* [PATCH v3 0/2] Add support for SA8255P in the phy-qcom-snps-femto-v2 phy driver
@ 2026-10-02 9:41 ` Mattijs Korpershoek
0 siblings, 0 replies; 10+ messages in thread
From: Mattijs Korpershoek @ 2026-10-02 9:41 UTC (permalink / raw)
To: Vinod Koul, Neil Armstrong, Rob Herring, Krzysztof Kozlowski,
Conor Dooley, Philipp Zabel
Cc: linux-arm-msm, linux-phy, devicetree, linux-kernel,
Mattijs Korpershoek, Krzysztof Kozlowski, Sriram Dash
The Qualcomm automotive SA8255p SoC relies on firmware to configure
platform resources, including clocks, interconnects and TLMM.
The driver requests resources operations over SCMI using power protocols.
The SCMI power protocol enables or disables resources like clocks,
interconnect paths, and TLMM (GPIOs) using runtime PM framework APIs,
such as resume/suspend, to control power on/off.
Power domain "core" controls the GDSC, resets, and TLMM (GPIOs)
whereas power domain "transfer" controls clocks and interconnects.
Patch 1 adds the binding for sa8255p. Similarly to what has been done
for I2C [1], this is a separate binding.
Patch 2 adds the driver change, which is based on a public vendor
patch from qualcomm [2].
I did the following changes on top of that:
* Use devm_add_action_or_reset() for dev_pm_domain_detach_list() instead
of implementing a driver .remove()
* Changed power domain names to drop 'usb_' prefix
* Fixed various error handling paths
* Added suspend/resume support
This has been tested on next-20260728 with a Ride4 SA8775P board that
has SCMI firmware (which is compatible).
[1] https://lore.kernel.org/all/20260617-enable-i2c-on-sa8255p-v7-1-ad736dbeab57@oss.qualcomm.com/
[2] https://git.codelinaro.org/clo/le/meta-qti-auto-kernel/-/blob/LY.AU.0.1.0.r1-16800-gen4meta.0/recipes-kernel/linux/files/usb/0014-PENDING-phy-qcom-snps-femto-v2-Add-support-for-SA825.patch
Signed-off-by: Mattijs Korpershoek <mkorpershoek@kernel.org>
---
Changes in v3:
- Applied R-b from Krzysztof and Neil
- Link to v2: https://patch.msgid.link/20260831-phy-qcom-snps-femto-v2-8255-v2-0-dc6197ffde1b@kernel.org
Changes in v2:
- Move 'core' as first domain, before 'transfer' (Krzysztof)
- Reworded binding commit message to be more precise about the various
domains ('core', 'transfer' and 'perf') (Krzysztof)
- Link to v1: https://patch.msgid.link/20260730-phy-qcom-snps-femto-v2-8255-v1-0-8b8bf5105a68@kernel.org
---
Mattijs Korpershoek (1):
dt-bindings: phy: Add sa8255p high-speed USB PHY
Sriram Dash (1):
phy: qcom-snps-femto-v2: Add support for SA8255P
.../bindings/phy/qcom,sa8255p-usb-hs-phy.yaml | 52 +++++++++
drivers/phy/qualcomm/phy-qcom-snps-femto-v2.c | 127 +++++++++++++++++++--
2 files changed, 170 insertions(+), 9 deletions(-)
---
base-commit: e30626823a406725ce29bc75cb8ec467d3e1e326
change-id: 20260729-phy-qcom-snps-femto-v2-8255-90ffe7674001
Best regards,
--
Mattijs Korpershoek <mkorpershoek@kernel.org>
^ permalink raw reply [flat|nested] 10+ messages in thread* [PATCH v3 0/2] Add support for SA8255P in the phy-qcom-snps-femto-v2 phy driver @ 2026-10-02 9:41 ` Mattijs Korpershoek 0 siblings, 0 replies; 10+ messages in thread From: Mattijs Korpershoek @ 2026-10-02 9:41 UTC (permalink / raw) To: Vinod Koul, Neil Armstrong, Rob Herring, Krzysztof Kozlowski, Conor Dooley, Philipp Zabel Cc: linux-arm-msm, linux-phy, devicetree, linux-kernel, Mattijs Korpershoek, Krzysztof Kozlowski, Sriram Dash The Qualcomm automotive SA8255p SoC relies on firmware to configure platform resources, including clocks, interconnects and TLMM. The driver requests resources operations over SCMI using power protocols. The SCMI power protocol enables or disables resources like clocks, interconnect paths, and TLMM (GPIOs) using runtime PM framework APIs, such as resume/suspend, to control power on/off. Power domain "core" controls the GDSC, resets, and TLMM (GPIOs) whereas power domain "transfer" controls clocks and interconnects. Patch 1 adds the binding for sa8255p. Similarly to what has been done for I2C [1], this is a separate binding. Patch 2 adds the driver change, which is based on a public vendor patch from qualcomm [2]. I did the following changes on top of that: * Use devm_add_action_or_reset() for dev_pm_domain_detach_list() instead of implementing a driver .remove() * Changed power domain names to drop 'usb_' prefix * Fixed various error handling paths * Added suspend/resume support This has been tested on next-20260728 with a Ride4 SA8775P board that has SCMI firmware (which is compatible). [1] https://lore.kernel.org/all/20260617-enable-i2c-on-sa8255p-v7-1-ad736dbeab57@oss.qualcomm.com/ [2] https://git.codelinaro.org/clo/le/meta-qti-auto-kernel/-/blob/LY.AU.0.1.0.r1-16800-gen4meta.0/recipes-kernel/linux/files/usb/0014-PENDING-phy-qcom-snps-femto-v2-Add-support-for-SA825.patch Signed-off-by: Mattijs Korpershoek <mkorpershoek@kernel.org> --- Changes in v3: - Applied R-b from Krzysztof and Neil - Link to v2: https://patch.msgid.link/20260831-phy-qcom-snps-femto-v2-8255-v2-0-dc6197ffde1b@kernel.org Changes in v2: - Move 'core' as first domain, before 'transfer' (Krzysztof) - Reworded binding commit message to be more precise about the various domains ('core', 