[PATCH v3 1/2] mmc: arasan: Add driver for Arasan SDHCI
Soren Brinkmann
soren.brinkmann at xilinx.com
Mon Dec 2 13:02:36 EST 2013
Add a driver for Arasan's SDHCI controller core.
Signed-off-by: Soren Brinkmann <soren.brinkmann at xilinx.com>
Acked-by: Rob Herring <rob.herring at calxeda.com> [binding]
---
As discussed, I left binding and license header as is and fixed the typos.
v3:
- fix typo in binding documentation
- add missing '>' in MODULE_AUTHOR string
v2:
- document 'interrupts' and 'interrupt-parent' properties in the driver
bindings
- append '-8.9a' IP version specifier to comaptibility string
Thanks,
Sören
.../devicetree/bindings/mmc/arasan,sdhci.txt | 27 +++
MAINTAINERS | 1 +
drivers/mmc/host/Kconfig | 12 ++
drivers/mmc/host/Makefile | 1 +
drivers/mmc/host/sdhci-of-arasan.c | 224 +++++++++++++++++++++
5 files changed, 265 insertions(+)
create mode 100644 Documentation/devicetree/bindings/mmc/arasan,sdhci.txt
create mode 100644 drivers/mmc/host/sdhci-of-arasan.c
diff --git a/Documentation/devicetree/bindings/mmc/arasan,sdhci.txt b/Documentation/devicetree/bindings/mmc/arasan,sdhci.txt
new file mode 100644
index 000000000000..98ee2abbe138
--- /dev/null
+++ b/Documentation/devicetree/bindings/mmc/arasan,sdhci.txt
@@ -0,0 +1,27 @@
+Device Tree Bindings for the Arasan SDHCI Controller
+
+ The bindings follow the mmc[1], clock[2] and interrupt[3] bindings. Only
+ deviations are documented here.
+
+ [1] Documentation/devicetree/bindings/mmc/mmc.txt
+ [2] Documentation/devicetree/bindings/clock/clock-bindings.txt
+ [3] Documentation/devicetree/bindings/interrupt-controller/interrupts.txt
+
+Required Properties:
+ - compatible: Compatibility string. Must be 'arasan,sdhci-8.9a'
+ - reg: From mmc bindings: Register location and length.
+ - clocks: From clock bindings: Handles to clock inputs.
+ - clock-names: From clock bindings: Tuple including "clk_xin" and "clk_ahb"
+ - interrupts: Interrupt specifier
+ - interrupt-parent: Phandle for the interrupt controller that services
+ interrupts for this device.
+
+Example:
+ sdhci at e0100000 {
+ compatible = "arasan,sdhci-8.9a";
+ reg = <0xe0100000 0x1000>;
+ clock-names = "clk_xin", "clk_ahb";
+ clocks = <&clkc 21>, <&clkc 32>;
+ interrupt-parent = <&gic>;
+ interrupts = <0 24 4>;
+ } ;
diff --git a/MAINTAINERS b/MAINTAINERS
index f216db847022..9c98792335d9 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1371,6 +1371,7 @@ T: git git://git.xilinx.com/linux-xlnx.git
S: Supported
F: arch/arm/mach-zynq/
F: drivers/cpuidle/cpuidle-zynq.c
+F: drivers/mmc/host/sdhci-of-arasan.c
ARM SMMU DRIVER
M: Will Deacon <will.deacon at arm.com>
diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index 7fc5099e44b2..1eb090c187bb 100644
--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -104,6 +104,18 @@ config MMC_SDHCI_PLTFM
If unsure, say N.
+config MMC_SDHCI_OF_ARASAN
+ tristate "SDHCI OF support for the Arasan SDHCI controllers"
+ depends on MMC_SDHCI_PLTFM
+ depends on OF
+ help
+ This selects the Arasan Secure Digital Host Controller Interface
+ (SDHCI). This hardware is found e.g. in Xilinx' Zynq SoC.
+
+ If you have a controller with this interface, say Y or M here.
+
+ If unsure, say N.
