kernel_samsung_a34x-permissive/drivers/mmc/host/sdhci-tegra.c

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/*
* 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/delay.h>
#include <linux/err.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/reset.h>
#include <linux/mmc/card.h>
#include <linux/mmc/host.h>
#include <linux/mmc/mmc.h>
#include <linux/mmc/slot-gpio.h>
#include <linux/gpio/consumer.h>
#include "sdhci-pltfm.h"
/* Tegra SDHOST controller vendor register definitions */
#define SDHCI_TEGRA_VENDOR_CLOCK_CTRL 0x100
#define SDHCI_CLOCK_CTRL_TAP_MASK 0x00ff0000
#define SDHCI_CLOCK_CTRL_TAP_SHIFT 16
#define SDHCI_CLOCK_CTRL_SDR50_TUNING_OVERRIDE BIT(5)
#define SDHCI_CLOCK_CTRL_PADPIPE_CLKEN_OVERRIDE BIT(3)
#define SDHCI_CLOCK_CTRL_SPI_MODE_CLKEN_OVERRIDE BIT(2)
#define SDHCI_TEGRA_VENDOR_MISC_CTRL 0x120
#define SDHCI_MISC_CTRL_ENABLE_SDR104 0x8
#define SDHCI_MISC_CTRL_ENABLE_SDR50 0x10
#define SDHCI_MISC_CTRL_ENABLE_SDHCI_SPEC_300 0x20
#define SDHCI_MISC_CTRL_ENABLE_DDR50 0x200
#define SDHCI_TEGRA_AUTO_CAL_CONFIG 0x1e4
#define SDHCI_AUTO_CAL_START BIT(31)
#define SDHCI_AUTO_CAL_ENABLE BIT(29)
#define NVQUIRK_FORCE_SDHCI_SPEC_200 BIT(0)
#define NVQUIRK_ENABLE_BLOCK_GAP_DET BIT(1)
#define NVQUIRK_ENABLE_SDHCI_SPEC_300 BIT(2)
#define NVQUIRK_ENABLE_SDR50 BIT(3)
#define NVQUIRK_ENABLE_SDR104 BIT(4)
#define NVQUIRK_ENABLE_DDR50 BIT(5)
#define NVQUIRK_HAS_PADCALIB BIT(6)
struct sdhci_tegra_soc_data {
const struct sdhci_pltfm_data *pdata;
u32 nvquirks;
};
struct sdhci_tegra {
const struct sdhci_tegra_soc_data *soc_data;
struct gpio_desc *power_gpio;
bool ddr_signaling;
bool pad_calib_required;
struct reset_control *rst;
};
static u16 tegra_sdhci_readw(struct sdhci_host *host, int reg)
{
struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
const struct sdhci_tegra_soc_data *soc_data = tegra_host->soc_data;
if (unlikely((soc_data->nvquirks & NVQUIRK_FORCE_SDHCI_SPEC_200) &&
(reg == SDHCI_HOST_VERSION))) {
/* Erratum: Version register is invalid in HW. */
return SDHCI_SPEC_200;
}
return readw(host->ioaddr + reg);
}
static void tegra_sdhci_writew(struct sdhci_host *host, u16 val, int reg)
{
struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
switch (reg) {
case SDHCI_TRANSFER_MODE:
/*
* Postpone this write, we must do it together with a
* command write that is down below.
