Hi Daniel,

Thank you for the patch.

On Mon, Feb 22, 2021 at 01:07:34PM +0000, Daniel Scally wrote:

Maybe these could be sorted alphabetically ?

Alphabetical order ?

+
+struct int3472_cldb {
+	u8 version;
+	/*
+	 * control logic type
+	 * 0: UNKNOWN
+	 * 1: DISCRETE(CRD-D)
+	 * 2: PMIC TPS68470
+	 * 3: PMIC uP6641
+	 */
+	u8 control_logic_type;
+	u8 control_logic_id;
+	u8 sensor_card_sku;
+	u8 reserved[28];
+};
+
+struct int3472_gpio_function_remap {
+	char *documented;
+	char *actual;

const char for both ?

+};
+
+struct int3472_sensor_config {
+	const char *sensor_module_name;
+	struct regulator_consumer_supply supply_map;
+	const struct int3472_gpio_function_remap *function_maps;
+};
+
+struct int3472_discrete_device {
+	struct acpi_device *adev;
+	struct device *dev;
+	struct acpi_device *sensor;
+	const char *sensor_name;
+
+	struct int3472_sensor_config *sensor_config;

const

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).

+	/* Lenovo Miix 510-12ISK - OV2680, Front */
+	{ "GNDF140809R", { 0 }, ov2680_gpio_function_remaps},

Missing space before } (and below too).

+	/* Lenovo Miix 510-12ISK - OV5648, Rear */
+	{ "GEFF150023R", REGULATOR_SUPPLY("avdd", NULL), NULL},
+	/* Surface Go 1&2 - OV5693, Front */
+	{ "YHCU", REGULATOR_SUPPLY("avdd", NULL), NULL},
+};
+
+/*
+ * The regulators have to have .ops to be valid, but the only ops we actually
+ * support are .enable and .disable which are handled via .ena_gpiod. Pass an
+ * empty struct to clear the check without lying about capabilities.
+ */
+static const struct regulator_ops int3472_gpio_regulator_ops = { 0 };
+
+static int skl_int3472_clk_prepare(struct clk_hw *hw)
+{
+	struct int3472_gpio_clock *clk = to_int3472_clk(hw);
+
+	gpiod_set_value(clk->ena_gpio, 1);
+	if (clk->led_gpio)
+		gpiod_set_value(clk->led_gpio, 1);
+
+	return 0;
+}
+
+static void skl_int3472_clk_unprepare(struct clk_hw *hw)
+{
+	struct int3472_gpio_clock *clk = to_int3472_clk(hw);
+
+	gpiod_set_value(clk->ena_gpio, 0);
+	if (clk->led_gpio)
+		gpiod_set_value(clk->led_gpio, 0);
+}
+
+static int skl_int3472_clk_enable(struct clk_hw *hw)
+{
+	/*
+	 * We're just turning a GPIO on to enable, which operation has the
+	 * potential to sleep. Given enable cannot sleep, but prepare can,
+	 * we toggle the GPIO in prepare instead. Thus, nothing to do here.
+	 */
+	return 0;
+}
+
+static void skl_int3472_clk_disable(struct clk_hw *hw)
+{
+	/* Likewise, nothing to do here... */
+}
+
+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 ?

+		dev_err(int3472->dev, "The buffer is too small\n");
+		goto out_free_buff;
+	}
+
+	ret = *(u32 *)(obj->buffer.pointer + CIO2_SENSOR_SSDB_MCLKSPEED_OFFSET);
+
+out_free_buff:
+	kfree(obj);
+	return ret;
+}
+
+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;

