Commit 409c38d4 authored by Jinjian Song's avatar Jinjian Song Committed by David S. Miller
Browse files

net: wwan: t7xx: Add sysfs attribute for device state machine 



Add support for userspace to get/set the device mode, device's state
machine changes between (unknown/ready/reset/fastboot).

Get the device state mode:
 - 'cat /sys/bus/pci/devices/${bdf}/t7xx_mode'

Set the device state mode:
 - reset(cold reset): 'echo reset > /sys/bus/pci/devices/${bdf}/t7xx_mode'
 - fastboot: 'echo fastboot_switching > /sys/bus/pci/devices/${bdf}/t7xx_mode'
Reload driver to get the new device state after setting operation.

Signed-off-by: default avatarJinjian Song <jinjian.song@fibocom.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent e3caf184

Documentation/networking/device_drivers/wwan/t7xx.rst

+28 −0
Original line number Diff line number Diff line
@@ -39,6 +39,34 @@ command and receive response: 


- open the AT control channel using a UART tool or a special user tool



Sysfs

=====

The driver provides sysfs interfaces to userspace.



t7xx_mode

---------

The sysfs interface provides userspace with access to the device mode, this interface

supports read and write operations.



Device mode:



- ``unknown`` represents that device in unknown status

- ``ready`` represents that device in ready status

- ``reset`` represents that device in reset status

- ``fastboot_switching`` represents that device in fastboot switching status

- ``fastboot_download`` represents that device in fastboot download status

- ``fastboot_dump`` represents that device in fastboot dump status



Read from userspace to get the current device mode.



::

  $ cat /sys/bus/pci/devices/${bdf}/t7xx_mode



Write from userspace to set the device mode.



::

  $ echo fastboot_switching > /sys/bus/pci/devices/${bdf}/t7xx_mode



Management application development

==================================

The driver and userspace interfaces are described below. The MBIM protocol is

drivers/net/wwan/t7xx/t7xx_modem_ops.c

+6 −0
Original line number Diff line number Diff line
@@ -177,6 +177,11 @@ int t7xx_acpi_fldr_func(struct t7xx_pci_dev *t7xx_dev) 
	return t7xx_acpi_reset(t7xx_dev, "_RST");

}



int t7xx_acpi_pldr_func(struct t7xx_pci_dev *t7xx_dev)

{

	return t7xx_acpi_reset(t7xx_dev, "MRST._RST");

}



static void t7xx_reset_device_via_pmic(struct t7xx_pci_dev *t7xx_dev)

{

	u32 val;
@@ -192,6 +197,7 @@ static irqreturn_t t7xx_rgu_isr_thread(int irq, void *data) 
{

	struct t7xx_pci_dev *t7xx_dev = data;



	t7xx_mode_update(t7xx_dev, T7XX_RESET);

	msleep(RGU_RESET_DELAY_MS);

	t7xx_reset_device_via_pmic(t7xx_dev);

	return IRQ_HANDLED;

drivers/net/wwan/t7xx/t7xx_modem_ops.h

+1 −0
Original line number Diff line number Diff line
@@ -85,6 +85,7 @@ int t7xx_md_init(struct t7xx_pci_dev *t7xx_dev); 
void t7xx_md_exit(struct t7xx_pci_dev *t7xx_dev);

void t7xx_clear_rgu_irq(struct t7xx_pci_dev *t7xx_dev);

int t7xx_acpi_fldr_func(struct t7xx_pci_dev *t7xx_dev);

int t7xx_acpi_pldr_func(struct t7xx_pci_dev *t7xx_dev);

int t7xx_pci_mhccif_isr(struct t7xx_pci_dev *t7xx_dev);



#endif	/* __T7XX_MODEM_OPS_H__ */

drivers/net/wwan/t7xx/t7xx_pci.c

+96 −5
Original line number Diff line number Diff line
@@ -52,6 +52,81 @@ 
#define PM_RESOURCE_POLL_TIMEOUT_US	10000

#define PM_RESOURCE_POLL_STEP_US	100



static const char * const t7xx_mode_names[] = {

	[T7XX_UNKNOWN] = "unknown",

	[T7XX_READY] = "ready",

	[T7XX_RESET] = "reset",

	[T7XX_FASTBOOT_SWITCHING] = "fastboot_switching",

	[T7XX_FASTBOOT_DOWNLOAD] = "fastboot_download",

	[T7XX_FASTBOOT_DUMP] = "fastboot_dump",

};



static_assert(ARRAY_SIZE(t7xx_mode_names) == T7XX_MODE_LAST);



static ssize_t t7xx_mode_store(struct device *dev,

			       struct device_attribute *attr,

			       const char *buf, size_t count)

{

	struct t7xx_pci_dev *t7xx_dev;

	struct pci_dev *pdev;

	int index = 0;



	pdev = to_pci_dev(dev);

	t7xx_dev = pci_get_drvdata(pdev);

	if (!t7xx_dev)

		return -ENODEV;



	index = sysfs_match_string(t7xx_mode_names, buf);

	if (index == T7XX_FASTBOOT_SWITCHING) {

		WRITE_ONCE(t7xx_dev->mode, T7XX_FASTBOOT_SWITCHING);

	} else if (index == T7XX_RESET) {

		WRITE_ONCE(t7xx_dev->mode, T7XX_RESET);

		t7xx_acpi_pldr_func(t7xx_dev);

	}



	return count;

};



static ssize_t t7xx_mode_show(struct device *dev,

			      struct device_attribute *attr,

			      char *buf)

