// SPDX-License-Identifier: (GPL-2.0 OR MIT) // Copyright (c) 2018 BayLibre, SAS. // Author: Jerome Brunet <jbrunet@baylibre.com> #include <linux/clk.h> #include <linux/io.h> #include <linux/module.h> #include <linux/of_platform.h> #include <linux/reset-controller.h> #include <linux/spinlock.h> #include <dt-bindings/reset/amlogic,meson-axg-audio-arb.h> struct meson_audio_arb_data { struct reset_controller_dev rstc; void __iomem *regs; struct clk *clk; const unsigned int *reset_bits; spinlock_t lock; }; struct meson_audio_arb_match_data { const unsigned int *reset_bits; unsigned int reset_num; }; #define ARB_GENERAL_BIT 31 static const unsigned int axg_audio_arb_reset_bits[] = { [AXG_ARB_TODDR_A] = 0, [AXG_ARB_TODDR_B] = 1, [AXG_ARB_TODDR_C] = 2, [AXG_ARB_FRDDR_A] = 4, [AXG_ARB_FRDDR_B] = 5, [AXG_ARB_FRDDR_C] = 6, }; static const struct meson_audio_arb_match_data axg_audio_arb_match = { .reset_bits = axg_audio_arb_reset_bits, .reset_num = ARRAY_SIZE(axg_audio_arb_reset_bits), }; static const unsigned int sm1_audio_arb_reset_bits[] = { [AXG_ARB_TODDR_A] = 0, [AXG_ARB_TODDR_B] = 1, [AXG_ARB_TODDR_C] = 2, [AXG_ARB_FRDDR_A] = 4, [AXG_ARB_FRDDR_B] = 5, [AXG_ARB_FRDDR_C] = 6, [AXG_ARB_TODDR_D] = 3, [AXG_ARB_FRDDR_D] = 7, }; static const struct meson_audio_arb_match_data sm1_audio_arb_match = { .reset_bits = sm1_audio_arb_reset_bits, .reset_num = ARRAY_SIZE(sm1_audio_arb_reset_bits), }; static int meson_audio_arb_update(struct reset_controller_dev *rcdev, unsigned long id, bool assert) { u32 val; struct meson_audio_arb_data *arb = container_of(rcdev, struct meson_audio_arb_data, rstc); spin_lock(&arb->lock); val = readl(arb->regs); if (assert) val &= ~BIT(arb->reset_bits[id]); else val |= BIT(arb->reset_bits[id]); writel(val, arb->regs); spin_unlock(&arb->lock); return 0; } static int meson_audio_arb_status(struct reset_controller_dev *rcdev, unsigned long id) { u32 val; struct meson_audio_arb_data *arb = container_of(rcdev, struct meson_audio_arb_data, rstc); val = readl(arb->regs); return !(val & BIT(arb->reset_bits[id])); } static int meson_audio_arb_assert(struct reset_controller_dev *rcdev, unsigned long id) { return meson_audio_arb_update(rcdev, id, true); } static int meson_audio_arb_deassert(struct reset_controller_dev *rcdev, unsigned long id) { return meson_audio_arb_update(rcdev, id, false); } static const struct reset_control_ops meson_audio_arb_rstc_ops = { .assert = meson_audio_arb_assert, .deassert = meson_audio_arb_deassert, .status = meson_audio_arb_status, }; static const struct of_device_id meson_audio_arb_of_match[] = { { .compatible = "amlogic,meson-axg-audio-arb", .data = &axg_audio_arb_match, }, { .compatible = "amlogic,meson-sm1-audio-arb", .data = &sm1_audio_arb_match, }, {} }; MODULE_DEVICE_TABLE(of, meson_audio_arb_of_match); static int meson_audio_arb_remove(struct platform_device *pdev) { struct meson_audio_arb_data *arb = platform_get_drvdata(pdev); /* Disable all access */ spin_lock(&arb->lock); writel(0, arb->regs); spin_unlock(&arb->lock); clk_disable_unprepare(arb->clk); return 0; } static int meson_audio_arb_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; const struct meson_audio_arb_match_data *data; struct meson_audio_arb_data *arb; struct resource *res; int ret; data = of_device_get_match_data(dev); if (!data) return -EINVAL; arb = devm_kzalloc(dev, sizeof(*arb), GFP_KERNEL); if (!arb) return -ENOMEM; platform_set_drvdata(pdev, arb); arb->clk = devm_clk_get(dev, NULL); if (IS_ERR(arb->clk)) { if (PTR_ERR(arb->clk) != -EPROBE_DEFER) dev_err(dev, "failed to get clock\n"); return PTR_ERR(arb->clk); } res = platform_get_resource(pdev, IORESOURCE_MEM, 0); arb->regs = devm_ioremap_resource(dev, res); if (IS_ERR(arb->regs)) return PTR_ERR(arb->regs); spin_lock_init(&arb->lock); arb->reset_bits = data->reset_bits; arb->rstc.nr_resets = data->reset_num; arb->rstc.ops = &meson_audio_arb_rstc_ops; arb->rstc.of_node = dev->of_node; arb->rstc.owner = THIS_MODULE; /* * Enable general : * In the initial state, all memory interfaces are disabled * and the general bit is on */ ret = clk_prepare_enable(arb->clk); if (ret) { dev_err(dev, "failed to enable arb clock\n"); return ret; } writel(BIT(ARB_GENERAL_BIT), arb->regs); /* Register reset controller */ ret = devm_reset_controller_register(dev, &arb->rstc); if (ret) { dev_err(dev, "failed to register arb reset controller\n"); meson_audio_arb_remove(pdev); } return ret; } static struct platform_driver meson_audio_arb_pdrv = { .probe = meson_audio_arb_probe, .remove = meson_audio_arb_remove, .driver = { .name = "meson-audio-arb-reset", .of_match_table = meson_audio_arb_of_match, }, }; module_platform_driver(meson_audio_arb_pdrv); MODULE_DESCRIPTION("Amlogic A113 Audio Memory Arbiter"); MODULE_AUTHOR("Jerome Brunet <jbrunet@baylibre.com>"); MODULE_LICENSE("GPL v2");