| Message ID | 20240815-ad7606_add_iio_backend_support-v1-5-cea3e11b1aa4@baylibre.com |
|---|---|
| State | New |
| Headers | show |
| Series | Add iio backend compatibility for ad7606 | expand |
On Thu, 15 Aug 2024 12:11:59 +0000 Guillaume Stols <gstols@baylibre.com> wrote: > Inspired from spi_get_device_match_data() helper: if OF or ACPI driver > data is available, platform_get_device_id will return NULL because > platform_match_id is not called, and pdev->id_entry is never populated. > This helper function checks if match data is available, and otherwise > returns the ID table data. Likely no one will read the patch description but for these it's worth some scary text to point out that the driver_data must be a pointer. If people use an enum we need to do a dance to avoid the value 0. We get quite a few buggy conversions of i2c/spi drivers as a result of that little gotcha. Otherwise this seems like a sensible addition to me. Potentially worth pulling out as a precursor series with a few examples of how it saves on repeating this same code block in a bunch of existing drivers. Up to GregKH I think for how he'd like this (assuming he approves!) Jonathan > > Signed-off-by: Guillaume Stols <gstols@baylibre.com> > --- > drivers/base/platform.c | 12 ++++++++++++ > include/linux/platform_device.h | 1 + > 2 files changed, 13 insertions(+) > > diff --git a/drivers/base/platform.c b/drivers/base/platform.c > index 4c3ee6521ba5..26e9a026eb05 100644 > --- a/drivers/base/platform.c > +++ b/drivers/base/platform.c > @@ -1090,6 +1090,18 @@ static const struct platform_device_id *platform_match_id( > return NULL; > } > > +const void *platform_get_device_match_data(const struct platform_device *pdev) > +{ > + const struct platform_device_id *match; > + > + match = device_get_match_data(&pdev->dev); > + if (match) > + return match; > + > + return (const void *)platform_get_device_id(pdev)->driver_data; > +} > +EXPORT_SYMBOL_GPL(platform_get_device_match_data); > + > #ifdef CONFIG_PM_SLEEP > > static int platform_legacy_suspend(struct device *dev, pm_message_t mesg) > diff --git a/include/linux/platform_device.h b/include/linux/platform_device.h > index d422db6eec63..e2cc09ecc447 100644 > --- a/include/linux/platform_device.h > +++ b/include/linux/platform_device.h > @@ -45,6 +45,7 @@ struct platform_device { > }; > > #define platform_get_device_id(pdev) ((pdev)->id_entry) > +extern const void *platform_get_device_match_data(const struct platform_device *pdev); > > #define dev_is_platform(dev) ((dev)->bus == &platform_bus_type) > #define to_platform_device(x) container_of((x), struct platform_device, dev) >
diff --git a/drivers/base/platform.c b/drivers/base/platform.c index 4c3ee6521ba5..26e9a026eb05 100644 --- a/drivers/base/platform.c +++ b/drivers/base/platform.c @@ -1090,6 +1090,18 @@ static const struct platform_device_id *platform_match_id( return NULL; } +const void *platform_get_device_match_data(const struct platform_device *pdev) +{ + const struct platform_device_id *match; + + match = device_get_match_data(&pdev->dev); + if (match) + return match; + + return (const void *)platform_get_device_id(pdev)->driver_data; +} +EXPORT_SYMBOL_GPL(platform_get_device_match_data); + #ifdef CONFIG_PM_SLEEP static int platform_legacy_suspend(struct device *dev, pm_message_t mesg) diff --git a/include/linux/platform_device.h b/include/linux/platform_device.h index d422db6eec63..e2cc09ecc447 100644 --- a/include/linux/platform_device.h +++ b/include/linux/platform_device.h @@ -45,6 +45,7 @@ struct platform_device { }; #define platform_get_device_id(pdev) ((pdev)->id_entry) +extern const void *platform_get_device_match_data(const struct platform_device *pdev); #define dev_is_platform(dev) ((dev)->bus == &platform_bus_type) #define to_platform_device(x) container_of((x), struct platform_device, dev)
Inspired from spi_get_device_match_data() helper: if OF or ACPI driver data is available, platform_get_device_id will return NULL because platform_match_id is not called, and pdev->id_entry is never populated. This helper function checks if match data is available, and otherwise returns the ID table data. Signed-off-by: Guillaume Stols <gstols@baylibre.com> --- drivers/base/platform.c | 12 ++++++++++++ include/linux/platform_device.h | 1 + 2 files changed, 13 insertions(+)