From 6e19e5d699f37e01f4e6c7b25f17cd603195d27c Mon Sep 17 00:00:00 2001 From: AngeloGioacchino Del Regno Date: Tue, 21 Jul 2026 11:36:19 +0200 Subject: [PATCH] spmi: Implement spmi_subdevice_alloc_and_add() and devm variant Some devices connected over the SPMI bus may be big, in the sense that those may be a complex of devices managed by a single chip over the SPMI bus, reachable through a single SID. Add new functions aimed at managing sub-devices of a SPMI device spmi_subdevice_alloc_and_add() and a spmi_subdevice_remove() for adding a new subdevice and removing it respectively, and also add their devm_* variants. The need for such functions comes from the existence of those complex Power Management ICs (PMICs), which feature one or many sub-devices, in some cases with these being even addressable on the chip in form of SPMI register ranges. Examples of those devices can be found in both Qualcomm platforms with their PMICs having PON, RTC, SDAM, GPIO controller, and other sub-devices, and in newer MediaTek platforms showing similar HW features and a similar layout with those also having many subdevs. Also, instead of generally exporting symbols, export them with a new "SPMI" namespace: all users will have to import this namespace to make use of the newly introduced exports. Reviewed-by: Jonathan Cameron Tested-by: Neil Armstrong # on SM8650-QRD Acked-by: Stephen Boyd Reviewed-by: Andy Shevchenko Signed-off-by: AngeloGioacchino Del Regno Signed-off-by: Stephen Boyd --- drivers/spmi/spmi-devres.c | 24 ++++++++++++ drivers/spmi/spmi.c | 78 ++++++++++++++++++++++++++++++++++++++ include/linux/spmi.h | 16 ++++++++ 3 files changed, 118 insertions(+) diff --git a/drivers/spmi/spmi-devres.c b/drivers/spmi/spmi-devres.c index 62c4b3f24d06..c3e889fe1b6e 100644 --- a/drivers/spmi/spmi-devres.c +++ b/drivers/spmi/spmi-devres.c @@ -60,5 +60,29 @@ int devm_spmi_controller_add(struct device *parent, struct spmi_controller *ctrl } EXPORT_SYMBOL_GPL(devm_spmi_controller_add); +static void devm_spmi_subdevice_remove(void *sub_sdev) +{ + spmi_subdevice_remove(sub_sdev); +} + +struct spmi_subdevice *devm_spmi_subdevice_alloc_and_add(struct device *dev, + struct spmi_device *sparent) +{ + struct spmi_subdevice *sub_sdev; + int ret; + + sub_sdev = spmi_subdevice_alloc_and_add(sparent); + if (IS_ERR(sub_sdev)) + return sub_sdev; + + ret = devm_add_action_or_reset(dev, devm_spmi_subdevice_remove, sub_sdev); + if (ret) + return ERR_PTR(ret); + + return sub_sdev; +} +EXPORT_SYMBOL_NS_GPL(devm_spmi_subdevice_alloc_and_add, "SPMI"); + MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("SPMI devres helpers"); +MODULE_IMPORT_NS("SPMI"); diff --git a/drivers/spmi/spmi.c b/drivers/spmi/spmi.c index ba4a980a35eb..bafb4c3e6c17 100644 --- a/drivers/spmi/spmi.c +++ b/drivers/spmi/spmi.c @@ -19,6 +19,7 @@ static bool is_registered; static DEFINE_IDA(ctrl_ida); +static DEFINE_IDA(spmi_subdevice_ida); static void spmi_dev_release(struct device *dev) { @@ -32,6 +33,19 @@ static const struct device_type spmi_dev_type = { .release = spmi_dev_release, }; +static void spmi_subdev_release(struct device *dev) +{ + struct spmi_device *sdev = to_spmi_device(dev); + struct spmi_subdevice *sub_sdev = container_of(sdev, struct