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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
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_read_gpio(struct device *dev, int gpio_num)
54{
55 struct of_mmc_spi *oms = to_of_mmc_spi(dev);
56 bool active_low = oms->alow_gpios[gpio_num];
57 bool value = gpio_get_value(oms->gpios[gpio_num]);
58
59 return active_low ^ value;
60}
61
62static int of_mmc_spi_get_cd(struct device *dev)
63{
64 return of_mmc_spi_read_gpio(dev, CD_GPIO);
65}
66
67static int of_mmc_spi_get_ro(struct device *dev)
68{
69 return of_mmc_spi_read_gpio(dev, WP_GPIO);
70}
71
72static int of_mmc_spi_init(struct device *dev,
73 irqreturn_t (*irqhandler)(int, void *), void *mmc)
74{
75 struct of_mmc_spi *oms = to_of_mmc_spi(dev);
76
77 return request_threaded_irq(oms->detect_irq, NULL, irqhandler, 0,
78 dev_name(dev), mmc);
79}
80
81static void of_mmc_spi_exit(struct device *dev, void *mmc)
82{
83 struct of_mmc_spi *oms = to_of_mmc_spi(dev);
84
85 free_irq(oms->detect_irq, mmc);
86}
87
88struct mmc_spi_platform_data *mmc_spi_get_pdata(struct spi_device *spi)
89{
90 struct device *dev = &spi->dev;
91 struct device_node *np = dev->of_node;
92 struct of_mmc_spi *oms;
93 const u32 *voltage_ranges;
94 int num_ranges;
95 int i;
96 int ret = -EINVAL;
97
98 if (dev->platform_data || !np)
99 return dev->platform_data;
100
101 oms = kzalloc(sizeof(*oms), GFP_KERNEL);
102 if (!oms)
103 return NULL;
104
105 voltage_ranges = of_get_property(np, "voltage-ranges", &num_ranges);
106 num_ranges = num_ranges / sizeof(*voltage_ranges) / 2;
107 if (!voltage_ranges || !num_ranges) {
108 dev_err(dev, "OF: voltage-ranges unspecified\n");
109 goto err_ocr;
110 }
111
112 for (i = 0; i < num_ranges; i++) {
113 const int j = i * 2;
114 u32 mask;
115
116 mask = mmc_vddrange_to_ocrmask(be32_to_cpu(voltage_ranges[j]),
117 be32_to_cpu(voltage_ranges[j + 1]));
118 if (!mask) {
119 ret = -EINVAL;
120 dev_err(dev, "OF: voltage-range #%d is invalid\n", i);
121 goto err_ocr;
122 }
123 oms->pdata.ocr_mask |= mask;
124 }
125
126 for (i = 0; i < ARRAY_SIZE(oms->gpios); i++) {
127 enum of_gpio_flags gpio_flags;
128
129 oms->gpios[i] = of_get_gpio_flags(np, i, &gpio_flags);
130 if (!gpio_is_valid(oms->gpios[i]))
131 continue;
132
133 ret = gpio_request(oms->gpios[i], dev_name(dev));
134 if (ret < 0) {
135 oms->gpios[i] = -EINVAL;
136 continue;
137 }
138
139 if (gpio_flags & OF_GPIO_ACTIVE_LOW)
140 oms->alow_gpios[i] = true;
141 }
142
143 if (gpio_is_valid(oms->gpios[CD_GPIO]))
144 oms->pdata.get_cd = of_mmc_spi_get_cd;
145 if (gpio_is_valid(oms->gpios[WP_GPIO]))
146 oms->pdata.get_ro = of_mmc_spi_get_ro;
147
148 oms->detect_irq = irq_of_parse_and_map(np, 0);
149 if (oms->detect_irq != NO_IRQ) {
150 oms->pdata.init = of_mmc_spi_init;
151 oms->pdata.exit = of_mmc_spi_exit;
152 } else {
153 oms->pdata.caps |= MMC_CAP_NEEDS_POLL;
154 }
155
156 dev->platform_data = &oms->pdata;
157 return dev->platform_data;
158err_ocr:
159 kfree(oms);
160 return NULL;
161}
162EXPORT_SYMBOL(mmc_spi_get_pdata);
163
164void mmc_spi_put_pdata(struct spi_device *spi)
165{
166 struct device *dev = &spi->dev;
167 struct device_node *np = dev->of_node;
168 struct of_mmc_spi *oms = to_of_mmc_spi(dev);
169 int i;
170
171 if (!dev->platform_data || !np)
172 return;
173
174 for (i = 0; i < ARRAY_SIZE(oms->gpios); i++) {
175 if (gpio_is_valid(oms->gpios[i]))
176 gpio_free(oms->gpios[i]);
177 }
178 kfree(oms);
179 dev->platform_data = NULL;
180}
181EXPORT_SYMBOL(mmc_spi_put_pdata);
182
