// SPDX-License-Identifier: GPL-2.0
/*
* Motorola Mapphone MDM6600 modem GPIO controlled USB PHY driver
* Copyright (C) 2018 Tony Lindgren <tony@atomide.com>
*/
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/gpio/consumer.h>
#include <linux/of_platform.h>
#include <linux/phy/phy.h>
#define PHY_MDM6600_PHY_DELAY_MS 4000 /* PHY enable 2.2s to 3.5s */
#define PHY_MDM6600_ENABLED_DELAY_MS 8000 /* 8s more total for MDM6600 */
#define MDM6600_MODEM_IDLE_DELAY_MS 1000 /* modem after USB suspend */
#define MDM6600_MODEM_WAKE_DELAY_MS 200 /* modem response after idle */
enum phy_mdm6600_ctrl_lines {
PHY_MDM6600_ENABLE, /* USB PHY enable */
PHY_MDM6600_POWER, /* Device power */
PHY_MDM6600_RESET, /* Device reset */
PHY_MDM6600_NR_CTRL_LINES,
};
enum phy_mdm6600_bootmode_lines {
PHY_MDM6600_MODE0, /* out USB mode0 and OOB wake */
PHY_MDM6600_MODE1, /* out USB mode1, in OOB wake */
PHY_MDM6600_NR_MODE_LINES,
};
enum phy_mdm6600_cmd_lines {
PHY_MDM6600_CMD0,
PHY_MDM6600_CMD1,
PHY_MDM6600_CMD2,
PHY_MDM6600_NR_CMD_LINES,
};
enum phy_mdm6600_status_lines {
PHY_MDM6600_STATUS0,
PHY_MDM6600_STATUS1,
PHY_MDM6600_STATUS2,
PHY_MDM6600_NR_STATUS_LINES,
};
/*
* MDM6600 command codes. These are based on Motorola Mapphone Linux
* kernel tree.
*/
enum phy_mdm6600_cmd {
PHY_MDM6600_CMD_BP_PANIC_ACK,
PHY_MDM6600_CMD_DATA_ONLY_BYPASS, /* Reroute USB to CPCAP PHY */
PHY_MDM6600_CMD_FULL_BYPASS, /* Reroute USB to CPCAP PHY */
PHY_MDM6600_CMD_NO_BYPASS, /* Request normal USB mode */
PHY_MDM6600_CMD_BP_SHUTDOWN_REQ, /* Request device power off */
PHY_MDM6600_CMD_BP_UNKNOWN_5,
PHY_MDM6600_CMD_BP_UNKNOWN_6,
PHY_MDM6600_CMD_UNDEFINED,
};
/*
* MDM6600 status codes. These are based on Motorola Mapphone Linux
* kernel tree.
*/
enum phy_mdm6600_status {
PHY_MDM6600_STATUS_PANIC, /* Seems to be really off */
PHY_MDM6600_STATUS_PANIC_BUSY_WAIT,
PHY_MDM6600_STATUS_QC_DLOAD,
PHY_MDM6600_STATUS_RAM_DOWNLOADER, /* MDM6600 USB flashing mode */
PHY_MDM6600_STATUS_PHONE_CODE_AWAKE, /* MDM6600 normal USB mode */
PHY_MDM6600_STATUS_PHONE_CODE_ASLEEP,
PHY_MDM6600_STATUS_SHUTDOWN_ACK,
PHY_MDM6600_STATUS_UNDEFINED,
};
static const char * const
phy_mdm6600_status_name[] = {
"off", "busy", "qc_dl", "ram_dl", "awake",
"asleep", "shutdown", "undefined",
};
struct phy_mdm6600 {
struct device *dev;
struct phy *generic_phy;
struct phy_provider *phy_provider;
struct gpio_desc *ctrl_gpios[PHY_MDM6600_NR_CTRL_LINES];
struct gpio_descs *mode_gpios;
struct gpio_descs *status_gpios;
struct gpio_descs *cmd_gpios;
struct delayed_work bootup_work;
struct delayed_work status_work;
struct delayed_work modem_wake_work;
struct completion ack;
bool enabled; /* mdm6600 phy enabled */
bool running; /* mdm6600 boot done */
bool awake; /* mdm6600 respnds on n_gsm */
int status;
};
static int phy_mdm6600_init(struct phy *x)
{
struct phy_mdm6600 *ddata = phy_get_drvdata(x);
struct gpio_desc *enable_gpio = ddata->ctrl_gpios[PHY_MDM6600_ENABLE];
if (!ddata->enabled)
return -EPROBE_DEFER;
gpiod_set_value_cansleep(enable_gpio, 0);
return 0;
}
static int phy_mdm6600_power_on(struct phy *x)
{
struct phy_mdm6600 *ddata = phy_get_drvdata(x);
struct gpio_desc *enable_gpio = ddata->ctrl_gpios[PHY_MDM6600_ENABLE];
if (!ddata->enabled)
return -ENODEV;
gpiod_set_value_cansleep(enable_gpio, 1);
return 0;
}
static int phy_mdm6600_power_off(struct phy *x)
{
struct phy_mdm6600 *ddata = phy_get_drvdata(x);
struct gpio_desc *enable_gpio = ddata->ctrl_gpios[PHY_MDM6600_ENABLE];
if (!ddata->enabled)
return -ENODEV;
gpiod_set_value_cansleep(enable_gpio, 0);
return 0;
}
static const struct phy_ops gpio_usb_ops = {
.init = phy_mdm6600_init,
.power_on = phy_mdm6600_power_on,
.power_off = phy_mdm6600_power_off,
.owner = THIS_MODULE,
};
/**
* phy_mdm6600_cmd() - send a command request to mdm6600
* @ddata: device driver data
*
* Configures the three command request GPIOs to the specified value.
