| Message ID | 20241030072229.1013235-1-wenst@chromium.org |
|---|---|
| Headers | show |
| Series | platform/chrome: Introduce DT hardware prober | expand |
On 24-10-30 15:22, Chen-Yu Tsai wrote: > Add GPIO support to the simple helpers for the I2C OF component prober. > Components that the prober intends to probe likely require their > regulator supplies be enabled, and GPIOs be toggled to enable them or > bring them out of reset before they will respond to probe attempts. > Regulator supplies were handled in the previous patch. > > The assumption is that the same class of components to be probed are > always connected in the same fashion with the same regulator supply > and GPIO. The names may vary due to binding differences, but the > physical layout does not change. > > This supports at most one GPIO pin. The user must specify the GPIO name, > the polarity, and the amount of time to wait after the GPIO is toggled. > Devices with more than one GPIO pin likely require specific power > sequencing beyond what generic code can easily support. > > Signed-off-by: Chen-Yu Tsai <wenst@chromium.org> > Reviewed-by: Douglas Anderson <dianders@chromium.org> > Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > --- > diff --git a/include/linux/i2c-of-prober.h b/include/linux/i2c-of-prober.h > index df95aa6ad90e..a232f3cbb252 100644 > --- a/include/linux/i2c-of-prober.h > +++ b/include/linux/i2c-of-prober.h > @@ -85,6 +85,7 @@ int i2c_of_probe_component(struct device *dev, const struct i2c_of_probe_cfg *cf > * > * The following helpers are provided: > * * i2c_of_probe_simple_enable() > + * * i2c_of_probe_simple_cleanup_early() > * * i2c_of_probe_simple_cleanup() > */ > > @@ -92,14 +93,31 @@ int i2c_of_probe_component(struct device *dev, const struct i2c_of_probe_cfg *cf > * struct i2c_of_probe_simple_opts - Options for simple I2C component prober callbacks > * @res_node_compatible: Compatible string of device node to retrieve resources from. > * @supply_name: Name of regulator supply. > + * @gpio_name: Name of GPIO. NULL if no GPIO line is used. Empty string ("") if GPIO > + * line is unnamed. > * @post_power_on_delay_ms: Delay after regulators are powered on. Passed to msleep(). > + * @post_gpio_config_delay_ms: Delay after GPIO is configured. Passed to msleep(). > + * @gpio_assert_to_enable: %true if GPIO should be asserted, i.e. set to logical high, > + * to enable the component. > + * > + * This describes power sequences common for the class of components supported by the > + * simple component prober: > + * * @gpio_name is configured to the non-active setting according to @gpio_assert_to_enable. > + * * @supply_name regulator supply is enabled. > + * * Wait for @post_power_on_delay_ms to pass. > + * * @gpio_name is configured to the active setting according to @gpio_assert_to_enable. > + * * Wait for @post_gpio_config_delay_ms to pass. > */ > struct i2c_of_probe_simple_opts { > const char *res_node_compatible; > const char *supply_name; > + const char *gpio_name; > unsigned int post_power_on_delay_ms; > + unsigned int post_gpio_config_delay_ms; > + bool gpio_assert_to_enable; This header is missing '#include <linux/types.h>' for bool type. Otherwise compilation may fail with following error: ``` ./include/linux/i2c-of-prober.h:117:9: error: unknown type name ‘bool’ 117 | bool gpio_assert_to_enable; | ^~~~ ./include/linux/i2c-of-prober.h:12:1: note: ‘bool’ is defined in header ‘<stdbool.h>’; this is probably fixable by adding ‘#include <stdbool.h>’ 11 | #include <linux/kconfig.h> +++ |+#include <stdbool.h> 12 | ``` > }; > > +struct gpio_desc; > struct regulator; > > struct i2c_of_probe_simple_ctx { > @@ -107,9 +125,11 @@ struct i2c_of_probe_simple_ctx { > const struct i2c_of_probe_simple_opts *opts; > /* private: internal fields for helpers. */ > struct regulator *supply; > + struct gpio_desc *gpiod; > }; > > int i2c_of_probe_simple_enable(struct device *dev, struct device_node *bus_node, void *data); > +void i2c_of_probe_simple_cleanup_early(struct device *dev, void *data); > void i2c_of_probe_simple_cleanup(struct device *dev, void *data); > > extern struct i2c_of_probe_ops i2c_of_probe_simple_ops; > -- > 2.47.0.163.g1226f6d8fa-goog >
