sdhci-tegra.c
/*
* Copyright (C) 2010 Google, Inc.
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
*/
#include <linux/err.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/gpio.h>
#include <linux/mmc/card.h>
#include <linux/mmc/host.h>
#include <mach/gpio.h>
#include <mach/sdhci.h>
#include "sdhci-pltfm.h"
static u32 tegra_sdhci_readl(struct sdhci_host *host, int reg)
{
u32 val;
if (unlikely(reg == SDHCI_PRESENT_STATE)) {
/* Use wp_gpio here instead? */
val = readl(host->ioaddr + reg);
return val | SDHCI_WRITE_PROTECT;
}
return readl(host->ioaddr + reg);
}
static u16 tegra_sdhci_readw(struct sdhci_host *host, int reg)
{
if (unlikely(reg == SDHCI_HOST_VERSION)) {
/* Erratum: Version register is invalid in HW. */
return SDHCI_SPEC_200;
}
return readw(host->ioaddr + reg);
}
static void tegra_sdhci_writel(struct sdhci_host *host, u32 val, int reg)
{
/* Seems like we're getting spurious timeout and crc errors, so
* disable signalling of them. In case of real errors software
* timers should take care of eventually detecting them.
*/
if (unlikely(reg == SDHCI_SIGNAL_ENABLE))
val &= ~(SDHCI_INT_TIMEOUT|SDHCI_INT_CRC);
writel(val, host->ioaddr + reg);
if (unlikely(reg == SDHCI_INT_ENABLE)) {
/* Erratum: Must enable block gap interrupt detection */
u8 gap_ctrl = readb(host->ioaddr + SDHCI_BLOCK_GAP_CONTROL);
if (val & SDHCI_INT_CARD_INT)
gap_ctrl |= 0x8;
else
gap_ctrl &= ~0x8;
writeb(gap_ctrl, host->ioaddr + SDHCI_BLOCK_GAP_CONTROL);
}
}
static unsigned int tegra_sdhci_get_ro(struct sdhci_host *sdhci)
{
struct platform_device *pdev = to_platform_device(mmc_dev(sdhci->mmc));
struct tegra_sdhci_platform_data *plat;
plat = pdev->dev.platform_data;
if (!gpio_is_valid(plat->wp_gpio))
return -1;
return gpio_get_value(plat->wp_gpio);
}
static irqreturn_t carddetect_irq(int irq, void *data)
{
struct sdhci_host *sdhost = (struct sdhci_host *)data;
tasklet_schedule(&sdhost->card_tasklet);
return IRQ_HANDLED;
};
static int tegra_sdhci_8bit(struct sdhci_host *host, int bus_width)
{
struct platform_device *pdev = to_platform_device(mmc_dev(host->mmc));
struct tegra_sdhci_platform_data *plat;
u32 ctrl;
plat = pdev->dev.platform_data;
ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL);
if (plat->is_8bit && bus_width == MMC_BUS_WIDTH_8) {
ctrl &= ~SDHCI_CTRL_4BITBUS;
ctrl |= SDHCI_CTRL_8BITBUS;
} else {
ctrl &= ~SDHCI_CTRL_8BITBUS;
if (bus_width == MMC_BUS_WIDTH_4)
ctrl |= SDHCI_CTRL_4BITBUS;
else
ctrl &= ~SDHCI_CTRL_4BITBUS;
}
sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
return 0;
}
static struct sdhci_ops tegra_sdhci_ops = {
.get_ro = tegra_sdhci_get_ro,
.read_l = tegra_sdhci_readl,
.read_w = tegra_sdhci_readw,
.write_l = tegra_sdhci_writel,
.platform_8bit_width = tegra_sdhci_8bit,
};
static struct sdhci_pltfm_data sdhci_tegra_pdata = {
.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
SDHCI_QUIRK_SINGLE_POWER_WRITE |
SDHCI_QUIRK_NO_HISPD_BIT |
SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC,
.ops = &tegra_sdhci_ops,
};
static int __devinit sdhci_tegra_probe(struct platform_device *pdev)
{
struct sdhci_pltfm_host *pltfm_host;
struct tegra_sdhci_platform_data *plat;
struct sdhci_host *host;
struct clk *clk;
int rc;
host = sdhci_pltfm_init(pdev, &sdhci_tegra_pdata);
if (IS_ERR(host))
return PTR_ERR(host);
pltfm_host = sdhci_priv(host);
plat = pdev->dev.platform_data;
if (plat == NULL) {
dev_err(mmc_dev(host->mmc), "missing platform data\n");