'transfer' and 'perf') (Krzysztof) - Link to v1: https://patch.msgid.link/20260730-phy-qcom-snps-femto-v2-8255-v1-0-8b8bf5105a68@kernel.org --- Mattijs Korpershoek (1): dt-bindings: phy: Add sa8255p high-speed USB PHY Sriram Dash (1): phy: qcom-snps-femto-v2: Add support for SA8255P .../bindings/phy/qcom,sa8255p-usb-hs-phy.yaml | 52 +++++++++ drivers/phy/qualcomm/phy-qcom-snps-femto-v2.c | 127 +++++++++++++++++++-- 2 files changed, 170 insertions(+), 9 deletions(-) --- base-commit: e30626823a406725ce29bc75cb8ec467d3e1e326 change-id: 20260729-phy-qcom-snps-femto-v2-8255-90ffe7674001 Best regards, -- Mattijs Korpershoek <mkorpershoek@kernel.org> -- linux-phy mailing list linux-phy@lists.infradead.org https://lists.infradead.org/mailman/listinfo/linux-phy ^ permalink raw reply [flat|nested] 10+ messages in thread
* [PATCH v3 1/2] dt-bindings: phy: Add sa8255p high-speed USB PHY 2026-10-02 9:41 ` Mattijs Korpershoek @ 2026-10-02 9:41 ` Mattijs Korpershoek -1 siblings, 0 replies; 10+ messages in thread From: Mattijs Korpershoek @ 2026-10-02 9:41 UTC (permalink / raw) To: Vinod Koul, Neil Armstrong, Rob Herring, Krzysztof Kozlowski, Conor Dooley, Philipp Zabel Cc: linux-arm-msm, linux-phy, devicetree, linux-kernel, Mattijs Korpershoek, Krzysztof Kozlowski SA8255p platform abstracts resources such as resets, clocks and regulators in firmware. The SCMI firmware exposes multiple protocols to control such resources which are identified by protocol_id. For this USB phy, 2 SCMI protocols are exposed by the firmware: * power domain management protocol (protocol_id=0x11) * performance domain management protocol (protocol_id=0x13) The power domain has 2 indices: 'core' and 'transfer'. * core controls the regulators, the clocks and the reset * transfer only controls the clocks For example, to power on/off the PHY, we should use the 'core' domain. To disable data transfer and keeping power enabled, we should use the 'transfer' domain. Add a new binding for the Qualcomm SA8255p Synopsys Femto High-Speed USB PHY V2 found in SA8255P. Note: the performance domain (0x13) exposes opaques values (0xa to 0x11) for which we don't have any information. Since it is not mandatory for the PHY to be functional, we have ommited it from the bindings. We can document it (and make them part of the dt ABI) once we have more information. Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com> Signed-off-by: Mattijs Korpershoek <mkorpershoek@kernel.org> --- .../bindings/phy/qcom,sa8255p-usb-hs-phy.yaml | 52 ++++++++++++++++++++++ 1 file changed, 52 insertions(+) diff --git a/Documentation/devicetree/bindings/phy/qcom,sa8255p-usb-hs-phy.yaml b/Documentation/devicetree/bindings/phy/qcom,sa8255p-usb-hs-phy.yaml new file mode 100644 index 000000000000..fff474a8345d --- /dev/null +++ b/Documentation/devicetree/bindings/phy/qcom,sa8255p-usb-hs-phy.yaml @@ -0,0 +1,52 @@ +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/phy/qcom,sa8255p-usb-hs-phy.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Qualcomm SA8255p Synopsys Femto High-Speed USB PHY V2 + +maintainers: + - Mattijs Korpershoek <mkorpershoek@kernel.org> + +properties: + compatible: + const: qcom,sa8255p-usb-hs-phy + + reg: + maxItems: 1 + + "#phy-cells": + const: 0 + + power-domains: + maxItems: 2 + + power-domain-names: + items: + - const: core + - const: transfer + +required: + - compatible + - reg + - "#phy-cells" + - power-domains + - power-domain-names + +additionalProperties: false + +examples: + - | + soc { + #address-cells = <2>; + #size-cells = <2>; + + phy@88e4000 { + compatible = "qcom,sa8255p-usb-hs-phy"; + reg = <0x0 0x088e4000 0x0 0x120>; + #phy-cells = <0>; + power-domains = <&scmi12_pd 1>, <&scmi12_pd 0>; + power-domain-names = "core", "transfer"; + }; + }; -- 2.55.0 ^ permalink raw reply related [flat|nested] 10+ messages in thread
* [PATCH v3 1/2] dt-bindings: phy: Add sa8255p high-speed USB PHY @ 2026-10-02 9:41 ` Mattijs Korpershoek 0 siblings, 0 replies; 10+ messages in thread From: Mattijs Korpershoek @ 2026-10-02 9:41 UTC (permalink / raw) To: Vinod Koul, Neil Armstrong, Rob Herring, Krzysztof Kozlowski, Conor Dooley, Philipp Zabel Cc: linux-arm-msm, linux-phy, devicetree, linux-kernel, Mattijs Korpershoek, Krzysztof Kozlowski SA8255p platform abstracts resources such as resets, clocks and regulators in firmware. The SCMI firmware exposes multiple protocols to control such resources which are identified by protocol_id. For this USB phy, 2 SCMI protocols are exposed by the firmware: * power domain management protocol (protocol_id=0x11) * performance domain management protocol (protocol_id=0x13) The power domain has 2 indices: 'core' and 'transfer'. * core controls the regulators, the clocks and the reset * transfer only controls the clocks For example, to power on/off the PHY, we should use the 'core' domain. To disable data transfer and keeping power enabled, we should use the 'transfer' domain. Add a new binding for the Qualcomm SA8255p Synopsys Femto High-Speed USB PHY V2 found in SA8255P. Note: the performance domain (0x13) exposes opaques values (0xa to 0x11) for which we don't have any information. Since it is not mandatory for the PHY to be functional, we have ommited it from the bindings. We can document it (and make them part of the dt ABI) once we have more information. Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com> Signed-off-by: Mattijs Korpershoek <mkorpershoek@kernel.org> --- .../bindings/phy/qcom,sa8255p-usb-hs-phy.yaml | 52 ++++++++++++++++++++++ 1 file changed, 52 insertions(+) diff --git a/Documentation/devicetree/bindings/phy/qcom,sa8255p-usb-hs-phy.yaml b/Documentation/devicetree/bindings/phy/qcom,sa8255p-usb-hs-phy.yaml new file mode 100644 index 000000000000..fff474a8345d --- /dev/null +++ b/Documentation/devicetree/bindings/phy/qcom,sa8255p-usb-hs-phy.yaml @@ -0,0 +1,52 @@ +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/phy/qcom,sa8255p-usb-hs-phy.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Qualcomm SA8255p Synopsys Femto High-Speed USB PHY V2 + +maintainers: + - Mattijs Korpershoek <mkorpershoek@kernel.org> + +properties: + compatible: + const: qcom,sa8255p-usb-hs-phy + + reg: + maxItems: 1 + + "#phy-cells": + const: 0 + + power-domains: + maxItems: 2 + + power-domain-names: + items: + - const: core + - const: transfer + +required: + - compatible + - reg + - "#phy-cells" + - power-domains + - power-domain-names + +additionalProperties: false + +examples: + - | + soc { + #address-cells = <2>; + #size-cells = <2>; + + phy@88e4000 { + compatible = "qcom,sa8255p-usb-hs-phy"; + reg = <0x0 0x088e4000 0x0 0x120>; + #phy-cells = <0>; + power-domains = <&scmi12_pd 1>, <&scmi12_pd 0>; + power-domain-names = "core", "transfer"; + }; + }; -- 2.55.0 -- linux-phy mailing list linux-phy@lists.infradead.org https://lists.infradead.org/mailman/listinfo/linux-phy ^ permalink raw reply related [flat|nested] 10+ messages in thread
* [PATCH v3 2/2] phy: qcom-snps-femto-v2: Add support for SA8255P 2026-10-02 9:41 ` Mattijs Korpershoek @ 2026-10-02 9:41 ` Mattijs Korpershoek -1 siblings, 0 replies; 10+ messages in thread From: Mattijs Korpershoek @ 2026-10-02 9:41 UTC (permalink / raw) To: Vinod Koul, Neil Armstrong, Rob Herring, Krzysztof Kozlowski, Conor Dooley, Philipp Zabel Cc: linux-arm-msm, linux-phy, devicetree, linux-kernel, Mattijs Korpershoek, Sriram Dash From: Sriram Dash <quic_sriramd@quicinc.com> The Qualcomm automotive SA8255p SoC relies on firmware to configure platform resources, including clocks, interconnects and TLMM. The driver requests resources operations over SCMI using power protocols. The SCMI power protocol enables or disables resources like clocks, interconnect paths, and TLMM (GPIOs) using runtime PM framework APIs, such as resume/suspend, to control power on/off. Power domain "core" controls the GDSC, resets, and TLMM (GPIOs) whereas power domain "transfer" controls clocks and interconnects. In this variant, two disjoint sets of resources are modeled against the power domain suppliers which can be turned on/off to achieve modeled device states. Two modeled low power states d1 and d3 are supported. transition: d0 <--> d3 :: both core and transfer suppliers transition: d0 <--> d1 :: only transfer supplier Signed-off-by: Sriram Dash <quic_sriramd@quicinc.com> Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org> Signed-off-by: Mattijs Korpershoek <mkorpershoek@kernel.org> --- drivers/phy/qualcomm/phy-qcom-snps-femto-v2.c | 127 ++++++++++++++++++++++++-- 1 file changed, 118 insertions(+), 9 deletions(-) diff --git a/drivers/phy/qualcomm/phy-qcom-snps-femto-v2.c b/drivers/phy/qualcomm/phy-qcom-snps-femto-v2.c index 980ad1fb1e2e..9fdf7ae681b6 100644 --- a/drivers/phy/qualcomm/phy-qcom-snps-femto-v2.c +++ b/drivers/phy/qualcomm/phy-qcom-snps-femto-v2.c @@ -12,6 +12,7 @@ #include <linux/of.h> #include <linux/phy/phy.h> #include <linux/platform_device.h> +#include <linux/pm_domain.h> #include <linux/regmap.h> #include <linux/regulator/consumer.h> #include <linux/reset.h> @@ -95,6 +96,7 @@ struct override_param_map { u8 table_size; u8 reg_offset; u8 param_mask; + bool fw_managed; }; struct phy_override_seq { @@ -121,6 +123,7 @@ struct phy_override_seq { * @phy_initialized: if PHY has been initialized correctly * @mode: contains the current mode the PHY is in * @update_seq_cfg: tuning parameters for phy init + * @pd_list: list of power domains associated with the device */ struct qcom_snps_hsphy { struct device *dev; @@ -136,8 +139,81 @@ struct qcom_snps_hsphy { bool phy_initialized; enum phy_mode mode; struct phy_override_seq update_seq_cfg[NUM_HSPHY_TUNING_PARAMS]; + + struct dev_pm_domain_list *pd_list; }; +static void qcom_snps_domain_detach(void *data) +{ + struct qcom_snps_hsphy *hsphy = data; + + dev_pm_domain_detach_list(hsphy->pd_list); +} + +static int qcom_snps_domain_attach(struct qcom_snps_hsphy *hsphy) +{ + struct dev_pm_domain_attach_data pd_data = { + .pd_flags = PD_FLAG_NO_DEV_LINK, + .pd_names = (const char*[]) { "core", "transfer" }, + .num_pd_names = 2, + }; + struct device *dev = hsphy->dev; + int ret; + + ret = dev_pm_domain_attach_list(dev, &pd_data, &hsphy->pd_list); + if (ret < 0) + return dev_err_probe(dev, ret, "domain attach failed\n"); + + return 0; +} + +/* d3_to_d0 transition by