+
config MMC_SDHCI_OF_ESDHC
tristate "SDHCI OF support for the Freescale eSDHC controller"
depends on MMC_SDHCI_PLTFM
diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
index c41d0c364509..f93617ec6548 100644
--- a/drivers/mmc/host/Makefile
+++ b/drivers/mmc/host/Makefile
@@ -57,6 +57,7 @@ obj-$(CONFIG_MMC_SDHCI_CNS3XXX) += sdhci-cns3xxx.o
obj-$(CONFIG_MMC_SDHCI_ESDHC_IMX) += sdhci-esdhc-imx.o
obj-$(CONFIG_MMC_SDHCI_DOVE) += sdhci-dove.o
obj-$(CONFIG_MMC_SDHCI_TEGRA) += sdhci-tegra.o
+obj-$(CONFIG_MMC_SDHCI_OF_ARASAN) += sdhci-of-arasan.o
obj-$(CONFIG_MMC_SDHCI_OF_ESDHC) += sdhci-of-esdhc.o
obj-$(CONFIG_MMC_SDHCI_OF_HLWD) += sdhci-of-hlwd.o
obj-$(CONFIG_MMC_SDHCI_BCM_KONA) += sdhci-bcm-kona.o
diff --git a/drivers/mmc/host/sdhci-of-arasan.c b/drivers/mmc/host/sdhci-of-arasan.c
new file mode 100644
index 000000000000..f7c7cf62437d
--- /dev/null
+++ b/drivers/mmc/host/sdhci-of-arasan.c
@@ -0,0 +1,224 @@
+/*
+ * Arasan Secure Digital Host Controller Interface.
+ * Copyright (C) 2011 - 2012 Michal Simek <monstr at monstr.eu>
+ * Copyright (c) 2012 Wind River Systems, Inc.
+ * Copyright (C) 2013 Pengutronix e.K.
+ * Copyright (C) 2013 Xilinx Inc.
+ *
+ * Based on sdhci-of-esdhc.c
+ *
+ * Copyright (c) 2007 Freescale Semiconductor, Inc.
+ * Copyright (c) 2009 MontaVista Software, Inc.
+ *
+ * Authors: Xiaobo Xie <X.Xie at freescale.com>
+ * Anton Vorontsov <avorontsov at ru.mvista.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or (at
+ * your option) any later version.
+ */
+
+#include <linux/module.h>
+#include "sdhci-pltfm.h"
+
+#define SDHCI_ARASAN_CLK_CTRL_OFFSET 0x2c
+
+#define CLK_CTRL_TIMEOUT_SHIFT 16
+#define CLK_CTRL_TIMEOUT_MASK (0xf << CLK_CTRL_TIMEOUT_SHIFT)
+#define CLK_CTRL_TIMEOUT_MIN_EXP 13
+
+/**
+ * struct sdhci_arasan_data
+ * @clk_ahb: Pointer to the AHB clock
+ */
+struct sdhci_arasan_data {
+ struct clk *clk_ahb;
+};
+
+static unsigned int sdhci_arasan_get_timeout_clock(struct sdhci_host *host)
+{
+ u32 div;
+ unsigned long freq;
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+
+ div = readl(host->ioaddr + SDHCI_ARASAN_CLK_CTRL_OFFSET);
+ div = (div & CLK_CTRL_TIMEOUT_MASK) >> CLK_CTRL_TIMEOUT_SHIFT;
+
+ freq = clk_get_rate(pltfm_host->clk);
+ freq /= 1 << (CLK_CTRL_TIMEOUT_MIN_EXP + div);
+
+ return freq;
+}
+
+static struct sdhci_ops sdhci_arasan_ops = {
+ .get_max_clock = sdhci_pltfm_clk_get_max_clock,
+ .get_timeout_clock = sdhci_arasan_get_timeout_clock,
+};
+
+static struct sdhci_pltfm_data sdhci_arasan_pdata = {
+ .ops = &sdhci_arasan_ops,
+};
+
+#ifdef CONFIG_PM_SLEEP
+/**
+ * sdhci_arasan_suspend - Suspend method for the driver
+ * @dev: Address of the device structure
+ * Returns 0 on success and error value on error
+ *
+ * Put the device in a low power state.