*/
static void phy_mdm6600_cmd(struct phy_mdm6600 *ddata, int val)
{
int values[PHY_MDM6600_NR_CMD_LINES];
int i;
val &= (1 << PHY_MDM6600_NR_CMD_LINES) - 1;
for (i = 0; i < PHY_MDM6600_NR_CMD_LINES; i++)
values[i] = (val & BIT(i)) >> i;
gpiod_set_array_value_cansleep(PHY_MDM6600_NR_CMD_LINES,
ddata->cmd_gpios->desc, values);
}
/**
* phy_mdm6600_status() - read mdm6600 status lines
* @ddata: device driver data
*/
static void phy_mdm6600_status(struct work_struct *work)
{
struct phy_mdm6600 *ddata;
struct device *dev;
int values[PHY_MDM6600_NR_STATUS_LINES];
int error, i, val = 0;
ddata = container_of(work, struct phy_mdm6600, status_work.work);
dev = ddata->dev;
error = gpiod_get_array_value_cansleep(PHY_MDM6600_NR_CMD_LINES,
ddata->status_gpios->desc,
values);
if (error)
return;
for (i = 0; i < PHY_MDM6600_NR_CMD_LINES; i++) {
val |= values[i] << i;
dev_dbg(ddata->dev, "XXX %s: i: %i values[i]: %i val: %i\n",
__func__, i, values[i], val);
}
ddata->status = val;
dev_info(dev, "modem status: %i %s\n",
ddata->status,
phy_mdm6600_status_name[ddata->status & 7]);
complete(&ddata->ack);
}
static irqreturn_t phy_mdm6600_irq_thread(int irq, void *data)
{
struct phy_mdm6600 *ddata = data;
schedule_delayed_work(&ddata->status_work, msecs_to_jiffies(10));
return IRQ_HANDLED;
}
/**
* phy_mdm6600_wakeirq_thread - handle mode1 line OOB wake after booting
* @irq: interrupt
* @data: interrupt handler data
*
* GPIO mode1 is used initially as output to configure the USB boot
* mode for mdm6600. After booting it is used as input for OOB wake
* signal from mdm6600 to the SoC. Just use it for debug info only
* for now.
