Robert Jarzmik | aa8d6b7 | 2015-04-24 22:22:19 +0200 | [diff] [blame] | 1 | /* |
| 2 | * Intel Reference Systems cplds |
| 3 | * |
| 4 | * Copyright (C) 2014 Robert Jarzmik |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License as published by |
| 8 | * the Free Software Foundation; either version 2 of the License, or |
| 9 | * (at your option) any later version. |
| 10 | * |
| 11 | * Cplds motherboard driver, supporting lubbock and mainstone SoC board. |
| 12 | */ |
| 13 | |
| 14 | #include <linux/bitops.h> |
| 15 | #include <linux/gpio.h> |
| 16 | #include <linux/gpio/consumer.h> |
| 17 | #include <linux/interrupt.h> |
| 18 | #include <linux/io.h> |
| 19 | #include <linux/irq.h> |
| 20 | #include <linux/irqdomain.h> |
| 21 | #include <linux/mfd/core.h> |
| 22 | #include <linux/module.h> |
| 23 | #include <linux/of_platform.h> |
| 24 | |
| 25 | #define FPGA_IRQ_MASK_EN 0x0 |
| 26 | #define FPGA_IRQ_SET_CLR 0x10 |
| 27 | |
| 28 | #define CPLDS_NB_IRQ 32 |
| 29 | |
| 30 | struct cplds { |
| 31 | void __iomem *base; |
| 32 | int irq; |
| 33 | unsigned int irq_mask; |
| 34 | struct gpio_desc *gpio0; |
| 35 | struct irq_domain *irqdomain; |
| 36 | }; |
| 37 | |
| 38 | static irqreturn_t cplds_irq_handler(int in_irq, void *d) |
| 39 | { |
| 40 | struct cplds *fpga = d; |
| 41 | unsigned long pending; |
| 42 | unsigned int bit; |
| 43 | |
| 44 | pending = readl(fpga->base + FPGA_IRQ_SET_CLR) & fpga->irq_mask; |
| 45 | for_each_set_bit(bit, &pending, CPLDS_NB_IRQ) |
| 46 | generic_handle_irq(irq_find_mapping(fpga->irqdomain, bit)); |
| 47 | |
| 48 | return IRQ_HANDLED; |
| 49 | } |
| 50 | |
| 51 | static void cplds_irq_mask_ack(struct irq_data *d) |
| 52 | { |
| 53 | struct cplds *fpga = irq_data_get_irq_chip_data(d); |
| 54 | unsigned int cplds_irq = irqd_to_hwirq(d); |
| 55 | unsigned int set, bit = BIT(cplds_irq); |
| 56 | |
| 57 | fpga->irq_mask &= ~bit; |
| 58 | writel(fpga->irq_mask, fpga->base + FPGA_IRQ_MASK_EN); |
| 59 | set = readl(fpga->base + FPGA_IRQ_SET_CLR); |
| 60 | writel(set & ~bit, fpga->base + FPGA_IRQ_SET_CLR); |
| 61 | } |
| 62 | |
| 63 | static void cplds_irq_unmask(struct irq_data *d) |
| 64 | { |
| 65 | struct cplds *fpga = irq_data_get_irq_chip_data(d); |
| 66 | unsigned int cplds_irq = irqd_to_hwirq(d); |
| 67 | unsigned int bit = BIT(cplds_irq); |
| 68 | |
| 69 | fpga->irq_mask |= bit; |
| 70 | writel(fpga->irq_mask, fpga->base + FPGA_IRQ_MASK_EN); |
| 71 | } |
| 72 | |
| 73 | static struct irq_chip cplds_irq_chip = { |
| 74 | .name = "pxa_cplds", |
| 75 | .irq_mask_ack = cplds_irq_mask_ack, |
| 76 | .irq_unmask = cplds_irq_unmask, |
| 77 | .flags = IRQCHIP_MASK_ON_SUSPEND | IRQCHIP_SKIP_SET_WAKE, |
| 78 | }; |
| 79 | |
| 80 | static int cplds_irq_domain_map(struct irq_domain *d, unsigned int irq, |
| 81 | irq_hw_number_t hwirq) |
| 82 | { |
| 83 | struct cplds *fpga = d->host_data; |
| 84 | |
| 85 | irq_set_chip_and_handler(irq, &cplds_irq_chip, handle_level_irq); |
| 86 | irq_set_chip_data(irq, fpga); |
| 87 | |
| 88 | return 0; |
| 89 | } |
| 90 | |
| 91 | static const struct irq_domain_ops cplds_irq_domain_ops = { |
| 92 | .xlate = irq_domain_xlate_twocell, |
| 93 | .map = cplds_irq_domain_map, |
| 94 | }; |
| 95 | |
| 96 | static int cplds_resume(struct platform_device *pdev) |
| 97 | { |
