[PATCH V2 3/5] usb: xhci: tegra: Add genpd support

Jon Hunter
2018-09-28T14:11:48Z

The generic power-domain framework has been updated to allow devices
that require more than one power-domain to create a new device for
each power-domain required and then link these new power-domain
devices to the consumer device.

Update the Tegra xHCI driver to use the new APIs provided by the
generic power-domain framework so we can use the generic power-domain
framework for managing the xHCI controllers power-domains. Please
note that to maintain backward compatibility with older device-tree
blobs these new generic power-domain APIs are only used if the
'power-domains' property is present and otherwise we fall back to
using the legacy Tegra APIs for managing the power-domains.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
---
drivers/usb/host/xhci-tegra.c | 89 +++++++++++++++++++++++++++++++++++++------
1 file changed, 77 insertions(+), 12 deletions(-)

diff --git a/drivers/usb/host/xhci-tegra.c b/drivers/usb/host/xhci-tegra.c
index a586a7930a3d..696008ecc26e 100644
--- a/drivers/usb/host/xhci-tegra.c
+++ b/drivers/usb/host/xhci-tegra.c
@@ -18,6 +18,7 @@
#include <linux/phy/tegra/xusb.h>
#include <linux/platform_device.h>
#include <linux/pm.h>
+#include <linux/pm_domain.h>
#include <linux/pm_runtime.h>
#include <linux/regulator/consumer.h>
#include <linux/reset.h>
@@ -194,6 +195,11 @@ struct tegra_xusb {
struct reset_control *host_rst;
struct reset_control *ss_rst;

+ struct device *genpd_dev_host;
+ struct device *genpd_dev_ss;
+ struct device_link *genpd_dl_host;
+ struct device_link *genpd_dl_ss;
+
struct phy **phys;
unsigned int num_phys;

@@ -928,6 +934,57 @@ static int tegra_xusb_load_firmware(struct tegra_xusb *tegra)
return 0;
}

+static void tegra_xusb_powerdomain_remove(struct device *dev,
+ struct tegra_xusb *tegra)
+{
+ if (tegra->genpd_dl_ss)
+ device_link_del(tegra->genpd_dl_ss);
+ if (tegra->genpd_dl_host)
+ device_link_del(tegra->genpd_dl_host);
+ if (tegra->genpd_dev_ss)
+ dev_pm_domain_detach(tegra->genpd_dev_ss, true);
+ if (tegra->genpd_dev_host)
+ dev_pm_domain_detach(tegra->genpd_dev_host, true);
+}
+
+static int tegra_xusb_powerdomain_init(struct device *dev,
+ struct tegra_xusb *tegra)
+{
+ int err;
+
+ tegra->genpd_dev_host = dev_pm_domain_attach_by_name(dev, "xusb_host");
+ if (IS_ERR(tegra->genpd_dev_host)) {
+ err = PTR_ERR(tegra->genpd_dev_host);
+ dev_err(dev, "failed to get host pm-domain: %d\n", err);
+ return err;
+ }
+
+ tegra->genpd_dev_ss = dev_pm_domain_attach_by_name(dev, "xusb_ss");
+ if (IS_ERR(tegra->genpd_dev_ss)) {
+ err = PTR_ERR(tegra->genpd_dev_ss);
+ dev_err(dev, "failed to get superspeed pm-domain: %d\n", err);
+ return err;
+ }
+
+ tegra->genpd_dl_host = device_link_add(dev, tegra->genpd_dev_host,
+ DL_FLAG_PM_RUNTIME |
+ DL_FLAG_STATELESS);
+ if (!tegra->genpd_dl_host) {
+ dev_err(dev, "adding host device link failed!\n");
+ return -ENODEV;
+ }
+
+ tegra->genpd_dl_ss = device_link_add(dev, tegra->genpd_dev_ss,
+ DL_FLAG_PM_RUNTIME |
+ DL_FLAG_STATELESS);
+ if (!tegra->genpd_dl_ss) {
+ dev_err(dev, "adding superspeed device link failed!\n");
+ return -ENODEV;
+ }
+
+ return 0;
+}
+
static int tegra_xusb_probe(struct platform_device *pdev)
{
struct tegra_xusb_mbox_msg msg;
@@ -1038,7 +1095,7 @@ static int tegra_xusb_probe(struct platform_device *pdev)
goto put_padctl;
}