*/
static irqreturn_t phy_mdm6600_wakeirq_thread(int irq, void *data)
{
struct phy_mdm6600 *ddata = data;
struct gpio_desc *mode_gpio1;
mode_gpio1 = ddata->mode_gpios->desc[PHY_MDM6600_MODE1];
dev_dbg(ddata->dev, "OOB wake on mode_gpio1: %i\n",
gpiod_get_value(mode_gpio1));
return IRQ_HANDLED;
}
/**
* phy_mdm6600_init_irq() - initialize mdm6600 status IRQ lines
* @ddata: device driver data
*/
static void phy_mdm6600_init_irq(struct phy_mdm6600 *ddata)
{
struct device *dev = ddata->dev;
int i, error, irq;
for (i = PHY_MDM6600_STATUS0;
i <= PHY_MDM6600_STATUS2; i++) {
struct gpio_desc *gpio = ddata->status_gpios->desc[i];
irq = gpiod_to_irq(gpio);
if (irq <= 0)
continue;
error = devm_request_threaded_irq(dev, irq, NULL,
phy_mdm6600_irq_thread,
IRQF_TRIGGER_RISING |
IRQF_TRIGGER_FALLING |
IRQF_ONESHOT,
"mdm6600",
ddata);
if (error)
dev_warn(dev, "no modem status irq%i: %i\n",
irq, error);
}
}
struct phy_mdm6600_map {
const char *name;
int direction;
};
static const struct phy_mdm6600_map
phy_mdm6600_ctrl_gpio_map[PHY_MDM6600_NR_CTRL_LINES] = {
{ "enable", GPIOD_OUT_LOW, }, /* low = phy disabled */
{ "power", GPIOD_OUT_LOW, }, /* low = off */
{ "reset", GPIOD_OUT_HIGH, }, /* high = reset */
};
/**
* phy_mdm6600_init_lines() - initialize mdm6600 GPIO lines
* @ddata: device driver data
*/
static int phy_mdm6600_init_lines(struct phy_mdm6600 *ddata)
{
struct device *dev = ddata->dev;
int i;
/* MDM6600 control lines */
for (i = 0; i < ARRAY_SIZE(phy_mdm6600_ctrl_gpio_map); i++) {
const struct phy_mdm6600_map *map =
&phy_mdm6600_ctrl_gpio_map[i];
struct gpio_desc **gpio = &ddata->ctrl_gpios[i];
*gpio = devm_gpiod_get(dev, map->name, map->direction);
if (IS_ERR(*gpio)) {
dev_info(dev, "gpio %s error %li\n",
map->name, PTR_ERR(*gpio));
return PTR_ERR(*gpio);
}
}
/* MDM6600 USB start-up mode output lines */
ddata->mode_gpios = devm_gpiod_get_array(dev, "motorola,mode",
GPIOD_OUT_LOW);
if (IS_ERR(ddata->mode_gpios))
return PTR_ERR(ddata->mode_gpios);
if (ddata->mode_gpios->ndescs != PHY_MDM6600_NR_MODE_LINES)
return -EINVAL;
/* MDM6600 status input lines */
ddata->status_gpios = devm_gpiod_get_array(dev, "motorola,status",
GPIOD_IN);
if (IS_ERR(ddata->status_gpios))
return PTR_ERR(ddata->status_gpios);
if (ddata->status_gpios->ndescs != PHY_MDM6600_NR_STATUS_LINES)
return -EINVAL;
/* MDM6600 cmd output lines */
ddata->cmd_gpios = devm_gpiod_get_array(dev, "motorola,cmd",
GPIOD_OUT_LOW);
if (IS_ERR(ddata->cmd_gpios))
return PTR_ERR(ddata->cmd_gpios);
if (ddata->cmd_gpios->ndescs != PHY_MDM6600_NR_CMD_LINES)
return -EINVAL;
return 0;
}
/**
* phy_mdm6600_device_power_on() - power on mdm6600 device
* @ddata: device driver data
*
* To get the integrated USB phy in MDM6600 takes some hoops. We must ensure
* the shared USB bootmode GPIOs are configured, then request modem start-up,
* reset and power-up.. And then we need to recycle the shared USB bootmode
* GPIOs as they are also used for Out of Band (OOB) wake for the USB and
* TS 27.010 serial mux.
*/
static int phy_mdm6600_device_power_on(struct phy_mdm6600 *ddata)
{
struct gpio_desc *mode_gpio0, *mode_gpio1, *reset_gpio, *power_gpio;
int error = 0, wakeirq;
mode_gpio0 = ddata->mode_gpios->desc[PHY_MDM6600_MODE0];
mode_gpio1 = ddata->mode_gpios->desc[PHY_MDM6600_MODE1];
reset_gpio = ddata->ctrl_gpios[PHY_MDM6600_RESET];
power_gpio = ddata->ctrl_gpios[PHY_MDM6600_POWER];
/*
* Shared GPIOs must be low for normal USB mode. After booting
* they are used for OOB wake signaling. These can be also used
* to configure USB flashing mode later on based on a module
* parameter.
*/
gpiod_set_value_cansleep(mode_gpio0, 0);
gpiod_set_value_cansleep(mode_gpio1, 0);
/* Request start-up mode */
phy_mdm6600_cmd(ddata, PHY_MDM6600_CMD_NO_BYPASS);
/* Request a reset first */
gpiod_set_value_cansleep(reset_gpio, 0);
msleep(100);
/* Toggle power GPIO to request mdm6600 to start */
gpiod_set_value_cansleep(power_gpio, 1);
msleep(100);
gpiod_set_value_cansleep(power_gpio, 0);
/*
* Looks like the USB PHY needs between 2.2 to 4 seconds.
* If we try to use it before that, we will get L3 errors
* from omap-usb-host trying to access the PHY. See also
* phy_mdm6600_init() for -EPROBE_DEFER.
