From 41197eb5f993d5572ea533c9378c49ca81e24c8e Mon Sep 17 00:00:00 2001 From: Chen Wang Date: Tue, 30 Jan 2024 09:49:45 +0800 Subject: dt-bindings: reset: sophgo: support SG2042 Add bindings for the reset generator on the SOPHGO SG2042 RISC-V SoC. Signed-off-by: Chen Wang Reviewed-by: Krzysztof Kozlowski Reviewed-by: Inochi Amaoto Link: https://lore.kernel.org/r/35c348437b6e18972ccaf90d9c38040caccd1f11.1706577450.git.unicorn_wang@outlook.com Signed-off-by: Philipp Zabel --- .../bindings/reset/sophgo,sg2042-reset.yaml | 35 +++++++++ include/dt-bindings/reset/sophgo,sg2042-reset.h | 87 ++++++++++++++++++++++ 2 files changed, 122 insertions(+) create mode 100644 Documentation/devicetree/bindings/reset/sophgo,sg2042-reset.yaml create mode 100644 include/dt-bindings/reset/sophgo,sg2042-reset.h diff --git a/Documentation/devicetree/bindings/reset/sophgo,sg2042-reset.yaml b/Documentation/devicetree/bindings/reset/sophgo,sg2042-reset.yaml new file mode 100644 index 000000000000..76e1931f0908 --- /dev/null +++ b/Documentation/devicetree/bindings/reset/sophgo,sg2042-reset.yaml @@ -0,0 +1,35 @@ +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/reset/sophgo,sg2042-reset.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Sophgo SG2042 SoC Reset Controller + +maintainers: + - Chen Wang + +properties: + compatible: + const: sophgo,sg2042-reset + + reg: + maxItems: 1 + + "#reset-cells": + const: 1 + +required: + - compatible + - reg + - "#reset-cells" + +additionalProperties: false + +examples: + - | + rstgen: reset-controller@c00 { + compatible = "sophgo,sg2042-reset"; + reg = <0xc00 0xc>; + #reset-cells = <1>; + }; diff --git a/include/dt-bindings/reset/sophgo,sg2042-reset.h b/include/dt-bindings/reset/sophgo,sg2042-reset.h new file mode 100644 index 000000000000..9ab0980625c1 --- /dev/null +++ b/include/dt-bindings/reset/sophgo,sg2042-reset.h @@ -0,0 +1,87 @@ +/* SPDX-License-Identifier: GPL-2.0 OR BSD-2-Clause */ +/* + * Copyright (C) 2023 Sophgo Technology Inc. All rights reserved. + */ + +#ifndef __DT_BINDINGS_RESET_SOPHGO_SG2042_H_ +#define __DT_BINDINGS_RESET_SOPHGO_SG2042_H_ + +#define RST_MAIN_AP 0 +#define RST_RISCV_CPU 1 +#define RST_RISCV_LOW_SPEED_LOGIC 2 +#define RST_RISCV_CMN 3 +#define RST_HSDMA 4 +#define RST_SYSDMA 5 +#define RST_EFUSE0 6 +#define RST_EFUSE1 7 +#define RST_RTC 8 +#define RST_TIMER 9 +#define RST_WDT 10 +#define RST_AHB_ROM0 11 +#define RST_AHB_ROM1 12 +#define RST_I2C0 13 +#define RST_I2C1 14 +#define RST_I2C2 15 +#define RST_I2C3 16 +#define RST_GPIO0 17 +#define RST_GPIO1 18 +#define RST_GPIO2 19 +#define RST_PWM 20 +#define RST_AXI_SRAM0 21 +#define RST_AXI_SRAM1 22 +#define RST_SF0 23 +#define RST_SF1 24 +#define RST_LPC 25 +#define RST_ETH0 26 +#define RST_EMMC 27 +#define RST_SD 28 +#define RST_UART0 29 +#define RST_UART1 30 +#define RST_UART2 31 +#define RST_UART3 32 +#define RST_SPI0 33 +#define RST_SPI1 34 +#define RST_DBG_I2C 35 +#define RST_PCIE0 36 +#define RST_PCIE1 37 +#define RST_DDR0 38 +#define RST_DDR1 39 +#define RST_DDR2 40 +#define RST_DDR3 41 +#define RST_FAU0 42 +#define RST_FAU1 43 +#define RST_FAU2 44 +#define RST_RXU0 45 +#define RST_RXU1 46 +#define RST_RXU2 47 +#define RST_RXU3 48 +#define RST_RXU4 49 +#define RST_RXU5 50 +#define RST_RXU6 51 +#define RST_RXU7 52 +#define RST_RXU8 53 +#define RST_RXU9 54 +#define RST_RXU10 55 +#define RST_RXU11 56 +#define RST_RXU12 57 +#define RST_RXU13 58 +#define RST_RXU14 59 +#define RST_RXU15 60 +#define RST_RXU16 61 +#define