Messages in this thread | | | Subject | Re: [PATCH 1/2] HISI LPC: Reference static MFD cells for ACPI support | From | John Garry <> | Date | Fri, 4 May 2018 13:29:53 +0100 |
| |
On 03/05/2018 17:54, Andy Shevchenko wrote: > On Thu, 2018-05-03 at 23:08 +0800, John Garry wrote: >> Currently for ACPI support the driver models the host as >> an MFD. For a device connected to the LPC bus, we dynamically >> create an MFD cell for that device, configuring the cell >> name and ACPI match parameters manually. This makes supporting >> named devices and also special setup handling for certain devices >> awkward, as we would need to introduce some special ACPI device >> handling according to device HID. >> >> To avoid this, create reference static MFD cells for known >> child devices, so when adding an MFD cell we can fix the cell >> platform data as required. For this, a setup callback function >> is added.
Hi Andy,
>> >> For now, only the IPMI cell is added. > >> +static const struct mfd_cell *hisi_lpc_acpi_mfd_get_cell(const char >> *hid) >> +{ >> + const struct hisi_lpc_acpi_mfd_cell *cell = >> hisi_lpc_acpi_mfd_cells; >> + >> + for (; cell && cell->mfd_cell.name; cell++) { >> + const struct mfd_cell *mfd_cell = &cell->mfd_cell; >> + const struct mfd_cell_acpi_match *acpi_match; >> + >> + acpi_match = mfd_cell->acpi_match; >> + if (!strcmp(acpi_match->pnpid, hid)) >> + return mfd_cell; >> + } >> + >> + return NULL; >> +} > > I'm not sure I understand why MFD core can't do it (as seen in lines > drivers/mfd/core.c:105 and below). >
Right, I think MFD core does the same.
>> + /* allocate the mfd cells, one per child */ >> + size = sizeof(*mfd_cells); >> mfd_cells = devm_kcalloc(hostdev, cell_num, size, >> GFP_KERNEL); >> if (!mfd_cells) >> return -ENOMEM; > > And since you have structures already, I'm not sure why you need another > allocation for them. Only what you would need is to apply resources and > call devm_mfd_add_devices() per each found device.
I was creating a copy as the originals are in the hisi_lpc_acpi_mfd_cell struct type, while we would require an array of mfd_cells.
> >> + cell = container_of(mfd_cell_ref, typeof(*cell), >> mfd_cell); > > Why we can't iterate over inherited type of objects directly? >
We could do.
Thanks, John
| |