| Message ID | 20230516182541.5836-3-mario.limonciello@amd.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Adjust logic for power_supply_is_system_supplied() | expand |
On Tue, May 16, 2023 at 01:25:41PM -0500, Mario Limonciello wrote: > power_supply_is_system_supplied() checks whether any power > supplies are present that aren't batteries to decide whether > the system is running on DC or AC. Downstream drivers use > this to make performance decisions. > > Navi dGPUs include an UCSI function that has been exported > since commit 17631e8ca2d3 ("i2c: designware: Add driver > support for AMD NAVI GPU"). > > This UCSI function registers a power supply since commit > 992a60ed0d5e ("usb: typec: ucsi: register with power_supply class") > but this is not a system power supply. > > As the power supply for a dGPU is only for powering devices connected > to dGPU, create a device property to indicate that the UCSI endpoint > is only for the scope of `POWER_SUPPLY_SCOPE_DEVICE`. ... > +static const struct property_entry dgpu_properties[] = { > + /* USB-C doesn't power the system */ > + PROPERTY_ENTRY_U8("scope", POWER_SUPPLY_SCOPE_DEVICE), > + {}, Comma is not needed in terminator entry. > +};
On Wed, May 17, 2023 at 08:14:13PM +0300, Andy Shevchenko wrote: > On Tue, May 16, 2023 at 01:25:41PM -0500, Mario Limonciello wrote: > > power_supply_is_system_supplied() checks whether any power > > supplies are present that aren't batteries to decide whether > > the system is running on DC or AC. Downstream drivers use > > this to make performance decisions. > > > > Navi dGPUs include an UCSI function that has been exported > > since commit 17631e8ca2d3 ("i2c: designware: Add driver > > support for AMD NAVI GPU"). > > > > This UCSI function registers a power supply since commit > > 992a60ed0d5e ("usb: typec: ucsi: register with power_supply class") > > but this is not a system power supply. > > > > As the power supply for a dGPU is only for powering devices connected > > to dGPU, create a device property to indicate that the UCSI endpoint > > is only for the scope of `POWER_SUPPLY_SCOPE_DEVICE`. > > ... > > > +static const struct property_entry dgpu_properties[] = { > > + /* USB-C doesn't power the system */ > > + PROPERTY_ENTRY_U8("scope", POWER_SUPPLY_SCOPE_DEVICE), > > + {}, > > Comma is not needed in terminator entry. But it's encouraged!
On Wed, May 17, 2023 at 08:58:49PM +0200, Greg KH wrote: > On Wed, May 17, 2023 at 08:14:13PM +0300, Andy Shevchenko wrote: > > On Tue, May 16, 2023 at 01:25:41PM -0500, Mario Limonciello wrote: ... > > > +static const struct property_entry dgpu_properties[] = { > > > + /* USB-C doesn't power the system */ > > > + PROPERTY_ENTRY_U8("scope", POWER_SUPPLY_SCOPE_DEVICE), > > > + {}, > > > > Comma is not needed in terminator entry. > > But it's encouraged! Why?! This might lead to the subtle mistakes going unnoticed during rebases. Yes, it's quite unlikely, but it might be still possible to have the empty entry in the middle of the array. Why should we shoot ourselves in the foot if we can avoid it without any effort? Hence I can say it's discouraged.
[AMD Official Use Only - General] > -----Original Message----- > From: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > Sent: Wednesday, May 17, 2023 2:14 PM > To: Greg KH <greg@kroah.com> > Cc: Limonciello, Mario <Mario.Limonciello@amd.com>; > heikki.krogerus@linux.intel.com; rafael@kernel.org; ajayg@nvidia.com; linux- > i2c@vger.kernel.org; linux-pm@vger.kernel.org; linux-kernel@vger.kernel.org; > linux-usb@vger.kernel.org; Quan, Evan <Evan.Quan@amd.com>; Lazar, Lijo > <Lijo.Lazar@amd.com>; Goswami, Sanket <Sanket.Goswami@amd.com> > Subject: Re: [PATCH 2/2] usb: typec: ucsi: Don't create power supplies for > dGPUs > > On Wed, May 17, 2023 at 08:58:49PM +0200, Greg KH wrote: > > On Wed, May 17, 2023 at 08:14:13PM +0300, Andy Shevchenko wrote: > > > On Tue, May 16, 2023 at 01:25:41PM -0500, Mario Limonciello wrote: > > ... > > > > > +static const struct property_entry dgpu_properties[] = { > > > > + /* USB-C doesn't power the system */ > > > > + PROPERTY_ENTRY_U8("scope", POWER_SUPPLY_SCOPE_DEVICE), > > > > + {}, > > > > > > Comma is not needed in terminator entry. > > > > But it's encouraged! > > Why?! This might lead to the subtle mistakes going unnoticed during rebases. > Yes, it's quite unlikely, but it might be still possible to have the empty > entry in the middle of the array. Why should we shoot ourselves in the foot > if we can avoid it without any effort? > > Hence I can say it's discouraged. > I tend to agree with Andy here, you should never be placing something after the terminator entry and putting a comma there means a mistake /can/ happen. I will pick up the tags and respin a v2 with this changed and patch 1 dropped since it went through another tree.
