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 struct resource *res_regs; 80 int irq, error, error2; 81 82 /* Get resources from platform device */ 83 irq = platform_get_irq(pdev, 0); 84 if (irq < 0) { 85 dev_err(&pdev->dev, "cannot find IRQ resource\n"); 86 return irq; 87 } 88 89 /* Private driver data */ 90 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); 91 if (!priv) 92 return -ENOMEM; 93 94 platform_set_drvdata(pdev, priv); 95 priv->dev = &pdev->dev; 96 spin_lock_init(&priv->lock); 97 98 /* Ioremap the registers */ 99 res_regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); 100 priv->reg_base = devm_ioremap_resource(&pdev->dev, res_regs); 101 if (IS_ERR(priv->reg_base)) 102 return PTR_ERR(priv->reg_base); 103 104 /* Get core clock */ 105 priv->clk = devm_clk_get(&pdev->dev, "core"); 106 if (IS_ERR(priv->clk)) 107 dev_warn(&pdev->dev, "cannot get core clock resource\n"); 108 109 /* Get sys clock */ 110 priv->sys_clk = devm_clk_get(&pdev->dev, "sys"); 111 if (IS_ERR(priv->sys_clk)) 112 dev_warn(&pdev->dev, "cannot get sys clock resource\n"); 113 /* 114 * Enabling the system clock before the register interface is 115 * accessed. ISR shouldn't get called with Sys Clock disabled, 116 * hence exiting probe with an error. 117 */ 118 if (!IS_ERR(priv->sys_clk)) { 119 error = clk_prepare_enable(priv->sys_clk); 120 if (error) { 121 dev_err(&pdev->dev, "cannot enable sys clock\n"); 122 return error; 123 } 124 } 125 126 /* Set up raw & hw decoder */ 127 error = img_ir_probe_raw(priv); 128 error2 = img_ir_probe_hw(priv); 129 if (error && error2) { 130 if (error == -ENODEV) 131 error = error2; 132 goto err_probe; 133 } 134 135 /* Get the IRQ */ 136 priv->irq = irq; 137 error = request_irq(priv->irq, img_ir_isr, 0, "img-ir", priv); 138 if (error) { 139 dev_err(&pdev->dev, "cannot register IRQ %u\n", 140 priv->irq); 141 error = -EIO; 142 goto err_irq; 143 } 144 145 img_ir_ident(priv); 146 img_ir_setup(priv); 147 148 return 0; 149 150 err_irq: 151 img_ir_remove_hw(priv); 152 img_ir_remove_raw(priv); 153 err_probe: 154 if (!IS_ERR(priv->sys_clk)) 155 clk_disable_unprepare(priv->sys_clk); 156 return error; 157 } 158 159 static int img_ir_remove(struct platform_device *pdev) 160 { 161 struct img_ir_priv *priv = platform_get_drvdata(pdev); 162 163 free_irq(priv->irq, priv); 164 img_ir_remove_hw(priv); 165 img_ir_remove_raw(priv); 166 167 if (!IS_ERR(priv->clk)) 168 clk_disable_unprepare(priv->clk); 169 if (!IS_ERR(priv->sys_clk)) 170 clk_disable_unprepare(priv->sys_clk); 171 return 0; 172 } 173 174 static SIMPLE_DEV_PM_OPS(img_ir_pmops, img_ir_suspend, img_ir_resume); 175 176 static const struct of_device_id img_ir_match[] = { 177 { .compatible = "img,ir-rev1" }, 178 {} 179 }; 180 MODULE_DEVICE_TABLE(of, img_ir_match); 181 182 static struct platform_driver img_ir_driver = { 183 .driver = { 184 .name = "img-ir", 185 .of_match_table = img_ir_match, 186 .pm = &img_ir_pmops, 187 }, 188 .probe = img_ir_probe, 189 .remove = img_ir_remove, 190 }; 191 192 module_platform_driver(img_ir_driver); 193 194 MODULE_AUTHOR("Imagination Technologies Ltd."); 195 MODULE_DESCRIPTION("ImgTec IR"); 196 MODULE_LICENSE("GPL"); 197