*/
pltfm_host->xfer_mode_shadow = val;
return;
case SDHCI_COMMAND:
writel((val << 16) | pltfm_host->xfer_mode_shadow,
host->ioaddr + SDHCI_TRANSFER_MODE);
return;
}
writew(val, host->ioaddr + reg);
}
static void tegra_sdhci_writel(struct sdhci_host *host, u32 val, int reg)
{
struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
const struct sdhci_tegra_soc_data *soc_data = tegra_host->soc_data;
/* 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((soc_data->nvquirks & NVQUIRK_ENABLE_BLOCK_GAP_DET) &&
(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 *host)
{
return mmc_gpio_get_ro(host->mmc);
}
static void tegra_sdhci_reset(struct sdhci_host *host, u8 mask)
{
struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
const struct sdhci_tegra_soc_data *soc_data = tegra_host->soc_data;
u32 misc_ctrl, clk_ctrl;
sdhci_reset(host, mask);
if (!(mask & SDHCI_RESET_ALL))
return;
misc_ctrl = sdhci_readl(host, SDHCI_TEGRA_VENDOR_MISC_CTRL);
clk_ctrl = sdhci_readl(host, SDHCI_TEGRA_VENDOR_CLOCK_CTRL);
misc_ctrl &= ~(SDHCI_MISC_CTRL_ENABLE_SDHCI_SPEC_300 |
SDHCI_MISC_CTRL_ENABLE_SDR50 |
SDHCI_MISC_CTRL_ENABLE_DDR50 |
SDHCI_MISC_CTRL_ENABLE_SDR104);
clk_ctrl &= ~SDHCI_CLOCK_CTRL_SPI_MODE_CLKEN_OVERRIDE;
/*
* If the board does not define a regulator for the SDHCI
* IO voltage, then don't advertise support for UHS modes
* even if the device supports it because the IO voltage
* cannot be configured.
*/
if (!IS_ERR(host->mmc->supply.vqmmc)) {
/* Erratum: Enable SDHCI spec v3.00 support */
if (soc_data->nvquirks & NVQUIRK_ENABLE_SDHCI_SPEC_300)
misc_ctrl |= SDHCI_MISC_CTRL_ENABLE_SDHCI_SPEC_300;
/* Advertise UHS modes as supported by host */
if (soc_data->nvquirks & NVQUIRK_ENABLE_SDR50)
misc_ctrl |= SDHCI_MISC_CTRL_ENABLE_SDR50;
if (soc_data->nvquirks & NVQUIRK_ENABLE_DDR50)
misc_ctrl |= SDHCI_MISC_CTRL_ENABLE_DDR50;
if (soc_data->nvquirks & NVQUIRK_ENABLE_SDR104)
misc_ctrl |= SDHCI_MISC_CTRL_ENABLE_SDR104;
if (soc_data->nvquirks & NVQUIRK_ENABLE_SDR50)
clk_ctrl |= SDHCI_CLOCK_CTRL_SDR50_TUNING_OVERRIDE;
}
sdhci_writel(host, misc_ctrl, SDHCI_TEGRA_VENDOR_MISC_CTRL);
sdhci_writel(host, clk_ctrl, SDHCI_TEGRA_VENDOR_CLOCK_CTRL);
if (soc_data->nvquirks & NVQUIRK_HAS_PADCALIB)
tegra_host->pad_calib_required = true;
tegra_host->ddr_signaling = false;
}
static void tegra_sdhci_pad_autocalib(struct sdhci_host *host)
{
u32 val;
mdelay(1);
val = sdhci_readl(host, SDHCI_TEGRA_AUTO_CAL_CONFIG);
val |= SDHCI_AUTO_CAL_ENABLE | SDHCI_AUTO_CAL_START;
sdhci_writel(host,val, SDHCI_TEGRA_AUTO_CAL_CONFIG);
}
static void tegra_sdhci_set_clock(struct sdhci_host *host, unsigned int clock)
{
struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
unsigned long host_clk;
if (!clock)
return sdhci_set_clock(host, clock);
/*
* In DDR50/52 modes the Tegra SDHCI controllers require the SDHCI
* divider to be configured to divided the host clock by two. The SDHCI
* clock divider is calculated as part of sdhci_set_clock() by
* sdhci_calc_clk(). The divider is calculated from host->max_clk and
* the requested clock rate.
*
* By setting the host->max_clk to clock * 2 the divider calculation
* will always result in the correct value for DDR50/52 modes,
* regardless of clock rate rounding, which may happen if the value
* from clk_get_rate() is used.