+ */
+static int sdhci_arasan_suspend(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct sdhci_host *host = platform_get_drvdata(pdev);
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+ struct sdhci_arasan_data *sdhci_arasan = pltfm_host->priv;
+ int ret;
+
+ ret = sdhci_suspend_host(host);
+ if (ret)
+ return ret;
+
+ clk_disable(pltfm_host->clk);
+ clk_disable(sdhci_arasan->clk_ahb);
+
+ return 0;
+}
+
+/**
+ * sdhci_arasan_resume - Resume method for the driver
+ * @dev: Address of the device structure
+ * Returns 0 on success and error value on error
+ *
+ * Resume operation after suspend
+ */
+static int sdhci_arasan_resume(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct sdhci_host *host = platform_get_drvdata(pdev);
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+ struct sdhci_arasan_data *sdhci_arasan = pltfm_host->priv;
+ int ret;
+
+ ret = clk_enable(sdhci_arasan->clk_ahb);
+ if (ret) {
+ dev_err(dev, "Cannot enable AHB clock.\n");
+ return ret;
+ }
+
+ ret = clk_enable(pltfm_host->clk);
+ if (ret) {
+ dev_err(dev, "Cannot enable SD clock.\n");
+ clk_disable(sdhci_arasan->clk_ahb);
+ return ret;
+ }
+
+ return sdhci_resume_host(host);
+}
+#endif /* ! CONFIG_PM_SLEEP */
+
+static SIMPLE_DEV_PM_OPS(sdhci_arasan_dev_pm_ops, sdhci_arasan_suspend,
+ sdhci_arasan_resume);
+
+static int sdhci_arasan_probe(struct platform_device *pdev)
+{
+ int ret;
+ struct clk *clk_xin;
+ struct sdhci_host *host;
+ struct sdhci_pltfm_host *pltfm_host;
+ struct sdhci_arasan_data *sdhci_arasan;
+
+ sdhci_arasan = devm_kzalloc(&pdev->dev, sizeof(*sdhci_arasan),
+ GFP_KERNEL);
+ if (!sdhci_arasan)
+ return -ENOMEM;
+
+ sdhci_arasan->clk_ahb = devm_clk_get(&pdev->dev, "clk_ahb");
+ if (IS_ERR(sdhci_arasan->clk_ahb)) {
+ dev_err(&pdev->dev, "clk_ahb clock not found.\n");
+ return PTR_ERR(sdhci_arasan->clk_ahb);
+ }
+
+ clk_xin = devm_clk_get(&pdev->dev, "clk_xin");
+ if (IS_ERR(clk_xin)) {
+ dev_err(&pdev->dev, "clk_xin clock not found.\n");
+ return PTR_ERR(clk_xin);
+ }
+
+ ret = clk_prepare_enable(sdhci_arasan->clk_ahb);
+ if (ret) {
+ dev_err(&pdev->dev, "Unable to enable AHB clock.\n");
+ return ret;
+ }
+
+ ret = clk_prepare_enable(clk_xin);
+ if (ret) {
+ dev_err(&pdev->dev, "Unable to enable SD clock.\n");
+ goto clk_dis_ahb;
+ }
+
+ host = sdhci_pltfm_init(pdev, &sdhci_arasan_pdata, 0);
+ if (IS_ERR(host)) {
+ ret = PTR_ERR(host);
+ dev_err(&pdev->dev, "platform init failed (%u)\n", ret);
+ goto clk_disable_all;
+ }
+
+ sdhci_get_of_property(pdev);
+ pltfm_host = sdhci_priv(host);
+ pltfm_host->priv = sdhci_arasan;
+ pltfm_host->clk = clk_xin;
+
+ ret = sdhci_add_host(host);
+ if (ret) {
+ dev_err(&pdev->dev, "platform register failed (%u)\n", ret);
+ goto err_pltfm_free;
+ }
+
+ return 0;
+
+err_pltfm_free:
+ sdhci_pltfm_free(pdev);
+clk_disable_all:
+ clk_disable_unprepare(clk_xin);
+clk_dis_ahb:
+ clk_disable_unprepare(sdhci_arasan->clk_ahb);
+
+ return ret;
+}
+
+static int sdhci_arasan_remove(struct platform_device *pdev)
+{
+ struct sdhci_host *host = platform_get_drvdata(pdev);
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+ struct sdhci_arasan_data *sdhci_arasan = pltfm_host->priv;
+
+ clk_disable_unprepare(pltfm_host->clk);
+ clk_disable_unprepare(sdhci_arasan->clk_ahb);
+
+ return sdhci_pltfm_unregister(pdev);
+}
+
+static const struct of_device_id sdhci_arasan_of_match[] = {
+ { .compatible = "arasan,sdhci-8.9a" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, sdhci_arasan_of_match);
+
+static struct platform_driver sdhci_arasan_driver = {
+ .driver = {
+ .name = "sdhci-arasan",
+ .owner = THIS_MODULE,
+ .of_match_table = sdhci_arasan_of_match,
+ .pm = &sdhci_arasan_dev_pm_ops,
+ },
+ .probe = sdhci_arasan_probe,
+ .remove = sdhci_arasan_remove,
+};
+
+module_platform_driver(sdhci_arasan_driver);
+
+MODULE_DESCRIPTION("Driver for the Arasan SDHCI Controller");
+MODULE_AUTHOR("Soeren Brinkmann <soren.brinkmann at xilinx.com>");
+MODULE_LICENSE("GPL");
--
1.8.4.4
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