[linux-2.6-block.git] / drivers / irqchip / irq-ts4800.c

/*
 * Multiplexed-IRQs driver for TS-4800's FPGA
 *
 * Copyright (c) 2015 - Savoir-faire Linux
 *
 * This file is licensed under the terms of the GNU General Public
 * License version 2. This program is licensed "as is" without any
 * warranty of any kind, whether express or implied.
 */

#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/irqchip.h>
#include <linux/irqchip/chained_irq.h>
#include <linux/irqdomain.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/platform_device.h>

#define IRQ_MASK        0x4
#define IRQ_STATUS      0x8

struct ts4800_irq_data {
	void __iomem            *base;
	struct irq_domain       *domain;
	struct irq_chip         irq_chip;
};

static void ts4800_irq_mask(struct irq_data *d)
{
	struct ts4800_irq_data *data = irq_data_get_irq_chip_data(d);
	u16 reg = readw(data->base + IRQ_MASK);
	u16 mask = 1 << d->hwirq;

	writew(reg | mask, data->base + IRQ_MASK);
}

static void ts4800_irq_unmask(struct irq_data *d)
{
	struct ts4800_irq_data *data = irq_data_get_irq_chip_data(d);
	u16 reg = readw(data->base + IRQ_MASK);
	u16 mask = 1 << d->hwirq;

	writew(reg & ~mask, data->base + IRQ_MASK);
}

static int ts4800_irqdomain_map(struct irq_domain *d, unsigned int irq,
				irq_hw_number_t hwirq)
{
	struct ts4800_irq_data *data = d->host_data;

	irq_set_chip_and_handler(irq, &data->irq_chip, handle_simple_irq);
	irq_set_chip_data(irq, data);
	irq_set_noprobe(irq);

	return 0;
}

static const struct irq_domain_ops ts4800_ic_ops = {
	.map = ts4800_irqdomain_map,
	.xlate = irq_domain_xlate_onecell,
};

static void ts4800_ic_chained_handle_irq(struct irq_desc *desc)
{
	struct ts4800_irq_data *data = irq_desc_get_handler_data(desc);
	struct irq_chip *chip = irq_desc_get_chip(desc);
	u16 status = readw(data->base + IRQ_STATUS);

	chained_irq_enter(chip, desc);

	if (unlikely(status == 0)) {
		handle_bad_irq(desc);
		goto out;
	}

	do {
		unsigned int bit = __ffs(status);
		int irq = irq_find_mapping(data->domain, bit);

		status &= ~(1 << bit);
		generic_handle_irq(irq);
	} while (status);

out:
	chained_irq_exit(chip, desc);
}

static int ts4800_ic_probe(struct platform_device *pdev)
{
	struct device_node *node = pdev->dev.of_node;
	struct ts4800_irq_data *data;
	struct irq_chip *irq_chip;
	struct resource *res;
	int parent_irq;

	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	data->base = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(data->base))
		return PTR_ERR(data->base);

	writew(0xFFFF, data->base + IRQ_MASK);

	parent_irq = irq_of_parse_and_map(node, 0);
	if (!parent_irq) {
		dev_err(&pdev->dev, "failed to get parent IRQ\n");
		return -EINVAL;
	}

	irq_chip = &data->irq_chip;
	irq_chip->name = dev_name(&pdev->dev);
	irq_chip->irq_mask = ts4800_irq_mask;
	irq_chip->irq_unmask = ts4800_irq_unmask;

	data->domain = irq_domain_add_linear(node, 8, &ts4800_ic_ops, data);
	if (!data->domain) {
		dev_err(&pdev->dev, "cannot add IRQ domain\n");
		return -ENOMEM;
	}

	irq_set_chained_handler_and_data(parent_irq,
					 ts4800_ic_chained_handle_irq, data);

	platform_set_drvdata(pdev, data);

	return 0;
}

static int ts4800_ic_remove(struct platform_device *pdev)
{
	struct ts4800_irq_data *data = platform_get_drvdata(pdev);

	irq_domain_remove(data->domain);

	return 0;
}

static const struct of_device_id ts4800_ic_of_match[] = {
	{ .compatible = "technologic,ts4800-irqc", },
	{},
};
MODULE_DEVICE_TABLE(of, ts4800_ic_of_match);

static struct platform_driver ts4800_ic_driver = {
	.probe  = ts4800_ic_probe,
	.remove = ts4800_ic_remove,
	.driver = {
		.name = "ts4800-irqc",
		.of_match_table = ts4800_ic_of_match,
	},
};
module_platform_driver(ts4800_ic_driver);

