1/*
2 * OpenFirmware bindings for the MMC-over-SPI driver
3 *
4 * Copyright (c) MontaVista Software, Inc. 2008.
5 *
6 * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
7 *
8 * This program is free software; you can redistribute  it and/or modify it
9 * under  the terms of  the GNU General  Public License as published by the
10 * Free Software Foundation;  either version 2 of the  License, or (at your
11 * option) any later version.
12 */
13
14#include <linux/kernel.h>
15#include <linux/module.h>
16#include <linux/device.h>
17#include <linux/slab.h>
18#include <linux/irq.h>
19#include <linux/gpio.h>
20#include <linux/of.h>
21#include <linux/of_gpio.h>
22#include <linux/of_irq.h>
23#include <linux/spi/spi.h>
24#include <linux/spi/mmc_spi.h>
25#include <linux/mmc/core.h>
26#include <linux/mmc/host.h>
27
28/* For archs that don't support NO_IRQ (such as mips), provide a dummy value */
29#ifndef NO_IRQ
30#define NO_IRQ 0
31#endif
32
33MODULE_LICENSE("GPL");
34
35enum {
36	CD_GPIO = 0,
37	WP_GPIO,
38	NUM_GPIOS,
39};
40
41struct of_mmc_spi {
42	int gpios[NUM_GPIOS];
43	bool alow_gpios[NUM_GPIOS];
44	int detect_irq;
45	struct mmc_spi_platform_data pdata;
46};
47
48static struct of_mmc_spi *to_of_mmc_spi(struct device *dev)
49{
50	return container_of(dev->platform_data, struct of_mmc_spi, pdata);
51}
52
53static int of_mmc_spi_init(struct device *dev,
54			   irqreturn_t (*irqhandler)(int, void *), void *mmc)
55{
56	struct of_mmc_spi *oms = to_of_mmc_spi(dev);
57
58	return request_threaded_irq(oms->detect_irq, NULL, irqhandler, 0,
59				    dev_name(dev), mmc);
60}
61
62static void of_mmc_spi_exit(struct device *dev, void *mmc)
63{
64	struct of_mmc_spi *oms = to_of_mmc_spi(dev);
65
66	free_irq(oms->detect_irq, mmc);
67}
68
69struct mmc_spi_platform_data *mmc_spi_get_pdata(struct spi_device *spi)
70{
71	struct device *dev = &spi->dev;
72	struct device_node *np = dev->of_node;
73	struct of_mmc_spi *oms;
74	const u32 *voltage_ranges;
75	int num_ranges;
76	int i;
77	int ret = -EINVAL;
78
79	if (dev->platform_data || !np)
80		return dev->platform_data;
81
82	oms = kzalloc(sizeof(*oms), GFP_KERNEL);
83	if (!oms)
84		return NULL;
85
86	voltage_ranges = of_get_property(np, "voltage-ranges", &num_ranges);
87	num_ranges = num_ranges / sizeof(*voltage_ranges) / 2;
88	if (!voltage_ranges || !num_ranges) {
89		dev_err(dev, "OF: voltage-ranges unspecified\n");
90		goto err_ocr;
91	}
92
93	for (i = 0; i < num_ranges; i++) {
94		const int j = i * 2;
95		u32 mask;
96
97		mask = mmc_vddrange_to_ocrmask(be32_to_cpu(voltage_ranges[j]),
98					       be32_to_cpu(voltage_ranges[j + 1]));
99		if (!mask) {
100			ret = -EINVAL;
101			dev_err(dev, "OF: voltage-range #%d is invalid\n", i);
102			goto err_ocr;
103		}
104		oms->pdata.ocr_mask |= mask;
105	}
106
107	for (i = 0; i < ARRAY_SIZE(oms->gpios); i++) {
108		enum of_gpio_flags gpio_flags;
109
110		oms->gpios[i] = of_get_gpio_flags(np, i, &gpio_flags);
111		if (!gpio_is_valid(oms->gpios[i]))
112			continue;
113
114		if (gpio_flags & OF_GPIO_ACTIVE_LOW)
115			oms->alow_gpios[i] = true;
116	}
117
118	if (gpio_is_valid(oms->gpios[CD_GPIO])) {
119		oms->pdata.cd_gpio = oms->gpios[CD_GPIO];
120		oms->pdata.flags |= MMC_SPI_USE_CD_GPIO;
121		if (!oms->alow_gpios[CD_GPIO])
122			oms->pdata.caps2 |= MMC_CAP2_CD_ACTIVE_HIGH;
123	}
124	if (gpio_is_valid(oms->gpios[WP_GPIO])) {
125		oms->pdata.ro_gpio = oms->gpios[WP_GPIO];
126		oms->pdata.flags |= MMC_SPI_USE_RO_GPIO;
127		if (!oms->alow_gpios[WP_GPIO])
128			oms->pdata.caps2 |= MMC_CAP2_RO_ACTIVE_HIGH;
129	}
130
131	oms->detect_irq = irq_of_parse_and_map(np, 0);
132	if (oms->detect_irq != 0) {
133		oms->pdata.init = of_mmc_spi_init;
134		oms->pdata.exit = of_mmc_spi_exit;
135	} else {
136		oms->pdata.caps |= MMC_CAP_NEEDS_POLL;
137	}
138
139	dev->platform_data = &oms->pdata;
140	return dev->platform_data;
141err_ocr:
142	kfree(oms);
143	return NULL;
144}
145EXPORT_SYMBOL(mmc_spi_get_pdata);
146
147void mmc_spi_put_pdata(struct spi_device *spi)
148{
149	struct device *dev = &spi->dev;
150	struct device_node *np = dev->of_node;
151	struct of_mmc_spi *oms = to_of_mmc_spi(dev);
152
153	if (!dev->platform_data || !np)
154		return;
155
156	kfree(oms);
157	dev->platform_data = NULL;
158}
159EXPORT_SYMBOL(mmc_spi_put_pdata);
160