SDHCI: Samsung SDHCI (HSMMC) driver

Add support for the 'HSMMC' block(s) in the Samsung SoC
line. These are compatible with the SDHCI driver so add
the necessary setup and driver binding for the platform
devices.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>

3 files changed, 307 insertions, 0 deletions

diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index dfa585f7fea..da40c586aca 100644
--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -48,6 +48,18 @@ config MMC_SDHCI_PCI
 
 	  If unsure, say N.
 
+config MMC_SDHCI_S3C
+	tristate "SDHCI support on Samsung S3C SoC"
+	depends on MMC_SDHCI && (PLAT_S3C24XX || PLAT_S3C64XX)
+	help
+	  This selects the Secure Digital Host Controller Interface (SDHCI)
+	  often referrered to as the HSMMC block in some of the Samsung S3C
+	  range of SoC.
+
+	  If you have a controller with this interface, say Y or M here.
+
+	  If unsure, say N.
+
 config MMC_RICOH_MMC
 	tristate "Ricoh MMC Controller Disabler  (EXPERIMENTAL)"
 	depends on MMC_SDHCI_PCI
diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
index c794cc5ce44..779b1ea9a60 100644
--- a/drivers/mmc/host/Makefile
+++ b/drivers/mmc/host/Makefile
@@ -11,6 +11,7 @@ obj-$(CONFIG_MMC_PXA)		+= pxamci.o
 obj-$(CONFIG_MMC_IMX)		+= imxmmc.o
 obj-$(CONFIG_MMC_SDHCI)		+= sdhci.o
 obj-$(CONFIG_MMC_SDHCI_PCI)	+= sdhci-pci.o
+obj-$(CONFIG_MMC_SDHCI_S3C)	+= sdhci-s3c.o
 obj-$(CONFIG_MMC_RICOH_MMC)	+= ricoh_mmc.o
 obj-$(CONFIG_MMC_WBSD)		+= wbsd.o
 obj-$(CONFIG_MMC_AU1X)		+= au1xmmc.o
diff --git a/drivers/mmc/host/sdhci-s3c.c b/drivers/mmc/host/sdhci-s3c.c
new file mode 100644
index 00000000000..554befa1786
--- /dev/null
+++ b/drivers/mmc/host/sdhci-s3c.c
@@ -0,0 +1,294 @@
+/* linux/drivers/mmc/host/sdhci-s3c.c
+ *
+ * Copyright 2008 Openmoko Inc.
+ * Copyright 2008 Simtec Electronics
+ *      Ben Dooks <ben@simtec.co.uk>
+ *      http://armlinux.simtec.co.uk/
+ *
+ * SDHCI (HSMMC) support for Samsung SoC
+ *
+ * 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/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/platform_device.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+
+#include <linux/mmc/host.h>
+
+#include <plat/sdhci.h>
+
+#include "sdhci.h"
+
+#define MAX_BUS_CLK	(4)
+
+struct sdhci_s3c {
+	struct sdhci_host	*host;
+	struct platform_device	*pdev;
+	struct resource		*ioarea;
+	struct s3c_sdhci_platdata *pdata;
+
+	struct clk		*clk_io;	/* clock for io bus */
+	struct clk		*clk_bus[MAX_BUS_CLK];
+};
+
+static inline struct sdhci_s3c *to_s3c(struct sdhci_host *host)
+{
+	return sdhci_priv(host);
+}
+
+
+static void sdhci_s3c_sel_sclk(struct sdhci_host *host)
+{
+	struct sdhci_s3c *ourhost = to_s3c(host);
+
+	/* select sclk */
+	u32 tmp = readl(host->ioaddr + 0x80);
+
