From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Andr=C3=A9=20Fabian=20Silva=20Delgado?= Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- drivers/mmc/host/sdhci-cns3xxx.c | 115 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 115 insertions(+) create mode 100644 drivers/mmc/host/sdhci-cns3xxx.c (limited to 'drivers/mmc/host/sdhci-cns3xxx.c') diff --git a/drivers/mmc/host/sdhci-cns3xxx.c b/drivers/mmc/host/sdhci-cns3xxx.c new file mode 100644 index 000000000..59f2923f8 --- /dev/null +++ b/drivers/mmc/host/sdhci-cns3xxx.c @@ -0,0 +1,115 @@ +/* + * SDHCI support for CNS3xxx SoC + * + * Copyright 2008 Cavium Networks + * Copyright 2010 MontaVista Software, LLC. + * + * Authors: Scott Shu + * Anton Vorontsov + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include +#include +#include +#include +#include "sdhci-pltfm.h" + +static unsigned int sdhci_cns3xxx_get_max_clk(struct sdhci_host *host) +{ + return 150000000; +} + +static void sdhci_cns3xxx_set_clock(struct sdhci_host *host, unsigned int clock) +{ + struct device *dev = mmc_dev(host->mmc); + int div = 1; + u16 clk; + unsigned long timeout; + + host->mmc->actual_clock = 0; + + sdhci_writew(host, 0, SDHCI_CLOCK_CONTROL); + + if (clock == 0) + return; + + while (host->max_clk / div > clock) { + /* + * On CNS3xxx divider grows linearly up to 4, and then + * exponentially up to 256. + */ + if (div < 4) + div += 1; + else if (div < 256) + div *= 2; + else + break; + } + + dev_dbg(dev, "desired SD clock: %d, actual: %d\n", + clock, host->max_clk / div); + + /* Divide by 3 is special. */ + if (div != 3) + div >>= 1; + + clk = div << SDHCI_DIVIDER_SHIFT; + clk |= SDHCI_CLOCK_INT_EN; + sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL); + + timeout = 20; + while (!((clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL)) + & SDHCI_CLOCK_INT_STABLE)) { + if (timeout == 0) { + dev_warn(dev, "clock is unstable"); + break; + } + timeout--; + mdelay(1); + } + + clk |= SDHCI_CLOCK_CARD_EN; + sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL); +} + +static const struct sdhci_ops sdhci_cns3xxx_ops = { + .get_max_clock = sdhci_cns3xxx_get_max_clk, + .set_clock = sdhci_cns3xxx_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 sdhci_cns3xxx_pdata = { + .ops = &sdhci_cns3xxx_ops, + .quirks = SDHCI_QUIRK_BROKEN_DMA | + SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK | + SDHCI_QUIRK_INVERTED_WRITE_PROTECT | + SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN | + SDHCI_QUIRK_BROKEN_TIMEOUT_VAL, +}; + +static int sdhci_cns3xxx_probe(struct platform_device *pdev) +{ + return sdhci_pltfm_register(pdev, &sdhci_cns3xxx_pdata, 0); +} + +static struct platform_driver sdhci_cns3xxx_driver = { + .driver = { + .name = "sdhci-cns3xxx", + .pm = SDHCI_PLTFM_PMOPS, + }, + .probe = sdhci_cns3xxx_probe, + .remove = sdhci_pltfm_unregister, +}; + +module_platform_driver(sdhci_cns3xxx_driver); + +MODULE_DESCRIPTION("SDHCI driver for CNS3xxx"); +MODULE_AUTHOR("Scott Shu, " + "Anton Vorontsov "); +MODULE_LICENSE("GPL v2"); -- cgit v1.2.3