RST_RXU17 62 +#define RST_RXU18 63 +#define RST_RXU19 64 +#define RST_RXU20 65 +#define RST_RXU21 66 +#define RST_RXU22 67 +#define RST_RXU23 68 +#define RST_RXU24 69 +#define RST_RXU25 70 +#define RST_RXU26 71 +#define RST_RXU27 72 +#define RST_RXU28 73 +#define RST_RXU29 74 +#define RST_RXU30 75 +#define RST_RXU31 76 + +#endif /* __DT_BINDINGS_RESET_SOPHGO_SG2042_H_ */ -- cgit From a6166a4da5e46a01e6ad5b0bb079d77ac653f594 Mon Sep 17 00:00:00 2001 From: Chen Wang Date: Tue, 30 Jan 2024 09:50:08 +0800 Subject: reset: simple: add support for Sophgo SG2042 Reuse reset-simple driver for the Sophgo SG2042 reset generator. Signed-off-by: Chen Wang Reviewed-by: Philipp Zabel Link: https://lore.kernel.org/r/1cfd7b3ba447942784c4f7aa595e962399e9f617.1706577450.git.unicorn_wang@outlook.com Signed-off-by: Philipp Zabel --- drivers/reset/Kconfig | 3 ++- drivers/reset/reset-simple.c | 2 ++ 2 files changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig index ccd59ddd7610..2034f69d5953 100644 --- a/drivers/reset/Kconfig +++ b/drivers/reset/Kconfig @@ -213,7 +213,7 @@ config RESET_SCMI config RESET_SIMPLE bool "Simple Reset Controller Driver" if COMPILE_TEST || EXPERT - default ARCH_ASPEED || ARCH_BCMBCA || ARCH_BITMAIN || ARCH_REALTEK || ARCH_STM32 || (ARCH_INTEL_SOCFPGA && ARM64) || ARCH_SUNXI || ARC + default ARCH_ASPEED || ARCH_BCMBCA || ARCH_BITMAIN || ARCH_REALTEK || ARCH_SOPHGO || ARCH_STM32 || (ARCH_INTEL_SOCFPGA && ARM64) || ARCH_SUNXI || ARC depends on HAS_IOMEM help This enables a simple reset controller driver for reset lines that @@ -228,6 +228,7 @@ config RESET_SIMPLE - RCC reset controller in STM32 MCUs - Allwinner SoCs - SiFive FU740 SoCs + - Sophgo SoCs config RESET_SOCFPGA bool "SoCFPGA Reset Driver" if COMPILE_TEST && (!ARM || !ARCH_INTEL_SOCFPGA) diff --git a/drivers/reset/reset-simple.c b/drivers/reset/reset-simple.c index 818cabcc9fb7..276067839830 100644 --- a/drivers/reset/reset-simple.c +++ b/drivers/reset/reset-simple.c @@ -151,6 +151,8 @@ static const struct of_device_id reset_simple_dt_ids[] = { { .compatible = "snps,dw-high-reset" }, { .compatible = "snps,dw-low-reset", .data = &reset_simple_active_low }, + { .compatible = "sophgo,sg2042-reset", + .data = &reset_simple_active_low }, { /* sentinel */ }, }; -- cgit From 26ea8511c849f9fea325bcdbd8b41ea031a53afe Mon Sep 17 00:00:00 2001 From: Krzysztof Kozlowski Date: Mon, 29 Jan 2024 12:52:11 +0100 Subject: of: Add of_phandle_args_equal() helper Add a helper comparing two "struct of_phandle_args" to avoid reinventing the wheel. Reviewed-by: Philipp Zabel Acked-by: Rob Herring Signed-off-by: Krzysztof Kozlowski Link: https://lore.kernel.org/r/20240129115216.96479-2-krzysztof.kozlowski@linaro.org Signed-off-by: Philipp Zabel --- include/linux/of.h | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/include/linux/of.h b/include/linux/of.h index 6a9ddf20e79a..85bcc05b278d 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -1065,6 +1065,22 @@ static inline int of_parse_phandle_with_optional_args(const struct device_node * 0, index, out_args); } +/** + * of_phandle_args_equal() - Compare two of_phandle_args + * @a1: First of_phandle_args to compare + * @a2: Second of_phandle_args to compare + * + * Return: True if a1 and a2 are the same (same node pointer, same phandle + * args), false otherwise. + */ +static inline bool of_phandle_args_equal(const struct of_phandle_args *a1, + const struct of_phandle_args *a2) +{ + return a1->np == a2->np && + a1->args_count == a2->args_count && + !memcmp(a1->args, a2->args, sizeof(a1->args[0]) * a1->args_count); +} + /** * of_property_count_u8_elems - Count the number of u8 elements in a property * -- cgit From 0f28982835c29752cdb657f1f8316b2ea42c407a Mon Sep 17 00:00:00 2001 From: Krzysztof Kozlowski Date: Mon, 29 Jan 2024 12:52:12 +0100 Subject: cpufreq: do not open-code of_phandle_args_equal() Use newly added of_phandle_args_equal() helper to compare two of_phandle_args. Acked-by: Viresh Kumar Reviewed-by: Philipp Zabel Signed-off-by: Krzysztof Kozlowski Link: https://lore.kernel.org/r/20240129115216.96479-3-krzysztof.kozlowski@linaro.org Signed-off-by: Philipp Zabel --- include/linux/cpufreq.h | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index afda5f24d3dd..3cd06dafb04b 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -1149,8 +1149,7 @@ static inline int of_perf_domain_get_sharing_cpumask(int pcpu, const char *list_ if (ret < 0) continue; - if (pargs->np == args.np && pargs->args_count == args.args_count && - !memcmp(pargs->args, args.args, sizeof(args.args[0]) * args.args_count)) + if (of_phandle_args_equal(pargs, &args)) cpumask_set_cpu(cpu, cpumask); of_node_put(args.np); -- cgit From cee544a40e4426040946e685988b1489f13e6600 Mon Sep 17 00:00:00 2001 From: Krzysztof Kozlowski Date: Mon, 29 Jan 2024 12:52:13 +0100 Subject: reset: gpio: Add GPIO-based reset controller Add a simple driver to control GPIO-based resets using the reset controller API for the cases when the GPIOs are shared and reset should be coordinated. The driver is expected to be used by reset core framework for ad-hoc reset controllers. Cc: Bartosz Golaszewski Cc: Chris Packham Cc: Sean Anderson Reviewed-by: Bartosz Golaszewski Reviewed-by: Philipp Zabel Signed-off-by: Krzysztof Kozlowski Link: https://lore.kernel.org/r/20240129115216.96479-4-krzysztof.kozlowski@linaro.org Signed-off-by: Philipp Zabel --- MAINTAINERS | 5 ++ drivers/reset/Kconfig | 9 ++++ drivers/reset/Makefile | 1 + drivers/reset/reset-gpio.c | 119 +++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 134 insertions(+) create mode 100644 drivers/reset/reset-gpio.c diff --git a/MAINTAINERS b/MAINTAINERS index 9ed4d3868539..11a014577d0d 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -8911,6 +8911,11 @@ F: Documentation/i2c/muxes/i2c-mux-gpio.rst F: drivers/i2c/muxes/i2c-mux-gpio.c F: include/linux/platform_data/i2c-mux-gpio.h +GENERIC GPIO RESET DRIVER +M: Krzysztof Kozlowski +S: Maintained +F: drivers/reset/reset-gpio.c + GENERIC HDLC (WAN) DRIVERS M: Krzysztof Halasa S: Maintained diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig index 2034f69d5953..85b27c42cf65 100644 --- a/drivers/reset/Kconfig +++ b/drivers/reset/Kconfig @@ -66,6 +66,15 @@ config RESET_BRCMSTB_RESCAL This enables the RESCAL reset controller for SATA, PCIe0, or PCIe1 on BCM7216. +config RESET_GPIO + tristate "GPIO reset controller" + help + This enables a generic reset controller for resets attached via + GPIOs. Typically for OF platforms this driver expects "reset-gpios" + property. + + If compiled as module, it will be called reset-gpio. + config RESET_HSDK bool "Synopsys HSDK Reset Driver" depends on HAS_IOMEM diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile index 8270da8a4baa..fd8b49fa46fc 100644 --- a/drivers/reset/Makefile +++ b/drivers/reset/Makefile @@ -11,6 +11,7 @@ obj-$(CONFIG_RESET_BCM6345) += reset-bcm6345.o obj-$(CONFIG_RESET_BERLIN) += reset-berlin.o obj-$(CONFIG_RESET_BRCMSTB) += reset-brcmstb.o