| Message ID | TYCP286MB26079F414019C8AC9303E412B1E69@TYCP286MB2607.JPNP286.PROD.OUTLOOK.COM |
|---|---|
| State | New |
| Headers | show |
| Series | [v1] i2c: i2c-core-base: Modify the maximum idr id for i2c adapter | expand |
On Fri, Dec 16, 2022 at 10:07:51AM +0800, Riwen Lu wrote: > From: Riwen Lu <luriwen@kylinos.cn> > > Change the maximum idr ID to INT_MAX for i2c adapter. > This fix the following adding i2c adapter error while the idr with > adap->nr has been allocated by other i2c driver, and find a proper ID How did this happen that another i2c driver could get this? Were you able to follow the code paths that lead to this situation? > for it. > [ 357.620685][ 3] [ T3655] ------------[ cut here ]------------ > [ 357.626544][ 3] [ T3655] couldn't get idr > > Signed-off-by: Riwen Lu <luriwen@kylinos.cn> > --- > drivers/i2c/i2c-core-base.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c > index 7539b0740351..c2982861057a 100644 > --- a/drivers/i2c/i2c-core-base.c > +++ b/drivers/i2c/i2c-core-base.c > @@ -1535,11 +1535,12 @@ static int __i2c_add_numbered_adapter(struct i2c_adapter *adap) > int id; > > mutex_lock(&core_lock); > - id = idr_alloc(&i2c_adapter_idr, adap, adap->nr, adap->nr + 1, GFP_KERNEL); > + id = idr_alloc(&i2c_adapter_idr, adap, adap->nr, 0, GFP_KERNEL); > mutex_unlock(&core_lock); > if (WARN(id < 0, "couldn't get idr")) > return id == -ENOSPC ? -EBUSY : id; > > + adap->nr = id; > return i2c_register_adapter(adap); > } > > -- > 2.25.1 >
在 2023/1/9 23:13, Wolfram Sang 写道: > On Fri, Dec 16, 2022 at 10:07:51AM +0800, Riwen Lu wrote: >> From: Riwen Lu <luriwen@kylinos.cn> >> >> Change the maximum idr ID to INT_MAX for i2c adapter. >> This fix the following adding i2c adapter error while the idr with >> adap->nr has been allocated by other i2c driver, and find a proper ID > > How did this happen that another i2c driver could get this? Were you > able to follow the code paths that lead to this situation? > Yes, it's happened in Phytium(Arm64) platform with MWV207 GPU. 1. The MWV207 GPU driver has registered I2C adapter, and allocated idr id 0-6 with i2c_adapter_idr. # cd /sys/class/i2c-adapter/i2c-0/ # ls i2c-0 i2c-1 i2c-2 i2c-3 i2c-4 i2c-5 i2c-6 # cd i2c-0/ # ls delete_device device i2c-dev name new_device power subsystem uevent # cat name MWV207_I2C_0 2. The BIOS's ACPI DSDT has declared I2C device with _UID 0 as following: Device (I2C0) { Name (_HID, "PHYT0038") // _HID: Hardware ID Name (_UID, Zero) // _UID: Unique ID Name (_CRS, ResourceTemplate () { Memory32Fixed (ReadWrite, 0x28014000, 0x00001000, ) Interrupt (ResourceConsumer, Level, ActiveHigh, Exclusive, ,, ) { 0x0000007C, } }) ... } The Phytium i2c driver would register the i2c adapter with idr id 0 by calling function i2c_add_numbered_adapter(adap). Then, function idr_alloc(&i2c_adapter_idr, adap, adap->nr, adap->nr + 1, GFP_KERNEL)； allocate the idr failed because idr id adap->nr(It equal to _UID) has been allocated by MWV207 GPU, and print the following error: couldn't get idr i2c-phytium-platform PHYT0038:00: fail to add adapter: -16 This patch can solve the problem. >> for it. >> [ 357.620685][ 3] [ T3655] ------------[ cut here ]------------ >> [ 357.626544][ 3] [ T3655] couldn't get idr >> >> Signed-off-by: Riwen Lu <luriwen@kylinos.cn> >> --- >> drivers/i2c/i2c-core-base.c | 3 ++- >> 1 file changed, 2 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c >> index 7539b0740351..c2982861057a 100644 >> --- a/drivers/i2c/i2c-core-base.c >> +++ b/drivers/i2c/i2c-core-base.c >> @@ -1535,11 +1535,12 @@ static int __i2c_add_numbered_adapter(struct i2c_adapter *adap) >> int id; >> >> mutex_lock(&core_lock); >> - id = idr_alloc(&i2c_adapter_idr, adap, adap->nr, adap->nr + 1, GFP_KERNEL); >> + id = idr_alloc(&i2c_adapter_idr, adap, adap->nr, 0, GFP_KERNEL); >> mutex_unlock(&core_lock); >> if (WARN(id < 0, "couldn't get idr")) >> return id == -ENOSPC ? -EBUSY : id; >> >> + adap->nr = id; >> return i2c_register_adapter(adap); >> } >> >> -- >> 2.25.1 >>
> The Phytium i2c driver would register the i2c adapter with idr id 0 by > calling function i2c_add_numbered_adapter(adap). Then, function > idr_alloc(&i2c_adapter_idr, adap, adap->nr, adap->nr + 1, GFP_KERNEL)； > allocate the idr failed because idr id adap->nr(It equal to _UID) has been > allocated by MWV207 GPU, and print the following error: > > couldn't get idr > i2c-phytium-platform PHYT0038:00: fail to add adapter: -16 i2c-phytium-platform is not an upstream driver, right? Why does it not simply use i2c_add_adapter() instead of i2c_add_numbered_adapter()?
diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c index 7539b0740351..c2982861057a 100644 --- a/drivers/i2c/i2c-core-base.c +++ b/drivers/i2c/i2c-core-base.c @@ -1535,11 +1535,12 @@ static int __i2c_add_numbered_adapter(struct i2c_adapter *adap) int id; mutex_lock(&core_lock); - id = idr_alloc(&i2c_adapter_idr, adap, adap->nr, adap->nr + 1, GFP_KERNEL); + id = idr_alloc(&i2c_adapter_idr, adap, adap->nr, 0, GFP_KERNEL); mutex_unlock(&core_lock); if (WARN(id < 0, "couldn't get idr")) return id == -ENOSPC ? -EBUSY : id; + adap->nr = id; return i2c_register_adapter(adap); }