{

	enum t7xx_mode mode = T7XX_UNKNOWN;

	struct t7xx_pci_dev *t7xx_dev;

	struct pci_dev *pdev;



	pdev = to_pci_dev(dev);

	t7xx_dev = pci_get_drvdata(pdev);

	if (!t7xx_dev)

		return -ENODEV;



	mode = READ_ONCE(t7xx_dev->mode);

	if (mode < T7XX_MODE_LAST)

		return sysfs_emit(buf, "%s\n", t7xx_mode_names[mode]);



	return sysfs_emit(buf, "%s\n", t7xx_mode_names[T7XX_UNKNOWN]);

}



static DEVICE_ATTR_RW(t7xx_mode);



static struct attribute *t7xx_mode_attr[] = {

	&dev_attr_t7xx_mode.attr,

	NULL

};



static const struct attribute_group t7xx_mode_attribute_group = {

	.attrs = t7xx_mode_attr,

};



void t7xx_mode_update(struct t7xx_pci_dev *t7xx_dev, enum t7xx_mode mode)

{

	if (!t7xx_dev)

		return;



	WRITE_ONCE(t7xx_dev->mode, mode);

	sysfs_notify(&t7xx_dev->pdev->dev.kobj, NULL, "t7xx_mode");

}



enum t7xx_pm_state {

	MTK_PM_EXCEPTION,

	MTK_PM_INIT,		/* Device initialized, but handshake not completed */
@@ -279,7 +354,8 @@ static int __t7xx_pci_pm_suspend(struct pci_dev *pdev) 
	int ret;



	t7xx_dev = pci_get_drvdata(pdev);

	if (atomic_read(&t7xx_dev->md_pm_state) <= MTK_PM_INIT) {

	if (atomic_read(&t7xx_dev->md_pm_state) <= MTK_PM_INIT ||

	    READ_ONCE(t7xx_dev->mode) != T7XX_READY) {

		dev_err(&pdev->dev, "[PM] Exiting suspend, modem in invalid state\n");

		return -EFAULT;

	}
@@ -729,16 +805,28 @@ static int t7xx_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) 


	t7xx_pcie_mac_interrupts_dis(t7xx_dev);



	ret = sysfs_create_group(&t7xx_dev->pdev->dev.kobj,

				 &t7xx_mode_attribute_group);

	if (ret)

		goto err_md_exit;



	ret = t7xx_interrupt_init(t7xx_dev);

	if (ret) {

		t7xx_md_exit(t7xx_dev);

		return ret;

	}

	if (ret)

		goto err_remove_group;





	t7xx_pcie_mac_set_int(t7xx_dev, MHCCIF_INT);

	t7xx_pcie_mac_interrupts_en(t7xx_dev);



	return 0;



err_remove_group:

	sysfs_remove_group(&t7xx_dev->pdev->dev.kobj,

			   &t7xx_mode_attribute_group);



err_md_exit:

	t7xx_md_exit(t7xx_dev);

	return ret;

}



static void t7xx_pci_remove(struct pci_dev *pdev)
@@ -747,6 +835,9 @@ static void t7xx_pci_remove(struct pci_dev *pdev) 
	int i;



	t7xx_dev = pci_get_drvdata(pdev);



	sysfs_remove_group(&t7xx_dev->pdev->dev.kobj,

			   &t7xx_mode_attribute_group);

	t7xx_md_exit(t7xx_dev);



	for (i = 0; i < EXT_INT_NUM; i++) {

drivers/net/wwan/t7xx/t7xx_pci.h

+13 −1
Original line number Diff line number Diff line
@@ -43,6 +43,16 @@ struct t7xx_addr_base { 


typedef irqreturn_t (*t7xx_intr_callback)(int irq, void *param);



enum t7xx_mode {

	T7XX_UNKNOWN,

	T7XX_READY,

	T7XX_RESET,

	T7XX_FASTBOOT_SWITCHING,

	T7XX_FASTBOOT_DOWNLOAD,

	T7XX_FASTBOOT_DUMP,

	T7XX_MODE_LAST, /* must always be last */

};



/* struct t7xx_pci_dev - MTK device context structure

 * @intr_handler: array of handler function for request_threaded_irq

 * @intr_thread: array of thread_fn for request_threaded_irq
@@ -59,6 +69,7 @@ typedef irqreturn_t (*t7xx_intr_callback)(int irq, void *param); 
 * @md_pm_lock: protects PCIe sleep lock

 * @sleep_disable_count: PCIe L1.2 lock counter

 * @sleep_lock_acquire: indicates that sleep has been disabled

 * @mode: indicates the device mode

 */

struct t7xx_pci_dev {

	t7xx_intr_callback	intr_handler[EXT_INT_NUM];
@@ -82,6 +93,7 @@ struct t7xx_pci_dev { 
#ifdef CONFIG_WWAN_DEBUGFS

	struct dentry		*debugfs_dir;

#endif

	u32			mode;

};



enum t7xx_pm_id {
@@ -120,5 +132,5 @@ int t7xx_pci_pm_entity_register(struct t7xx_pci_dev *t7xx_dev, struct md_pm_enti 
int t7xx_pci_pm_entity_unregister(struct t7xx_pci_dev *t7xx_dev, struct md_pm_entity *pm_entity);

void t7xx_pci_pm_init_late(struct t7xx_pci_dev *t7xx_dev);

void t7xx_pci_pm_exp_detected(struct t7xx_pci_dev *t7xx_dev);



void t7xx_mode_update(struct t7xx_pci_dev *t7xx_dev, enum t7xx_mode mode);

#endif /* __T7XX_PCI_H__ */