diff options
Diffstat (limited to 'drivers/mmc/host/sdhci-of-arasan.c')
| -rw-r--r-- | drivers/mmc/host/sdhci-of-arasan.c | 224 |
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"); |