diff options
Diffstat (limited to 'drivers/mmc/host/sdhci-s3c.c')
| -rw-r--r-- | drivers/mmc/host/sdhci-s3c.c | 294 |
1 files changed, 294 insertions, 0 deletions
diff --git a/drivers/mmc/host/sdhci-s3c.c b/drivers/mmc/host/sdhci-s3c.c new file mode 100644 index 00000000000..554befa1786 --- /dev/null +++ b/drivers/mmc/host/sdhci-s3c.c @@ -0,0 +1,294 @@ +/* linux/drivers/mmc/host/sdhci-s3c.c + * + * Copyright 2008 Openmoko Inc. + * Copyright 2008 Simtec Electronics + * Ben Dooks <ben@simtec.co.uk> + * http://armlinux.simtec.co.uk/ + * + * SDHCI (HSMMC) support for Samsung SoC + * + * 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 <linux/delay.h> +#include <linux/dma-mapping.h> +#include <linux/platform_device.h> +#include <linux/clk.h> +#include <linux/io.h> + +#include <linux/mmc/host.h> + +#include <plat/sdhci.h> + +#include "sdhci.h" + +#define MAX_BUS_CLK (4) + +struct sdhci_s3c { + struct sdhci_host *host; + struct platform_device *pdev; + struct resource *ioarea; + struct s3c_sdhci_platdata *pdata; + + struct clk *clk_io; /* clock for io bus */ + struct clk *clk_bus[MAX_BUS_CLK]; +}; + +static inline struct sdhci_s3c *to_s3c(struct sdhci_host *host) +{ + return sdhci_priv(host); +} + + +static void sdhci_s3c_sel_sclk(struct sdhci_host *host) +{ + struct sdhci_s3c *ourhost = to_s3c(host); + + /* select sclk */ + u32 tmp = readl(host->ioaddr + 0x80); + + if ((tmp & (3 << 4)) == (2 << 4)) + return; + + tmp &= ~(3<<4); + tmp |= (2 << 4); + writel(tmp, host->ioaddr + 0x80); +} + + +static unsigned int sdhci_s3c_get_max_clk(struct sdhci_host *host) +{ + struct sdhci_s3c *ourhost = to_s3c(host); + u32 control2; + unsigned int rate; + int clk; + + /* note, a reset will reset the clock source */ + + sdhci_s3c_sel_sclk(host); + + control2 = readl(host->ioaddr + 0x80); + clk = clk_get_rate(ourhost->clk_bus[(control2 >> 4) & 3]); + + return clk; +} + +static unsigned int sdhci_s3c_get_timeout_clk(struct sdhci_host *host) +{ + return sdhci_s3c_get_max_clk(host) / 1000000; +} + +static void sdhci_s3c_set_ios(struct sdhci_host *host, + struct mmc_ios *ios) +{ + struct sdhci_s3c *ourhost = to_s3c(host); + struct s3c_sdhci_platdata *pdata = ourhost->pdata; + int width; + + sdhci_s3c_sel_sclk(host); + + if (ios->power_mode != MMC_POWER_OFF) { + switch (ios->bus_width) { + case MMC_BUS_WIDTH_4: + width = 4; + break; + case MMC_BUS_WIDTH_1: + width = 1; + break; + default: + BUG(); + } + + if (pdata->cfg_gpio) + pdata->cfg_gpio(ourhost->pdev, width); + } + + if (pdata->cfg_card) + pdata->cfg_card(ourhost->pdev, host->ioaddr, + ios, host->mmc->card); +} + +static struct sdhci_ops sdhci_s3c_ops = { + .get_max_clock = sdhci_s3c_get_max_clk, + .get_timeout_clock = sdhci_s3c_get_timeout_clk, + .set_ios = sdhci_s3c_set_ios, +}; + +static int __devinit sdhci_s3c_probe(struct platform_device *pdev) +{ + struct s3c_sdhci_platdata *pdata = pdev->dev.platform_data; + struct device *dev = &pdev->dev; + struct sdhci_host *host; + struct sdhci_s3c *sc; + struct resource *res; + int ret, irq, ptr, clks; + + if (!pdata) { + dev_err(dev, "no device data specified\n"); + return -ENOENT; + } + + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + dev_err(dev, "no irq specified\n"); + return irq; + } + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) { + dev_err(dev, "no memory specified\n"); + return -ENOENT; + } + + host = sdhci_alloc_host(dev, sizeof(struct