turning on all the suppliers */ +static int qcom_snps_d3_to_d0(struct qcom_snps_hsphy *hsphy) +{ + int ret; + + if (!hsphy->pd_list) + return 0; + + ret = pm_runtime_resume_and_get(hsphy->pd_list->pd_devs[0]); + if (ret) + return ret; + + ret = pm_runtime_resume_and_get(hsphy->pd_list->pd_devs[1]); + if (ret) + pm_runtime_put_sync(hsphy->pd_list->pd_devs[0]); + + return ret; +} + +/* d0_to_d3 transition by turning off all the suppliers */ +static void qcom_snps_d0_to_d3(struct qcom_snps_hsphy *hsphy) +{ + if (!hsphy->pd_list) + return; + + pm_runtime_put_sync(hsphy->pd_list->pd_devs[1]); + pm_runtime_put_sync(hsphy->pd_list->pd_devs[0]); +} + +/* d1_to_d0 transition by turning on the 'transfer' supplier */ +static int qcom_snps_d1_to_d0(struct qcom_snps_hsphy *hsphy) +{ + if (!hsphy->pd_list) + return 0; + + return pm_runtime_resume_and_get(hsphy->pd_list->pd_devs[1]); +} + +/* d0_to_d1 transition by turning off the 'transfer' supplier */ +static void qcom_snps_d0_to_d1(struct qcom_snps_hsphy *hsphy) +{ + if (!hsphy->pd_list) + return; + + pm_runtime_put_sync(hsphy->pd_list->pd_devs[1]); +} + static int qcom_snps_hsphy_clk_init(struct qcom_snps_hsphy *hsphy) { struct device *dev = hsphy->dev; @@ -196,6 +272,8 @@ static int qcom_snps_hsphy_suspend(struct qcom_snps_hsphy *hsphy) 0, USB2_AUTO_RESUME); } + qcom_snps_d0_to_d1(hsphy); + return 0; } @@ -203,7 +281,7 @@ static int qcom_snps_hsphy_resume(struct qcom_snps_hsphy *hsphy) { dev_dbg(&hsphy->phy->dev, "Resume QCOM SNPS PHY, mode\n"); - return 0; + return qcom_snps_d1_to_d0(hsphy); } static int __maybe_unused qcom_snps_hsphy_runtime_suspend(struct device *dev) @@ -316,6 +394,10 @@ static const struct override_param ls_fs_output_impedance_sc7280[] = { { 1310, 0 }, }; +static const struct override_param_map sa8255p_snps_hs_phy = { + .fw_managed = true, +}; + static const struct override_param_map sc7280_snps_7nm_phy[] = { { "qcom,hs-disconnect-bp", @@ -390,9 +472,15 @@ static int qcom_snps_hsphy_init(struct phy *phy) dev_vdbg(&phy->dev, "%s(): Initializing SNPS HS phy\n", __func__); + ret = qcom_snps_d3_to_d0(hsphy); + if (ret < 0) { + dev_err(hsphy->dev, "Failed to transition to d0 state\n"); + return ret; + } + ret = regulator_bulk_enable(ARRAY_SIZE(hsphy->vregs), hsphy->vregs); if (ret) - return ret; + goto transition_to_d3; ret = clk_bulk_prepare_enable(hsphy->num_clks, hsphy->clks); if (ret) { @@ -472,6 +560,8 @@ static int qcom_snps_hsphy_init(struct phy *phy) clk_bulk_disable_unprepare(hsphy->num_clks, hsphy->clks); poweroff_phy: regulator_bulk_disable(ARRAY_SIZE(hsphy->vregs), hsphy->vregs); +transition_to_d3: + qcom_snps_d0_to_d3(hsphy); return ret; } @@ -485,6 +575,8 @@ static int qcom_snps_hsphy_exit(struct phy *phy) regulator_bulk_disable(ARRAY_SIZE(hsphy->vregs), hsphy->vregs); hsphy->phy_initialized = false; + qcom_snps_d0_to_d3(hsphy); + return 0; } @@ -496,6 +588,10 @@ static const struct phy_ops qcom_snps_hsphy_gen_ops = { }; static const struct of_device_id qcom_snps_hsphy_of_match_table[] = { + { + .compatible = "qcom,sa8255p-usb-hs-phy", + .data = &sa8255p_snps_hs_phy, + }, { .compatible = "qcom,sm8150-usb-hs-phy", }, { .compatible = "qcom,usb-snps-hs-5nm-phy", }, { @@ -565,6 +661,7 @@ static int qcom_snps_hsphy_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct qcom_snps_hsphy *hsphy; + const struct override_param_map *cfg; struct phy_provider *phy_provider; struct phy *generic_phy; int ret, i; @@ -580,14 +677,26 @@ static int qcom_snps_hsphy_probe(struct platform_device *pdev) if (IS_ERR(hsphy->base)) return PTR_ERR(hsphy->base); - ret = qcom_snps_hsphy_clk_init(hsphy); - if (ret) - return dev_err_probe(dev, ret, "failed to initialize clocks\n"); + cfg = of_device_get_match_data(dev); + + if (cfg && cfg->fw_managed) { + ret = qcom_snps_domain_attach(hsphy); + if (ret) + return ret; + + ret = devm_add_action_or_reset(dev, qcom_snps_domain_detach, hsphy); + if (ret) + return ret; + } else { + ret = qcom_snps_hsphy_clk_init(hsphy); + if (ret) + return dev_err_probe(dev, ret, "failed to initialize clocks\n"); - hsphy->phy_reset = devm_reset_control_get_exclusive(&pdev->dev, NULL); - if (IS_ERR(hsphy->phy_reset)) { - dev_err(dev, "failed to get phy core reset\n"); - return PTR_ERR(hsphy->phy_reset); + hsphy->phy_reset = devm_reset_control_get_exclusive(&pdev->dev, NULL); + if (IS_ERR(hsphy->phy_reset)) { + dev_err(dev, "failed to get phy core reset\n"); + return PTR_ERR(hsphy->phy_reset); + } } num = ARRAY_SIZE(hsphy->vregs); -- 2.55.0 ^ permalink raw reply related [flat|nested] 10+ messages in thread
