diff options
Diffstat (limited to 'drivers/mmc/host/sdhci-spear.c')
| -rw-r--r-- | drivers/mmc/host/sdhci-spear.c | 349 |
1 files changed, 349 insertions, 0 deletions
diff --git a/drivers/mmc/host/sdhci-spear.c b/drivers/mmc/host/sdhci-spear.c new file mode 100644 index 00000000..7ae5b3ae --- /dev/null +++ b/drivers/mmc/host/sdhci-spear.c @@ -0,0 +1,349 @@ +/* + * drivers/mmc/host/sdhci-spear.c + * + * Support of SDHCI platform devices for spear soc family + * + * Copyright (C) 2010 ST Microelectronics + * Viresh Kumar <viresh.linux@gmail.com> + * + * 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/gpio.h> +#include <linux/highmem.h> +#include <linux/module.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/of.h> +#include <linux/of_gpio.h> +#include <linux/platform_device.h> +#include <linux/pm.h> +#include <linux/slab.h> +#include <linux/mmc/host.h> +#include <linux/mmc/sdhci-spear.h> +#include <linux/io.h> +#include "sdhci.h" + +struct spear_sdhci { + struct clk *clk; + struct sdhci_plat_data *data; +}; + +/* sdhci ops */ +static const struct sdhci_ops sdhci_pltfm_ops = { + /* Nothing to do for now. */ +}; + +/* gpio card detection interrupt handler */ +static irqreturn_t sdhci_gpio_irq(int irq, void *dev_id) +{ + struct platform_device *pdev = dev_id; + struct sdhci_host *host = platform_get_drvdata(pdev); + struct spear_sdhci *sdhci = dev_get_platdata(&pdev->dev); + unsigned long gpio_irq_type; + int val; + + val = gpio_get_value(sdhci->data->card_int_gpio); + + /* val == 1 -> card removed, val == 0 -> card inserted */ + /* if card removed - set irq for low level, else vice versa */ + gpio_irq_type = val ? IRQF_TRIGGER_LOW : IRQF_TRIGGER_HIGH; + irq_set_irq_type(irq, gpio_irq_type); + + if (sdhci->data->card_power_gpio >= 0) { + if (!sdhci->data->power_always_enb) { + /* if card inserted, give power, otherwise remove it */ + val = sdhci->data->power_active_high ? !val : val ; + gpio_set_value(sdhci->data->card_power_gpio, val); + } + } + + /* inform sdhci driver about card insertion/removal */ + tasklet_schedule(&host->card_tasklet); + + return IRQ_HANDLED; +} + +#ifdef CONFIG_OF +static struct sdhci_plat_data *sdhci_probe_config_dt(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct sdhci_plat_data *pdata = NULL; + int cd_gpio; + + cd_gpio = of_get_named_gpio(np, "cd-gpios", 0); + if (!gpio_is_valid(cd_gpio)) + cd_gpio = -1; + + /* If pdata is required */ + if (cd_gpio != -1) { + pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); + if (!pdata) { + dev_err(&pdev->dev, "DT: kzalloc failed\n"); + return ERR_PTR(-ENOMEM); + } + } + + pdata->card_int_gpio = cd_gpio; + + return pdata; +} +#else +static struct sdhci_plat_data *sdhci_probe_config_dt(struct platform_device *pdev) +{ + return ERR_PTR(-ENOSYS); +} +#endif + +static int sdhci_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct sdhci_host *host; + struct resource *iomem; + struct spear_sdhci *sdhci; + int ret; + + iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!iomem) { + ret = -ENOMEM; + dev_dbg(&pdev->dev, "memory resource not defined\n"); + goto err; + } + + if (!devm_request_mem_region(&pdev->dev, iomem->start, + resource_size(iomem), "spear-sdhci")) { + ret = -EBUSY; + dev_dbg(&pdev->dev, "cannot request region\n"); + goto err; + } + + sdhci = devm_kzalloc(&pdev->dev, sizeof(*sdhci), GFP_KERNEL); + if (!sdhci) { + ret = -ENOMEM; + dev_dbg(&pdev->dev, "cannot allocate memory for sdhci\n"); + goto err; + } + + /* clk enable */ + sdhci->clk = 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; + } + + ret = clk_prepare_enable(sdhci->clk); + if (ret) { + dev_dbg(&pdev->dev, "Error enabling clock\n"); + goto put_clk; + } + + 