Hi Laurent

On 23/02/2021 20:04, Laurent Pinchart wrote:

+
+/*
+ * Here follows platform specific mapping information that we can pass to
+ * the functions mapping resources to the sensors. Where the sensors have
+ * a power enable pin defined in DSDT we need to provide a supply name so
+ * the sensor drivers can find the regulator. The device name will be derived
+ * from the sensor's ACPI device within the code. Optionally, we can provide a
+ * NULL terminated array of function name mappings to deal with any platform
+ * specific deviations from the documented behaviour of GPIOs.
+ *
+ * Map a GPIO function name to NULL to prevent the driver from mapping that
+ * GPIO at all.
+ */
+
+static const struct int3472_gpio_function_remap ov2680_gpio_function_remaps[] = {
+	{ "reset", NULL },
+	{ "powerdown", "reset" },
+	{ }
+};
+
+static struct int3472_sensor_config int3472_sensor_configs[] = {
This should be static const (and there will be some fallout due to that,
as skl_int3472_register_regulator() modifies the supply_map, so I think
you'll have a copy of supply_map in int3472_discrete_device).

Ack to all of the constness; you mentioned that last time too - not sure
how I missed doing those! I think I can just having a local struct
regulator_consumer_supply in skl_int3472_register_regulator and fill it
from int3472->sensor_config.supply_map

quoted

+static unsigned int skl_int3472_get_clk_frequency(struct int3472_discrete_device *int3472)
+{
+	union acpi_object *obj;
+	unsigned int ret = 0;
+
+	obj = skl_int3472_get_acpi_buffer(int3472->sensor, "SSDB");
+	if (IS_ERR(obj))
+		return 0; /* report rate as 0 on error */
+
+	if (obj->buffer.length < CIO2_SENSOR_SSDB_MCLKSPEED_OFFSET + sizeof(u32)) {

Should we define an ssdb structure instead of peeking into the buffer
with an offset ?

I thought about that, but in the end decided it didn't seem worth
defining the whole SSDB structure just to use one field. Particularly
since we use it in cio2-bridge already, so if we're going to do that it
really ought to just live in a header that's included in both - and that
seemed even less worthwhile.


I don't have a strong feeling though, so if you think it's better to
define the struct I'm happy to.

quoted

+static unsigned long skl_int3472_clk_recalc_rate(struct clk_hw *hw,
+						 unsigned long parent_rate)
+{
+	struct int3472_gpio_clock *clk = to_int3472_clk(hw);
+	struct int3472_discrete_device *int3472 = to_int3472_device(clk);
+
+	return int3472->clock.frequency;

Maybe just

	struct int3472_gpio_clock *clk = to_int3472_clk(hw);

	return clk->frequency;

Oops, of course.

quoted

+static int skl_int3472_register_regulator(struct int3472_discrete_device *int3472,
+					  struct acpi_resource *ares)
+{
+	char *path = ares->data.gpio.resource_source.string_ptr;
+	struct int3472_sensor_config *sensor_config;
+	struct regulator_init_data init_data = { };
+	struct regulator_config cfg = { };
+	int ret;
+
+	sensor_config = int3472->sensor_config;
+	if (IS_ERR_OR_NULL(sensor_config)) {
+		dev_err(int3472->dev, "No sensor module config\n");
+		return PTR_ERR(sensor_config);
+	}
+
+	if (!sensor_config->supply_map.supply) {
+		dev_err(int3472->dev, "No supply name defined\n");
+		return -ENODEV;
+	}
+
+	init_data.constraints.valid_ops_mask = REGULATOR_CHANGE_STATUS;
+	init_data.num_consumer_supplies = 1;
+	sensor_config->supply_map.dev_name = int3472->sensor_name;
+	init_data.consumer_supplies = &sensor_config->supply_map;
+
+	snprintf(int3472->regulator.regulator_name,
+		 sizeof(int3472->regulator.regulator_name), "%s-regulator",
+		 acpi_dev_name(int3472->adev));
+	snprintf(int3472->regulator.supply_name,
+		 GPIO_REGULATOR_SUPPLY_NAME_LENGTH, "supply-0");
+
+	int3472->regulator.rdesc = INT3472_REGULATOR(
+						int3472->regulator.regulator_name,
+						int3472->regulator.supply_name,
+						&int3472_gpio_regulator_ops);
+
+	int3472->regulator.gpio = acpi_get_gpiod(path,
+						 ares->data.gpio.pin_table[0],
+						 "int3472,regulator");
+	if (IS_ERR(int3472->regulator.gpio)) {
+		dev_err(int3472->dev, "Failed to get regulator GPIO lines\n");

