[PATCH 3/3] sdhci-pltfm: Add support for CNS3xxx SoC devices

From: Anton Vorontsov
Date: Fri Jun 25 2010 - 14:06:53 EST


There's nothing special, just SoC-specific ops and quirks.

Signed-off-by: Anton Vorontsov <avorontsov@xxxxxxxxxx>
---
drivers/mmc/host/Kconfig | 9 ++++
drivers/mmc/host/Makefile | 1 +
drivers/mmc/host/sdhci-cns3xxx.c | 97 ++++++++++++++++++++++++++++++++++++++
drivers/mmc/host/sdhci-pltfm.c | 3 +
drivers/mmc/host/sdhci-pltfm.h | 4 ++
5 files changed, 114 insertions(+), 0 deletions(-)
create mode 100644 drivers/mmc/host/sdhci-cns3xxx.c

diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index e171e77..d40e39b 100644
--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -121,6 +121,15 @@ config MMC_SDHCI_PLTFM

If unsure, say N.

+config MMC_SDHCI_CNS3XXX
+ bool "SDHCI support on the Cavium Networks CNS3xxx SoC"
+ depends on ARCH_CNS3XXX
+ depends on MMC_SDHCI_PLTFM
+ help
+ This selects the SDHCI support for CNS3xxx System-on-Chip devices.
+
+ If unsure, say N.
+
config MMC_SDHCI_S3C
tristate "SDHCI support on Samsung S3C SoC"
depends on MMC_SDHCI && (PLAT_S3C24XX || PLAT_S3C64XX)
diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
index 28622d5..070c5f3 100644
--- a/drivers/mmc/host/Makefile
+++ b/drivers/mmc/host/Makefile
@@ -38,6 +38,7 @@ obj-$(CONFIG_MMC_SH_MMCIF) += sh_mmcif.o

obj-$(CONFIG_MMC_SDHCI_PLTFM) += sdhci-platform.o
sdhci-platform-y := sdhci-pltfm.o
+sdhci-platform-$(CONFIG_MMC_SDHCI_CNS3XXX) += sdhci-cns3xxx.o

obj-$(CONFIG_MMC_SDHCI_OF) += sdhci-of.o
sdhci-of-y := sdhci-of-core.o
diff --git a/drivers/mmc/host/sdhci-cns3xxx.c b/drivers/mmc/host/sdhci-cns3xxx.c
new file mode 100644
index 0000000..b7050b3
--- /dev/null
+++ b/drivers/mmc/host/sdhci-cns3xxx.c
@@ -0,0 +1,97 @@
+/*
+ * SDHCI support for CNS3xxx SoC
+ *
+ * Copyright 2008 Cavium Networks
+ * Copyright 2010 MontaVista Software, LLC.
+ *
+ * Authors: Scott Shu
+ * Anton Vorontsov <avorontsov@xxxxxxxxxx>
+ *
+ * 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/device.h>
+#include <linux/mmc/host.h>
+#include <linux/sdhci-pltfm.h>
+#include <mach/cns3xxx.h>
+#include "sdhci.h"
+#include "sdhci-pltfm.h"
+
+static unsigned int sdhci_cns3xxx_get_max_clk(struct sdhci_host *host)
+{
+ return 150000000;
+}
+
+static void sdhci_cns3xxx_set_clock(struct sdhci_host *host, unsigned int clock)
+{
+ struct device *dev = mmc_dev(host->mmc);
+ int div = 1;
+ u16 clk;
+ unsigned long timeout;
+
+ if (clock == host->clock)
+ return;
+
+ sdhci_writew(host, 0, SDHCI_CLOCK_CONTROL);
+
+ if (clock == 0)
+ goto out;
+
+ while (host->max_clk / div > clock) {
+ /*
+ * On CNS3xxx divider grows linearly up to 4, and then
+ * exponentially up to 256.
+ */
+ if (div < 4)
+ div += 1;
+ else if (div < 256)
+ div *= 2;
+ else
+ break;
+ }
+
+ dev_dbg(dev, "desired SD clock: %d, actual: %d\n",
+ clock, host->max_clk / div);
+
+ /* Divide by 3 is special. */
+ if (div != 3)
+ div >>= 1;
+
+ clk = div << SDHCI_DIVIDER_SHIFT;
+ clk |= SDHCI_CLOCK_INT_EN;
+ sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
+
+ timeout = 20;
+ while (!((clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL))
+ & SDHCI_CLOCK_INT_STABLE)) {
+ if (timeout == 0) {
+ dev_warn(dev, "clock is unstable");
+ break;
+ }
+ timeout--;
+ mdelay(1);
+ }
+
+ clk |= SDHCI_CLOCK_CARD_EN;
+ sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
+out:
+ host->clock = clock;
+}
+
+static struct sdhci_ops sdhci_cns3xxx_ops = {
+ .get_max_clock = sdhci_cns3xxx_get_max_clk,
+ .set_clock = sdhci_cns3xxx_set_clock,
+};
+
+struct sdhci_pltfm_data sdhci_cns3xxx_pdata = {
+ .ops = &sdhci_cns3xxx_ops,
+ .quirks = SDHCI_QUIRK_BROKEN_DMA |
+ SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
+ SDHCI_QUIRK_INVERTED_WRITE_PROTECT |
+ SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN |
+ SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
+ SDHCI_QUIRK_NONSTANDARD_CLOCK,
+};
diff --git a/drivers/mmc/host/sdhci-pltfm.c b/drivers/mmc/host/sdhci-pltfm.c
index 4c043bb..e045e3c 100644
--- a/drivers/mmc/host/sdhci-pltfm.c
+++ b/drivers/mmc/host/sdhci-pltfm.c
@@ -158,6 +158,9 @@ static int __devexit sdhci_pltfm_remove(struct platform_device *pdev)

static const struct platform_device_id sdhci_pltfm_ids[] = {
{ "sdhci", },
+#ifdef CONFIG_MMC_SDHCI_CNS3XXX
+ { "sdhci-cns3xxx", (kernel_ulong_t)&sdhci_cns3xxx_pdata },
+#endif
{ },
};
MODULE_DEVICE_TABLE(platform, sdhci_pltfm_ids);
diff --git a/drivers/mmc/host/sdhci-pltfm.h b/drivers/mmc/host/sdhci-pltfm.h
index 4aa07a9..900f329 100644
--- a/drivers/mmc/host/sdhci-pltfm.h
+++ b/drivers/mmc/host/sdhci-pltfm.h
@@ -11,4 +11,8 @@
#ifndef _DRIVERS_MMC_SDHCI_PLTFM_H
#define _DRIVERS_MMC_SDHCI_PLTFM_H

+#include <linux/sdhci-pltfm.h>
+
+extern struct sdhci_pltfm_data sdhci_cns3xxx_pdata;
+
#endif /* _DRIVERS_MMC_SDHCI_PLTFM_H */
--
1.7.0.5
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