Re: [PATCH v2 1/1] platform/x86/intel_cht_int33fe: Split code to USB TypeB and TypeC variants

[Hans de Goede <hdegoede@redhat.com>]

Hi,

On 17-09-2019 21:45, Yauhen Kharuzhy wrote:
> Existing intel_cht_int33fe ACPI pseudo-device driver assumes that
> hardware has TypeC connector and register related devices described as
> I2C connections in the _CRS resource.
> 
> There is at least one hardware (Lenovo Yoga Book YB1-91L/F) with micro
> USB B connector exists. It has INT33FE device in the DSDT table but
> there are only two I2C connection described: PMIC and BQ27452 battery
> fuel gauge.
> 
> Splitting existing INT33FE driver allow to maintain code for USB type B
> (AB) connector variant separately and make it simpler.
> 
> Split driver to intel_cht_int33fe_common.c and
> intel_cht_int33fe_{typeb,typec}.c. Compile all this source to one .ko
> module to make user experience easier.
> 
> Signed-off-by: Yauhen Kharuzhy <jekhor@gmail.com>

Thank you for doing this, this version looks much better IMHO.

Note that this does not apply to Linus' current master, please
rebase. Specifically this conflicts with this patch:

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=78cd4bf53635d3aeb73435bc89eb6eb39450f315

Which just got merged. Instead of rebasing on Linus' master
(which is always a bit adventurous to use during the merge window)
you can also cherry-pick that single commit on top of v5.3
and use that as a base.

Note that that patch makes changes to struct cht_int33fe_data
specifically it drops the:

	struct fwnode_handle *mux;

Member, so when rebasing you should drop that in the new
version of the struct on common.h .

Besides that this need a rebase, overall this looks good, I have some
small remarks inline:

<snip>

> diff --git a/drivers/platform/x86/intel_cht_int33fe_common.c b/drivers/platform/x86/intel_cht_int33fe_common.c
> new file mode 100644
> index 000000000000..4a3d7ebd37dd
> --- /dev/null
> +++ b/drivers/platform/x86/intel_cht_int33fe_common.c
> @@ -0,0 +1,148 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Common code for Intel Cherry Trail ACPI INT33FE pseudo device drivers
> + * (USB TypeB and TypeC connector variants).
> + *
> + * Copyright (c) 2019 Yauhen Kharuzhy <jekhor@gmail.com>
> + */
> +
> +#include <linux/acpi.h>
> +#include <linux/i2c.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/slab.h>
> +
> +#include "intel_cht_int33fe_common.h"
> +
> +#define EXPECTED_PTYPE		4
> +
> +static int cht_int33fe_i2c_res_filter(struct acpi_resource *ares, void *data)
> +{
> +	struct acpi_resource_i2c_serialbus *sb;
> +	int *count = data;
> +
> +	if (i2c_acpi_get_i2c_resource(ares, &sb))
> +		(*count)++;
> +
> +	return 1;
> +}
> +
> +static int cht_int33fe_count_i2c_clients(struct device *dev)
> +{
> +	struct acpi_device *adev;
> +	LIST_HEAD(resource_list);
> +	int count = 0;
> +
> +	adev = ACPI_COMPANION(dev);
> +	if (!adev)
> +		return -EINVAL;
> +
> +	acpi_dev_get_resources(adev, &resource_list,
> +			       cht_int33fe_i2c_res_filter, &count);
> +
> +	acpi_dev_free_resource_list(&resource_list);
> +
> +	return count;
> +}
> +
> +static int cht_int33fe_check_hw_type(struct device *dev)
> +{
> +	unsigned long long ptyp;
> +	acpi_status status;
> +	int ret;
> +
> +	status = acpi_evaluate_integer(ACPI_HANDLE(dev), "PTYP", NULL, &ptyp);
> +	if (ACPI_FAILURE(status)) {
> +		dev_err(dev, "Error getting PTYPE\n");
> +		return -ENODEV;
> +	}
> +
> +	/*
> +	 * The same ACPI HID is used for different configurations check PTYP
> +	 * to ensure that we are dealing with the expected config.
> +	 */
> +	if (ptyp != EXPECTED_PTYPE)
> +		return -ENODEV;
> +
> +	/* Check presence of INT34D3 (hardware-rev 3) expected for ptype == 4 */
> +	if (!acpi_dev_present("INT34D3", "1", 3)) {
> +		dev_err(dev, "Error PTYPE == %d, but no INT34D3 device\n",
> +			EXPECTED_PTYPE);
> +		return -ENODEV;
> +	}
> +
> +	ret = cht_int33fe_count_i2c_clients(dev);
> +	if (ret < 0)
> +		return ret;
> +
> +	switch (ret) {
> +	case 2:
> +		return INT33FE_HW_TYPEB;
> +	case 4:
> +		return INT33FE_HW_TYPEC;
> +	default:
> +		return -ENODEV;
> +	}
> +}
> +
> +static int cht_int33fe_probe(struct platform_device *pdev)
> +{
> +	struct cht_int33fe_data *data;
> +	struct device *dev = &pdev->dev;
> +	int ret;
> +
> +	ret = cht_int33fe_check_hw_type(dev);
> +	if (ret < 0)
> +		return ret;
> +
> +	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
> +	if (!data)
> +		return -ENOMEM;
> +
> +	data->hw_type = ret;
> +	data->dev = dev;
> +
> +	switch (data->hw_type) {

