Re: [PATCH] of/irq: introduce of_has_named_irqs helper
From: Dmitry Torokhov
Date: Tue Jul 28 2015 - 14:07:34 EST
On Tue, Jul 28, 2015 at 11:16:44PM +0530, R, Vignesh wrote:
> Hi,
>
> On 7/28/2015 10:53 PM, Dmitry Torokhov wrote:
> > On Tue, Jul 28, 2015 at 06:53:52PM +0530, Vignesh R wrote:
> >> Hi Dmitry,
> >>
> >> On 07/25/2015 01:46 AM, Dmitry Torokhov wrote:
> >>> On Fri, Jul 24, 2015 at 12:26:19PM -0700, Dmitry Torokhov wrote:
> >>>> On Fri, Jul 24, 2015 at 02:14:57PM -0500, Rob Herring wrote:
> >>>>> On Fri, Jul 24, 2015 at 1:26 PM, Dmitry Torokhov
> >>>>> <dmitry.torokhov@xxxxxxxxx> wrote:
> >>>>>> Sometimes drivers might wish to transition from index-based to named
> >>>>>> interrupt descriptions. To aid in decision-making when parsing device
> >>>>>> tree data let's provide a helper that will indicate the scheme that is
> >>>>>> being used.
> >>>>>
> >>>>> Generally, IRQs are retrieved by platform_get_irq or
> >>>>> platform_get_irq_byname. Drivers should not call the of_irq_*
> >>>>> functions directly in most cases.
> >>>>
> >>>> That would be true for platform drivers, but not all devices are
> >>>> platform devices.
> >>>>
> >>>>>
> >>>>>>
> >>>>>> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
> >>>>>> ---
> >>>>>>
> >>>>>> The intent is to it like this:
> >>>>>>
> >>>>>> if (of_has_named_irqs(np) {
> >>>>>> /* Wake IRQ is optional */
> >>>>>> dev->wakeirq = of_irq_get_byname(np, "wakeup");
> >>>>>> if (dev->wakeirq < 0 && dev->wakeirq != -ENODATA)
> >>>>>> return dev->wakeirq;
> >>>>>> }
> >>>>>
> >>>>> of_irq_get_byname will already return an error if the property is not
> >>>>> present. Use that.
> >>>>
> >>>> I do not like that it returns -EINVAL when property is missing, can we
> >>>> change it to return -ENODATA (so it is the same as when the property is
> >>>> defined but such name is missing)?
> >>>
> >>> So here is what I had in mind.. It is based on recent patch by Vignesh
> >>> for pixcir touchscreen, but I think it should be made available to all
> >>> I2C devices. Completely untested at the moment.
> >>>
> >>
> >> Thanks for the patch! I tested this on am437x-gp-evm and the
> >> suspend/resume worked fine (below patch + $subject patch). I was able to
> >> wake the system from low power state using touchscreen. Also verified
> >> module insertion and removal. One comment though, please see below.
> >>
> >>> ---
> >>> drivers/i2c/i2c-core.c | 43 +++++++++++++++++++++++++++++++++++++------
> >>> 1 file changed, 37 insertions(+), 6 deletions(-)
> >>>
> >>> diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
> >>> index e6d4935..3971461 100644
> >>> --- a/drivers/i2c/i2c-core.c
> >>> +++ b/drivers/i2c/i2c-core.c
> >>> @@ -47,6 +47,7 @@
> >>> #include <linux/rwsem.h>
> >>> #include <linux/pm_runtime.h>
> >>> #include <linux/pm_domain.h>
> >>> +#include <linux/pm_wakeirq.h>
> >>> #include <linux/acpi.h>
> >>> #include <linux/jump_label.h>
> >>> #include <asm/uaccess.h>
> >>> @@ -631,6 +632,7 @@ static int i2c_device_probe(struct device *dev)
> >>> {
> >>> struct i2c_client *client = i2c_verify_client(dev);
> >>> struct i2c_driver *driver;
> >>> + int wakeirq = 0;
> >>> int status;
> >>>
> >>> if (!client)
> >>> @@ -639,11 +641,13 @@ static int i2c_device_probe(struct device *dev)
> >>> if (!client->irq) {
> >>> int irq = -ENOENT;
> >>>
> >>> - if (dev->of_node)
> >>> - irq = of_irq_get(dev->of_node, 0);
> >>> - else if (ACPI_COMPANION(dev))
> >>> + if (dev->of_node) {
> >>> + irq = of_has_named_irqs(dev->of_node) ?
