1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 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 interfaces 8 * (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 21 static 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 49 static 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 61 static 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 76 static 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 is 111 * 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; 145 146 err_irq: 147 img_ir_remove_hw(priv); 148 img_ir_remove_raw(priv); 149 err_probe: 150 if (!IS_ERR(priv->sys_clk)) 151 clk_disable_unprepare(priv->sys_clk); 152 return error; 153 } 154 155 static 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 } 168 169 static SIMPLE_DEV_PM_OPS(img_ir_pmops, img_ir_suspend, img_ir_resume); 170 171 static const struct of_device_id img_ir_match[] = { 172 { .compatible = "img,ir-rev1" }, 173 {} 174 }; 175 MODULE_DEVICE_TABLE(of, img_ir_match); 176 177 static 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 }; 186 187 module_platform_driver(img_ir_driver); 188 189 MODULE_AUTHOR("Imagination Technologies Ltd."); 190 MODULE_DESCRIPTION("ImgTec IR"); 191 MODULE_LICENSE("GPL"); 192