Hello Hans and Bingbu (and thanks for both versions of the patch)
On 31/05/2023 14:44, Hans de Goede wrote:
From: Bingbu Cao <bingbu.cao@xxxxxxxxx>
On some platforms, the imaging clock should be controlled by evaluating
specific clock device's _DSM method instead of setting gpio, so this
change register clock if no gpio based clock and then use the _DSM method
to enable and disable clock.
Interesting - is that a common thing? Are there other camera-related resources that are controlled
in a similar way? I still don't know how to drive the infrared LED on most Surface platforms, so now
I'm wondering if they need something similar doing.
It does seem a bit strange for this to be a _DSM method against the INT3472 rather than part of _PS0
against the camera itself - isn't that where you'd usually find such things?
Signed-off-by: Bingbu Cao <bingbu.cao@xxxxxxxxx>
Signed-off-by: Hao Yao <hao.yao@xxxxxxxxx>
Link: https://lore.kernel.org/r/20230524035135.90315-2-bingbu.cao@xxxxxxxxx
---
Changes in v2 (Hans de Goede):
- Minor comment / code changes (address Andy's review remarks)
- Add a acpi_check_dsm() call
- Return 0 instead of error if we already have a GPIO clk or if
acpi_check_dsm() fails
- Rename skl_int3472_register_clock() -> skl_int3472_register_gpio_clock()
and name the new function: skl_int3472_register_dsm_clock()
- Move the skl_int3472_register_dsm_clock() call to after
acpi_dev_free_resource_list() and add error checking for it
I think all these changes are good ones.
---
.../x86/intel/int3472/clk_and_regulator.c | 89 ++++++++++++++++++-
drivers/platform/x86/intel/int3472/common.h | 10 ++-
drivers/platform/x86/intel/int3472/discrete.c | 8 +-
3 files changed, 99 insertions(+), 8 deletions(-)
diff --git a/drivers/platform/x86/intel/int3472/clk_and_regulator.c b/drivers/platform/x86/intel/int3472/clk_and_regulator.c
index 1086c3d83494..9bcf8c64b8e7 100644
--- a/drivers/platform/x86/intel/int3472/clk_and_regulator.c
+++ b/drivers/platform/x86/intel/int3472/clk_and_regulator.c
@@ -11,6 +11,37 @@
#include "common.h"
+/*
+ * 82c0d13a-78c5-4244-9bb1-eb8b539a8d11
+ * This _DSM GUID allows controlling the sensor clk when it is not controlled
+ * through a GPIO.
+ */
+static const guid_t img_clk_guid =
+ GUID_INIT(0x82c0d13a, 0x78c5, 0x4244,
+ 0x9b, 0xb1, 0xeb, 0x8b, 0x53, 0x9a, 0x8d, 0x11);
+
+static void skl_int3472_enable_clk_acpi_method(struct int3472_gpio_clock *clk,
+ bool enable)
+{
+ struct int3472_discrete_device *int3472 = to_int3472_device(clk);
+ union acpi_object args[3];
+ union acpi_object argv4;
+
+ args[0].integer.type = ACPI_TYPE_INTEGER;
+ args[0].integer.value = clk->imgclk_index;
+ args[1].integer.type = ACPI_TYPE_INTEGER;
+ args[1].integer.value = enable ? 1 : 0;
+ args[2].integer.type = ACPI_TYPE_INTEGER;
+ args[2].integer.value = 1;
+
+ argv4.type = ACPI_TYPE_PACKAGE;
+ argv4.package.count = 3;
+ argv4.package.elements = args;
+
+ acpi_evaluate_dsm(acpi_device_handle(int3472->adev), &img_clk_guid,
+ 0, 1, &argv4);
+}
I'm not really sure what error modes something like this might have, but acpi_evaluate_dsm() at
least can fail - is there no value in error checking here so that it could be returned by
skl_int3472_clk_prepare() below?
