| Message ID | 3ef0a090-13ef-4fa9-9b91-1b03abfd01f4@gmail.com |
|---|---|
| State | Accepted |
| Headers | show |
| Series | [RESUBMIT] i2c: i801: replace acpi_lock with I2C bus lock | expand |
On Wed, 20 Sep 2023 09:33:01 +0200, Heiner Kallweit wrote: > I2C core ensures in i2c_smbus_xfer() that the I2C bus lock is held when > calling the smbus_xfer callback. That's i801_access() in our case. > I think it's safe in general to assume that the I2C bus lock is held > when the smbus_xfer callback is called. > Therefore I see no need to define an own mutex. > > Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> > --- > Patch was part of a broken-up previous series. > --- > drivers/i2c/busses/i2c-i801.c | 14 ++++---------- > 1 file changed, 4 insertions(+), 10 deletions(-) > > diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c > index 26f132277..a485dc84d 100644 > --- a/drivers/i2c/busses/i2c-i801.c > +++ b/drivers/i2c/busses/i2c-i801.c > @@ -293,10 +293,9 @@ struct i801_priv { > > /* > * If set to true the host controller registers are reserved for > - * ACPI AML use. Protected by acpi_lock. > + * ACPI AML use. > */ > bool acpi_reserved; > - struct mutex acpi_lock; > }; > > #define FEATURE_SMBUS_PEC BIT(0) > @@ -874,11 +873,8 @@ static s32 i801_access(struct i2c_adapter *adap, u16 addr, > int hwpec, ret; > struct i801_priv *priv = i2c_get_adapdata(adap); > > - mutex_lock(&priv->acpi_lock); > - if (priv->acpi_reserved) { > - mutex_unlock(&priv->acpi_lock); > + if (priv->acpi_reserved) > return -EBUSY; > - } > > pm_runtime_get_sync(&priv->pci_dev->dev); > > @@ -919,7 +915,6 @@ static s32 i801_access(struct i2c_adapter *adap, u16 addr, > > pm_runtime_mark_last_busy(&priv->pci_dev->dev); > pm_runtime_put_autosuspend(&priv->pci_dev->dev); > - mutex_unlock(&priv->acpi_lock); > return ret; > } > > @@ -1571,7 +1566,7 @@ i801_acpi_io_handler(u32 function, acpi_physical_address address, u32 bits, > * further access from the driver itself. This device is now owned > * by the system firmware. > */ > - mutex_lock(&priv->acpi_lock); > + i2c_lock_bus(&priv->adapter, I2C_LOCK_SEGMENT); > > if (!priv->acpi_reserved && i801_acpi_is_smbus_ioport(priv, address)) { > priv->acpi_reserved = true; > @@ -1591,7 +1586,7 @@ i801_acpi_io_handler(u32 function, acpi_physical_address address, u32 bits, > else > status = acpi_os_write_port(address, (u32)*value, bits); > > - mutex_unlock(&priv->acpi_lock); > + i2c_unlock_bus(&priv->adapter, I2C_LOCK_SEGMENT); > > return status; > } > @@ -1651,7 +1646,6 @@ static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id) > priv->adapter.dev.parent = &dev->dev; > ACPI_COMPANION_SET(&priv->adapter.dev, ACPI_COMPANION(&dev->dev)); > priv->adapter.retries = 3; > - mutex_init(&priv->acpi_lock); > > priv->pci_dev = dev; > priv->features = id->driver_data; Reviewed-by: Jean Delvare <jdelvare@suse.de> Thanks,
Hi Heiner, On Wed, Sep 20, 2023 at 09:33:01AM +0200, Heiner Kallweit wrote: > I2C core ensures in i2c_smbus_xfer() that the I2C bus lock is held when > calling the smbus_xfer callback. That's i801_access() in our case. > I think it's safe in general to assume that the I2C bus lock is held > when the smbus_xfer callback is called. > Therefore I see no need to define an own mutex. > > Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Reviewed-by: Andi Shyti <andi.shyti@kernel.org> Andi
On Wed, Sep 20, 2023 at 09:33:01AM +0200, Heiner Kallweit wrote: > I2C core ensures in i2c_smbus_xfer() that the I2C bus lock is held when > calling the smbus_xfer callback. That's i801_access() in our case. > I think it's safe in general to assume that the I2C bus lock is held > when the smbus_xfer callback is called. > Therefore I see no need to define an own mutex. > > Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Applied to for-next, thanks!
diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c index 26f132277..a485dc84d 100644 --- a/drivers/i2c/busses/i2c-i801.c +++ b/drivers/i2c/busses/i2c-i801.c @@ -293,10 +293,9 @@ struct i801_priv { /* * If set to true the host controller registers are reserved for - * ACPI AML use. Protected by acpi_lock. + * ACPI AML use. */ bool acpi_reserved; - struct mutex acpi_lock; }; #define FEATURE_SMBUS_PEC BIT(0) @@ -874,11 +873,8 @@ static s32 i801_access(struct i2c_adapter *adap, u16 addr, int hwpec, ret; struct i801_priv *priv = i2c_get_adapdata(adap); - mutex_lock(&priv->acpi_lock); - if (priv->acpi_reserved) { - mutex_unlock(&priv->acpi_lock); + if (priv->acpi_reserved) return -EBUSY; - } pm_runtime_get_sync(&priv->pci_dev->dev); @@ -919,7 +915,6 @@ static s32 i801_access(struct i2c_adapter *adap, u16 addr, pm_runtime_mark_last_busy(&priv->pci_dev->dev); pm_runtime_put_autosuspend(&priv->pci_dev->dev); - mutex_unlock(&priv->acpi_lock); return ret; } @@ -1571,7 +1566,7 @@ i801_acpi_io_handler(u32 function, acpi_physical_address address, u32 bits, * further access from the driver itself. This device is now owned * by the system firmware. */ - mutex_lock(&priv->acpi_lock); + i2c_lock_bus(&priv->adapter, I2C_LOCK_SEGMENT); if (!priv->acpi_reserved && i801_acpi_is_smbus_ioport(priv, address)) { priv->acpi_reserved = true; @@ -1591,7 +1586,7 @@ i801_acpi_io_handler(u32 function, acpi_physical_address address, u32 bits, else status = acpi_os_write_port(address, (u32)*value, bits); - mutex_unlock(&priv->acpi_lock); + i2c_unlock_bus(&priv->adapter, I2C_LOCK_SEGMENT); return status; } @@ -1651,7 +1646,6 @@ static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id) priv->adapter.dev.parent = &dev->dev; ACPI_COMPANION_SET(&priv->adapter.dev, ACPI_COMPANION(&dev->dev)); priv->adapter.retries = 3; - mutex_init(&priv->acpi_lock); priv->pci_dev = dev; priv->features = id->driver_data;
I2C core ensures in i2c_smbus_xfer() that the I2C bus lock is held when calling the smbus_xfer callback. That's i801_access() in our case. I think it's safe in general to assume that the I2C bus lock is held when the smbus_xfer callback is called. Therefore I see no need to define an own mutex. Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> --- Patch was part of a broken-up previous series. --- drivers/i2c/busses/i2c-i801.c | 14 ++++---------- 1 file changed, 4 insertions(+), 10 deletions(-)