On 09/11/16 13:06, Laxman Dewangan wrote:
> NVIDIA Tegra124 and later SoCs support the multi-voltage level and
> low power state of some of its IO pads. The IO pads can work in
> the voltage of the 1.8V and 3.3V of IO voltage from IO power rail
> sources. When IO interfaces are not used then IO pads can be
> configure in low power state to reduce the power consumption from
> that IO pads.
>
> On Tegra124, the voltage level of IO power rail source is auto
> detected by hardware(SoC) and hence it is only require to configure
> in low power mode if IO pads are not used.
>
> On T210 onwards, the auto-detection of voltage level from IO power
> rail is removed from SoC and hence SW need to configure the PMC
> register explicitly to set proper voltage in IO pads based on
> IO rail power source voltage.
>
> This driver adds the IO pad driver to configure the power state and
> IO pad voltage based on the usage and power tree via pincontrol
> framework. The configuration can be static and dynamic.
>
> Signed-off-by: Laxman Dewangan <ldewangan@xxxxxxxxxx>
>
> ---
> Changes from V1:
> - Dropped the custom properties to set pad voltage and use regulator.
> - Added support for regulator to get vottage in boot and configure IO
> pad voltage.
> - Add support for callback to handle regulator notification and configure
> IO pad voltage based on voltage change.
> ---
> drivers/pinctrl/tegra/Kconfig | 12 +
> drivers/pinctrl/tegra/Makefile | 1 +
> drivers/pinctrl/tegra/pinctrl-tegra-io-pad.c | 488 +++++++++++++++++++++++++++
> 3 files changed, 501 insertions(+)
> create mode 100644 drivers/pinctrl/tegra/pinctrl-tegra-io-pad.c
>
> diff --git a/drivers/pinctrl/tegra/Kconfig b/drivers/pinctrl/tegra/Kconfig
> index 24e20cc..6004e5c 100644
> --- a/drivers/pinctrl/tegra/Kconfig
> +++ b/drivers/pinctrl/tegra/Kconfig
> @@ -23,6 +23,18 @@ config PINCTRL_TEGRA210
> bool
> select PINCTRL_TEGRA
>
> +config PINCTRL_TEGRA_IO_PAD
> + bool "Tegra IO pad Control Driver"
> + depends on ARCH_TEGRA && REGULATOR
> + select PINCONF
> + select PINMUX
> + help
> + NVIDIA Tegra124/210 SoC has IO pads which supports multi-voltage
> + level of interfacing and deep power down mode of IO pads. The
> + voltage of IO pads are SW configurable based on IO rail of that
> + pads on T210. This driver provides the interface to change IO pad
> + voltage and power state via pincontrol interface.
> +
> config PINCTRL_TEGRA_XUSB
> def_bool y if ARCH_TEGRA
> select GENERIC_PHY
> diff --git a/drivers/pinctrl/tegra/Makefile b/drivers/pinctrl/tegra/Makefile
> index d9ea2be..3ebaaa2 100644
> --- a/drivers/pinctrl/tegra/Makefile
> +++ b/drivers/pinctrl/tegra/Makefile
> @@ -4,4 +4,5 @@ obj-$(CONFIG_PINCTRL_TEGRA30) += pinctrl-tegra30.o
> obj-$(CONFIG_PINCTRL_TEGRA114) += pinctrl-tegra114.o
> obj-$(CONFIG_PINCTRL_TEGRA124) += pinctrl-tegra124.o
> obj-$(CONFIG_PINCTRL_TEGRA210) += pinctrl-tegra210.o
> +obj-$(CONFIG_PINCTRL_TEGRA_IO_PAD) += pinctrl-tegra-io-pad.o
> obj-$(CONFIG_PINCTRL_TEGRA_XUSB) += pinctrl-tegra-xusb.o
> diff --git a/drivers/pinctrl/tegra/pinctrl-tegra-io-pad.c b/drivers/pinctrl/tegra/pinctrl-tegra-io-pad.c
> new file mode 100644
> index 0000000..f5cf0d0
> --- /dev/null
> +++ b/drivers/pinctrl/tegra/pinctrl-tegra-io-pad.c
> @@ -0,0 +1,488 @@
> +/*
> + * pinctrl-tegra-io-pad: IO PAD driver for configuration of IO rail and deep
> + * Power Down mode via pinctrl framework.