- if (!pdev->dev.pm_domain) {
+ if (!of_property_read_bool(pdev->dev.of_node, "power-domains")) {
tegra->host_rst = devm_reset_control_get(&pdev->dev,
"xusb_host");
if (IS_ERR(tegra->host_rst)) {
@@ -1069,17 +1126,22 @@ static int tegra_xusb_probe(struct platform_device *pdev)
tegra->host_clk,
tegra->host_rst);
if (err) {
+ tegra_powergate_power_off(TEGRA_POWERGATE_XUSBA);
dev_err(&pdev->dev,
"failed to enable XUSBC domain: %d\n", err);
- goto disable_xusba;
+ goto put_padctl;
}
+ } else {
+ err = tegra_xusb_powerdomain_init(&pdev->dev, tegra);
+ if (err)
+ goto put_powerdomains;
}

tegra->supplies = devm_kcalloc(&pdev->dev, tegra->soc->num_supplies,
sizeof(*tegra->supplies), GFP_KERNEL);
if (!tegra->supplies) {
err = -ENOMEM;
- goto disable_xusbc;
+ goto put_powerdomains;
}

for (i = 0; i < tegra->soc->num_supplies; i++)
@@ -1089,7 +1151,7 @@ static int tegra_xusb_probe(struct platform_device *pdev)
tegra->supplies);
if (err) {
dev_err(&pdev->dev, "failed to get regulators: %d\n", err);
- goto disable_xusbc;
+ goto put_powerdomains;
}

for (i = 0; i < tegra->soc->num_types; i++)
@@ -1099,7 +1161,7 @@ static int tegra_xusb_probe(struct platform_device *pdev)
sizeof(*tegra->phys), GFP_KERNEL);
if (!tegra->phys) {
err = -ENOMEM;
- goto disable_xusbc;
+ goto put_powerdomains;
}

for (i = 0, k = 0; i < tegra->soc->num_types; i++) {
@@ -1115,7 +1177,7 @@ static int tegra_xusb_probe(struct platform_device *pdev)
"failed to get PHY %s: %ld\n", prop,
PTR_ERR(phy));
err = PTR_ERR(phy);
- goto disable_xusbc;
+ goto put_powerdomains;
}

tegra->phys[k++] = phy;
@@ -1126,7 +1188,7 @@ static int tegra_xusb_probe(struct platform_device *pdev)
dev_name(&pdev->dev));
if (!tegra->hcd) {
err = -ENOMEM;
- goto disable_xusbc;
+ goto put_powerdomains;
}

/*
@@ -1222,12 +1284,13 @@ static int tegra_xusb_probe(struct platform_device *pdev)
disable_rpm:
pm_runtime_disable(&pdev->dev);
usb_put_hcd(tegra->hcd);
-disable_xusbc:
- if (!pdev->dev.pm_domain)
+put_powerdomains:
+ if (!of_property_read_bool(pdev->dev.of_node, "power-domains")) {
tegra_powergate_power_off(TEGRA_POWERGATE_XUSBC);
-disable_xusba:
- if (!pdev->dev.pm_domain)
tegra_powergate_power_off(TEGRA_POWERGATE_XUSBA);
+ } else {
+ tegra_xusb_powerdomain_remove(&pdev->dev, tegra);
+ }
put_padctl:
tegra_xusb_padctl_put(tegra->padctl);
return err;
@@ -1249,9 +1312,11 @@ static int tegra_xusb_remove(struct platform_device *pdev)
pm_runtime_put_sync(&pdev->dev);
pm_runtime_disable(&pdev->dev);

- if (!pdev->dev.pm_domain) {
+ if (!of_property_read_bool(pdev->dev.of_node, "power-domains")) {
tegra_powergate_power_off(TEGRA_POWERGATE_XUSBC);
tegra_powergate_power_off(TEGRA_POWERGATE_XUSBA);
+ } else {
+ tegra_xusb_powerdomain_remove(&pdev->dev, tegra);
}

tegra_xusb_padctl_put(tegra->padctl);
--
2.7.4