linux/drivers/mmc/host/dw_mmc-socfpga.c

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/*
* Altera SoCFPGA Specific Extensions for Synopsys DW Multimedia Card Interface
* driver
*
* Copyright (C) 2012, Samsung Electronics Co., Ltd.
* Copyright (C) 2013 Altera 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; either version 2 of the License, or
* (at your option) any later version.
*
* Taken from dw_mmc-exynos.c
*/
#include <linux/clk.h>
#include <linux/mfd/syscon.h>
#include <linux/mmc/host.h>
#include <linux/mmc/dw_mmc.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include "dw_mmc.h"
#include "dw_mmc-pltfm.h"
#define SYSMGR_SDMMCGRP_CTRL_OFFSET 0x108
#define DRV_CLK_PHASE_SHIFT_SEL_MASK 0x7
#define SYSMGR_SDMMC_CTRL_SET(smplsel, drvsel) \
((((smplsel) & 0x7) << 3) | (((drvsel) & 0x7) << 0))
/* SOCFPGA implementation specific driver private data */
struct dw_mci_socfpga_priv_data {
u8 ciu_div; /* card interface unit divisor */
u32 hs_timing; /* bitmask for CIU clock phase shift */
struct regmap *sysreg; /* regmap for system manager register */
};
static int dw_mci_socfpga_priv_init(struct dw_mci *host)
{
return 0;
}
static int dw_mci_socfpga_setup_clock(struct dw_mci *host)
{
struct dw_mci_socfpga_priv_data *priv = host->priv;
clk_disable_unprepare(host->ciu_clk);
regmap_write(priv->sysreg, SYSMGR_SDMMCGRP_CTRL_OFFSET,
priv->hs_timing);
clk_prepare_enable(host->ciu_clk);
host->bus_hz /= (priv->ciu_div + 1);
return 0;
}
static void dw_mci_socfpga_prepare_command(struct dw_mci *host, u32 *cmdr)
{
struct dw_mci_socfpga_priv_data *priv = host->priv;
if (priv->hs_timing & DRV_CLK_PHASE_SHIFT_SEL_MASK)
*cmdr |= SDMMC_CMD_USE_HOLD_REG;
}
static int dw_mci_socfpga_parse_dt(struct dw_mci *host)
{
struct dw_mci_socfpga_priv_data *priv;
struct device_node *np = host->dev->of_node;
u32 timing[2];
u32 div = 0;
int ret;
priv = devm_kzalloc(host->dev, sizeof(*priv), GFP_KERNEL);
if (!priv) {
dev_err(host->dev, "mem alloc failed for private data\n");
return -ENOMEM;
}
priv->sysreg = syscon_regmap_lookup_by_compatible("altr,sys-mgr");
if (IS_ERR(priv->sysreg)) {
dev_err(host->dev, "regmap for altr,sys-mgr lookup failed.\n");
return PTR_ERR(priv->sysreg);
}
ret = of_property_read_u32(np, "altr,dw-mshc-ciu-div", &div);
if (ret)
dev_info(host->dev, "No dw-mshc-ciu-div specified, assuming 1");
priv->ciu_div = div;
ret = of_property_read_u32_array(np,
"altr,dw-mshc-sdr-timing", timing, 2);
if (ret)
return ret;
priv->hs_timing = SYSMGR_SDMMC_CTRL_SET(timing[0], timing[1]);
host->priv = priv;
return 0;
}
static const struct dw_mci_drv_data socfpga_drv_data = {
.init = dw_mci_socfpga_priv_init,
.setup_clock = dw_mci_socfpga_setup_clock,
.prepare_command = dw_mci_socfpga_prepare_command,
.parse_dt = dw_mci_socfpga_parse_dt,
};
static const struct of_device_id dw_mci_socfpga_match[] = {
{ .compatible = "altr,socfpga-dw-mshc",
.data = &socfpga_drv_data, },
{},
};
MODULE_DEVICE_TABLE(of, dw_mci_socfpga_match);
static int dw_mci_socfpga_probe(struct platform_device *pdev)
{
const struct dw_mci_drv_data *drv_data;
const struct of_device_id *match;
match = of_match_node(dw_mci_socfpga_match, pdev->dev.of_node);
drv_data = match->data;
return dw_mci_pltfm_register(pdev, drv_data);
}
static struct platform_driver dw_mci_socfpga_pltfm_driver = {
.probe = dw_mci_socfpga_probe,
.remove = __exit_p(dw_mci_pltfm_remove),
.driver = {
.name = "dwmmc_socfpga",
.of_match_table = dw_mci_socfpga_match,
.pm = &dw_mci_pltfm_pmops,
},
};
module_platform_driver(dw_mci_socfpga_pltfm_driver);
MODULE_DESCRIPTION("Altera SOCFPGA Specific DW-MSHC Driver Extension");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:dwmmc-socfpga");