From: Alban Bedel Date: Mon, 3 Aug 2015 17:23:52 +0000 (+0200) Subject: reset: Add a driver for the reset controller on the AR71XX/AR9XXX X-Git-Tag: firefly_0821_release~176^2~1086^2~3^2~1^2~1 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=ff591a91225d3621a503bb18faa0f0d747a06e50;p=firefly-linux-kernel-4.4.55.git reset: Add a driver for the reset controller on the AR71XX/AR9XXX The AR71XX/AR9XXX SoC have a simple reset controller with one bit per reset line. Signed-off-by: Alban Bedel Acked-by: Ralf Baechle Signed-off-by: Philipp Zabel --- diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index aab7e46cadd5..3a3548f267b4 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -118,6 +118,7 @@ config ATH25 config ATH79 bool "Atheros AR71XX/AR724X/AR913X based boards" + select ARCH_HAS_RESET_CONTROLLER select ARCH_REQUIRE_GPIOLIB select BOOT_RAW select CEVT_R4K diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile index 157d421f755b..f8db9b744b3a 100644 --- a/drivers/reset/Makefile +++ b/drivers/reset/Makefile @@ -3,3 +3,4 @@ obj-$(CONFIG_ARCH_SOCFPGA) += reset-socfpga.o obj-$(CONFIG_ARCH_BERLIN) += reset-berlin.o obj-$(CONFIG_ARCH_SUNXI) += reset-sunxi.o obj-$(CONFIG_ARCH_STI) += sti/ +obj-$(CONFIG_ATH79) += reset-ath79.o diff --git a/drivers/reset/reset-ath79.c b/drivers/reset/reset-ath79.c new file mode 100644 index 000000000000..d2d290413113 --- /dev/null +++ b/drivers/reset/reset-ath79.c @@ -0,0 +1,128 @@ +/* + * Copyright (C) 2015 Alban Bedel + * + * 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. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include +#include +#include + +struct ath79_reset { + struct reset_controller_dev rcdev; + void __iomem *base; + spinlock_t lock; +}; + +static int ath79_reset_update(struct reset_controller_dev *rcdev, + unsigned long id, bool assert) +{ + struct ath79_reset *ath79_reset = + container_of(rcdev, struct ath79_reset, rcdev); + unsigned long flags; + u32 val; + + spin_lock_irqsave(&ath79_reset->lock, flags); + val = readl(ath79_reset->base); + if (assert) + val |= BIT(id); + else + val &= ~BIT(id); + writel(val, ath79_reset->base); + spin_unlock_irqrestore(&ath79_reset->lock, flags); + + return 0; +} + +static int ath79_reset_assert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + return ath79_reset_update(rcdev, id, true); +} + +static int ath79_reset_deassert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + return ath79_reset_update(rcdev, id, false); +} + +static int ath79_reset_status(struct reset_controller_dev *rcdev, + unsigned long id) +{ + struct ath79_reset *ath79_reset = + container_of(rcdev, struct ath79_reset, rcdev); + u32 val; + + val = readl(ath79_reset->base); + + return !!(val & BIT(id)); +} + +static struct reset_control_ops ath79_reset_ops = { + .assert = ath79_reset_assert, + .deassert = ath79_reset_deassert, + .status = ath79_reset_status, +}; + +static int ath79_reset_probe(struct platform_device *pdev) +{ + struct ath79_reset *ath79_reset; + struct resource *res; + + ath79_reset = devm_kzalloc(&pdev->dev, + sizeof(*ath79_reset), GFP_KERNEL); + if (!ath79_reset) + return -ENOMEM; + + platform_set_drvdata(pdev, ath79_reset); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + ath79_reset->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(ath79_reset->base)) + return PTR_ERR(ath79_reset->base); + + ath79_reset->rcdev.ops = &ath79_reset_ops; + ath79_reset->rcdev.owner = THIS_MODULE; + ath79_reset->rcdev.of_node = pdev->dev.of_node; + ath79_reset->rcdev.of_reset_n_cells = 1; + ath79_reset->rcdev.nr_resets = 32; + + return reset_controller_register(&ath79_reset->rcdev); +} + +static int ath79_reset_remove(struct platform_device *pdev) +{ + struct ath79_reset *ath79_reset = platform_get_drvdata(pdev); + + reset_controller_unregister(&ath79_reset->rcdev); + + return 0; +} + +static const struct of_device_id ath79_reset_dt_ids[] = { + { .compatible = "qca,ar7100-reset", }, + { }, +}; +MODULE_DEVICE_TABLE(of, ath79_reset_dt_ids); + +static struct platform_driver ath79_reset_driver = { + .probe = ath79_reset_probe, + .remove = ath79_reset_remove, + .driver = { + .name = "ath79-reset", + .of_match_table = ath79_reset_dt_ids, + }, +}; +module_platform_driver(ath79_reset_driver); + +MODULE_AUTHOR("Alban Bedel "); +MODULE_DESCRIPTION("AR71xx Reset Controller Driver"); +MODULE_LICENSE("GPL");