- 根目录:
- drivers
- power
- avs
- rockchip-io-domain.c
/*
* Rockchip IO Voltage Domain driver
*
* Copyright 2014 MundoReader S.L.
* Copyright 2014 Google, Inc.
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* 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.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/err.h>
#include <linux/mfd/syscon.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/regulator/consumer.h>
#define MAX_SUPPLIES 16
/*
* The max voltage for 1.8V and 3.3V come from the Rockchip datasheet under
* "Recommended Operating Conditions" for "Digital GPIO". When the typical
* is 3.3V the max is 3.6V. When the typical is 1.8V the max is 1.98V.
*
* They are used like this:
* - If the voltage on a rail is above the "1.8" voltage (1.98V) we'll tell the
* SoC we're at 3.3.
* - If the voltage on a rail is above the "3.3" voltage (3.6V) we'll consider
* that to be an error.
*/
#define MAX_VOLTAGE_1_8 1980000
#define MAX_VOLTAGE_3_3 3600000
#define RK3288_SOC_CON2 0x24c
#define RK3288_SOC_CON2_FLASH0 BIT(7)
#define RK3288_SOC_FLASH_SUPPLY_NUM 2
#define RK3368_SOC_CON15 0x43c
#define RK3368_SOC_CON15_FLASH0 BIT(14)
#define RK3368_SOC_FLASH_SUPPLY_NUM 2
struct rockchip_iodomain;
/**
* @supplies: voltage settings matching the register bits.
*/
struct rockchip_iodomain_soc_data {
int grf_offset;
const char *supply_names[MAX_SUPPLIES];
void (*init)(struct rockchip_iodomain *iod);
};
struct rockchip_iodomain_supply {
struct rockchip_iodomain *iod;
struct regulator *reg;
struct notifier_block nb;
int idx;
};
struct rockchip_iodomain {
struct device *dev;
struct regmap *grf;
struct rockchip_iodomain_soc_data *soc_data;
struct rockchip_iodomain_supply supplies[MAX_SUPPLIES];
};
static int rockchip_iodomain_write(struct rockchip_iodomain_supply *supply,
int uV)
{
struct rockchip_iodomain *iod = supply->iod;
u32 val;
int ret;
/* set value bit */
val = (uV > MAX_VOLTAGE_1_8) ? 0 : 1;
val <<= supply->idx;
/* apply hiword-mask */
val |= (BIT(supply->idx) << 16);
ret = regmap_write(iod->grf, iod->soc_data->grf_offset, val);
if (ret)
dev_err(iod->dev, "Couldn't write to GRF\n");
return ret;
}
static int rockchip_iodomain_notify(struct notifier_block *nb,
unsigned long event,
void *data)
{
struct rockchip_iodomain_supply *supply =
container_of(nb, struct rockchip_iodomain_supply, nb);
int uV;
int ret;
/*
* According to Rockchip it's important to keep the SoC IO domain
* higher than (or equal to) the external voltage. That means we need
* to change it before external voltage changes happen in the case
* of an increase.
*
* Note that in the "pre" change we pick the max possible voltage that
* the regulator might end up at (the client requests a range and we
* don't know for certain the exact voltage). Right now we rely on the
* slop in MAX_VOLTAGE_1_8 and MAX_VOLTAGE_3_3 to save us if clients
* request something like a max of 3.6V when they really want 3.3V.
* We could attempt to come up with better rules if this fails.
*/
if (event & REGULATOR_EVENT_PRE_VOLTAGE_CHANGE) {
struct pre_voltage_change_data *pvc_data = data;
uV = max_t(unsigned long, pvc_data->old_uV, pvc_data->max_uV);
} else if (event & (REGULATOR_EVENT_VOLTAGE_CHANGE |
REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE)) {
uV = (unsigned long)data;
} else {
return NOTIFY_OK;
}
dev_dbg(supply->iod->dev, "Setting to %d\n", uV);
if (uV > MAX_VOLTAGE_3_3) {
dev_err(supply->iod->dev, "Voltage too high: %d\n", uV);
if (event == REGULATOR_EVENT_PRE_VOLTAGE_CHANGE)
return NOTIFY_BAD;
}
ret = rockchip_iodomain_write(supply, uV);
if (ret && event == REGULATOR_EVENT_PRE_VOLTAGE_CHANGE)
return NOTIFY_BAD;
dev_info(supply->iod->dev, "Setting to %d done\n", uV);
return NOTIFY_OK;
}
static void rk3288_iodomain_init(struct rockchip_iodomain *iod)
{
int ret;
u32 val;
/* if no flash supply we should leave things alone */
if (!iod->supplies[RK3288_SOC_FLASH_SUPPLY_NUM].reg)
return;
/*
* set flash0 iodomain to also use this framework
* instead of a special gpio.
