sdhci-spear: ST SPEAr based SDHCI controller glue

Add a glue layer to support the sdhci driver on the ST SPEAr platform.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Cc: <shiraz.hashim@st.com>
Cc: Linus Walleij <linus.ml.walleij@gmail.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 311 insertions, 0 deletions

diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index aeecbc932fb..e171e77f612 100644
--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -136,6 +136,18 @@ config MMC_SDHCI_S3C
 
           If unsure, say N.
 
+config MMC_SDHCI_SPEAR
+        tristate "SDHCI support on ST SPEAr platform"
+        depends on MMC_SDHCI && PLAT_SPEAR
+        help
+          This selects the Secure Digital Host Controller Interface (SDHCI)
+          often referrered to as the HSMMC block in some of the ST SPEAR range
+          of SoC
+
+          If you have a controller with this interface, say Y or M here.
+
+          If unsure, say N.
+
 config MMC_SDHCI_S3C_DMA
         bool "DMA support on S3C SDHCI"
         depends on MMC_SDHCI_S3C && EXPERIMENTAL
diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
index 2447b66afeb..e30c2ee4889 100644
--- a/drivers/mmc/host/Makefile
+++ b/drivers/mmc/host/Makefile
@@ -14,6 +14,7 @@ obj-$(CONFIG_MMC_SDHCI)		+= sdhci.o
 obj-$(CONFIG_MMC_SDHCI_PCI)     += sdhci-pci.o
 obj-$(CONFIG_MMC_SDHCI_PLTFM)   += sdhci-pltfm.o
 obj-$(CONFIG_MMC_SDHCI_S3C)     += sdhci-s3c.o
+obj-$(CONFIG_MMC_SDHCI_SPEAR)   += sdhci-spear.o
 obj-$(CONFIG_MMC_WBSD)          += wbsd.o
 obj-$(CONFIG_MMC_AU1X)          += au1xmmc.o
 obj-$(CONFIG_MMC_OMAP)          += omap.o
diff --git a/drivers/mmc/host/sdhci-spear.c b/drivers/mmc/host/sdhci-spear.c
new file mode 100644
index 00000000000..d70c54c7b70
--- /dev/null
+++ b/drivers/mmc/host/sdhci-spear.c
@@ -0,0 +1,298 @@
+/*
+ * drivers/mmc/host/sdhci-spear.c
+ *
+ * Support of SDHCI platform devices for spear soc family
+ *
+ * Copyright (C) 2010 ST Microelectronics
+ * Viresh Kumar<viresh.kumar@st.com>
+ *
+ * Inspired by sdhci-pltfm.c
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/gpio.h>
+#include <linux/highmem.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/mmc/host.h>
+#include <linux/mmc/sdhci-spear.h>
+#include <linux/io.h>
+#include "sdhci.h"
+
+struct spear_sdhci {
+        struct clk *clk;
+        struct sdhci_plat_data *data;
+};
+
+/* sdhci ops */
+static struct sdhci_ops sdhci_pltfm_ops = {
+        /* Nothing to do for now. */
+};
+
+/* gpio card detection interrupt handler */
+static irqreturn_t sdhci_gpio_irq(int irq, void *dev_id)
+{
+        struct platform_device *pdev = dev_id;
+        struct sdhci_host *host = platform_get_drvdata(pdev);
+        struct spear_sdhci *sdhci = dev_get_platdata(&pdev->dev);
+        unsigned long gpio_irq_type;
+        int val;
+
+        val = gpio_get_value(sdhci->data->card_int_gpio);
+
+        /* val == 1 -> card removed, val == 0 -> card inserted */
+        /* if card removed - set irq for low level, else vice versa */
+        gpio_irq_type = val ? IRQF_TRIGGER_LOW : IRQF_TRIGGER_HIGH;
+        set_irq_type(irq, gpio_irq_type);
+
+        if (sdhci->data->card_power_gpio >= 0) {
