linux/mmc/host.h>
+#include <linux/mmc/slot-gpio.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+
+struct mmc_gpio {
+ int ro_gpio;
+ int cd_gpio;
+ char *ro_label;
+ char cd_label[0];
+};
+
+static irqreturn_t mmc_gpio_cd_irqt(int irq, void *dev_id)
+{
+ /* Schedule a card detection after a debounce timeout */
+ mmc_detect_change(dev_id, msecs_to_jiffies(100));
+ 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) + 2 * len,
+ GFP_KERNEL);
+ if (ctx) {
+ ctx->ro_label = ctx->cd_label + len;
+ snprintf(ctx->cd_label, len, "%s cd", dev_name(host->parent));
+ snprintf(ctx->ro_label, len, "%s ro", dev_name(host->parent));
+ ctx->cd_gpio = -EINVAL;
+ ctx->ro_gpio = -EINVAL;
+ host->slot.handler_priv = ctx;
+ }
+ }
+
+ mutex_unlock(&host->slot.lock);
+
+ return ctx ? 0 : -ENOMEM;
+}
+
+int mmc_gpio_get_ro(struct mmc_host *host)
+{
+ struct mmc_gpio *ctx = host->slot.handler_priv;
+
+ if (!ctx || !gpio_is_valid(ctx->ro_gpio))
+ return -ENOSYS;
+
+ return !gpio_get_value_cansleep(ctx->ro_gpio) ^
+ !!(host->caps2 & MMC_CAP2_RO_ACTIVE_HIGH);
+}
+EXPORT_SYMBOL(mmc_gpio_get_ro);
+
+int mmc_gpio_get_cd(struct mmc_host *host)
+{
+ struct mmc_gpio *ctx = host->slot.handler_priv;
+
+ if (!ctx || !gpio_is_valid(ctx->cd_gpio))
+ return -ENOSYS;
+
+ return !gpio_get_value_cansleep(ctx->cd_gpio) ^
+ !!(host->caps2 & MMC_CAP2_CD_ACTIVE_HIGH);
+}
+EXPORT_SYMBOL(mmc_gpio_get_cd);
+
+int mmc_gpio_request_ro(struct mmc_host *host, unsigned int gpio)
+{
+ struct mmc_gpio *ctx;
+ int ret;
+
+ if (!gpio_is_valid(gpio))
+ return -EINVAL;
+
+ ret = mmc_gpio_alloc(host);
+ if (ret < 0)
+ return ret;
+
+ ctx = host->slot.handler_priv;
+
+ return gpio_request_one(gpio, GPIOF_DIR_IN, ctx->ro_label);
+}
+EXPORT_SYMBOL(mmc_gpio_request_ro);
+
+int mmc_gpio_request_cd(struct mmc_host *host, unsigned int gpio)
+{
+ struct mmc_gpio *ctx;
+ int irq = gpio_to_irq(gpio);
+ int ret;
+
+ ret = mmc_gpio_alloc(host);
+ if (ret < 0)
+ return ret;
+
+ ctx = host->slot.handler_priv;
+
+ ret = gpio_request_one(gpio, GPIOF_DIR_IN, ctx->cd_label);
+ if (ret < 0)
+ /*
+ * 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
+ * still prefer to poll, e.g., because that IRQ number is already used
+ * by another unit and cannot be shared.
+ */
+ if (irq >= 0 && host->caps & MMC_CAP_NEEDS_POLL)
+ irq = -EINVAL;
+
+ if (irq >= 0) {
+ ret = request_threaded_irq(irq, NULL, mmc_gpio_cd_irqt,
+ IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+ ctx->cd_label, host);
+ if (ret < 0)
+ irq = ret;
+ }
+
+ host->slot.cd_irq = irq;
+
+ if (irq < 0)
+ host->caps |= MMC_CAP_NEEDS_POLL;
+
+ ctx->cd_gpio = gpio;
+
+ return 0;
+}
+EXPORT_SYMBOL(mmc_gpio_request_cd);
+
+void mmc_gpio_free_ro(struct mmc_host *host)
+{
+ struct mmc_gpio *ctx = host->slot.handler_priv;
+ int gpio;
+
+ if (!ctx || !gpio_is_valid(ctx->ro_gpio))
+ return;
+
+ gpio = ctx->ro_gpio;
+ ctx->ro_gpio = -EINVAL;
+
+ gpio_free(gpio);
+}
+EXPORT_SYMBOL(mmc_gpio_free_ro);
+
+void mmc_gpio_free_cd(struct mmc_host *host)
+{
+ struct mmc_gpio *ctx = host->slot.handler_priv;
+ int gpio;
+
+ if (!ctx || !gpio_is_valid(ctx->cd_gpio))
+ return;
+
+ if (host->slot.cd_irq >= 0) {
+ free_irq(host->slot.cd_irq, host);
+ host->slot.cd_irq = -EINVAL;
+ }
+
+ gpio = ctx->cd_gpio;
+ ctx->cd_gpio = -EINVAL;
+
+ gpio_free(gpio);
+}
+EXPORT_SYMBOL(mmc_gpio_free_cd);