*/
val = RK3288_SOC_CON2_FLASH0 | (RK3288_SOC_CON2_FLASH0 << 16);
ret = regmap_write(iod->grf, RK3288_SOC_CON2, val);
if (ret < 0)
dev_warn(iod->dev, "couldn't update flash0 ctrl\n");
}
static void rk3368_iodomain_init(struct rockchip_iodomain *iod)
{
int ret;
u32 val;
/* if no flash supply we should leave things alone */
if (!iod->supplies[RK3368_SOC_FLASH_SUPPLY_NUM].reg)
return;
/*
* set flash0 iodomain to also use this framework
* instead of a special gpio.
*/
val = RK3368_SOC_CON15_FLASH0 | (RK3368_SOC_CON15_FLASH0 << 16);
ret = regmap_write(iod->grf, RK3368_SOC_CON15, val);
if (ret < 0)
dev_warn(iod->dev, "couldn't update flash0 ctrl\n");
}
/*
* On the rk3188 the io-domains are handled by a shared register with the
* lower 8 bits being still being continuing drive-strength settings.
*/
static const struct rockchip_iodomain_soc_data soc_data_rk3188 = {
.grf_offset = 0x104,
.supply_names = {
NULL,
NULL,
NULL,
NULL,
NULL,
NULL,
NULL,
NULL,
"ap0",
"ap1",
"cif",
"flash",
"vccio0",
"vccio1",
"lcdc0",
"lcdc1",
},
};
static const struct rockchip_iodomain_soc_data soc_data_rk3288 = {
.grf_offset = 0x380,
.supply_names = {
"lcdc", /* LCDC_VDD */
"dvp", /* DVPIO_VDD */
"flash0", /* FLASH0_VDD (emmc) */
"flash1", /* FLASH1_VDD (sdio1) */
"wifi", /* APIO3_VDD (sdio0) */
"bb", /* APIO5_VDD */
"audio", /* APIO4_VDD */
"sdcard", /* SDMMC0_VDD (sdmmc) */
"gpio30", /* APIO1_VDD */
"gpio1830", /* APIO2_VDD */
},
.init = rk3288_iodomain_init,
};
static const struct rockchip_iodomain_soc_data soc_data_rk3368 = {
.grf_offset = 0x900,
.supply_names = {
NULL, /* reserved */
"dvp", /* DVPIO_VDD */
"flash0", /* FLASH0_VDD (emmc) */
"wifi", /* APIO2_VDD (sdio0) */
NULL,
"audio", /* APIO3_VDD */
"sdcard", /* SDMMC0_VDD (sdmmc) */
"gpio30", /* APIO1_VDD */
"gpio1830", /* APIO4_VDD (gpujtag) */
},
.init = rk3368_iodomain_init,
};
static const struct rockchip_iodomain_soc_data soc_data_rk3368_pmu = {
.grf_offset = 0x100,
.supply_names = {
NULL,
NULL,
NULL,
NULL,
"pmu", /*PMU IO domain*/
"vop", /*LCDC IO domain*/
},
};
static const struct of_device_id rockchip_iodomain_match[] = {
{
.compatible = "rockchip,rk3188-io-voltage-domain",
.data = (void *)&soc_data_rk3188
},
{
.compatible = "rockchip,rk3288-io-voltage-domain",
.data = (void *)&soc_data_rk3288
},
{
.compatible = "rockchip,rk3368-io-voltage-domain",
.data = (void *)&soc_data_rk3368
},
{
.compatible = "rockchip,rk3368-pmu-io-voltage-domain",
.data = (void *)&soc_data_rk3368_pmu
},
{ /* sentinel */ },
};
MODULE_DEVICE_TABLE(of, rockchip_iodomain_match);
static int rockchip_iodomain_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
const struct of_device_id *match;
struct rockchip_iodomain *iod;
int i, ret = 0;
if (!np)
return -ENODEV;