MODULE_AUTHOR("Damien Riegel <damien.riegel@savoirfairelinux.com>");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:ts4800_irqc");
Commit	Line	Data
d01f8633 DR	1	/*
	2	* Multiplexed-IRQs driver for TS-4800's FPGA
	3	*
	4	* Copyright (c) 2015 - Savoir-faire Linux
	5	*
	6	* This file is licensed under the terms of the GNU General Public
	7	* License version 2. This program is licensed "as is" without any
	8	* warranty of any kind, whether express or implied.
	9	*/
	10
	11	#include <linux/interrupt.h>
	12	#include <linux/io.h>
	13	#include <linux/irq.h>
	14	#include <linux/irqchip.h>
	15	#include <linux/irqchip/chained_irq.h>
	16	#include <linux/irqdomain.h>
	17	#include <linux/module.h>
	18	#include <linux/of.h>
	19	#include <linux/of_address.h>
	20	#include <linux/of_irq.h>
	21	#include <linux/platform_device.h>
	22
	23	#define IRQ_MASK 0x4
	24	#define IRQ_STATUS 0x8
	25
	26	struct ts4800_irq_data {
	27	void __iomem *base;
	28	struct irq_domain *domain;
	29	struct irq_chip irq_chip;
	30	};
	31
	32	static void ts4800_irq_mask(struct irq_data *d)
	33	{
	34	struct ts4800_irq_data *data = irq_data_get_irq_chip_data(d);
	35	u16 reg = readw(data->base + IRQ_MASK);
	36	u16 mask = 1 << d->hwirq;
	37
	38	writew(reg \| mask, data->base + IRQ_MASK);
	39	}
	40
	41	static void ts4800_irq_unmask(struct irq_data *d)
	42	{
	43	struct ts4800_irq_data *data = irq_data_get_irq_chip_data(d);
	44	u16 reg = readw(data->base + IRQ_MASK);
	45	u16 mask = 1 << d->hwirq;
	46
	47	writew(reg & ~mask, data->base + IRQ_MASK);
	48	}
	49
	50	static int ts4800_irqdomain_map(struct irq_domain *d, unsigned int irq,
	51	irq_hw_number_t hwirq)
	52	{
	53	struct ts4800_irq_data *data = d->host_data;
	54
	55	irq_set_chip_and_handler(irq, &data->irq_chip, handle_simple_irq);
	56	irq_set_chip_data(irq, data);
	57	irq_set_noprobe(irq);
	58
	59	return 0;
	60	}
	61
e4e1c0ea	62	static const struct irq_domain_ops ts4800_ic_ops = {
d01f8633 DR	63	.map = ts4800_irqdomain_map,
	64	.xlate = irq_domain_xlate_onecell,
	65	};
	66
	67	static void ts4800_ic_chained_handle_irq(struct irq_desc *desc)
	68	{
	69	struct ts4800_irq_data *data = irq_desc_get_handler_data(desc);
	70	struct irq_chip *chip = irq_desc_get_chip(desc);
	71	u16 status = readw(data->base + IRQ_STATUS);
	72
	73	chained_irq_enter(chip, desc);
	74
	75	if (unlikely(status == 0)) {
	76	handle_bad_irq(desc);
	77	goto out;
	78	}
	79
	80	do {
	81	unsigned int bit = __ffs(status);
	82	int irq = irq_find_mapping(data->domain, bit);
	83
	84	status &= ~(1 << bit);
	85	generic_handle_irq(irq);
	86	} while (status);
	87
	88	out:
	89	chained_irq_exit(chip, desc);
	90	}
	91
	92	static int ts4800_ic_probe(struct platform_device *pdev)
	93	{
	94	struct device_node *node = pdev->dev.of_node;
	95	struct ts4800_irq_data *data;
	96	struct irq_chip *irq_chip;
	97	struct resource *res;
	98	int parent_irq;
	99
	100	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
	101	if (!data)
	102	return -ENOMEM;
	103
	104	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	105	data->base = devm_ioremap_resource(&pdev->dev, res);
	106	if (IS_ERR(data->base))
	107	return PTR_ERR(data->base);
	108
	109	writew(0xFFFF, data->base + IRQ_MASK);
	110
	111	parent_irq = irq_of_parse_and_map(node, 0);
	112	if (!parent_irq) {
	113	dev_err(&pdev->dev, "failed to get parent IRQ\n");
	114	return -EINVAL;
	115	}
	116
	117	irq_chip = &data->irq_chip;
	118	irq_chip->name = dev_name(&pdev->dev);
	119	irq_chip->irq_mask = ts4800_irq_mask;
	120	irq_chip->irq_unmask = ts4800_irq_unmask;
	121
	122	data->domain = irq_domain_add_linear(node, 8, &ts4800_ic_ops, data);
	123	if (!data->domain) {
	124	dev_err(&pdev->dev, "cannot add IRQ domain\n");
	125	return -ENOMEM;
	126	}
127
128	irq_set_chained_handler_and_data(parent_irq,
129	ts4800_ic_chained_handle_irq, data);
130
131	platform_set_drvdata(pdev, data);
132
133	return 0;
134	}
135
136	static int ts4800_ic_remove(struct platform_device *pdev)
137	{
138	struct ts4800_irq_data *data = platform_get_drvdata(pdev);
139
140	irq_domain_remove(data->domain);
141
142	return 0;
143	}
144
145	static const struct of_device_id ts4800_ic_of_match[] = {
146	{ .compatible = "technologic,ts4800-irqc", },
147	{},
148	};
149	MODULE_DEVICE_TABLE(of, ts4800_ic_of_match);
150
151	static struct platform_driver ts4800_ic_driver = {
152	.probe = ts4800_ic_probe,
153	.remove = ts4800_ic_remove,
154	.driver = {
155	.name = "ts4800-irqc",
156	.of_match_table = ts4800_ic_of_match,
157	},
158	};
159	module_platform_driver(ts4800_ic_driver);
160
161	MODULE_AUTHOR("Damien Riegel <damien.riegel@savoirfairelinux.com>");
162	MODULE_LICENSE("GPL v2");
163	MODULE_ALIAS("platform:ts4800_irqc");