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path: root/drivers/mmc/host/sdhci-of-arasan.c
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Diffstat (limited to 'drivers/mmc/host/sdhci-of-arasan.c')
-rw-r--r--drivers/mmc/host/sdhci-of-arasan.c224
1 files changed, 224 insertions, 0 deletions
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@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@freescale.com>
+ * Anton Vorontsov <avorontsov@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@xilinx.com>");
+MODULE_LICENSE("GPL");

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