I suggested adding hw_type to data so that it could be used to
select the right remove function in cht_int33fe_remove(),
since you are using a remove function pointer in data for this
(which is fine), there is no reason to store hw_type in
cht_int33fe_data anymore, please drop this and change the

	switch (data->hw_type) {

to:

	switch (ret) {


> +	case INT33FE_HW_TYPEB:
> +		data->probe = cht_int33fe_typeb_probe;
> +		data->remove = cht_int33fe_typeb_remove;
> +		break;
> +
> +	case INT33FE_HW_TYPEC:
> +		data->probe = cht_int33fe_typec_probe;
> +		data->remove = cht_int33fe_typec_remove;
> +		break;
> +	}
> +
> +	platform_set_drvdata(pdev, data);
> +
> +	return data->probe(data);
> +}
> +
> +static int cht_int33fe_remove(struct platform_device *pdev)
> +{
> +	struct cht_int33fe_data *data = platform_get_drvdata(pdev);
> +
> +	return data->remove(data);
> +}

<snip>

> diff --git a/drivers/platform/x86/intel_cht_int33fe_common.h b/drivers/platform/x86/intel_cht_int33fe_common.h
> new file mode 100644
> index 000000000000..cb0cc4552017
> --- /dev/null
> +++ b/drivers/platform/x86/intel_cht_int33fe_common.h
> @@ -0,0 +1,44 @@

<snip>

> +int cht_int33fe_typec_remove(struct cht_int33fe_data *data);
> +
> +#endif /* _INTEL_CHT_INT33FE_COMMON_H */
> +

Please drop the empty line at the end of intel_cht_int33fe_common.h .

> diff --git a/drivers/platform/x86/intel_cht_int33fe_typeb.c b/drivers/platform/x86/intel_cht_int33fe_typeb.c
> new file mode 100644
> index 000000000000..905c29f2f714
> --- /dev/null
> +++ b/drivers/platform/x86/intel_cht_int33fe_typeb.c
> @@ -0,0 +1,64 @@

<snip>

> +int cht_int33fe_typeb_remove(struct cht_int33fe_data *data)
> +{
> +	i2c_unregister_device(data->battery_fg);
> +
> +	return 0;
> +}
> +
> diff --git a/drivers/platform/x86/intel_cht_int33fe.c b/drivers/platform/x86/intel_cht_int33fe_typec.c

Please drop the empty line at the end of intel_cht_int33fe_typeb.c .

Regards,

Hans

p.s.

I've done the rebase myself and I'm building a kernel with my re-based version of this
patch to test it on a typec device. I will get back to you with the results
(I expect things will just work, just making sure).