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
33 MODULE_LICENSE("GPL");
34
35 enum {
36 CD_GPIO = 0,
37 WP_GPIO,
38 NUM_GPIOS,
39 };
40
41 struct 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
to_of_mmc_spi(struct device * dev)48 static 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
of_mmc_spi_init(struct device * dev,irqreturn_t (* irqhandler)(int,void *),void * mmc)53 static 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
of_mmc_spi_exit(struct device * dev,void * mmc)62 static 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
mmc_spi_get_pdata(struct spi_device * spi)69 struct 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;
141 err_ocr:
142 kfree(oms);
143 return NULL;
144 }
145 EXPORT_SYMBOL(mmc_spi_get_pdata);
146
mmc_spi_put_pdata(struct spi_device * spi)147 void 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 }
159 EXPORT_SYMBOL(mmc_spi_put_pdata);
160