* [PATCH v3 2/2] phy: qcom-snps-femto-v2: Add support for SA8255P @ 2026-10-02 9:41 ` Mattijs Korpershoek 0 siblings, 0 replies; 10+ messages in thread From: Mattijs Korpershoek @ 2026-10-02 9:41 UTC (permalink / raw) To: Vinod Koul, Neil Armstrong, Rob Herring, Krzysztof Kozlowski, Conor Dooley, Philipp Zabel Cc: linux-arm-msm, linux-phy, devicetree, linux-kernel, Mattijs Korpershoek, Sriram Dash From: Sriram Dash <quic_sriramd@quicinc.com> The Qualcomm automotive SA8255p SoC relies on firmware to configure platform resources, including clocks, interconnects and TLMM. The driver requests resources operations over SCMI using power protocols. The SCMI power protocol enables or disables resources like clocks, interconnect paths, and TLMM (GPIOs) using runtime PM framework APIs, such as resume/suspend, to control power on/off. Power domain "core" controls the GDSC, resets, and TLMM (GPIOs) whereas power domain "transfer" controls clocks and interconnects. In this variant, two disjoint sets of resources are modeled against the power domain suppliers which can be turned on/off to achieve modeled device states. Two modeled low power states d1 and d3 are supported. transition: d0 <--> d3 :: both core and transfer suppliers transition: d0 <--> d1 :: only transfer supplier Signed-off-by: Sriram Dash <quic_sriramd@quicinc.com> Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org> Signed-off-by: Mattijs Korpershoek <mkorpershoek@kernel.org> --- drivers/phy/qualcomm/phy-qcom-snps-femto-v2.c | 127 ++++++++++++++++++++++++-- 1 file changed, 118 insertions(+), 9 deletions(-) diff --git a/drivers/phy/qualcomm/phy-qcom-snps-femto-v2.c b/drivers/phy/qualcomm/phy-qcom-snps-femto-v2.c index 980ad1fb1e2e..9fdf7ae681b6 100644 --- a/drivers/phy/qualcomm/phy-qcom-snps-femto-v2.c +++ b/drivers/phy/qualcomm/phy-qcom-snps-femto-v2.c @@ -12,6 +12,7 @@ #include <linux/of.h> #include <linux/phy/phy.h> #include <linux/platform_device.h> +#include <linux/pm_domain.h> #include <linux/regmap.h> #include <linux/regulator/consumer.h> #include <linux/reset.h> @@ -95,6 +96,7 @@ struct override_param_map { u8 table_size; u8 reg_offset; u8 param_mask; + bool fw_managed; }; struct phy_override_seq { @@ -121,6 +123,7 @@ struct phy_override_seq { * @phy_initialized: if PHY has been initialized correctly * @mode: contains the current mode the PHY is in * @update_seq_cfg: tuning parameters for phy init + * @pd_list: list of power domains associated with the device */ struct qcom_snps_hsphy { struct device *dev; @@ -136,8 +139,81 @@ struct qcom_snps_hsphy { bool phy_initialized; enum phy_mode mode; struct phy_override_seq update_seq_cfg[NUM_HSPHY_TUNING_PARAMS]; + + struct dev_pm_domain_list *pd_list; }; +static void qcom_snps_domain_detach(void *data) +{ + struct qcom_snps_hsphy *hsphy = data; + + dev_pm_domain_detach_list(hsphy->pd_list); +} + +static int qcom_snps_domain_attach(struct qcom_snps_hsphy *hsphy) +{ + struct dev_pm_domain_attach_data pd_data = { + .pd_flags = PD_FLAG_NO_DEV_LINK, + .pd_names = (const char*[]) { "core", "transfer" }, + .num_pd_names = 2, + }; + struct device *dev = hsphy->dev; + int ret; + + ret = dev_pm_domain_attach_list(dev, &pd_data, &hsphy->pd_list); + if (ret < 0) + return dev_err_probe(dev, ret, "domain attach failed\n"); + + return 0; +} + +/* d3_to_d0 transition by turning on all the suppliers */ +static int qcom_snps_d3_to_d0(struct qcom_snps_hsphy *hsphy) +{ + int ret; + + if (!hsphy->pd_list) + return 0; + + ret = pm_runtime_resume_and_get(hsphy->pd_list->pd_devs[0]); + if (ret) + return ret; + + ret = pm_runtime_resume_and_get(hsphy->pd_list->pd_devs[1]); + if (ret) + pm_runtime_put_sync(hsphy->pd_list->pd_devs[0]); + + return ret; +} + +/* d0_to_d3 transition by turning off all the suppliers */ +static void qcom_snps_d0_to_d3(struct qcom_snps_hsphy *hsphy) +{ + if (!hsphy->pd_list) + return; + + pm_runtime_put_sync(hsphy->pd_list->pd_devs[1]); + pm_runtime_put_sync(hsphy->pd_list->pd_devs[0]); +} + +/* d1_to_d0 transition by turning on the 'transfer' supplier */ +static int qcom_snps_d1_to_d0(struct qcom_snps_hsphy *hsphy) +{ + if (!hsphy->pd_list) + return 0; + + return pm_runtime_resume_and_get(hsphy->pd_list->pd_devs[1]); +} + +/* d0_to_d1 transition by turning off the 'transfer' supplier */ +static void qcom_snps_d0_to_d1(struct qcom_snps_hsphy *hsphy) +{ + if (!hsphy->pd_list) + return; + + pm_runtime_put_sync(hsphy->pd_list->pd_devs[1]); +} + static int qcom_snps_hsphy_clk_init(struct qcom_snps_hsphy *hsphy) { struct device *dev = hsphy->dev; @@ -196,6 +272,8 @@ static int qcom_snps_hsphy_suspend(struct qcom_snps_hsphy *hsphy) 0, USB2_AUTO_RESUME); } + qcom_snps_d0_to_d1(hsphy); + return 0; } @@ -203,7 +281,7 @@ static int qcom_snps_hsphy_resume(struct qcom_snps_hsphy *hsphy) { dev_dbg(&hsphy->phy->dev, "Resume QCOM SNPS PHY, mode\n"); - return 0; + return qcom_snps_d1_to_d0(hsphy); } static int __maybe_unused qcom_snps_hsphy_runtime_suspend(struct device *dev) @@ -316,6 +394,10 @@ static const struct override_param ls_fs_output_impedance_sc7280[] = { { 1310, 0 }, }; +static const struct override_param_map sa8255p_snps_hs_phy = { + .fw_managed = true, +}; + static const struct override_param_map sc7280_snps_7nm_phy[] = { { "qcom,hs-disconnect-bp", @@ -390,9 +472,15 @@ static int qcom_snps_hsphy_init(struct phy *phy) dev_vdbg(&phy->dev, "%s(): Initializing SNPS HS phy\n", __func__); + ret = qcom_snps_d3_to_d0(hsphy); + if (ret < 0) { + dev_err(hsphy->dev, "Failed to transition to d0 state\n"); + return ret; + } + ret = regulator_bulk_enable(ARRAY_SIZE(hsphy->vregs), hsphy->vregs); if (ret) - return ret; + goto transition_to_d3; ret = clk_bulk_prepare_enable(hsphy->num_clks, hsphy->clks); if (ret) { @@ -472,6 +560,8 @@ static int