*/
host_clk = tegra_host->ddr_signaling ? clock * 2 : clock;
clk_set_rate(pltfm_host->clk, host_clk);
if (tegra_host->ddr_signaling)
host->max_clk = host_clk;
else
host->max_clk = clk_get_rate(pltfm_host->clk);
sdhci_set_clock(host, clock);
if (tegra_host->pad_calib_required) {
tegra_sdhci_pad_autocalib(host);
tegra_host->pad_calib_required = false;
}
}
static void tegra_sdhci_set_uhs_signaling(struct sdhci_host *host,
unsigned timing)
{
struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
if (timing == MMC_TIMING_UHS_DDR50 ||
timing == MMC_TIMING_MMC_DDR52)
tegra_host->ddr_signaling = true;
sdhci_set_uhs_signaling(host, timing);
}
static unsigned int tegra_sdhci_get_max_clock(struct sdhci_host *host)
{
struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
return clk_round_rate(pltfm_host->clk, UINT_MAX);
}
static void tegra_sdhci_set_tap(struct sdhci_host *host, unsigned int tap)
{
u32 reg;
reg = sdhci_readl(host, SDHCI_TEGRA_VENDOR_CLOCK_CTRL);
reg &= ~SDHCI_CLOCK_CTRL_TAP_MASK;
reg |= tap << SDHCI_CLOCK_CTRL_TAP_SHIFT;
sdhci_writel(host, reg, SDHCI_TEGRA_VENDOR_CLOCK_CTRL);
}
static int tegra_sdhci_execute_tuning(struct sdhci_host *host, u32 opcode)
{
unsigned int min, max;
/*
* Start search for minimum tap value at 10, as smaller values are
* may wrongly be reported as working but fail at higher speeds,
* according to the TRM.
*/
min = 10;
while (min < 255) {
tegra_sdhci_set_tap(host, min);
if (!mmc_send_tuning(host->mmc, opcode, NULL))
break;
min++;
}
/* Find the maximum tap value that still passes. */
max = min + 1;
while (max < 255) {
tegra_sdhci_set_tap(host, max);
if (mmc_send_tuning(host->mmc, opcode, NULL)) {
max--;
break;
}
max++;
}
/* The TRM states the ideal tap value is at 75% in the passing range. */
tegra_sdhci_set_tap(host, min + ((max - min) * 3 / 4));
return mmc_send_tuning(host->mmc, opcode, NULL);
}
static void tegra_sdhci_voltage_switch(struct sdhci_host *host)
{
struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
const struct sdhci_tegra_soc_data *soc_data = tegra_host->soc_data;
if (soc_data->nvquirks & NVQUIRK_HAS_PADCALIB)
tegra_host->pad_calib_required = true;
}
static const struct sdhci_ops tegra_sdhci_ops = {
.get_ro = tegra_sdhci_get_ro,
.read_w = tegra_sdhci_readw,
.write_l = tegra_sdhci_writel,
.set_clock = tegra_sdhci_set_clock,
.set_bus_width = sdhci_set_bus_width,
.reset = tegra_sdhci_reset,
.platform_execute_tuning = tegra_sdhci_execute_tuning,
.set_uhs_signaling = tegra_sdhci_set_uhs_signaling,
.voltage_switch = tegra_sdhci_voltage_switch,
.get_max_clock = tegra_sdhci_get_max_clock,
};
static const struct sdhci_pltfm_data sdhci_tegra20_pdata = {
.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
SDHCI_QUIRK_SINGLE_POWER_WRITE |
SDHCI_QUIRK_NO_HISPD_BIT |
SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC |
SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
.ops = &tegra_sdhci_ops,
};
static const struct sdhci_tegra_soc_data soc_data_tegra20 = {
.pdata = &sdhci_tegra20_pdata,
.nvquirks = NVQUIRK_FORCE_SDHCI_SPEC_200 |
NVQUIRK_ENABLE_BLOCK_GAP_DET,
};
static const struct sdhci_pltfm_data sdhci_tegra30_pdata = {
.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
SDHCI_QUIRK_SINGLE_POWER_WRITE |
SDHCI_QUIRK_NO_HISPD_BIT |
SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC |
SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
.quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN |
SDHCI_QUIRK2_BROKEN_HS200 |
/*
* Auto-CMD23 leads to "Got command interrupt 0x00010000 even
* though no command operation was in progress."