> + *
> + * Copyright (C) 2016 NVIDIA CORPORATION. All rights reserved.
> + *
> + * Author: Laxman Dewangan <ldewangan@xxxxxxxxxx>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/pinctrl/pinctrl.h>
> +#include <linux/pinctrl/pinconf-generic.h>
> +#include <linux/pinctrl/pinconf.h>
> +#include <linux/pinctrl/pinmux.h>
> +#include <linux/platform_device.h>
> +#include <linux/regulator/consumer.h>
> +#include <soc/tegra/pmc.h>
> +
> +#include "../core.h"
> +#include "../pinconf.h"
> +#include "../pinctrl-utils.h"
> +
> +/**
> + * Macro for 1.8V, keep 200mV as tolerance for deciding that
> + * IO pads should be set for 3.3V (high voltage) or 1.8V.
> + */
> +#define TEGRA_IO_PAD_1800000UV_UPPER_LIMIT 2000000
Is there a reference we could add for the source of this information?
> +
> +struct tegra_io_pads_cfg_info {
Nit-pick do you need the suffix '_info'? May be nice to keep the name
shorter and just have 'tegra_io_pads_cfg'
> + const char *name;
> + const unsigned int pins[1];
> + const char *vsupply;
> + enum tegra_io_pad pad_id;
Nit-pick, I think "id" would be sufficient here.
> + bool support_low_power_state;
I don't see where the above is used. I would also shorten to
"supports_low_power".
> +};
> +
> +struct tegra_io_pad_soc_data {
s/tegra_io_pad/tegra_io_pads/
> + const struct tegra_io_pads_cfg_info *pads_cfg;
> + int num_pads_cfg;
May be just ...
const struct tegra_io_pads_cfg_info *cfgs;
int num_cfgs;
> + const struct pinctrl_pin_desc *pins_desc;
> + int num_pins_desc;
> +};
> +
> +struct tegra_io_pads_regulator_info {
> + struct device *dev;
> + const struct tegra_io_pads_cfg_info *pads_cfg;
> + struct regulator *regulator;
> + struct notifier_block regulator_nb;
> +};
Is this struct necessary? Seems to be a lot of duplicated information
from the other structs. Why not add the regulator and regulator_nb to
the main struct? OK, not all io_pads have a regulator but you are only
saving one pointer.
> +
> +struct tegra_io_pads_info {
> + struct device *dev;
> + struct pinctrl_dev *pctl;
> + struct tegra_io_pads_regulator_info *rinfo;
> + const struct tegra_io_pad_soc_data *soc_data;
> +};
> +
> +static int tegra_iop_pinctrl_get_groups_count(struct pinctrl_dev *pctldev)
> +{
> + struct tegra_io_pads_info *tiopi = pinctrl_dev_get_drvdata(pctldev);
> +
> + return tiopi->soc_data->num_pads_cfg;
> +}
> +
> +static const char *tegra_iop_pinctrl_get_group_name(struct pinctrl_dev *pctldev,
> + unsigned int group)
> +{
> + struct tegra_io_pads_info *tiopi = pinctrl_dev_get_drvdata(pctldev);
> +
> + return tiopi->soc_data->pads_cfg[group].name;
> +}
> +
> +static int tegra_iop_pinctrl_get_group_pins(struct pinctrl_dev *pctldev,
> + unsigned int group,
> + const unsigned int **pins,
> + unsigned int *num_pins)
> +{
> + struct tegra_io_pads_info *tiopi = pinctrl_dev_get_drvdata(pctldev);
> +
> + *pins = tiopi->soc_data->pads_cfg[group].pins;
> + *num_pins = 1;
> +
> + return 0;
> +}
> +
> +static const struct pinctrl_ops tegra_iop_pinctrl_ops = {
> + .get_groups_count = tegra_iop_pinctrl_get_groups_count,
> + .get_group_name = tegra_iop_pinctrl_get_group_name,
> + .get_group_pins = tegra_iop_pinctrl_get_group_pins,
> + .dt_node_to_map = pinconf_generic_dt_node_to_map_pin,
> + .dt_free_map = pinctrl_utils_free_map,
> +};
> +
> +static int tegra_io_pad_pinconf_get(struct pinctrl_dev *pctldev,
> + unsigned int pin, unsigned long *config)
> +{
Seems to be a mixture of tegra_iop/tegra_io_pad/tegra_io_pads between
various function names. Would be good to be consistent.