+	if ((tmp & (3 << 4)) == (2 << 4))
+		return;
+
+	tmp &= ~(3<<4);
+	tmp |= (2 << 4);
+	writel(tmp, host->ioaddr + 0x80);
+}
+
+
+static unsigned int sdhci_s3c_get_max_clk(struct sdhci_host *host)
+{
+	struct sdhci_s3c *ourhost = to_s3c(host);
+	u32 control2;
+	unsigned int rate;
+	int clk;
+
+	/* note, a reset will reset the clock source */
+
+	sdhci_s3c_sel_sclk(host);
+
+	control2 = readl(host->ioaddr + 0x80);
+	clk = clk_get_rate(ourhost->clk_bus[(control2 >> 4) & 3]);
+
+	return clk;
+}
+
+static unsigned int sdhci_s3c_get_timeout_clk(struct sdhci_host *host)
+{
+	return sdhci_s3c_get_max_clk(host) / 1000000;
+}
+
+static void sdhci_s3c_set_ios(struct sdhci_host *host,
+			      struct mmc_ios *ios)
+{
+	struct sdhci_s3c *ourhost = to_s3c(host);
+	struct s3c_sdhci_platdata *pdata = ourhost->pdata;
+	int width;
+
+	sdhci_s3c_sel_sclk(host);
+
+	if (ios->power_mode != MMC_POWER_OFF) {
+		switch (ios->bus_width) {
+		case MMC_BUS_WIDTH_4:
+			width = 4;
+			break;
+		case MMC_BUS_WIDTH_1:
+			width = 1;
+			break;
+		default:
+			BUG();
+		}
+
+		if (pdata->cfg_gpio)
+			pdata->cfg_gpio(ourhost->pdev, width);
+	}
+
+	if (pdata->cfg_card)
+		pdata->cfg_card(ourhost->pdev, host->ioaddr,
+				ios, host->mmc->card);
+}
+
+static struct sdhci_ops sdhci_s3c_ops = {
+	.get_max_clock		= sdhci_s3c_get_max_clk,
+	.get_timeout_clock	= sdhci_s3c_get_timeout_clk,
+	.set_ios		= sdhci_s3c_set_ios,
+};
+
+static int __devinit sdhci_s3c_probe(struct platform_device *pdev)
+{
+	struct s3c_sdhci_platdata *pdata = pdev->dev.platform_data;
+	struct device *dev = &pdev->dev;
+	struct sdhci_host *host;
+	struct sdhci_s3c *sc;
+	struct resource *res;
+	int ret, irq, ptr, clks;
+
+	if (!pdata) {
+		dev_err(dev, "no device data specified\n");
+		return -ENOENT;
+	}
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		dev_err(dev, "no irq specified\n");
+		return irq;
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_err(dev, "no memory specified\n");
+		return -ENOENT;
+	}
+
+	host = sdhci_alloc_host(dev, sizeof(struct sdhci_s3c));
+	if (IS_ERR(host)) {
+		dev_err(dev, "sdhci_alloc_host() failed\n");
+		return PTR_ERR(host);
+	}
+
+	sc = sdhci_priv(host);
+
+	sc->host = host;
+	sc->pdev = pdev;
+	sc->pdata = pdata;
+
+	sc->clk_io = clk_get(dev, "hsmmc");
+	if (IS_ERR(sc->clk_io)) {
+		dev_err(dev, "failed to get io clock\n");
+		ret = PTR_ERR(sc->clk_io);
+		goto err_io_clk;
+	}
+
+	/* enable the local io clock and keep it running for the moment. */
+	clk_enable(sc->clk_io);
+
+	for (clks = 0, ptr = 0; ptr < MAX_BUS_CLK; ptr++) {
+		struct clk *clk;
+		char *name = pdata->clocks[ptr];
+
+		if (name == NULL)
+			continue;
+
+		clk = clk_get(dev, name);
+		if (IS_ERR(clk)) {
+			dev_err(dev, "failed to get clock %s\n", name);
