mmc: bcm281xx SDHCI driver (01ebea1b) · Commits · e / devices / android_kernel_fairphone_FP3

arch/arm/configs/bcm_defconfig

+7 −0

Original line number	Diff line number	Diff line
		@@ -78,6 +78,13 @@ CONFIG_BACKLIGHT_LCD_SUPPORT=y
		CONFIG_LCD_CLASS_DEVICE=y
		CONFIG_BACKLIGHT_CLASS_DEVICE=y
		# CONFIG_USB_SUPPORT is not set
		CONFIG_MMC=y
		CONFIG_MMC_UNSAFE_RESUME=y
		CONFIG_MMC_BLOCK_MINORS=32
		CONFIG_MMC_TEST=y
		CONFIG_MMC_SDHCI=y
		CONFIG_MMC_SDHCI_PLTFM=y
		CONFIG_MMC_SDHCI_BCM_KONA=y
		CONFIG_NEW_LEDS=y
		CONFIG_LEDS_CLASS=y
		CONFIG_LEDS_TRIGGERS=y

drivers/mmc/host/Kconfig

+11 −0

Original line number	Diff line number	Diff line
		@@ -249,6 +249,17 @@ config MMC_SDHCI_S3C_DMA

		YMMV.

		config MMC_SDHCI_BCM_KONA
		tristate "SDHCI support on Broadcom KONA platform"
		depends on ARCH_BCM
		select MMC_SDHCI_PLTFM
		help
		This selects the Broadcom Kona Secure Digital Host Controller
		Interface(SDHCI) support.
		This is used in Broadcom mobile SoCs.

		If you have a controller with this interface, say Y or M here.

		config MMC_SDHCI_BCM2835
		tristate "SDHCI platform support for the BCM2835 SD/MMC Controller"
		depends on ARCH_BCM2835

drivers/mmc/host/Makefile

+1 −0

Original line number	Diff line number	Diff line
		@@ -61,6 +61,7 @@ obj-$(CONFIG_MMC_SDHCI_DOVE) += sdhci-dove.o
		obj-$(CONFIG_MMC_SDHCI_TEGRA) += sdhci-tegra.o
		obj-$(CONFIG_MMC_SDHCI_OF_ESDHC) += sdhci-of-esdhc.o
		obj-$(CONFIG_MMC_SDHCI_OF_HLWD) += sdhci-of-hlwd.o
		obj-$(CONFIG_MMC_SDHCI_BCM_KONA) += sdhci-bcm-kona.o
		obj-$(CONFIG_MMC_SDHCI_BCM2835) += sdhci-bcm2835.o

		ifeq ($(CONFIG_CB710_DEBUG),y)

drivers/mmc/host/sdhci-bcm-kona.c

0 → 100644

+348 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2013 Broadcom Corporation
		*
		* This program is free software; you can redistribute it and/or
		* modify it under the terms of the GNU General Public License as
		* published by the Free Software Foundation version 2.
		*
		* This program is distributed "as is" WITHOUT ANY WARRANTY of any
		* kind, whether express or implied; without even the implied warranty
		* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
		* GNU General Public License for more details.
		*/

		#include <linux/kernel.h>
		#include <linux/module.h>
		#include <linux/delay.h>
		#include <linux/highmem.h>
		#include <linux/platform_device.h>
		#include <linux/mmc/host.h>
		#include <linux/io.h>
		#include <linux/gpio.h>
		#include <linux/clk.h>
		#include <linux/regulator/consumer.h>
		#include <linux/of.h>
		#include <linux/of_device.h>
		#include <linux/of_gpio.h>
		#include <linux/version.h>
		#include <linux/mmc/slot-gpio.h>

		#include "sdhci-pltfm.h"
		#include "sdhci.h"

		#define SDHCI_SOFT_RESET 0x01000000
		#define KONA_SDHOST_CORECTRL 0x8000
		#define KONA_SDHOST_CD_PINCTRL 0x00000008
		#define KONA_SDHOST_STOP_HCLK 0x00000004
		#define KONA_SDHOST_RESET 0x00000002
		#define KONA_SDHOST_EN 0x00000001