+}
+
+static const struct clk_ops skl_int3472_clock_ops = {
+	.prepare = skl_int3472_clk_prepare,
+	.unprepare = skl_int3472_clk_unprepare,
+	.enable = skl_int3472_clk_enable,
+	.disable = skl_int3472_clk_disable,
+	.recalc_rate = skl_int3472_clk_recalc_rate,
+};
+
+static struct int3472_sensor_config *
+skl_int3472_get_sensor_module_config(struct int3472_discrete_device *int3472)
+{
+	struct int3472_sensor_config *ret;
+	union acpi_object *obj;
+	unsigned int i;
+
+	obj = acpi_evaluate_dsm_typed(int3472->sensor->handle,
+				      &cio2_sensor_module_guid, 0x00,
+				      0x01, NULL, ACPI_TYPE_STRING);
+
+	if (!obj) {
+		dev_err(int3472->dev,
+			"Failed to get sensor module string from _DSM\n");
+		return ERR_PTR(-ENODEV);
+	}
+
+	if (obj->string.type != ACPI_TYPE_STRING) {
+		dev_err(int3472->dev,
+			"Sensor _DSM returned a non-string value\n");
+		ret = ERR_PTR(-EINVAL);
+		goto out_free_obj;
+	}
+
+	ret = NULL;
+	for (i = 0; i < ARRAY_SIZE(int3472_sensor_configs); i++) {
+		if (!strcmp(int3472_sensor_configs[i].sensor_module_name,
+			    obj->string.pointer)) {
+			ret = &int3472_sensor_configs[i];
+			break;
+		}
+	}
+
+out_free_obj:
+	ACPI_FREE(obj);
+	return ret;
+}
+
+static int skl_int3472_map_gpio_to_sensor(struct int3472_discrete_device *int3472,
+					  struct acpi_resource *ares,
+					  char *func, u32 polarity)
+{
+	char *path = ares->data.gpio.resource_source.string_ptr;
+	const struct int3472_sensor_config *sensor_config;
+	struct gpiod_lookup *table_entry;
+	struct acpi_device *adev;
+	acpi_handle handle;
+	acpi_status status;
+	int ret;
+
+	if (int3472->n_sensor_gpios >= INT3472_MAX_SENSOR_GPIOS) {
+		dev_warn(int3472->dev, "Too many GPIOs mapped\n");
+		return -EINVAL;
+	}
+
+	sensor_config = int3472->sensor_config;
+	if (!IS_ERR_OR_NULL(sensor_config) && sensor_config->function_maps) {
+		const struct int3472_gpio_function_remap *remap =
+			sensor_config->function_maps;
+
+		for (; remap->documented; ++remap)
+			if (!strcmp(func, remap->documented)) {
+				func = remap->actual;
+				break;
+			}

No strictly required, but I'd use curly braces for the for loop. Up to
you.

+	}
+
+	/* Functions mapped to NULL should not be mapped to the sensor */
+	if (!func)
+		return 0;
+
+	status = acpi_get_handle(NULL, path, &handle);
+	if (ACPI_FAILURE(status))
+		return -EINVAL;
+
+	ret = acpi_bus_get_device(handle, &adev);
+	if (ret)
+		return -ENODEV;
+
+	table_entry = &int3472->gpios.table[int3472->n_sensor_gpios];
+	table_entry->key = acpi_dev_name(adev);
+	table_entry->chip_hwnum = ares->data.gpio.pin_table[0];
+	table_entry->con_id = func;
+	table_entry->idx = 0;
+	table_entry->flags = polarity;
+
+	int3472->n_sensor_gpios++;
+
+	return 0;
+}
+
+static int skl_int3472_map_gpio_to_clk(struct int3472_discrete_device *int3472,
+				       struct acpi_resource *ares, u8 type)
+{
+	char *path = ares->data.gpio.resource_source.string_ptr;
+	struct gpio_desc *gpio;
+
+	switch (type) {
+	case INT3472_GPIO_TYPE_CLK_ENABLE:
+		gpio = acpi_get_gpiod(path, ares->data.gpio.pin_table[0],
+				      "int3472,clk-enable");
+		if (IS_ERR(gpio))
+			return (PTR_ERR(gpio));
+
+		int3472->clock.ena_gpio = gpio;
+		break;
+	case INT3472_GPIO_TYPE_PRIVACY_LED:
+		gpio = acpi_get_gpiod(path, ares->data.gpio.pin_table[0],
+				      "int3472,privacy-led");
+		if (IS_ERR(gpio))
+			return (PTR_ERR(gpio));
+
+		int3472->clock.led_gpio = gpio;
+		break;
+	default:
+		dev_err(int3472->dev, "Invalid GPIO type 0x%hx for clock\n",
+			type);

type being a u8, it should be %hhx, but I'd just use 0x%02x.

+		break;
+	}
+
+	return 0;
+}
+
+static int skl_int3472_register_clock(struct int3472_discrete_device *int3472)
+{
+	struct clk_init_data init = {
+		.ops = &skl_int3472_clock_ops,
+		.flags = CLK_GET_RATE_NOCACHE,
+	};
+	int ret = 0;
+
+	init.name = kasprintf(GFP_KERNEL, "%s-clk",
+			      acpi_dev_name(int3472->adev));
+	if (!init.name)
+		return -ENOMEM;
+
+	int3472->clock.frequency = skl_int3472_get_clk_frequency(int3472);
+
+	int3472->clock.clk_hw.init = &init;
+	int3472->clock.clk = clk_register(&int3472->adev->dev,
+					  &int3472->clock.clk_hw);
+	if (IS_ERR(int3472->clock.clk)) {
+		ret = PTR_ERR(int3472->clock.clk);
+		goto out_free_init_name;
+	}
+
+	int3472->clock.cl = clkdev_create(int3472->clock.clk, NULL,
+					  int3472->sensor_name);
+	if (!int3472->clock.cl) {
+		ret = -ENOMEM;
+		goto err_unregister_clk;
+	}
+
+	goto out_free_init_name;
+
+err_unregister_clk:
+	clk_unregister(int3472->clock.clk);
+out_free_init_name:
+	kfree(init.name);
+
+	return ret;
+}
+
+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)

