// SPDX-License-Identifier: GPL-2.0
|
/*
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* Arche Platform driver to enable Unipro link.
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*
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* Copyright 2014-2015 Google Inc.
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* Copyright 2014-2015 Linaro Ltd.
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*/
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#include <linux/clk.h>
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#include <linux/delay.h>
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#include <linux/gpio/consumer.h>
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#include <linux/init.h>
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#include <linux/module.h>
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#include <linux/of_platform.h>
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#include <linux/pinctrl/consumer.h>
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#include <linux/platform_device.h>
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#include <linux/pm.h>
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#include <linux/interrupt.h>
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#include <linux/irq.h>
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#include <linux/suspend.h>
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#include <linux/time.h>
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#include <linux/greybus.h>
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#include "arche_platform.h"
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#if IS_ENABLED(CONFIG_USB_HSIC_USB3613)
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#include <linux/usb/usb3613.h>
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#else
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static inline int usb3613_hub_mode_ctrl(bool unused)
|
{
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return 0;
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}
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#endif
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|
#define WD_COLDBOOT_PULSE_WIDTH_MS 30
|
|
enum svc_wakedetect_state {
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WD_STATE_IDLE, /* Default state = pulled high/low */
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WD_STATE_BOOT_INIT, /* WD = falling edge (low) */
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WD_STATE_COLDBOOT_TRIG, /* WD = rising edge (high), > 30msec */
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WD_STATE_STANDBYBOOT_TRIG, /* As of now not used ?? */
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WD_STATE_COLDBOOT_START, /* Cold boot process started */
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WD_STATE_STANDBYBOOT_START, /* Not used */
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};
|
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struct arche_platform_drvdata {
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/* Control GPIO signals to and from AP <=> SVC */
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struct gpio_desc *svc_reset;
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bool is_reset_act_hi;
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struct gpio_desc *svc_sysboot;
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struct gpio_desc *wake_detect; /* bi-dir,maps to WAKE_MOD & WAKE_FRAME signals */
|
|
enum arche_platform_state state;
|
|
struct gpio_desc *svc_refclk_req;
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struct clk *svc_ref_clk;
|
|
struct pinctrl *pinctrl;
|
struct pinctrl_state *pin_default;
|
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int num_apbs;
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enum svc_wakedetect_state wake_detect_state;
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int wake_detect_irq;
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spinlock_t wake_lock; /* Protect wake_detect_state */
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struct mutex platform_state_mutex; /* Protect state */
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unsigned long wake_detect_start;
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struct notifier_block pm_notifier;
|
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struct device *dev;
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};
|
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/* Requires calling context to hold arche_pdata->platform_state_mutex */
|
static void arche_platform_set_state(struct arche_platform_drvdata *arche_pdata,
|
enum arche_platform_state state)
|
{
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arche_pdata->state = state;
|
}
|
|
/* Requires arche_pdata->wake_lock is held by calling context */
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static void arche_platform_set_wake_detect_state(
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struct arche_platform_drvdata *arche_pdata,
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enum svc_wakedetect_state state)
|
{
|
arche_pdata->wake_detect_state = state;
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}
|
|
static inline void svc_reset_onoff(struct gpio_desc *gpio, bool onoff)
|
{
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gpiod_set_raw_value(gpio, onoff);
|
}
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static int apb_cold_boot(struct device *dev, void *data)
|
{
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int ret;
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ret = apb_ctrl_coldboot(dev);
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if (ret)
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dev_warn(dev, "failed to coldboot\n");
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/*Child nodes are independent, so do not exit coldboot operation */
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return 0;
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}
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static int apb_poweroff(struct device *dev, void *data)