diff --git a/drivers/i2c/busses/i2c-designware-pcidrv.c b/drivers/i2c/busses/i2c-designware-pcidrv.c index 782fe1ef3ca1..048ffa18def0 100644 --- a/drivers/i2c/busses/i2c-designware-pcidrv.c +++ b/drivers/i2c/busses/i2c-designware-pcidrv.c @@ -20,6 +20,7 @@ #include <linux/module.h> #include <linux/pci.h> #include <linux/pm_runtime.h> +#include <linux/power_supply.h> #include <linux/sched.h> #include <linux/slab.h> @@ -234,6 +235,16 @@ static const struct dev_pm_ops i2c_dw_pm_ops = { SET_RUNTIME_PM_OPS(i2c_dw_pci_runtime_suspend, i2c_dw_pci_runtime_resume, NULL) }; +static const struct property_entry dgpu_properties[] = { + /* USB-C doesn't power the system */ + PROPERTY_ENTRY_U8("scope", POWER_SUPPLY_SCOPE_DEVICE), + {}, +}; + +static const struct software_node dgpu_node = { + .properties = dgpu_properties, +}; + static int i2c_dw_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) { @@ -325,7 +336,7 @@ static int i2c_dw_pci_probe(struct pci_dev *pdev, } if ((dev->flags & MODEL_MASK) == MODEL_AMD_NAVI_GPU) { - dev->slave = i2c_new_ccgx_ucsi(&dev->adapter, dev->irq, NULL); + dev->slave = i2c_new_ccgx_ucsi(&dev->adapter, dev->irq, &dgpu_node); if (IS_ERR(dev->slave)) return dev_err_probe(dev->dev, PTR_ERR(dev->slave), "register UCSI failed\n"); diff --git a/drivers/i2c/busses/i2c-nvidia-gpu.c b/drivers/i2c/busses/i2c-nvidia-gpu.c index a8b99e7f6262..26622d24bb1b 100644 --- a/drivers/i2c/busses/i2c-nvidia-gpu.c +++ b/drivers/i2c/busses/i2c-nvidia-gpu.c @@ -14,6 +14,7 @@ #include <linux/platform_device.h> #include <linux/pm.h> #include <linux/pm_runtime.h> +#include <linux/power_supply.h> #include <asm/unaligned.h> @@ -261,6 +262,8 @@ MODULE_DEVICE_TABLE(pci, gpu_i2c_ids); static const struct property_entry ccgx_props[] = { /* Use FW built for NVIDIA GPU only */ PROPERTY_ENTRY_STRING("firmware-name", "nvidia,gpu"), + /* USB-C doesn't power the system */ + PROPERTY_ENTRY_U8("scope", POWER_SUPPLY_SCOPE_DEVICE), { } }; diff --git a/drivers/usb/typec/ucsi/psy.c b/drivers/usb/typec/ucsi/psy.c index 56bf56517f75..384b42267f1f 100644 --- a/drivers/usb/typec/ucsi/psy.c +++ b/drivers/usb/typec/ucsi/psy.c @@ -27,8 +27,20 @@ static enum power_supply_property ucsi_psy_props[] = { POWER_SUPPLY_PROP_VOLTAGE_NOW, POWER_SUPPLY_PROP_CURRENT_MAX, POWER_SUPPLY_PROP_CURRENT_NOW, + POWER_SUPPLY_PROP_SCOPE, }; +static int ucsi_psy_get_scope(struct ucsi_connector *con, + union power_supply_propval *val) +{ + u8 scope = POWER_SUPPLY_SCOPE_UNKNOWN; + struct device *dev = con->ucsi->dev; + + device_property_read_u8(dev, "scope", &scope); + val->intval = scope; + return 0; +} + static int ucsi_psy_get_online(struct ucsi_connector *con, union power_supply_propval *val) { @@ -194,6 +206,8 @@ static int ucsi_psy_get_prop(struct power_supply *psy, return ucsi_psy_get_current_max(con, val); case POWER_SUPPLY_PROP_CURRENT_NOW: return ucsi_psy_get_current_now(con, val); + case POWER_SUPPLY_PROP_SCOPE: + return ucsi_psy_get_scope(con, val); default: return -EINVAL; }
power_supply_is_system_supplied() checks whether any power supplies are present that aren't batteries to decide whether the system is running on DC or AC. Downstream drivers use this to make performance decisions. Navi dGPUs include an UCSI function that has been exported since commit 17631e8ca2d3 ("i2c: designware: Add driver support for AMD NAVI GPU"). This UCSI function registers a power supply since commit 992a60ed0d5e ("usb: typec: ucsi: register with power_supply class") but this is not a system power supply. As the power supply for a dGPU is only for powering devices connected to dGPU, create a device property to indicate that the UCSI endpoint is only for the scope of `POWER_SUPPLY_SCOPE_DEVICE`. Cc: Evan Quan <Evan.Quan@amd.com> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> --- drivers/i2c/busses/i2c-designware-pcidrv.c | 13 ++++++++++++- drivers/i2c/busses/i2c-nvidia-gpu.c | 3 +++ drivers/usb/typec/ucsi/psy.c | 14 ++++++++++++++ 3 files changed, 29 insertions(+), 1 deletion(-)