obj-$(CONFIG_RESET_BRCMSTB_RESCAL) += reset-brcmstb-rescal.o +obj-$(CONFIG_RESET_GPIO) += reset-gpio.o obj-$(CONFIG_RESET_HSDK) += reset-hsdk.o obj-$(CONFIG_RESET_IMX7) += reset-imx7.o obj-$(CONFIG_RESET_INTEL_GW) += reset-intel-gw.o diff --git a/drivers/reset/reset-gpio.c b/drivers/reset/reset-gpio.c new file mode 100644 index 000000000000..2290b25b6703 --- /dev/null +++ b/drivers/reset/reset-gpio.c @@ -0,0 +1,119 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include +#include +#include +#include +#include +#include + +struct reset_gpio_priv { + struct reset_controller_dev rc; + struct gpio_desc *reset; +}; + +static inline struct reset_gpio_priv +*rc_to_reset_gpio(struct reset_controller_dev *rc) +{ + return container_of(rc, struct reset_gpio_priv, rc); +} + +static int reset_gpio_assert(struct reset_controller_dev *rc, unsigned long id) +{ + struct reset_gpio_priv *priv = rc_to_reset_gpio(rc); + + gpiod_set_value_cansleep(priv->reset, 1); + + return 0; +} + +static int reset_gpio_deassert(struct reset_controller_dev *rc, + unsigned long id) +{ + struct reset_gpio_priv *priv = rc_to_reset_gpio(rc); + + gpiod_set_value_cansleep(priv->reset, 0); + + return 0; +} + +static int reset_gpio_status(struct reset_controller_dev *rc, unsigned long id) +{ + struct reset_gpio_priv *priv = rc_to_reset_gpio(rc); + + return gpiod_get_value_cansleep(priv->reset); +} + +static const struct reset_control_ops reset_gpio_ops = { + .assert = reset_gpio_assert, + .deassert = reset_gpio_deassert, + .status = reset_gpio_status, +}; + +static int reset_gpio_of_xlate(struct reset_controller_dev *rcdev, + const struct of_phandle_args *reset_spec) +{ + return reset_spec->args[0]; +} + +static void reset_gpio_of_node_put(void *data) +{ + of_node_put(data); +} + +static int reset_gpio_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct of_phandle_args *platdata = dev_get_platdata(dev); + struct reset_gpio_priv *priv; + int ret; + + if (!platdata) + return -EINVAL; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + platform_set_drvdata(pdev, &priv->rc); + + priv->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH); + if (IS_ERR(priv->reset)) + return dev_err_probe(dev, PTR_ERR(priv->reset), + "Could not get reset gpios\n"); + + priv->rc.ops = &reset_gpio_ops; + priv->rc.owner = THIS_MODULE; + priv->rc.dev = dev; + priv->rc.of_args = platdata; + ret = devm_add_action_or_reset(dev, reset_gpio_of_node_put, + priv->rc.of_node); + if (ret) + return ret; + + /* Cells to match GPIO specifier, but it's not really used */ + priv->rc.of_reset_n_cells = 2; + priv->rc.of_xlate = reset_gpio_of_xlate; + priv->rc.nr_resets = 1; + + return devm_reset_controller_register(dev, &priv->rc); +} + +static const struct platform_device_id reset_gpio_ids[] = { + { .name = "reset-gpio", }, + {} +}; +MODULE_DEVICE_TABLE(platform, reset_gpio_ids); + +static struct platform_driver reset_gpio_driver = { + .probe = reset_gpio_probe, + .id_table = reset_gpio_ids, + .driver = { + .name = "reset-gpio", + }, +}; +module_platform_driver(reset_gpio_driver); + +MODULE_AUTHOR("Krzysztof Kozlowski "); +MODULE_DESCRIPTION("Generic GPIO reset driver"); +MODULE_LICENSE("GPL"); -- cgit From c721f189e89c0d4db119d7bb2b46768d0fb5f6b1 Mon Sep 17 00:00:00 2001 From: Krzysztof Kozlowski Date: Mon, 29 Jan 2024 12:52:14 +0100 Subject: reset: Instantiate reset GPIO controller for shared reset-gpios Devices sharing a reset GPIO could use the reset framework for coordinated