Permalink
Fetching contributors…
Cannot retrieve contributors at this time
221 lines (185 sloc) 4.99 KB
/*
* 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/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/slot-gpio.h>
#include <linux/io.h>
#include "sdhci.h"
struct spear_sdhci {
struct clk *clk;
int card_int_gpio;
};
/* 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 void sdhci_probe_config_dt(struct device_node *np,
struct spear_sdhci *host)
{
int cd_gpio;
cd_gpio = of_get_named_gpio(np, "cd-gpios", 0);
if (!gpio_is_valid(cd_gpio))
cd_gpio = -1;
host->card_int_gpio = cd_gpio;
}
static int sdhci_probe(struct platform_device *pdev)
{
struct sdhci_host *host;
struct resource *iomem;
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;
}
iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
host->ioaddr = devm_ioremap_resource(&pdev->dev, iomem);
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));
sdhci_probe_config_dt(pdev->dev.of_node, sdhci);
/*
* It is optional to use GPIOs for sdhci card detection. If
* sdhci->card_int_gpio < 0, then use original sdhci lines otherwise
* GPIO lines. We use the built-in GPIO support for this.
*/
if (sdhci->card_int_gpio >= 0) {
ret = mmc_gpio_request_cd(host->mmc, sdhci->card_int_gpio, 0);
if (ret < 0) {
dev_dbg(&pdev->dev,
"failed to request card-detect gpio%d\n",
sdhci->card_int_gpio);
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",
.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");