Hi Andy, On Sun, May 28, 2017 at 12:41 AM, Andy Shevchenko <andy.shevchenko@xxxxxxxxx> wrote: > On Fri, May 26, 2017 at 6:32 AM, Joel Stanley <joel@xxxxxxxxx> wrote: >> This driver is a basic single-register reset controller driver that >> supports clearing a single bit in a register. >> > > While this makes sense, I'm wondering if there can be generic > interface for this from which we can derive this one and GPIO-based > one. Do we have a GPIO based one already? I couldn't find it. Having a think, it would be a very similar looking driver, but with little shared code. The context struct would contain a gpio pointer instead of regmap, probe would request a GPIO instead of a regmap and the assert/deassert/status callbacks would be gpiod_ calls. Given this is four of the four functions in this driver, do you think would be better off with two small drivers? Cheers, Joel > >> Signed-off-by: Joel Stanley <joel@xxxxxxxxx> >> --- >> drivers/reset/Kconfig | 6 +++ >> drivers/reset/Makefile | 1 + >> drivers/reset/reset-basic.c | 109 ++++++++++++++++++++++++++++++++++++++++++++ >> 3 files changed, 116 insertions(+) >> create mode 100644 drivers/reset/reset-basic.c >> >> diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig >> index d21c07ccc94e..980cda887dfe 100644 >> --- a/drivers/reset/Kconfig >> +++ b/drivers/reset/Kconfig >> @@ -28,6 +28,12 @@ config RESET_ATH79 >> This enables the ATH79 reset controller driver that supports the >> AR71xx SoC reset controller. >> >> +config RESET_BASIC >> + bool "Basic Reset Driver" >> + help >> + This enables a basic single-register reset controller driver that >> + supports clearing a single bit in a register. >> + >> config RESET_BERLIN >> bool "Berlin Reset Driver" if COMPILE_TEST >> default ARCH_BERLIN >> diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile >> index 02a74db94339..e8e8869e098d 100644 >> --- a/drivers/reset/Makefile >> +++ b/drivers/reset/Makefile >> @@ -4,6 +4,7 @@ obj-$(CONFIG_ARCH_STI) += sti/ >> obj-$(CONFIG_ARCH_TEGRA) += tegra/ >> obj-$(CONFIG_RESET_A10SR) += reset-a10sr.o >> obj-$(CONFIG_RESET_ATH79) += reset-ath79.o >> +obj-$(CONFIG_RESET_BASIC) += reset-basic.o >> obj-$(CONFIG_RESET_BERLIN) += reset-berlin.o >> obj-$(CONFIG_RESET_IMX7) += reset-imx7.o >> obj-$(CONFIG_RESET_LPC18XX) += reset-lpc18xx.o >> diff --git a/drivers/reset/reset-basic.c b/drivers/reset/reset-basic.c >> new file mode 100644 >> index 000000000000..62a676de9f62 >> --- /dev/null >> +++ b/drivers/reset/reset-basic.c >> @@ -0,0 +1,109 @@ >> +/* >> + * Copyright 2017 IBM Corperation >> + * >> + * Joel Stanley <joel@xxxxxxxxx> >> + * >> + * This program is free software; you can redistribute it and/or >> + * modify it under the terms of the GNU General Public License >> + * as published by the Free Software Foundation; either version >> + * 2 of the License, or (at your option) any later version. >> + */ >> + >> +#include <linux/delay.h> >> +#include <linux/init.h> >> +#include <linux/of.h> >> +#include <linux/of_address.h> >> +#include <linux/platform_device.h> >> +#include <linux/regmap.h> >> +#include <linux/mfd/syscon.h> >> +#include <linux/reset-controller.h> >> + >> +#define to_basic_reset_priv(p) \ >> + container_of((p), struct basic_reset_priv, rcdev) >> + >> +struct basic_reset_priv { >> + struct regmap *regmap; >> + struct reset_controller_dev rcdev; >> + u32 reg; >> +}; >> + >> +static int basic_reset_assert(struct reset_controller_dev *rcdev, >> + unsigned long id) >> +{ >> + struct basic_reset_priv *priv = to_basic_reset_priv(rcdev); >> + u32 mask = BIT(id); >> + >> + regmap_update_bits(priv->regmap, priv->reg, mask, mask); >> + >> + return 0; >> +} >> + >> +static int basic_reset_deassert(struct reset_controller_dev *rcdev, >> + unsigned long id) >> +{ >> + struct basic_reset_priv *priv = to_basic_reset_priv(rcdev); >> + u32 mask = BIT(id); >> + >> + regmap_update_bits(priv->regmap, priv->reg, mask, 0); >> + >> + return 0; >> +} >> + >> +static int basic_reset_status(struct reset_controller_dev *rcdev, >> + unsigned long id) >> +{ >> + struct basic_reset_priv *priv = to_basic_reset_priv(rcdev); >> + u32 mask = BIT(id); >> + u32 val; >> + >> + regmap_read(priv->regmap, priv->reg, &val); >> + >> + return !!(val & mask); >> +} >> + >> +static const struct reset_control_ops basic_reset_ops = { >> + .assert = basic_reset_assert, >> + .deassert = basic_reset_deassert, >> + .status = basic_reset_status, >> +}; >> + >> +static int basic_reset_probe(struct platform_device *pdev) >> +{ >> + struct device_node *parent_np = of_get_parent(pdev->dev.of_node); >> + struct basic_reset_priv *priv; >> + int ret; >> + >> + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); >> + if (!priv) >> + return -ENOMEM; >> + >> + priv->regmap = syscon_node_to_regmap(parent_np); >> + of_node_put(parent_np); >> + if (IS_ERR(priv->regmap)) >> + return PTR_ERR(priv->regmap); >> + >> + ret = of_property_read_u32(pdev->dev.of_node, "reg", &priv->reg); >> + if (ret) >> + return ret; >> + >> + priv->rcdev.owner = THIS_MODULE; >> + priv->rcdev.ops = &basic_reset_ops; >> + priv->rcdev.of_node = pdev->dev.of_node; >> + priv->rcdev.nr_resets = 32; >> + >> + return reset_controller_register(&priv->rcdev); >> +} >> + >> +static const struct of_device_id basic_reset_dt_match[] = { >> + { .compatible = "reset-basic" }, >> + { }, >> +}; >> + >> +static struct platform_driver basic_reset_driver = { >> + .probe = basic_reset_probe, >> + .driver = { >> + .name = "basic-reset", >> + .of_match_table = basic_reset_dt_match, >> + }, >> +}; >> +builtin_platform_driver(basic_reset_driver); >> -- >> 2.11.0 >> > > > > -- > With Best Regards, > Andy Shevchenko -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html