> + struct tegra_io_pads_info *tiopi = pinctrl_dev_get_drvdata(pctldev);
> + int param = pinconf_to_config_param(*config);
> + const struct tegra_io_pads_cfg_info *pads_cfg =
> + &tiopi->soc_data->pads_cfg[pin];
> + enum tegra_io_pad pad_id = pads_cfg->pad_id;
> + int arg = 0;
Nit-pick, pad_id and arg seem unnecessary.
> + int ret;
> +
> + switch (param) {
> + case PIN_CONFIG_LOW_POWER_MODE:
> + ret = tegra_io_pad_power_get_status(pad_id);
> + if (ret < 0)
> + return ret;
> + arg = !ret;
> + break;
> +
> + default:
> + dev_err(tiopi->dev, "The parameter %d not supported\n", param);
> + return -EINVAL;
> + }
> +
> + *config = pinconf_to_config_packed(param, (u16)arg);
> + return 0;
> +}
> +
> +static int tegra_io_pad_pinconf_set(struct pinctrl_dev *pctldev,
> + unsigned int pin, unsigned long *configs,
> + unsigned int num_configs)
> +{
> + struct tegra_io_pads_info *tiopi = pinctrl_dev_get_drvdata(pctldev);
> + const struct tegra_io_pads_cfg_info *pads_cfg =
> + &tiopi->soc_data->pads_cfg[pin];
> + int pad_id = pads_cfg->pad_id;
Unnecessary variable?
> + u16 param_val;
> + int param;
> + int ret;
> + int i;
Nit-pick, can't the above be on one line?
> +
> + for (i = 0; i < num_configs; i++) {
> + param = pinconf_to_config_param(configs[i]);
> + param_val = pinconf_to_config_argument(configs[i]);
> +
> + switch (param) {
> + case PIN_CONFIG_LOW_POWER_MODE:
> + if (param_val)
> + ret = tegra_io_pad_power_disable(pad_id);
> + else
> + ret = tegra_io_pad_power_enable(pad_id);
> + if (ret < 0) {
> + dev_err(tiopi->dev,
> + "Failed to set DPD %d of pin %u: %d\n",
> + param_val, pin, ret);
> + return ret;
> + }
> + break;
> +
> + default:
> + dev_err(tiopi->dev, "The parameter %d not supported\n",
> + param);
> + return -EINVAL;
> + }
> + }
> +
> + return 0;
> +}
> +
> +static const struct pinconf_ops tegra_io_pad_pinconf_ops = {
> + .pin_config_get = tegra_io_pad_pinconf_get,
> + .pin_config_set = tegra_io_pad_pinconf_set,
> +};
> +
> +static struct pinctrl_desc tegra_iop_pinctrl_desc = {
> + .name = "pinctrl-tegra-io-pads",
> + .pctlops = &tegra_iop_pinctrl_ops,
> + .confops = &tegra_io_pad_pinconf_ops,
> +};
> +
> +static int tegra_io_pads_rail_change_notify_cb(struct notifier_block *nb,
> + unsigned long event, void *data)
> +{
> + struct tegra_io_pads_regulator_info *rinfo;
> + struct pre_voltage_change_data *vdata;
> + unsigned long int io_volt_uv, old_uv;
> + enum tegra_io_pad_voltage io_volt;
> + int ret;
> +
> + rinfo = container_of(nb, struct tegra_io_pads_regulator_info,
> + regulator_nb);
> +
> + switch (event) {
> + case REGULATOR_EVENT_PRE_VOLTAGE_CHANGE:
> + vdata = data;
> + if ((vdata->old_uV > TEGRA_IO_PAD_1800000UV_UPPER_LIMIT) &&
> + (vdata->min_uV <= TEGRA_IO_PAD_1800000UV_UPPER_LIMIT))
> + break;
The data-sheet for Tegra210 only lists 1.8V or 3.3V as supported
options. Do we need to support a range? Or does the h/w support a range
of voltages? I am just wondering why we cannot check explicitly for 1.8V
or 3.3V and treat anything else as an error.