		#define KONA_SDHOST_CORESTAT 0x8004
		#define KONA_SDHOST_WP 0x00000002
		#define KONA_SDHOST_CD_SW 0x00000001

		#define KONA_SDHOST_COREIMR 0x8008
		#define KONA_SDHOST_IP 0x00000001

		#define KONA_SDHOST_COREISR 0x800C
		#define KONA_SDHOST_COREIMSR 0x8010
		#define KONA_SDHOST_COREDBG1 0x8014
		#define KONA_SDHOST_COREGPO_MASK 0x8018

		#define SD_DETECT_GPIO_DEBOUNCE_128MS 128

		#define KONA_MMC_AUTOSUSPEND_DELAY (50)

		struct sdhci_bcm_kona_dev {
		struct mutex write_lock; /* protect back to back writes */
		};


		static int sdhci_bcm_kona_sd_reset(struct sdhci_host *host)
		{
		unsigned int val;
		unsigned long timeout;

		/* This timeout should be sufficent for core to reset */
		timeout = jiffies + msecs_to_jiffies(100);

		/* reset the host using the top level reset */
		val = sdhci_readl(host, KONA_SDHOST_CORECTRL);
		val \|= KONA_SDHOST_RESET;
		sdhci_writel(host, val, KONA_SDHOST_CORECTRL);

		while (!(sdhci_readl(host, KONA_SDHOST_CORECTRL) & KONA_SDHOST_RESET)) {
		if (time_is_before_jiffies(timeout)) {
		pr_err("Error: sd host is stuck in reset!!!\n");
		return -EFAULT;
		}
		}

		/* bring the host out of reset */
		val = sdhci_readl(host, KONA_SDHOST_CORECTRL);
		val &= ~KONA_SDHOST_RESET;

		/*
		* Back-to-Back register write needs a delay of 1ms at bootup (min 10uS)
		* Back-to-Back writes to same register needs delay when SD bus clock
		* is very low w.r.t AHB clock, mainly during boot-time and during card
		* insert-removal.
		*/
		usleep_range(1000, 5000);
		sdhci_writel(host, val, KONA_SDHOST_CORECTRL);

		return 0;
		}

		static void sdhci_bcm_kona_sd_init(struct sdhci_host *host)
		{
		unsigned int val;

		/* enable the interrupt from the IP core */
		val = sdhci_readl(host, KONA_SDHOST_COREIMR);
		val \|= KONA_SDHOST_IP;
		sdhci_writel(host, val, KONA_SDHOST_COREIMR);

		/* Enable the AHB clock gating module to the host */
		val = sdhci_readl(host, KONA_SDHOST_CORECTRL);
		val \|= KONA_SDHOST_EN;

		/*
		* Back-to-Back register write needs a delay of 1ms at bootup (min 10uS)
		* Back-to-Back writes to same register needs delay when SD bus clock
		* is very low w.r.t AHB clock, mainly during boot-time and during card
		* insert-removal.
		*/
		usleep_range(1000, 5000);
		sdhci_writel(host, val, KONA_SDHOST_CORECTRL);
		}

		/*
		* Software emulation of the SD card insertion/removal. Set insert=1 for insert
		* and insert=0 for removal. The card detection is done by GPIO. For Broadcom
		* IP to function properly the bit 0 of CORESTAT register needs to be set/reset
		* to generate the CD IRQ handled in sdhci.c which schedules card_tasklet.
		*/
		static int sdhci_bcm_kona_sd_card_emulate(struct sdhci_host *host, int insert)
		{
		struct sdhci_pltfm_host *pltfm_priv = sdhci_priv(host);
		struct sdhci_bcm_kona_dev *kona_dev = sdhci_pltfm_priv(pltfm_priv);
		u32 val;