handling of that shared GPIO line. We have several cases of such needs, at least for Devicetree-based platforms. If Devicetree-based device requests a reset line, while "resets" Devicetree property is missing but there is a "reset-gpios" one, instantiate a new "reset-gpio" platform device which will handle such reset line. This allows seamless handling of such shared reset-gpios without need of changing Devicetree binding [1]. To avoid creating multiple "reset-gpio" platform devices, store the Devicetree "reset-gpios" GPIO specifiers used for new devices on a linked list. Later such Devicetree GPIO specifier (phandle to GPIO controller, GPIO number and GPIO flags) is used to check if reset controller for given GPIO was already registered. If two devices have conflicting "reset-gpios" property, e.g. with different ACTIVE_xxx flags, this would allow to spawn two separate "reset-gpio" devices, where the second would fail probing on busy GPIO request. Link: https://lore.kernel.org/all/YXi5CUCEi7YmNxXM@robh.at.kernel.org/ [1] Cc: Bartosz Golaszewski Cc: Chris Packham Cc: Sean Anderson Reviewed-by: Philipp Zabel Signed-off-by: Krzysztof Kozlowski Acked-by: Bartosz Golaszewski Acked-by: Linus Walleij Link: https://lore.kernel.org/r/20240129115216.96479-5-krzysztof.kozlowski@linaro.org Signed-off-by: Philipp Zabel --- drivers/reset/core.c | 224 ++++++++++++++++++++++++++++++++++++--- include/linux/reset-controller.h | 4 + 2 files changed, 215 insertions(+), 13 deletions(-) diff --git a/drivers/reset/core.c b/drivers/reset/core.c index 4d5a78d3c085..dba74e857be6 100644 --- a/drivers/reset/core.c +++ b/drivers/reset/core.c @@ -5,14 +5,19 @@ * Copyright 2013 Philipp Zabel, Pengutronix */ #include +#include #include #include #include #include #include +#include +#include +#include #include #include #include +#include #include #include #include @@ -23,6 +28,11 @@ static LIST_HEAD(reset_controller_list); static DEFINE_MUTEX(reset_lookup_mutex); static LIST_HEAD(reset_lookup_list); +/* Protects reset_gpio_lookup_list */ +static DEFINE_MUTEX(reset_gpio_lookup_mutex); +static LIST_HEAD(reset_gpio_lookup_list); +static DEFINE_IDA(reset_gpio_ida); + /** * struct reset_control - a reset control * @rcdev: a pointer to the reset controller device @@ -63,6 +73,16 @@ struct reset_control_array { struct reset_control *rstc[] __counted_by(num_rstcs); }; +/** + * struct reset_gpio_lookup - lookup key for ad-hoc created reset-gpio devices + * @of_args: phandle to the reset controller with all the args like GPIO number + * @list: list entry for the reset_gpio_lookup_list + */ +struct reset_gpio_lookup { + struct of_phandle_args of_args; + struct list_head list; +}; + static const char *rcdev_name(struct reset_controller_dev *rcdev) { if (rcdev->dev) @@ -71,6 +91,9 @@ static const char *rcdev_name(struct reset_controller_dev *rcdev) if (rcdev->of_node) return rcdev->of_node->full_name; + if (rcdev->of_args) + return rcdev->of_args->np->full_name; + return NULL; } @@ -99,6 +122,9 @@ static int of_reset_simple_xlate(struct reset_controller_dev *rcdev, */ int reset_controller_register(struct reset_controller_dev *rcdev) { + if (rcdev->of_node && rcdev->of_args) + return -EINVAL; + if (!rcdev->of_xlate) { rcdev->of_reset_n_cells = 1; rcdev->of_xlate = of_reset_simple_xlate; @@ -813,12 +839,171 @@ static void __reset_control_put_internal(struct reset_control *rstc) kref_put(&rstc->refcnt, __reset_control_release); } +static int __reset_add_reset_gpio_lookup(int