On Wed, Nov 6, 2024 at 12:14 AM Andrey Skvortsov <andrej.skvortzov@gmail.com> wrote: > > On 24-10-30 15:22, Chen-Yu Tsai wrote: > > Add GPIO support to the simple helpers for the I2C OF component prober. > > Components that the prober intends to probe likely require their > > regulator supplies be enabled, and GPIOs be toggled to enable them or > > bring them out of reset before they will respond to probe attempts. > > Regulator supplies were handled in the previous patch. > > > > The assumption is that the same class of components to be probed are > > always connected in the same fashion with the same regulator supply > > and GPIO. The names may vary due to binding differences, but the > > physical layout does not change. > > > > This supports at most one GPIO pin. The user must specify the GPIO name, > > the polarity, and the amount of time to wait after the GPIO is toggled. > > Devices with more than one GPIO pin likely require specific power > > sequencing beyond what generic code can easily support. > > > > Signed-off-by: Chen-Yu Tsai <wenst@chromium.org> > > Reviewed-by: Douglas Anderson <dianders@chromium.org> > > Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > > --- > > > diff --git a/include/linux/i2c-of-prober.h b/include/linux/i2c-of-prober.h > > index df95aa6ad90e..a232f3cbb252 100644 > > --- a/include/linux/i2c-of-prober.h > > +++ b/include/linux/i2c-of-prober.h > > @@ -85,6 +85,7 @@ int i2c_of_probe_component(struct device *dev, const struct i2c_of_probe_cfg *cf > > * > > * The following helpers are provided: > > * * i2c_of_probe_simple_enable() > > + * * i2c_of_probe_simple_cleanup_early() > > * * i2c_of_probe_simple_cleanup() > > */ > > > > @@ -92,14 +93,31 @@ int i2c_of_probe_component(struct device *dev, const struct i2c_of_probe_cfg *cf > > * struct i2c_of_probe_simple_opts - Options for simple I2C component prober callbacks > > * @res_node_compatible: Compatible string of device node to retrieve resources from. > > * @supply_name: Name of regulator supply. > > + * @gpio_name: Name of GPIO. NULL if no GPIO line is used. Empty string ("") if GPIO > > + * line is unnamed. > > * @post_power_on_delay_ms: Delay after regulators are powered on. Passed to msleep(). > > + * @post_gpio_config_delay_ms: Delay after GPIO is configured. Passed to msleep(). > > + * @gpio_assert_to_enable: %true if GPIO should be asserted, i.e. set to logical high, > > + * to enable the component. > > + * > > + * This describes power sequences common for the class of components supported by the > > + * simple component prober: > > + * * @gpio_name is configured to the non-active setting according to @gpio_assert_to_enable. > > + * * @supply_name regulator supply is enabled. > > + * * Wait for @post_power_on_delay_ms to pass. > > + * * @gpio_name is configured to the active setting according to @gpio_assert_to_enable. > > + * * Wait for @post_gpio_config_delay_ms to pass. > > */ > > struct i2c_of_probe_simple_opts { > > const char *res_node_compatible; > > const char *supply_name; > > + const char *gpio_name; > > unsigned int post_power_on_delay_ms; > > + unsigned int post_gpio_config_delay_ms; > > + bool gpio_assert_to_enable; > > This header is missing '#include <linux/types.h>' for bool > type. Otherwise compilation may fail with following error: > > ``` > ./include/linux/i2c-of-prober.h:117:9: error: unknown type name ‘bool’ > 117 | bool gpio_assert_to_enable; > | ^~~~ > ./include/linux/i2c-of-prober.h:12:1: note: ‘bool’ is defined in header ‘<stdbool.h>’; this is probably fixable by adding ‘#include <stdbool.h>’ > 11 | #include <linux/kconfig.h> > +++ |+#include <stdbool.h> > 12 | > ``` Thanks for catching this. I'll send an update. > > }; > > > > +struct gpio_desc; > > struct regulator; > > > > struct i2c_of_probe_simple_ctx { > > @@ -107,9 +125,11 @@ struct i2c_of_probe_simple_ctx { > > const struct i2c_of_probe_simple_opts *opts; > > /* private: internal fields for helpers. */ > > struct regulator *supply; > > + struct gpio_desc *gpiod; > > }; > > > > int i2c_of_probe_simple_enable(struct device *dev, struct device_node *bus_node, void *data); > > +void i2c_of_probe_simple_cleanup_early(struct device *dev, void *data); > > void i2c_of_probe_simple_cleanup(struct device *dev, void *data); > > > > extern struct i2c_of_probe_ops i2c_of_probe_simple_ops; > > -- > > 2.47.0.163.g1226f6d8fa-goog > > > > -- > Best regards, > Andrey Skvortsov
