linux/drivers/mmc/host/sdhci-of-at91.c

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/*
* Atmel SDMMC controller driver.
*
* Copyright (C) 2015 Atmel,
* 2015 Ludovic Desroches <ludovic.desroches@atmel.com>
*
* 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/clk.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/mmc/host.h>
#include <linux/mmc/slot-gpio.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/pm.h>
#include <linux/pm_runtime.h>
#include "sdhci-pltfm.h"
#define SDMMC_CACR 0x230
#define SDMMC_CACR_CAPWREN BIT(0)
#define SDMMC_CACR_KEY (0x46 << 8)
#define SDHCI_AT91_PRESET_COMMON_CONF 0x400 /* drv type B, programmable clock mode */
struct sdhci_at91_priv {
struct clk *hclock;
struct clk *gck;
struct clk *mainck;
};
static void sdhci_at91_set_clock(struct sdhci_host *host, unsigned int clock)
{
u16 clk;
unsigned long timeout;
host->mmc->actual_clock = 0;
/*
* There is no requirement to disable the internal clock before
* changing the SD clock configuration. Moreover, disabling the
* internal clock, changing the configuration and re-enabling the
* internal clock causes some bugs. It can prevent to get the internal
* clock stable flag ready and an unexpected switch to the base clock
* when using presets.
*/
clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
clk &= SDHCI_CLOCK_INT_EN;
sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
if (clock == 0)
return;
clk = sdhci_calc_clk(host, clock, &host->mmc->actual_clock);
clk |= SDHCI_CLOCK_INT_EN;
sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
/* Wait max 20 ms */
timeout = 20;
while (!((clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL))
& SDHCI_CLOCK_INT_STABLE)) {
if (timeout == 0) {
pr_err("%s: Internal clock never stabilised.\n",
mmc_hostname(host->mmc));
return;
}
timeout--;
mdelay(1);
}
clk |= SDHCI_CLOCK_CARD_EN;
sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
}
static const struct sdhci_ops sdhci_at91_sama5d2_ops = {
.set_clock = sdhci_at91_set_clock,
.set_bus_width = sdhci_set_bus_width,
.reset = sdhci_reset,
.set_uhs_signaling = sdhci_set_uhs_signaling,
};
static const struct sdhci_pltfm_data soc_data_sama5d2 = {
.ops = &sdhci_at91_sama5d2_ops,
};
static const struct of_device_id sdhci_at91_dt_match[] = {
{ .compatible = "atmel,sama5d2-sdhci", .data = &soc_data_sama5d2 },
{}
};
#ifdef CONFIG_PM
static int sdhci_at91_runtime_suspend(struct device *dev)
{
struct sdhci_host *host = dev_get_drvdata(dev);
struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
struct sdhci_at91_priv *priv = sdhci_pltfm_priv(pltfm_host);
int ret;
ret = sdhci_runtime_suspend_host(host);
clk_disable_unprepare(priv->gck);
clk_disable_unprepare(priv->hclock);
clk_disable_unprepare(priv->mainck);
return ret;
}
static int sdhci_at91_runtime_resume(struct device *dev)
{
struct sdhci_host *host = dev_get_drvdata(dev);
struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
struct sdhci_at91_priv *priv = sdhci_pltfm_priv(pltfm_host);
int ret;
ret = clk_prepare_enable(priv->mainck);
if (ret) {
dev_err(dev, "can't enable mainck\n");
return ret;
}
ret = clk_prepare_enable(priv->hclock);
if (ret) {
dev_err(dev, "can't enable hclock\n");
return ret;
}
ret = clk_prepare_enable(priv->gck);
if (ret) {
dev_err(dev, "can't enable gck\n");
return ret;
}
return sdhci_runtime_resume_host(host);
}
#endif /* CONFIG_PM */
static const struct dev_pm_ops sdhci_at91_dev_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
pm_runtime_force_resume)
SET_RUNTIME_PM_OPS(sdhci_at91_runtime_suspend,
sdhci_at91_runtime_resume,
NULL)
};
static int sdhci_at91_probe(struct platform_device *pdev)
{
const struct of_device_id *match;
const struct sdhci_pltfm_data *soc_data;
struct sdhci_host *host;
struct sdhci_pltfm_host *pltfm_host;
struct sdhci_at91_priv *priv;
unsigned int caps0, caps1;
unsigned int clk_base, clk_mul;
unsigned int gck_rate, real_gck_rate;
int ret;
unsigned int preset_div;
match = of_match_device(sdhci_at91_dt_match, &pdev->dev);
if (!match)
return -EINVAL;
soc_data = match->data;
host = sdhci_pltfm_init(pdev, soc_data, sizeof(*priv));
if (IS_ERR(host))
return PTR_ERR(host);
pltfm_host = sdhci_priv(host);
priv = sdhci_pltfm_priv(pltfm_host);
priv->mainck = devm_clk_get(&pdev->dev, "baseclk");
if (IS_ERR(priv->mainck)) {
dev_err(&pdev->dev, "failed to get baseclk\n");
return PTR_ERR(priv->mainck);
}
priv->hclock = devm_clk_get(&pdev->dev, "hclock");
if (IS_ERR(priv->hclock)) {
dev_err(&pdev->dev, "failed to get hclock\n");
return PTR_ERR(priv->hclock);
}
priv->gck = devm_clk_get(&pdev->dev, "multclk");
if (IS_ERR(priv->gck)) {
dev_err(&pdev->dev, "failed to get multclk\n");
return PTR_ERR(priv->gck);
}
/*
* The mult clock is provided by as a generated clock by the PMC
* controller. In order to set the rate of gck, we have to get the
* base clock rate and the clock mult from capabilities.
