diff options
Diffstat (limited to 'drivers/power/avs')
| -rw-r--r-- | drivers/power/avs/Kconfig | 8 | ||||
| -rw-r--r-- | drivers/power/avs/Makefile | 1 | ||||
| -rw-r--r-- | drivers/power/avs/rockchip-io-domain.c | 351 |
3 files changed, 360 insertions, 0 deletions
diff --git a/drivers/power/avs/Kconfig b/drivers/power/avs/Kconfig index 2a1008b61121..7f3d389bd601 100644 --- a/drivers/power/avs/Kconfig +++ b/drivers/power/avs/Kconfig @@ -10,3 +10,11 @@ menuconfig POWER_AVS AVS is also called SmartReflex on OMAP devices. Say Y here to enable Adaptive Voltage Scaling class support. + +config ROCKCHIP_IODOMAIN + tristate "Rockchip IO domain support" + depends on ARCH_ROCKCHIP && OF + help + Say y here to enable support io domains on Rockchip SoCs. It is + necessary for the io domain setting of the SoC to match the + voltage supplied by the regulators. diff --git a/drivers/power/avs/Makefile b/drivers/power/avs/Makefile index 0843386a6c19..ba4c7bc69225 100644 --- a/drivers/power/avs/Makefile +++ b/drivers/power/avs/Makefile @@ -1 +1,2 @@ obj-$(CONFIG_POWER_AVS_OMAP) += smartreflex.o +obj-$(CONFIG_ROCKCHIP_IODOMAIN) += rockchip-io-domain.o diff --git a/drivers/power/avs/rockchip-io-domain.c b/drivers/power/avs/rockchip-io-domain.c new file mode 100644 index 000000000000..3ae35d0590d2 --- /dev/null +++ b/drivers/power/avs/rockchip-io-domain.c @@ -0,0 +1,351 @@ +/* + * 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 + +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"); +} + +/* + * 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 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 + }, + { /* sentinel */ }, +}; + +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"); |