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brintos / linux-shallow public Read only

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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * ImgTec IR Decoder found in PowerDown Controller.4 *5 * Copyright 2010-2014 Imagination Technologies Ltd.6 *7 * This contains core img-ir code for setting up the driver. The two interfaces8 * (raw and hardware decode) are handled separately.9 */10 11#include <linux/clk.h>12#include <linux/init.h>13#include <linux/interrupt.h>14#include <linux/io.h>15#include <linux/module.h>16#include <linux/platform_device.h>17#include <linux/slab.h>18#include <linux/spinlock.h>19#include "img-ir.h"20 21static irqreturn_t img_ir_isr(int irq, void *dev_id)22{23	struct img_ir_priv *priv = dev_id;24	u32 irq_status;25 26	spin_lock(&priv->lock);27	/* we have to clear irqs before reading */28	irq_status = img_ir_read(priv, IMG_IR_IRQ_STATUS);29	img_ir_write(priv, IMG_IR_IRQ_CLEAR, irq_status);30 31	/* don't handle valid data irqs if we're only interested in matches */32	irq_status &= img_ir_read(priv, IMG_IR_IRQ_ENABLE);33 34	/* hand off edge interrupts to raw decode handler */35	if (irq_status & IMG_IR_IRQ_EDGE && img_ir_raw_enabled(&priv->raw))36		img_ir_isr_raw(priv, irq_status);37 38	/* hand off hardware match interrupts to hardware decode handler */39	if (irq_status & (IMG_IR_IRQ_DATA_MATCH |40			  IMG_IR_IRQ_DATA_VALID |41			  IMG_IR_IRQ_DATA2_VALID) &&42	    img_ir_hw_enabled(&priv->hw))43		img_ir_isr_hw(priv, irq_status);44 45	spin_unlock(&priv->lock);46	return IRQ_HANDLED;47}48 49static void img_ir_setup(struct img_ir_priv *priv)50{51	/* start off with interrupts disabled */52	img_ir_write(priv, IMG_IR_IRQ_ENABLE, 0);53 54	img_ir_setup_raw(priv);55	img_ir_setup_hw(priv);56 57	if (!IS_ERR(priv->clk))58		clk_prepare_enable(priv->clk);59}60 61static void img_ir_ident(struct img_ir_priv *priv)62{63	u32 core_rev = img_ir_read(priv, IMG_IR_CORE_REV);64 65	dev_info(priv->dev,66		 "IMG IR Decoder (%d.%d.%d.%d) probed successfully\n",67		 (core_rev & IMG_IR_DESIGNER) >> IMG_IR_DESIGNER_SHIFT,68		 (core_rev & IMG_IR_MAJOR_REV) >> IMG_IR_MAJOR_REV_SHIFT,69		 (core_rev & IMG_IR_MINOR_REV) >> IMG_IR_MINOR_REV_SHIFT,70		 (core_rev & IMG_IR_MAINT_REV) >> IMG_IR_MAINT_REV_SHIFT);71	dev_info(priv->dev, "Modes:%s%s\n",72		 img_ir_hw_enabled(&priv->hw) ? " hardware" : "",73		 img_ir_raw_enabled(&priv->raw) ? " raw" : "");74}75 76static int img_ir_probe(struct platform_device *pdev)77{78	struct img_ir_priv *priv;79	int irq, error, error2;80 81	/* Get resources from platform device */82	irq = platform_get_irq(pdev, 0);83	if (irq < 0)84		return irq;85 86	/* Private driver data */87	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);88	if (!priv)89		return -ENOMEM;90 91	platform_set_drvdata(pdev, priv);92	priv->dev = &pdev->dev;93	spin_lock_init(&priv->lock);94 95	/* Ioremap the registers */96	priv->reg_base = devm_platform_ioremap_resource(pdev, 0);97	if (IS_ERR(priv->reg_base))98		return PTR_ERR(priv->reg_base);99 100	/* Get core clock */101	priv->clk = devm_clk_get(&pdev->dev, "core");102	if (IS_ERR(priv->clk))103		dev_warn(&pdev->dev, "cannot get core clock resource\n");104 105	/* Get sys clock */106	priv->sys_clk = devm_clk_get(&pdev->dev, "sys");107	if (IS_ERR(priv->sys_clk))108		dev_warn(&pdev->dev, "cannot get sys clock resource\n");109	/*110	 * Enabling the system clock before the register interface is111	 * accessed. ISR shouldn't get called with Sys Clock disabled,112	 * hence exiting probe with an error.113	 */114	if (!IS_ERR(priv->sys_clk)) {115		error = clk_prepare_enable(priv->sys_clk);116		if (error) {117			dev_err(&pdev->dev, "cannot enable sys clock\n");118			return error;119		}120	}121 122	/* Set up raw & hw decoder */123	error = img_ir_probe_raw(priv);124	error2 = img_ir_probe_hw(priv);125	if (error && error2) {126		if (error == -ENODEV)127			error = error2;128		goto err_probe;129	}130 131	/* Get the IRQ */132	priv->irq = irq;133	error = request_irq(priv->irq, img_ir_isr, 0, "img-ir", priv);134	if (error) {135		dev_err(&pdev->dev, "cannot register IRQ %u\n",136			priv->irq);137		error = -EIO;138		goto err_irq;139	}140 141	img_ir_ident(priv);142	img_ir_setup(priv);143 144	return 0;145 146err_irq:147	img_ir_remove_hw(priv);148	img_ir_remove_raw(priv);149err_probe:150	if (!IS_ERR(priv->sys_clk))151		clk_disable_unprepare(priv->sys_clk);152	return error;153}154 155static void img_ir_remove(struct platform_device *pdev)156{157	struct img_ir_priv *priv = platform_get_drvdata(pdev);158 159	free_irq(priv->irq, priv);160	img_ir_remove_hw(priv);161	img_ir_remove_raw(priv);162 163	if (!IS_ERR(priv->clk))164		clk_disable_unprepare(priv->clk);165	if (!IS_ERR(priv->sys_clk))166		clk_disable_unprepare(priv->sys_clk);167}168 169static SIMPLE_DEV_PM_OPS(img_ir_pmops, img_ir_suspend, img_ir_resume);170 171static const struct of_device_id img_ir_match[] = {172	{ .compatible = "img,ir-rev1" },173	{}174};175MODULE_DEVICE_TABLE(of, img_ir_match);176 177static struct platform_driver img_ir_driver = {178	.driver = {179		.name = "img-ir",180		.of_match_table	= img_ir_match,181		.pm = &img_ir_pmops,182	},183	.probe = img_ir_probe,184	.remove_new = img_ir_remove,185};186 187module_platform_driver(img_ir_driver);188 189MODULE_AUTHOR("Imagination Technologies Ltd.");190MODULE_DESCRIPTION("ImgTec IR");191MODULE_LICENSE("GPL");192