diff options
Diffstat (limited to 'drivers/mmc/host/sdhci-spear.c')
-rw-r--r-- | drivers/mmc/host/sdhci-spear.c | 298 |
1 files changed, 298 insertions, 0 deletions
diff --git a/drivers/mmc/host/sdhci-spear.c b/drivers/mmc/host/sdhci-spear.c new file mode 100644 index 0000000..d70c54c --- /dev/null +++ b/drivers/mmc/host/sdhci-spear.c @@ -0,0 +1,298 @@ +/* + * drivers/mmc/host/sdhci-spear.c + * + * Support of SDHCI platform devices for spear soc family + * + * Copyright (C) 2010 ST Microelectronics + * Viresh Kumar<viresh.kumar@st.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/interrupt.h> +#include <linux/irq.h> +#include <linux/platform_device.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 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; + 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; +} + +static int __devinit sdhci_probe(struct platform_device *pdev) +{ + struct sdhci_host *host; + struct resource *iomem; + struct spear_sdhci *sdhci; + int ret; + + BUG_ON(pdev == NULL); + + iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!iomem) { + ret = -ENOMEM; + dev_dbg(&pdev->dev, "memory resource not defined\n"); + goto err; + } + + if (!request_mem_region(iomem->start, resource_size(iomem), + "spear-sdhci")) { + ret = -EBUSY; + dev_dbg(&pdev->dev, "cannot request region\n"); + goto err; + } + + sdhci = kzalloc(sizeof(*sdhci), GFP_KERNEL); + if (!sdhci) { + ret = -ENOMEM; + dev_dbg(&pdev->dev, "cannot allocate memory for sdhci\n"); + goto err_kzalloc; + } + + /* 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_clk_get; + } + + ret = clk_enable(sdhci->clk); + if (ret) { + dev_dbg(&pdev->dev, "Error enabling clock\n"); + goto err_clk_enb; + } + + /* overwrite platform_data */ + 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 err_alloc_host; + } + + host->hw_name = "sdhci"; + host->ops = &sdhci_pltfm_ops; + host->irq = platform_get_irq(pdev, 0); + host->quirks = SDHCI_QUIRK_BROKEN_ADMA; + + host->ioaddr = ioremap(iomem->start, resource_size(iomem)); + if (!host->ioaddr) { + ret = -ENOMEM; + dev_dbg(&pdev->dev, "failed to remap registers\n"); + goto err_ioremap; + } + + ret = sdhci_add_host(host); + if (ret) { + dev_dbg(&pdev->dev, "error adding host\n"); + goto err_add_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 = gpio_request(sdhci->data->card_power_gpio, "sdhci"); + if (ret < 0) { + dev_dbg(&pdev->dev, "gpio request fail: %d\n", + sdhci->data->card_power_gpio); + goto err_pgpio_request; + } + + 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 err_pgpio_direction; + } + + gpio_set_value(sdhci->data->card_power_gpio, 1); + } + + if (sdhci->data->card_int_gpio >= 0) { + ret = gpio_request(sdhci->data->card_int_gpio, "sdhci"); + if (ret < 0) { + dev_dbg(&pdev->dev, "gpio request fail: %d\n", + sdhci->data->card_int_gpio); + goto err_igpio_request; + } + + 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 err_igpio_direction; + } + ret = request_irq(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 err_igpio_request_irq; + } + + } + + return 0; + +err_igpio_request_irq: +err_igpio_direction: + if (sdhci->data->card_int_gpio >= 0) + gpio_free(sdhci->data->card_int_gpio); +err_igpio_request: +err_pgpio_direction: + if (sdhci->data->card_power_gpio >= 0) + gpio_free(sdhci->data->card_power_gpio); +err_pgpio_request: + platform_set_drvdata(pdev, NULL); + sdhci_remove_host(host, 1); +err_add_host: + iounmap(host->ioaddr); +err_ioremap: + sdhci_free_host(host); +err_alloc_host: + clk_disable(sdhci->clk); +err_clk_enb: + clk_put(sdhci->clk); +err_clk_get: + kfree(sdhci); +err_kzalloc: + release_mem_region(iomem->start, resource_size(iomem)); +err: + dev_err(&pdev->dev, "spear-sdhci probe failed: %d\n", ret); + return ret; +} + +static int __devexit sdhci_remove(struct platform_device *pdev) +{ + struct sdhci_host *host = platform_get_drvdata(pdev); + struct resource *iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + struct spear_sdhci *sdhci = dev_get_platdata(&pdev->dev); + int dead; + u32 scratch; + + if (sdhci->data) { + if (sdhci->data->card_int_gpio >= 0) { + free_irq(gpio_to_irq(sdhci->data->card_int_gpio), pdev); + gpio_free(sdhci->data->card_int_gpio); + } + + if (sdhci->data->card_power_gpio >= 0) + gpio_free(sdhci->data->card_power_gpio); + } + + platform_set_drvdata(pdev, NULL); + dead = 0; + scratch = readl(host->ioaddr + SDHCI_INT_STATUS); + if (scratch == (u32)-1) + dead = 1; + + sdhci_remove_host(host, dead); + iounmap(host->ioaddr); + sdhci_free_host(host); + clk_disable(sdhci->clk); + clk_put(sdhci->clk); + kfree(sdhci); + if (iomem) + release_mem_region(iomem->start, resource_size(iomem)); + + return 0; +} + +static struct platform_driver sdhci_driver = { + .driver = { + .name = "sdhci", + .owner = THIS_MODULE, + }, + .probe = sdhci_probe, + .remove = __devexit_p(sdhci_remove), +}; + +static int __init sdhci_init(void) +{ + return platform_driver_register(&sdhci_driver); +} +module_init(sdhci_init); + +static void __exit sdhci_exit(void) +{ + platform_driver_unregister(&sdhci_driver); +} +module_exit(sdhci_exit); + +MODULE_DESCRIPTION("SPEAr Secure Digital Host Controller Interface driver"); +MODULE_AUTHOR("Viresh Kumar <viresh.kumar@st.com>"); +MODULE_LICENSE("GPL v2"); |