id, struct device_node *np, + unsigned int gpio, + unsigned int of_flags) +{ + const struct fwnode_handle *fwnode = of_fwnode_handle(np); + unsigned int lookup_flags; + const char *label_tmp; + + /* + * Later we map GPIO flags between OF and Linux, however not all + * constants from include/dt-bindings/gpio/gpio.h and + * include/linux/gpio/machine.h match each other. + */ + if (of_flags > GPIO_ACTIVE_LOW) { + pr_err("reset-gpio code does not support GPIO flags %u for GPIO %u\n", + of_flags, gpio); + return -EINVAL; + } + + struct gpio_device *gdev __free(gpio_device_put) = gpio_device_find_by_fwnode(fwnode); + if (!gdev) + return -EPROBE_DEFER; + + label_tmp = gpio_device_get_label(gdev); + if (!label_tmp) + return -EINVAL; + + char *label __free(kfree) = kstrdup(label_tmp, GFP_KERNEL); + if (!label) + return -ENOMEM; + + /* Size: one lookup entry plus sentinel */ + struct gpiod_lookup_table *lookup __free(kfree) = kzalloc(struct_size(lookup, table, 2), + GFP_KERNEL); + if (!lookup) + return -ENOMEM; + + lookup->dev_id = kasprintf(GFP_KERNEL, "reset-gpio.%d", id); + if (!lookup->dev_id) + return -ENOMEM; + + lookup_flags = GPIO_PERSISTENT; + lookup_flags |= of_flags & GPIO_ACTIVE_LOW; + lookup->table[0] = GPIO_LOOKUP(no_free_ptr(label), gpio, "reset", + lookup_flags); + + /* Not freed on success, because it is persisent subsystem data. */ + gpiod_add_lookup_table(no_free_ptr(lookup)); + + return 0; +} + +/* + * @args: phandle to the GPIO provider with all the args like GPIO number + */ +static int __reset_add_reset_gpio_device(const struct of_phandle_args *args) +{ + struct reset_gpio_lookup *rgpio_dev; + struct platform_device *pdev; + int id, ret; + + /* + * Currently only #gpio-cells=2 is supported with the meaning of: + * args[0]: GPIO number + * args[1]: GPIO flags + * TODO: Handle other cases. + */ + if (args->args_count != 2) + return -ENOENT; + + /* + * Registering reset-gpio device might cause immediate + * bind, resulting in its probe() registering new reset controller thus + * taking reset_list_mutex lock via reset_controller_register(). + */ + lockdep_assert_not_held(&reset_list_mutex); + + mutex_lock(&reset_gpio_lookup_mutex); + + list_for_each_entry(rgpio_dev, &reset_gpio_lookup_list, list) { + if (args->np == rgpio_dev->of_args.np) { + if (of_phandle_args_equal(args, &rgpio_dev->of_args)) + goto out; /* Already on the list, done */ + } + } + + id = ida_alloc(&reset_gpio_ida, GFP_KERNEL); + if (id < 0) { + ret = id; + goto err_unlock; + } + + /* Not freed on success, because it is persisent subsystem data. */ + rgpio_dev = kzalloc(sizeof(*rgpio_dev), GFP_KERNEL); + if (!rgpio_dev) { + ret = -ENOMEM; + goto err_ida_free; + } + + ret = __reset_add_reset_gpio_lookup(id, args->np, args->args[0], + args->args[1]); + if (ret < 0) + goto err_kfree; + + rgpio_dev->of_args = *args; + /* + * We keep the device_node reference, but of_args.np is put at the end + * of __of_reset_control_get(), so get it one more time. + * Hold reference as long as rgpio_dev memory is valid. + */ + of_node_get(rgpio_dev->of_args.np); + pdev = platform_device_register_data(NULL, "reset-gpio", id, + &rgpio_dev->of_args, + sizeof(rgpio_dev->of_args)); + ret = PTR_ERR_OR_ZERO(pdev); + if (ret) + goto err_put; + + list_add(&rgpio_dev->list, &reset_gpio_lookup_list); + +out: + mutex_unlock(&reset_gpio_lookup_mutex); + + return 0; + +err_put: + of_node_put(rgpio_dev->of_args.np); +err_kfree: + kfree(rgpio_dev); +err_ida_free: + ida_free(&reset_gpio_ida, id); +err_unlock: + mutex_unlock(&reset_gpio_lookup_mutex); + + return ret; +} + +static struct reset_controller_dev *__reset_find_rcdev(const struct of_phandle_args *args, + bool gpio_fallback) +{ + struct reset_controller_dev *rcdev; + + lockdep_assert_held(&reset_list_mutex); + + list_for_each_entry(rcdev, &reset_controller_list, list) { + if (gpio_fallback) { + if (rcdev->of_args && of_phandle_args_equal(args, + rcdev->of_args)) + return rcdev; + } else { + if (args->np == rcdev->of_node) + return rcdev; + } + } + + return NULL; +} + struct reset_control * __of_reset_control_get(struct device_node *node, const char *id, int index, bool shared, bool optional, bool acquired) { + bool gpio_fallback = false; struct reset_control *rstc; - struct reset_controller_dev *r, *rcdev; + struct reset_controller_dev *rcdev; struct of_phandle_args args; int rstc_id; int ret; @@ -839,39 +1024,52 @@ __of_reset_control_get(struct device_node *node, const char *id, int index, index, &args); if (ret == -EINVAL) return ERR_PTR(ret); - if (ret) - return optional ? NULL : ERR_PTR(ret); + if (ret) { + if (!IS_ENABLED(CONFIG_RESET_GPIO)) + return optional ? NULL : ERR_PTR(ret); - mutex_lock(&reset_list_mutex); - rcdev = NULL; - list_for_each_entry(r, &reset_controller_list, list) { - if (args.np == r->of_node) { - rcdev = r; - break; + /* + * There can be only one reset-gpio for regular devices, so + * don't bother with the "reset-gpios" phandle index. + */ + ret = of_parse_phandle_with_args(node, "reset-gpios", "#gpio-cells", + 0, &args); + if (ret) + return optional ? NULL : ERR_PTR(ret); + + gpio_fallback = true; + + ret = __reset_add_reset_gpio_device(&args); + if (ret) { + rstc = ERR_PTR(ret); + goto out_put; } } + mutex_lock(&reset_list_mutex); + rcdev = __reset_find_rcdev(&args, gpio_fallback); if (!rcdev) { rstc = ERR_PTR(-EPROBE_DEFER); - goto out; + goto out_unlock; } if (WARN_ON(args.args_count != rcdev->of_reset_n_cells)) { rstc = ERR_PTR(-EINVAL); - goto out; + goto out_unlock; } rstc_id = rcdev->of_xlate(rcdev, &args); if (rstc_id < 0) { rstc = ERR_PTR(rstc_id); - goto out; + goto out_unlock; } /* reset_list_mutex also protects the rcdev's reset_control list */ rstc = __reset_control_get_internal(rcdev, rstc_id, shared, acquired); -out: +out_unlock: mutex_unlock(&reset_list_mutex); +out_put: of_node_put(args.np); return rstc; diff --git a/include/linux/reset-controller.h b/include/linux/reset-controller.h index 0fa4f60e1186..357df16ede32 100644 --- a/include/linux/reset-controller.h +++ b/include/linux/reset-controller.h @@ -60,6 +60,9 @@ struct reset_control_lookup { * @reset_control_head: head of internal list of requested reset controls * @dev: corresponding driver model device struct * @of_node: corresponding device tree node as phandle target + * @of_args: for reset-gpios controllers: corresponding phandle args with + * of_node and GPIO number complementing of_node; either this or + * of_node should be present * @of_reset_n_cells: number of cells in reset line specifiers * @of_xlate: translation function to translate from specifier as found in the * device tree to id as given to the reset control ops, defaults @@ -73,6 +76,7 @@ struct reset_controller_dev { struct list_head reset_control_head; struct device *dev; struct device_node *of_node; + const struct of_phandle_args *of_args; int of_reset_n_cells; int (*of_xlate)(struct reset_controller_dev *rcdev, const struct of_phandle_args *reset_spec); -- cgit