Commit 553a64b7 authored by Hans de Goede's avatar Hans de Goede Committed by Mauro Carvalho Chehab
Browse files

media: atomisp: Move power-management over to a custom pm-domain 



The atomisp does not use standard PCI power-management through the
PCI config space. Instead this driver directly tells the P-Unit to
disable the ISP over the IOSF. The standard PCI subsystem pm_ops will
try to access the config space before (resume) / after (suspend) this
driver has turned the ISP on / off, resulting in the following errors:

 Unable to change power state from D0 to D3hot, device inaccessible
 Unable to change power state from D3cold to D0, device inaccessible

Getting logged into dmesg a whole bunch of time during boot as well as
every time the camera is used.

To avoid these errors use a custom pm_domain instead of standard driver
pm-callbacks so that all the PCI subsys suspend / resume handling is
skipped and call pci_save_state() / pci_restore_state() ourselves.

Signed-off-by: default avatarHans de Goede <hdegoede@redhat.com>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@kernel.org>
parent 21b86873

drivers/staging/media/atomisp/pci/atomisp_internal.h

+1 −0
Original line number Diff line number Diff line
@@ -210,6 +210,7 @@ struct atomisp_device { 
	void __iomem *base;

	const struct firmware *firmware;



	struct dev_pm_domain pm_domain;

	struct pm_qos_request pm_qos;

	s32 max_isr_latency;

drivers/staging/media/atomisp/pci/atomisp_v4l2.c

+32 −12
Original line number Diff line number Diff line
@@ -19,6 +19,7 @@ 
 */

#include <linux/module.h>

#include <linux/pci.h>

#include <linux/pm_domain.h>

#include <linux/pm_runtime.h>

#include <linux/pm_qos.h>

#include <linux/timer.h>
@@ -524,7 +525,7 @@ static int atomisp_save_iunit_reg(struct atomisp_device *isp) 
	return 0;

}



static int __maybe_unused atomisp_restore_iunit_reg(struct atomisp_device *isp)

static int atomisp_restore_iunit_reg(struct atomisp_device *isp)

{

	struct pci_dev *pdev = to_pci_dev(isp->dev);
@@ -662,6 +663,7 @@ static void punit_ddr_dvfs_enable(bool enable) 


static int atomisp_mrfld_power(struct atomisp_device *isp, bool enable)

{

	struct pci_dev *pdev = to_pci_dev(isp->dev);

	unsigned long timeout;

	u32 val = enable ? MRFLD_ISPSSPM0_IUNIT_POWER_ON :

			   MRFLD_ISPSSPM0_IUNIT_POWER_OFF;
@@ -703,6 +705,7 @@ static int atomisp_mrfld_power(struct atomisp_device *isp, bool enable) 
		tmp = (tmp >> MRFLD_ISPSSPM0_ISPSSS_OFFSET) & MRFLD_ISPSSPM0_ISPSSC_MASK;

		if (tmp == val) {

			trace_ipu_cstate(enable);

			pdev->current_state = enable ? PCI_D0 : PCI_D3cold;

			return 0;

		}
@@ -743,6 +746,7 @@ int atomisp_power_off(struct device *dev) 
	pci_write_config_dword(pdev, MRFLD_PCI_CSI_CONTROL, reg);



	cpu_latency_qos_update_request(&isp->pm_qos, PM_QOS_DEFAULT_VALUE);

	pci_save_state(pdev);

	return atomisp_mrfld_power(isp, false);

}
@@ -756,6 +760,7 @@ int atomisp_power_on(struct device *dev) 
	if (ret)

		return ret;



	pci_restore_state(to_pci_dev(dev));

	cpu_latency_qos_update_request(&isp->pm_qos, isp->max_isr_latency);



	/*restore register values for iUnit and iUnitPHY registers*/
@@ -767,7 +772,7 @@ int atomisp_power_on(struct device *dev) 
	return atomisp_css_init(isp);

}



static int __maybe_unused atomisp_suspend(struct device *dev)

static int atomisp_suspend(struct device *dev)

{

	struct atomisp_device *isp = (struct atomisp_device *)

				     dev_get_drvdata(dev);
@@ -790,10 +795,12 @@ static int __maybe_unused atomisp_suspend(struct device *dev) 
	}

	spin_unlock_irqrestore(&isp->lock, flags);



	pm_runtime_resume(dev);



	return atomisp_power_off(dev);

}



static int __maybe_unused atomisp_resume(struct device *dev)

static int atomisp_resume(struct device *dev)

{

	return atomisp_power_on(dev);

}
@@ -1603,6 +1610,26 @@ static int atomisp_pci_probe(struct pci_dev *pdev, const struct pci_device_id *i 
	/* save the iunit context only once after all the values are init'ed. */

	atomisp_save_iunit_reg(isp);



	/*

	 * The atomisp does not use standard PCI power-management through the

	 * PCI config space. Instead this driver directly tells the P-Unit to

	 * disable the ISP over the IOSF. The standard PCI subsystem pm_ops will

	 * try to access the config space before (resume) / after (suspend) this

	 * driver has turned the ISP on / off, resulting in the following errors:

	 *

	 * "Unable to change power state from D0 to D3hot, device inaccessible"

	 * "Unable to change power state from D3cold to D0, device inaccessible"

	 *

	 * To avoid these errors override the pm_domain so that all the PCI

	 * subsys suspend / resume handling is skipped.

	 */

	isp->pm_domain.ops.runtime_suspend = atomisp_power_off;

	isp->pm_domain.ops.runtime_resume = atomisp_power_on;

	isp->pm_domain.ops.suspend = atomisp_suspend;

	isp->pm_domain.ops.resume = atomisp_resume;



	dev_pm_domain_set(&pdev->dev, &isp->pm_domain);



	pm_runtime_put_noidle(&pdev->dev);

	pm_runtime_allow(&pdev->dev);
@@ -1645,6 +1672,7 @@ static int atomisp_pci_probe(struct pci_dev *pdev, const struct pci_device_id *i 
request_irq_fail:

	hmm_cleanup();

	pm_runtime_get_noresume(&pdev->dev);

	dev_pm_domain_set(&pdev->dev, NULL);

	atomisp_unregister_entities(isp);

register_entities_fail:

	atomisp_uninitialize_modules(isp);
@@ -1697,6 +1725,7 @@ static void atomisp_pci_remove(struct pci_dev *pdev) 


	pm_runtime_forbid(&pdev->dev);

	pm_runtime_get_noresume(&pdev->dev);

	dev_pm_domain_set(&pdev->dev, NULL);

	cpu_latency_qos_remove_request(&isp->pm_qos);



	atomisp_msi_irq_uninit(isp);
@@ -1721,17 +1750,8 @@ static const struct pci_device_id atomisp_pci_tbl[] = { 


MODULE_DEVICE_TABLE(pci, atomisp_pci_tbl);



static const struct dev_pm_ops atomisp_pm_ops = {

	.runtime_suspend = atomisp_power_off,

	.runtime_resume = atomisp_power_on,

	.suspend = atomisp_suspend,

	.resume = atomisp_resume,

};



static struct pci_driver atomisp_pci_driver = {

	.driver = {

		.pm = &atomisp_pm_ops,

	},

	.name = "atomisp-isp2",

	.id_table = atomisp_pci_tbl,

	.probe = atomisp_pci_probe,