qcom_snps_hsphy_init(struct phy *phy) clk_bulk_disable_unprepare(hsphy->num_clks, hsphy->clks); poweroff_phy: regulator_bulk_disable(ARRAY_SIZE(hsphy->vregs), hsphy->vregs); +transition_to_d3: + qcom_snps_d0_to_d3(hsphy); return ret; } @@ -485,6 +575,8 @@ static int qcom_snps_hsphy_exit(struct phy *phy) regulator_bulk_disable(ARRAY_SIZE(hsphy->vregs), hsphy->vregs); hsphy->phy_initialized = false; + qcom_snps_d0_to_d3(hsphy); + return 0; } @@ -496,6 +588,10 @@ static const struct phy_ops qcom_snps_hsphy_gen_ops = { }; static const struct of_device_id qcom_snps_hsphy_of_match_table[] = { + { + .compatible = "qcom,sa8255p-usb-hs-phy", + .data = &sa8255p_snps_hs_phy, + }, { .compatible = "qcom,sm8150-usb-hs-phy", }, { .compatible = "qcom,usb-snps-hs-5nm-phy", }, { @@ -565,6 +661,7 @@ static int qcom_snps_hsphy_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct qcom_snps_hsphy *hsphy; + const struct override_param_map *cfg; struct phy_provider *phy_provider; struct phy *generic_phy; int ret, i; @@ -580,14 +677,26 @@ static int qcom_snps_hsphy_probe(struct platform_device *pdev) if (IS_ERR(hsphy->base)) return PTR_ERR(hsphy->base); - ret = qcom_snps_hsphy_clk_init(hsphy); - if (ret) - return dev_err_probe(dev, ret, "failed to initialize clocks\n"); + cfg = of_device_get_match_data(dev); + + if (cfg && cfg->fw_managed) { + ret = qcom_snps_domain_attach(hsphy); + if (ret) + return ret; + + ret = devm_add_action_or_reset(dev, qcom_snps_domain_detach, hsphy); + if (ret) + return ret; + } else { + ret = qcom_snps_hsphy_clk_init(hsphy); + if (ret) + return dev_err_probe(dev, ret, "failed to initialize clocks\n"); - hsphy->phy_reset = devm_reset_control_get_exclusive(&pdev->dev, NULL); - if (IS_ERR(hsphy->phy_reset)) { - dev_err(dev, "failed to get phy core reset\n"); - return PTR_ERR(hsphy->phy_reset); + hsphy->phy_reset = devm_reset_control_get_exclusive(&pdev->dev, NULL); + if (IS_ERR(hsphy->phy_reset)) { + dev_err(dev, "failed to get phy core reset\n"); + return PTR_ERR(hsphy->phy_reset); + } } num = ARRAY_SIZE(hsphy->vregs); -- 2.55.0 -- linux-phy mailing list linux-phy@lists.infradead.org https://lists.infradead.org/mailman/listinfo/linux-phy ^ permalink raw reply related [flat|nested] 10+ messages in thread
* Re: [PATCH v3 0/2] Add support for SA8255P in the phy-qcom-snps-femto-v2 phy driver 2026-10-02 9:41 ` Mattijs Korpershoek @ 2026-10-15 14:24 ` Mattijs Korpershoek -1 siblings, 0 replies; 10+ messages in thread From: Mattijs Korpershoek @ 2026-10-15 14:24 UTC (permalink / raw) To: Vinod Koul, Neil Armstrong, Rob Herring, Krzysztof Kozlowski, Conor Dooley, Philipp Zabel, Manivannan Sadhasivam Cc: linux-arm-msm, linux-phy, devicetree, linux-kernel, Krzysztof Kozlowski, Sriram Dash Hi Mani, On Fri, Oct 02, 2026 at 11:41, Mattijs Korpershoek <mkorpershoek@kernel.org> wrote: > The Qualcomm automotive SA8255p SoC relies on firmware to configure > platform resources, including clocks, interconnects and TLMM. > The driver requests resources operations over SCMI using power protocols. > > The SCMI power protocol enables or disables resources like clocks, > interconnect paths, and TLMM (GPIOs) using runtime PM framework APIs, > such as resume/suspend, to control power on/off. > > Power domain "core" controls the GDSC, resets, and TLMM (GPIOs) > whereas power domain "transfer" controls clocks and interconnects. > > Patch 1 adds the binding for sa8255p. Similarly to what has been done > for I2C [1], this is a separate binding. > > Patch 2 adds the driver change, which is based on a public vendor > patch from qualcomm [2]. > I did the following changes on top of that: > * Use devm_add_action_or_reset() for dev_pm_domain_detach_list() instead > of implementing a driver .remove() > * Changed power domain names to drop 'usb_' prefix > * Fixed various error handling paths > * Added suspend/resume support > > This has been tested on next-20260728 with a Ride4 SA8775P board that > has SCMI firmware (which is compatible). > > [1] https://lore.kernel.org/all/20260617-enable-i2c-on-sa8255p-v7-1-ad736dbeab57@oss.qualcomm.com/ > [2] https://git.codelinaro.org/clo/le/meta-qti-auto-kernel/-/blob/LY.AU.0.1.0.r1-16800-gen4meta.0/recipes-kernel/linux/files/usb/0014-PENDING-phy-qcom-snps-femto-v2-Add-support-for-SA825.patch > > Signed-off-by: Mattijs Korpershoek <mkorpershoek@kernel.org> I don't know what happened but somehow I did not add you in To/Cc using "b4 prep -c" I've talked to Vinod at plumbers and he told me that I should request some review on these phy patches. Could you have a look whenever you have some time? Thanks a lot for your help. Mattijs > --- > Changes in v3: > - Applied R-b from Krzysztof and Neil > - Link to v2: https://patch.msgid.link/20260831-phy-qcom-snps-femto-v2-8255-v2-0-dc6197ffde1b@kernel.org > > Changes in v2: > - Move 'core' as first domain, before 'transfer' (Krzysztof) > - Reworded binding commit message to be more precise about the various > domains ('core', 'transfer' and 'perf') (Krzysztof) > - Link to v1: https://patch.msgid.link/20260730-phy-qcom-snps-femto-v2-8255-v1-0-8b8bf5105a68@kernel.org > > --- > Mattijs Korpershoek (1): > dt-bindings: