lkml.org 
[lkml]   [2014]   [Nov]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v3 3/3] ACPI / PMIC: AXP288: support virtual GPIO in ACPI table
On 11/24/2014 09:06 AM, Rafael J. Wysocki wrote:
> On Friday, November 21, 2014 03:11:51 PM Aaron Lu wrote:
>> The same virtual GPIO strategy is also used for the AXP288 PMIC in that
>> various control methods that are used to do power rail handling and
>> sensor reading/setting will touch GPIO fields defined under the PMIC
>> device. The GPIO fileds are only defined by the ACPI code while the
>> actual hardware doesn't really have a GPIO controller, but to make those
>> control method execution succeed, we have to install a GPIO handler for
>> the PMIC device handle. Since we do not need the virtual GPIO strategy,
>> we can simply do nothing in that handler.
>>
>> Signed-off-by: Aaron Lu <aaron.lu@intel.com>
>> ---
>> drivers/acpi/pmic/intel_pmic_xpower.c | 27 +++++++++++++++++++++++----
>> 1 file changed, 23 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/acpi/pmic/intel_pmic_xpower.c b/drivers/acpi/pmic/intel_pmic_xpower.c
>> index 6c4d6ce0cff1..480c41c36444 100644
>> --- a/drivers/acpi/pmic/intel_pmic_xpower.c
>> +++ b/drivers/acpi/pmic/intel_pmic_xpower.c
>> @@ -251,13 +251,32 @@ static struct intel_pmic_opregion_data intel_xpower_pmic_opregion_data = {
>> .thermal_table_count = ARRAY_SIZE(thermal_table),
>> };
>>
>> +static acpi_status intel_xpower_pmic_gpio_handler(u32 function,
>> + acpi_physical_address address, u32 bit_width, u64 *value,
>> + void *handler_context, void *region_context)
>> +{
>> + return AE_OK;
>> +}
>>
>> static int intel_xpower_pmic_opregion_probe(struct platform_device *pdev)
>> {
>> - struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent);
>> - return intel_pmic_install_opregion_handler(&pdev->dev,
>> - ACPI_HANDLE(pdev->dev.parent), axp20x->regmap,
>> - &intel_xpower_pmic_opregion_data);
>> + struct device *parent = pdev->dev.parent;
>> + struct axp20x_dev *axp20x = dev_get_drvdata(parent);
>> + acpi_status status;
>> + int result;
>> +
>> + result = intel_pmic_install_opregion_handler(&pdev->dev,
>> + ACPI_HANDLE(parent), axp20x->regmap,
>> + &intel_xpower_pmic_opregion_data);
>> + if (!result) {
>> + status = acpi_install_address_space_handler(
>> + ACPI_HANDLE(parent), ACPI_ADR_SPACE_GPIO,
>> + intel_xpower_pmic_gpio_handler, NULL, NULL);
>
> So here we have a problem, because we can't unregister the opregion handler
> registered above if this fails. Not nice.

I'll add a remove_opregion_handler call if the above install failed, the
chance the remove_opregion_handler will trigger a problem during init time
is pretty low.

If that is not desired, I can install the operation region handler for
the virtual GPIO first and then the real PMIC operation region handler,
the cost of leaving a virtual GPIO operation region handler is essential
zero I think.

Thanks,
Aaron

>
>> + if (ACPI_FAILURE(status))
>> + result = -ENODEV;
>> + }
>> +
>> + return result;
>> }
>>
>> static struct platform_driver intel_xpower_pmic_opregion_driver = {
>>
>



\
 
 \ /
  Last update: 2014-11-24 08:01    [W:0.121 / U:2.616 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site