*/
msleep(PHY_MDM6600_PHY_DELAY_MS);
ddata->enabled = true;
/* Booting up the rest of MDM6600 will take total about 8 seconds */
dev_info(ddata->dev, "Waiting for power up request to complete..\n");
if (wait_for_completion_timeout(&ddata->ack,
msecs_to_jiffies(PHY_MDM6600_ENABLED_DELAY_MS))) {
if (ddata->status > PHY_MDM6600_STATUS_PANIC &&
ddata->status < PHY_MDM6600_STATUS_SHUTDOWN_ACK)
dev_info(ddata->dev, "Powered up OK\n");
} else {
ddata->enabled = false;
error = -ETIMEDOUT;
dev_err(ddata->dev, "Timed out powering up\n");
}
/* Reconfigure mode1 GPIO as input for OOB wake */
gpiod_direction_input(mode_gpio1);
wakeirq = gpiod_to_irq(mode_gpio1);
if (wakeirq <= 0)
return wakeirq;
error = devm_request_threaded_irq(ddata->dev, wakeirq, NULL,
phy_mdm6600_wakeirq_thread,
IRQF_TRIGGER_RISING |
IRQF_TRIGGER_FALLING |
IRQF_ONESHOT,
"mdm6600-wake",
ddata);
if (error)
dev_warn(ddata->dev, "no modem wakeirq irq%i: %i\n",
wakeirq, error);
ddata->running = true;
return error;
}
/**
* phy_mdm6600_device_power_off() - power off mdm6600 device
* @ddata: device driver data
*/
static void phy_mdm6600_device_power_off(struct phy_mdm6600 *ddata)
{
struct gpio_desc *reset_gpio =
ddata->ctrl_gpios[PHY_MDM6600_RESET];
ddata->enabled = false;
phy_mdm6600_cmd(ddata, PHY_MDM6600_CMD_BP_SHUTDOWN_REQ);
msleep(100);
gpiod_set_value_cansleep(reset_gpio, 1);
dev_info(ddata->dev, "Waiting for power down request to complete.. ");
if (wait_for_completion_timeout(&ddata->ack,
msecs_to_jiffies(5000))) {
if (ddata->status == PHY_MDM6600_STATUS_PANIC)
dev_info(ddata->dev, "Powered down OK\n");
} else {
dev_err(ddata->dev, "Timed out powering down\n");
}
}
static void phy_mdm6600_deferred_power_on(struct work_struct *work)
{
struct phy_mdm6600 *ddata;
int error;
ddata = container_of(work, struct phy_mdm6600, bootup_work.work);
error = phy_mdm6600_device_power_on(ddata);
if (error)
dev_err(ddata->dev, "Device not functional\n");
}
/*
* USB suspend puts mdm6600 into low power mode. For any n_gsm using apps,
* we need to keep the modem awake by kicking it's mode0 GPIO. This will
* keep the modem awake for about 1.2 seconds. When no n_gsm apps are using
* the modem, runtime PM auto mode can be enabled so modem can enter low
* power mode.
*/
static void phy_mdm6600_wake_modem(struct phy_mdm6600 *ddata)
{
struct gpio_desc *mode_gpio0;
mode_gpio0 = ddata->mode_gpios->desc[PHY_MDM6600_MODE0];
gpiod_set_value_cansleep(mode_gpio0, 1);
usleep_range(5, 15);
gpiod_set_value_cansleep(mode_gpio0, 0);
if (ddata->awake)
usleep_range(5, 15);
else
msleep(MDM6600_MODEM_WAKE_DELAY_MS);
}
static void phy_mdm6600_modem_wake(struct work_struct *work)
{
struct phy_mdm6600 *ddata;
ddata = container_of(work, struct phy_mdm6600, modem_wake_work.work);
phy_mdm6600_wake_modem(ddata);
schedule_delayed_work(&ddata->modem_wake_work,
msecs_to_jiffies(MDM6600_MODEM_IDLE_DELAY_MS));
}
static int __maybe_unused phy_mdm6600_runtime_suspend(struct device *dev)
{
struct phy_mdm6600 *ddata = dev_get_drvdata(dev);
cancel_delayed_work_sync(&ddata->modem_wake_work);
ddata->awake = false;
return 0;
}
static int __maybe_unused phy_mdm6600_runtime_resume(struct device *dev)
{
struct phy_mdm6600 *ddata = dev_get_drvdata(dev);
phy_mdm6600_modem_wake(&ddata->modem_wake_work.work);
ddata->awake = true;