+
/*
* 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
@@ -22,7 +53,11 @@ static int skl_int3472_clk_prepare(struct clk_hw *hw)
{
struct int3472_gpio_clock *clk = to_int3472_clk(hw);
- gpiod_set_value_cansleep(clk->ena_gpio, 1);
+ if (clk->ena_gpio)
+ gpiod_set_value_cansleep(clk->ena_gpio, 1);
+ else
+ skl_int3472_enable_clk_acpi_method(clk, 1);
+
return 0;
}
@@ -30,7 +65,10 @@ static void skl_int3472_clk_unprepare(struct clk_hw *hw)
{
struct int3472_gpio_clock *clk = to_int3472_clk(hw);
- gpiod_set_value_cansleep(clk->ena_gpio, 0);
+ if (clk->ena_gpio)
+ gpiod_set_value_cansleep(clk->ena_gpio, 0);
+ else
+ skl_int3472_enable_clk_acpi_method(clk, 0);
}
static int skl_int3472_clk_enable(struct clk_hw *hw)
@@ -86,8 +124,51 @@ static const struct clk_ops skl_int3472_clock_ops = {
.recalc_rate = skl_int3472_clk_recalc_rate,
};
-int skl_int3472_register_clock(struct int3472_discrete_device *int3472,
- struct acpi_resource_gpio *agpio, u32 polarity)
+int skl_int3472_register_dsm_clock(struct int3472_discrete_device *int3472)
+{
+ struct acpi_device *adev = int3472->adev;
+ struct clk_init_data init = {
+ .ops = &skl_int3472_clock_ops,
+ .flags = CLK_GET_RATE_NOCACHE,
+ };
+ int ret;
+
+ if (int3472->clock.cl)
+ return 0; /* A GPIO controlled clk has already been registered */
+
+ if (!acpi_check_dsm(adev->handle, &img_clk_guid, 0, BIT(1)))
+ return 0; /* DSM clock control is not available */
+
+ init.name = kasprintf(GFP_KERNEL, "%s-clk", acpi_dev_name(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(&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;
+ }
+
+ kfree(init.name);
+ return 0;
+
+err_unregister_clk:
+ clk_unregister(int3472->clock.clk);
+out_free_init_name:
+ kfree(init.name);
+ return ret;
+}
+
+int skl_int3472_register_gpio_clock(struct int3472_discrete_device *int3472,
+ struct acpi_resource_gpio *agpio, u32 polarity)
{
char *path = agpio->resource_source.string_ptr;
struct clk_init_data init = {
diff --git a/drivers/platform/x86/intel/int3472/common.h b/drivers/platform/x86/intel/int3472/common.h
index 61688e450ce5..10a72f42a998 100644
--- a/drivers/platform/x86/intel/int3472/common.h
+++ b/drivers/platform/x86/intel/int3472/common.h
@@ -64,7 +64,9 @@ struct int3472_cldb {
u8 control_logic_type;
u8 control_logic_id;
u8 sensor_card_sku;
- u8 reserved[28];
+ u8 reserved[10];
+ u8 clock_source;
+ u8 reserved2[17];
Not really a comment on the functionality of the patch, but can we not just get the rest of those
fields filled out?
};
struct int3472_gpio_function_remap {
@@ -100,6 +102,7 @@ struct int3472_discrete_device {
struct clk_lookup *cl;
struct gpio_desc *ena_gpio;
u32 frequency;
+ u8 imgclk_index;
} clock;
This struct is called "int3472_gpio_clock" but perhaps now ought to just be "int3472_clock"
struct int3472_pled {
@@ -121,8 +124,9 @@ int skl_int3472_get_sensor_adev_and_name(struct device *dev,
struct acpi_device **sensor_adev_ret,
const char **name_ret);
-int skl_int3472_register_clock(struct int3472_discrete_device *int3472,
- struct acpi_resource_gpio *agpio, u32 polarity);
+int skl_int3472_register_gpio_clock(struct int3472_discrete_device *int3472,
+ struct acpi_resource_gpio *agpio, u32 polarity);
+int skl_int3472_register_dsm_clock(struct int3472_discrete_device *int3472);
void skl_int3472_unregister_clock(struct int3472_discrete_device *int3472);
int skl_int3472_register_regulator(struct int3472_discrete_device *int3472,
diff --git a/drivers/platform/x86/intel/int3472/discrete.c b/drivers/platform/x86/intel/int3472/discrete.c
index ef020e23e596..8111579a59d4 100644
--- a/drivers/platform/x86/intel/int3472/discrete.c
+++ b/drivers/platform/x86/intel/int3472/discrete.c
@@ -258,7 +258,7 @@ static int skl_int3472_handle_gpio_resources(struct acpi_resource *ares,
break;
case INT3472_GPIO_TYPE_CLK_ENABLE:
- ret = skl_int3472_register_clock(int3472, agpio, polarity);
+ ret = skl_int3472_register_gpio_clock(int3472, agpio, polarity);
if (ret)
err_msg = "Failed to register clock\n";
@@ -311,6 +311,11 @@ static int skl_int3472_parse_crs(struct int3472_discrete_device *int3472)
acpi_dev_free_resource_list(&resource_list);
+ /* Register _DSM based clock (no-op if a GPIO clock was already registered) */
+ ret = skl_int3472_register_dsm_clock(int3472);
+ if (ret < 0)
+ return ret;
+
int3472->gpios.dev_id = int3472->sensor_name;
gpiod_add_lookup_table(&int3472->gpios);
@@ -356,6 +361,7 @@ static int skl_int3472_discrete_probe(struct platform_device *pdev)
int3472->adev = adev;
int3472->dev = &pdev->dev;
platform_set_drvdata(pdev, int3472);
+ int3472->clock.imgclk_index = cldb.clock_source;
ret = skl_int3472_get_sensor_adev_and_name(&pdev->dev, &int3472->sensor,
&int3472->sensor_name);