*
* The exact reason is unknown, as the same hardware seems
* to support Auto CMD23 on a downstream 3.1 kernel.
*/
SDHCI_QUIRK2_ACMD23_BROKEN,
.ops = &tegra_sdhci_ops,
};
static const struct sdhci_tegra_soc_data soc_data_tegra30 = {
.pdata = &sdhci_tegra30_pdata,
.nvquirks = NVQUIRK_ENABLE_SDHCI_SPEC_300 |
NVQUIRK_ENABLE_SDR50 |
NVQUIRK_ENABLE_SDR104 |
NVQUIRK_HAS_PADCALIB,
};
static const struct sdhci_ops tegra114_sdhci_ops = {
.get_ro = tegra_sdhci_get_ro,
.read_w = tegra_sdhci_readw,
.write_w = tegra_sdhci_writew,
.write_l = tegra_sdhci_writel,
.set_clock = tegra_sdhci_set_clock,
.set_bus_width = sdhci_set_bus_width,
.reset = tegra_sdhci_reset,
.platform_execute_tuning = tegra_sdhci_execute_tuning,
.set_uhs_signaling = tegra_sdhci_set_uhs_signaling,
.voltage_switch = tegra_sdhci_voltage_switch,
.get_max_clock = tegra_sdhci_get_max_clock,
};
static const struct sdhci_pltfm_data sdhci_tegra114_pdata = {
.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
SDHCI_QUIRK_SINGLE_POWER_WRITE |
SDHCI_QUIRK_NO_HISPD_BIT |
SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC |
SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
.quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN,
.ops = &tegra114_sdhci_ops,
};
static const struct sdhci_tegra_soc_data soc_data_tegra114 = {
.pdata = &sdhci_tegra114_pdata,
};
static const struct sdhci_pltfm_data sdhci_tegra124_pdata = {
.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
SDHCI_QUIRK_SINGLE_POWER_WRITE |
SDHCI_QUIRK_NO_HISPD_BIT |
SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC |
SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
.quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN |
/*
* The TRM states that the SD/MMC controller found on
* Tegra124 can address 34 bits (the maximum supported by
* the Tegra memory controller), but tests show that DMA
* to or from above 4 GiB doesn't work. This is possibly
* caused by missing programming, though it's not obvious
* what sequence is required. Mark 64-bit DMA broken for
* now to fix this for existing users (e.g. Nyan boards).
*/
SDHCI_QUIRK2_BROKEN_64_BIT_DMA,
.ops = &tegra114_sdhci_ops,
};
static const struct sdhci_tegra_soc_data soc_data_tegra124 = {
.pdata = &sdhci_tegra124_pdata,
};
static const struct sdhci_pltfm_data sdhci_tegra210_pdata = {
.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
SDHCI_QUIRK_SINGLE_POWER_WRITE |
SDHCI_QUIRK_NO_HISPD_BIT |
SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC |
SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
.quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN,
.ops = &tegra114_sdhci_ops,
};
static const struct sdhci_tegra_soc_data soc_data_tegra210 = {
.pdata = &sdhci_tegra210_pdata,
};
static const struct sdhci_pltfm_data sdhci_tegra186_pdata = {
.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
SDHCI_QUIRK_SINGLE_POWER_WRITE |
SDHCI_QUIRK_NO_HISPD_BIT |
SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC |
SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
.quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN |
/* SDHCI controllers on Tegra186 support 40-bit addressing.
* IOVA addresses are 48-bit wide on Tegra186.
* With 64-bit dma mask used for SDHCI, accesses can
* be broken. Disable 64-bit dma, which would fall back
* to 32-bit dma mask. Ideally 40-bit dma mask would work,
* But it is not supported as of now.