return 0;
}
static const struct dev_pm_ops phy_mdm6600_pm_ops = {
SET_RUNTIME_PM_OPS(phy_mdm6600_runtime_suspend,
phy_mdm6600_runtime_resume, NULL)
};
static const struct of_device_id phy_mdm6600_id_table[] = {
{ .compatible = "motorola,mapphone-mdm6600", },
{},
};
MODULE_DEVICE_TABLE(of, phy_mdm6600_id_table);
static int phy_mdm6600_probe(struct platform_device *pdev)
{
struct phy_mdm6600 *ddata;
int error;
ddata = devm_kzalloc(&pdev->dev, sizeof(*ddata), GFP_KERNEL);
if (!ddata)
return -ENOMEM;
INIT_DELAYED_WORK(&ddata->bootup_work,
phy_mdm6600_deferred_power_on);
INIT_DELAYED_WORK(&ddata->status_work, phy_mdm6600_status);
INIT_DELAYED_WORK(&ddata->modem_wake_work, phy_mdm6600_modem_wake);
init_completion(&ddata->ack);
ddata->dev = &pdev->dev;
platform_set_drvdata(pdev, ddata);
error = phy_mdm6600_init_lines(ddata);
if (error)
return error;
phy_mdm6600_init_irq(ddata);
ddata->generic_phy = devm_phy_create(ddata->dev, NULL, &gpio_usb_ops);
if (IS_ERR(ddata->generic_phy)) {
error = PTR_ERR(ddata->generic_phy);
goto cleanup;
}
phy_set_drvdata(ddata->generic_phy, ddata);
ddata->phy_provider =
devm_of_phy_provider_register(ddata->dev,
of_phy_simple_xlate);
if (IS_ERR(ddata->phy_provider)) {
error = PTR_ERR(ddata->phy_provider);
goto cleanup;
}
schedule_delayed_work(&ddata->bootup_work, 0);
/*
* See phy_mdm6600_device_power_on(). We should be able
* to remove this eventually when ohci-platform can deal
* with -EPROBE_DEFER.
*/
msleep(PHY_MDM6600_PHY_DELAY_MS + 500);
/*
* Enable PM runtime only after PHY has been powered up properly.
* It is currently only needed after USB suspends mdm6600 and n_gsm
* needs to access the device. We don't want to do this earlier as
* gpio mode0 pin doubles as mdm6600 wake-up gpio.
*/
pm_runtime_use_autosuspend(ddata->dev);
pm_runtime_set_autosuspend_delay(ddata->dev,
MDM6600_MODEM_IDLE_DELAY_MS);
pm_runtime_enable(ddata->dev);
error = pm_runtime_get_sync(ddata->dev);
if (error < 0) {
dev_warn(ddata->dev, "failed to wake modem: %i\n", error);
pm_runtime_put_noidle(ddata->dev);
}
pm_runtime_mark_last_busy(ddata->dev);
pm_runtime_put_autosuspend(ddata->dev);
return 0;
cleanup:
phy_mdm6600_device_power_off(ddata);
return error;
}
static int phy_mdm6600_remove(struct platform_device *pdev)
{
struct phy_mdm6600 *ddata = platform_get_drvdata(pdev);
struct gpio_desc *reset_gpio = ddata->ctrl_gpios[PHY_MDM6600_RESET];
pm_runtime_dont_use_autosuspend(ddata->dev);
pm_runtime_put_sync(ddata->dev);
pm_runtime_disable(ddata->dev);
if (!ddata->running)
wait_for_completion_timeout(&ddata->ack,
msecs_to_jiffies(PHY_MDM6600_ENABLED_DELAY_MS));
gpiod_set_value_cansleep(reset_gpio, 1);
phy_mdm6600_device_power_off(ddata);
cancel_delayed_work_sync(&ddata->modem_wake_work);
cancel_delayed_work_sync(&ddata->bootup_work);
cancel_delayed_work_sync(&ddata->status_work);
return 0;
}
static struct platform_driver phy_mdm6600_driver = {
.probe = phy_mdm6600_probe,
.remove = phy_mdm6600_remove,
.driver = {
.name = "phy-mapphone-mdm6600",
.pm = &phy_mdm6600_pm_ops,
.of_match_table = of_match_ptr(phy_mdm6600_id_table),
},
};
module_platform_driver(phy_mdm6600_driver);
MODULE_ALIAS("platform:gpio_usb");
MODULE_AUTHOR("Tony Lindgren <tony@atomide.com>");
MODULE_DESCRIPTION("mdm6600 gpio usb phy driver");
MODULE_LICENSE("GPL v2");