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{
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apb_ctrl_poweroff(dev);
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/* Enable HUB3613 into HUB mode. */
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if (usb3613_hub_mode_ctrl(false))
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dev_warn(dev, "failed to control hub device\n");
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return 0;
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}
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static void arche_platform_wd_irq_en(struct arche_platform_drvdata *arche_pdata)
|
{
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/* Enable interrupt here, to read event back from SVC */
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enable_irq(arche_pdata->wake_detect_irq);
|
}
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static irqreturn_t arche_platform_wd_irq_thread(int irq, void *devid)
|
{
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struct arche_platform_drvdata *arche_pdata = devid;
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unsigned long flags;
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spin_lock_irqsave(&arche_pdata->wake_lock, flags);
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if (arche_pdata->wake_detect_state != WD_STATE_COLDBOOT_TRIG) {
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/* Something is wrong */
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spin_unlock_irqrestore(&arche_pdata->wake_lock, flags);
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return IRQ_HANDLED;
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}
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arche_platform_set_wake_detect_state(arche_pdata,
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WD_STATE_COLDBOOT_START);
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spin_unlock_irqrestore(&arche_pdata->wake_lock, flags);
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/* It should complete power cycle, so first make sure it is poweroff */
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device_for_each_child(arche_pdata->dev, NULL, apb_poweroff);
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/* Bring APB out of reset: cold boot sequence */
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device_for_each_child(arche_pdata->dev, NULL, apb_cold_boot);
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/* Enable HUB3613 into HUB mode. */
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if (usb3613_hub_mode_ctrl(true))
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dev_warn(arche_pdata->dev, "failed to control hub device\n");
|
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spin_lock_irqsave(&arche_pdata->wake_lock, flags);
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arche_platform_set_wake_detect_state(arche_pdata, WD_STATE_IDLE);
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spin_unlock_irqrestore(&arche_pdata->wake_lock, flags);
|
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return IRQ_HANDLED;
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}
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static irqreturn_t arche_platform_wd_irq(int irq, void *devid)
|
{
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struct arche_platform_drvdata *arche_pdata = devid;
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unsigned long flags;
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spin_lock_irqsave(&arche_pdata->wake_lock, flags);
|
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if (gpiod_get_value(arche_pdata->wake_detect)) {
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/* wake/detect rising */
|
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/*
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* If wake/detect line goes high after low, within less than
|
* 30msec, then standby boot sequence is initiated, which is not
|
* supported/implemented as of now. So ignore it.
|
*/
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if (arche_pdata->wake_detect_state == WD_STATE_BOOT_INIT) {
|
if (time_before(jiffies,
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arche_pdata->wake_detect_start +
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msecs_to_jiffies(WD_COLDBOOT_PULSE_WIDTH_MS))) {
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arche_platform_set_wake_detect_state(arche_pdata,
|
WD_STATE_IDLE);
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} else {
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/*
|
* Check we are not in middle of irq thread
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* already
|
*/
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if (arche_pdata->wake_detect_state !=
|
WD_STATE_COLDBOOT_START) {
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arche_platform_set_wake_detect_state(arche_pdata,
|
WD_STATE_COLDBOOT_TRIG);
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spin_unlock_irqrestore(
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&arche_pdata->wake_lock,
|
flags);
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return IRQ_WAKE_THREAD;
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}
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}
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}
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} else {
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/* wake/detect falling */
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if (arche_pdata->wake_detect_state == WD_STATE_IDLE) {
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arche_pdata->wake_detect_start = jiffies;
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/*
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* In the beginning, when wake/detect goes low
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* (first time), we assume it is meant for coldboot
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* and set the flag. If wake/detect line stays low
|
* beyond 30msec, then it is coldboot else fallback
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* to standby boot.