+			continue;
+		}
+
+		clks++;
+		sc->clk_bus[ptr] = clk;
+		clk_enable(clk);
+
+		dev_info(dev, "clock source %d: %s (%ld Hz)\n",
+			 ptr, name, clk_get_rate(clk));
+	}
+
+	if (clks == 0) {
+		dev_err(dev, "failed to find any bus clocks\n");
+		ret = -ENOENT;
+		goto err_no_busclks;
+	}
+
+	sc->ioarea = request_mem_region(res->start, resource_size(res),
+					mmc_hostname(host->mmc));
+	if (!sc->ioarea) {
+		dev_err(dev, "failed to reserve register area\n");
+		ret = -ENXIO;
+		goto err_req_regs;
+	}
+
+	host->ioaddr = ioremap_nocache(res->start, resource_size(res));
+	if (!host->ioaddr) {
+		dev_err(dev, "failed to map registers\n");
+		ret = -ENXIO;
+		goto err_req_regs;
+	}
+
+	/* Ensure we have minimal gpio selected CMD/CLK/Detect */
+	if (pdata->cfg_gpio)
+		pdata->cfg_gpio(pdev, 0);
+
+	sdhci_s3c_sel_sclk(host);
+
+	host->hw_name = "samsung-hsmmc";
+	host->ops = &sdhci_s3c_ops;
+	host->quirks = 0;
+	host->irq = irq;
+
+	/* Setup quirks for the controller */
+
+	/* Currently with ADMA enabled we are getting some length
+	 * interrupts that are not being dealt with, do disable
+	 * ADMA until this is sorted out. */
+	host->quirks |= SDHCI_QUIRK_BROKEN_ADMA;
+	host->quirks |= SDHCI_QUIRK_32BIT_ADMA_SIZE;
+
+	/* It seems we do not get an DATA transfer complete on non-busy
+	 * transfers, not sure if this is a problem with this specific
+	 * SDHCI block, or a missing configuration that needs to be set. */
+	host->quirks |= SDHCI_QUIRK_NO_TCIRQ_ON_NOT_BUSY;
+
+	host->quirks |= (SDHCI_QUIRK_32BIT_DMA_ADDR |
+			 SDHCI_QUIRK_32BIT_DMA_SIZE);
+
+	ret = sdhci_add_host(host);
+	if (ret) {
+		dev_err(dev, "sdhci_add_host() failed\n");
+		goto err_add_host;
+	}
+
+	return 0;
+
+ err_add_host:
+	release_resource(sc->ioarea);
+	kfree(sc->ioarea);
+
+ err_req_regs:
+	for (ptr = 0; ptr < MAX_BUS_CLK; ptr++) {
+		clk_disable(sc->clk_bus[ptr]);
+		clk_put(sc->clk_bus[ptr]);
+	}
+
+ err_no_busclks:
+	clk_disable(sc->clk_io);
+	clk_put(sc->clk_io);
+
+ err_io_clk:
+	sdhci_free_host(host);
+
+	return ret;
+}
+
+static int __devexit sdhci_s3c_remove(struct platform_device *pdev)
+{
+	return 0;
+}
+
+static struct platform_driver sdhci_s3c_driver = {
+	.probe		= sdhci_s3c_probe,
+	.remove		= __devexit_p(sdhci_s3c_remove),
+	.driver		= {
+		.owner	= THIS_MODULE,
+		.name	= "s3c-sdhci",
+	},
+};
+
+static int __init sdhci_s3c_init(void)
+{
+	return platform_driver_register(&sdhci_s3c_driver);
+}
+
+static void __exit sdhci_s3c_exit(void)
+{
+	platform_driver_unregister(&sdhci_s3c_driver);
+}
+
+module_init(sdhci_s3c_init);
+module_exit(sdhci_s3c_exit);
+
+MODULE_DESCRIPTION("Samsung SDHCI (HSMMC) glue");
+MODULE_AUTHOR("Ben Dooks, <ben@simtec.co.uk>");
+MODULE_LICENSE("GPLv2");
+MODULE_ALIAS("platform:s3c-sdhci");