*/
clk_prepare_enable(priv->hclock);
caps0 = readl(host->ioaddr + SDHCI_CAPABILITIES);
caps1 = readl(host->ioaddr + SDHCI_CAPABILITIES_1);
clk_base = (caps0 & SDHCI_CLOCK_V3_BASE_MASK) >> SDHCI_CLOCK_BASE_SHIFT;
clk_mul = (caps1 & SDHCI_CLOCK_MUL_MASK) >> SDHCI_CLOCK_MUL_SHIFT;
gck_rate = clk_base * 1000000 * (clk_mul + 1);
ret = clk_set_rate(priv->gck, gck_rate);
if (ret < 0) {
dev_err(&pdev->dev, "failed to set gck");
goto hclock_disable_unprepare;
}
/*
* We need to check if we have the requested rate for gck because in
* some cases this rate could be not supported. If it happens, the rate
* is the closest one gck can provide. We have to update the value
* of clk mul.
*/
real_gck_rate = clk_get_rate(priv->gck);
if (real_gck_rate != gck_rate) {
clk_mul = real_gck_rate / (clk_base * 1000000) - 1;
caps1 &= (~SDHCI_CLOCK_MUL_MASK);
caps1 |= ((clk_mul << SDHCI_CLOCK_MUL_SHIFT) & SDHCI_CLOCK_MUL_MASK);
/* Set capabilities in r/w mode. */
writel(SDMMC_CACR_KEY | SDMMC_CACR_CAPWREN, host->ioaddr + SDMMC_CACR);
writel(caps1, host->ioaddr + SDHCI_CAPABILITIES_1);
/* Set capabilities in ro mode. */
writel(0, host->ioaddr + SDMMC_CACR);
dev_info(&pdev->dev, "update clk mul to %u as gck rate is %u Hz\n",
clk_mul, real_gck_rate);
}
/*
* We have to set preset values because it depends on the clk_mul
* value. Moreover, SDR104 is supported in a degraded mode since the
* maximum sd clock value is 120 MHz instead of 208 MHz. For that
* reason, we need to use presets to support SDR104.
*/
preset_div = DIV_ROUND_UP(real_gck_rate, 24000000) - 1;
writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div,
host->ioaddr + SDHCI_PRESET_FOR_SDR12);
preset_div = DIV_ROUND_UP(real_gck_rate, 50000000) - 1;
writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div,
host->ioaddr + SDHCI_PRESET_FOR_SDR25);
preset_div = DIV_ROUND_UP(real_gck_rate, 100000000) - 1;
writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div,
host->ioaddr + SDHCI_PRESET_FOR_SDR50);
preset_div = DIV_ROUND_UP(real_gck_rate, 120000000) - 1;
writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div,
host->ioaddr + SDHCI_PRESET_FOR_SDR104);
preset_div = DIV_ROUND_UP(real_gck_rate, 50000000) - 1;
writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div,
host->ioaddr + SDHCI_PRESET_FOR_DDR50);
clk_prepare_enable(priv->mainck);
clk_prepare_enable(priv->gck);
ret = mmc_of_parse(host->mmc);
if (ret)
goto clocks_disable_unprepare;
sdhci_get_of_property(pdev);
pm_runtime_get_noresume(&pdev->dev);
pm_runtime_set_active(&pdev->dev);
pm_runtime_enable(&pdev->dev);
pm_runtime_set_autosuspend_delay(&pdev->dev, 50);
pm_runtime_use_autosuspend(&pdev->dev);
ret = sdhci_add_host(host);
if (ret)
goto pm_runtime_disable;
/*
* When calling sdhci_runtime_suspend_host(), the sdhci layer makes
* the assumption that all the clocks of the controller are disabled.
* It means we can't get irq from it when it is runtime suspended.
* For that reason, it is not planned to wake-up on a card detect irq
* from the controller.