|
*/
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arche_platform_set_wake_detect_state(arche_pdata,
|
WD_STATE_BOOT_INIT);
|
}
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}
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spin_unlock_irqrestore(&arche_pdata->wake_lock, flags);
|
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return IRQ_HANDLED;
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}
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/*
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* Requires arche_pdata->platform_state_mutex to be held
|
*/
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static int
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arche_platform_coldboot_seq(struct arche_platform_drvdata *arche_pdata)
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{
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int ret;
|
|
if (arche_pdata->state == ARCHE_PLATFORM_STATE_ACTIVE)
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return 0;
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dev_info(arche_pdata->dev, "Booting from cold boot state\n");
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svc_reset_onoff(arche_pdata->svc_reset, arche_pdata->is_reset_act_hi);
|
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gpiod_set_value(arche_pdata->svc_sysboot, 0);
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usleep_range(100, 200);
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ret = clk_prepare_enable(arche_pdata->svc_ref_clk);
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if (ret) {
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dev_err(arche_pdata->dev, "failed to enable svc_ref_clk: %d\n",
|
ret);
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return ret;
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}
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/* bring SVC out of reset */
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svc_reset_onoff(arche_pdata->svc_reset, !arche_pdata->is_reset_act_hi);
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arche_platform_set_state(arche_pdata, ARCHE_PLATFORM_STATE_ACTIVE);
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|
return 0;
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}
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/*
|
* Requires arche_pdata->platform_state_mutex to be held
|
*/
|
static int
|
arche_platform_fw_flashing_seq(struct arche_platform_drvdata *arche_pdata)
|
{
|
int ret;
|
|
if (arche_pdata->state == ARCHE_PLATFORM_STATE_FW_FLASHING)
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return 0;
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dev_info(arche_pdata->dev, "Switching to FW flashing state\n");
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svc_reset_onoff(arche_pdata->svc_reset, arche_pdata->is_reset_act_hi);
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gpiod_set_value(arche_pdata->svc_sysboot, 1);
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usleep_range(100, 200);
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ret = clk_prepare_enable(arche_pdata->svc_ref_clk);
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if (ret) {
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dev_err(arche_pdata->dev, "failed to enable svc_ref_clk: %d\n",
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ret);
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return ret;
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}
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svc_reset_onoff(arche_pdata->svc_reset, !arche_pdata->is_reset_act_hi);
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arche_platform_set_state(arche_pdata, ARCHE_PLATFORM_STATE_FW_FLASHING);
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return 0;
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}
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/*
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* Requires arche_pdata->platform_state_mutex to be held
|
*/
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static void
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arche_platform_poweroff_seq(struct arche_platform_drvdata *arche_pdata)
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{
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unsigned long flags;
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if (arche_pdata->state == ARCHE_PLATFORM_STATE_OFF)
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return;
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/* If in fw_flashing mode, then no need to repeate things again */
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if (arche_pdata->state != ARCHE_PLATFORM_STATE_FW_FLASHING) {
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disable_irq(arche_pdata->wake_detect_irq);
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spin_lock_irqsave(&arche_pdata->wake_lock, flags);
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arche_platform_set_wake_detect_state(arche_pdata,
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WD_STATE_IDLE);
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spin_unlock_irqrestore(&arche_pdata->wake_lock, flags);
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}
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clk_disable_unprepare(arche_pdata->svc_ref_clk);
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/* As part of exit, put APB back in reset state */
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svc_reset_onoff(arche_pdata->svc_reset, arche_pdata->is_reset_act_hi);
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arche_platform_set_state(arche_pdata, ARCHE_PLATFORM_STATE_OFF);
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}
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static ssize_t state_store(struct device *dev,
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struct device_attribute *attr,
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const char *buf, size_t count)
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{
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struct arche_platform_drvdata *arche_pdata = dev_get_drvdata(dev);
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int ret = 0;
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mutex_lock(&arche_pdata->platform_state_mutex);
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if (sysfs_streq(buf, "off")) {
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if (arche_pdata->state == ARCHE_PLATFORM_STATE_OFF)
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goto exit;
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/* If SVC goes down, bring down APB's as well */
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device_for_each_child(arche_pdata->dev, NULL, apb_poweroff);
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arche_platform_poweroff_seq(arche_pdata);
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|
} else if (sysfs_streq(buf, "active")) {
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if (arche_pdata->state == ARCHE_PLATFORM_STATE_ACTIVE)
|
goto exit;
|
|
/* First we want to make sure we power off everything
|
* and then activate back again
|
*/
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device_for_each_child(arche_pdata->dev, NULL, apb_poweroff);
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arche_platform_poweroff_seq(arche_pdata);
|
|
arche_platform_wd_irq_en(arche_pdata);
|
ret = arche_platform_coldboot_seq(arche_pdata);
|
if (ret)
|
goto exit;
|
|
} else if (sysfs_streq(buf, "standby")) {
|
if (arche_pdata->state == ARCHE_PLATFORM_STATE_STANDBY)
|
goto exit;
|
|
dev_warn(arche_pdata->dev, "standby state not supported\n");
|
} else if (sysfs_streq(buf, "fw_flashing")) {
|
if (arche_pdata->state == ARCHE_PLATFORM_STATE_FW_FLASHING)
|
goto exit;
|
|
/*
|
* Here we only control SVC.
