mmc: sh_mobile_sdhi: Add UHS-I mode support

Implement voltage switch, supporting modes up to SDR-50.

Based on work by Shinobu Uehara, Rob Taylor, William Towle and Ian Molton.

Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This commit is contained in:
Wolfram Sang 2016-04-01 17:44:37 +02:00 committed by Ulf Hansson
parent 93b6911ac1
commit 057a4592e6
2 changed files with 55 additions and 0 deletions

View File

@ -26,3 +26,6 @@ Required properties:
Optional properties:
- toshiba,mmc-wrprotect-disable: write-protect detection is unavailable
- pinctrl-names: should be "default", "state_uhs"
- pinctrl-0: should contain default/high speed pin ctrl
- pinctrl-1: should contain uhs mode pin ctrl

View File

@ -32,6 +32,9 @@
#include <linux/mfd/tmio.h>
#include <linux/sh_dma.h>
#include <linux/delay.h>
#include <linux/pinctrl/consumer.h>
#include <linux/pinctrl/pinctrl-state.h>
#include <linux/regulator/consumer.h>
#include "tmio_mmc.h"
@ -97,6 +100,8 @@ struct sh_mobile_sdhi {
struct clk *clk;
struct tmio_mmc_data mmc_data;
struct tmio_mmc_dma dma_priv;
struct pinctrl *pinctrl;
struct pinctrl_state *pins_default, *pins_uhs;
};
static void sh_mobile_sdhi_sdbuf_width(struct tmio_mmc_host *host, int width)
@ -205,6 +210,44 @@ static void sh_mobile_sdhi_clk_disable(struct tmio_mmc_host *host)
clk_disable_unprepare(priv->clk);
}
static int sh_mobile_sdhi_start_signal_voltage_switch(struct mmc_host *mmc,
struct mmc_ios *ios)
{
struct tmio_mmc_host *host = mmc_priv(mmc);
struct sh_mobile_sdhi *priv = host_to_priv(host);
struct pinctrl_state *pin_state;
int ret;
switch (ios->signal_voltage) {
case MMC_SIGNAL_VOLTAGE_330:
pin_state = priv->pins_default;
break;
case MMC_SIGNAL_VOLTAGE_180:
pin_state = priv->pins_uhs;
break;
default:
return -EINVAL;
}
/*
* If anything is missing, assume signal voltage is fixed at
* 3.3V and succeed/fail accordingly.
*/
if (IS_ERR(priv->pinctrl) || IS_ERR(pin_state))
return ios->signal_voltage ==
MMC_SIGNAL_VOLTAGE_330 ? 0 : -EINVAL;
ret = mmc_regulator_set_vqmmc(host->mmc, ios);
if (ret)
return ret;
ret = pinctrl_select_state(priv->pinctrl, pin_state);
if (ret)
return ret;
return 0;
}
static int sh_mobile_sdhi_wait_idle(struct tmio_mmc_host *host)
{
int timeout = 1000;
@ -296,6 +339,14 @@ static int sh_mobile_sdhi_probe(struct platform_device *pdev)
goto eprobe;
}
priv->pinctrl = devm_pinctrl_get(&pdev->dev);
if (!IS_ERR(priv->pinctrl)) {
priv->pins_default = pinctrl_lookup_state(priv->pinctrl,
PINCTRL_STATE_DEFAULT);
priv->pins_uhs = pinctrl_lookup_state(priv->pinctrl,
"state_uhs");
}
host = tmio_mmc_host_alloc(pdev);
if (!host) {
ret = -ENOMEM;
@ -319,6 +370,7 @@ static int sh_mobile_sdhi_probe(struct platform_device *pdev)
host->clk_update = sh_mobile_sdhi_clk_update;
host->clk_disable = sh_mobile_sdhi_clk_disable;
host->multi_io_quirk = sh_mobile_sdhi_multi_io_quirk;
host->start_signal_voltage_switch = sh_mobile_sdhi_start_signal_voltage_switch;
/* Orginally registers were 16 bit apart, could be 32 or 64 nowadays */
if (!host->bus_shift && resource_size(res) > 0x100) /* old way to determine the shift */