spmi_subdevice, sdev); + + ida_free(&spmi_subdevice_ida, sub_sdev->devid); + kfree(sub_sdev); +} + +static const struct device_type spmi_subdev_type = { + .release = spmi_subdev_release, +}; + static void spmi_ctrl_release(struct device *dev) { struct spmi_controller *ctrl = to_spmi_controller(dev); @@ -88,6 +102,18 @@ void spmi_device_remove(struct spmi_device *sdev) } EXPORT_SYMBOL_GPL(spmi_device_remove); +/** + * spmi_subdevice_remove() - Remove an SPMI subdevice + * @sub_sdev: spmi_device to be removed + */ +void spmi_subdevice_remove(struct spmi_subdevice *sub_sdev) +{ + struct spmi_device *sdev = &sub_sdev->sdev; + + device_unregister(&sdev->dev); +} +EXPORT_SYMBOL_NS_GPL(spmi_subdevice_remove, "SPMI"); + static inline int spmi_cmd(struct spmi_controller *ctrl, u8 opcode, u8 sid) { @@ -429,6 +455,58 @@ struct spmi_device *spmi_device_alloc(struct spmi_controller *ctrl) } EXPORT_SYMBOL_GPL(spmi_device_alloc); +/** + * spmi_subdevice_alloc_and_add(): Allocate and add a new SPMI sub-device + * @sparent: SPMI parent device with previously registered SPMI controller + * + * Returns: + * Pointer to newly allocated SPMI sub-device for success or error pointer. + */ +struct spmi_subdevice *spmi_subdevice_alloc_and_add(struct spmi_device *sparent) +{ + struct spmi_subdevice *sub_sdev; + struct spmi_device *sdev; + int ret; + + sub_sdev = kzalloc_obj(*sub_sdev); + if (!sub_sdev) + return ERR_PTR(-ENOMEM); + + sdev = &sub_sdev->sdev; + sdev->ctrl = sparent->ctrl; + sdev->usid = sparent->usid; + + ret = ida_alloc(&spmi_subdevice_ida, GFP_KERNEL); + if (ret < 0) { + kfree(sub_sdev); + return ERR_PTR(ret); + } + sub_sdev->devid = ret; + + device_initialize(&sdev->dev); + sdev->dev.parent = &sparent->dev; + sdev->dev.bus = &spmi_bus_type; + sdev->dev.type = &spmi_subdev_type; + + ret = dev_set_name(&sdev->dev, "%u-%02x.%u.auto", + sdev->ctrl->nr, sdev->usid, sub_sdev->devid); + if (ret) + goto err_put_dev; + + ret = device_add(&sdev->dev); + if (ret) { + dev_err(&sdev->dev, "Can't add device, status %pe\n", ERR_PTR(ret)); + goto err_put_dev; + } + + return sub_sdev; + +err_put_dev: + put_device(&sdev->dev); + return ERR_PTR(ret); +} +EXPORT_SYMBOL_NS_GPL(spmi_subdevice_alloc_and_add, "SPMI"); + /** * spmi_controller_alloc() - Allocate a new SPMI controller * @parent: parent device diff --git a/include/linux/spmi.h b/include/linux/spmi.h index 4eb9564a7fb3..a78a8924b2ac 100644 --- a/include/linux/spmi.h +++ b/include/linux/spmi.h @@ -69,6 +69,22 @@ int spmi_device_add(struct spmi_device *sdev); void spmi_device_remove(struct spmi_device *sdev); +/** + * struct spmi_subdevice - Basic representation of an SPMI sub-device + * @sdev: Sub-device representation of an SPMI device + * @devid: Platform Device ID of an SPMI sub-device + */ +struct spmi_subdevice { + struct spmi_device sdev; + unsigned int devid; +}; + +struct spmi_subdevice *spmi_subdevice_alloc_and_add(struct spmi_device *sparent); +void spmi_subdevice_remove(struct spmi_subdevice *sdev); + +struct spmi_subdevice *devm_spmi_subdevice_alloc_and_add(struct device *dev, + struct spmi_device *sparent); + /** * struct spmi_controller - interface to the SPMI master controller * @dev: Driver model representation of the device.