* If we want to use runtime PM and to be able to wake-up on card
* insertion, we have to use a GPIO for the card detection or we can
* use polling. Be aware that using polling will resume/suspend the
* controller between each attempt.
* Disable SDHCI_QUIRK_BROKEN_CARD_DETECTION to be sure nobody tries
* to enable polling via device tree with broken-cd property.
*/
if (!(host->mmc->caps & MMC_CAP_NONREMOVABLE) &&
remove lots of IS_ERR_VALUE abuses Most users of IS_ERR_VALUE() in the kernel are wrong, as they pass an 'int' into a function that takes an 'unsigned long' argument. This happens to work because the type is sign-extended on 64-bit architectures before it gets converted into an unsigned type. However, anything that passes an 'unsigned short' or 'unsigned int' argument into IS_ERR_VALUE() is guaranteed to be broken, as are 8-bit integers and types that are wider than 'unsigned long'. Andrzej Hajda has already fixed a lot of the worst abusers that were causing actual bugs, but it would be nice to prevent any users that are not passing 'unsigned long' arguments. This patch changes all users of IS_ERR_VALUE() that I could find on 32-bit ARM randconfig builds and x86 allmodconfig. For the moment, this doesn't change the definition of IS_ERR_VALUE() because there are probably still architecture specific users elsewhere. Almost all the warnings I got are for files that are better off using 'if (err)' or 'if (err < 0)'. The only legitimate user I could find that we get a warning for is the (32-bit only) freescale fman driver, so I did not remove the IS_ERR_VALUE() there but changed the type to 'unsigned long'. For 9pfs, I just worked around one user whose calling conventions are so obscure that I did not dare change the behavior. I was using this definition for testing: #define IS_ERR_VALUE(x) ((unsigned long*)NULL == (typeof (x)*)NULL && \ unlikely((unsigned long long)(x) >= (unsigned long long)(typeof(x))-MAX_ERRNO)) which ends up making all 16-bit or wider types work correctly with the most plausible interpretation of what IS_ERR_VALUE() was supposed to return according to its users, but also causes a compile-time warning for any users that do not pass an 'unsigned long' argument. I suggested this approach earlier this year, but back then we ended up deciding to just fix the users that are obviously broken. After the initial warning that caused me to get involved in the discussion (fs/gfs2/dir.c) showed up again in the mainline kernel, Linus asked me to send the whole thing again. [ Updated the 9p parts as per Al Viro - Linus ] Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Andrzej Hajda <a.hajda@samsung.com> Cc: Andrew Morton <akpm@linux-foundation.org> Link: https://lkml.org/lkml/2016/1/7/363 Link: https://lkml.org/lkml/2016/5/27/486 Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> # For nvmem part Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-28 05:23:25 +08:00
mmc_gpio_get_cd(host->mmc) < 0) {
host->mmc->caps |= MMC_CAP_NEEDS_POLL;
host->quirks &= ~SDHCI_QUIRK_BROKEN_CARD_DETECTION;
}
pm_runtime_put_autosuspend(&pdev->dev);
return 0;
pm_runtime_disable:
pm_runtime_disable(&pdev->dev);
pm_runtime_set_suspended(&pdev->dev);
pm_runtime_put_noidle(&pdev->dev);
clocks_disable_unprepare:
clk_disable_unprepare(priv->gck);
clk_disable_unprepare(priv->mainck);
hclock_disable_unprepare:
clk_disable_unprepare(priv->hclock);
sdhci_pltfm_free(pdev);
return ret;
}
static int sdhci_at91_remove(struct platform_device *pdev)
{
struct sdhci_host *host = platform_get_drvdata(pdev);
struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
struct sdhci_at91_priv *priv = sdhci_pltfm_priv(pltfm_host);
struct clk *gck = priv->gck;
struct clk *hclock = priv->hclock;
struct clk *mainck = priv->mainck;
pm_runtime_get_sync(&pdev->dev);
pm_runtime_disable(&pdev->dev);
pm_runtime_put_noidle(&pdev->dev);
sdhci_pltfm_unregister(pdev);
clk_disable_unprepare(gck);
clk_disable_unprepare(hclock);
clk_disable_unprepare(mainck);
return 0;
}
static struct platform_driver sdhci_at91_driver = {
.driver = {
.name = "sdhci-at91",
.of_match_table = sdhci_at91_dt_match,
.pm = &sdhci_at91_dev_pm_ops,
},
.probe = sdhci_at91_probe,
.remove = sdhci_at91_remove,
};
module_platform_driver(sdhci_at91_driver);
MODULE_DESCRIPTION("SDHCI driver for at91");
MODULE_AUTHOR("Ludovic Desroches <ludovic.desroches@atmel.com>");
MODULE_LICENSE("GPL v2");