linux/drivers/mmc/host/tmio_mmc.c
Wolfram Sang 576146ea4e mmc: tmio: factor out common parts of the reset routine
Some TMIO variants need specific actions in their reset routine, but
they are all based on a generic reset routine. So, the optional 'reset'
callback will now only take care of the additional stuff and we will
have a generic function around it. Less code, easier to maintain, and
much more readable. Code in tmio_mmc.c is untested but in my TC6387XB
datasheet the SDIO part is reset independently from the SD part, too.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Tested-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/20200820132538.24758-5-wsa+renesas@sang-engineering.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2020-09-07 09:11:31 +02:00

228 lines
5.2 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Driver for the MMC / SD / SDIO cell found in:
*
* TC6393XB TC6391XB TC6387XB T7L66XB ASIC3
*
* Copyright (C) 2017 Renesas Electronics Corporation
* Copyright (C) 2017 Horms Solutions, Simon Horman
* Copyright (C) 2007 Ian Molton
* Copyright (C) 2004 Ian Molton
*/
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/mfd/core.h>
#include <linux/mfd/tmio.h>
#include <linux/mmc/host.h>
#include <linux/module.h>
#include <linux/pagemap.h>
#include <linux/scatterlist.h>
#include "tmio_mmc.h"
/* Registers specific to this variant */
#define CTL_SDIO_REGS 0x100
#define CTL_CLK_AND_WAIT_CTL 0x138
#define CTL_RESET_SDIO 0x1e0
static void tmio_mmc_clk_start(struct tmio_mmc_host *host)
{
sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, CLK_CTL_SCLKEN |
sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
usleep_range(10000, 11000);
sd_ctrl_write16(host, CTL_CLK_AND_WAIT_CTL, 0x0100);
usleep_range(10000, 11000);
}
static void tmio_mmc_clk_stop(struct tmio_mmc_host *host)
{
sd_ctrl_write16(host, CTL_CLK_AND_WAIT_CTL, 0x0000);
usleep_range(10000, 11000);
sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, ~CLK_CTL_SCLKEN &
sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
usleep_range(10000, 11000);
}
static void tmio_mmc_set_clock(struct tmio_mmc_host *host,
unsigned int new_clock)
{
unsigned int divisor;
u32 clk = 0;
int clk_sel;
if (new_clock == 0) {
tmio_mmc_clk_stop(host);
return;
}
divisor = host->pdata->hclk / new_clock;
/* bit7 set: 1/512, ... bit0 set: 1/4, all bits clear: 1/2 */
clk_sel = (divisor <= 1);
clk = clk_sel ? 0 : (roundup_pow_of_two(divisor) >> 2);
host->pdata->set_clk_div(host->pdev, clk_sel);
sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, ~CLK_CTL_SCLKEN &
sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, clk & CLK_CTL_DIV_MASK);
usleep_range(10000, 11000);
tmio_mmc_clk_start(host);
}
static void tmio_mmc_reset(struct tmio_mmc_host *host)
{
sd_ctrl_write16(host, CTL_RESET_SDIO, 0x0000);
usleep_range(10000, 11000);
sd_ctrl_write16(host, CTL_RESET_SDIO, 0x0001);
usleep_range(10000, 11000);
}
#ifdef CONFIG_PM_SLEEP
static int tmio_mmc_suspend(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
const struct mfd_cell *cell = mfd_get_cell(pdev);
int ret;
ret = pm_runtime_force_suspend(dev);
/* Tell MFD core it can disable us now.*/
if (!ret && cell->disable)
cell->disable(pdev);
return ret;
}
static int tmio_mmc_resume(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
const struct mfd_cell *cell = mfd_get_cell(pdev);
int ret = 0;
/* Tell the MFD core we are ready to be enabled */
if (cell->resume)
ret = cell->resume(pdev);
if (!ret)
ret = pm_runtime_force_resume(dev);
return ret;
}
#endif
static int tmio_mmc_probe(struct platform_device *pdev)
{
const struct mfd_cell *cell = mfd_get_cell(pdev);
struct tmio_mmc_data *pdata;
struct tmio_mmc_host *host;
struct resource *res;
int ret = -EINVAL, irq;
if (pdev->num_resources != 2)
goto out;
pdata = pdev->dev.platform_data;
if (!pdata || !pdata->hclk)
goto out;
irq = platform_get_irq(pdev, 0);
if (irq < 0) {
ret = irq;
goto out;
}
/* Tell the MFD core we are ready to be enabled */
if (cell->enable) {
ret = cell->enable(pdev);
if (ret)
goto out;
}
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res) {
ret = -EINVAL;
goto cell_disable;
}
host = tmio_mmc_host_alloc(pdev, pdata);
if (IS_ERR(host)) {
ret = PTR_ERR(host);
goto cell_disable;
}
/* SD control register space size is 0x200, 0x400 for bus_shift=1 */
host->bus_shift = resource_size(res) >> 10;
host->set_clock = tmio_mmc_set_clock;
host->reset = tmio_mmc_reset;
host->mmc->f_max = pdata->hclk;
host->mmc->f_min = pdata->hclk / 512;
ret = tmio_mmc_host_probe(host);
if (ret)
goto host_free;
ret = devm_request_irq(&pdev->dev, irq, tmio_mmc_irq,
IRQF_TRIGGER_FALLING,
dev_name(&pdev->dev), host);
if (ret)
goto host_remove;
pr_info("%s at 0x%08lx irq %d\n", mmc_hostname(host->mmc),
(unsigned long)host->ctl, irq);
return 0;
host_remove:
tmio_mmc_host_remove(host);
host_free:
tmio_mmc_host_free(host);
cell_disable:
if (cell->disable)
cell->disable(pdev);
out:
return ret;
}
static int tmio_mmc_remove(struct platform_device *pdev)
{
const struct mfd_cell *cell = mfd_get_cell(pdev);
struct tmio_mmc_host *host = platform_get_drvdata(pdev);
tmio_mmc_host_remove(host);
if (cell->disable)
cell->disable(pdev);
return 0;
}
/* ------------------- device registration ----------------------- */
static const struct dev_pm_ops tmio_mmc_dev_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(tmio_mmc_suspend, tmio_mmc_resume)
SET_RUNTIME_PM_OPS(tmio_mmc_host_runtime_suspend,
tmio_mmc_host_runtime_resume, NULL)
};
static struct platform_driver tmio_mmc_driver = {
.driver = {
.name = "tmio-mmc",
.pm = &tmio_mmc_dev_pm_ops,
},
.probe = tmio_mmc_probe,
.remove = tmio_mmc_remove,
};
module_platform_driver(tmio_mmc_driver);
MODULE_DESCRIPTION("Toshiba TMIO SD/MMC driver");
MODULE_AUTHOR("Ian Molton <spyro@f2s.com>");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:tmio-mmc");