|
*
|
* In case of FW_FLASHING mode we do not want to control
|
* APBs, as in case of V2, SPI bus is shared between both
|
* the APBs. So let user chose which APB he wants to flash.
|
*/
|
arche_platform_poweroff_seq(arche_pdata);
|
|
ret = arche_platform_fw_flashing_seq(arche_pdata);
|
if (ret)
|
goto exit;
|
} else {
|
dev_err(arche_pdata->dev, "unknown state\n");
|
ret = -EINVAL;
|
}
|
|
exit:
|
mutex_unlock(&arche_pdata->platform_state_mutex);
|
return ret ? ret : count;
|
}
|
|
static ssize_t state_show(struct device *dev,
|
struct device_attribute *attr, char *buf)
|
{
|
struct arche_platform_drvdata *arche_pdata = dev_get_drvdata(dev);
|
|
switch (arche_pdata->state) {
|
case ARCHE_PLATFORM_STATE_OFF:
|
return sprintf(buf, "off\n");
|
case ARCHE_PLATFORM_STATE_ACTIVE:
|
return sprintf(buf, "active\n");
|
case ARCHE_PLATFORM_STATE_STANDBY:
|
return sprintf(buf, "standby\n");
|
case ARCHE_PLATFORM_STATE_FW_FLASHING:
|
return sprintf(buf, "fw_flashing\n");
|
default:
|
return sprintf(buf, "unknown state\n");
|
}
|
}
|
|
static DEVICE_ATTR_RW(state);
|
|
static int arche_platform_pm_notifier(struct notifier_block *notifier,
|
unsigned long pm_event, void *unused)
|
{
|
struct arche_platform_drvdata *arche_pdata =
|
container_of(notifier, struct arche_platform_drvdata,
|
pm_notifier);
|
int ret = NOTIFY_DONE;
|
|
mutex_lock(&arche_pdata->platform_state_mutex);
|
switch (pm_event) {
|
case PM_SUSPEND_PREPARE:
|
if (arche_pdata->state != ARCHE_PLATFORM_STATE_ACTIVE) {
|
ret = NOTIFY_STOP;
|
break;
|
}
|
device_for_each_child(arche_pdata->dev, NULL, apb_poweroff);
|
arche_platform_poweroff_seq(arche_pdata);
|
break;
|
case PM_POST_SUSPEND:
|
if (arche_pdata->state != ARCHE_PLATFORM_STATE_OFF)
|
break;
|
|
arche_platform_wd_irq_en(arche_pdata);
|
arche_platform_coldboot_seq(arche_pdata);
|
break;
|
default:
|
break;
|
}
|
mutex_unlock(&arche_pdata->platform_state_mutex);
|
|
return ret;
|
}
|
|
static int arche_platform_probe(struct platform_device *pdev)
|
{
|
struct arche_platform_drvdata *arche_pdata;
|
struct device *dev = &pdev->dev;
|
struct device_node *np = dev->of_node;
|
int ret;
|
unsigned int flags;
|
|
arche_pdata = devm_kzalloc(&pdev->dev, sizeof(*arche_pdata),
|
GFP_KERNEL);
|
if (!arche_pdata)
|
return -ENOMEM;
|
|
/* setup svc reset gpio */
|
arche_pdata->is_reset_act_hi = of_property_read_bool(np,
|
"svc,reset-active-high");
|
if (arche_pdata->is_reset_act_hi)
|
flags = GPIOD_OUT_HIGH;
|
else
|
flags = GPIOD_OUT_LOW;
|
|
arche_pdata->svc_reset = devm_gpiod_get(dev, "svc,reset", flags);
|
if (IS_ERR(arche_pdata->svc_reset)) {
|
ret = PTR_ERR(arche_pdata->svc_reset);
|
dev_err(dev, "failed to request svc-reset GPIO: %d\n", ret);
|
return ret;
|
}
|
arche_platform_set_state(arche_pdata, ARCHE_PLATFORM_STATE_OFF);
|
|
arche_pdata->svc_sysboot = devm_gpiod_get(dev, "svc,sysboot",
|
GPIOD_OUT_LOW);
|
if (IS_ERR(arche_pdata->svc_sysboot)) {
|
ret = PTR_ERR(arche_pdata->svc_sysboot);
|