| 98 | struct cplds *fpga = platform_get_drvdata(pdev); |
| 99 | |
| 100 | writel(fpga->irq_mask, fpga->base + FPGA_IRQ_MASK_EN); |
| 101 | |
| 102 | return 0; |
| 103 | } |
| 104 | |
| 105 | static int cplds_probe(struct platform_device *pdev) |
| 106 | { |
| 107 | struct resource *res; |
| 108 | struct cplds *fpga; |
| 109 | int ret; |
| 110 | unsigned int base_irq = 0; |
| 111 | unsigned long irqflags = 0; |
| 112 | |
| 113 | fpga = devm_kzalloc(&pdev->dev, sizeof(*fpga), GFP_KERNEL); |
| 114 | if (!fpga) |
| 115 | return -ENOMEM; |
| 116 | |
| 117 | res = platform_get_resource(pdev, IORESOURCE_IRQ, 0); |
| 118 | if (res) { |
| 119 | fpga->irq = (unsigned int)res->start; |
| 120 | irqflags = res->flags; |
| 121 | } |
| 122 | if (!fpga->irq) |
| 123 | return -ENODEV; |
| 124 | |
| 125 | base_irq = platform_get_irq(pdev, 1); |
| 126 | if (base_irq < 0) |
| 127 | base_irq = 0; |
| 128 | |
| 129 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| 130 | fpga->base = devm_ioremap_resource(&pdev->dev, res); |
| 131 | if (IS_ERR(fpga->base)) |
| 132 | return PTR_ERR(fpga->base); |
| 133 | |
| 134 | platform_set_drvdata(pdev, fpga); |
| 135 | |
| 136 | writel(fpga->irq_mask, fpga->base + FPGA_IRQ_MASK_EN); |
| 137 | writel(0, fpga->base + FPGA_IRQ_SET_CLR); |
| 138 | |
| 139 | ret = devm_request_irq(&pdev->dev, fpga->irq, cplds_irq_handler, |
| 140 | irqflags, dev_name(&pdev->dev), fpga); |
| 141 | if (ret == -ENOSYS) |
| 142 | return -EPROBE_DEFER; |
| 143 | |
| 144 | if (ret) { |
| 145 | dev_err(&pdev->dev, "couldn't request main irq%d: %d\n", |
| 146 | fpga->irq, ret); |
| 147 | return ret; |
| 148 | } |
| 149 | |
| 150 | irq_set_irq_wake(fpga->irq, 1); |
| 151 | fpga->irqdomain = irq_domain_add_linear(pdev->dev.of_node, |
| 152 | CPLDS_NB_IRQ, |
| 153 | &cplds_irq_domain_ops, fpga); |
| 154 | if (!fpga->irqdomain) |
| 155 | return -ENODEV; |
| 156 | |
| 157 | if (base_irq) { |
| 158 | ret = irq_create_strict_mappings(fpga->irqdomain, base_irq, 0, |
| 159 | CPLDS_NB_IRQ); |
| 160 | if (ret) { |
| 161 | dev_err(&pdev->dev, "couldn't create the irq mapping %d..%d\n", |
| 162 | base_irq, base_irq + CPLDS_NB_IRQ); |
| 163 | return ret; |
| 164 | } |
| 165 | } |
| 166 | |
| 167 | return 0; |
| 168 | } |
| 169 | |
| 170 | static int cplds_remove(struct platform_device *pdev) |
| 171 | { |
| 172 | struct cplds *fpga = platform_get_drvdata(pdev); |
| 173 | |
| 174 | irq_set_chip_and_handler(fpga->irq, NULL, NULL); |
| 175 | |
| 176 | return 0; |
| 177 | } |
| 178 | |
| 179 | static const struct of_device_id cplds_id_table[] = { |
| 180 | { .compatible = "intel,lubbock-cplds-irqs", }, |
| 181 | { .compatible = "intel,mainstone-cplds-irqs", }, |
| 182 | { } |
| 183 | }; |
| 184 | MODULE_DEVICE_TABLE(of, cplds_id_table); |
| 185 | |
| 186 | static struct platform_driver cplds_driver = { |
| 187 | .driver = { |
| 188 | .name = "pxa_cplds_irqs", |
| 189 | .of_match_table = of_match_ptr(cplds_id_table), |
| 190 | }, |
| 191 | .probe = cplds_probe, |
| 192 | .remove = cplds_remove, |
| 193 | .resume = cplds_resume, |
| 194 | }; |
| 195 | |
| 196 | module_platform_driver(cplds_driver); |
| 197 | |
| 198 | MODULE_DESCRIPTION("PXA Cplds interrupts driver"); |
| 199 | MODULE_AUTHOR("Robert Jarzmik <robert.jarzmik@free.fr>"); |
| 200 | MODULE_LICENSE("GPL"); |