Hi everyone, This is v10 of my "of: Introduce hardware prober driver" series. v10 includes some minor changes pointed out by Andy and Doug. Everything is fully reviewed and ready to be merged. The older changelog entries have been moved to the bottom of the cover letter. Changes since v9: - Picked up review-bys - Added inclusion of stddef.h for NULL - Added "noautosel" stable tag to the device tree patch For the I2C component (touchscreens and trackpads) case from the original series, the hardware prober driver finds the particular class of device in the device tree, gets its parent I2C adapter, and tries to initiate a simple I2C read for each device under that I2C bus. When it finds one that responds, it considers that one present, marks it as "okay", and returns, letting the driver core actually probe the device. This works fine in most cases since these components are connected via a ribbon cable and always have the same resources. The prober will also grab these resources and enable them. The other case, selecting a display panel to use based on the SKU ID from the firmware, hit a bit of an issue with fixing the OF graph. It has been left out since v3. Patch 1 adds of_changeset_update_prop_string(), as requested by Rob. Patch 2 adds for_each_child_of_node_with_prefix(), as suggested by Andy. Patch 3 implements probing the I2C bus for presence of components as a hookable helper function in the I2C core. Patch 4 implements regulator supply support as a set of simple helpers for the I2C component prober. Patch 5 implements GPIO support for the I2C component prober simple helpers. Patch 6 adds a ChromeOS specific DT hardware prober. This initial version targets the Hana Chromebooks, probing its I2C trackpads and touchscreens. Patch 7 modifies the Hana device tree and marks the touchscreens and trackpads as "fail-needs-probe", ready for the driver to probe. The regulator parts were merged separately with an immutable tag [1]. Rob already gave his Reviewed-by for the OF bits, and I assume he is OK with them going through a different branch. So I believe it is fine for Wolfram to take all the patch except the last one through the I2C tree. The last DTS patch can be merged through the MediaTek tree once the driver bits land. Thanks ChenYu [1] https://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator.git/tag/?h=regulator-of-get-optional Changes since v8: - Link to v8: https://lore.kernel.org/all/20241008073430.3992087-1-wenst@chromium.org/ - Patch "i2c: core: Remove extra space in Makefile" was merged and dropped from this version - Patch 3 "i2c: Introduce OF component probe function" - Added missing include of <linux/kconfig.h> to i2c-of-prober.h - Expanded description of i2c_of_probe_ops::enable to mention that returning -EPROBE_DEFER is valid (Doug) - Reworded descrption of i2c_of_probe_ops::cleanup_early to avoid confusion with i2c_of_probe_ops::enable (Doug) - Reworked i2c_of_probe_get_i2c_node() to return NULL on failure, matching most functions that return |struct device_node *|. - Patch 4 "i2c: of-prober: Add simple helpers for regulator support" - Picked up Doug's reviewed-by - Patch 5 "i2c: of-prober: Add GPIO support to simple helpers" - Moved |struct gpio_desc| forward declaration before |struct regulator| (Andy) - Dropped GPIO descriptor validity check from i2c_of_probe_simple_disable_gpio(); GPIO functions check it (Andy) - Dropped comment from i2c_of_probe_simple_disable_gpio() (Doug) - Reworded comment in i2c_of_probe_simple_cleanup() (Doug) - Picked up Doug's reviewed-by - Patch 6 "platform/chrome: Introduce device tree hardware prober" - Added trailing commas on last field in struct variable declarations (Andy) - Added macros wrapping chromeos_i2c_probe_dumb_* and chromeos_i2c_probe_simple_*_cfg variable declarations (Andy) - Split up hw_prober_platforms into one field per line (Andy) - Picked up Doug's reviewed-by - Patch 7 "arm64: dts: mediatek: mt8173-elm-hana: Mark touchscreens and trackpads as fail" Changes since v7: - Link to v7: https://lore.kernel.org/all/20240911072751.365361-1-wenst@chromium.org/ - Patch 2 "of: base: Add for_each_child_of_node_with_prefix()" - Collected Rob's Reviewed-by - Patch 3 "i2c: core: Remove extra space in Makefile" - Collected Andi's Reviewed-by - Patch 4 "i2c: Introduce OF