dev_err(dev, "failed to request sysboot0 GPIO: %d\n", ret);
|
return ret;
|
}
|
|
/* setup the clock request gpio first */
|
arche_pdata->svc_refclk_req = devm_gpiod_get(dev, "svc,refclk-req",
|
GPIOD_IN);
|
if (IS_ERR(arche_pdata->svc_refclk_req)) {
|
ret = PTR_ERR(arche_pdata->svc_refclk_req);
|
dev_err(dev, "failed to request svc-clk-req GPIO: %d\n", ret);
|
return ret;
|
}
|
|
/* setup refclk2 to follow the pin */
|
arche_pdata->svc_ref_clk = devm_clk_get(dev, "svc_ref_clk");
|
if (IS_ERR(arche_pdata->svc_ref_clk)) {
|
ret = PTR_ERR(arche_pdata->svc_ref_clk);
|
dev_err(dev, "failed to get svc_ref_clk: %d\n", ret);
|
return ret;
|
}
|
|
platform_set_drvdata(pdev, arche_pdata);
|
|
arche_pdata->num_apbs = of_get_child_count(np);
|
dev_dbg(dev, "Number of APB's available - %d\n", arche_pdata->num_apbs);
|
|
arche_pdata->wake_detect = devm_gpiod_get(dev, "svc,wake-detect",
|
GPIOD_IN);
|
if (IS_ERR(arche_pdata->wake_detect)) {
|
ret = PTR_ERR(arche_pdata->wake_detect);
|
dev_err(dev, "Failed requesting wake_detect GPIO: %d\n", ret);
|
return ret;
|
}
|
|
arche_platform_set_wake_detect_state(arche_pdata, WD_STATE_IDLE);
|
|
arche_pdata->dev = &pdev->dev;
|
|
spin_lock_init(&arche_pdata->wake_lock);
|
mutex_init(&arche_pdata->platform_state_mutex);
|
arche_pdata->wake_detect_irq =
|
gpiod_to_irq(arche_pdata->wake_detect);
|
|
ret = devm_request_threaded_irq(dev, arche_pdata->wake_detect_irq,
|
arche_platform_wd_irq,
|
arche_platform_wd_irq_thread,
|
IRQF_TRIGGER_FALLING |
|
IRQF_TRIGGER_RISING | IRQF_ONESHOT,
|
dev_name(dev), arche_pdata);
|
if (ret) {
|
dev_err(dev, "failed to request wake detect IRQ %d\n", ret);
|
return ret;
|
}
|
disable_irq(arche_pdata->wake_detect_irq);
|
|
ret = device_create_file(dev, &dev_attr_state);
|
if (ret) {
|
dev_err(dev, "failed to create state file in sysfs\n");
|
return ret;
|
}
|
|
ret = of_platform_populate(np, NULL, NULL, dev);
|
if (ret) {
|
dev_err(dev, "failed to populate child nodes %d\n", ret);
|
goto err_device_remove;
|
}
|
|
arche_pdata->pm_notifier.notifier_call = arche_platform_pm_notifier;
|
ret = register_pm_notifier(&arche_pdata->pm_notifier);
|
|
if (ret) {
|
dev_err(dev, "failed to register pm notifier %d\n", ret);
|
goto err_device_remove;
|
}
|
|
/* Explicitly power off if requested */
|
if (!of_property_read_bool(pdev->dev.of_node, "arche,init-off")) {
|
mutex_lock(&arche_pdata->platform_state_mutex);
|
ret = arche_platform_coldboot_seq(arche_pdata);
|
if (ret) {
|
dev_err(dev, "Failed to cold boot svc %d\n", ret);
|
goto err_coldboot;
|
}
|
arche_platform_wd_irq_en(arche_pdata);
|
mutex_unlock(&arche_pdata->platform_state_mutex);
|
}
|
|
dev_info(dev, "Device registered successfully\n");
|
return 0;
|
|
err_coldboot:
|
mutex_unlock(&arche_pdata->platform_state_mutex);
|
err_device_remove:
|
device_remove_file(&pdev->dev, &dev_attr_state);
|
return ret;
|
}
|
|
static int arche_remove_child(struct device *dev, void *unused)
|
{
|
struct platform_device *pdev = to_platform_device(dev);