+                if (!sdhci->data->power_always_enb) {
+                        /* if card inserted, give power, otherwise remove it */
+                        val = sdhci->data->power_active_high ? !val : val ;
+                        gpio_set_value(sdhci->data->card_power_gpio, val);
+                }
+        }
+
+        /* inform sdhci driver about card insertion/removal */
+        tasklet_schedule(&host->card_tasklet);
+
+        return IRQ_HANDLED;
+}
+
+static int __devinit sdhci_probe(struct platform_device *pdev)
+{
+        struct sdhci_host *host;
+        struct resource *iomem;
+        struct spear_sdhci *sdhci;
+        int ret;
+
+        BUG_ON(pdev == NULL);
+
+        iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        if (!iomem) {
+                ret = -ENOMEM;
+                dev_dbg(&pdev->dev, "memory resource not defined\n");
+                goto err;
+        }
+
+        if (!request_mem_region(iomem->start, resource_size(iomem),
+                                "spear-sdhci")) {
+                ret = -EBUSY;
+                dev_dbg(&pdev->dev, "cannot request region\n");
+                goto err;
+        }
+
+        sdhci = kzalloc(sizeof(*sdhci), GFP_KERNEL);
+        if (!sdhci) {
+                ret = -ENOMEM;
+                dev_dbg(&pdev->dev, "cannot allocate memory for sdhci\n");
+                goto err_kzalloc;
+        }
+
+        /* clk enable */
+        sdhci->clk = clk_get(&pdev->dev, NULL);
+        if (IS_ERR(sdhci->clk)) {
+                ret = PTR_ERR(sdhci->clk);
+                dev_dbg(&pdev->dev, "Error getting clock\n");
+                goto err_clk_get;
+        }
+
+        ret = clk_enable(sdhci->clk);
+        if (ret) {
+                dev_dbg(&pdev->dev, "Error enabling clock\n");
+                goto err_clk_enb;
+        }
+
+        /* overwrite platform_data */
+        sdhci->data = dev_get_platdata(&pdev->dev);
+        pdev->dev.platform_data = sdhci;
+
+        if (pdev->dev.parent)
+                host = sdhci_alloc_host(pdev->dev.parent, 0);
+        else
+                host = sdhci_alloc_host(&pdev->dev, 0);
+
+        if (IS_ERR(host)) {
+                ret = PTR_ERR(host);
+                dev_dbg(&pdev->dev, "error allocating host\n");
+                goto err_alloc_host;
+        }
+
+        host->hw_name = "sdhci";
+        host->ops = &sdhci_pltfm_ops;
+        host->irq = platform_get_irq(pdev, 0);
+        host->quirks = SDHCI_QUIRK_BROKEN_ADMA;
+
+        host->ioaddr = ioremap(iomem->start, resource_size(iomem));
+        if (!host->ioaddr) {
+                ret = -ENOMEM;
+                dev_dbg(&pdev->dev, "failed to remap registers\n");
+                goto err_ioremap;
+        }
+
+        ret = sdhci_add_host(host);
+        if (ret) {
+                dev_dbg(&pdev->dev, "error adding host\n");
+                goto err_add_host;
+        }
+
+        platform_set_drvdata(pdev, host);
+
+        /*
+         * It is optional to use GPIOs for sdhci Power control & sdhci card
+         * interrupt detection. If sdhci->data is NULL, then use original sdhci
+         * lines otherwise GPIO lines.