+		return PTR_ERR(int3472->regulator.gpio);
+	}
+
+	cfg.dev = &int3472->adev->dev;
+	cfg.init_data = &init_data;
+	cfg.ena_gpiod = int3472->regulator.gpio;
+
+	int3472->regulator.rdev = regulator_register(&int3472->regulator.rdesc,
+						     &cfg);
+	if (IS_ERR(int3472->regulator.rdev)) {
+		ret = PTR_ERR(int3472->regulator.rdev);
+		goto err_free_gpio;
+	}
+
+	return 0;
+
+err_free_gpio:
+	gpiod_put(int3472->regulator.gpio);
+
+	return ret;
+}
+
+/**
+ * skl_int3472_handle_gpio_resources: Map PMIC resources to consuming sensor
+ * @ares: A pointer to a &struct acpi_resource
+ * @data: A pointer to a &struct int3472_discrete_device
+ *
+ * This function handles GPIO resources that are against an INT3472
+ * ACPI device, by checking the value of the corresponding _DSM entry.
+ * This will return a 32bit int, where the lowest byte represents the
+ * function of the GPIO pin:
+ *
+ * 0x00 Reset
+ * 0x01 Power down
+ * 0x0b Power enable
+ * 0x0c Clock enable
+ * 0x0d Privacy LED
+ *
+ * There are some known platform specific quirks where that does not quite
+ * hold up; for example where a pin with type 0x01 (Power down) is mapped to
+ * a sensor pin that performs a reset function or entries in _CRS and _DSM that
+ * do not actually correspond to a physical connection. These will be handled
+ * by the mapping sub-functions.
+ *
+ * GPIOs will either be mapped directly to the sensor device or else used
+ * to create clocks and regulators via the usual frameworks.
+ *
+ * Return:
+ * * 0		- When all resources found are handled properly.
+ * * -EINVAL	- If the resource is not a GPIO IO resource
+ * * -ENODEV	- If the resource has no corresponding _DSM entry
+ * * -Other	- Errors propagated from one of the sub-functions.
+ */
+static int skl_int3472_handle_gpio_resources(struct acpi_resource *ares,
+					     void *data)
+{
+	struct int3472_discrete_device *int3472 = data;
+	u16 pin = ares->data.gpio.pin_table[0];
+	union acpi_object *obj;
+	char *err_msg;
+	int ret = 0;
+	u8 type;
+
+	if (ares->type != ACPI_RESOURCE_TYPE_GPIO ||
+	    ares->data.gpio.connection_type != ACPI_RESOURCE_GPIO_TYPE_IO)
+		return 1; /* Deliberately positive so parsing continues */
+
+	/*
+	 * n_gpios + 2 because the index of this _DSM function is 1-based and
+	 * the first function is just a count.
+	 */
+	obj = acpi_evaluate_dsm_typed(int3472->adev->handle,
+				      &int3472_gpio_guid, 0x00,
+				      int3472->n_gpios + 2,
+				      NULL, ACPI_TYPE_INTEGER);
+
+	if (!obj) {
+		dev_warn(int3472->dev, "No _DSM entry for GPIO pin %u\n", pin);
+		return 1;
+	}
+
+	type = obj->integer.value & 0xff;
+
+	switch (type) {
+	case INT3472_GPIO_TYPE_RESET:
+		ret = skl_int3472_map_gpio_to_sensor(int3472, ares, "reset",
+						     GPIO_ACTIVE_LOW);
+		if (ret)
+			err_msg = "Failed to map reset pin to sensor\n";
+
+		break;
+	case INT3472_GPIO_TYPE_POWERDOWN:
+		ret = skl_int3472_map_gpio_to_sensor(int3472, ares,
+						     "powerdown",
+						     GPIO_ACTIVE_LOW);
+		if (ret)
+			err_msg = "Failed to map powerdown pin to sensor\n";
+
+		break;
+	case INT3472_GPIO_TYPE_CLK_ENABLE:
+	case INT3472_GPIO_TYPE_PRIVACY_LED:
+		ret = skl_int3472_map_gpio_to_clk(int3472, ares, type);
+		if (ret)
+			err_msg = "Failed to map GPIO to clock\n";
+
+		break;
+	case INT3472_GPIO_TYPE_POWER_ENABLE:
+		ret = skl_int3472_register_regulator(int3472, ares);
+		if (ret)
+			err_msg = "Failed to map regulator to sensor\n";
+
+		break;
+	default:
+		dev_warn(int3472->dev,
+			 "GPIO type 0x%02x unknown; the sensor may not work\n",
+			 type);
+		ret = 1;
+		break;
+	}
+
+	if (ret < 0 && ret != -EPROBE_DEFER)
+		dev_err(int3472->dev, err_msg);
+
+	int3472->n_gpios++;
+	ACPI_FREE(obj);
+
+	return ret;
+}
+
+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 ?