phy: Add sa8255p high-speed USB PHY > > Sriram Dash (1): > phy: qcom-snps-femto-v2: Add support for SA8255P > > .../bindings/phy/qcom,sa8255p-usb-hs-phy.yaml | 52 +++++++++ > drivers/phy/qualcomm/phy-qcom-snps-femto-v2.c | 127 +++++++++++++++++++-- > 2 files changed, 170 insertions(+), 9 deletions(-) > --- > base-commit: e30626823a406725ce29bc75cb8ec467d3e1e326 > change-id: 20260729-phy-qcom-snps-femto-v2-8255-90ffe7674001 > > Best regards, > -- > Mattijs Korpershoek <mkorpershoek@kernel.org> -- linux-phy mailing list linux-phy@lists.infradead.org https://lists.infradead.org/mailman/listinfo/linux-phy ^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH v3 0/2] Add support for SA8255P in the phy-qcom-snps-femto-v2 phy driver @ 2026-10-15 14:24 ` Mattijs Korpershoek 0 siblings, 0 replies; 10+ messages in thread From: Mattijs Korpershoek @ 2026-10-15 14:24 UTC (permalink / raw) To: Vinod Koul, Neil Armstrong, Rob Herring, Krzysztof Kozlowski, Conor Dooley, Philipp Zabel, Manivannan Sadhasivam Cc: linux-arm-msm, linux-phy, devicetree, linux-kernel, Krzysztof Kozlowski, Sriram Dash Hi Mani, On Fri, Oct 02, 2026 at 11:41, Mattijs Korpershoek <mkorpershoek@kernel.org> wrote: > The Qualcomm automotive SA8255p SoC relies on firmware to configure > platform resources, including clocks, interconnects and TLMM. > The driver requests resources operations over SCMI using power protocols. > > The SCMI power protocol enables or disables resources like clocks, > interconnect paths, and TLMM (GPIOs) using runtime PM framework APIs, > such as resume/suspend, to control power on/off. > > Power domain "core" controls the GDSC, resets, and TLMM (GPIOs) > whereas power domain "transfer" controls clocks and interconnects. > > Patch 1 adds the binding for sa8255p. Similarly to what has been done > for I2C [1], this is a separate binding. > > Patch 2 adds the driver change, which is based on a public vendor > patch from qualcomm [2]. > I did the following changes on top of that: > * Use devm_add_action_or_reset() for dev_pm_domain_detach_list() instead > of implementing a driver .remove() > * Changed power domain names to drop 'usb_' prefix > * Fixed various error handling paths > * Added suspend/resume support > > This has been tested on next-20260728 with a Ride4 SA8775P board that > has SCMI firmware (which is compatible). > > [1] https://lore.kernel.org/all/20260617-enable-i2c-on-sa8255p-v7-1-ad736dbeab57@oss.qualcomm.com/ > [2] https://git.codelinaro.org/clo/le/meta-qti-auto-kernel/-/blob/LY.AU.0.1.0.r1-16800-gen4meta.0/recipes-kernel/linux/files/usb/0014-PENDING-phy-qcom-snps-femto-v2-Add-support-for-SA825.patch > > Signed-off-by: Mattijs Korpershoek <mkorpershoek@kernel.org> I don't know what happened but somehow I did not add you in To/Cc using "b4 prep -c" I've talked to Vinod at plumbers and he told me that I should request some review on these phy patches. Could you have a look whenever you have some time? Thanks a lot for your help. Mattijs > --- > Changes in v3: > - Applied R-b from Krzysztof and Neil > - Link to v2: https://patch.msgid.link/20260831-phy-qcom-snps-femto-v2-8255-v2-0-dc6197ffde1b@kernel.org > > Changes in v2: > - Move 'core' as first domain, before 'transfer' (Krzysztof) > - Reworded binding commit message to be more precise about the various > domains ('core', 'transfer' and 'perf') (Krzysztof) > - Link to v1: https://patch.msgid.link/20260730-phy-qcom-snps-femto-v2-8255-v1-0-8b8bf5105a68@kernel.org > > --- > Mattijs Korpershoek (1): > dt-bindings: phy: Add sa8255p high-speed USB PHY > > Sriram Dash (1): > phy: qcom-snps-femto-v2: Add support for SA8255P > > .../bindings/phy/qcom,sa8255p-usb-hs-phy.yaml | 52 +++++++++ > drivers/phy/qualcomm/phy-qcom-snps-femto-v2.c | 127 +++++++++++++++++++-- > 2 files changed, 170 insertions(+), 9 deletions(-) > --- > base-commit: e30626823a406725ce29bc75cb8ec467d3e1e326 > change-id: 20260729-phy-qcom-snps-femto-v2-8255-90ffe7674001 > > Best regards, > -- > Mattijs Korpershoek <mkorpershoek@kernel.org> ^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH v3 0/2] Add support for SA8255P in the phy-qcom-snps-femto-v2 phy driver 2026-10-15 14:24 ` Mattijs Korpershoek @ 2026-10-15 15:15 ` Manivannan Sadhasivam -1 siblings, 0 replies; 10+ messages in thread From: Manivannan Sadhasivam @ 2026-10-15 15:15 UTC (permalink / raw) To: Mattijs Korpershoek Cc: Vinod Koul, Neil Armstrong, Rob Herring, Krzysztof Kozlowski, Conor Dooley, Philipp Zabel, linux-arm-msm, linux-phy, devicetree, linux-kernel, Krzysztof Kozlowski, Sriram Dash On Thu, Oct 15, 2026 at 04:24:03PM +0200, Mattijs Korpershoek wrote: > Hi Mani, > > On Fri, Oct 02, 2026 at 11:41, Mattijs Korpershoek <mkorpershoek@kernel.org> wrote: > > > The Qualcomm automotive SA8255p SoC relies on firmware to configure > > platform resources, including clocks, interconnects and TLMM. > > The driver requests resources operations over SCMI using power protocols. > > > > The SCMI power protocol enables or disables resources like clocks, > > interconnect paths, and TLMM (GPIOs) using runtime PM framework APIs, > > such as resume/suspend, to control power on/off. > > > > Power