> +
> + ret = tegra_io_pad_set_voltage(rinfo->pads_cfg->pad_id,
> + TEGRA_IO_PAD_3300000UV);
> + if (ret < 0) {
> + dev_err(rinfo->dev,
> + "Failed to set voltage %lu of pad %s: %d\n",
> + vdata->min_uV, rinfo->pads_cfg->name, ret);
> + return ret;
> + }
> + break;
> +
> + case REGULATOR_EVENT_VOLTAGE_CHANGE:
> + io_volt_uv = (unsigned long)data;
> + ret = tegra_io_pad_get_voltage(rinfo->pads_cfg->pad_id);
> + if (ret < 0) {
> + dev_err(rinfo->dev, "Failed to get IO pad voltage: %d\n",
> + ret);
> + return ret;
> + }
> + old_uv = (ret == TEGRA_IO_PAD_1800000UV) ? 1800000 : 3300000;
> + if (((io_volt_uv <= TEGRA_IO_PAD_1800000UV_UPPER_LIMIT) &&
> + (old_uv <= TEGRA_IO_PAD_1800000UV_UPPER_LIMIT)) ||
> + ((io_volt_uv > TEGRA_IO_PAD_1800000UV_UPPER_LIMIT) &&
> + (old_uv > TEGRA_IO_PAD_1800000UV_UPPER_LIMIT)))
> + break;
Macro or sub-function? It is hard to read.
> +
> + ret = tegra_io_pad_set_voltage(rinfo->pads_cfg->pad_id,
> + TEGRA_IO_PAD_1800000UV);
> + if (ret < 0) {
> + dev_err(rinfo->dev,
> + "Failed to set voltage %lu of pad %s: %d\n",
> + vdata->min_uV, rinfo->pads_cfg->name, ret);
> + return ret;
> + }
> + break;
> +
> + case REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE:
> + io_volt_uv = (unsigned long)data;
> + io_volt = (io_volt_uv <= TEGRA_IO_PAD_1800000UV_UPPER_LIMIT) ?
> + TEGRA_IO_PAD_1800000UV : TEGRA_IO_PAD_3300000UV;
Macro? I believe this is also used in another place.
> + ret = tegra_io_pad_set_voltage(rinfo->pads_cfg->pad_id,
> + io_volt);
> + if (ret < 0) {
> + dev_err(rinfo->dev,
> + "Failed to set voltage %lu of pad %s: %d\n",
> + io_volt_uv, rinfo->pads_cfg->name, ret);
> + return ret;
> + }
> + break;
> +
> + default:
> + break;
> + }
> +
> + return NOTIFY_OK;
> +}
> +
> +static int tegra_iop_pinctrl_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + const struct platform_device_id *id = platform_get_device_id(pdev);
> + const struct tegra_io_pad_soc_data *soc_data;
> + struct device_node *np_parent = pdev->dev.parent->of_node;
I would get rid of this variable and set pdev->dev.of_node right before
testing it is valid.
> + struct tegra_io_pads_info *tiopi;
> + int ret, i;
> +
> + if (!np_parent) {
> + dev_err(dev, "PMC should be register from DT\n");
> + return -ENODEV;
> + }
> +
> + soc_data = (const struct tegra_io_pad_soc_data *)id->driver_data;
> +
> + tiopi = devm_kzalloc(dev, sizeof(*tiopi), GFP_KERNEL);
> + if (!tiopi)
> + return -ENOMEM;
> +
> + tiopi->rinfo = devm_kzalloc(dev, sizeof(*tiopi->rinfo) *
> + soc_data->num_pads_cfg, GFP_KERNEL);
> + if (!tiopi->rinfo)
> + return -ENOMEM;
> +
> + tiopi->dev = &pdev->dev;
> + pdev->dev.of_node = np_parent;
> + tiopi->soc_data = soc_data;
> +
> + for (i = 0; i < soc_data->num_pads_cfg; ++i) {
> + struct tegra_io_pads_regulator_info *rinfo = tiopi->rinfo + i;
> + const struct tegra_io_pads_cfg_info *pads_cfg =
> + &soc_data->pads_cfg[i];
Is this variable necessary? Why not set rinfo->pads_cfg directly from
soc_data?