rc = -ENXIO;
goto err_no_plat;
}
if (gpio_is_valid(plat->power_gpio)) {
rc = gpio_request(plat->power_gpio, "sdhci_power");
if (rc) {
dev_err(mmc_dev(host->mmc),
"failed to allocate power gpio\n");
goto err_power_req;
}
tegra_gpio_enable(plat->power_gpio);
gpio_direction_output(plat->power_gpio, 1);
}
if (gpio_is_valid(plat->cd_gpio)) {
rc = gpio_request(plat->cd_gpio, "sdhci_cd");
if (rc) {
dev_err(mmc_dev(host->mmc),
"failed to allocate cd gpio\n");
goto err_cd_req;
}
tegra_gpio_enable(plat->cd_gpio);
gpio_direction_input(plat->cd_gpio);
rc = request_irq(gpio_to_irq(plat->cd_gpio), carddetect_irq,
IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
mmc_hostname(host->mmc), host);
if (rc) {
dev_err(mmc_dev(host->mmc), "request irq error\n");
goto err_cd_irq_req;
}
}
if (gpio_is_valid(plat->wp_gpio)) {
rc = gpio_request(plat->wp_gpio, "sdhci_wp");
if (rc) {
dev_err(mmc_dev(host->mmc),
"failed to allocate wp gpio\n");
goto err_wp_req;
}
tegra_gpio_enable(plat->wp_gpio);
gpio_direction_input(plat->wp_gpio);
}
clk = clk_get(mmc_dev(host->mmc), NULL);
if (IS_ERR(clk)) {
dev_err(mmc_dev(host->mmc), "clk err\n");
rc = PTR_ERR(clk);
goto err_clk_get;
}
clk_enable(clk);
pltfm_host->clk = clk;
host->mmc->pm_caps = plat->pm_flags;
if (plat->is_8bit)
host->mmc->caps |= MMC_CAP_8_BIT_DATA;
rc = sdhci_add_host(host);
if (rc)
goto err_add_host;
return 0;
err_add_host:
clk_disable(pltfm_host->clk);
clk_put(pltfm_host->clk);
err_clk_get:
if (gpio_is_valid(plat->wp_gpio)) {
tegra_gpio_disable(plat->wp_gpio);
gpio_free(plat->wp_gpio);
}
err_wp_req:
if (gpio_is_valid(plat->cd_gpio))
free_irq(gpio_to_irq(plat->cd_gpio), host);
err_cd_irq_req:
if (gpio_is_valid(plat->cd_gpio)) {
tegra_gpio_disable(plat->cd_gpio);
gpio_free(plat->cd_gpio);
}
err_cd_req:
if (gpio_is_valid(plat->power_gpio)) {
tegra_gpio_disable(plat->power_gpio);
gpio_free(plat->power_gpio);
}
err_power_req:
err_no_plat:
sdhci_pltfm_free(pdev);
return rc;
}
static int __devexit sdhci_tegra_remove(struct platform_device *pdev)
{
struct sdhci_host *host = platform_get_drvdata(pdev);
struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
struct tegra_sdhci_platform_data *plat;
int dead = (readl(host->ioaddr + SDHCI_INT_STATUS) == 0xffffffff);
sdhci_remove_host(host, dead);
plat = pdev->dev.platform_data;
if (gpio_is_valid(plat->wp_gpio)) {
tegra_gpio_disable(plat->wp_gpio);
gpio_free(plat->wp_gpio);
}
if (gpio_is_valid(plat->cd_gpio)) {
free_irq(gpio_to_irq(plat->cd_gpio), host);
tegra_gpio_disable(plat->cd_gpio);
gpio_free(plat->cd_gpio);
}
if (gpio_is_valid(plat->power_gpio)) {
tegra_gpio_disable(plat->power_gpio);
gpio_free(plat->power_gpio);
}
clk_disable(pltfm_host->clk);
clk_put(pltfm_host->clk);
sdhci_pltfm_free(pdev);
return 0;
}
static struct platform_driver sdhci_tegra_driver = {
.driver = {
.name = "sdhci-tegra",
.owner = THIS_MODULE,
},
.probe = sdhci_tegra_probe,
.remove = __devexit_p(sdhci_tegra_remove),
#ifdef CONFIG_PM
.suspend = sdhci_pltfm_suspend,
.resume = sdhci_pltfm_resume,
#endif
};
static int __init sdhci_tegra_init(void)
{
return platform_driver_register(&sdhci_tegra_driver);
}
module_init(sdhci_tegra_init);
static void __exit sdhci_tegra_exit(void)
{
platform_driver_unregister(&sdhci_tegra_driver);
}
module_exit(sdhci_tegra_exit);
MODULE_DESCRIPTION("SDHCI driver for Tegra");
MODULE_AUTHOR(" Google, Inc.");
MODULE_LICENSE("GPL v2");