> >>> + of_irq_get_byname(dev->of_node, "irq") :
> >>> + of_irq_get(dev->of_node, 0);
> >>> + } else if (ACPI_COMPANION(dev)) {
> >>> irq = acpi_dev_gpio_irq_get(ACPI_COMPANION(dev), 0);
> >>> -
> >>> + }
> >>> if (irq == -EPROBE_DEFER)
> >>> return irq;
> >>> if (irq < 0)
> >>> @@ -652,6 +656,15 @@ static int i2c_device_probe(struct device *dev)
> >>> client->irq = irq;
> >>> }
> >>>
> >>> + if (dev->of_node && of_has_named_irqs(dev->of_node)) {
> >>> + wakeirq = of_irq_get_byname(dev->of_node, "wakeup");
> >>> + if (wakeirq < 0) {
> >>> + if (wakeirq != -ENODATA)
> >>> + return wakeirq;
> >>> + wakeirq = 0;
> >>> + }
> >>> + }
> >>> +
> >>> driver = to_i2c_driver(dev->driver);
> >>> if (!driver->probe || !driver->id_table)
> >>> return -ENODEV;diff --git a/drivers/input/touchscreen/pixcir_i2c_ts.c b/drivers/input/touchscreen/pixcir_i2c_ts.c
> index 8f3e243a62bf..6bd1d1ca9883 100644
> --- a/drivers/input/touchscreen/pixcir_i2c_ts.c
> +++ b/drivers/input/touchscreen/pixcir_i2c_ts.c
> @@ -365,7 +365,6 @@ static int __maybe_unused
> pixcir_i2c_ts_suspend(struct device *dev)
> }
> }
>
> - enable_irq_wake(client->irq);
> } else if (input->users) {
> ret = pixcir_stop(ts);
> }
> @@ -386,7 +385,6 @@ static int __maybe_unused
> pixcir_i2c_ts_resume(struct device *dev)
> mutex_lock(&input->mutex);
>
> if (device_may_wakeup(&client->dev)) {
> - disable_irq_wake(client->irq);
>
> if (!input->users) {
> ret = pixcir_stop(ts);
> @@ -464,7 +462,7 @@ static int pixcir_i2c_ts_probe(struct i2c_client
> *client,
> struct pixcir_i2c_ts_data *tsdata;
> struct input_dev *input;
> int error;
> -
> +printk("PROBING PIXCIR\n");
> if (np && !pdata) {
> pdata = pixcir_parse_dt(dev);
> if (IS_ERR(pdata))
> @@ -562,14 +560,6 @@ static int pixcir_i2c_ts_probe(struct i2c_client
> *client,
> return error;
>
> i2c_set_clientdata(client, tsdata);
> - device_init_wakeup(&client->dev, 1);
> -
> - return 0;
> -}
> -
> -static int pixcir_i2c_ts_remove(struct i2c_client *client)
> -{
> - device_init_wakeup(&client->dev, 0);
>
> return 0;
> }
> @@ -608,7 +598,6 @@ static struct i2c_driver pixcir_i2c_ts_driver = {
> .of_match_table = of_match_ptr(pixcir_of_match),
> },
> .probe = pixcir_i2c_ts_probe,
> - .remove = pixcir_i2c_ts_remove,
> .id_table = pixcir_i2c_ts_id,
> };
> >>> @@ -659,20 +672,34 @@ static int i2c_device_probe(struct device *dev)
> >>> if y i2c(!device_can_wakeup(&client->dev))
> >>> device_init_wakeup(&client->dev,
> >>> client->flags & I2C_CLIENT_WAKE);
> >>> +
> >>> + status = wakeirq > 0 ?
> >>> + dev_pm_set_dedicated_wake_irq(dev, wakeirq) :
> >>> + (client->irq > 0 ?
> >>> + dev_pm_set_wake_irq(dev, client->irq) : 0);
> >>
> >> Above code tries to register wakeirq irrespective of whether the device
> >> is specified as wakeup-source in the dt or not. Hence, I see warn
> >> messages from every i2c device that has irq line but hasn't declared
> >> itself as wakeup-source:
> >> For example tps is on i2c:
> >> [ 1.961613] tps65218 0-0024: forgot to call call device_init_wakeup?
> >> [ 1.968340] tps65218 0-0024: failed to set up wakeup irq
> >>
> >> May be you can register wakeup-source only if I2C_CLIENT_WAKE flag is
> >> set in client->flags?
> >
> > Makes sense, I'll prepare a new version.
> >
> > Just to confirm: do you see any issues with these 2 patches if you do
> > not modify the drivers to drop calls enable_irq_wake() from them?
>
> No, I didn't test w/o dropping enable_irq_wake() calls. I will do that
> tomo. Is this to verify that these 2 patches can be added w/o dropping
> enable_irq_wake() from other i2c drivers currently using them?
Yes.
Thanks.
--
Dmitry
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