sdhci_s3c)); + if (IS_ERR(host)) { + dev_err(dev, "sdhci_alloc_host() failed\n"); + return PTR_ERR(host); + } + + sc = sdhci_priv(host); + + sc->host = host; + sc->pdev = pdev; + sc->pdata = pdata; + + sc->clk_io = clk_get(dev, "hsmmc"); + if (IS_ERR(sc->clk_io)) { + dev_err(dev, "failed to get io clock\n"); + ret = PTR_ERR(sc->clk_io); + goto err_io_clk; + } + + /* enable the local io clock and keep it running for the moment. */ + clk_enable(sc->clk_io); + + for (clks = 0, ptr = 0; ptr < MAX_BUS_CLK; ptr++) { + struct clk *clk; + char *name = pdata->clocks[ptr]; + + if (name == NULL) + continue; + + clk = clk_get(dev, name); + if (IS_ERR(clk)) { + dev_err(dev, "failed to get clock %s\n", name); + continue; + } + + clks++; + sc->clk_bus[ptr] = clk; + clk_enable(clk); + + dev_info(dev, "clock source %d: %s (%ld Hz)\n", + ptr, name, clk_get_rate(clk)); + } + + if (clks == 0) { + dev_err(dev, "failed to find any bus clocks\n"); + ret = -ENOENT; + goto err_no_busclks; + } + + sc->ioarea = request_mem_region(res->start, resource_size(res), + mmc_hostname(host->mmc)); + if (!sc->ioarea) { + dev_err(dev, "failed to reserve register area\n"); + ret = -ENXIO; + goto err_req_regs; + } + + host->ioaddr = ioremap_nocache(res->start, resource_size(res)); + if (!host->ioaddr) { + dev_err(dev, "failed to map registers\n"); + ret = -ENXIO; + goto err_req_regs; + } + + /* Ensure we have minimal gpio selected CMD/CLK/Detect */ + if (pdata->cfg_gpio) + pdata->cfg_gpio(pdev, 0); + + sdhci_s3c_sel_sclk(host); + + host->hw_name = "samsung-hsmmc"; + host->ops = &sdhci_s3c_ops; + host->quirks = 0; + host->irq = irq; + + /* Setup quirks for the controller */ + + /* Currently with ADMA enabled we are getting some length + * interrupts that are not being dealt with, do disable + * ADMA until this is sorted out. */ + host->quirks |= SDHCI_QUIRK_BROKEN_ADMA; + host->quirks |= SDHCI_QUIRK_32BIT_ADMA_SIZE; + + /* It seems we do not get an DATA transfer complete on non-busy + * transfers, not sure if this is a problem with this specific + * SDHCI block, or a missing configuration that needs to be set. */ + host->quirks |= SDHCI_QUIRK_NO_TCIRQ_ON_NOT_BUSY; + + host->quirks |= (SDHCI_QUIRK_32BIT_DMA_ADDR | + SDHCI_QUIRK_32BIT_DMA_SIZE); + + ret = sdhci_add_host(host); + if (ret) { + dev_err(dev, "sdhci_add_host() failed\n"); + goto err_add_host; + } + + return 0; + + err_add_host: + release_resource(sc->ioarea); + kfree(sc->ioarea); + + err_req_regs: + for (ptr = 0; ptr < MAX_BUS_CLK; ptr++) { + clk_disable(sc->clk_bus[ptr]); + clk_put(sc->clk_bus[ptr]); + } + + err_no_busclks: + clk_disable(sc->clk_io); + clk_put(sc->clk_io); + + err_io_clk: + sdhci_free_host(host); + + return ret; +} + +static int __devexit sdhci_s3c_remove(struct platform_device *pdev) +{ + return 0; +} + +static struct platform_driver sdhci_s3c_driver = { + .probe = sdhci_s3c_probe, + .remove = __devexit_p(sdhci_s3c_remove), + .driver = { + .owner = THIS_MODULE, + .name = "s3c-sdhci", + }, +}; + +static int __init sdhci_s3c_init(void) +{ + return platform_driver_register(&sdhci_s3c_driver); +} + +static void __exit sdhci_s3c_exit(void) +{ + platform_driver_unregister(&sdhci_s3c_driver); +} + +module_init(sdhci_s3c_init); +module_exit(sdhci_s3c_exit); + +MODULE_DESCRIPTION("Samsung SDHCI (HSMMC) glue"); +MODULE_AUTHOR("Ben Dooks, <ben@simtec.co.uk>"); +MODULE_LICENSE("GPLv2"); +MODULE_ALIAS("platform:s3c-sdhci"); |