Hi sibis, thank you for the patch. I have a few questions and comments below. On Fri, 2018-03-02 at 14:53 +0530, sibis wrote: > Add reset controller driver for Qualcomm SDM845 SoC to > control reset signals provided by AOSS for Modem, Venus > ADSP, GPU, Camera, Wireless, Display subsystem > > Signed-off-by: sibis <sibis@xxxxxxxxxxxxxx> > --- > .../devicetree/bindings/reset/qcom,aoss-reset.txt | 54 +++++++ > drivers/reset/Kconfig | 10 ++ > drivers/reset/Makefile | 1 + > drivers/reset/reset-qcom-aoss.c | 161 +++++++++++++++++++++ > include/dt-bindings/reset/qcom,aoss-sdm845.h | 17 +++ > 5 files changed, 243 insertions(+) > create mode 100644 Documentation/devicetree/bindings/reset/qcom,aoss-reset.txt > create mode 100644 drivers/reset/reset-qcom-aoss.c > create mode 100644 include/dt-bindings/reset/qcom,aoss-sdm845.h > > diff --git a/Documentation/devicetree/bindings/reset/qcom,aoss-reset.txt b/Documentation/devicetree/bindings/reset/qcom,aoss-reset.txt > new file mode 100644 > index 0000000..5318e14 > --- /dev/null > +++ b/Documentation/devicetree/bindings/reset/qcom,aoss-reset.txt > @@ -0,0 +1,54 @@ > +Qualcomm AOSS Reset Controller > +====================================== > + > +This binding describes a reset-controller found on AOSS (Always on SubSysem) > +for Qualcomm SDM845 SoCs. > + > +Required properties: > +- compatible: > + Usage: required > + Value type: <string> > + Definition: must be: > + "qcom,aoss-reset-sdm845", "syscon" > + > +- reg: > + Usage: required > + Value type: <prop-encoded-array> > + Definition: must specify the base address and size of the > + syscon device. > + > + > +- #reset-cells: > + Usage: required > + Value type: <uint> > + Definition: must be 1; cell entry represents the reset index. > + > +example: > + > +aoss_reset: qcom,reset-controller@b2e0100 { > + compatible = "qcom,aoss-reset-sdm845", "syscon"; > + reg = <0xc2b0000 0x20004>; > + #reset-cells = <1>; > +}; > + > + > +Specifying reset lines connected to IP modules > +============================================== > + > +Device nodes that need access to reset lines should > +specify them as a reset phandle in their corresponding node as > +specified in reset.txt. > + > +Example: > + > + modem-pil@4080000 { > + ... > + > + resets = <&aoss_reset AOSS_CC_MSS_RESTART>; > + reset-names = "mss_restart"; > + > + ... > + }; > + > +For list of all valid reset indicies see > +<dt-bindings/reset/qcom,aoss-sdm845.h> > diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig > index 7fc7769..4b1da86 100644 > --- a/drivers/reset/Kconfig > +++ b/drivers/reset/Kconfig > @@ -81,6 +81,16 @@ config RESET_PISTACHIO > help > This enables the reset driver for ImgTec Pistachio SoCs. > > +config RESET_QCOM_AOSS > + bool "Qcom AOSS Reset Driver" > + depends on ARCH_QCOM || COMPILE_TEST Do all ARCH_QCOM have AOSS? If so, should this be enabled by default? > + select MFD_SYSCON > + help > + This enables the AOSS (Always On SubSystem) reset driver > + for Qcom SoCs. Say Y if you want to control reset signals Is Qcom and Qualcomm interchangeable? > + provided by AOSS for Modem, Venus, ADSP, GPU, Camera, > + Wireless, Display subsystem. Otherwise, say N. > + > config RESET_SIMPLE > bool "Simple Reset Controller Driver" if COMPILE_TEST > default ARCH_SOCFPGA || ARCH_STM32 || ARCH_STRATIX10 || ARCH_SUNXI || ARCH_ZX > diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile > index 132c24f..c30044a 100644 > --- a/drivers/reset/Makefile > +++ b/drivers/reset/Makefile > @@ -14,6 +14,7 @@ obj-$(CONFIG_RESET_LPC18XX) += reset-lpc18xx.o > obj-$(CONFIG_RESET_MESON) += reset-meson.o > obj-$(CONFIG_RESET_OXNAS) += reset-oxnas.o > obj-$(CONFIG_RESET_PISTACHIO) += reset-pistachio.o > +obj-$(CONFIG_RESET_QCOM_AOSS) += reset-qcom-aoss.o > obj-$(CONFIG_RESET_SIMPLE) += reset-simple.o > obj-$(CONFIG_RESET_SUNXI) += reset-sunxi.o > obj-$(CONFIG_RESET_TI_SCI) += reset-ti-sci.o > diff --git a/drivers/reset/reset-qcom-aoss.c b/drivers/reset/reset-qcom-aoss.c > new file mode 100644 > index 0000000..eb8c69b > --- /dev/null > +++ b/drivers/reset/reset-qcom-aoss.c > @@ -0,0 +1,161 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Copyright (C) 2018 The Linux Foundation. All rights reserved. > + */ > + > +#include <linux/mfd/syscon.h> > +#include <linux/module.h> > +#include <linux/platform_device.h> > +#include <linux/reset-controller.h> > +#include <linux/regmap.h> > +#include <linux/of_device.h> > +#include <dt-bindings/reset/qcom,aoss-sdm845.h> > + > +struct qcom_aoss_reset_map { > + unsigned int reg; > + u8 bit; > +}; > + > +struct qcom_aoss_desc { > + const struct regmap_config *config; > + const struct qcom_aoss_reset_map *resets; > + int delay; > + size_t num_resets; > +}; > + > +struct qcom_aoss_reset_data { > + struct reset_controller_dev rcdev; > + struct regmap *regmap; > + const struct qcom_aoss_desc *desc; > +}; > + > +static const struct regmap_config aoss_sdm845_regmap_config = { > + .name = "aoss-reset", > + .reg_bits = 32, > + .reg_stride = 4, > + .val_bits = 32, > + .max_register = 0x20000, > + .fast_io = true, > +}; > + > +static const struct qcom_aoss_reset_map aoss_sdm845_resets[] = { > + [AOSS_CC_MSS_RESTART] = { 0x0, 0 }, > + [AOSS_CC_CAMSS_RESTART] = { 0x1000, 0 }, > + [AOSS_CC_VENUS_RESTART] = { 0x2000, 0 }, > + [AOSS_CC_GPU_RESTART] = { 0x3000, 0 }, > + [AOSS_CC_DISPSS_RESTART] = { 0x4000, 0 }, > + [AOSS_CC_WCSS_RESTART] = { 0x10000, 0 }, > + [AOSS_CC_LPASS_RESTART] = { 0x20000, 0 }, > +}; > + > +static const struct qcom_aoss_desc aoss_sdm845_desc = { > + .config = &aoss_sdm845_regmap_config, > + .resets = aoss_sdm845_resets, > + /* Wait 6 32kHz sleep cycles for reset */ > + .delay = 200, > + .num_resets = ARRAY_SIZE(aoss_sdm845_resets), > +}; > + > +static struct qcom_aoss_reset_data *to_qcom_aoss_reset_data( > + struct reset_controller_dev *rcdev) > +{ > + return container_of(rcdev, struct qcom_aoss_reset_data, rcdev); > +} > + > +static int qcom_aoss_control_assert(struct reset_controller_dev *rcdev, > + unsigned long idx) > +{ > + struct qcom_aoss_reset_data *data = to_qcom_aoss_reset_data(rcdev); > + const struct qcom_aoss_reset_map *map = &data->desc->resets[idx]; > + > + if (idx >= rcdev->nr_resets) > + return -EINVAL; This check is not necessary. For all drivers that don't set of_xlate, the default of_reset_simple_xlate already makes sure no reset_control is ever returned with rstc->id >= rcdev->nr_resets. > + return regmap_update_bits(data->regmap, map->reg, > + BIT(map->bit), BIT(map->bit)); > +} > + > +static int qcom_aoss_control_deassert(struct reset_controller_dev *rcdev, > + unsigned long idx) > +{ > + struct qcom_aoss_reset_data *data = to_qcom_aoss_reset_data(rcdev); > + const