+         * If GPIO is selected for power control, then power should be disabled
+         * after card removal and should be enabled when card insertion
+         * interrupt occurs
+         */
+        if (!sdhci->data)
+                return 0;
+
+        if (sdhci->data->card_power_gpio >= 0) {
+                int val = 0;
+
+                ret = gpio_request(sdhci->data->card_power_gpio, "sdhci");
+                if (ret < 0) {
+                        dev_dbg(&pdev->dev, "gpio request fail: %d\n",
+                                        sdhci->data->card_power_gpio);
+                        goto err_pgpio_request;
+                }
+
+                if (sdhci->data->power_always_enb)
+                        val = sdhci->data->power_active_high;
+                else
+                        val = !sdhci->data->power_active_high;
+
+                ret = gpio_direction_output(sdhci->data->card_power_gpio, val);
+                if (ret) {
+                        dev_dbg(&pdev->dev, "gpio set direction fail: %d\n",
+                                        sdhci->data->card_power_gpio);
+                        goto err_pgpio_direction;
+                }
+
+                gpio_set_value(sdhci->data->card_power_gpio, 1);
+        }
+
+        if (sdhci->data->card_int_gpio >= 0) {
+                ret = gpio_request(sdhci->data->card_int_gpio, "sdhci");
+                if (ret < 0) {
+                        dev_dbg(&pdev->dev, "gpio request fail: %d\n",
+                                        sdhci->data->card_int_gpio);
+                        goto err_igpio_request;
+                }
+
+                ret = gpio_direction_input(sdhci->data->card_int_gpio);
+                if (ret) {
+                        dev_dbg(&pdev->dev, "gpio set direction fail: %d\n",
+                                        sdhci->data->card_int_gpio);
+                        goto err_igpio_direction;
+                }
+                ret = request_irq(gpio_to_irq(sdhci->data->card_int_gpio),
+                                sdhci_gpio_irq, IRQF_TRIGGER_LOW,
+                                mmc_hostname(host->mmc), pdev);
+                if (ret) {
+                        dev_dbg(&pdev->dev, "gpio request irq fail: %d\n",
+                                        sdhci->data->card_int_gpio);
+                        goto err_igpio_request_irq;
+                }
+
+        }
+
+        return 0;
+
+err_igpio_request_irq:
+err_igpio_direction:
+        if (sdhci->data->card_int_gpio >= 0)
+                gpio_free(sdhci->data->card_int_gpio);
+err_igpio_request:
+err_pgpio_direction:
+        if (sdhci->data->card_power_gpio >= 0)
+                gpio_free(sdhci->data->card_power_gpio);
+err_pgpio_request:
+        platform_set_drvdata(pdev, NULL);
+        sdhci_remove_host(host, 1);
+err_add_host:
+        iounmap(host->ioaddr);
+err_ioremap:
+        sdhci_free_host(host);
+err_alloc_host:
+        clk_disable(sdhci->clk);
+err_clk_enb:
+        clk_put(sdhci->clk);
+err_clk_get:
+        kfree(sdhci);
+err_kzalloc:
+        release_mem_region(iomem->start, resource_size(iomem));
+err:
+        dev_err(&pdev->dev, "spear-sdhci probe failed: %d\n", ret);
+        return ret;
+}
+
+static int __devexit sdhci_remove(struct platform_device *pdev)
+{
+        struct sdhci_host *host = platform_get_drvdata(pdev);
+        struct resource *iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        struct spear_sdhci *sdhci = dev_get_platdata(&pdev->dev);
+        int dead;
+        u32 scratch;
+
+        if (sdhci->data) {
+                if (sdhci->data->card_int_gpio >= 0) {
+                        free_irq(gpio_to_irq(sdhci->data->card_int_gpio), pdev);
+                        gpio_free(sdhci->data->card_int_gpio);
+                }
+
+                if (sdhci->data->card_power_gpio >= 0)
+                        gpio_free(sdhci->data->card_power_gpio);
+        }
+
+        platform_set_drvdata(pdev, NULL);
+        dead = 0;
+        scratch = readl(host->ioaddr + SDHCI_INT_STATUS);
+        if (scratch == (u32)-1)
+                dead = 1;
+
+        sdhci_remove_host(host, dead);
+        iounmap(host->ioaddr);
+        sdhci_free_host(host);
+        clk_disable(sdhci->clk);
+        clk_put(sdhci->clk);
+        kfree(sdhci);
+        if (iomem)
+                release_mem_region(iomem->start, resource_size(iomem));
+
+        return 0;
+}
+
+static struct platform_driver sdhci_driver = {
+        .driver = {
+                .name   = "sdhci",
+                .owner  = THIS_MODULE,
+        },
+        .probe          = sdhci_probe,
+        .remove         = __devexit_p(sdhci_remove),
+};
+
+static int __init sdhci_init(void)
+{
+        return platform_driver_register(&sdhci_driver);
+}
+module_init(sdhci_init);
+
+static void __exit sdhci_exit(void)
+{
+        platform_driver_unregister(&sdhci_driver);
+}
+module_exit(sdhci_exit);
+
+MODULE_DESCRIPTION("SPEAr Secure Digital Host Controller Interface driver");
+MODULE_AUTHOR("Viresh Kumar <viresh.kumar@st.com>");
+MODULE_LICENSE("GPL v2");