s/lines/line/ (sorry, it was a typo in my review of v2)

No problem!

quoted

+static int skl_int3472_parse_crs(struct int3472_discrete_device *int3472)
+{
+	struct list_head resource_list;
+	int ret;
+
+	INIT_LIST_HEAD(&resource_list);
+
+	int3472->sensor_config = skl_int3472_get_sensor_module_config(int3472);

I have forgotten some of the context I'm afraid :-/ Are there valid use
cases for not checking for an error here, or should we do so and drop
the error checks in other functions above ?

Not all platforms need a sensor_config; only those which have either a
regulator pin or need a GPIO function to be remapped; the rest will do
without it.

So, we need to not check for an error here because the absence of a
sensor_config isn't necessarily an error, we won't know till later.

+int skl_int3472_discrete_probe(struct platform_device *pdev)
+{
+	struct acpi_device *adev = ACPI_COMPANION(&pdev->dev);
+	struct int3472_discrete_device *int3472;
+	struct int3472_cldb cldb;
+	int ret;
+
+	ret = skl_int3472_fill_cldb(adev, &cldb);
+	if (ret) {
+		dev_err(&pdev->dev, "Couldn't fill CLDB structure\n");
+		return ret;
+	}
+
+	if (cldb.control_logic_type != 1) {
+		dev_err(&pdev->dev, "Unsupported control logic type %u\n",
+			cldb.control_logic_type);
+		return -EINVAL;
+	}
+
+	/* Max num GPIOs we've seen plus a terminator */
+	int3472 = kzalloc(struct_size(int3472, gpios.table,
+			  INT3472_MAX_SENSOR_GPIOS + 1), GFP_KERNEL);
+	if (!int3472)
+		return -ENOMEM;
+
+	int3472->adev = adev;
+	int3472->dev = &pdev->dev;
+	platform_set_drvdata(pdev, int3472);
+
+	int3472->sensor = acpi_dev_get_dependent_dev(adev);
+	if (IS_ERR_OR_NULL(int3472->sensor)) {
+		dev_err(&pdev->dev,
+			"INT3472 seems to have no dependents.\n");
+		ret = -ENODEV;
+		goto err_free_int3472;
+	}
+	get_device(&int3472->sensor->dev);
I see no corresponding put_device(), am I missing something ? I'm also
not sure why this is needed.

The put is acpi_dev_put() in skl_int3472_discrete_remove(); there seems
to be no acpi_dev_get() for some reason. We use the sensor acpi_device
to get the clock frequency, and to fetch the sensor module string, so I
thought it ought to hold a reference on those grounds.

quoted

diff --git a/drivers/platform/x86/intel-int3472/intel_skl_int3472_tps68470.c b/drivers/platform/x86/intel-int3472/intel_skl_int3472_tps68470.c
new file mode 100644
index 000000000000..d0d2391e263f
--- /dev/null
+++ b/drivers/platform/x86/intel-int3472/intel_skl_int3472_tps68470.c

@@ -0,0 +1,113 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Author: Dan Scally <djrscally@gmail.com> */
+
+#include <linux/i2c.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/tps68470.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+#include "intel_skl_int3472_common.h"
+
+static const struct mfd_cell tps68470_c[] = {
+	{ .name = "tps68470-gpio" },
+	{ .name = "tps68470_pmic_opregion" },
+};
+
+static const struct mfd_cell tps68470_w[] = {

Maybe more explicit names than _c and _w could be nice ?

_chrome and _windows was in my mind - sound ok?