		/*
		* Back-to-Back register write needs a delay of min 10uS.
		* Back-to-Back writes to same register needs delay when SD bus clock
		* is very low w.r.t AHB clock, mainly during boot-time and during card
		* insert-removal.
		* We keep 20uS
		*/
		mutex_lock(&kona_dev->write_lock);
		udelay(20);
		val = sdhci_readl(host, KONA_SDHOST_CORESTAT);

		if (insert) {
		int ret;

		ret = mmc_gpio_get_ro(host->mmc);
		if (ret >= 0)
		val = (val & ~KONA_SDHOST_WP) \|
		((ret) ? KONA_SDHOST_WP : 0);

		val \|= KONA_SDHOST_CD_SW;
		sdhci_writel(host, val, KONA_SDHOST_CORESTAT);
		} else {
		val &= ~KONA_SDHOST_CD_SW;
		sdhci_writel(host, val, KONA_SDHOST_CORESTAT);
		}
		mutex_unlock(&kona_dev->write_lock);

		return 0;
		}

		/*
		* SD card interrupt event callback
		*/
		void sdhci_bcm_kona_card_event(struct sdhci_host *host)
		{
		if (mmc_gpio_get_cd(host->mmc) > 0) {
		dev_dbg(mmc_dev(host->mmc),
		"card inserted\n");
		sdhci_bcm_kona_sd_card_emulate(host, 1);
		} else {
		dev_dbg(mmc_dev(host->mmc),
		"card removed\n");
		sdhci_bcm_kona_sd_card_emulate(host, 0);
		}
		}

		/*
		* Get the base clock. Use central clock source for now. Not sure if different
		* clock speed to each dev is allowed
		*/
		static unsigned int sdhci_bcm_kona_get_max_clk(struct sdhci_host *host)
		{
		struct sdhci_bcm_kona_dev *kona_dev;
		struct sdhci_pltfm_host *pltfm_priv = sdhci_priv(host);
		kona_dev = sdhci_pltfm_priv(pltfm_priv);

		return host->mmc->f_max;
		}

		static unsigned int sdhci_bcm_kona_get_timeout_clock(struct sdhci_host *host)
		{
		return sdhci_bcm_kona_get_max_clk(host);
		}

		static void sdhci_bcm_kona_init_74_clocks(struct sdhci_host *host,
		u8 power_mode)
		{
		/*
		* JEDEC and SD spec specify supplying 74 continuous clocks to
		* device after power up. With minimum bus (100KHz) that
		* that translates to 740us
		*/
		if (power_mode != MMC_POWER_OFF)
		udelay(740);
		}

		static struct sdhci_ops sdhci_bcm_kona_ops = {
		.get_max_clock = sdhci_bcm_kona_get_max_clk,
		.get_timeout_clock = sdhci_bcm_kona_get_timeout_clock,
		.platform_send_init_74_clocks = sdhci_bcm_kona_init_74_clocks,
		.card_event = sdhci_bcm_kona_card_event,
		};

		static struct sdhci_pltfm_data sdhci_pltfm_data_kona = {
		.ops = &sdhci_bcm_kona_ops,
		.quirks = SDHCI_QUIRK_NO_CARD_NO_RESET \|
		SDHCI_QUIRK_BROKEN_TIMEOUT_VAL \| SDHCI_QUIRK_32BIT_DMA_ADDR \|
		SDHCI_QUIRK_32BIT_DMA_SIZE \| SDHCI_QUIRK_32BIT_ADMA_SIZE \|
		SDHCI_QUIRK_FORCE_BLK_SZ_2048 \|
		SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
		};

		static const struct of_device_id sdhci_bcm_kona_of_match[] __initdata = {
		{ .compatible = "bcm,kona-sdhci"},
		{}
		};
		MODULE_DEVICE_TABLE(of, sdhci_bcm_kona_of_match);

		static int __init sdhci_bcm_kona_probe(struct platform_device *pdev)
		{
		struct sdhci_bcm_kona_dev *kona_dev = NULL;
		struct sdhci_pltfm_host *pltfm_priv;
		struct device *dev = &pdev->dev;
		struct sdhci_host *host;
		int ret;

		ret = 0;