|
|
platform_device_unregister(pdev);
|
|
return 0;
|
}
|
|
static int arche_platform_remove(struct platform_device *pdev)
|
{
|
struct arche_platform_drvdata *arche_pdata = platform_get_drvdata(pdev);
|
|
unregister_pm_notifier(&arche_pdata->pm_notifier);
|
device_remove_file(&pdev->dev, &dev_attr_state);
|
device_for_each_child(&pdev->dev, NULL, arche_remove_child);
|
arche_platform_poweroff_seq(arche_pdata);
|
|
if (usb3613_hub_mode_ctrl(false))
|
dev_warn(arche_pdata->dev, "failed to control hub device\n");
|
/* TODO: Should we do anything more here ?? */
|
return 0;
|
}
|
|
static __maybe_unused int arche_platform_suspend(struct device *dev)
|
{
|
/*
|
* If timing profile premits, we may shutdown bridge
|
* completely
|
*
|
* TODO: sequence ??
|
*
|
* Also, need to make sure we meet precondition for unipro suspend
|
* Precondition: Definition ???
|
*/
|
return 0;
|
}
|
|
static __maybe_unused int arche_platform_resume(struct device *dev)
|
{
|
/*
|
* Atleast for ES2 we have to meet the delay requirement between
|
* unipro switch and AP bridge init, depending on whether bridge is in
|
* OFF state or standby state.
|
*
|
* Based on whether bridge is in standby or OFF state we may have to
|
* assert multiple signals. Please refer to WDM spec, for more info.
|
*
|
*/
|
return 0;
|
}
|
|
static void arche_platform_shutdown(struct platform_device *pdev)
|
{
|
struct arche_platform_drvdata *arche_pdata = platform_get_drvdata(pdev);
|
|
arche_platform_poweroff_seq(arche_pdata);
|
|
usb3613_hub_mode_ctrl(false);
|
}
|
|
static SIMPLE_DEV_PM_OPS(arche_platform_pm_ops,
|
arche_platform_suspend,
|
arche_platform_resume);
|
|
static const struct of_device_id arche_platform_of_match[] = {
|
/* Use PID/VID of SVC device */
|
{ .compatible = "google,arche-platform", },
|
{ },
|
};
|
|
static const struct of_device_id arche_combined_id[] = {
|
/* Use PID/VID of SVC device */
|
{ .compatible = "google,arche-platform", },
|
{ .compatible = "usbffff,2", },
|
{ },
|
};
|
MODULE_DEVICE_TABLE(of, arche_combined_id);
|
|
static struct platform_driver arche_platform_device_driver = {
|
.probe = arche_platform_probe,
|
.remove = arche_platform_remove,
|
.shutdown = arche_platform_shutdown,
|
.driver = {
|
.name = "arche-platform-ctrl",
|
.pm = &arche_platform_pm_ops,
|
.of_match_table = arche_platform_of_match,
|
}
|
};
|
|
static int __init arche_init(void)
|
{
|
int retval;
|
|
retval = platform_driver_register(&arche_platform_device_driver);
|
if (retval)
|
return retval;
|
|
retval = arche_apb_init();
|
if (retval)
|
platform_driver_unregister(&arche_platform_device_driver);
|
|
return retval;
|
}
|
module_init(arche_init);
|
|
static void __exit arche_exit(void)
|
{
|
arche_apb_exit();
|
platform_driver_unregister(&arche_platform_device_driver);
|
}
|
module_exit(arche_exit);
|
|
MODULE_LICENSE("GPL v2");
|
MODULE_AUTHOR("Vaibhav Hiremath <vaibhav.hiremath@linaro.org>");
|
MODULE_DESCRIPTION("Arche Platform Driver");
|