*/
SDHCI_QUIRK2_BROKEN_64_BIT_DMA,
.ops = &tegra114_sdhci_ops,
};
static const struct sdhci_tegra_soc_data soc_data_tegra186 = {
.pdata = &sdhci_tegra186_pdata,
};
static const struct of_device_id sdhci_tegra_dt_match[] = {
{ .compatible = "nvidia,tegra186-sdhci", .data = &soc_data_tegra186 },
{ .compatible = "nvidia,tegra210-sdhci", .data = &soc_data_tegra210 },
{ .compatible = "nvidia,tegra124-sdhci", .data = &soc_data_tegra124 },
{ .compatible = "nvidia,tegra114-sdhci", .data = &soc_data_tegra114 },
{ .compatible = "nvidia,tegra30-sdhci", .data = &soc_data_tegra30 },
{ .compatible = "nvidia,tegra20-sdhci", .data = &soc_data_tegra20 },
{}
};
MODULE_DEVICE_TABLE(of, sdhci_tegra_dt_match);
static int sdhci_tegra_probe(struct platform_device *pdev)
{
const struct of_device_id *match;
const struct sdhci_tegra_soc_data *soc_data;
struct sdhci_host *host;
struct sdhci_pltfm_host *pltfm_host;
struct sdhci_tegra *tegra_host;
struct clk *clk;
int rc;
match = of_match_device(sdhci_tegra_dt_match, &pdev->dev);
if (!match)
return -EINVAL;
soc_data = match->data;
host = sdhci_pltfm_init(pdev, soc_data->pdata, sizeof(*tegra_host));
if (IS_ERR(host))
return PTR_ERR(host);
pltfm_host = sdhci_priv(host);
tegra_host = sdhci_pltfm_priv(pltfm_host);
tegra_host->ddr_signaling = false;
tegra_host->pad_calib_required = false;
tegra_host->soc_data = soc_data;
rc = mmc_of_parse(host->mmc);
if (rc)
goto err_parse_dt;
if (tegra_host->soc_data->nvquirks & NVQUIRK_ENABLE_DDR50)
host->mmc->caps |= MMC_CAP_1_8V_DDR;
/* R1B responses is required to properly manage HW busy detection. */
host->mmc->caps |= MMC_CAP_NEED_RSP_BUSY;
tegra_host->power_gpio = devm_gpiod_get_optional(&pdev->dev, "power",
GPIOD_OUT_HIGH);
if (IS_ERR(tegra_host->power_gpio)) {
rc = PTR_ERR(tegra_host->power_gpio);
goto err_power_req;
}
clk = devm_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_prepare_enable(clk);
pltfm_host->clk = clk;
tegra_host->rst = devm_reset_control_get_exclusive(&pdev->dev,
"sdhci");
if (IS_ERR(tegra_host->rst)) {
rc = PTR_ERR(tegra_host->rst);
dev_err(&pdev->dev, "failed to get reset control: %d\n", rc);
goto err_rst_get;
}
rc = reset_control_assert(tegra_host->rst);
if (rc)
goto err_rst_get;
usleep_range(2000, 4000);
rc = reset_control_deassert(tegra_host->rst);
if (rc)
goto err_rst_get;
usleep_range(2000, 4000);
rc = sdhci_add_host(host);
if (rc)
goto err_add_host;
return 0;
err_add_host:
reset_control_assert(tegra_host->rst);
err_rst_get:
clk_disable_unprepare(pltfm_host->clk);
err_clk_get:
err_power_req:
err_parse_dt:
sdhci_pltfm_free(pdev);
return rc;
}
static int 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 sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
sdhci_remove_host(host, 0);
reset_control_assert(tegra_host->rst);
usleep_range(2000, 4000);
clk_disable_unprepare(pltfm_host->clk);
sdhci_pltfm_free(pdev);
return 0;
}
static struct platform_driver sdhci_tegra_driver = {
.driver = {
.name = "sdhci-tegra",
.of_match_table = sdhci_tegra_dt_match,
.pm = &sdhci_pltfm_pmops,
},
.probe = sdhci_tegra_probe,
.remove = sdhci_tegra_remove,
};
module_platform_driver(sdhci_tegra_driver);
MODULE_DESCRIPTION("SDHCI driver for Tegra");
MODULE_AUTHOR("Google, Inc.");
MODULE_LICENSE("GPL v2");