struct qcom_aoss_reset_map *map = &data->desc->resets[idx]; > + > + if (idx >= rcdev->nr_resets) > + return -EINVAL; Same here. > + return regmap_update_bits(data->regmap, map->reg, BIT(map->bit), 0); > +} > + > +static int qcom_aoss_control_reset(struct reset_controller_dev *rcdev, > + unsigned long idx) > +{ > + struct qcom_aoss_reset_data *data = to_qcom_aoss_reset_data(rcdev); > + int ret; > + > + ret = rcdev->ops->assert(rcdev, idx); Don't use the ops function pointers here, just call qcom_aoss_control_assert directly. > + if (ret) > + return ret; > + > + udelay(data->desc->delay); > + > + ret = rcdev->ops->deassert(rcdev, idx); > + if (ret) > + return ret; > + > + return 0; This can be simplified to just return qcom_aoss_control_deassert(rcdev, idx); > +} > + > +static const struct reset_control_ops qcom_aoss_reset_ops = { > + .reset = qcom_aoss_control_reset, > + .assert = qcom_aoss_control_assert, > + .deassert = qcom_aoss_control_deassert, > +}; > + > +static int qcom_aoss_reset_probe(struct platform_device *pdev) > +{ > + struct qcom_aoss_reset_data *data; > + struct device *dev = &pdev->dev; > + const struct qcom_aoss_desc *desc; > + > + desc = of_device_get_match_data(&pdev->dev); You could use dev here instead of pdev->dev. > + if (!desc) > + return -EINVAL; > + > + data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); > + if (!data) > + return -ENOMEM; > + > + data->desc = desc; > + data->regmap = syscon_node_to_regmap(dev->of_node); > + if (IS_ERR(data->regmap)) { > + dev_err(dev, "Unable to get aoss-reset regmap"); > + return PTR_ERR(data->regmap); > + } > + regmap_attach_dev(dev, data->regmap, desc->config); > + > + data->rcdev.owner = THIS_MODULE; > + data->rcdev.ops = &qcom_aoss_reset_ops; > + data->rcdev.nr_resets = desc->num_resets; > + data->rcdev.of_node = pdev->dev.of_node; And here. > + return devm_reset_controller_register(&pdev->dev, &data->rcdev); And here. > +} > + > +static const struct of_device_id qcom_aoss_reset_of_match[] = { > + { .compatible = "qcom,aoss-reset-sdm845", .data = &aoss_sdm845_desc}, Consider adding a space between &aoss_sdm845_desc and } ... > + {} > +}; > + > +static struct platform_driver qcom_aoss_reset_driver = { > + .probe = qcom_aoss_reset_probe, > + .driver = { > + .name = "qcom_aoss_reset", ... and removing the superfluous space here. > + .of_match_table = qcom_aoss_reset_of_match, > + }, > +}; > + > +builtin_platform_driver(qcom_aoss_reset_driver); > + > +MODULE_DESCRIPTION("Qualcomm AOSS Reset Driver"); > +MODULE_LICENSE("GPL v2"); > diff --git a/include/dt-bindings/reset/qcom,aoss-sdm845.h b/include/dt-bindings/reset/qcom,aoss-sdm845.h > new file mode 100644 > index 0000000..e9b38fc > --- /dev/null > +++ b/include/dt-bindings/reset/qcom,aoss-sdm845.h > @@ -0,0 +1,17 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Copyright (C) 2018 The Linux Foundation. All rights reserved. > + */ > + > +#ifndef _DT_BINDINGS_RESET_AOSS_SDM_845_H > +#define _DT_BINDINGS_RESET_AOSS_SDM_845_H > + > +#define AOSS_CC_MSS_RESTART 0 > +#define AOSS_CC_CAMSS_RESTART 1 > +#define AOSS_CC_VENUS_RESTART 2 > +#define AOSS_CC_GPU_RESTART 3 > +#define AOSS_CC_DISPSS_RESTART 4 > +#define AOSS_CC_WCSS_RESTART 5 > +#define AOSS_CC_LPASS_RESTART 6 > + > +#endif regards Philipp -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html