iod = devm_kzalloc(&pdev->dev, sizeof(*iod), GFP_KERNEL);
if (!iod)
return -ENOMEM;
iod->dev = &pdev->dev;
platform_set_drvdata(pdev, iod);
match = of_match_node(rockchip_iodomain_match, np);
iod->soc_data = (struct rockchip_iodomain_soc_data *)match->data;
iod->grf = syscon_regmap_lookup_by_phandle(np, "rockchip,grf");
if (IS_ERR(iod->grf)) {
dev_err(&pdev->dev, "couldn't find grf regmap\n");
return PTR_ERR(iod->grf);
}
for (i = 0; i < MAX_SUPPLIES; i++) {
const char *supply_name = iod->soc_data->supply_names[i];
struct rockchip_iodomain_supply *supply = &iod->supplies[i];
struct regulator *reg;
int uV;
if (!supply_name)
continue;
reg = devm_regulator_get_optional(iod->dev, supply_name);
if (IS_ERR(reg)) {
ret = PTR_ERR(reg);
/* If a supply wasn't specified, that's OK */
if (ret == -ENODEV)
continue;
else if (ret != -EPROBE_DEFER)
dev_err(iod->dev, "couldn't get regulator %s\n",
supply_name);
goto unreg_notify;
}
/* set initial correct value */
uV = regulator_get_voltage(reg);
/* must be a regulator we can get the voltage of */
if (uV < 0) {
dev_err(iod->dev, "Can't determine voltage: %s\n",
supply_name);
goto unreg_notify;
}
if (uV > MAX_VOLTAGE_3_3) {
dev_crit(iod->dev,
"%d uV is too high. May damage SoC!\n",
uV);
ret = -EINVAL;
goto unreg_notify;
}
/* setup our supply */
supply->idx = i;
supply->iod = iod;
supply->reg = reg;
supply->nb.notifier_call = rockchip_iodomain_notify;
ret = rockchip_iodomain_write(supply, uV);
if (ret) {
supply->reg = NULL;
goto unreg_notify;
}
/* register regulator notifier */
ret = regulator_register_notifier(reg, &supply->nb);
if (ret) {
dev_err(&pdev->dev,
"regulator notifier request failed\n");
supply->reg = NULL;
goto unreg_notify;
}
}
if (iod->soc_data->init)
iod->soc_data->init(iod);
return 0;
unreg_notify:
for (i = MAX_SUPPLIES - 1; i >= 0; i--) {
struct rockchip_iodomain_supply *io_supply = &iod->supplies[i];
if (io_supply->reg)
regulator_unregister_notifier(io_supply->reg,
&io_supply->nb);
}
return ret;
}
static int rockchip_iodomain_remove(struct platform_device *pdev)
{
struct rockchip_iodomain *iod = platform_get_drvdata(pdev);
int i;
for (i = MAX_SUPPLIES - 1; i >= 0; i--) {
struct rockchip_iodomain_supply *io_supply = &iod->supplies[i];
if (io_supply->reg)
regulator_unregister_notifier(io_supply->reg,
&io_supply->nb);
}
return 0;
}
static struct platform_driver rockchip_iodomain_driver = {
.probe = rockchip_iodomain_probe,
.remove = rockchip_iodomain_remove,
.driver = {
.name = "rockchip-iodomain",
.of_match_table = rockchip_iodomain_match,
},
};
module_platform_driver(rockchip_iodomain_driver);
MODULE_DESCRIPTION("Rockchip IO-domain driver");
MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>");
MODULE_AUTHOR("Doug Anderson <dianders@chromium.org>");
MODULE_LICENSE("GPL v2");