On Fri, 07 Jun 2019, Ard Biesheuvel wrote:
> On Fri, 7 Jun 2019 at 10:29, Lee Jones <lee.jones@xxxxxxxxxx> wrote:
> >
> > Add a match table to allow automatic probing of ACPI device
> > QCOM0220. Ignore clock attainment errors. Set default clock
> > frequency value.
> >
> > Signed-off-by: Lee Jones <lee.jones@xxxxxxxxxx>
> > ---
> > drivers/i2c/busses/i2c-qcom-geni.c | 19 +++++++++++++++++--
> > 1 file changed, 17 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c
> > index db075bc0d952..0fa93b448e8d 100644
> > --- a/drivers/i2c/busses/i2c-qcom-geni.c
> > +++ b/drivers/i2c/busses/i2c-qcom-geni.c
> > @@ -1,6 +1,7 @@
> > // SPDX-License-Identifier: GPL-2.0
> > // Copyright (c) 2017-2018, The Linux Foundation. All rights reserved.
> >
> > +#include <linux/acpi.h>
> > #include <linux/clk.h>
> > #include <linux/dma-mapping.h>
> > #include <linux/err.h>
> > @@ -483,6 +484,12 @@ static const struct i2c_algorithm geni_i2c_algo = {
> > .functionality = geni_i2c_func,
> > };
> >
> > +static const struct acpi_device_id geni_i2c_acpi_match[] = {
> > + { "QCOM0220"},
> > + { },
> > +};
> > +MODULE_DEVICE_TABLE(acpi, geni_i2c_acpi_match);
> > +
>
> We usually put #ifdef CONFIG_ACPI/#endif around these, otherwise you
> end up with acpi:XXXX modaliases even though ACPI is not compiled in.
No problem.
> > static int geni_i2c_probe(struct platform_device *pdev)
> > {
> > struct geni_i2c_dev *gi2c;
> > @@ -502,7 +509,7 @@ static int geni_i2c_probe(struct platform_device *pdev)
> > return PTR_ERR(gi2c->se.base);
> >
> > gi2c->se.clk = devm_clk_get(&pdev->dev, "se");
>
> Can we avoid this call altogether in ACPI mode? Also, please use
I'm trying not to place all non-ACPI specific callers into if ()
statements. The tabbing becomes ridiculous in some places. A great
deal of these calls are requesting optional resources too, so it's
better to simply ignore the returning error in the cases where
non-optional resources (such as this one) are requested, since it has
the least impact on the existing code.
> 'has_acpi_companion()' to test whether we are probing via ACPI.
Sure.
> > - if (IS_ERR(gi2c->se.clk)) {
> > + if (IS_ERR(gi2c->se.clk) && !ACPI_HANDLE(&pdev->dev)) {
>
>
> > ret = PTR_ERR(gi2c->se.clk);
> > dev_err(&pdev->dev, "Err getting SE Core clk %d\n", ret);
> > return ret;
> > @@ -510,12 +517,19 @@ static int geni_i2c_probe(struct platform_device *pdev)
> >
> > ret = device_property_read_u32(&pdev->dev, "clock-frequency",
> > &gi2c->clk_freq_out);
> > - if (ret) {
> > + if (ret && !ACPI_HANDLE(&pdev->dev)) {
> > dev_info(&pdev->dev,
> > "Bus frequency not specified, default to 100kHz.\n");
> > gi2c->clk_freq_out = KHZ(100);
> > }
> >
> > + if (ACPI_HANDLE(&pdev->dev)) {
> > + ACPI_COMPANION_SET(&gi2c->adap.dev, ACPI_COMPANION(&pdev->dev));
> > +
> > + /* Using default, same as the !ACPI case above */
> > + gi2c->clk_freq_out = KHZ(100);
> > + }
> > +
>
> You are overriding the speed to 100 kHz even if the ACPI device has a
> "clock-frequency" property.
Will look at this.
Thanks Ard.
--
Lee Jones [李琼斯]
Linaro Services Technical Lead
Linaro.org │ Open source software for ARM SoCs
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