diff options
Diffstat (limited to 'arch/arm/mach-omap2/msdi.c')
| -rw-r--r-- | arch/arm/mach-omap2/msdi.c | 159 |
1 files changed, 159 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/msdi.c b/arch/arm/mach-omap2/msdi.c new file mode 100644 index 00000000..c52d8b4a --- /dev/null +++ b/arch/arm/mach-omap2/msdi.c @@ -0,0 +1,159 @@ +/* + * MSDI IP block reset + * + * Copyright (C) 2012 Texas Instruments, Inc. + * Paul Walmsley + * + * 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. + * + * 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. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA + * 02110-1301 USA + * + * XXX What about pad muxing? + */ + +#include <linux/kernel.h> +#include <linux/err.h> +#include <linux/platform_data/gpio-omap.h> + +#include "prm.h" +#include "common.h" +#include "control.h" +#include "omap_hwmod.h" +#include "omap_device.h" +#include "mux.h" +#include "mmc.h" + +/* + * MSDI_CON_OFFSET: offset in bytes of the MSDI IP block's CON register + * from the IP block's base address + */ +#define MSDI_CON_OFFSET 0x0c + +/* Register bitfields in the CON register */ +#define MSDI_CON_POW_MASK BIT(11) +#define MSDI_CON_CLKD_MASK (0x3f << 0) +#define MSDI_CON_CLKD_SHIFT 0 + +/* MSDI_TARGET_RESET_CLKD: clock divisor to use throughout the reset */ +#define MSDI_TARGET_RESET_CLKD 0x3ff + +/** + * omap_msdi_reset - reset the MSDI IP block + * @oh: struct omap_hwmod * + * + * The MSDI IP block on OMAP2420 has to have both the POW and CLKD + * fields set inside its CON register for a reset to complete + * successfully. This is not documented in the TRM. For CLKD, we use + * the value that results in the lowest possible clock rate, to attempt + * to avoid disturbing any cards. + */ +int omap_msdi_reset(struct omap_hwmod *oh) +{ + u16 v = 0; + int c = 0; + + /* Write to the SOFTRESET bit */ + omap_hwmod_softreset(oh); + + /* Enable the MSDI core and internal clock */ + v |= MSDI_CON_POW_MASK; + v |= MSDI_TARGET_RESET_CLKD << MSDI_CON_CLKD_SHIFT; + omap_hwmod_write(v, oh, MSDI_CON_OFFSET); + + /* Poll on RESETDONE bit */ + omap_test_timeout((omap_hwmod_read(oh, oh->class->sysc->syss_offs) + & SYSS_RESETDONE_MASK), + MAX_MODULE_SOFTRESET_WAIT, c); + + if (c == MAX_MODULE_SOFTRESET_WAIT) + pr_warning("%s: %s: softreset failed (waited %d usec)\n", + __func__, oh->name, MAX_MODULE_SOFTRESET_WAIT); + else + pr_debug("%s: %s: softreset in %d usec\n", __func__, + oh->name, c); + + /* Disable the MSDI internal clock */ + v &= ~MSDI_CON_CLKD_MASK; + omap_hwmod_write(v, oh, MSDI_CON_OFFSET); + + return 0; +} + +#if defined(CONFIG_MMC_OMAP) || defined(CONFIG_MMC_OMAP_MODULE) + +static inline void omap242x_mmc_mux(struct omap_mmc_platform_data + *mmc_controller) +{ + if ((mmc_controller->slots[0].switch_pin > 0) && \ + (mmc_controller->slots[0].switch_pin < OMAP_MAX_GPIO_LINES)) + omap_mux_init_gpio(mmc_controller->slots[0].switch_pin, + OMAP_PIN_INPUT_PULLUP); + if ((mmc_controller->slots[0].gpio_wp > 0) && \ + (mmc_controller->slots[0].gpio_wp < OMAP_MAX_GPIO_LINES)) + omap_mux_init_gpio(mmc_controller->slots[0].gpio_wp, + OMAP_PIN_INPUT_PULLUP); + + omap_mux_init_signal("sdmmc_cmd", 0); + omap_mux_init_signal("sdmmc_clki", 0); + omap_mux_init_signal("sdmmc_clko", 0); + omap_mux_init_signal("sdmmc_dat0", 0); + omap_mux_init_signal("sdmmc_dat_dir0", 0); + omap_mux_init_signal("sdmmc_cmd_dir", 0); + if (mmc_controller->slots[0].caps & MMC_CAP_4_BIT_DATA) { + omap_mux_init_signal("sdmmc_dat1", 0); + omap_mux_init_signal("sdmmc_dat2", 0); + omap_mux_init_signal("sdmmc_dat3", 0); + omap_mux_init_signal("sdmmc_dat_dir1", 0); + omap_mux_init_signal("sdmmc_dat_dir2", 0); + omap_mux_init_signal("sdmmc_dat_dir3", 0); + } + + /* + * Use internal loop-back in MMC/SDIO Module Input Clock + * selection + */ + if (mmc_controller->slots[0].internal_clock) { + u32 v = omap_ctrl_readl(OMAP2_CONTROL_DEVCONF0); + v |= (1 << 24); + omap_ctrl_writel(v, OMAP2_CONTROL_DEVCONF0); + } +} + +void __init omap242x_init_mmc(struct omap_mmc_platform_data **mmc_data) +{ + struct platform_device *pdev; + struct omap_hwmod *oh; + int id = 0; + char *oh_name = "msdi1"; + char *dev_name = "mmci-omap"; + + if (!mmc_data[0]) { + pr_err("%s fails: Incomplete platform data\n", __func__); + return; + } + + omap242x_mmc_mux(mmc_data[0]); + + oh = omap_hwmod_lookup(oh_name); + if (!oh) { + pr_err("Could not look up %s\n", oh_name); + return; + } + pdev = omap_device_build(dev_name, id, oh, mmc_data[0], + sizeof(struct omap_mmc_platform_data)); + if (IS_ERR(pdev)) + WARN(1, "Can'd build omap_device for %s:%s.\n", + dev_name, oh->name); +} + +#endif |