+
+	ret = acpi_dev_get_resources(int3472->adev, &resource_list,
+				     skl_int3472_handle_gpio_resources,
+				     int3472);
+	if (ret)
+		goto out_free_res_list;
+
+	if (int3472->clock.ena_gpio) {
+		ret = skl_int3472_register_clock(int3472);
+		if (ret)
+			goto out_free_res_list;
+	} else {
+		if (int3472->clock.led_gpio)
+			dev_warn(int3472->dev,
+				 "No clk GPIO. The privacy LED won't work\n");
+	}
+
+	int3472->gpios.dev_id = int3472->sensor_name;
+	gpiod_add_lookup_table(&int3472->gpios);
+
+out_free_res_list:
+	acpi_dev_free_resource_list(&resource_list);
+
+	return ret;
+}
+
+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.

+
+	int3472->sensor_name = kasprintf(GFP_KERNEL, I2C_DEV_NAME_FORMAT,
+					 acpi_dev_name(int3472->sensor));

This needs a NULL check.

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

+	{ .name = "tps68470-gpio" },
+	{ .name = "tps68470-clk" },
+	{ .name = "tps68470-regulator"},

Missing space before }.

+};
+
+static const struct regmap_config tps68470_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = TPS68470_REG_MAX,
+};
+
+static int tps68470_chip_init(struct device *dev, struct regmap *regmap)
+{
+	unsigned int version;
+	int ret;
+
+	/* Force software reset */
+	ret = regmap_write(regmap, TPS68470_REG_RESET, TPS68470_REG_RESET_MASK);
+	if (ret)
+		return ret;
+
+	ret = regmap_read(regmap, TPS68470_REG_REVID, &version);
+	if (ret) {
+		dev_err(dev, "Failed to read revision register: %d\n", ret);
+		return ret;
+	}
+
+	dev_info(dev, "TPS68470 REVID: 0x%02x\n", version);
+
+	return 0;
+}
+
+int skl_int3472_tps68470_probe(struct i2c_client *client)
+{
+	struct acpi_device *adev = ACPI_COMPANION(&client->dev);
+	struct int3472_cldb cldb = { 0 };
+	bool cldb_present = true;
+	struct regmap *regmap;
+	int ret;
+
+	regmap = devm_regmap_init_i2c(client, &tps68470_regmap_config);
+	if (IS_ERR(regmap)) {
+		dev_err(&client->dev, "Failed to create regmap: %ld\n",
+			PTR_ERR(regmap));
+		return PTR_ERR(regmap);
+	}
+
+	i2c_set_clientdata(client, regmap);
+
+	ret = tps68470_chip_init(&client->dev, regmap);
+	if (ret < 0) {
+		dev_err(&client->dev, "TPS68470 init error %d\n", ret);
+		return ret;
+	}
+
+	/*
+	 * Check CLDB buffer against the PMIC's adev. If present, then we check
+	 * the value of control_logic_type field and follow one of the
+	 * following scenarios:
+	 *
+	 *	1. No CLDB - likely ACPI tables designed for ChromeOS. We
+	 *	create platform devices for the GPIOs and OpRegion drivers.
+	 *
+	 *	2. CLDB, with control_logic_type = 2 - probably ACPI tables
+	 *	made for Windows 2-in-1 platforms. Register pdevs for GPIO,
+	 *	Clock and Regulator drivers to bind to.
+	 *
+	 *	3. Any other value in control_logic_type, we should never have
+	 *	gotten to this point; fail probe and return.
+	 */
+	ret = skl_int3472_fill_cldb(adev, &cldb);
+	if (!ret && cldb.control_logic_type != 2) {
+		dev_err(&client->dev, "Unsupported control logic type %u\n",
+			cldb.control_logic_type);
+		return -EINVAL;
+	}
+
+	if (ret)
+		cldb_present = false;
+
+	if (cldb_present)
+		ret = devm_mfd_add_devices(&client->dev, PLATFORM_DEVID_NONE,
+					   tps68470_w, ARRAY_SIZE(tps68470_w),
+					   NULL, 0, NULL);
+	else
+		ret = devm_mfd_add_devices(&client->dev, PLATFORM_DEVID_NONE,
+					   tps68470_c, ARRAY_SIZE(tps68470_c),
+					   NULL, 0, NULL);
+
+	if (ret) {
+		dev_err(&client->dev, "Failed to add MFD devices\n");
+		return ret;
+	}
+
+	return 0;
+}

-- 
Regards,

Laurent Pinchart