component probe function" - Dropped log level of "enabling component" to debug - Dropped file name from header file - Reverted to __free() cleanup for i2c bus node - Corrected "failed-needs-probe" to "fail-needs-probe" in commit message - Fixed incorrectly positioned period ('.') in commit message - Expanded description of i2c_of_probe_component() - Expanded comment explaining check for "available" devices to note that if such a device is found then the i2c probe function becomes a no-op - Simplified check for "available" devices for-each loop - Expanded description of @free_resources_early callback to explicitly state that it is not called if no working components are found - Dropped !cfg check - Replaced "fail" with "fail-needs-probe" in i2c_of_probe_component() kernel doc - Combined callbacks (.get_resources with .enable; .cleanup with .free_resources_late); .free_resources_early renamed to .cleanup_early - Patch 5 "i2c: of-prober: Add simple helpers for regulator support" - Reworded comment in i2c_of_probe_simple_get_supply() as suggested (Andy) - Dropped mention of time unit in struct i2c_of_probe_simple_opts kernel doc (Andy) - Added mention of common GPIO line usages ("enable" or "reset") in I2C OF component prober kernel doc (Doug) - Added check for non-zero delay before msleep() (Doug) - Combined callback helpers (.get_resources with .enable; .cleanup with .free_resources_late) - Patch 6 "i2c: of-prober: Add GPIO support to simple helpers" - Dropped mention of time unit in struct i2c_of_probe_simple_opts kernel doc (Andy) - Added check for non-zero delay before msleep() (Doug) - Simplified GPIO name check and reverse conditional branches (Andy) - Added description about the supported power sequence - Switched GPIO usage to logical levels (Doug) - Changed some variable names and comments to fit - Added description of power sequence to struct i2c_of_probe_simple_opts (Doug) - Added comment saying i2c_of_probe_simple_put_gpiod() might be no-op (Doug) - Combined callbacks (.get_resources with .enable; .cleanup with .free_resources_late); renamed i2c_of_probe_simple_free_res_early() to i2c_of_probe_simple_cleanup_early() - Patch 7 "platform/chrome: Introduce device tree hardware prober" - Corrected Makefile item order - Replaced "failed-needs-probe" with "fail-needs-probe" in commit message - Added include of "linux/of.h" for of_machine_is_compatible() - Switched to simple probe helpers for trackpads on Hana - Patch 8 "arm64: dts: mediatek: mt8173-elm-hana: Mark touchscreens and trackpads as fail" - Mark touchscreen@40 as "fail-needs-probe" as well Changes since v6: - Link to v6: https://lore.kernel.org/all/20240904090016.2841572-1-wenst@chromium.org/ - Dropped patch "gpiolib: Add gpio_property_name_length()" No longer needed - Dropped patch "regulator: Move OF-specific regulator lookup code to of_regulator.c" Already merged - Patch 2 "of: base: Add for_each_child_of_node_with_prefix()" - Changed helper name to "for_each_child_of_node_with_prefix()" - Patch 4 "regulator: Add of_regulator_get_optional() for pure DT regulator lookup" - Was "regulator: Do pure DT regulator lookup in of_regulator_bulk_get_all()" - Changed reference [1] to Link: tag - Rebased on top of commit 401d078eaf2e ("regulator: of: Refactor of_get_*regulator() to decrease indentation") - Exported of_regulator_get_optional() - Changed commit message to focus on "of_regulator_get_optional()" - Dropped change to of_regulator_bulk_get_all() - Patch 5 "i2c: core: Remove extra space in Makefile" - Collected Andy's Reviewed-by - Patch 6 "i2c: Introduce OF component probe function" - Correctly replaced for_each_child_of_node_scoped() with for_each_child_of_node_with_prefix() - Added namespace for exported symbols - Made the probe function a framework with hooks - Split out a new header file - Added MAINTAINERS entry - Reworded kernel-doc - Dropped usage of __free from i2c_of_probe_component() since error path cleanup is needed anyway - Patch 7 "i2c: of-prober: Add simple helpers for regulator support" - Moved change of of_get_next_child_scoped() to of_get_next_child_with_prefix() to previous patch - Restructured into helpers for the I2C OF component prober - Reduced to only handle one regulator - Commit message updated - Patch 8 "i2c: of-prober: Add GPIO support to