> + struct regulator *regulator;
> + int io_volt_uv;
> + enum tegra_io_pad_voltage io_volt;
> +
> + if (!pads_cfg->vsupply)
> + continue;
> +
> + regulator = devm_regulator_get_optional(dev, pads_cfg->vsupply);
> + if (IS_ERR(regulator)) {
> + ret = PTR_ERR(regulator);
> + if (ret == -EPROBE_DEFER)
> + return ret;
> + continue;
> + }
> +
> + io_volt_uv = regulator_get_voltage(regulator);
> + if (io_volt_uv < 0) {
> + dev_err(dev, "Failed to get voltage for rail %s: %d\n",
> + pads_cfg->vsupply, io_volt_uv);
> + return ret;
> + }
> +
> + io_volt = (io_volt_uv <= TEGRA_IO_PAD_1800000UV_UPPER_LIMIT) ?
> + TEGRA_IO_PAD_1800000UV : TEGRA_IO_PAD_3300000UV;
Macro?
> + ret = tegra_io_pad_set_voltage(pads_cfg->pad_id, io_volt);
> + if (ret < 0) {
> + dev_err(dev, "Failed to set voltage %d of pad %s: %d\n",
> + io_volt_uv, pads_cfg->name, ret);
> + return ret;
> + }
> + rinfo->dev = tiopi->dev;
> + rinfo->regulator = regulator;
> + rinfo->pads_cfg = pads_cfg;
> +
> + rinfo->regulator_nb.notifier_call =
> + tegra_io_pads_rail_change_notify_cb;
> + ret = devm_regulator_register_notifier(regulator,
> + &rinfo->regulator_nb);
> + if (ret < 0) {
> + dev_err(dev, "Failed to register regulator %s notifier: %d\n",
> + pads_cfg->name, ret);
> + return ret;
> + }
> + }
> +
> + tegra_iop_pinctrl_desc.pins = tiopi->soc_data->pins_desc;
> + tegra_iop_pinctrl_desc.npins = tiopi->soc_data->num_pins_desc;
> + platform_set_drvdata(pdev, tiopi);
> +
> + tiopi->pctl = devm_pinctrl_register(dev, &tegra_iop_pinctrl_desc,
> + tiopi);
> + if (IS_ERR(tiopi->pctl)) {
> + ret = PTR_ERR(tiopi->pctl);
> + dev_err(dev, "Failed to register io-pad pinctrl driver: %d\n",
> + ret);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +#define TEGRA124_PAD_INFO_TABLE(_entry_) \
> + _entry_(0, "audio", AUDIO, true, NULL), \
> + _entry_(1, "bb", BB, true, NULL), \
> + _entry_(2, "cam", CAM, true, NULL), \
> + _entry_(3, "comp", COMP, true, NULL), \
> + _entry_(4, "csia", CSIA, true, NULL), \
> + _entry_(5, "csib", CSIB, true, NULL), \
> + _entry_(6, "csie", CSIE, true, NULL), \
> + _entry_(7, "dsi", DSI, true, NULL), \
> + _entry_(8, "dsib", DSIB, true, NULL), \
> + _entry_(9, "dsic", DSIC, true, NULL), \
> + _entry_(10, "dsid", DSID, true, NULL), \
> + _entry_(11, "hdmi", HDMI, true, NULL), \
> + _entry_(12, "hsic", HSIC, true, NULL), \
> + _entry_(13, "hv", HV, true, NULL), \
> + _entry_(14, "lvds", LVDS, true, NULL), \
> + _entry_(15, "mipi-bias", MIPI_BIAS, true, NULL), \
> + _entry_(16, "nand", NAND, true, NULL), \
> + _entry_(17, "pex-bias", PEX_BIAS, true, NULL), \
> + _entry_(18, "pex-clk1", PEX_CLK1, true, NULL), \
> + _entry_(19, "pex-clk2", PEX_CLK2, true, NULL), \
