diff options
Diffstat (limited to 'drivers/mmc/host/sdhci-bcm2835.c')
| -rw-r--r-- | drivers/mmc/host/sdhci-bcm2835.c | 204 |
1 files changed, 0 insertions, 204 deletions
diff --git a/drivers/mmc/host/sdhci-bcm2835.c b/drivers/mmc/host/sdhci-bcm2835.c deleted file mode 100644 index 4a6a1d138..000000000 --- a/drivers/mmc/host/sdhci-bcm2835.c +++ /dev/null @@ -1,204 +0,0 @@ -/* - * BCM2835 SDHCI - * Copyright (C) 2012 Stephen Warren - * Based on U-Boot's MMC driver for the BCM2835 by Oleksandr Tymoshenko & me - * Portions of the code there were obviously based on the Linux kernel at: - * git://github.com/raspberrypi/linux.git rpi-3.6.y - * commit f5b930b "Main bcm2708 linux port" signed-off-by Dom Cobley. - * - * This program is free software; you can redistribute it and/or modify it - * under the terms and conditions of the GNU General Public License, - * version 2, as published by the Free Software Foundation. - * - * This program is distributed in the hope 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. - * - * You should have received a copy of the GNU General Public License - * along with this program. If not, see <http://www.gnu.org/licenses/>. - */ - -#include <linux/delay.h> -#include <linux/module.h> -#include <linux/mmc/host.h> -#include "sdhci-pltfm.h" - -/* - * 400KHz is max freq for card ID etc. Use that as min card clock. We need to - * know the min to enable static calculation of max BCM2835_SDHCI_WRITE_DELAY. - */ -#define MIN_FREQ 400000 - -/* - * The Arasan has a bugette whereby it may lose the content of successive - * writes to registers that are within two SD-card clock cycles of each other - * (a clock domain crossing problem). It seems, however, that the data - * register does not have this problem, which is just as well - otherwise we'd - * have to nobble the DMA engine too. - * - * This should probably be dynamically calculated based on the actual card - * frequency. However, this is the longest we'll have to wait, and doesn't - * seem to slow access down too much, so the added complexity doesn't seem - * worth it for now. - * - * 1/MIN_FREQ is (max) time per tick of eMMC clock. - * 2/MIN_FREQ is time for two ticks. - * Multiply by 1000000 to get uS per two ticks. - * *1000000 for uSecs. - * +1 for hack rounding. - */ -#define BCM2835_SDHCI_WRITE_DELAY (((2 * 1000000) / MIN_FREQ) + 1) - -struct bcm2835_sdhci { - u32 shadow; -}; - -static void bcm2835_sdhci_writel(struct sdhci_host *host, u32 val, int reg) -{ - writel(val, host->ioaddr + reg); - - udelay(BCM2835_SDHCI_WRITE_DELAY); -} - -static inline u32 bcm2835_sdhci_readl(struct sdhci_host *host, int reg) -{ - u32 val = readl(host->ioaddr + reg); - - if (reg == SDHCI_CAPABILITIES) - val |= SDHCI_CAN_VDD_330; - - return val; -} - -static void bcm2835_sdhci_writew(struct sdhci_host *host, u16 val, int reg) -{ - struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host); - struct bcm2835_sdhci *bcm2835_host = sdhci_pltfm_priv(pltfm_host); - u32 oldval = (reg == SDHCI_COMMAND) ? bcm2835_host->shadow : - bcm2835_sdhci_readl(host, reg & ~3); - u32 word_num = (reg >> 1) & 1; - u32 word_shift = word_num * 16; - u32 mask = 0xffff << word_shift; - u32 newval = (oldval & ~mask) | (val << word_shift); - - if (reg == SDHCI_TRANSFER_MODE) - bcm2835_host->shadow = newval; - else - bcm2835_sdhci_writel(host, newval, reg & ~3); -} - -static u16 bcm2835_sdhci_readw(struct sdhci_host *host, int reg) -{ - u32 val = bcm2835_sdhci_readl(host, (reg & ~3)); - u32 word_num = (reg >> 1) & 1; - u32 word_shift = word_num * 16; - u32 word = (val >> word_shift) & 0xffff; - - return word; -} - -static void bcm2835_sdhci_writeb(struct sdhci_host *host, u8 val, int reg) -{ - u32 oldval = bcm2835_sdhci_readl(host, reg & ~3); - u32 byte_num = reg & 3; - u32 byte_shift = byte_num * 8; - u32 mask = 0xff << byte_shift; - u32 newval = (oldval & ~mask) | (val << byte_shift); - - bcm2835_sdhci_writel(host, newval, reg & ~3); -} - -static u8 bcm2835_sdhci_readb(struct sdhci_host *host, int reg) -{ - u32 val = bcm2835_sdhci_readl(host, (reg & ~3)); - u32 byte_num = reg & 3; - u32 byte_shift = byte_num * 8; - u32 byte = (val >> byte_shift) & 0xff; - - return byte; -} - -static unsigned int bcm2835_sdhci_get_min_clock(struct sdhci_host *host) -{ - return MIN_FREQ; -} - -static const struct sdhci_ops bcm2835_sdhci_ops = { - .write_l = bcm2835_sdhci_writel, - .write_w = bcm2835_sdhci_writew, - .write_b = bcm2835_sdhci_writeb, - .read_l = bcm2835_sdhci_readl, - .read_w = bcm2835_sdhci_readw, - .read_b = bcm2835_sdhci_readb, - .set_clock = sdhci_set_clock, - .get_max_clock = sdhci_pltfm_clk_get_max_clock, - .get_min_clock = bcm2835_sdhci_get_min_clock, - .set_bus_width = sdhci_set_bus_width, - .reset = sdhci_reset, - .set_uhs_signaling = sdhci_set_uhs_signaling, -}; - -static const struct sdhci_pltfm_data bcm2835_sdhci_pdata = { - .quirks = SDHCI_QUIRK_BROKEN_CARD_DETECTION | - SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK, - .ops = &bcm2835_sdhci_ops, -}; - -static int bcm2835_sdhci_probe(struct platform_device *pdev) -{ - struct sdhci_host *host; - struct bcm2835_sdhci *bcm2835_host; - struct sdhci_pltfm_host *pltfm_host; - int ret; - - host = sdhci_pltfm_init(pdev, &bcm2835_sdhci_pdata, - sizeof(*bcm2835_host)); - if (IS_ERR(host)) - return PTR_ERR(host); - - pltfm_host = sdhci_priv(host); - - pltfm_host->clk = devm_clk_get(&pdev->dev, NULL); - if (IS_ERR(pltfm_host->clk)) { - ret = PTR_ERR(pltfm_host->clk); - goto err; - } - ret = clk_prepare_enable(pltfm_host->clk); - if (ret) { - dev_err(&pdev->dev, "failed to enable host clk\n"); - goto err; - } - - ret = sdhci_add_host(host); - if (ret) - goto err_clk; - - return 0; -err_clk: - clk_disable_unprepare(pltfm_host->clk); -err: - sdhci_pltfm_free(pdev); - return ret; -} - -static const struct of_device_id bcm2835_sdhci_of_match[] = { - { .compatible = "brcm,bcm2835-sdhci" }, - { } -}; -MODULE_DEVICE_TABLE(of, bcm2835_sdhci_of_match); - -static struct platform_driver bcm2835_sdhci_driver = { - .driver = { - .name = "sdhci-bcm2835", - .of_match_table = bcm2835_sdhci_of_match, - .pm = SDHCI_PLTFM_PMOPS, - }, - .probe = bcm2835_sdhci_probe, - .remove = sdhci_pltfm_unregister, -}; -module_platform_driver(bcm2835_sdhci_driver); - -MODULE_DESCRIPTION("BCM2835 SDHCI driver"); -MODULE_AUTHOR("Stephen Warren"); -MODULE_LICENSE("GPL v2"); |