		host = sdhci_pltfm_init(pdev, &sdhci_pltfm_data_kona,
		sizeof(*kona_dev));
		if (IS_ERR(host))
		return PTR_ERR(host);

		dev_dbg(dev, "%s: inited. IOADDR=%p\n", __func__, host->ioaddr);

		pltfm_priv = sdhci_priv(host);

		kona_dev = sdhci_pltfm_priv(pltfm_priv);
		mutex_init(&kona_dev->write_lock);

		mmc_of_parse(host->mmc);

		if (!host->mmc->f_max) {
		dev_err(&pdev->dev, "Missing max-freq for SDHCI cfg\n");
		ret = -ENXIO;
		goto err_pltfm_free;
		}

		dev_dbg(dev, "non-removable=%c\n",
		(host->mmc->caps & MMC_CAP_NONREMOVABLE) ? 'Y' : 'N');
		dev_dbg(dev, "cd_gpio %c, wp_gpio %c\n",
		(mmc_gpio_get_cd(host->mmc) != -ENOSYS) ? 'Y' : 'N',
		(mmc_gpio_get_ro(host->mmc) != -ENOSYS) ? 'Y' : 'N');

		if (host->mmc->caps \| MMC_CAP_NONREMOVABLE)
		host->quirks \|= SDHCI_QUIRK_BROKEN_CARD_DETECTION;

		dev_dbg(dev, "is_8bit=%c\n",
		(host->mmc->caps \| MMC_CAP_8_BIT_DATA) ? 'Y' : 'N');

		ret = sdhci_bcm_kona_sd_reset(host);
		if (ret)
		goto err_pltfm_free;

		sdhci_bcm_kona_sd_init(host);

		ret = sdhci_add_host(host);
		if (ret) {
		dev_err(dev, "Failed sdhci_add_host\n");
		goto err_reset;
		}

		/* if device is eMMC, emulate card insert right here */
		if (host->mmc->caps \| MMC_CAP_NONREMOVABLE) {
		ret = sdhci_bcm_kona_sd_card_emulate(host, 1);
		if (ret) {
		dev_err(dev,
		"unable to emulate card insertion\n");
		goto err_remove_host;
		}
		}
		/*
		* Since the card detection GPIO interrupt is configured to be
		* edge sensitive, check the initial GPIO value here, emulate
		* only if the card is present
		*/
		if (mmc_gpio_get_cd(host->mmc) > 0)
		sdhci_bcm_kona_sd_card_emulate(host, 1);

		dev_dbg(dev, "initialized properly\n");
		return 0;

		err_remove_host:
		sdhci_remove_host(host, 0);

		err_reset:
		sdhci_bcm_kona_sd_reset(host);

		err_pltfm_free:
		sdhci_pltfm_free(pdev);

		dev_err(dev, "Probing of sdhci-pltfm failed: %d\n", ret);
		return ret;
		}

		static int __exit sdhci_bcm_kona_remove(struct platform_device *pdev)
		{
		struct sdhci_host *host = platform_get_drvdata(pdev);
		int dead;
		u32 scratch;

		dead = 0;
		scratch = readl(host->ioaddr + SDHCI_INT_STATUS);
		if (scratch == (u32)-1)
		dead = 1;
		sdhci_remove_host(host, dead);

		sdhci_free_host(host);

		return 0;
		}

		static struct platform_driver sdhci_bcm_kona_driver = {
		.driver = {
		.name = "sdhci-kona",
		.owner = THIS_MODULE,
		.pm = SDHCI_PLTFM_PMOPS,
		.of_match_table = of_match_ptr(sdhci_bcm_kona_of_match),
		},
		.probe = sdhci_bcm_kona_probe,
		.remove = __exit_p(sdhci_bcm_kona_remove),
		};
		module_platform_driver(sdhci_bcm_kona_driver);

		MODULE_DESCRIPTION("SDHCI driver for Broadcom Kona platform");
		MODULE_AUTHOR("Broadcom");
		MODULE_LICENSE("GPL v2");