sdhci-of-arasan.rar_arasan

/* * 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 = { .set_clock = sdhci_set_clock, .get_max_clock = sdhci_pltfm_clk_get_max_clock, .get_timeout_clock = sdhci_arasan_get_timeout_clock, .set_bus_width = sdhci_set_bus_width, .reset = sdhci_reset, .set_uhs_signaling = sdhci_set_uhs_signaling, }; 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); 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) 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", .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");