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)); + + if (np) { + sdhci->data = sdhci_probe_config_dt(pdev); + if (IS_ERR(sdhci->data)) { + dev_err(&pdev->dev, "DT: Failed to get pdata\n"); + return -ENODEV; + } + } else { + sdhci->data = dev_get_platdata(&pdev->dev); + } + + pdev->dev.platform_data = sdhci; + + if (pdev->dev.parent) + host = sdhci_alloc_host(pdev->dev.parent, 0); + else + host = sdhci_alloc_host(&pdev->dev, 0); + + if (IS_ERR(host)) { + ret = PTR_ERR(host); + dev_dbg(&pdev->dev, "error allocating host\n"); + goto disable_clk; + } + + host->hw_name = "sdhci"; + host->ops = &sdhci_pltfm_ops; + host->irq = platform_get_irq(pdev, 0); + host->quirks = SDHCI_QUIRK_BROKEN_ADMA; + + host->ioaddr = devm_ioremap(&pdev->dev, iomem->start, + resource_size(iomem)); + if (!host->ioaddr) { + ret = -ENOMEM; + dev_dbg(&pdev->dev, "failed to remap registers\n"); + goto free_host; + } + + ret = sdhci_add_host(host); + if (ret) { + dev_dbg(&pdev->dev, "error adding host\n"); + goto free_host; + } + + platform_set_drvdata(pdev, host); + + /* + * It is optional to use GPIOs for sdhci Power control & sdhci card + * interrupt detection. If sdhci->data is NULL, then use original sdhci + * lines otherwise GPIO lines. + * If GPIO is selected for power control, then power should be disabled + * after card removal and should be enabled when card insertion + * interrupt occurs + */ + if (!sdhci->data) + return 0; + + if (sdhci->data->card_power_gpio >= 0) { + int val = 0; + + ret = devm_gpio_request(&pdev->dev, + sdhci->data->card_power_gpio, "sdhci"); + if (ret < 0) { + dev_dbg(&pdev->dev, "gpio request fail: %d\n", + sdhci->data->card_power_gpio); + goto set_drvdata; + } + + if (sdhci->data->power_always_enb) + val = sdhci->data->power_active_high; + else + val = !sdhci->data->power_active_high; + + ret = gpio_direction_output(sdhci->data->card_power_gpio, val); + if (ret) { + dev_dbg(&pdev->dev, "gpio set direction fail: %d\n", + sdhci->data->card_power_gpio); + goto set_drvdata; + } + } + + if (sdhci->data->card_int_gpio >= 0) { + ret = devm_gpio_request(&pdev->dev, sdhci->data->card_int_gpio, + "sdhci"); + if (ret < 0) { + dev_dbg(&pdev->dev, "gpio request fail: %d\n", + sdhci->data->card_int_gpio); + goto set_drvdata; + } + + ret = gpio_direction_input(sdhci->data->card_int_gpio); + if (ret) { + dev_dbg(&pdev->dev, "gpio set direction fail: %d\n", + sdhci->data->card_int_gpio); + goto set_drvdata; + } + ret = devm_request_irq(&pdev->dev, + gpio_to_irq(sdhci->data->card_int_gpio), + sdhci_gpio_irq, IRQF_TRIGGER_LOW, + mmc_hostname(host->mmc), pdev); + if (ret) { + dev_dbg(&pdev->dev, "gpio request irq fail: %d\n", + sdhci->data->card_int_gpio); + goto set_drvdata; + } + + } + + return 0; + +set_drvdata: + platform_set_drvdata(pdev, NULL); + sdhci_remove_host(host, 1); +free_host: + sdhci_free_host(host); +disable_clk: + clk_disable_unprepare(sdhci->clk); +put_clk: + clk_put(sdhci->clk); +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 = dev_get_platdata(&pdev->dev); + int dead = 0; + u32 scratch; + + platform_set_drvdata(pdev, NULL); + scratch = readl(host->ioaddr + SDHCI_INT_STATUS); + if (scratch == (u32)-1) + dead = 1; + + sdhci_remove_host(host, dead); + sdhci_free_host(host); + clk_disable_unprepare(sdhci->clk); + clk_put(sdhci->clk); + + 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 = dev_get_platdata(dev); + int ret; + + 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 = dev_get_platdata(dev); + 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", + .owner = THIS_MODULE, + .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 <viresh.linux@gmail.com>"); +MODULE_LICENSE("GPL v2"); |
