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