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(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, data: 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(raw: &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(hw: &priv->hw)) |
43 | img_ir_isr_hw(priv, irq_status); |
44 | |
45 | spin_unlock(lock: &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, data: 0); |
53 | |
54 | img_ir_setup_raw(priv); |
55 | img_ir_setup_hw(priv); |
56 | |
57 | if (!IS_ERR(ptr: priv->clk)) |
58 | clk_prepare_enable(clk: 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(dev: &pdev->dev, size: sizeof(*priv), GFP_KERNEL); |
88 | if (!priv) |
89 | return -ENOMEM; |
90 | |
91 | platform_set_drvdata(pdev, data: 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, index: 0); |
97 | if (IS_ERR(ptr: priv->reg_base)) |
98 | return PTR_ERR(ptr: priv->reg_base); |
99 | |
100 | /* Get core clock */ |
101 | priv->clk = devm_clk_get(dev: &pdev->dev, id: "core" ); |
102 | if (IS_ERR(ptr: 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(dev: &pdev->dev, id: "sys" ); |
107 | if (IS_ERR(ptr: 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(ptr: priv->sys_clk)) { |
115 | error = clk_prepare_enable(clk: 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(irq: priv->irq, handler: img_ir_isr, flags: 0, name: "img-ir" , dev: 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(ptr: priv->sys_clk)) |
151 | clk_disable_unprepare(clk: 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(ptr: priv->clk)) |
164 | clk_disable_unprepare(clk: priv->clk); |
165 | if (!IS_ERR(ptr: priv->sys_clk)) |
166 | clk_disable_unprepare(clk: 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 | |