> + _entry_(20, "pex-ctrl", PEX_CNTRL, true, NULL), \
> + _entry_(21, "sdmmc1", SDMMC1, true, NULL), \
> + _entry_(22, "sdmmc3", SDMMC3, true, NULL), \
> + _entry_(23, "sdmmc4", SDMMC4, true, NULL), \
> + _entry_(24, "sys-ddc", SYS_DDC, true, NULL), \
> + _entry_(25, "uart", UART, true, NULL), \
> + _entry_(26, "usb0", USB0, true, NULL), \
> + _entry_(27, "usb1", USB1, true, NULL), \
> + _entry_(28, "usb2", USB2, true, NULL), \
> + _entry_(29, "usb-bias", USB_BIAS, true, NULL)
> +
> +#define TEGRA210_PAD_INFO_TABLE(_entry_) \
> + _entry_(0, "audio", AUDIO, true, "vddio-audio"), \
> + _entry_(1, "audio-hv", AUDIO_HV, true, "vddio-audio-hv"), \
> + _entry_(2, "cam", CAM, true, "vddio-cam"), \
> + _entry_(3, "csia", CSIA, true, NULL), \
> + _entry_(4, "csib", CSIB, true, NULL), \
> + _entry_(5, "csic", CSIC, true, NULL), \
> + _entry_(6, "csid", CSID, true, NULL), \
> + _entry_(7, "csie", CSIE, true, NULL), \
> + _entry_(8, "csif", CSIF, true, NULL), \
> + _entry_(9, "dbg", DBG, true, "vddio-dbg"), \
> + _entry_(10, "debug-nonao", DEBUG_NONAO, true, NULL), \
> + _entry_(11, "dmic", DMIC, true, "vddio-dmic"), \
> + _entry_(12, "dp", DP, true, NULL), \
> + _entry_(13, "dsi", DSI, true, NULL), \
> + _entry_(14, "dsib", DSIB, true, NULL), \
> + _entry_(15, "dsic", DSIC, true, NULL), \
> + _entry_(16, "dsid", DSID, true, NULL), \
> + _entry_(17, "emmc", SDMMC4, true, NULL), \
> + _entry_(18, "emmc2", EMMC2, true, NULL), \
> + _entry_(19, "gpio", GPIO, true, "vddio-gpio"), \
> + _entry_(20, "hdmi", HDMI, true, NULL), \
> + _entry_(21, "hsic", HSIC, true, NULL), \
> + _entry_(22, "lvds", LVDS, true, NULL), \
> + _entry_(23, "mipi-bias", MIPI_BIAS, true, NULL), \
> + _entry_(24, "pex-bias", PEX_BIAS, true, NULL), \
> + _entry_(25, "pex-clk1", PEX_CLK1, true, NULL), \
> + _entry_(26, "pex-clk2", PEX_CLK2, true, NULL), \
> + _entry_(27, "pex-ctrl", PEX_CNTRL, false, "vddio-pex-ctrl"), \
> + _entry_(28, "sdmmc1", SDMMC1, true, "vddio-sdmmc1"), \
> + _entry_(29, "sdmmc3", SDMMC3, true, "vddio-sdmmc3"), \
> + _entry_(30, "spi", SPI, true, "vddio-spi"), \
> + _entry_(31, "spi-hv", SPI_HV, true, "vddio-spi-hv"), \
> + _entry_(32, "uart", UART, true, "vddio-uart"), \
> + _entry_(33, "usb0", USB0, true, NULL), \
> + _entry_(34, "usb1", USB1, true, NULL), \
> + _entry_(35, "usb2", USB2, true, NULL), \
> + _entry_(36, "usb3", USB3, true, NULL), \
> + _entry_(37, "usb-bias", USB_BIAS, true, NULL)
> +
> +#define TEGRA_IO_PAD_INFO(_id, _name, _pad_id, _lpstate, _vsupply) \
> + { \
> + .name = _name, \
Do we need to store 'name' in this struct as well seeing as it is
already in the pins_desc?
Cheers
Jon
--
nvpublic
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