diff options
Diffstat (limited to 'drivers/mmc/host/sdhci-spear.c')
| -rw-r--r-- | drivers/mmc/host/sdhci-spear.c | 196 |
1 files changed, 196 insertions, 0 deletions
diff --git a/drivers/mmc/host/sdhci-spear.c b/drivers/mmc/host/sdhci-spear.c new file mode 100644 index 000000000..d463e2fd5 --- /dev/null +++ b/drivers/mmc/host/sdhci-spear.c @@ -0,0 +1,196 @@ +/* + * drivers/mmc/host/sdhci-spear.c + * + * Support of SDHCI platform devices for spear soc family + * + * Copyright (C) 2010 ST Microelectronics + * Viresh Kumar <vireshk@kernel.org> + * + * Inspired by sdhci-pltfm.c + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/highmem.h> +#include <linux/module.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/pm.h> +#include <linux/slab.h> +#include <linux/mmc/host.h> +#include <linux/mmc/slot-gpio.h> +#include <linux/io.h> +#include "sdhci.h" + +struct spear_sdhci { + struct clk *clk; +}; + +/* sdhci ops */ +static const struct sdhci_ops sdhci_pltfm_ops = { + .set_clock = sdhci_set_clock, + .set_bus_width = sdhci_set_bus_width, + .reset = sdhci_reset, + .set_uhs_signaling = sdhci_set_uhs_signaling, +}; + +static int sdhci_probe(struct platform_device *pdev) +{ + struct sdhci_host *host; + struct spear_sdhci *sdhci; + struct device *dev; + int ret; + + dev = pdev->dev.parent ? pdev->dev.parent : &pdev->dev; + host = sdhci_alloc_host(dev, sizeof(*sdhci)); + if (IS_ERR(host)) { + ret = PTR_ERR(host); + dev_dbg(&pdev->dev, "cannot allocate memory for sdhci\n"); + goto err; + } + + host->ioaddr = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(host->ioaddr)) { + ret = PTR_ERR(host->ioaddr); + dev_dbg(&pdev->dev, "unable to map iomem: %d\n", ret); + goto err_host; + } + + host->hw_name = "sdhci"; + host->ops = &sdhci_pltfm_ops; + host->irq = platform_get_irq(pdev, 0); + if (host->irq <= 0) { + ret = -EINVAL; + goto err_host; + } + host->quirks = SDHCI_QUIRK_BROKEN_ADMA; + + sdhci = sdhci_priv(host); + + /* clk enable */ + sdhci->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(sdhci->clk)) { + ret = PTR_ERR(sdhci->clk); + dev_dbg(&pdev->dev, "Error getting clock\n"); + goto err_host; + } + + ret = clk_prepare_enable(sdhci->clk); + if (ret) { + dev_dbg(&pdev->dev, "Error enabling clock\n"); + goto err_host; + } + + ret = clk_set_rate(sdhci->clk, 50000000); + if (ret) + dev_dbg(&pdev->dev, "Error setting desired clk, clk=%lu\n", + clk_get_rate(sdhci->clk)); + + /* + * It is optional to use GPIOs for sdhci card detection. If we + * find a descriptor using slot GPIO, we use it. + */ + ret = mmc_gpiod_request_cd(host->mmc, "cd", 0, false, 0); + if (ret == -EPROBE_DEFER) + goto disable_clk; + + ret = sdhci_add_host(host); + if (ret) + goto disable_clk; + + platform_set_drvdata(pdev, host); + + return 0; + +disable_clk: + clk_disable_unprepare(sdhci->clk); +err_host: + sdhci_free_host(host); +err: + dev_err(&pdev->dev, "spear-sdhci probe failed: %d\n", ret); + return ret; +} + +static int sdhci_remove(struct platform_device *pdev) +{ + struct sdhci_host *host = platform_get_drvdata(pdev); + struct spear_sdhci *sdhci = sdhci_priv(host); + int dead = 0; + u32 scratch; + + scratch = readl(host->ioaddr + SDHCI_INT_STATUS); + if (scratch == (u32)-1) + dead = 1; + + sdhci_remove_host(host, dead); + clk_disable_unprepare(sdhci->clk); + sdhci_free_host(host); + + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int sdhci_suspend(struct device *dev) +{ + struct sdhci_host *host = dev_get_drvdata(dev); + struct spear_sdhci *sdhci = sdhci_priv(host); + int ret; + + if (host->tuning_mode != SDHCI_TUNING_MODE_3) + mmc_retune_needed(host->mmc); + + ret = sdhci_suspend_host(host); + if (!ret) + clk_disable(sdhci->clk); + + return ret; +} + +static int sdhci_resume(struct device *dev) +{ + struct sdhci_host *host = dev_get_drvdata(dev); + struct spear_sdhci *sdhci = sdhci_priv(host); + int ret; + + ret = clk_enable(sdhci->clk); + if (ret) { + dev_dbg(dev, "Resume: Error enabling clock\n"); + return ret; + } + + return sdhci_resume_host(host); +} +#endif + +static SIMPLE_DEV_PM_OPS(sdhci_pm_ops, sdhci_suspend, sdhci_resume); + +#ifdef CONFIG_OF +static const struct of_device_id sdhci_spear_id_table[] = { + { .compatible = "st,spear300-sdhci" }, + {} +}; +MODULE_DEVICE_TABLE(of, sdhci_spear_id_table); +#endif + +static struct platform_driver sdhci_driver = { + .driver = { + .name = "sdhci", + .probe_type = PROBE_PREFER_ASYNCHRONOUS, + .pm = &sdhci_pm_ops, + .of_match_table = of_match_ptr(sdhci_spear_id_table), + }, + .probe = sdhci_probe, + .remove = sdhci_remove, +}; + +module_platform_driver(sdhci_driver); + +MODULE_DESCRIPTION("SPEAr Secure Digital Host Controller Interface driver"); +MODULE_AUTHOR("Viresh Kumar <vireshk@kernel.org>"); +MODULE_LICENSE("GPL v2"); |