simple helpers" - Restructured into helpers for the I2C OF component prober - Reduced to only handle one GPIO - Set GPIO to input on (failure) cleanup - Updated commit message - Patch 9 "platform/chrome: Introduce device tree hardware prober" - Adapted to new I2C OF prober interface - Collected Acked-by tag Changes since v5: - Link to v5: https://lore.kernel.org/all/20240822092006.3134096-1-wenst@chromium.org/ - Patch 1 "of: dynamic: Add of_changeset_update_prop_string" - Collected Rob's reviewed-by - Patch 2 "of: base: Add for_each_child_of_node_with_prefix_scoped()" - New patch - Patch 3 "regulator: Move OF-specific regulator lookup code to of_regulator.c" - Fix kerneldoc format of of_regulator_dev_lookup() - Fix stub compile error for !CONFIG_OF in drivers/regulator/internal.h - Patch 4 "regulator: Split up _regulator_get()" - Fixed kerneldoc "Return" section format for _regulator_get_common() - Slightly reworded return value description - Patch 5 "regulator: Do pure DT regulator lookup in of_regulator_bulk_get_all()" - Used "dev_of_node(dev)" instead of "dev->of_node" - Replaced "dev_printk" with "dev_printk()" in kerneldoc mentions - Fixed kerneldoc "Return" section format for of_regulator_get_optional() - Fix @np parameter name in of_regulator_dev_lookup() kerneldoc - Patch 6 "gpiolib: Add gpio_property_name_length()" - Changed function name to "gpio_get_property_name_length()" - Changed argument name to "propname" - Clarified return value for "*-<GPIO suffix>" case - Reworked according to Andy's suggestion - Added stub function - Patch 7 "i2c: core: Remove extra space in Makefile" - New patch - Patch 8 "i2c: Introduce OF component probe function" - Fixed indent in Makefile - Split regulator and GPIO TODO items - Reversed final conditional in i2c_of_probe_enable_node() - Patch 9 "i2c: of-prober: Add regulator support" - Split of_regulator_bulk_get_all() return value check and explain "ret == 0" case - Switched to of_get_next_child_with_prefix_scoped() where applicable - Used krealloc_array() instead of directly calculating size - copy whole regulator array in one memcpy() call - Drop "0" from struct zeroing initializer - Split out regulator helper from i2c_of_probe_enable_res() to keep code cleaner when combined with the next patch - Added options for customizing power sequencing delay - Rename i2c_of_probe_get_regulator() to i2c_of_probe_get_regulators() - Add i2c_of_probe_free_regulator() helper - Patch 10 "i2c: of-prober: Add GPIO support" - Renamed "con" to "propname" in i2c_of_probe_get_gpiod() - Copy string first and check return value of strscpy() for overflow in i2c_of_probe_get_gpiod() - Add parenthesis around "enable" and "reset" GPIO names in comments - Split resource count debug message into two separate lines - Split out GPIO helper from i2c_of_probe_enable_res() to keep code cleaner following the previous patch - Adopted options for customizing power sequencing delay following previous patch - Patch 11 "platform/chrome: Introduce device tree hardware prober" - Adapt to new i2c_of_probe_component() parameters - Patch 12 "arm64: dts: mediatek: mt8173-elm-hana: Mark touchscreens and trackpads as fail" - None See v5 cover letter for previous change logs. Chen-Yu Tsai (7): of: dynamic: Add of_changeset_update_prop_string of: base: Add for_each_child_of_node_with_prefix() i2c: Introduce OF component probe function i2c: of-prober: Add simple helpers for regulator support i2c: of-prober: Add GPIO support to simple helpers platform/chrome: Introduce device tree hardware prober arm64: dts: mediatek: mt8173-elm-hana: Mark touchscreens and trackpads as fail MAINTAINERS | 8 + .../boot/dts/mediatek/mt8173-elm-hana.dtsi | 14 + arch/arm64/boot/dts/mediatek/mt8173-elm.dtsi | 4 +- drivers/i2c/Makefile | 1 + drivers/i2c/i2c-core-of-prober.c | 415 ++++++++++++++++++ drivers/of/base.c | 35 ++ drivers/of/dynamic.c | 44 ++ drivers/platform/chrome/Kconfig | 11 + drivers/platform/chrome/Makefile | 1 + .../platform/chrome/chromeos_of_hw_prober.c | 154 +++++++ include/linux/i2c-of-prober.h | 139 ++++++ include/linux/of.h | 13 + 12 files changed, 837 insertions(+), 2 deletions(-) create mode 100644 drivers/i2c/i2c-core-of-prober.c create mode 100644 drivers/platform/chrome/chromeos_of_hw_prober.c create mode 100644 include/linux/i2c-of-prober.h