domain "core" controls the GDSC, resets, and TLMM (GPIOs) > > whereas power domain "transfer" controls clocks and interconnects. > > > > Patch 1 adds the binding for sa8255p. Similarly to what has been done > > for I2C [1], this is a separate binding. > > > > Patch 2 adds the driver change, which is based on a public vendor > > patch from qualcomm [2]. > > I did the following changes on top of that: > > * Use devm_add_action_or_reset() for dev_pm_domain_detach_list() instead > > of implementing a driver .remove() > > * Changed power domain names to drop 'usb_' prefix > > * Fixed various error handling paths > > * Added suspend/resume support > > > > This has been tested on next-20260728 with a Ride4 SA8775P board that > > has SCMI firmware (which is compatible). > > > > [1] https://lore.kernel.org/all/20260617-enable-i2c-on-sa8255p-v7-1-ad736dbeab57@oss.qualcomm.com/ > > [2] https://git.codelinaro.org/clo/le/meta-qti-auto-kernel/-/blob/LY.AU.0.1.0.r1-16800-gen4meta.0/recipes-kernel/linux/files/usb/0014-PENDING-phy-qcom-snps-femto-v2-Add-support-for-SA825.patch > > > > Signed-off-by: Mattijs Korpershoek <mkorpershoek@kernel.org> > > I don't know what happened but somehow I did not add you in To/Cc using > "b4 prep -c" > No worries. > I've talked to Vinod at plumbers and he told me that I should request > some review on these phy patches. > > Could you have a look whenever you have some time? > Sure thing. This series is on my queue. Will get to it very soon. - Mani -- மணிவண்ணன் சதாசிவம் -- linux-phy mailing list linux-phy@lists.infradead.org https://lists.infradead.org/mailman/listinfo/linux-phy ^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH v3 0/2] Add support for SA8255P in the phy-qcom-snps-femto-v2 phy driver @ 2026-10-15 15:15 ` Manivannan Sadhasivam 0 siblings, 0 replies; 10+ messages in thread From: Manivannan Sadhasivam @ 2026-10-15 15:15 UTC (permalink / raw) To: Mattijs Korpershoek Cc: Vinod Koul, Neil Armstrong, Rob Herring, Krzysztof Kozlowski, Conor Dooley, Philipp Zabel, linux-arm-msm, linux-phy, devicetree, linux-kernel, Krzysztof Kozlowski, Sriram Dash On Thu, Oct 15, 2026 at 04:24:03PM +0200, Mattijs Korpershoek wrote: > Hi Mani, > > On Fri, Oct 02, 2026 at 11:41, Mattijs Korpershoek <mkorpershoek@kernel.org> wrote: > > > The Qualcomm automotive SA8255p SoC relies on firmware to configure > > platform resources, including clocks, interconnects and TLMM. > > The driver requests resources operations over SCMI using power protocols. > > > > The SCMI power protocol enables or disables resources like clocks, > > interconnect paths, and TLMM (GPIOs) using runtime PM framework APIs, > > such as resume/suspend, to control power on/off. > > > > Power domain "core" controls the GDSC, resets, and TLMM (GPIOs) > > whereas power domain "transfer" controls clocks and interconnects. > > > > Patch 1 adds the binding for sa8255p. Similarly to what has been done > > for I2C [1], this is a separate binding. > > > > Patch 2 adds the driver change, which is based on a public vendor > > patch from qualcomm [2]. > > I did the following changes on top of that: > > * Use devm_add_action_or_reset() for dev_pm_domain_detach_list() instead > > of implementing a driver .remove() > > * Changed power domain names to drop 'usb_' prefix > > * Fixed various error handling paths > > * Added suspend/resume support > > > > This has been tested on next-20260728 with a Ride4 SA8775P board that > > has SCMI firmware (which is compatible). > > > > [1] https://lore.kernel.org/all/20260617-enable-i2c-on-sa8255p-v7-1-ad736dbeab57@oss.qualcomm.com/ > > [2] https://git.codelinaro.org/clo/le/meta-qti-auto-kernel/-/blob/LY.AU.0.1.0.r1-16800-gen4meta.0/recipes-kernel/linux/files/usb/0014-PENDING-phy-qcom-snps-femto-v2-Add-support-for-SA825.patch > > > > Signed-off-by: Mattijs Korpershoek <mkorpershoek@kernel.org> > > I don't know what happened but somehow I did not add you in To/Cc using > "b4 prep -c" > No worries. > I've talked to Vinod at plumbers and he told me that I should request > some review on these phy patches. > > Could you have a look whenever you have some time? > Sure thing. This series is on my queue. Will get to it very soon. - Mani -- மணிவண்ணன் சதாசிவம் ^ permalink raw reply [flat|nested] 10+ messages in thread
end of thread, other threads:[~2026-10-15 15:16 UTC | newest] Thread overview: 10+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2026-10-02 9:41 [PATCH v3 0/2] Add support for SA8255P in the phy-qcom-snps-femto-v2 phy driver Mattijs Korpershoek 2026-10-02 9:41 ` Mattijs Korpershoek 2026-10-02 9:41 ` [PATCH v3 1/2] dt-bindings: phy: Add sa8255p high-speed USB PHY Mattijs Korpershoek 2026-10-02 9:41 ` Mattijs Korpershoek 2026-10-02 9:41 ` [PATCH v3 2/2] phy: qcom-snps-femto-v2: Add support for SA8255P Mattijs Korpershoek 2026-10-02 9:41 ` Mattijs Korpershoek 2026-10-15 14:24 ` [PATCH v3 0/2] Add support for SA8255P in the phy-qcom-snps-femto-v2 phy driver Mattijs Korpershoek 2026-10-15 14:24 ` Mattijs Korpershoek 2026-10-15 15:15 ` Manivannan Sadhasivam 2026-10-15 15:15 ` Manivannan Sadhasivam
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